Ijsrtm vol 1 (2) april 2013 [issn 2321 2543] giap india

International Journal of Students Research in Technology & Management Vol 1(2), April 2013, pg 82-88

www.giapjournals.com Page 82

STRUCTURE AND TEXTURE SYNTHESIS Pragnesh Patel, Shailesh Gupta, Haider Zafar, Nilesh Deotale

Computer Department, Mumbai University Lokmanya Tilak college of Engineering, Koparkhairne, Navi Mumbai.

[email protected], [email protected], [email protected]

Abstract

An approach for filling-in blocks of missing data in wireless image transmission is presented in this

paper. When compression algorithms such as JPEG are used as part of the wireless transmission

process, images are first tiled into blocks of 8x8 pixels. When such images are transmitted over

fading channels, the effects of noise can destroy entire blocks of the image. Instead of using

common retransmission query protocols, we aim to reconstruct the lost data using correlation

between the lost block and its neighbours. If the lost block contained structure, it is reconstructed

using an image inpainting algorithm, while texture synthesis is used for the textured blocks. The

switch between the two schemes is done in a fully automatic fashion based on the surrounding

available blocks. The performance of this method is tested for various images and combinations of

lost blocks.

Keywords - Restoration, interpolation, inpainting, filling-in, texture synthesis, JPEG, wireless

transmission ,compression.

I. INTRODUCTION

General purpose images are most commonly compressed by lossy JPEG. JPEG divides the image into

blocks of 8x8 pixels and calculates a two-dimensional (2-D) discrete cosine transform (DCT),

followed by quantization and Huffman encoding; see [1]. In common wireless scenarios, the image is

transmitted over the wireless channel block by block. Due to severe fading, we may lose an entire

block, even several consecutive blocks of an image. In [2] the report that average packet loss rate in a

wireless environment is 3.6% and occurs in a bursty fashion. In the worst case, a whole line of image

blocks might be lost. Note that JPEG uses differential encoding for storing the average (dc) value of

successive pixels. Hence, even if a single block is lost, the remaining blocks in that line (or reset

interval) might be received without their correct average (dc) value. Two common techniques to make

the transmission robust are forward error correction (FEC) and automatic retransmission query

protocols (ARQ). Of these, FEC needs extra error correction packets to be transmitted. As noted in [3],

ARQ lowers data transmission rates and can further increase the network congestion which initially

induced the packet loss. Instead, we show that it is

Possible to satisfactorily reconstruct the lost blocks by using the available information surrounding

them this will result in an increase in bandwidth efficiency of the transmission. The basic idea is to

first automatically classify the block as textured or structured (containing edges), and then fill-in the

missing block with information propagated from the surrounding pixels. In the case of structured



blocks, the inpainting algorithm in [4] is used; while for textured regions we follow [5].2 We test the

proposed scheme with a variety of images and simulated block losses. We also combine this approach

with JPEG compression itself, where the encoder voluntarily skips blocks, and these are reconstructed

at the decoder in the same fashion as in the wireless scenario. This process improves the compression

ratio, at little or no quality degradation.

II. PROPOSED ALGORITHM

A. Image Transform Coding For JPEG Compression Algorithm.

The Joint Photographic Expert Group (JPEG), Formed as a joint ISO and CCITT working committee,

is focused exclusively on still image compression.JPEG is compression standard for still color image

and gray-scale image, otherwise known as continuous-tone images. The JPEG compression scheme is

lossy and utilizes forward discrete cosine transform, a uniform quantizer and entropy encoding. The

DCT function removes data redundancy by transforming data from a spatial domain to a frequency

domain: the quantizer quantizes DCT coefficients with weighting functions to generate quantized

DCT coefficients optimized for human eye; and the entropy encoder minimizes the entropy of the

quantized DCT coefficents. By this methodology, the reduction of a large volume of data to a smaller

version is achived, discarding information that has little visual effect, and further compression of the

data by takingadvantage of its spatial characteristics.

B. The Discrete Cosine Transform(DCT)

DCT is a mathematical operation closely related to Fourier Transform. In the Spatial domain the

image requires lots if data points. Once image is converted to frequency domain using Fourier

transform family, only a few points are required to present the same image, because image contains

only a few frequency components.

This technique can be applied to a color image. A color image is composed of pixels. These pixels

have RGB color values, each with its x and y coordinates using 8X8 or 16X16matrix for each primary

color. When considered over an 8X8 matrix of 64 values, each with x and y coordinates, we have a

three dimensional representation of pixel called a spatial representation or spatial domain.

Compression algorithm, the input image is subdivided into 8-by-8 or 16-by-16 non-overlapping

blocks, and the two-dimensional DCT is calculated for each block. The DCT coefficients are then

quantized, coded, and transmitted. The JPEG receiver decodes the quantized DCT coefficients,

calculates the inverse two-dimensional DCT of each block, and then puts the blocks back unruffled

into a single image. For typical images, many of the DCT coefficients have values near to zero; these

coefficients can be cast-off without seriously disturbing the quality of the reconstructed image. A two

dimensional DCT of an M by N matrix A is defined as given in eqn(2):



cos2 1

2

2 12

,

0 1

0 1 …. (2)

Where, 1

√, 0

2, 1 1

1√

, 0

2, 1 1

The DCT is invertible transformation and its inverse is given as:

cos2 1

2

2 12

,

0 1

0 1

Where, 1

√, 0

2, 1 1

1√

, 0

2, 1 1

The DCT based encoder can be thought of as basically compression of a stream of 8 X 8 blocks of

image sections. Each 8 X 8 block makes its way through each processing step, and produces Output in

compressed form into the data stream. Because nearby image pixels are highly associated, the

‘forward’ DCT (FDCT) processing step lays the foundation for accomplishing data compression by

concentrating most of the signal in the lower spatial frequencies. For atypical 8 X 8 sample block

from a classic source image, most of the spatial frequencies have zero or near-zero amplitude and



need not be encoded. In principle, the DCT presents no loss to the source image samples; it purely

transforms them to a realm in which they can be more competently encoded.

After output from the FDCT, each of the 64 DCT coefficients are uniformly quantized in aggregation

with a carefully designed 64 – element Quantization Table. At the decoder, the quantized values are

multiplied by the respective QT elements to recover the original values.

After quantization, all of the quantized coefficients are well-arranged into the “zig-zag” sequence.

This arrangement helps to facilitate entropy encoding by assigning low-frequency non-zero

coefficients before high-frequency coefficients. The DC coefficient, which contains a significant

fraction of the complete image energy, is differentially encoded.

The reconstructions of lost blocks are in three steps:-

1. Classify lost blocks into two types i.e. texture and structure

2. Synthesize blocks which were classified as texture ;

3. To fill in blocks which were classified as structure

C. Block Classification:-

The first step in image reconstruction is to classify the errors i.e. whether they are texture or structure.

This process is done after receiving the image on receiver side. After receiving the image receiver

checks the pixels surrounding the lost block. For doing this we will use the method given by[11] . To

determine whether the image contains texture or not we just define some threshold value to the local

surrounding pixels. For assigning threshold values to the pixels we use method given by as follows

2

Where UB and LB are upper and lower threshold value s. The threshold value vary between 0 and

1.We have used UB=0.16 and LB=0.04. as suggested in .

The above method is applied for each 8x8 block in the immediate neighborhood of the lost

block. If the block contains even a single structure then we have to consider the structure first, also

there is some limitation in algorithm stated in [11]

To overcome this limitation we will divide the image in 8 neighbor of 8x8 block and calculate the

difference of them if 4 continuous difference is less than threshold value we will assign that pixel as

structure.

D. Texture synthesis procedure

Most schemes reported in the literature deal with image transmission in error-prone environments

using a combination of source and channel coding. we describe a packetization scheme in which the

DCT coefficients array generated by JPEG is grouped such that bursty (consecutive) packet loss

during transmission is scattered into a pseudo-random loss in the image domain (i.e., consecutive

blocks are rarely lost in the image domain). The ensuing reconstruction scheme benefits because,



most frequency components can be recovered from adjacent blocks. However, large bursts may cause

the errors to cluster in the image, and reconstruction suffers. It should be noted that the packetization

scheme proposed in , when used with the reconstruction scheme described in our paper, is expected to

further improve on the results reported here, and provide satisfactory reconstruction results even for

very large bursts.

We also note that interleaving the image data before packetization avoids loss of contiguous areas in

an image, facilitating reconstruction. This paper demonstrates reconstruction in the transform domain

by expressing the lost data as a linear combination of blocks in the 4-neighborhood of the lost block.

Four optimal weights (coefficients) need to be calculated per block based on combinations of

available adjacent blocks. These weights, which result in a 10% space overhead, are used later in

reconstruction. Strong diagonal edges are not well reconstructed by this method. Additional work on

the reconstruction of missing data in block-based compression schemes is reported in, where the DCT

coefficients of a missing block are interpolated from those with the same position in the neighboring

blocks. The novelty of our proposed scheme is in the separation of the lost blocks into different

classes, followed by the use of state-of-the-art image filling-in algorithms for textured and structured

regions. This is done in a complete automatic fashion and without any side information.

A. Image Inpainting

Structure in an image can be an edge between two regions or the deterministic change in color or gray

level. When the structure is classified in block classification then that pixel is replaced by digital

image in painting method given by [4]

In this method let Ω be the region to be filled and ∂Ω be its boundary. The basic idea is to smoothly

distribute the information around Ω. Both the gray value and the isophote direction are distributed

within the boundary. Let the image is denoted by I then we can distribute the values by using the

partial differential equation given as

∆I .

Where ,∆ and are gradiant ,laplacian and orthogonal gradiant(isophote direction) respectively.



Fig. 2 Image correction process

III. CONCLUSION AND FUTUREDIRECTIONS

We have proposed a new technique for the filling-in of missing blocks in wireless transmission of

JPEG (or block based) compressed images. We have shown that as long as the features in the image

are not completely lost, they can be satisfactorily reconstructed using a combination of

computationally efficient image inpainting and texture synthesis algorithms. This eliminates the need

for retransmission of lost blocks. When image resolution is increased, the quality of reconstruction

improves & retransmission request is rarely required. We have tried to use image dependent

information i.e. texture and structure to enhance the performance of JPEG. The compression ratio can

be further increased by finding better masks by providing more image information. Missing blocks in

the different channels need not be in the same image used in block classification &

reconstruction .Adding this to current neighbouring information used is expected to improve even

further the quality of results.



REFERENCES

[1] E. Chang, “An image coding and reconstruction scheme for mobile computing,” in Proc. 5th

IDMS, Oslo, Norway, Sept. 1998, pp. 137–148.

[2] S. S. Hemami, “Digital image coding for robust multimedia transmission,” in Proc. Symp.

Multimedia Communications and Video Coding,New York, 1995.

[3] M. Bertalmio, G. Sapiro, V. Caselles, and C. Ballester, “Image inpainting,” in Computer Graphics

(SIGGRAPH 2000), July 2000, pp. 417–424.

[4] A. A. Efros and T. K. Leung, “Texture synthesis by nonparametric sampling,” in IEEE Int. Conf.

Computer Vision, Corfu, Greece, Sept. 1999,pp. 1033–1038.

[5] C. Ballester, M. Bertalmio, V. Caselles, G. Sapiro, and J. Verdera, “Filling-in by joint

interpolation of vector fields and gray levels,” IEEETrans. Image Processing, to be published.

[6] T. Chan and J. Shen, “Mathematical models for local deterministic inpaintings,” UCLA CAM

Rep., Mar. 2000.

[7] D. Heeger and J. Bergen, “Pyramid based texture analysis/synthesis,” in Proc. SIGGRAPH 1995,

July 1995, pp. 229–238.

[8] S. Masnou and J. Morel, “Level-lines based disocclusion,” in IEEE Int. Conf. Image Processing,

Oct. 1998.



CYBER SECURITY Mandar Tawde, Pooja Singh, Maithili Sawant, Girish Nair

Information Technology, Government Polytechnic Mumbai 49, Kherwadi Ali Yawar Jung Marg, Bandra (E), Mumbai-400051, India

[email protected], [email protected]

Abstract

This document gives information about Hacking. Some Types of hacking, some tools of hacking

and some preventive measures in order to stop hacking. It will help every computer user for the

security of his system. As hacking is very upcoming and serious problem for many fields, the study

of cyber security is important.

Keywords - The best way of offending is defending

I. WHY HAVE WE OPT CYBER SECURITY ?

Hacking is hot and rapid growing national problem for which the market may fail to make a solution

because individuals often select less than optimal security levels in a world of positive transaction

cost.

II. SCANDALOUS HACKINGS To show the seriousness of hacking we have included some very scandalous hacking incidences.

A. 1960s

The Dawn of Hacking

The advent of 1st computer hacking emerged at MIT. They were the group of people, who forcefully

entered into model train group and began to hack the electrical trains, tracks and switches to make

them perform faster and differently. But few due to their curiosity became typical hacker.

B. 1995

The Mitnick Takedown

Serial cyber trespasser Kevin Mitnick is captured by federal agents and charged with stealing 20,000

credit card numbers.

C. 1998

The Cult of Hacking and the Israeli Connection

The hacking group Cult of the Dead Cow releases its Trojan horse program, Back Orifice—a

powerful hacking tool--at Def. Con. Once a hacker installs the Trojan horse on a machine running

Windows 95 or Windows 98, the program allows unauthorized remote access of the machine.

D. 1999



E. Havoc of Mellisa virus

Mellisa virus hit Microsoft and other big company which lead them to temporarily terminate their e-

mail systems.

III. WHAT IS CYBER SECURITY? Cyber security is the body of technologies, processes and practices designed to protect networks,

computers, programs and data from attack, damage or unauthorized access.

IV. HACKING • Hacking is a process to bypass the security mechanisms of an information system or network.

• In common usage, hacker is a generic term for a computer criminal, often with a specific specialty

in computer intrusion. While other definitions peculiar to the computer enthusiast community

exist, they are rarely used in mainstream context.

• Hacking is an unauthorized use of computer and network resources. (The term "hacker" originally

meant a very gifted programmer. In recent years though, with easier access to multiple systems, it

now has negative implications.)

V. TYPES OF HACKING

Fig 1 Security Incidents reported during 2009

A. Computer Hacking

Computer hacking is the practice of modifying computer hardware and software to accomplish a goal

outside of the creator’s original purpose.



Types of Computer Hackers-There are two types of computer hackers.

• Attitude

• Purpose

B. Password Hacking

• Password hacking is the process of recovering secret password from data that has been stored

in or transmitted by a computer system.

• Password hacking can help a legitimate user retrieve a forgotten password.

• System administrators may use password hacking as a preventive tactic, to check for easily

hacked passwords in order to modify them for increased security.

• Unauthorized users hack passwords to gain access to a secure system.

C. Phishing

• Its art of managing the victim to access a duplicate web pages

• Phishing is a way of attempting to acquire information such as usernames, passwords, and

credit card details by masquerading as a trustworthy entity in an electronic communication.

Phishing is typically carried out by e-mail spoofing or instant messaging and it often directs

users to enter details at a fake website whose look and feel are almost identical to the

legitimate one.

• Case study: eBay, yahoo.

D. Virus and worms

Viruses and worms are self-replicating programs or code fragments that attach themselves

to other programs (viruses) or machines (worms). Both viruses and worms attempt to shut

down networks by flooding them with massive amounts of bogus traffic, usually through e-

mail.

VI. TOOLS OF HACKING

A. RAT

• RAT is a remote administration tool or Remote Access Trojan

• It gives the admin privileges to the attacker

B. NetCat

• Netcat has been dubbed the network Swiss army knife.

• It is a simple Unix utility which reads and writes data across network connections, using TCP

or UDP protocol



• Netcat is designed to be a dependable “back-end” device that can be used directly or easily

driven by other programs and scripts. At the same time, it is a feature-rich network debugging

and investigation tool; since it can produce almost any kind of correlation you would need and

has a number of built-in capabilities.

• Its list of features includes port scanning, transferring files, and port listening, and it can be

used as a backdoor.

C. Ethereal

• Ethereal is a free network protocol analyzer for UNIX and Windows.

• Ethereal has several powerful features, including a rich display filter language and the ability

to view the reconstructed stream of a TCP session.

D. NetBus

Netbus is programmed software which requires, a device which looks like this.

This devise is attached at the ports. This method is used for getting passwords, banking details, etc.

• In 1999, Net Bus was used to plant child pornography on the work computer of a law scholar

at Lund University. The 3,500 images were discovered by system administrators, and the law

scholar was assumed to have downloaded them knowingly. He lost his research position at the

faculty, and following the publication of his name fled the country and had to seek

professional medical care to cope with the stress. He was acquitted from criminal charges in

late 2004, as a court found that Net Bus had been used to control his computer.

VII. PREVENTIVE MEASURES.

To Prevent Hacking we should use:-

A. Anti-viruses

In order to damage our security system hackers generally try to send malwares, spam wares, etc.

Antivirus is best tool to defend their access in our system.

B. Eraser



Eraser is an advanced security tool (for Windows), which allows you to completely remove

sensitive data from your hard drive by overwriting it several times with carefully selected patterns.

Works with Windows 95, 98, ME, NT, 2000, XP and DOS. Eraser is free software and its source

code is released under GNU General Public License.

C. Firewall

One way of being warned that malware has infected your machine is by using a software firewall

(this also works well for viruses too). When a software firewall catches a program trying to make a

connection, it will alert you, give you the name of the program, and ask if you want to block it

from the Internet.

VIII. INFERENCE

If with a few advancements in the way we are using the internet we can avoid a big threat and make

web a safer place. Some of them would be

• Using a good proxy server

• Using vulnerability testers like nmap

• Limiting the number of open ports

IX. ACKNOWLEDGMENT

Cyber security has become an important part of our life. We have nurtured it from last days and while

doing so we received in addition the compliments a lot of suggesting from publisher, authors, and

professors.

REFERENCES

[1] Vaidihi and Gaurav “Hacker5”ed.2nd.

[2] Ankit Fadiya-“Ethical hacking” ed.2d.

[3] The google website. www.google.org

[4] The Wikipedia website. www.wikipedia.org



BRAIN GATE Shruti Kotian, Sonal Karkhanis, Shivang Menon

Department of Computer Science, SIES GST, Nerul, Navi Mumbai, India

[email protected]

Abstract

As the power of modern computers grows alongside our understanding of the human brain, we move

closer to making some pretty spectacular science fiction into reality. Consider the potential to

manipulate computers or machinery with nothing more than a thought! Thousands of people around

the world suffer from paralysis and loss of other bodily movement, rendering them dependent on others

to perform even the most basic tasks. The mind-to-movement system that allows a quadriplegic man to

control a computer using only his thoughts is a scientific milestone. This is the BRAIN GATE system.

Brain gate system is based on ‘Cyber kinetics’ platform technology to- sense, transmit, analyze and

apply the language of neurons. A computer chip, which is implanted into the brain, monitors brain

activity in the patient and converts the intention of the user into computer commands. It would be a

huge therapeutic application for people who have seizures, which leads to the idea of a ‘pacemaker for

the brain’.

Keywords: BCI (Brain-Computer Interface), motor cortex.

I. INTRODUCTION

The principle of operation of the brain gate neural interface system is that with intact brain function,

neutral signals are generated even though they are not sent to the arms, hands and legs. These signals are

interpreted by the system and a cursor is shown to the user on a computer screen that provides an alternate

“Brain Gate pathway”. The user can use that cursor to control the computer, just as a mouse is used. A

brain-computer interface (BCI) which is a direct communication pathway between a human (brain cell

culture) and an external device, serves this purpose.

II. WORKING

The Brain Gate device consists of a tiny chip that is surgically implanted in the brain's motor cortex. The

chip can read signals from the motor cortex, send that information to a computer via connected wires,

and translate it to control the movement of a computer cursor or a robotic arm. However, because

movement carries a variety of information such as velocity, direction, acceleration and as the BCI is only



reading signals from a small sample of those cells, the initial control of a robotic hand may not be as

smooth as the natural movement of a real hand. But with practice, the user can refine those movements

using signals from only that sample of cells.

Advantages:

• It’s potential to interface with a computer without weeks or months of training.

• It’s potential to be used in an interactive environment, where the user's ability to operate the

device is not affected by their speech, eye movements or ambient noise.

• The ability to provide significantly more usefulness and utility than other approaches by

connecting directly to the part of the brain that controls hand movement and gestures.

Disadvantages:

• The switches must be frequently adjusted which is a time consuming process. As the device is

perfected this will not been issue.

• There is also a worry that devices such as this will “normalize” society.

• The Brain Gate Neural Interface System has not been approved by the FDA, but has been

approved for IDE status, which means that it has been approved for pre-market clinical trials.

• Limitation in information transform rate. The latest technology is 20 bits/min.

III. CONCLUSION

Medical cures are unavailable for many forms of neural and muscular paralysis. Thus, the idea of

moving robots or prosthetic devices not by manual control, but by mere “thinking” is a major

scientific milestone in the history of mankind!

IV. CURRENT WORK PROGRESS

Brain Gate is currently recruiting patients with a range of neuromuscular and neuron-degenerative

conditions for pilot clinical trials being conducted under an Investigational Device Exemption (IDE)

in the United States. Cyber kinetics hopes to refine the Brain Gate in the next two years to develop a

wireless device doesn’t have a plug, making it safer and less visible. And once the basics of brain

mapping are worked out, there is potential for a wide variety of further applications.

REFERENCES



[1] Levine, SP; Huggins, JE; Bement, SL; Kushwaha, RK; Schuh, LA; Rohde, MM; Passaro, EA; Ross,

DA et al. (2000). "A direct brain interface based on event-related potentials". IEEE transactions on

rehabilitation engineering: a publication of the IEEE Engineering in Medicine and Biology Society.

[2] Miguel Nicolelis et al. (2001) Duke Neurobiologist has developed system that allows monkeys to

control robot arms via brain signals.

[3] http:// www.howstuffworks.com

[4] http:// www.wikipedia.org



SPEED CONTROL MECHANISM USING TERRAIN DETECTIONAnkit Nanavaty, Ruchi Patel, Ankit Kandoi

Dept. of Computer, MCT’s Rajiv Gandhi Institute of Technology, Mumbai, India


Abstract

Information of texture to distinguish between the types of terrains in the environment are not defined

by clear boundaries. In this paper we illustrate that an image consists of a composite texture of regions.

Using Image Processing Algorithms, the type of the terrain is identified, and accordingly the

appropriate velocity of the robot is derived, so that the robot can traverse over that particular terrain.

It’s a real time process, and the speed of the robot changes with a change in the terrain in the

environment.

A video camera will be mounted on the robot, with a similar perspective to the driver, which takes the

video of the road, with different classes of textures when the car is in motion. These textures (loose

stones, grass, ground, concrete, asphalt, slopes) will then be processed using Image Processing

Algorithms. Based on the results obtained after applying the algorithms, the velocity estimations are

done and the speed of the robot changes accordingly.

Keywords- Wavelet transform; WCF; FIS

I. INTRODUCTION

Navigation with vehicles in unknown environments is an easy task for humans, but very difficult for

robots [3]. For autonomous navigation in outdoor terrains, the robot must be endowed with the ability to

interpret data acquired from its environment so as to plan and follow trajectories from its current location

to the desired location, considering the features of the terrains [3].

Most autonomous navigation works have focused on the problem of recognition and avoidance of

obstacles; however, so far, almost no attention has been placed on the recognition of terrains' textures and

irregularities, and how they accept the performance and safety of robots during navigation. Autonomous

off-road robots will be employed in military operations, and also in civilian applications such as wide-

area environment monitoring, disaster recovering, search-and-rescue activities, as well as planetary

exploration. [1]. There is a strong push in the Army to move towards autonomous and semi-autonomous

vehicles to perform tasks which may be too cumbersome or dangerous for human driven vehicles to

perform. Unmanned ground vehicles (UGVs) can potentially be used to find and disarm improvised

explosive devices (IEDs) without risking the lives of soldiers [2].



The right navigating velocity regarding the terrain features is a requisite to keep robots away from risks of

falling and sliding due to surface slopes or smash textures, the vehicle velocity must be updated according

to the terrain features in order to guarantee robots safe navigation. For wheeled-robots navigation on

different terrains, it is necessary to have required information about the surface features [3]. One of those

features on which this work focuses is the surface roughness on which the vehicle is moving. The terrain

is the principle source of chassis excitation in off-road vehicles and the control of the vehicle is dependent

on effectively characterizing the terrain slope, roughness, and surface condition [2]. The robot's velocity

during real navigation depends on the terrain roughness; moreover, the robot integrity depends on the

right velocity of the robot while navigating through terrain.

The information of environment needs to be quickly and accurately processed by the robot's navigation

systems for a right displacing. The velocity setting must be performed remotely, i.e. the robot must detect

and classify soft irregularities and textures before the robot passes on them, so that the robot disposes

enough time to react and set its velocity according to the terrains' characteristics [3]. On the other hand,

by extending the robots' abilities to recognize the terrains' features and then, accordingly, update the

velocity while navigating, the usage of the robots' energy and computing resources would improve as well

as the autonomy would be strengthen.

During navigation, the robot can move on irregularities under the following criteria; if irregularities are

soft (slopes with inclination less than or equal to 15 degrees), then the robot can move over them;

otherwise, the non-soft irregularities (slopes with inclination bigger than 15 degrees) are considered as

slopes, slope detection algorithms need to be applied and velocity of the robot must be adjusted

accordingly.

II. PROPOSED SPEED CONTROL SYSTEM

A. Algorithm

• A wireless camera is mounted on the robot (vehicle) which captures the video and transmits it the

Processing end (PC).

• This video is converted into image frames for further processing.

• The first frame is taken and the Texture Segmentation Algorithm (Texture Segmentation using

Wavelet Transform) is applied. Thus we obtain various segments of the processed image.

• The Wavelet Co-occurrence Feature (WCF) values of each segment in the image, is calculated. WCF

values give the features of the segments such as contrast, cluster, shade and cluster prominence,

brightness and the relationship between them [5]. According to these WCF values, the speed of the

robot is adjusted.



Figure 1. Flow of the Speed Control System



• If the WCF value is greater than the maximum threshold, it implies maximum roughness, and thus we

vary the robot speed to the minimum value for safe navigation. If the WCF value is less than the

minimum threshold, it implies minimum roughness, and thus we vary the robot speed to the

maximum value for safe navigation.

• Hence, the robot motion takes place with the calculated speed, where the change in speed is

calculated considering the difference in textures of the terrain.

• This process is continued till all the frames are processed and the speed of the robot is detected for the

whole path.

II. DISCRETE WAVELET TRANSFORM

A. Definition

Discrete Wavelet Transform (DWT) is performed in the frequency domain, where the input image is

decomposed to different frequency levels using the Discrete Wavelet Frames (DWF). Few statistical

methods have been proposed in the past for texture analysis. Inherent disadvantages with those

approaches, such as increased computational cost and irreversibility, can be eliminated using the wavelet

transform [4].

Wavelets are functions generated from one single function W by dilations and translations. The basic idea

of the wavelet transform is to represent any arbitrary function as a superposition of wavelets [5]. Any

such superposition decomposes the given function into different scale levels where each level is further

decomposed with a resolution adapted to that level. The discrete wavelet transform (DWT) is identical to

a hierarchical sub band system where the sub-bands are logarithmically spaced in frequency and represent

octave-band decomposition. By applying DWT, the image is actually divided i.e., decomposed into four

sub-bands and critically sub-sampled [5]. These four sub bands arise from separate applications of

vertical and horizontal filters. The sub-bands labeled LH1, HL1 and HH1 represent the finest scale

wavelet coefficients i.e., detail images while the sub-band LL1 corresponds to coarse level coefficients

i.e., approximation image. To obtain the next coarse level of wavelet coefficients, the sub-band LL1 alone

is



Figure 2. Discrete Wavelet Transform

further decomposed and critically sampled. This results in two-level wavelet decomposition. Similarly, to

obtain further decomposition, LL2 will be used. This process continues until some final scale is reached.

The values or transformed coefficients in approximation and detail images (sub-band images) are the

essential features, which are as useful for texture discrimination and segmentation. Since textures, either

micro or macro, have non-uniform gray level variations, they are statistically characterized by the values

in the DWT transformed sub band images or the features derived from these sub-band images or their

combinations. In other words, the features derived from these approximation and detail sub-band images

uniquely characterize a texture. The features obtained from these DWT transformed images give the

segmented images.

B. Advantages over Fourier Transform

Although the Fourier transform has been the mainstay of transform-based image processing since the late

1950s, a more recent transformation, called the wavelet transform, is now making it even easier to

compress, transmit, and analyze many images. Unlike the Fourier transform, whose basis functions are

sinusoids, wavelet transforms are based on small waves, called wavelets, of varying frequency and

limited duration [6]. A wavelet is a waveform that is bounded in both frequency and duration [8]. This

allows them to provide the equivalent of a musical score for an image, revealing not only what notes (or

frequencies) to play but also when to play them. Conventional Fourier transforms, on the other hand,

provide only notes or frequency information; temporal information is lost in the transformation process.

Most real world signals (such as music or images) have a finite duration and abrupt changes in frequency.

This makes wavelet transform more efficient [8].

III. TEXTURE SEGMENTATION The study of terrain vehicle interaction has been a topic which has been researched for quite some time.

Researchers have used it to refer to understanding the mechanical properties of the terrain called terra-

mechanics. The terrain segmentation problem is to assign a class label to each pixel of an image based on

the properties of the pixel and its relationship with its neighbourhoods [10]. Determining how the terrain

properties affect a vehicle’s ability to traverse it, which has also been referred to as traffic ability. It has

also been used to describe the process of classifying the type of terrain (i.e. sand, dirt, gravel). The

segmentation process is a joint detection and estimation of the class labels and shapes of the regions with

homogeneous statistical properties [10]. One will also see the term terrain segmentation used for larger

scales than relevant for vehicle dynamic studies, such as in geological surveys or aerial vehicle mapping.

Many of these works use Digital Elevation Models (DEM) to represent the terrain. Thus, the literature



presented here will include terrain segmentation as it relates to mechanical properties, small ground

robots, and larger ground vehicles.

Here, texture mosaic images of size N x N are considered [4]. The analysis is carried out by considering

sub images (i.e., block) of size 32 x 32. Each 32 x 32 sub-image, taken from top left corner of the original

image, is decomposed using one level DWT and co-occurrence matrices (C) are derived for sub-image.

Fig. 2 (a) shows the level 1 decomposition (i.e., LL1, LL2, LL3, LL4) and fig. 2 (b) shows the level 2

decomposition with detail sub-bands (i.e., LL2, LH2, HL2 & HH2 sub-bands) of wavelet decomposed

sub-image. Then, from these co-occurrence matrices (C), significant WCFs, such as contrast, cluster

shade and cluster prominence, are computed using formulae given, as texture features [3]. In our

implementation, the contrast feature values, calculated over all the blocks, are subjected to linear

normalization in the scale of 0–255, while the cluster shade and cluster prominence features, which found

to have very large dynamic ranges, are subjected to logarithmic normalization in the scale of 0–255 for

computation [5].

A. Segmentation Algorithm

Input : Texture mosaic image of size N x N.

Output: Texture segmented image.

Step 1. Read the texture mosaic image.

Step 2. Obtain 32 x 32 sub-image blocks, starting from the top left corner.

Step 3. Decompose sub-image blocks using 2-D DWT.

Step 4. Derive co-occurrence matrices (C) for original image, and detail sub-bands of DWT

decomposed sub image blocks.

Step 5. Calculate WCFs such as contrast, cluster shade and cluster prominence from co- occurrence

matrices.

Step 6. Calculate the difference between sums of WCFs of adjacent sub-image blocks. This

results in segmentation band.

Step 7. Apply disk filtering and thresholding techniques to remove noise like artifacts if any in the

segmentation band.



Figure 3. Flow Chart of Texture Segmentation Algorithm

Step 8. Apply skeleton extraction algorithm to get thinned or segmented line of one pixel thickness.

Fig. 3 shows the Flowchart of the Texture Segmentation Algorithm. The texture segmentation is carried

out by comparing the normalized co-occurrence features of discrete wavelet transformed adjacent but

overlapping 32 x 32 sub-image blocks, both horizontally and vertically [4]. Each successive block is

differ from the previous one in its spatial location by one column or one row, depending on whether the

successive block is taken in horizontal or vertical direction, respectively. Here, the sum of the above

normalized features of one block is compared with the corresponding sum of features derived from the

next block. The difference in feature values is less when successive blocks belong to the same texture

region and it increases in the texture border region while it is high when the successive blocks are from

two different texture regions.

By carrying out the above block by block feature comparison both in horizontal and vertical directions; a

segmentation band is formed across the texture boundaries [9]. When the difference in feature values

within the same texture region is high, noise like artifacts or spurious spots appear in the segmented

image. This spurious spots are removed by applying disk filtering and thresholding techniques (i.e., post

processing). Then, the post processed segmented band is thinned using skeleton extraction algorithm to

get segmented line of one pixel thickness [9]. The thinned result gives the line of demarcation among the

different textures present in the image i.e., thinned lines are exactly aligned with texture boundaries.

B. Advantages over Other Algorithms

More recently, methods based on multi-resolution or multi-channel analysis, such as Gabor filters and

wavelet transform,



have received a lot of attention. But, the outputs of Gabor filter banks are not mutually orthogonal, which

may result in a significant correlation between texture features [5]. Finally, these transformations are

usually not reversible, which limits their applicability for texture synthesis.

Most of these problems can be avoided if one uses the wavelet transform, which provides a precise and

unifying frame work for the analysis and characterization of a signal at different scales (e.g., Unser,

1995). Another advantage of wavelet transform over Gabor filter is that the low pass and high pass filters

used in the wavelet transform remain the same between two consecutive scales while the Gabor approach

requires filters of different parameters. In other words, Gabor filters require proper tuning of filter

parameters at different scales.

One advantage of the wavelet transform over the histogram processing is that in many cases, a large

number of the detail coefficients turn out to be very small in magnitude [7]. Truncating these small

coefficients from the representation introduces only small errors in the reconstructed signal. We can

approximate the original data distribution effectively by keeping only the most significant coefficients [7].

IV. VELOCITY ESTIMATION

It is proposed to imitate the human perception by employing an approach for velocity updating. Hence, to

imitate the human experience for terrain recognition and the corresponding velocity adjustments when

driving, the choice of an adequate method for recognizing the surface average appearance, without lost in

unnecessary terrain details, is clever for outdoors navigation.

In Earth exploration missions, where human life could be in danger, autonomous rovers are required for

explosive landmines search, deep sea exploration, or to determine the eruption risk when exploring active

volcano craters, as well others [2]. In these dangerous circumstances, the high autonomy of robots

strengthens the robotic support to human safety. On the other hand, by extending the robots' abilities to

recognize the terrains' features and then, accordingly, update the velocity while navigating, the usage of

the robots' energy and computing resources would improve as well as the autonomy would be strengthen.



V. ANALYZING THE RESULTS

Figure 4. Fuzzy Inference System for Speed Control Mechanism

The Fig 4. shows the Fuzzy Inference System for the system Speed Control Mechanism Using Terrain

Detection. As shown, it has one input, namely texture and one output, namely speed. The mamdani model

is used to create the FIS.

Figure 5. Input Membership function plot- Texture

Fig. 5 shows the input (texture) membership function plot with the descriptors as smooth, rough and

very_rough. The values of texture are based on the sum of the WCF values calculated and it ranges from

2 to 3. The range of values for the three descriptors is as shown in the fig. 5.



Figure 6. Output Membership function plot- Speed

Fig. 6 shows the output (speed) membership function plot with the descriptors stop, medium and high.

The range of values that speed can take is from 0 rpm to 100 rpm. The range of values that the three

descriptors can take is as shown in the fig. 6.

Fuzzy If then Rules:

1. If (Texture is smooth) then (Speed is high) (1)

2. If (Texture is rough) then (Speed is medium) (1)

3. If (Texture is very_rough) then (Speed is stop) (1)

VI. CONCLUSIONS

• In this project, for texture segmentation, the concept of discrete wavelet transform is presented for

applying to textured images for decomposing them into detail and approximation regions.

• Co-occurrence features, computed out of the wavelet decomposed images, are used for texture

segmentation.

• The idea behind this proposed method is to exhibit the usage of co-occurrence features computed

from discrete wavelet transformed images (i.e., WCF) for texture segmentation.

• The features are approximately the same when the windows or sub images considered are from the

same texture and different if they are from different textures.

• Varieties of textures, collected from standard album, are stitched to form target images which are

used for experimentation and it is found that the proposed method yield better results than the texture

spectrum method, a single resolution technique

• Appearance-Based recognition algorithms successfully classify terrain textures by regarding the

average appearance.

• The algorithms are computationally inexpensive and easy implementation.



• The low computational cost to process the information acquired from the environment allows

establishing that a car, at a certain speed, can have enough time to react to the roughness changes of

the terrain.

• The wavelet based algorithm for wheeled-robots allows a meta-classification of textures and soft

irregularities used for the terrains' roughness recognition.

• The wavelet based algorithm allows velocity updating by outdoor terrains navigation.

• The average appearance of the terrains' textures, according to experimental results, is the requisite for

velocity updating purpose on outdoor terrains navigation.

• By applying robot velocity updating by regarding the terrains' roughness, the experimental results

show the precision improvement.

• Thus, by using the wavelet based texture recognition method and slope detection, we can ensure safer

navigation of the robots on an unknown terrain.

VII. ACKNOWLEDGMENT We would like to express our gratitude towards Dr. Udhav Bhosle, Principle, Rajiv Gandhi Institute of

Technology, Prof. S.B. Wankhade, HoD, Computer Engineering for providing us with the wonderful

opportunity. We are very grateful towards Mr. Swapnil Gharat, our guide and mentor, for his valuable

suggestions and input towards the betterment of this paper.

REFERENCES

[1] “Reactive speed control system based on terrain roughness detection” by Mattia Castelnovi,

Laboratorium Dist., University of Genova; Ronald Arkin, College of Computing Georgia Institute

of Technology; Thomas R Collins, School of ECE/GTRI, Georgia Institute of Technology

[2] “Terrain characterization and roughness estimation for simulation and control of unmanned

ground vehicles” by Jeremy James Dawkins -December 12, 2011.

[3] “Wheeled-robot’s velocity updating and odometry based localization by navigating on outdoor

terrains” by M. en C. Farid García Lamont. Thesis advisor: José Matías Alvarado Mentado-

November 2010.

[4] “Unsupervised texture segmentation using discrete wavelet frames” by S. Liapis, N. Alvertos, and

G. Tziritas Institute of Computer Science - FORTH, and, Department of Computer Science,

University of Crete, P.O. Box 1470, Heraklion, Greece.

[5] “Texture segmentation using wavelet transform” by S. Arivazhagan, Department of Electronics

and Communication Engineering, Mepco Schlenk Engineering College, Amathur (P.O.), Sivakasi

626 005, Tamil Nadu, India; L. Ganesan, Department of Electronics and Communication



Engineering, Mepco Schlenk Engineering College, Amathur (P.O.), Sivakasi 626 005, Tamil

Nadu, India, 4 February 2003; received in revised form 31 July 2003.

[6] “Digital image processing”, Second Edition by Rafael C. Gonzalez and Richard E. Woods.

[7] “Wavelet-based histograms for selectivity estimation” by Yossi Matias, Department of Computer

Science Tel Aviv University, Israel: Jerey Scott Vittery Department of Computer Science, Duke

University; Min Wangz Department of Computer Science,Duke University.

[8] “Design of feature extraction in content based image retrieval (CBIR) using color and texture”,

Swati V. Sakhare & Vrushali G. Nasre Dept. of Electronics Engg., Bapurao Deshmukh College

of Engg., Sevagram, Wardha (India).

[9] “Wavelet based image segmentation”, Andrea Gavlasová, Aleˇs Procházka, and Martina

Mudrová Institute of Chemical Technology, Department of Computing and Control Engineering.

[10] “Image segmentation using wavelet domain classification”, Hyeokho Choi and Richard Baraniuk,

Department of Electrical and Computer Engineering, Rice University, Houston, Tx77005, USA.



WIRELESS EQUIPMENT CONTROL

Sarang Sutavani, Pratik Borhade, RohitChoudhary, Milan Bhanushali

Electronics Department, Shah & Anchor Kutchhi Engineering College, Mumbai, India

[email protected]

Abstract

This paper aims at presenting the concept of wireless equipment control using microcontroller and

ZigBee, the name of a specification for a suite of high level communication protocols using small, low-

power digital radios based on the IEEE 802.15.4-2006 standard for wireless personal area networks

(WPANs), such as wireless headphones connecting with cell phones via short-range radio. The

technology is intended to be simpler and less expensive than other WPANs, such as Bluetooth. ZigBee

is targeted at radio-frequency (RF) applications that require a low data rate, long battery life, and

secure networking.

Keywords - ZigBee, AT89C51 Microcontroller, RX-434 radio receiver, TRX-434 radio transmitter, ULN

2003 relay driver, CD4519 multiplexer.

I. INTRODUCTION

Here is a microcontroller based wireless equipment controller that can switch on or off devices depending

on the switch pressed by the user in the transmitter section. The devices can be controlled remotely from a

certain distance having range up to few meters depending on the transmitter used. In the transmitter, an

LCD module is used to show the device name which are currently on. The 8-bit AT89C51

microcontroller is the main controlling part of the transmitter section. It is connected to the LCD module,

input switches and encoder. The device control program is stored in the memory of the microcontroller to

control the devices as per the pressing of input switches. The RF transmitter module uses a digital

modulation technique called ASK (Amplitude Shift Keying) or on-off keying. The radio receiver module

receives the ASK signal from the transmitter. The decoder IC demodulates the received address and data

bits. Concepts of wireless RF communication and automation with AT89C51 microcontroller are used

here. Another transmitter and receiver module is designed using ZigBee technology for comparative

study. In this module instead of AT89C51 microcontroller based receiver a ZigBee transmitter and

receiver based equipment controller is designed, which is based on IEEE 802 standard for personal area

networks and operates in 2.4GHz (ISM) radio bands.

II. TRANSMITTER SECTION



Microcontroller is the heart of the circuit. The control logic can be implemented using an assembly

language or high level C language. Both languages have their own advantages. Assembly language

provides a high level of security but is difficult to implement logic. On the other hand, in C language

implementation of logic becomes very simple but there is no sense of security.

The Encoder used here is HT12E IC. It is an 18-pin DIP package encoder IC that encodes 4-bit data and

sends it to the TRX-434 transmitter module. In this project we have used a TRX-434 transmitter module.

The TRX -434 RF transmitter module uses a digital modulation technique called ASK (Amplitude Shift

Keying) or on-off keying. In this technique, whenever logic ‘1’ is to be sent, it is modulated with carrier

signal (434 MHz). This modulated signal is then transmitted through the antenna.

The microcontroller reads the input data from the switches and displays it on the LCD. One of the Ports

provides as read data to the encoder IC HT12E. The microcontroller is programmed to control the input

and output data. When the push button switches are open, logic ‘0’ is constantly fed to the respective port

pins to the microcontroller. When any of the buttons is pressed, logic ‘1’ is fed to the respective port pin

of the microcontroller.

The device control program stored in the memory of the microcontroller activates and executes as per the

functions defined in the program for respective input switches.Data inputs of HT12E are connected to the

microcontroller. The encoder will send the serial stream of pulses containing the address and data to the

data input pin of the TRX RF module.



When a key is pressed it executes the device control program sub routine in the microcontroller and the

program automatically sends the data to encoder IC HT12E. The encoder IC sends the data to (D in) of

the RF transmitter module. The data is transmitted by the TRX- 434 module to receiver section through

antenna.

III. RECEIVER SECTION

The receiver used here is Rx-434 receiver module.The RX-434 radio receiver module receives the ASK

signal from TRX-434.The decoder used in this project is HT12D decoder IC.

The HT12D decoder demodulates the received address and data bits. The multiplexer IC used is CD4519.

IC CD4519 is a quadruple two- input multiplexer that selects appropriate data bits to control the devices.

The o/p current of the multiplexer and the minimum threshold current required for the relay circuit is

different. Hence, we use a relay driver IC ULN2003.The ULN 2003 relay driver consists of seven npn

Darlington pairs that feature high- voltage outputs with common cathode clamps diodes for switching the

inductive loads. The collector –current rating of a single Darlington pair is 500 mA.

The RF receiver circuit (RX- 434) module can receive the signal transmitted by the transmitter from a

distance of upto 9 meters (30 feet). The range can be increased up to 30 meters using a good antenna. D

out pin of RX-434 module is connected to the decoder IC (HT12D).

Decoder IC receives the address and data bits serially from the RF module. Decoder separates data and

address from the received information. It accepts data only if thereceived address matches with the



assigned to the encoder address (HT12E). The HT12D decoder receives serial addresses and data from the

encoder that are transmitted by a carrier signal over the RF medium. The decodercompares the serial

input data three times continuously with its local address. If no error or unmatched codes are found, the

input data codes are decoded and transferred to the output pins. The HT12D provides four latch type data

pins whose data remains unchanged until new data is received. Data pins of the decoder send 4-bit data to

CD4519 multiplexer IC.

This IC CD4519 multiplexer provides four multiplexing circuits with common select inputs; each

contains two inputs and one output. It may be used to selects 4-bit information from one of the two

sources. The latched output data from the multiplexer is fed to the relay driver IC ULN2003, to control

devices through relays.

The system is small, simple and good for wireless equipment control. The devices can be controlled

remotely from the distance up to 30 metres from the transmitter. The RF receiver module can receive the

signal transmitted from a distance up to 9 metres(30feet). The range can be increased up to 30 metres

using a good antenna.

IV. ZIG-BEE

ZigBee is a specification for a suite of high level communication protocols using small, low-power digital

radios based on an IEEE 802 standard for personal area networks. ZigBee devices are often used in mesh

network form to transmit data over longer distances, passing data through intermediate devices to reach

more distant ones. This allows ZigBee networks to be formed ad-hoc, with no centralized control or high-

power transmitter/receiver able to reach all of the devices. Any ZigBee device can be tasked with running

the network.

ZigBee is targeted at applications that require a low data rate, long battery life, and secure networking.

ZigBee has a defined rate of 250 Kbit/s, best suited for periodic or intermittent data or a single signal

transmission from a sensor or input device. Applications include wireless light switches, electrical meters

with in-home-displays, traffic management systems, and other consumer and industrial equipment that

requires short-range wireless transfer of data at relatively low rates. The technology defined by the

ZigBee specification is intended to be simpler and less expensive than other WPANs, such as Bluetooth.

The ZigBee network layer natively supports both star and tree typical networks, and generic mesh

networks.ZigBee is notintended to support power line networking but to interface with it at least for smart

metering and smart appliance purposes.



Now as ZigBee is a transceiver, due to it’s use it is possible here to sendacknowledgement of reception

ofthe signal from receiver to the transmitter. This will help us to determine whether the signal has reached

the destination or not.

With the help of this project we are comparing the two different systems, RF module and ZigBee, which

can be used for the purpose of automation.

V. CONCLUSION

The system is small, simple and good for wireless equipment control. The microcontroller based

equipment controller can switch on or off up to four devices. The devices can be controlled remotely from

the distance up to 30 metres from the transmitter using a good antenna.

With the use of ZigBee, we can send data up to 60 metres. ZigBee is a transceiver, so with a little more

programming it is possible to receiver acknowledgement from the receiver. ZigBee is small, easy to use,

efficient and consumes less power. So, it is perfect for the purpose of Automation.

ACKNOLEDGEMENT

We express our sincere thanks to our project guide Prof. Vidya Gogate for the help and facilities

provided to us for our project. We also thank her for the motivation and guidance which enabled us to

carry out our project work. We are thankful to her for monitoring our progress periodically and helping in

solving our problems during the project work.

We are also grateful to Prof. Uma Rao (Head of Department, Electronics) who provided us the

opportunity to undertake the project. We would like to thank our Principal, Mr. Lande sir, for extending

his support. We would also like to thank our parents for supporting us all the time during the project

work. Last but not the least a vote of thanks to our colleagues and friends who supported us in the due

course of our project.

REFERENCES

1) The 8051 Microcontroller and Embedded Systems - by Muhammad Ali Mazidi, Janice Gillispie Mazidi 2) microcontroller51.blogspot.com 3) www.articlesnatch.com 4) www.alldatasheets.com



5) www.efymag.com 6) Xbee Transreceiver Module - DigiMesh Inc. 7) Getting Started With XBee RF Module - a tutorial by Martin Hebel and George Bricker



IMAGE ENCRYPTION USING ELLIPTIC CURVE CRYPTOGRAPHY

Ashutosh Shukla1, Jay Shah2, Nikhil Prabhu3 Electronics & Telecommunication Engineering Department,

1,2Thakur College of Engineering and Technology, Kandivali(E) , Mumbai-400101 3 St Francis Institute of Technology Borivali (W), Mumbai - 400103

Abstract

This paper deals with encryption of image using Elliptic curve cryptography (ECC).Elliptic curve

cryptography (ECC) is an approach to public key cryptography based on algebraic structure of

elliptic curves over finite fields. Basic ElGamal elliptic curve encryption is used for encryption of

the image. It brings about confidential, authentication and integrity in the exchange of data. The

primary benefit promised by ECC is a smaller key size, reducing storage and transmission

requirements.

Keywords: ECC, domain parameter generation, key pair generation, ElGamal encryption algorithm.

I. Introduction

The way to secure distributed multimedia applications is to encrypt multimedia data using public key

cryptography algorithms. Cryptography means protecting private information against unauthorized

access in that situation where it is difficult to provide physical security [1]. It is science of using

mathematics to encrypt and decrypt data. The basic idea behind the cryptography is that “If it is not

possible to prevent copying of information, it is better to prevent compression.”

II. Elliptic Curve Cryptography(ECC)

Public-key cryptography is based on the intractability of certain mathematical problems. Early public-

key systems, such as the RSA algorithm, are secure assuming that it is difficult to factor a large

integer composed of two or more large prime factors. For elliptic-curve-based protocols, it is assumed

that finding the discrete logarithm of a random elliptic curve element with respect to a publicly-known

base point is infeasible [2]. The size of the elliptic curve determines the difficulty of the problem. It is

believed that the same level of security afforded by an RSA-based system with a large modulus can be

achieved with a much smaller elliptic curve group. Using a small group reduces storage and

transmission requirements.

For current cryptographic purposes and elliptic curve is a plane curve which consists of the points

satisfying the equation (1)

along with a distinguished point at infinity, denoted “∞”. (The coordinates here are to be chosen from

a fixed finite field of characteristic not equal to 2 or 3, or the curve will be somewhat more

complicated)[3].



A. ECC Domain Parameters

The public key cryptographic systems involve arithmetic operations on Elliptic curve over finite fields

which are determined by elliptic curve domain parameters.

The ECC domain parameters over Fq is defined as D = (q, FR, a, b, G, n, h), where

• q: prime power, that is q = p or q = 2m, where p is a prime

• FR: field representation of the method used for representing field elements Fq

• a, b: field elements, they specify the equation of the elliptic curve E over Fq, ax b

• G: A base point represented by G= (xg, yg) on E(Fq ) • n: Order of point G , that is n is the smallest

positive integer such that nG = O

• h: cofactor, and is equal to the ratio #E(Fq)/n, where #E(Fq) is the curve[4].

B. Key Generation

Alice’s (or Bob’s) public and private keys are associated with a particular set of elliptic key domain

parameters (q, FR, a, b, G, n, h).

Alice generates the public and private keys as follows

1. Select a random number d, d [1, n – 1]

2. Compare Q = dG.

3. Alice’s public key is Q and private key is d.

It should be noted that the public key generated needs to be validated to ensure that it satisfies the

arithmetic requirement of elliptic curve public key.[4]

a. ElGamal Elliptic Curve Encryption

Elliptic curve cryptography can be used to encrypt an image, M, into cipher text. The image M is

encoded into a point PM form the finite set of points in the elliptic group, Eq(a,b). The first step

consists in choosing a generator point G Eq(a,b),such that the smallest value of n such that n G=O is

a very large prime number. The elliptic group Eq(a,b) and the generator point G are made public.

Each user select a private key, nA <n and compute the public key PA = nA GA . To encrypt the point

PM for Bob, Alice chooses a random integer k and computes the cipher text pair of points PC using

Bob’s public key PB : PC =[(kG),( PM+kPB )] [5].

III. Results and Conclusions

In this paper, we have presented an application of ECC with Generator G in image encryption. ECC

points convert into cipher image pixels at sender side and decryption algorithm is used to get original

image within a very short time with a high level of security at the receiver side. Elliptic curves are

believed to provide good security with smaller key sizes, something that is very useful in many

applications. Smaller key sizes may result in faster execution timings for the image encryption, which

are beneficial to systems where real time performance is a critical factor ECC can be used into a



security system such as video compression, face recognition, voice recognition, thumb impression,

sensor network, industry and institutions.

References

1. William Stallings, Cryptography and Network Security, Prentice Hall, 4th Edition, 2006.

2. V. Miller, “Uses of elliptic curves in cryptography”, Advances in Cryptology, Springer-Verlog

New York,1986

3. Jeffrey L. Vagle, “A Gentle Introduction to Elliptic Curve Cryptography”,BBN

Technology,Nov21,2010.

4. D.Hankerson, A.Menezes, and S.A. Vanstone, Guide to Elliptic Curve Cryptography, Springer-

Verlag, 2004.

5. ElGamal, T., “A public key cryptosystem and a Signature scheme based on discrete logarithm,”

IEEE Trans. Informn, Theory, IT-31, no.4, pp 469-472, July 1985.



CIRCULAR MICROSTRIP TEXTILE ANTENNA Prof. Kiran Rathod1, PranjalGupta2, Bhavik Janjmera3, Suchit Patel4, Jignesh Bhagat5

Dept. of Electronics and Tele-Communication Engineering,

Mumbai University, Mumbai-400 098, India


Abstract

The speed of technology and its evolution with the help of human efforts and his thinking is growing

like wildfire. Also the man machine relation has further taken forward big technical leaps in the world

of Antenna and Microwave Technology. In near future we will see clothing and textile material to be

lined up for antenna technology and together will be known as “Smart Clothes”. In this paper, circular

microstrip for wearable application is been designed. This wearable is used to meet Bluetooth

specifications and has been developed by using copper conducting parts and electrotextile (smart

clothes). In this case jeans or cotton materials are used.

Keywords—circular patch antenna, wearable antenna, radiation pattern, fabric characterization,gain.

I. Introduction

Advances in communication and electronic technologies have enabled the development of compact and

intelligent devices that can be placed on human body or implanted inside it.The new generation of textile

has the capability to conduct electricity and at the same time is wearable. There are much more

applications involved if an antenna is made that are totally wearable. We use this new property of

conductivity in textile material to implement the wireless functions to clothing. In general, the antennas

are made of metal which are highly conductive and also is solid structured which is fixed and hence give

the stable output. The challenge with textile antenna is that, because the antenna is purely textile with the

radiating element as well as dielectric material and ground being textile, which can be folded and twisted,

output stability is the major factor that should be taken into consideration.There are some applications at

present, where the antennas are used to continuously monitor the biometric data of human body. In order

to do this, they need to be so close to the human body all the time so that they can continuously monitor

the biometric data and send the information to the outside world. If the antenna is hard it is not suitable to

always keep them attached with the human body as they can make some harm due to their physical

structure.



Fig.1. Wearable Antenna

If the antenna is made of textile material they will not make any harm to human body and will be totally

wearable. This is the main motivation This has led humans to introduce special networks called Body

Area Networks (BANs). This BANs will be a great boost in future for many purposes and interested area

being healthcare and emergency services like military applications etc. This antenna is designed to work

at 2.45GHz.A comparison between different textile material and their effect on gain, radiation efficiency

has also been presented The simulation software Zeland IE3D is used to simulate the antennas. This

software uses Method of Moment technique. It solves the entire electromagnetic phenomenon related with

the antenna by using integral method. This approach gives a very accurate simulated result.

II. Antenna Design Procedure

The reason of using circular microstrip antenna is that it occupies less physical area as compared to

rectangular antenna, in application of arrays circular geometry is preferred. The basic structure is shown

in figure 2, comprising of thin conducting circular microstrip on a insulating dielectric substrate backed

by ground plane. Also it necessary to know the exact value of dielectric constant of substrate (textile

material) chosen.

Fig.2. Circular Patch Antenna



Table 1

• Resonance Frequency (fr) = 2.45GHz.

• Height of Substrate (h) = 2.84 mm.

• Relative permittivity (εr) = 1.67.

• Loss Tangent (tan δ) = 0.02.

The resonant frequency for the dominant mode of propagation, in case of circular patch antenna is written

as:

.µ

………………….(1)

The formula for effective radius is,

1 ln 1.7726 / ……........(2)

The effective length can also be calculated by equating the area of circulat microstrip antenna with area of

rectangular antenna. The length L of the RMSA is taken as diameter 2a of the CMSA, which is important

fromthe field variation point of view. The widthWof the RMSA is then calculatedby equating its area with

that of the CMSA, which comes out to be W =πa/2. From the effective dimensions of rectangular

microstrip antenna, ae can be obtained as

………………. (3)

An infinite ground plane is assumed to avoid (i) back lobes in radiation pattern of the antenna, (ii) to

reduce diffraction and scattering effects at the edges of the ground plane and to (iii) minimize the

undesirableeffects of surface waves.

III. Simulation Results

The simulation is carried out between 2 GHz to 3GHz frequency.

A. Farfield Radiation Pattern.

The farfield radiation pattern of circular microstrip antenna is



Fig. 3. Radiation pattern

B. Gain and efficiency

Fig. 4. Gain vs frequency using two different materials.

C. Directivity vs Frequency.

The directive gain obtained is 8.26 dB and power gain is 5.75 dB at design frequency of 2.45 GHz.



Fig. 5. Directivity vs frequency.

D. Efficiency vs frequency.

The efficiency for case 1 is 56.12% and for case 2 is around 50%.

Fig. 6. Efficiency vs frequency.

E. Comparison with other antennas.

For an identical design, Circular microstrip antenna gives similar performance characteristics as that of

rectangular microstrip antenna. The main advantage being that it occupies less physical area as compared

to rectangular microstrip antenna.Various physical parameters for design in Appendix 1.

IV. Conclusion

From the results obtained of this antenna we conclude that a circular microstrip antenna is better option

for wearable applications as it also occupies less physical area. The performance parameters of this



textile antenna is comparable to copper based microstrip antennas and they are easy to build and

drapable.We also conclude that textile microstrip antenna are very good alternatives to standard PCB

substrate antenna for different applications. WEARABLE ANTENNAS ARE THE FUTURE.

References

1. http://gruoper.ieee.org/groups/802/15/

2. Constantine A. Balanis, “Antenna Theory: Analysis and design” Constantine A.Balanis, “ADesign”,

2nd edition, JohnSingapore, pp 722-736, 19.

3. Girish Kumar, K. P. Ray, “Broadband Microstrip Antennas”.

4. www.microwave101.com

5. www.antenna–theory.com

Appendix 1

Physical design parameters

Design Parameters

Antenna # 1

Antenna # 2

Antenna # 3

Antenna # 4

Resonant Frequency

2.45 GHz

2.45 GHz

2.45 GHz

2.45 GHz

Substrate Dielectric Constant

1.51

1.47

1.44

1.48

Substrate Thiclness(mm)

3.0

3.0

2.85

3.0

Loss Tangent Of Substrate

0.02

0.02

0.01

0.02

Materials Used For Ground Plane

and Patch

Copper

Copper

Copper

Copper

Insulating Fabric Material

Employed

Wash Cotton

Curtain Cotton

Polyester

polycot





SIMULATION AND IMPLEMENTATION OF ELLIPTICAL MICRO STRIP ANTENNA AT 750MHZ

Kiran Rathod, Tushar Tanna, Raj Davda, Paresh Prajapati,

K J Somaiyya College of Engineering, Mumbai, India

[email protected],[email protected],[email protected], [email protected]

Abstract

In telecommunication industry, several types of antennas are used. The most common of which are the

micro strip patch antennas (also known as printed antennas) or patch antenna. Patch antennas can be

used in many types of communications links that may have varied requirements. A single patch

antenna provides a maximum directive gain of around 6-9 dBi. We can design it to work at multiple

frequencies. It is available in various shapes and configuration, most common of which is a

rectangular micro strip antenna (RMSA).In this project we are designing single fed annular ring micro

stripantenna. The software used to model and simulate the micro strip patch antenna is ZeelandInc’s

IE3D software. IE3D is a full-wave electromagnetic simulator based on the method of moments. It

analyzes 3D and multilayer structures of general shapes. It has been widely used in the design of

MICs, RFICs, patch antennas, wire antennas, and other RF/wireless antennas. An evaluation version

of the software will be used to obtain the results.

I. Introduction

Microstrip antennas (MSAs) have several advantages, including that they are lightweight and small-

volume and that they can be made conformal to the host surface. In addition, MSAs are manufactured

using printed-circuit technology, so that mass production can be achieved at a low cost.In high

performance aircrafts, spacecrafts, satellites, missiles and other aerospace applications where size, weight,

performance, ease of installation and aerodynamics profile are the constraints, a low or flat/conformal

profile antenna may be required. In recent years various types of flat profile printed antennas have been

developed such as Microstrip antenna (MSA).

MSAs, which are used for defense and commercial applications, are replacing many conventional

antennas. However, the types of applications of MSAs are restricted by the antennas’ inherently narrow

bandwidth (BW). Accordingly, increasing the BW of the MSA has been a primary goal of research in the

field. This is reflected in the large number of papers on the subject published in journals and conference

proceedings. In fact, several broadband MSA configurations have been reported in the last few decades.



II. Overview

The concept of microstrip radiators was first proposed by Deschamps as early as 1953. The first practical

antennas were developed in the early 1970’s by Howell and Munson. Since then, extensive research and

development of microstrip antennas and arrays, exploiting the new advantages such as light weight, low

volume, low cost, low cost, compatible with integrated circuits, etc., have led to the diversified

applications and to the establishment of the topic as a separate entity within the broad field of microwave

antennas.

III. Working of Microstrip Antenna

The patch acts approximately as a calls on the sides). In a cavity, only certain modes are allowed to exist,

at different resonant frequencies. If the antenna is excited at a resonant frequency, a strong field is set up

inside the cavity, and a strong current on the bottom surface of the patch. This produces significant

radiation (a good antenna).

IV. Feeding Technique

The Coaxial feed or probe feed is a very common technique used for feeding Microstrip patch antennas.

As seen from Figure 3.5, the inner conductor of the coaxial connector extends through the dielectric and

is soldered to the radiating patch, while the outer conductor is connected to the ground plane. The main

advantage of this type of feeding scheme is that the feed can be placed at any desired location inside the

patch in order to match with its input impedance. This feed method is easy to fabricate and has low

spurious radiation. However, its major disadvantage is that it provides narrow bandwidth and is difficult

to model since a hole has to be drilled in the substrate and the connector protrudes outside the ground

plane, thus not making it completely planar for thick substrates (h > 0.02λo). Also, for thicker substrates,

the increased probe length makes the input impedance more inductive, leading to matching problems. It is

seen above that for a thick dielectric substrate, which provides broad bandwidth, the microstrip line feed

and the coaxial feed suffer from numerous disadvantages. The non-contacting feed techniques discussed

below, solve these problems.

Fig.1 : Block Diagram



a. Design Procedure

The transmission line model described in chapter will be used to design the antenna.

Step 1: Calculation of Major axis (a): The width of the Micro strip patch antenna is given by equation

(3.6) as:

Substituting c = 3e8 m/s, εr = 4.3and fo = 750 Mhz, we get:

W = 0.122 m = 122.00 mm

Step 2: Calculation of Effective dielectric constant (ε reff): Equation (3.1) gives the effective dielectric

constant as:

Substituting εr = 4.3 , W = 122.0 mm and h = 1.6 mm we get:

εreff = 4.16

Step 3: Calculation of the Effective length (Leff ): Equation (3.4) gives the effective length as:

Substituting, c = 3e8 m/s and f o = 750 MHz we get:

L eff = 0.11554 m = 115.54 mm

Step 4: Calculation of the length extension ( ΔL ): Equation (3.2) gives the length extension as:

Substituting εref f = 4.16, W = 122.0 mm and h = 1.6 mm we get:

ΔL = 0.771528 mm



Step 5: Calculation of actual length of patch ( L ): The actual length is obtained by re-writing equation

(3.3) as:

L= Leff −2Δ L

Substituting L eff = 115.54 mm and ΔL = 0.771528 mm

we get: L = 0.114 m = 114.00 mm = 2a

Step 6: Calculation of Minor axis (b): The width of the Micro strip patch antenna is given by equation

(3.6) as:

Substituting c = 3e8 m/s, εr = 4.3and fo = 900 Mhz, we get:

W = 0.102 m = 102.00 mm

Step 7: Calculation of Effective dielectric constant (ε reff): Equation (3.1) gives the effective dielectric

constant as:

Substituting εr = 4.3 , W = 122.0 mm and h = 1.6 mm we get:

εreff = 4.15

Step 8: Calculation of the Effective length (Leff ): Equation (3.4) gives the effective length as:

Substituting, c = 3e8 m/s and f o = 750 MHz we get:

L eff = 0.09543 m = 95.43 mm

Step 9: Calculation of the length extension ( ΔL ): Equation (3.2) gives the length extension as:



Substituting εref f = 4.15, W = 102.0 mm and h = 1.6 mm we get:

ΔL = 0.7716 mm

Step 10: Calculation of actual length of patch ( L ): The actual length is obtained by re-writing equation

(3.3) as:

L= Leff −2Δ L

Substituting L eff = 95.43 mm and ΔL = 0.7716 mm

we get: L = 0.093 m = 93.00 mm = 2b

Step 11: Calculation of the ground plane dimensions (L g and W g) :

The transmission line model is applicable to infinite ground planes only. However, for practical

considerations, it is essential to have a finite ground plane. It has been shown by that similar results for

finite and infinite ground plane can be obtained if the size of the ground plane is greater than the patch

dimensions by approximately six times the substrate thickness all around the periphery. Hence, for this

design, the ground plane dimensions would be given as:

Lg = 6 h + 2a = 6(1.6) + 114.00mm = 123.6 mm

Wg = 6 h + 2b = 6(1.6) + 93 = 102.6 mm

Step 12: Determination of feed point location (X f, Y f ) :

A coaxial probe type feed is to be used in this design. As shown in Figure 4.1, the center of the patch is

taken as the origin and the feed point location is given by the co-ordinates (X f, Y f ) from the origin. The

feed point must be located at that point on the patch, where the input impedance is 50 ohms for the

resonant frequency. Hence, a trial and error method is used to locate the feed point. For different locations

of the feed point, the return loss (R.L) is compared and that feed point is selected where the R.L is most

negative. According to there exists a point along the length of the patch where the R.L is minimum.

Hence (xf ,yf)=(30mm, 28mm)

b. Radiation Pattern plots

Since a microstrip patch antenna radiates normal to its patch surface, the elevation pattern for φ = 0 and φ

= 90 degrees would be important. Figure 4.2 shows the gain of the antenna at 4 GHz for φ = 0 and φ = 90

degrees.



Figure 4.2 Elevation Pattern for Φ = 0 and Φ = 90 degrees

The maximum gain is obtained in the broadside direction and this is measured to be 6.02 dBi for both, Φ

= 0 and Φ = 90 degrees.

Figure 4.3. Radiation pattern in E-plane and H-plane

The back lobe radiation is sufficiently small and is present due to finite ground plane. The average current

distribution in the feed patch is shown in figure 4.4. Figure 4.4. Current distribution in Microstrip antenna



c. 3-D Radiation Pattern

Figure 4.5. 3-D Radiation Pattern Microstrip antenna

V. Information:

Comparison of different feeding technique

VI. Applications

1. Used in telecommunication industry

2. Used in aircrafts and missiles

3. Designed for multiple frequency



4. Due to its excellent frequency response can be used in various field

VII. Scope in Future

The micro strip antenna finds various applications in various important fields. The fact that micro strip

antenna is used for planar and non-planar surfaces it can be used extensively in almost all kinds of

applications. The major field where the micro strip antenna can be used is aircraft satellites and in

missions of celestial bodies. The micro strip also has ability to be fabricated on a PCB which makes it

distinctly unique and thus allowing the it to be used in micro-applications as well. The micro strip can be

used in high frequency application which also is an added advantage. All these reasons just assert the fact

micro strip antenna is “The” antenna for future applications in this technologically advancing world.

VIII. Conclusion:

The results obtained in this study reveal that the elliptical microstrip antenna is suitable for wireless

communication. In this paper microstrip antenna for wireless communication have been designed using

FR4 substrate.

References:

1. C. A. Balanis, “Antenna Theory, Analysis and Design,” John Wiley & Sons, New York, 1997.

2. Ray K.P. and Kumar Girish,” Broadband Microstrip Antenna,” Artech House, UK, 2003

3. Antennas-John D. Kraus, Tata McGraw Hill publication

4. D. M. Pozar and D. H. Schaubert, Microstrip Antennas: The Analysis and Design of Microstrip

Antennas and Arrays, IEEE Press, 1995.

5. http://en.wikipedia.org/wiki/microstrip_antenna(28/10/2011)

6. http://www.dspguide.com/ch27/6.htm(1/11/2011)



CHEMICAL BATTERY AS SUBSTITUTE TO CONVENTIONAL FUEL Sahil Inamdar, Akshay Tharval, Bhoomika Sheth,

Chemical Department, D. J. Sanghvi College of Engineering, Mumbai 400056


Abstract

In this paper we have discussed the possible means to run a car using chemical engineering and

various chemical reactions. The main purpose of this paper is to solve the world fuel crisis with a

simple household solution. We have highlighted the use of chemical cells for the same by making

use of a working model of a small car.

Our experiments demonstrate the use of lemon batteries as a substitute to the traditional alkaline

batteries. Lemon juice containing citric acid makes up an excellent electrolyte using Copper and

Magnesium as electrodes. The working of a cell is based on simple electrolytic cell which is a

combination of redox reactions. The power drawn by the cell is directly proportional to the

concentration of lemon juice used. A single lemon cell gives enough voltage to power an LED.

During this experiment we found out that the current drawn per cell is very less. Connecting

enough cells in series and parallel combinations draws enough power to run a motor of the car.

Because of the small current being drawn the final battery was very bulky. To overcome this

difficulty we found out various other solutions which can draw more power than lemon juice. They

are

• Bleach cell

• Salt cell

• Vinegar cell

Among the above solutions, bleach cell is the most efficient and long lasting. All the above

mentioned cells including the Lemon cell are eco friendly i.e. there isn’t any waste or toxic gases

evolving. Using chemical cells and improvising them on a larger scale can certainly help reduce the

energy crisis all over the world.

Keywords: Alkaline batteries, concentration, electrolyte, series & parallel combinations.

I. INTRODUCTION

Nothing happens in the world without energy. Civilizations would collapse if it ceased to be

available. Civilizations advance by deploying energy in ever greater abundance. Petroleum is one of

the legacies of the past, being the partially decomposed residue of organic matter, such as plankton

and algae, that sank to the bottom of lakes and seas and was later subjected to heat and pressure. It is,

of course, an extraordinarily convenient source of energy, as it can be transported easily, even in

weight-sensitive aircraft.



Chemical Engineers contribute at all levels and to all aspects of developing both new sources of

energy and more efficient applications of current sources. Chemical Engineers have long contributed

to the refinement of this raw material, which is squeezed and pumped from the ground. They have

developed processes and catalysts that have taken the molecules provided by nature, cut them into

more volatile fragments, and reshaped them so that they burn more efficiently. Of course, burning

nature’s underground bounty might be seen, especially by future generations, as the wanton

destruction of an invaluable resource. The supply of petroleum is also finite and, although new

sources of petroleum are forever being discovered, for the time being at least, they are proving

hazardous and increasingly expensive to access and use. Although an “empty” Earth is decades away,

one day non-renewable resources such as petroleum will be depleted. Chemical Engineers are already

at work on the development of new sources of energy.

Nature, with its head start of four billion years on laboratory, Chemical Engineers have already

developed a highly efficient system based on chlorophyll.

Electrochemistry, the use of chemical reactions to generate electricity and the use of electricity to

bring about chemical change, is potentially of huge importance to the world. Chemical Engineers

have already helped to produce the mobile sources, the batteries that drive our small portable

appliances, such as lamps, music players, laptops, telephones, and monitoring devices of all kinds, as

well as, increasingly, our cars.

Finally, there are various other methods to generate energy such as the solar energy and wind energy.

But the generation of electricity from these sources requires huge plants to be set up which are very

complicated and costly. Also highly skilled labour is required to run and handle such plants. Hence

the use of simple household methods to generate electricity comes in handy.

A novel technique which we practised was with the use of a lemon cell i.e. Lemon juice (citric acid)

as electrolyte in our electrochemical cell. In our method copper and magnesium strips are used as the

two electrodes. In this process redox reaction takes place, which is the main reason for power

generation. In this reaction the anode metal oxidises and electrons flow through the electrolyte to the

cathode thus completing the circuit. By connecting external wires we can work up several electrical

devices.

II. BATTERY DESIGN

Cuvettes are used to hold the lemon juice (100% concentrated). 5 ml of the electrolytic solution was

used. Magnesium and copper strips were dipped inside the juice, taking care that the two electrodes

do not touch each other in the electrolyte. For this purpose clay can be used as it does not react in the

solution and also provides a firm base for the electrodes where they can be mounted on. Connect

wires to the free end of the electrodes.



Fig1. Materials used

Fig2. Sample lemon Battery

III. EXPERIMENT

A potential difference of about 1.7V was measured across the two terminals of the cell by making the

above set up. The motors used in this experiment were standard 9V, 100 rpm motors. To increase the

voltage many such single cells were connected in series combination.

Sr. No. No. of cells in series

connection

Voltage measured

(Volts)

1. 1 1.7

2. 2 3.4

3. 4 7.0

4. 6 10.3

5. 10 15.8

This voltage received was much more than the current obtained. It was observed that the current

measured from a single cell was comparatively low i.e. 0.1 micro Amps. It was noted that the motors



were working on the principle of maximum power dissipated. Power being a product of potential

difference and current (V*I) had to be maximised. To overcome this difficulty we connected single

cells in parallel so that the current value rises up.

Sr. No. No. of cells in parallel

connection

Current measured

(micro Amps)

1. 2 0.15

2. 6 0.4

3. 10 0.79

4. 15 1.1

5. 20 1.4

By keeping cells in parallel the voltage was not affected. The goal was to maximize the performance

of our car. Increasing the number of cells connected in series will increase the voltage supplied by the

battery. Increasing the voltage supplied to a dc electric motor will increase its maximum rotational

speed. Increasing the number of cells connected in parallel will increase the current supplied by the

battery. Increasing the current supplied to a dc electric motor will increase the maximum applied

torque of the motor.

Thus by numerous trial and error methods it was found that 20 cells of such kind when connected in

parallel provided enough power to run a motor. Though enough to run the motor, it was not enough to

run a car. Hence two batches of twenty cells in parallel each were connected in series which helped to

get the required current as well as voltage and in return the power to run the two adjacent motors of

the car. This same procedure was repeated for the other two motors.

IV. HOW IS POWER GENERATED?

The energy for the battery comes from the chemical change in the Magnesium when it dissolves into

the acid. The energy does not come from lemon (electrolyte). Magnesium is oxidized inside the

lemon, exchanging some of its electrons with the acid in order to form hydrogen gas in the electrolytic

solution which evolves from the copper (cathode). The Magnesium (anode) reaches a lower energy

state, and the energy released provides the power. This power generated is enough to light up a LED

for three days.

V. MECHANISM



When the cell is providing an electrical current through an external circuit, the metallic Magnesium at

the surface of the Magnesium electrode is dissolving into the solution. Magnesium atoms dissolve into

the liquid electrolyte as electrically charged ions (Mg2+), leaving 2 negatively charged electrons (e-)

behind in the metal:

Mg → Mg2+ + 2e-

This is an oxidation reaction. While Magnesium is entering the electrolyte, two positively

charged hydrogen ions (H+) from the electrolyte combine with two electrons at the copper electrode's

surface and form an uncharged hydrogen molecule (H2):

2H++ 2e- → H2

This is a reduction reaction. The electrons used from the copper to form the molecules of hydrogen

are made up by an external wire or circuit that connects it to the Magnesium. The hydrogen molecules

formed on the surface of the copper by the reduction reaction ultimately bubble away as hydrogen

gas.

VI. PROBLEMS FACED

Fig 3. A single cell in reaction phase

As seen in the above figure the hydrogen gas evolved was towering the cuvettes in its reaction phase.

Hydrogen gas being combustible was seen as a hazard and had to be taken care of. Changing the ion

concentration was one of the ideas. This could have been done by:

• Changing electrolyte concentration

• Changing ion concentration

The electrolyte concentration was changed to 10%, 25%, 50% & 75% and then readings were taken

for voltage. The following data was noted.



Sr. no. Concentration (%) Voltage (V)

1. 10 0.2

2. 25 0.5

3. 50 0.8

4. 75 1.2

5. 100 1.7

Thus it was concluded to use 100% concentration of lemon juice.

It was then decided to add salt to the electrolyte to check whether the ion concentration changes. It

was observed that the addition of salt actually decreased the voltage from 1.7V to 1.53V making it

unsuitable to use.

VII. CONCLUSION

It was seen that the batteries had enough power to run the motor but at a very slow speed. The motors

when connected to the wheels weren’t able to withstand the weight of the car for too long and would

abruptly stop. It was observed that after a certain span of time the potential difference between the

two electrodes dropped. When the weight of the car was reduced, the car covered a greater distance

than the previous case but stopped after sometime because of the weight again and also the

magnesium electrode started to dissolve in the electrolyte and the copper strip changed colour. The

major problem that occurred during the experiment was that these lemon cells were like “one time

use” or use and throw kind of batteries. They cannot be reused or recycled. The container had to be

emptied and then refilled again after sometime as the efficiency of the battery decreased, this was

because the lemon juice was not a very strong electrolyte and would dissociate fast.

To overcome these difficulties we found an efficient option i.e. using bleach cell.

Bleach cell

The main aim for us to study about bleach cell was to get a very efficient substitute to lemon juice.

Substituting the lemon juice in the cuvettes by pure bleach one can overcome the above mentioned

difficulties. Make the use of the same electrodes i.e. copper and magnesium taking care that the two

electrodes do not touch. An unloaded bleach cell records a potential difference of 1.87V across the

two terminals while the current was 0.1 micro Amps. Suitable resistances ranging from 100 to 10k

ohms can be used in the circuit. This will help to increase the current compromising the voltage which

is of greater efficiency. One such cell connected to a 2.5k ohms resistor records a potential difference

of 0.606V while the current shoots up to 0.25 mA. Connecting such cells in suitable series and

parallel combinations helps increase the current and voltage and in return the power, helping the

motor to run better. Though bleach cells took a little time to start up but once started it would give a



constant which lasted for a very long time. A single unloaded bleach cell can easily light up a LED for

a week’s time.

VIII. FUTURE PROSPECTS AND ADVANCEMENTS

The major advantage of a chemical battery is that there are no hazardous pollutants given out in the

environment. Though the project carried out by us was on a small scale and to power a small car this

idea can be implemented on a greater scale by improvising techniques used. Not only for cars or

automobiles such technique can be used but also to power any small or large electronic gadget by

improvising it. This can be done by increasing the number of cells used in series and parallel

combination. This reduces the use of conventional sources of energy such as petroleum with simple

material which can we can get in abundance cutting down the cost to a great extent.

Fig 4. Cuvettes holding the electrolyte

Fig 5. Arrangement of cells in the car



Fig 6. Sample car

REFERENCES

1. Sorey, Timothy; Hunt, Vanessa; Balandova, Evguenia; Palmquist, Bruce (2012). "Juan's Dilemma:

A New Twist on the Old Lemon Battery". In Metz, Steve. Fuel for Thought: Building Energy

Awareness

2. General Chemistry Darrell D. Ebbing, Steven D. Gammon – 2009

3. Lemon Battery Jesse Russell, Ronald Cohn - 2012



DEVELOPMENT OF A DEVICE TO MEASURE THE BLADE TIP CLEARANCE OF AN AXIAL COMPRESSOR

Dr. S.M.Khot*#1, Dr.A.M.Pradeep*&2, Sagar Chavan#3, Manasi Ghogare#4, Srushti Koli#5 *Guides, #Mechanical Department, Fr.C.Rodrigues Insitute of Technology,

Vashi, Navi Mumbai, India. &Aerospace Department, Indian Institute of Technology, Bombay, India.

[email protected], [email protected], [email protected], [email protected] [email protected]

Abstract

Axial compressors, used in gas turbines, jet engines and also small scale power plants, are rotating,

airfoil based compressors in which the working fluid flows parallel to the axis of rotation. There has

been continuous struggle to maximize the efficiency of these compressors. One of the many ways to

achieve the same is to minimize the tip clearance i.e. to reduce the distance between the blade tip and

the housing. Experiments need to be conducted to measure the changes in the tip clearance while the

compressor is operating. Conventional devices to measure this tip clearance have proven to be costly if

a small scale application is under consideration. Our aim in this project is to develop a device which

will measure the blade tip clearance of an axial flow compressor economically. The literature review,

development of the device, its working and results will be discussed in this paper.

Keywords- Tip Clearance Measurement, Eddy Current Probe, Data Storage Oscilloscope, Eddy Current

Technique

I. INTRODUCTION

Minimizing the tip clearance reduces the amount of fuel burned, it lowers the rotor inlet temperature; thus

improving turbine efficiency. The reduction of emissions results in extended service life of the

compressor and also enhances the mission range capabilities in jet engines. The various methods available

to measure this tip clearance include:

A. Optical Fourier Domain Reflectrometry (OFDR)

OFDR is a method used to measure back reflections from optical fiber networks and components. The

signals reflected from the device under test interfere with the reflections from a fixed surface; OFDR

detects these interfering signals and generates a Fourier transform of the same, thus allowing visualization

of multiple reflections [1] of the same, thus allowing visualization of multiple reflections[1].

B. Laser Doppler Velocimetry (LDV)



In an LDV, two coherent laser beams are brought to an intersection under a small angle, such that inside

the volume of intersection an interference fringe system with nearly parallel fringes of uniform spacing is

generated [3]. An object passing perpendicularly through this measurement volume (i.e., here the turbine

blade tip) scatters light that is amplitude modulated with the Doppler difference frequency. A wavelength

sensitive detection of this frequency results in axial position of the moving object.

C. Capacitive Sensor Method

The capacitive sensor method works on the principle of capacitance. The main components of the

capacitive proximity sensor are plate, oscillator, threshold detector and the output circuit.

The plate inside the sensor acts as one plate of the capacitor and the target as another plate and the air as

the dielectric between the plates [2]. As the object comes close to the plate of the capacitor, the capacitance

increases and as the object moves away the capacitance decreases. The capacitive sensor can detect any

targets whose dielectric constant is more than that of air.

Though the above methods are widely used, they have their respective disadvantages which are stated

below:

• The optical methods i.e. OFDR and LDV are sensitive to contamination and are not suitable for

compressors subjected to heavy vibrations.

• Capacitive sensors are affected by humidity and temperature variation; they are also difficult to

design for practical applications.

• Optical devices are costlier than other devices available to serve this purpose and they are also very

delicate and need extra care while in use.

II. EDDY CURRENT TRANSDUCERS

The process of Electromagnetic Induction is responsible for the production of eddy currents. In this

process an alternating current when applied to a conductor, such as copper wire, develops a magnetic field

in and around the conductor. When this alternating current rises to maximum, the magnetic field expands

and vice versa. Now, if a second conductor is brought in close proximity of this changing magnetic field,

the current will be induced in the second conductor. Eddy currents are these induced currents which flow

in a circular path.

An eddy current transducer uses the principle of Electromagnetic Induction and generates eddy currents

which can be used to detect the distance between the two conductors. The only constraint with this

method is that the second conductor is to be metallic in order to generate eddies i.e. the blade of the

turbine should be a metal, if in case a ceramic or plastic blade is used for a small scale application they

can be given a metallic coating to make the blades suitable for this application.



A typical circuit which can be used to generate eddies and to measure the tip clearance is shown in Fig.1.

Fig.1 Eddy Current Transducer [5]

In the above figure, the probe is used to generate the eddy currents. It consists of an active and a

compensating coil. The magnetic flux is induced in the active coil and is passed through the conducting

material (second conductor) to produce eddy currents. The compensating coil is given to provide

temperature compensation; hence it is on the adjacent arm of the bridge circuit. The eddy current is

detected with the help of an analog meter through which the output can be visually seen.

A. Advantages:

• Sensitive to small distance variation.

• Equipment is portable.

• Minimum part preparation is required.

• Economical method.

• Can work in arduous environmental condition.

B. Disadvantages:

• Only conductive elements can be inspected, but non-conducting elements can be given a metallic

coating.

• Range of the eddy probe is limited to 4 to 5 mm, but the tip clearance ranges between 3 to 4mm.

III. DEVELOPMENT OF THE TIP CLEARANCE MEASURING DEVICE

The components required to successfully implement the circuit and to conduct the testing are:



A. Eddy Current Probe:

In order to generate the eddy current, eddy probes are used. There are many such probes available for a

variety of applications but choosing the appropriate probe to suit the application is important. The types

of probes available are:

• Differential Probes:

These probes have two active coils wound in opposition and are used to detect surface defects[8]. When

both the active coils are over a smooth surface they do not show any differential signal, however if one

of the active coils is over a defect then a differential signal is produced. Hence these probes are used

for flaw detection.

• Reflection Probes:

These probes have two coils similar to differential probes but one coil is used to excite the eddy

currents while other is used to sense the changes in the testing material [8]. These probes are the most

advantageous as both the coils can be optimized for the desired purpose.

• Absolute Probes:

These are simplest type of probes; they incorporate the basis of eddy current generation and have as

active coil which produces the eddy current and a compensating coil[8]. Such probes are widely used

because of their wide range of applications.

Though the reflection probes are more accurate and can be optimized according to the application, they

are costly. After comparing the reflection and absolute probes, it is found that the absolute probes are apt

for this particular application.

Fig. 2 Eddy Current Pencil Probe

Figure 2 shows the surface type pencil probe. The diameter of this probe is 5mm and its length is 4cm.

Since the testing range of these probes is 4 to 5 mm they ensure accuracy in measurement.

B. Resistance:



The resistance shown in Fig. 3 is to be chosen depending upon the peak to peak voltage (which is 1 to 2

Volts) as specified by the manufacturer of the eddy probe. This resistance is finalized by trying out

various set of standard resistance values and a value of 1k ohms is chosen.

Fig 3 Resistance(1000Ω)

C. Function generator and Two channel Data Storage Oscilloscope:

A function generator acts as an input device, wherein the values of frequency and input voltage can be set

for the circuit. The value of limiting frequency is specified by the manufacturer of the probe and is 50 to

500 kHz. An input of 59 kHz is thus given to the circuit. A Two Channel Data Storage Oscilloscope

(DSO), as shown in the Fig. 4, acts as an output device and also gives the waveforms related to the input

as well as output values. Since the obtained readings from the DSO can be stored, accuracy is ensured.

Fig. 4 Two Channel Data Storage Oscilloscope.

IV. PRECAUTIONS

The following precautions are taken into consideration before testing the probe:

• Meeting the specified voltage/current constraints of each component used, failure of which may result

in severe damage to those expensive components.

• Working out the circuit on paper, making sure it is a closed circuit, before attempting it on the bread

board.

V. EXPERIMENTAL SETUP

Initially the testing of the probe is done with a metal plate and the entire setup is as shown in Fig. 5.



Fig. 5 Circuit Used to Test the Probe.

Two wires of input from the function generator are taken, one of which goes to the bread board and the

other goes to the DSO. Output from the breadboard goes to the DSO and hence we get the input-output

waveforms. The metal plate is kept at varying distances from the probe tip and the corresponding change

in the voltage is noted. The metal plate kept with respect to the probe is shown in Fig. 6.

Fig .6 Positioning of the Probe with Respect to the Conducting Plate.

Waveforms of each of the readings were obtained with the help of the DSO as shown in Fig.7:

Fig.7 Waveform generated at different distances



Since the output voltage is in millivolts, there is a need for an amplification circuit.

For amplification, the value of resistance is decreased to 470 Ohms and in order to get precise readings

the distance between the metal place and the probe tip is varied in steps of 0.2mm using a micrometer and

the corresponding voltage values are tabulated below in Table 1.

Table. I

Variation of voltage readings with deflection of conductor plate from probe tip.

Distance Voltage (mV)

0 110

0.2 100

0.4 98

0.6 94

0.8 96

1 94

1.2 92

1.4 92

1.6 90

1.8 90

2 89

A graph was plotted with the help of the readings obtained, in order to get an overall idea about how the

voltage varies with respect to the change in distance. The graph obtained is as shown in Fig. 8.

Fig.8 Calibrating graph giving relation between the distance and voltage

y = ‐8.045x + 103.0R² = 0.778

0

40

80

120

0 1 2 3

Vol

tage

(mV

)

Distance(mm)

Tip Clearance Measurement

Volts

Linear (Volts)



As observed, the voltage varies inversely with the distance between the metal conductor and the probe tip

given by the Eq. 1 .

Thus, for a given value of voltage (y), we can calculate the distance (x) using the above

equation thus giving us the value of the tip clearance in this case.

The above values obtained are checked for accuracy and hence the percentage error is calculated. The

following table shows the calculated error.

Table. II: Error calculation

According to the values obtained it is seen that the average error is 13.11%, since the value is below 20%

it can be said that the error is within acceptable limits.

VI. RESULTS

• The Eddy probe is tested successfully and the readings as obtained are tabulated as shown in Table 1.

• The readings show that if the distance between the probe and the conducting plate is varied then the

voltage changes along with it with an inverse proportion.

Actual Distance Voltage (mV) Distance

obtained

Error

0 110 0

0.2 100 0.37 46.73%

0.4 98 0.62 35.72%

0.6 94 1.11 46.73%

0.8 96 0.87 8%

1 94 1.11 9.91%

1.2 92 1.36 12.30%

1.4 92 1.36 -2.90%

1.6 90 1.616 0.90%

1.8 90 1.616 -11.38%

2 89 1.74 -14.93%

y = -8.045x + 103.0 (1)



VII. CONCLUSION

The entire experiment proves that the Eddy current Transducer method is apt to measure the tip clearance

change and the entire setup can be mounted on a test rig to measure the same.

ACKNOWLEDGEMENT

We are sincerely thankful to our H.O.D, 'Dr. S. M. Khot' and our principal 'Dr. Rollin Fernandes' for

giving us an opportunity to work on this project.

Also we would like to thank our external project guide Associate Professor 'A. M. Pradeep' of the

Aerospace Department, IIT Bombay and our internal project guide 'Dr. S. M. Khot' for their valuable

guidance and assistance throughout the course of this project. We are also thankful to Mr. Arvind from

the electrical department of Fr.C.R.I.T for his immense co-operation and Prof. S. S. Thale for his

guidance.

REFERENCES

[1]. Andrei B. Vakhtin1, Shin-Juh Chen2, and Steve M. Massick3 , ”Optical Probe for Monitoring Blade

Tip Clearance.” In conference at 47th AIAA Aerospace Sciences Meeting Including The New

Horizons Forum and Aerospace Exposition 5 - 8 January 2009, Orlando, Florida.

[2]. A.G.Sheard , “Blade by Blade Tip Clearance Measurement.”, Hindawi Publishing Corporation

International Journal of Rotating Machinery Volume 2011, Article ID 516128, 13 pages

doi:10.1155/2011/516128

[3]. Lars Büttner, Thorsten Pfister, and Jürgen Czarske. , “Fiber-optic laser Doppler turbine tip

clearance probe.” in international journal of OPTICS LETTERS,May 1, 2006 ,Vol. 31, No. 9.

[4]. S Z Cao, F J Duan and Y G Zhang “Measurement of Rotating Blade Tip Clearance with Fibre-Optic

Probe.” Journal of Physics: Conference Series 48 (2006) 873–877

[5]. Web Link: http://www.InstruementationToday.com.

[6]. Web Link: http://www.wikipedia.com.

[7]. Web Link:http://www.chenyang-ism.com.

[8]. Web Link: http://www.ndt-ed.org.



GRAPHENE: THE ADVANCED MATERIAL

Asim Kulkarni Indira College of Engineering and Management, Pune, India

[email protected]

Abstract

Graphene is a rapidly rising star on the horizon of materials science and nanotechnology. This strictly

two-dimensional material exhibits exceptionally high crystal and electronic quality, and, despite its

short history, has already revealed a new dimension of physics and potential applications, which are

briefly discussed here. Whereas one can be certain of the realness of applications only when

commercial products appear, graphene no longer requires any further proof of its importance in terms

of fundamental physics. More generally, graphene represents a conceptually new class of materials

that are only one atom thick, and, on this basis, offers new inroads into low-dimensional physics that

has never ceased to surprise and continues to provide a fertile ground for applications.

Keywords - External quantum efficiency, Buckyballs, Van Der Waals forces.

I. INTRODUCTION

Graphene is a single atomic layer of carbon atoms tightly packed in a two-dimensional honeycomb lattice

microscopy. The first graphene was extracted from graphite using a technique called micromechanical

cleavage. This approach allowed easy production of high-quality graphene crystallites and further led to

enormous experimental activities. . Graphene has a high electron (or hole) mobility as well as low

Johnson noise (electronic noise generated by the thermal agitation of the charge carriers inside an

electrical conductor at equilibrium, which happens regardless of any applied voltage) Combination of

excellent electrical property and low noise make graphene an ideal material in the electronics. 2D

materials display very interesting properties, and are fundamentally different from the 3D materials we

encounter everyday. The discovery of 2D materials means that scientists now have access to materials of

all dimensionalities, including 0D (quantum dots, atoms) and 1D (nanowires, carbon nanotubes)

II. STRUCTURE

Graphene is a member of the class of 2-dimensional materials. It consists of a hexagonal array of sp2-

bonded carbon atoms, just like those found in bulk graphite.



.

s px+py sp2 pz

Fig. 1: Atomic structure of Graphene in the form of quantum numbers.

III. SYNTHESIS

A. Exfoliation and Cleavage

Graphite is stacked layers of many graphene sheets, bonded together by weak Van Der Waals force. Thus,

in principle, it is possible to produce graphene from a high purity graphite sheet, if these bonds can be

broken. Exfoliation and cleavage use mechanical or chemical energy to break these week bonds and

separate out individual graphene sheets.

Fig. 2: Separation of Graphene sheets

B. Thermal Chemical Vapor Deposition Techniques

In this work, a natural, eco-friendly, low cost precursor, camphor, was used to synthesize graphene on Ni

foils. Camphor was first evaporated at 180°C and then pyrolyzed, in another chamber of the CVD

furnace, at 700 to 850°C, using argon as the carrier gas. Upon natural cooling to room temperature, few-

layer graphene sheets were observed on the Ni foils.

Fig. 3: Vapors containing Graphene being deposited.



C. Plasma Enhanced Chemical Vapor Deposition Techniques

Interest in synthesizing graphene through plasma enhanced chemical vapor deposition (PECVD) is

contemporary to that of exfoliation. The earliest report had proposed a DC discharge PECVD method to

produce so called nanostructured graphite-like carbon (NG). Simplicity of the process immediately

attracted attention of the scientific community and the same kind of process was followed by many

research groups, worldwide.

Fig. 4: Graphene deposited on Plasma.

PECVD method has shown the versatility of synthesizing graphene on any substrate, thus expanding its

field of applications. Future developments of this method should bring out better control over the

thickness of the graphene layers and large scale production.

IV. PROPERITES

Graphene has several good properties. It conducts heat readily, so it can be easily cooled. It can withstand

temperatures of several thousand degrees. Graphene doesn't melt easily. It is, however quite flammable. If

there is any oxygen, it will burn up. In addition to its exceptional electrical conductivity, graphene is the

strongest known substance. By creating holes within a sheet of graphene, then “doping” those holes with

desired impurities, semiconductors can be made that are nearly unbreakable and highly flexible. As a

bonus, graphene is a superb heat conducting material, so heat would not be the problem it is with current

semiconductor materials. Yet, optimism must remain guarded until tangible results have been produced.

This novel material is atomically thin, chemically inert, consists of light atoms, and possesses a highly

ordered structure. Graphene is electrically and thermally conductive, and is the strongest material ever

measured. These remarkable properties make graphene the ideal material. One photon can be converted

into multiple electrons.

A paradigm shift in the materials industry is likely within the near-future as a variety of unique materials

replaces those that we commonly use today, such as plastics. Among these new materials, graphene

stands out. The single-atom-thick sheet of pure carbon has an enormous number of potential applications



across a variety of fields. Its potential use in high-efficiency, flexible, and transparent solar cells is among

the potential applications.

A new discovery by researchers has revealed that graphene is even more efficient at converting light into

electricity than previously known. Graphene is capable of converting a single photon of light into

multiple electrons able to drive electric current. The discovery is an important one for next-generation

solar cells, as well as other light-detecting and light-harvesting technologies. In most materials, one

absorbed photon generates one electron, but in the case of graphene, it is seen that one absorbed photon is

able to produce many excited electrons, and therefore generate larger electrical signals. It was known that

graphene is able to absorb a very large spectrum of light colors. However now it is known that once the

material has absorbed light, the energy conversion efficiency is very high. Our next challenge will be to

find ways of extracting the electrical current and enhance the absorption of graphene. Then we will be

able to design graphene devices that detect light more efficiently and could potentially even lead to more

efficient solar cells

.

Fig. 5: Graphene as substrate in Solar cell.

V. APPLICATIONS AND USES

A. Electrodes with very high surface area.

Researchers have developed electrodes made from carbon nanotubes grown on graphene. The researchers

first grow graphene on a metal substrate then grow carbon nanotubes on the graphene sheet. Because the

base of each nanotube is bonded, atom to atom, to the graphene sheet the nanotube-graphene structure is

essentially one molecule with a huge surface area.

B. Lower cost solar cells:

Researchers have built a solar cell that uses graphene as a electrode while using buckyballs and carbon

nanotubes to absorb light and generate electrons; making a solar cell composed only of carbon. The



intention is to eliminate the need for higher cost materials, and complicated manufacturing techniques

needed for conventional solar cells

C. Transistors that operate at higher frequency.

The ability to build high frequency transistors with graphene is possible because of the higher speed at

which electrons in graphene move compared to electrons in silicon. Researchers are also developing

lithography techniques that can be used to fabricate integrated circuits based on graphene.

D. Lower cost of display screens in mobile devices.

Researchers have found that graphene can replace indium-based electrodes in organic light emitting

diodes (OLED). These diodes are used in electronic device display screens which require low power

consumption. The use of graphene instead of indium not only reduces the cost but eliminates the use of

metals in the OLED, which may make devices easier to recycle.

E. Storing hydrogen for fuel cell powered cars.

Researchers have prepared graphene layers to increase the binding energy of hydrogen to the graphene

surface in a fuel tank, resulting in a higher amount of hydrogen storage and therefore a lighter weight fuel

tank. This could help in the development of practical hydrogen fueled cars.

F. Sensors to diagnose diseases.

These sensors are based upon graphene's large surface area and the fact that molecules that are sensitive to

particular diseases can attach to the carbon atoms in graphene. For example, researchers have found that

graphene, strands of DNA, and fluorescent molecules can be combined to diagnose diseases. A sensor is

formed by attaching fluorescent molecules to single strand DNA and then attaching the DNA to graphene.

When an identical single strand DNA combines with the strand on the graphene a double strand DNA if

formed that floats off from the graphene, increasing the fluorescence level. This method results in a

sensor that can detect the same DNA for a particular disease in a sample.

VI. DRAWBACKS

Graphene’s "external quantum efficiency" is low – it absorbs less than 3% of the light falling on it.

Furthermore, useful electrical current can only be extracted from graphene-based devices that have

electrical contacts with an optimized "asymmetry" – something that has proven difficult to achieve.

Graphene-related materials existed only as conductors or insulators, never as semi-conductors. Graphene

has a low energy band gap, so graphene continues to conduct a lot of electrons even in it’s off state. If

there were billions of graphene transistors on a chip, a large amount of energy would be wasted



VII. CONCLUSION

Although graphene has shown exceptional electrical, optoelectric, and chemical properties and thus, has

excellent potential be used as transparent electrode, field effect transistor, sensors and energy

applications, synthesis of graphene films on arbitrary substrates, with desired energy band gap, still

remained to be achieved. It is expected that after complete development of graphene films, on a large

scale, with desired electrical properties, graphene may become more attractive and thus provide future

electric devices.

REFERENCES

[1] Mechanical and Electrical Properties of Graphene Sheets by Joseph Scott Bunch.

[2] National Science Foundation: Graphene (Images).

[3] BBC News Article: Is graphene a miracle material?

[4] Synthesis of Graphene and Its Applications: A Review by Indranil Lahiri, Raghunandan Seelaboyina,

and Yong Soo Kang.

[5] http://engineering.ucsb.edu.

[6] http://www.futurity.org/.



NON CONVENTIONAL ENERGY SOURCES: SOLAR POND Tejas Gawade, Varun Shinde, Ketan Gawade

Department of MechanicalEngineering K.G.C.E , Karjat, Navi Mumbai, India


Abstract

The sun is the largest source of renewable energy and this energy is abundantly available in all

parts of the earth. It is in fact one of the best alternatives to the non-renewable sources of energy.

One way to tap solar energy is through the use of solar ponds. Solar ponds are large-scale energy

collectors with integral heat storage for supplying thermal energy. It can be use for various

applications, such as process heating, water desalination, refrigeration, drying and power

generation. The solar pond works on a very simple principle. It is well-known that water or air is

heated they become lighter and rise upward e.g. a hot air balloon. Similarly, in an ordinary pond,

the sun’s rays heat the water and the heated water from within the pond rises and reaches the top

but loses the heat into the atmosphere. The net result is that the pond water remains at the

atmospheric temperature. The solar pond restricts this tendency by dissolving salt in the bottom

layer of the pond making it too heavy to rise. Though solar ponds can be constructed anywhere, it

is economical to construct them at places where there is low cost salt and bittern, good supply of sea

water or water for filling and flushing, high solar radiation, and availability of land at low cost.

Keywords- Solar thermal energy, Convecting Solar Ponds, Nonconvecting Solar Ponds, Salinity

gradient, Desalination

I. INTRODUCTION

A solar pond is simply a pool of saltwater which collects and stores solar thermal energy. The

saltwater naturally forms a vertical salinity gradient also known as a "halocline", in which low-salinity

water floats on top of high-salinity water. The layers of salt solutions increase in concentration (and

therefore density) with depth. Below a certain depth, the solution has a uniformly high salt

concentration. There are 3 distinct layers of water in the pond:

• The top layer, which has a low salt content.

• An intermediate insulating layer with a salt gradient, which establishes a density gradient that

prevents heat exchange by natural convection.

• The bottom layer, which has a high salt content.



If the water is relatively translucent, and the pond's bottom has high optical absorption, then nearly all

of the incident solar radiation (sunlight) will go into heating the bottom layer.

When solar energy is absorbed in the water, its temperature increases causing thermal expansion and

reduced density. If the water were fresh, the low-density warm water would float to the surface,

causing convection current. The temperature gradient alone causes a density gradient

that decreases with depth. However the salinity gradient forms a density gradient that increases with

depth, and this counteracts the temperature gradient, thus preventing heat in the lower layers from

moving upwards by convection and leaving the pond. This means that the temperature at the bottom

of the pond will rise to over 90°C while the temperature at the top of the pond is usually around 30

°C. A natural example of these effects in a saline water body is Solar Lake in the Sinai

Peninsula of Egypt.

The heat trapped in the salty bottom layer can be used for many different purposes, such as the

heating of buildings or industrial hot water or to drive an organic Rankine cycle turbine or Stirling

engine for generating electricity.

II. TYPES OF SOLAR PONDS

There are two main categories of solar ponds:

• nonconvecting ponds, which reduce heat loss by preventing convection from occurring within

the pond; and

• convecting ponds, which reduce heat loss by hindering evaporation with a cover over the

surface of the pond.

A. Convectıng Solar Ponds:

A well-researched example of a convecting pond is the shallow solar pond. This pond consists of pure

water enclosed in a large bag that allows convection but hinders evaporation. The bag has a blackened

bottom, has foam insulation below, and two types of glazing (sheets of plastic or glass) on top. The

sun heats the water in the bag during the day. At night the hot water is pumped into a large heat

storage tank to minimize heat loss. Excessive heat loss when pumping the hot water to the storage

tank has limited the development of shallow solar ponds.

Another type of convecting pond is the deep, saltless pond. This convecting pond differs from shallow

solar ponds only in that the water need not be pumped in and out of storage. Double-glazing covers

deep saltless ponds. At night, or when solar energy is not available, placing insulation on top of the

glazing reduces heat loss.

B. Nonconvectıng Solar Ponds:

There are two main types of nonconvecting ponds: salt gradient ponds and membrane ponds. A salt

gradient pond has three distinct layers of brine (a mixture of salt and water) of varying concentrations.



Because the density of the brine increases with salt concentration, the most concentrated layer forms

at the bottom. The least concentrated layer is at the surface. The salts commonly used are sodium

chloride and magnesium chloride. A dark-colored material usually butyl rubber lines the pond. The

dark lining enhances absorption of the sun's radiation and prevents the salt from contaminating the

surrounding soil and groundwater. As sunlight enters the pond, the water and the lining absorb the

solar radiation. As a result, the water near the bottom of the pond becomes warm up to 93.3°C.

Although all of the layers store some heat, the bottom layer stores the most. Even when it becomes

warm, the bottom layer remains denser than the upper layers, thus inhibiting convection. Pumping the

brine through an external heat exchanger or an evaporator removes the heat from this bottom layer.

Another method of heat removal is to extract heat with a heat transfer fluid as it is pumped through a

heat exchanger placed on the bottom of the pond.

Another type of nonconvecting pond, the membrane pond, inhibits convection by physically

separating the layers with thin transparent membranes. As with salt gradient ponds, heat is removed

from the bottom layer. In figure 2 you can see an example of salt gradient solar pond.

Fig. 1 Salt Gradient Solar Pond.

III. ADVANTAGES AND DISADVANTAGES

• The approach is particularly attractive for rural areas in developing countries. Very large area

collectors can be set up for just the cost of the clay or plastic pond liner.

• The evaporated surface water needs to be constantly replenished.

• The accumulating salt crystals have to be removed and can be both a valuable by-product and

a maintenance expense.

• No need of a separate collector for this thermal storage system.

IV. APPLICATIONS

• Salt production (for enhanced evaporation or purification of salt, that is production of

‘vacuum quality’ salt)



• Aquaculture, using saline or fresh water (to grow, for example, fish or brine shrimp)

• Dairy industry (for example, to preheat feed water to boilers)

• Fruit and vegetable canning industry

• Fruit and vegetable drying (for example, vine fruit drying)

• Grain industry (for grain drying) Water supply (for desalination)

• Process heat

Studies have indicated that there is excellent scope for process heat applications (i.e. water heated

to 80 to 90° C.), when a large quantity of hot water is required, such as textile processing and dairy

industries. Hot air for industrial uses such as drying agricultural produce, timber, fish and chemicals

and space heating are other possible applications.

• Desalination

Drinking water is a chronic problem for many villages in India. In remote coastal villages where

seawater is available, solar ponds can provide a cost-effective solution to the potable drinking water

problem. Desalination costs in these places work out to be 7.5paise per litre, which compares

favourably with the current costs incurred in the reverse osmosis or electrodialysis/desalination

process.

• Refrigeration

Refrigeration applications have a tremendous scope in a tropical country like India. Perishable

products like agricultural produce and life saving drugs like vaccines can be preserved for long

stretches of time in cold storage using solar pond technology in conjunction with ammonia based

absorption refrigeration system.

V. EXAMPLES OF SOLAR PONDS

• Bhuj Solar Pond

• El paso Solar Pond

• Pyramid Hill Solar Pond

A. Bhuj Solar Pond

The 6000-square-metre solar pond in Bhuj, the first large-scale pond in industrial environment to cater

to actual user demand, supplied totally about 15 million litres of hot water to the dairy at an average

temperature of 75°C between September 1993 and April 1995. In figure 3 you can see the Bhuj solar

pond.

Fig. 2 The Bhuj Solar Pond.



It was the first experiment in India, which successfully demonstrated the use of a solar pond to supply

heat to an actual industrial user. But, sadly, the Bhuj solar pond, constructed by the Tata Energy

Research Institute (TERI), today lies in disuse for want of financial support and government policy to

help this eco-friendly technology grow.

The Bhuj solar pond was conceived as a research and development project of TERI, which took over

nine years to establish, to demonstrate the feasibility of using a salt gradient pond for industrial

heating.

The solar pond is 100 m long and 60 m wide and has a depth of 3.5 m. The pond was then filled with

water and 4000 tonnes of common salt was dissolved in it to make dense brine.

B. El Paso Solar Pond:

The El Paso Solar Pond project is a research, development, and demonstration project initiated by the

University of Texas at El Paso in 1983. It has operated since May 1986 and has successfully shown

that process heat, electricity, and fresh water can be produced in the southwestern United States using

solar pond technology.

Fig. 4 El Paso Solar Pond.

The El Paso Solar Pond project began when the University of Texas at El Paso discovered an existing

pond which has a 3350 square meter area and 3 meter depth located at Bruce Foods, a canning plant

in northeast El Paso, Texas. In figure 5 you can see another view of El Paso Solar Pond.

Fig. 5 Closer View of El Paso Solar Pond.



Over 90 graduate and undergraduate students have been involved in the project, performing tasks

ranging from construction to applied research. In addition, numerous students have done projects

related to the pond, gaining valuable experience in equipment design and construction, lab techniques,

problem solving, instrumentation, and documentation.

The solar pond provides a unique opportunity to do research in such areas as double diffusive

convection, wind/wave interaction, flow in stratified fluids, and computer modeling. In addition, the

state of the art equipment on site provides an excellent opportunity for energy efficiency studies, cost

analysis, system studies, heat exchanger.

C. Pyramid Hill Solar Pond:

A consortium of RMIT University, Geo-Eng Australia Pty Ltd and Pyramid Salt Pty Ltd has

completed a project using a 3000 square metre solar pond located at the Pyramid Hill salt works in

northern Victoria to capture and store solar energy using pond water which can reach up to 80°C. In

Figure 6 you can see the picture of this solar pond.

Fig. 6 The Pyramid Hill Solar Pond.

Pyramid Salt will use the pond's heat not only in its commercial salt production but also for

aquaculture, specifically producing brine shrimps for stock feed. It is planned in a subsequent stage of

the project to generate electricity using the heat stored in the solar pond, thus making this local

industry more energy self-sufficient.

At the local level this will be a significant boost in an area with high unemployment and a depressed

economy.

VI. COST OF SOLAR PONDS

As technology develops, the energy needs of communities increases. This energy need is provided

from different energy sources known as traditional energy sources, such as coal, fuel oils, geothermal

energy, hydraulic energy, and nuclear energy. These energy sources have some disadvantages. The

first three of these energy sources have limited life times. Hydraulic energy is an insufficient energy

source, and nuclear energy has some unsolved environmental and safety problems. Therefore, the

researchers have condensed their studies on new alternative energy sources known as renewable

energy sources.



These are biomass, biogas, wind energy, wave energy, hydrogen energy, and solar energy.

Solar energy among these energy sources is the most abundant and considerable research is being

carried out in this area. In figure 7 you can see a table which is comparing initial costs of different

water heating systems.

Fig. 7 The Initial Costs of Several Water Heating Systems (1991 prices).

Salinity gradient solar ponds, although not dramatically cheaper than other disposal methods, may still

be a viable option especially in circumstances where the unit cost of power is very high or where

access to a power grid is limited. Moreover, the actual cost of utilizing SGSPs may be lower than

reported when other factors are taken into account, such as savings incurred by bypassing the waste

disposal permitting process, the environmental savings associated with using a renewable fuel, or tax

breaks that may be developed for facilities that use renewable fuels.

REFERENCES:

1. http://edugreen.teri.res.in/explore/renew/pond.htm

2. http://edugreen.teri.res.in/explore/renew/solar.html

3. http://www.eere.energy.gov/consumerinfo/factsheets/aa8.html

4. http://en.wikipedia.org/wiki/Solar_pond



VIBRATION ANALYSIS OF DRILLING OPERATION Amit S. Wani1, Gayatri S. Sagavkar2, Vaibhav K. Bhate3

Department of Mechanical Engineering, Fr.Conceiceo Rodrigues Institute of Technology, Vashi, Navi Mumbai, Maharastra, India


Abstract

Vibrations are produced during any machining process. For drilling operation, analysis of these

vibrations plays an important role in order to predict phenomenon of ‘chatter’. This paper

emphasizes the analysis of vibration during drilling operation. The output results of analysis are

useful to find out amplitude of vibrations produced with respect to drill size and spindle speed for

standard rate of recommended feed/min.

Analysis is quantified and tabulated as per available machining parameters of ‘THAKUR

PELTER DRILLING MACHINE’ which is present in the Workshop of Fr. Conceiceo Rodrigues

Institute of Technology, Vashi, Navi Mumbai. The optimum values of spindle speed and feed for

maximium amplitude of transverse vibrations with respect to drill size are highlighted in the table

and brought to the notice of Workshop Superintendent. The table of formulated results is displayed

near this drilling machine.

Keywords- Chatter, drilling operation

I. INTRODUCTION

Drilling Process is widely used in various types of industries. During drilling many a times, a

phenomenon of ‘chatter’ of drill bit is observed. The reason for this ‘chatter’ is the vibrations

produced during the drilling operation. The vibrations if produced by external parameters can be

controlled by the methods of vibration isolation and carrying out periodic preventive maintenance of

the machine. But, vibrations produced because of drilling itself i.e. due to spindle speed and feed

cannot be controlled completely.

So, such internal vibrations need to be avoided. As these vibrations depend upon the various

machining parameters, calculation of vibrations can be done under different machining parameters.

The results can be summarized and the critical values of machining parameters for which excessive

vibration is produced can be obtained for a specific machine.

This paper deals with the mathematical analysis of the drilling operation where vibrations due to

‘drilling’ are solely considered and values of critical machining parameters for ‘THAKUR PELTER

DRILLING MACHINE’ are calculated.

II. NEED OF VIBRATION ANALYSIS DURING DRILLING OPERATION

• Phenomenon of ‘chatter’ is widely observed during drilling operation.

• Vibration Analysis is the best solution to predict this complex phenomenon.



• Due to vibrations produced by drill dimensional accuracy of the hole gets affected. E.g.

Transverse Vibration of 0.3 mm amplitude can result into enlarged hole of 0.6 mm

excessive diameter.

• Vibration during drilling operation affects the surface finish of the hole produced.

• Assembly problems can be raised if the improper surface finished or enlarged holed

workpiece is required to assemble with other.

• Operational Problems can be raised if such part is installed on site e.g. tube and shell heat

exchanger if the size of holes on baffles is enlarged then loosening of it may happen when

fluid is flowing above them.

III. SOURCES OF VIBRATION DURING DRILLING OPERATION

In Drilling Operation two types of vibrations are observed:

A. External Vibrations

In drilling operation spindle of drill may vibrate because of the vibration developed by machine due to

malfunctioning. These vibrations can be categorized as vibrations due to external parameters. Sources

of external vibrations are as follows:

• Shaft Misalignment in spindle, motor, nut-bolts and transmitting elements viz., pulley or gear

drives

• Improper Foundation of machine

• Loosen fasteners such as nut-bolts, clamps etc.

B. Internal Vibrations

Internal Vibrations in the drilling operation are produced due to ‘drilling process itself!. Internal

vibrations are unavoidable as they occur because of internal characteristics of the system. Sources of

Internal Vibrations are as follows:

• Spindle Speed

• Force exerted by workpiece in opposite direction to the drill motion

• Resistive torque by induced by workpiece during material cutting

• High feed rate

• High Overhung of drill

IV. TYPES OF VIBRATIONS PRODUCED DURING DRILLING OPERATION

A. Vibrations in the drilling operation are produced in the two stages:

1) When the drill is rotating and approaching towards workpiece



Fig 1 Drill has not entered into the work piece

2) When the drill is rotating and drilling a hole into the workpiece

Fig 2 Drill has entered into the work piece

B. Following types of vibrations needs to be considered for drilling operation:

1) Free Vibration: Free vibration of the system helps to determine natural frequency of the system

(ωn).



2) Forced Vibration: Forced vibrations are produced because of rotation of spindle. These

vibrations have frequency of external excitation (ω) which is nothing but spindle speed in rad/sec.

In forced vibration we have to consider force applied by the machine on the tool in no loading

(Stage 1) and resistive force applied by the workpiece during drilling operation (Stage 2).

V. THEORY PART (MATHEMATICAL ANALYSIS)

A. Assumptions

1) Only the vibrations produced because of machining are considered. Effect of external

vibrations is neglected as these vibrations can be controlled with various techniques. On the

other hand internal vibrations which we are analysing can be controlled only by adopting safe

machining parameters.

2) During analysing of particular type of vibration, only that type is assumed to be taking place.

Effect of the other types is neglected for that analysis

3) We have considered cylindrical drill bit for the analysis as our scope is to find out the

vibrations that are going to take place not the cutting operation which is being carried out.

4) During our analysis our main focus is concentrated on the transverse vibrations. This is

because of the fact that the transverse vibrations produced during drilling operation are the

main cause of the enlargement of the diameter of hole being produced beyond tolerance limit.

B. Actual Procedure

1) For the drilling operation following three types are observed:

• Transverse Vibrations

• Longitudinal Vibrations

• Torsional Vibrations

Fig 3 Types of vibrations

2) Following procedure essential for Vibration Analysis of the drilling operation:



o Identification of the type of vibrations produced during machining operation

o Determination of the factors affecting these vibrations

o Applying concepts of the equilibrium to solve the problem

o Finding out the forces that are exerted on the tool under various conditions

LIST OF SYMBOLS:

d = Diameter of drill

l = Length of drill

E = Young’s Modulus

σ = Tensile Strength

τ = Shear strength

ω = Frequency of vibration

ωn= Natural Frequency

ωt = Frequency with which spindle is rotating

V = Tangential velocity of drill

r = Radius of drill

F = Force

ξ = Damping ratio

A = Amplitude of excitation

B = Amplitude of support

• Longitudinal Vibrations

1) Free Longitudinal Vibration Analysis:

Free longitudinal vibrations exist in the drill which are produced due to self-weight of the drill. These

vibrations can be analysed with the help of the following formula:

ωn= rad/sec

ωn= Hz

However these vibrations are not useful when we want to analyse the ‘chatter’ phenomenon of the

drilling operation.

Hence these vibrations are not considered during preparation of our table.

2) Forced Longitudinal Vibrations Analysis:

Cases:

1) When the drill is rotating and approaching towards work piece

Forced Longitudinal Vibrations do not exist when drill is approaching towards the work piece. It

is because of the fact that as drill is approaching, no force acts on the drill in the upward direction.



Due to this, the vibrations of the drilling during approaching towards the workpiece can be

neglected.

2) When the drill is rotating and drilling a hole into the work piece.

When drill touches the work piece and starts cutting the material to produce the hole, the upward

resistive force acts on the drill because of the tensile stress of the work piece material.

When the material breaks during drilling the hole, its failure in the longitudinal direction can be

considered as the compressive failure.

The force exerted in the upward longitudinal direction during the failure of the workpiece can be

calculated using the following formula:

F=

The amplitude of the forced longitudinal vibration can be computed using the formula given below[5]:

1 2ξ ωω

1 2ξ ωω

For our drilling machine we have considered no damping condition (since we want to consider the

worst possible case)

i.e. ξ 0 1

1

However, these longitudinal vibrations can be restricted with the help of restricting spring or suitable

damping mechanism. These vibrations however, do not effect on the diameter of the hole produced.

In Thakur Pelter Drilling Machine, which is used for very simple applications, these vibrations can be

neglected since this machine is generally practiced to produce through holes only.

• Torsional Vibrations

1) Free Torsional Vibration Analysis:

Free torsional vibrations exist in the drill which can be computed as follow:

ωn= rad/sec

but,

kt=



I=mk2=

ωn=

m=ρ*volume of drill

m=ρ* *l

ωn=

ωn= rad/sec

These vibrations are useful to determine torsional natural frequency of the system (ωnt)

This frequency is useful to obtain the forced natural torsional frequency of the system.

2) Forced Torsional Vibration Analysis:

Cases:

1) When the drill is rotating and approaching towards work piece.

No resistive force exerts on the drill in torsional direction when drill is approaching towards the work

piece and hence the vibrations produced can be neglected.


When drill enters into the work piece and starts cutting the material, torsional shear failure of the

material takes place.

Force exerted on the drill material during torsional failure of the work piece material can be

computed as below:

F=

Where,

F= T

Torque exerted is related with power in the following manner:

P= π T

Torsional Vibrations are created because of the rotary motion of drill. These vibrations create resistive

twisting moment on the drill and higher values of these vibrations may break the drill.



Formula for finding amplitude of forced torsional vibration ( ) is given as:

Considering value of damping to be negligible,

However as these vibrations do not affect in the transverse direction of motion which is responsible

for the enlargement of the hole. Thus it is not considered in the calculation.

• Transverse Vibrations

1) Free Transverse Vibrations Analysis:

Fig 4 Free transverse vibrations in any body[2]

The Vibrations in the drill in free state i.e. w/o rotation can be assumed as free transverse vibrations

(as in case of compound pendulum)

The Natural Frequency of the free transverse vibration (ωn) can be computed by using following

formula:

ωn

But, mass moment of inertia,

2 4

ωng



ωn=.√

2) Forced Transverse Vibration Analysis

Cases:

1) When the drill is rotating and approaching towards work piece

When the drill approaches towards the work piece, the no external force on the drill except the force

of vibration developed by the motor torque.

And thus these vibrations can be neglected because there is no restricting force acting on the drill bit

in the direction of the transverse vibration of the drill.


When drill enters into the workpiece, the force is exerted by the workpiece material on the drill bit in

the direction of the transverse motion of the drill. i.e. perpendicular to the axis of the drill.

The analysis of this force can be understood from the following diagram:

Fig 5 Force analysis during transverse vibration

The drill and work piece are considered to be attached with the help of the spring whose stiffness is

‘k’.

Under equilibrium conditions,

k = σ*v

This is because of the fact when the drill transverses with the linear velocity ‘v’, the force is exerted

on the drill in the direction of the transverse motion due to the stress induced in the material.

Force is the resistive force applied by the work piece in the direction perpendicular to the axis of the

drill.

F=σ *π d *(feed/sec)

The forced frequency of transverse vibration can be computed with the help of following procedure:



N= rpm of the spindle

ωt= ;

Fig 6 Free transverse vibrations in any body

The relation between angular velocity and linear velocity of the drill cross section in the transverse

direction can be given in the following manner:

v= ω

Now consider, the length of the drill oscillating at forced transverse frequency of ′ω′ in the following

manner:

ω=

Now the amplitude of the transverse forced vibration when the drill enters into the workpiece can be

computed by using the following formula[3]:

1 2ξ ωω

For our drilling machine we have considered no damping condition (since we want to consider the

worst possible case)

i.e. ξ 0 1

1

IV. PRACTICAL APPROACH

SAMPLE CALCULATIONS (For N=92 rpm, feed = 4.6736 mm/min, drill diameter =3.175mm

DATA:

d=0.00317m

l=0.150m

E=4.461*109N/m2



σ=420*106N/m2 [4]

TO FIND OUT:

ω,ωn,K,F,A

SOLUTION:

For 92 rpm

ωt= 2*Π*N/60

= 2*Π*92/60

=9.63rad/sec.

Fig 7 Chart prepared for the workshop



ωn=3.835/√

=3.835/√0.150

=9.901rad/sec.

F=Π*d*(feed/sec)*σ

Feed/sec=((feed/rev)*N)/60 [1]

=(0.0508*0.001*92)/60

=7.789e-5m/sec

F = Π*0.00317*7.789e-5*420e6

=329.84N/sec

v = ωt*r

=9.63*0.00317/2

=0.015m/s

K = σ*v

=420e6*0.015

=63e5N/m

ω = v/l

= 0.015/0.150

= 0.1rad/sec

ω/ωn = 0.1/9.901

=0.01

A = (F/K)/(1-(ω/ωn)2)

= (329.84/63e5)/(1-0.012)

= 0.051mm

A=0.051 mm

Fig 8 Photograph with Workshop Superintendent near the Thakur Pelter Drilling Machine

along with the chart displayed



V. CONCLUSIONS

We used the straight and simplified approach in the analysis of the vibrations produced during drilling

operation on “THAKUR PELTER DRILLING MAHCINE”. We arrived to the conclusion that the

“chatter” phenomenon is produced due to the transverse vibrations of the drill, which adversely affect

the assembly problem. Longitudinal vibration only changes the length of blunt hole and does not

affect the though hole. Torsional vibration leads to the removal of the material from the workpiece

with the help of chisel edge and flanks on drill, but does not affect the dimensions of the hole. This

report is the best example to show that how the theory knowledge gained in the academic curriculum

can be effectively applied to the practical scenario.

ACKNOWLEDGMENT

We are thankful to R.G.I.T., Andheri, for giving us this platform to think over our regular academic

curriculum. During preparation of this paper, we got various guidelines from our professors in the

college, particularly; we want to thank Prof. Girish Dalvi and Prof. Shamim Pathan for their technical

support in our work. We are equally thankful to workshop superintendent Mr.Rajesh and workshop

supervisor Mr.Moreshwar for their support in our practical work.

REFERENCES

[1] Erik Oberg and Franklin D Jones, “Machinery’s Handbook”(28th Edition).

[2] F. B. Sayyad, “Mechanical Vibration”,Tech-max Publications.

[3] V. P. Singh,“Mechanical Vibration”,Dhanpat rai Publication.

[4] S. K. Hajra choudhury, A. K. Hajra choudhury and Nirjhar Roy, “Elements Of Workshop

Technology Volume -2 Machine Tools”

[5] S. S. Rao, “Mechanical Vibrations ”,Pearson publication

[6] Mr. Muhammad Munawar, “Optimization of Surface Finish by Considering the Effect of

Vibration in Machining Operations” [online].



DESIGN AND ANALYSIS OF RISER FOR SAND CASTING C. M. Choudhari, Nikhil S. Dalal, Akshay P. Ghude1, Pratik P. Sankhe, Ashutosh M.Dhotre

Mechanical Department, Fr.C.Rodrigues Insitute of Technology, Vashi, Navi Mumbai, India [email protected]

Abstract

Casting is one of the earliest metals shaping method known to human beings. It is one of the cheapest

methods for mass production of any part and can be effectively used to make complex shaped parts

which are not easy to manufacture by other production process. Casting process is subjected to many

defects and it is necessary to eliminate them. One of the main defects in castings is “Shrinkage Cavity”,

which can be eliminated by attaching a Riser to the casting. This paper describes the parameters to be

considered while designing a Riser of an optimum size to get higher Casting Yield. Theoretically

designed model has been analyzed thermally in ANSYS 12.0 simulation software to ensure that

shrinkage cavity is completely eliminated from casting.

I. INTRODUCTION

ASTING is a metal shaping process by pouring the molten metal into a mould and allowing it to

solidify. The resulting product can virtually have any configuration (pattern) the designer wants. Casting

consists of various parts like cope, drag, pattern, sprue, runner, ingates, riser, etc. The process consists of

design, solidification, shake out, finishing and heat treatment. Although casting is one of the cheapest

methods it is associated with many defects like shrinkage cavity (hot spot), cold shuts, misrun, etc. In

order to understand how a shrinkage cavity develops consider a mould of cube. Figure (a) shows a cube

which is completely filled with liquid metal. As the time progresses, metal starts loosing heat through all

the sides and as a result starts freezing from all the sides, equally trapping the liquid metal inside, as in

figure (b). But further solidification and subsequent volumetric shrinkage and metal contraction due to

change in temperature causes formation of void, as shown in figure (c). The solidification when complete,

finally results in shrinkage cavity, as in figure (d). An optimal design of riser will help in reducing hot

spots formation/ void formation/ shrinkage cavity by ensuring that molten metal can readily flow into the

casting when the need arises. To eliminate the defect of hot spot riser is used in casting. It helps to fill in

the cavity formed inside the casting.

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For design of patter following allowances were considered:

Shrinkage allowance[3]:

For 200 mm: 2.6 mm

For 40 mm: 0.52 mm

Draft allowance = 1.5° (on vertical sides only)

Machining allowance = 2 mm on each side

Tolerance = ± 1 mm

Details regarding the model:

Total surface area = 120835.92 mm2

Total volume = 1848597.301 mm3

Modulus = 15.29 mm.

Solidification time = 14.36 min.

Weight of the casting = 4.4089 kg

Design of gating system:

Pouring time =17.363 sec

Choke area = 98.46 mm2

Sprue bottom diameter = 12 mm

Sprue top diameter = 15 mm

Sprue height = 42.5 mm

Total area of ingates= 452.38 mm2



The design of riser was done using Caine’s method[1]. The height of riser was assumed to be 70 mm and

the height of riser neck was assumed to be 10 mm. Following formulae were used for finding the

dimensions of casting.

Volume of the riser = πr2h

Surface area = πr2+2πrh

Freezing ratio (X) = (Ac / Vc) / (Ar / Vr)

Where, Ac= Area of casting

Vc = Volume of casting

Ar = Surface area of riser

Vr = Volume of riser

Y = Vr / Vc

X = ((a) / (Y-b))-c

For aluminium:

a=0.1

b=0.03

c=1

The riser diameter by Caine’s method is 55.244 mm.

For actual practice, Riser Diameter, Dr = 60 mm.

According to a research paper on optimum design of riser[8],

Dn = 0.35 × Dr

Yield of feeder = (Vc) / (Vc+Vf+Vn)

= 90.176 %

Yield of casting = (Wc)/ (Wg+ Wf)

= 82.18 %

Where, Wc = weight of casting

Wg = weight of gating elements

Wf = weight of feeding elements

IV. SIMULATION

Simulation of casting was done to serve two main purposes. First, it was used to find the location of hot

spot. Second, it was used to find the optimum dimension of riser so that hot spot shifted into the riser[4].

The effect of sleeve and air gap was also studied using simulation. These studies were done using both

linear and quadratic elements and both free and mapped mesh was used.

The following properties were used for sand during the entire simulation:



TABLE I

PROPERTIES OF SAND

Conductivity 0.519 W/m K

Specific Heat 1172.304 J/kg K

Density 1495 kg/m3

The following properties were used for aluminium during the entire simulation:

TABLE II

PROPERTIES OF ALUMINIUM

A. Identification of Hot Spot

The top view of the casting was simulated in ANSYS 12 software. At the end of simulation the last

solidifying region was obtained.

1) Simulation using Linear Elements

For this study, PLANE 55 was used as the linear element. PLANE55 can be used as a plane element or as

an axisymmetric ring element with a 2-D thermal conduction capability. The element has four nodes with

a single degree of freedom, temperature, at each node.

The top view was modeled for free and mapped mesh as shown in the figure.

Temperature Conductivity [6] Enthalpy [7]

273K 234.43 W/m K 0 J/m3

820K 216.01 W/m K 1.5533 × 109

J/m3

933K 90.975 W/m K 1.7769 × 109

J/m3

1043K 94.786 W/m K 2.0574 × 109

J/m3



Fig. 3.Modeling of Casting with Free Mesh.

Fig. 4.Modeling of Casting with Mapped Mesh.



Then, the material properties were specified followed by meshing of geometries. The meshed geometries

with free and mapped mesh are shown below.

Fig.5 Free Mesh of Casting

Fig. 6 Mapped Mesh of Casting



After meshing, convective load was applied on the outer boundaries of the casting. The ambient

temperature was assumed to be 303 K. The initial temperature of molten aluminium was assumed 1043 K

and the initial temperature of sand was assumed to be 303 K.

The temperature time plot of various nodes for free and mapped mesh was obtained as shown below:

Fig. 7. Temperature Time Plot for Free Mesh

Fig. 8. Temperature Time Plot for Mapped Mesh



The animation was run for 1 hour and the location of hotspot for free and mapped mesh was obtained as

shown below:

Fig. 9. Location of Hot Spot in Free Mes

Fig. 10. Location of Hot Spot in Mapped Mesh

2) Simulation using Quadratic Elements

For this, study PLANE 77 and PLANE 35 were used as the quadratic elements. Same steps were followed

for simulation using quadratic elements. The results obtained after the simulation showed that the

minimum temperature in the entire casting drops below ambient temperature.



Fig. 11. Temperature Time Graph for PLANE 77 element

Fig. 12. Temperature Time Graph for PLANE 35 element

This is not possible as the minimum temperature specified during simulation was ambient temperature.

Consequently, these results were not taken into account during further simulations.



B. Finding Optimum Riser Dimensions

Once, the location of hot spot was identified, the next objective was to find the optimum riser dimensions.

For this purpose, following dimensions of riser were considered.

TABLE III

RISER DIMENSIONS

Sr. No. Riser Diameter Riser Height Neck Diameter Neck Height

1 30 mm 70 mm 10.5 mm 10 mm

2 40 mm 70 mm 14 mm 10 mm

3 50 mm 70 mm 17.5 mm 10 mm

4 60 mm 70 mm 21 mm 10 mm

The above risers were first modeled in ANSYS. These models were then meshed using PLANE 55

element and free mesh. The animation of these models yielded the following results.

Fig. 13. Location of Hot Spot for Riser with Diameter 30






It is clear from the above figures that the hot spot shifts into the riser for diameter of 60 mm.

C.Effect of Sleeve on Riser Diameter

An insulating sleeve was used around the riser to slow down the rate of transfer of heat from the riser. A

sleeve of 5 mm thickness was used around the riser of 50 mm diameter. The result of this simulation is

shown below:



Fig. 17. Location of Hot Spot for Riser with Sleeve

As seen from the above figure, sleeve helps in maintaining the riser hot for a longer time. As a result, a

riser of diameter 50 mm can be used instead of 60mm. this helps in increasing the casting yield.

D. Effect of Air Gap

The modeling of air gap in casting was done as follows:

Fig. 18 Modeling of Air Gap

After the modeling was completed the casting was meshed using free mesh.

An air gap is formed only after aluminium solidifies. As aluminium solidifies at 933 K, the simulation

was run from 933 K. The temperature time plot for various nodes was obtained as shown below:



Fig. 19. Temperature Time Plot for Casting with Air Gap

From the above graph, it is seen that the maximum temperature at the end of simulation is 737.711 K.

For comparison, a similar model without air gap was made and the simulation was run from 933 K. The

temperature time plot for various obtained is as follows:

Fig. 20. Temperature Time Plot for Casting without Air Gap



From the above graph, it is seen that the maximum temperature at the end of simulation is 716.708 K.

V. ACTUAL TRIALS

The values obtained from theoretical calculations for design of pattern, gating system & riser were used to

manufacture casting. The casting having riser diameter equal to 60 mm was found to be defect free. Also

a defect free casting was obtained when a sleeve of 50mm diameter was used.

Fig. 21 Plate casting

VI. CONCLUSION

• ANSYS is a good tool to carry out solidification simulation.

• The optimized Riser dimensions were validated by simulation results and actual trials.

• Using sleeve as a feed aid helped in reducing riser dimensions there by increasing the Casting Yield.

• Simulation using other Thermal Solid MID-SIDE NODE Elements (Plane-35 & Plane 77) yielded

absurd results & thus cannot be used for Transient Thermal Analysis in ANSYS.

• Results of Simulation of casting solidification with air gap between Sand & Metal prove that air acts

as an insulator for heat transfer, but the effect can be neglected as there is no appreciable difference

between the simulation results when air gap was not considered.

REFERENCES

[1] P.N.Rao, “Manufacturing Technology”, Tata McGraw-Hill Education, New Delhi, 2008.

[2] John Campbell and Richard A Harding, “Solidification Defects in Casting”, IRC in Materials, The

University of Birmingham.

[3] PSG College of technology, “Design Data Book”, PSG College of Technology, Coimbatore, 2005.



[4] Dr. Mohammad Al-Tahat, “Metal Casting and Foundry”, Jordan University, course no. 906412.

[5] D. Joshi and B Ravi, “Classification and Simulation based Design 3D Junctions in Castings”,

American Foundry Society, 2008.

[6] C.Y. Ho, R.W.Powell and P.E.Liley (1972) , “J. Phy. Chem. Ref. Data, vl”.

[7] B.J. McBride, S. Gordon and M.A.Reno (1993), “NASA Technical Paper 3287”.

[8] T. Nandi, R. Behera, S. Kayal, A. Chanda and G. Sutradhar, “Optimization of Riser size of

Aluminium alloy (LM6) castings by using conventional method and computer simulation technique”,

International Journal Of Scientific & Engineering Research, Volume 2, Issue 11, November-2011

International Journal of Students Research in Technology & Management Vol 1(2), April 2013, pg192-202


A GENERALIZED CODE FOR COMPUTING CYCLIC REDUNDANCY CHECK

Debopam Ghosh, Arijit Mitra, Arijit Mukhopadhyay, Aniket Dawn, Devopam Ghosh Electronics and Communication Engineering, Heritage Institute of Technology, Kolkata, India

[email protected], [email protected], [email protected], [email protected] , [email protected]

Abstract

This paper focuses on developing a generalized CRC code where the user can vary the size of the

generator polynomial [1] such as 9 bits (CRC-8), 17 bits (CRC-16), 33 bits (CRC-32), 65 bits (CRC-64).

The working of the code has been shown taking an example and the resulting simulations obtained are

shown.

I. INTRODUCTION:

Cyclic Redundancy Check [2] is a method adopted in the field of communication to detect errors during

transmission through the communication channel. The data transmitted can be of any size depending on

the type of data being transmitted. In this paper, we have designed a VHDL code which demonstrates

how the CRC process works on a codeword whose length can be changed by the user based on his

requirements and the necessary simulations can be carried out to verify the results.

Cyclic Redundancy Check (CRC) is an error detecting code in which a transmitted message is

appended with a few redundant bits from the transmitter and then the codeword is checked at the receiver

using modulo-2 arithmetic for errors. The message is then transmitted from the encoder and is received by

the receiver where a CRC check is carried out. This process helps to determine any errors in transmission

through the transmission channel. This entire process is demonstrated using Very high speed Integrated

Circuit Hardware Description Language (VHDL)[3]. VHDL is a hardware description language used in

electronic design automation to implement designs in systems such as field-programmable gate arrays.

All the statements are executed concurrently in VHDL.

II. PROCESS OF CRC IMPLEMENTATION:

Figure 1: Method of polynomial detection



The method of determining the polynomial is as follows:

Each value is considered as the coeffiecient of a particular term which is an exponent of x. The rightmost

bit is considered as the 0th, the next is the 1st, then 2nd and so on.

For example, 1011 would mean a polynomial of [(1*x0)+(1*x1)+(0*x2)+(1*x3)]=x3+x+1 (starting from

rightmost).

Figure 2: Block Diagram of Receiver and Sender

Figure 3: Bitwise Representation of the Encoder and Decoder

Considering a n-bit message is being transmitted and k is the number of data bits. According to the CRC

process, a particular polynomial has to be chosen and this polynomial is known as the divisor polynomial.

The message is treated as the dividend and the divisor polynomial is used to divide the message

polynomial to generate a remainder. The method used for this purpose is known as modulo-2 division[4].

In modulo – 2 division, carry bit in addition and borrow bit in subtraction generated from one particular

bit is not carried forward to the next bit. In other words, for subtraction process simple XOR can perform

the necessary operations. The message is augmented with (n-k) number of 0’s. Then the modulo-2

division is carried out and the remainder of (n-k) bits is generated. This remainder then replaces the (n-k)

0’s at the end of the message sequence and it is then transmitted.



Fig 4: Division in CRC Generator

At the receiver, the data bits appended with the remainder is received as the dataword. The

dataword is divided by the same generator polynomial to generate another remainder polynomial. If the

polynomial generated is 0, then it is considered as error free. Otherwise the received message contains

errors. The entire process is divided into two broad parts; ENCODER and DECODER. All the operations

related to transmission of the dataword are carried out in the encoder while the checking operations are

carried out in the decoder. For this reason, the encoder is known as CRC Generator and the decoder is

known as CRC Checker.

Fig 5: Division in CRC Checker with correct and erroneous codeword



Fig 6: Example of a CRC Division using Polynomial

III. ALGORITHM:

CRC GENRATION:

Step1: Input the message to be sent through port a.

Step2: Input the CRC polynomial/divisor through port b.

Step3: Define the output port x,t (x-> stores the redundant bits, t-> stores the message +

redundant bits).

Step4: Begin process and declare the required variables- u,v,w,y,i,j.

Step5: In the variable v store the message bits followed by (n-1) 0’s.

Step6: w= first n bits of v and u=CRC polynomial/divisor.

Step7: If the MSB of w is 1 then w = w xor u (divisor) else w remains unchanged.

Step8: Left shift w and discard the MSB.

Step9: The next bit of v (in case of 1st iteration (n+1)th bit from the beginning,2nd iteration

(n+2)th from beginning etc…) becomes the LSB of w.

Step10: Repeat steps 7-8-9 till the end of v is reached (there will be a single iteration after

LSB of v is be added to w).

Step11: Port x(redundant bits/remainder) = first (n-1) bits of w.

Step12: Port t = message bits + redundant bits.

CRC CHECK:

Step1: Input the received bits and CRC polynomial through port a and b respectively.

Step2: As before follow the steps to generate the remainder and store in port x.



Step3: If the remainder is all 0’s then the received message is error free and t=received

bits- redundant bits.

Step4: If remainder is not all 0’s then there is an error and the message is discarded so t= all 0’s.

CRC GENERATOR VHDL CODE

library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

use IEEE.STD_LOGIC_ARITH.ALL;

use IEEE.STD_LOGIC_UNSIGNED.ALL;

package my_package is

constant m:integer:=8;

constant n:integer:=4;

end my_package;

library IEEE;




use work.my_package.all;

entity crc_new is

Port ( a : in STD_LOGIC_VECTOR (m-1 downto 0); ---message bits

b : in STD_LOGIC_VECTOR (n-1 downto 0); ---crc polynomial

clk : in STD_LOGIC;

x : out STD_LOGIC_VECTOR (n-2 downto 0); ---redundant bits

t : out STD_LOGIC_VECTOR (m+n-2 downto 0)); ---message with redundant bits

end crc_new;

architecture Behavioral of crc_new is

begin

process(clk)

variable v:std_logic_vector(m+n-2 downto 0);

variable u:std_logic_vector(n-1 downto 0);

variable w:std_logic_vector(n-1 downto 0);



variable y:std_logic_vector(n-1 downto 0);

variable i,j:integer:=0;

begin

v(m+n-2 downto n-1):=a(m-1 downto 0);

for j in n-2 downto 0 loop

v(j):='0';

end loop;

u:=b;

w:=v(m+n-2 downto m-1);

for i in m-1 downto 0 loop

if(w(n-1)='1') then

w:=w xor u;

else

null;

end if;

y:=w;

w(n-1 downto 1):=y(n-2 downto 0);

if(i=0) then

w(0):='0';

else

w(0):=v(i-1);

end if;

end loop;

x<=w(n-1 downto 1); ---- redundant bits

t(m+n-2 downto n-1)<=a;

t(n-2 downto 0)<=w(n-1 downto 1);

end process;

end Behavioral;

RTL SCHEMATICS



Fig 7: Black Box view of C RC Generator

Fig 8: Internal connections of CRC Generator

CRC CHECKER VHDL CODE

library IEEE;




package my_package is

constant m:integer:=8;

constant n:integer:=4;

end my_package;



library IEEE;




use work.my_package.all;

entity crc_new is

Port ( a : in STD_LOGIC_VECTOR (m-1 downto 0); ---message bits

b : in STD_LOGIC_VECTOR (n-1 downto 0); ---crc polynomial

clk : in STD_LOGIC;

x : out STD_LOGIC_VECTOR (n-2 downto 0); ---redundant bits

t : out STD_LOGIC_VECTOR (m+n-2 downto 0)); ---message with redundant bits

end crc_new;

architecture Behavioral of crc_new is

begin

process(clk)

variable v:std_logic_vector(m+n-2 downto 0);

variable u:std_logic_vector(n-1 downto 0);

variable w:std_logic_vector(n-1 downto 0);

variable y:std_logic_vector(n-1 downto 0);

variable i,j:integer:=0;

begin

v(m+n-2 downto n-1):=a(m-1 downto 0);

for j in n-2 downto 0 loop

v(j):='0';

end loop;

u:=b;

w:=v(m+n-2 downto m-1);

for i in m-1 downto 0 loop

if(w(n-1)='1') then



w:=w xor u;

else

null;

end if;

y:=w;

w(n-1 downto 1):=y(n-2 downto 0);

if(i=0) then

w(0):='0';

else

w(0):=v(i-1);

end if;

end loop;

x<=w(n-1 downto 1); ---- redundant bits

t(m+n-2 downto n-1)<=a;

t(n-2 downto 0)<=w(n-1 downto 1); --- total message

end process;

end Behavioral;

RTL SCHEMATICS

Fig 9: Black Box of CRC Checker

Fig 10: Internal connections of CRC checker



IV. SIMULATION:

Fig 11: Simulation result of CRC generator waveform

Different input datawords have been sent at different instants of time. In the first instant, “10010011110”,

at the next instant ‘10010100111” and at the next instant, ‘10010101010” is transmitted from the encoder.

The different values like 1182, 1191, 1194 etc represent the input dataword in decimal.

Fig 12: Simulation result of CRC check waveform



At the decoder, we see that the remainder (t) is equal to a string of 0’s, showing that if the received

codeword (a) is same as that of the transmitted codeword (t) in the encoder, there is no error. Here, the

received codeword has been intentionally made to be equal to the transmitted codeword to show a

successful transmission.

V. CONCLUSION:

In this paper, the process of CRC generation and checking has been discussed in detail. The methods

applied to detect an error during transmission has been shown using simulation in VHDL. However CRC

has some limitations:

• CRC is only an error detecting method. It does not correct the errors.

• The divisor polynomial should be chosen carefully. The divisor polynomial has to be a multiple

of (x+1). If any random polynomial is chosen then it may result into wrong calculation of the

remainder (CRC).

REFERENCES:

1. Cyclic Redundancy Code (CRC) Polynomial Selection For Embedded Networks By Philip Koopman

and Tridib Chakravarty

2. CRC Cyclic Redundancy Check Analysing and Correcting Errors By Prof. Dr. W. Kowalk

3. VHDL basics By Raunak Ranjan

4. http://en.wikipedia.org/wiki/Cyclic_redundancy_check

International Journal of Students Research in Technology & Management Vol 1(2), May 2013, pg 203-206


ADAPTIVE WEB BROWSER Akshay Parashar1, Manish Mali2, Ranjeet Kumar3, Prof.SaritaAmbadekar

Department of Computer Engineering, K.J.Somaiya Institute of Engineering and

Information Technology, Sion (E) Mumbai-400 022

[email protected], [email protected],[email protected], [email protected]

Abstract

Web browser play important role in World Wide Web (WWW). We go through different website and

invest enough time searching relevant URL. The project deals with making a browser that will

assist a person to find relevant information satisfying long term recurring goals rather than short

term goals and describe our research on learning browser behaviour model for predicting the

current information need of web user. Depending upon the user sequence of browsing behaviour it

indicates the degree to which page content satisfies user’s need. Thus one’s search experience may

be used to help the next users to reduce their searching effort. So, through more and more

searching greater experience will be gained by browser. We deploy extensive use of machine

learning for the browser to learn user’s behaviour. By such model the searching ability of browser

becomes more efficient and faster thus resulting in an intelligent and adaptive web browser.

Key Words – Machine learning, WWW

I. INTRODUCTION

While the World Wide Web contains a vast quantity of information, it is often difficult for web users

to find theinformation they are seeking. A more usefulsystem would not impose this requirement on

the user, butinstead would predict the exact query to return a page tosatisfy the user’s current

information needs. We call such apage an information content page, or “IC-page” for short,and name

such a query as “machine query” since it is notproduced by the human being.Suggestions using a set

of “browsing features” to predict the user’s current information need, which can then be usedto find

relevant web pages by launching a Web crawler orquerying a search engine.

For the problem of predicting clicked hyperlink, thesimplest solution would be to have a binary-. In

this way some existing text-learning methodscan be used. In this case all the hyperlinks clicked bythe

user are considered positive examples. This partially alreadycaptures user interests. However, in many

cases userdidn’t click on a hyperlink just because the lack of timeand also probably didn’t find

interesting all the visiteddocuments.This approach could be adapted for the problem ofsuggesting

interesting hyperlinks, if we are prepared toaccept that all the documents visited by the user

wereinteresting to the user and that un-clicked (or random)documents are uninteresting. Of course, the



simple solutionto that would be to ask the user for documentrating but we do not want to put

additional work tothe user.

II. EXISTING SYSTEM

Currently, most users are employed withinformation retrieval techniques in the form of popularsearch

engines to find useful pages. While such techniqueshave been quite helpful, they still require a user to

provideexplicit input. Search engines can only work if the usershave intuitions about what keywords

they should use (i.e.,which words will cause the search engine to produce theinformation the user is

seeking). But sometimes the user isnot aware of her explicit need, or cannot figure out the rightquery

to locate the exact pages that she/he wants.

III.METHODOLOGY

The proposed system has the following process flow:

SEARCHING FLOW

PREDICTING CLICKED HYPERLINK

Start

Enter Keyword

If keyword found

Fetch result from search

engine

Store keyword in

DB

Fetch result from search

engine

Retrieval method

Display result

Display result

Merge

Learning Process



This approach could be adapted for the problem of suggesting interesting hyperlinks, if we are

prepared to accept that all the documents visited by the user were interesting to the user and that un-

clicked (or random) documents are uninteresting.

PREDICTING INTERESTING HYPERLINK

Predicting interesting hyperlinks can be performed by predicting clicked hyperlinks as described in

Section. Noise in the class value can be reduced by learning from the clicked hyperlinks (positive

examples) only. This would in our case require solving at least two additional problems:

(1) Finding an appropriate feature selection method, say the basis for hyperlinks to consider can be

the clicked hyperlinks(positive examples) and

(2) Proposing a suitable result evaluation.

Algorithms like association rule, naive bayes, k-means can be used to perform learning.

Additionally, features like number of clicks (how many times a hyperlink is clicked

corresponding to a particular keyword),time duration (time spend on a particular hyperlink),can

be taken into account.

IV. ALGORITHM

Step1: Start.

Step2: Get keyword from user.

Step3:If keyword exists then retrieve, from database the relevant links using retrieval module and also

from search engine.

Step4: If not then save keyword in database and display result using search engine.

Step5: Save clicked hyperlinks corresponding to the keyword clicked by user(positive links).

Step6: Apply Machine Learning methodology to database to generate interesting hyperlinks

pertaining to IC page.

Step7:Display theresults to user.

V. FUTURE SCOPE

To further help users browsing the Web, a profile can be induced for each user independently of other

users. This profile can be further used to compare different users and to share knowledge between

them. In order to secure the privacy, only knowledge and not the user identity can be exchanged or

even this cooperation could apply only for users that explicitly agreed to take part in knowledge

sharing.

On the other hand, some users might be interested in ’making friends’ with similar users and join the

list of users whose identity (eg. e-mail) is reviled to similar users from the list. This sharing of

knowledge is related to collaborative approach to intelligent agents design and methods used in multi-

agent systems. A way of cooperation between different users using the same system for user

customized Web browsing is on the model induction level. Namely, even though each user has a

separate user profile, they have a similar form. If we could infer from the user profiles some higher



level knowledge that is independent of a specific set of documents, that knowledge could be shared

between users. For instance, if we have given some background knowledge, find which part of a given

background knowledge is frequently used in different models (which higher-level attributes are

useful). That would be especially valuable for new users, where only a small set of documents is

available for the model induction. Sharing knowledge between different users of the system is out of

the scope of this paper.

Also, the results obtained from various search engines can be categorised to distinguish and validate

the effectiveness of information retrieval methodology used by them. This partially can be used as a

parameter by search engine to make relevant improvement in their searching algorithm.

VI. CONCLUSION

The paper proposes the methodology that helps user to retrieve IC page but only through long term

machine learning experience of browser. Distinguishing feature of proposed system is that

• The browser has a dedicated database to it and can provide user hyperlinks in offline mode.

• It reduces the dependency of user on search engines gradually gaining autonomy as an assistant to

help user.

• Since the processing of data takes place at client side the user is provided with relevant hyperlink

faster independent of server to which it seeks link.

• Apart from browser’s suggested links the user is not kept from results of search engine.

REFERENCES

[1]Adaptive Web Browser: An Intelligent Browser Md. Forhad Rabbi, Tanveer Ahmed, Anindya

Roy Chowdhury, Md. Ran-O-Beer Islam Department of Computer Science & Engineering Shah Jalal

University of Science & Technology Sylhet, Bangladesh

[2]Identifying Machine Query for an Intelligent Web Browser System Tingshao Zhu, Graduate

University ofChinese Academy of SciencesBeijing, China XinguoXu, National Computer System

EngineeringResearch Institute of ChinaBeijing, China Guohua Liu, Department of Computing

ScienceUniversity of AlbertaEdmonton, Canada

[3] Machine learning for better Web browsing DunjaMladeni, Dept. of Intelligent Systems,

J.StefanInstituteJamova 39, 1000 Ljubljana, Slovenia

[4]A Platform for Large-Scale Machine Learning on Web Design ArvindSatyanarayan, SAP Stanford

Graduate Fellow Dept. of Computer Science Stanford University 353 Serra Mall Stanford, CA 94305

USA Maxine Lim, Dept. of Computer Science Stanford University 353 Serra Mall Stanford, CA

94305 USA Scott R. Klemmer, Dept. of Computer Science Stanford University353 Serra Mall

Stanford, CA 94305 USA



AUTOMATIC FARMING SYSTEM 1Kailas Adhav, 2Abhilesh Wankhede

Vidyavardhini’s College of Engineering and Technology, Vasai Road (West) [email protected],

[email protected]

Abstract

Since Olden times man has been cultivating and depending heavily on the plant and crops to

arrange for the staple food. To do this he had to toil and severe with labor. As the technology

advances people wish for more and more comfort, reliability and fast operation. India is the

farmer’s country and major part of the revenue is generated out of the agriculture industry

Keeping the above ideology in mind this project propose to design a unit with following

features:1.ploughing 2.seedsowing 3.cutting etc. This study develop an Energy Saving Automatic

Farming System with two unit User unit (remote control) & Solar Powered Tractor Unit. From

user unit i.e. Wireless remote it gives instruction to the tractor unit to perform various task such as

plugging, seed sowing, cutting etc The required power supply for performing various task is

obtained from solar panel using tracking and trapping system to obtain maximum solar energy.

For automation of tractor unit it uses memory mapping which will be performed by microcontroller

in embedded c using Kiel software.

I. INTRODUCTION

The conventional sources of energies are limited & are nonrenewable source. Looking at today’s use

of energy, these sources are not going to last for more than 30 years from now. What will the world

do, after these sources are exhausted? The ultimate source of energy then will be non-conventional

sources of energy. These sources are renewable type. As much as you use, it will always remain. Sun

will never stop rising/ shinning. In the twenty-first century, consumption of energy has increased on

account of technological progress and population explosion. Hence scientist began to express the fear

that deposits of conventional fuels would be depleted in the near future the possibility of the

exhaustion of the sources of fuels is known as the ‘energy crises. The average solar energy radiated on

earth is 1.36 kWh (kilowatt hour) per square meter. This energy is equal to the energy that can be

obtained from 12 lakh crore tons of coal & is 20 times the amount of energy that can be obtained from

the total coal deposits available on the Earth So this project “automatic farming system” which will

harness the solar energy and will be use for agriculture purpose in a unique and innovative way.

A. What is Robot?

A robot can be defined as a reprogrammable, multifunctional manipulator which is designed to move

material, parts, tools, or specialized devices through various programmed motions to perform a

variety of tasks.

B. Features of Project:

The designed solar powered tractor has following features:



1. It has tools for performing various agricultural tasks like

• cutting

• plugging

• seeding etc

2. This posses a solar panel for saving diesel & petrol cost.

3. Tractor has memory in which it will store information about tracks, fields, etc.

4. We can add Wireless camera & GPS module for video surveillance & positioning. (optional)

II. BLOCK DIAGRAM

The block diagram of the project is mainly divided into two sections:

• User Unit (RF transmitter to control tractor.)

• Tractor Unit (RF receiver on tractor and solar trapping system).

A. Solar powered Robotic Tractor:

• The tractor has various mechanical tools for performing different agricultural task like seeding,

cutting, plugging etc.

• The tractor is also equipped with various sensors to detect & avoid obstacle, fire etc.

• The operation of tractor is control via wireless remote provided with user.

• Tractor will use inbuilt memory to store track information, field information etc.

B. Wireless remote to control Robotic tractor

Fig.1

The transmitter used here is to control the tractor from a distant place. The data send from the

switches is in parallel form and the transmitter module accepts the data in serial form. The Encoder

will convert the parallel data to serial data and data will be given to transmitter.

C. Robotic Tractor with solar trapping system

The receiver module here will receive the wireless data send by the transmitter. The decoder will

convert the serial data from module into parallel data. These parallel data is given to the motor driver

to control the motor for navigation purpose and seed feeder.

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1. Mars exploration robot was autonomous solar powered robot.

2. This principle can be used in day to day life in cars and automobiles.

3. Apart from the robot solar tracking and tracing can be used in industries, for home use.

V. ADVANTAGES

1. No fuel required as the robot is battery powered.

2. No external charging of battery is required as charging is done by the solar panel placed on

the robot.

3. The tracking trapping of solar energy can be used for home appliances.

VI. FUTURE SCOPE

In future we will try to improve this project & try to implement a trolley also. So this will fulfill

complete kit for a former. Also we will try to make it more intelligent & autonomous.

VII. CONCLUSION

This paper proposed an idea of automatic farming system lucrative advancement in the field of

technology. The project we implemented, reduces man power and saves the conventional energy

sources by performing various tasks of farming automatically & helps a farmer in his day to day work

performing rapidly & effectively with the help of this system.



REFERENCES

1. RFID Handbook Fundamentals and Applications in Contactless Smart Cards and

Identification by Klaus Finkenzeller, Wiley and Sons publications.

2. RFID Field Guide: Deploying Radio Frequency Identification Systems By Bhuptani Manish.

3. AIM, Inc. Shrouds of Time: The History of RFID. By Dr. Jeremy Landt

4. Finkenzeller,Klaus. RFIDHandbook1. Second Edition. Chic ester, England: John Wile &

Sons, Ltd. 2004.

5. Sharma, Sanjay E., Stephen A. Weis, and Daniel W. Engeals. RFID Systems and Security and

Privacy Implications

6. Texas Instruments – RFID support

7. http://www.ti.com/tiris/default.htm

8. RFID Forumhttp://www.rfidtalk.com/

9. All datasheet - Datasheet search site for Electronic Components http://www.alldatasheet.com/

10. AT89S51 MCUs overview http://www.atmel.com/dyn/general/tech_doc.asp?doc_id=7190

11. Voice module: APR9600

International Journal of Students Research in Technology & Management

Vol 1(2), April 2013, pg 214-219


KUNAL ASTROCRYPTOGRAHY SECURITY USING DISTANCE FORMULA AND 3D GEOMETRY

Kush Jain

Department of IT, Army Institute of Technology, Pune, Maharashtra, India

[email protected]

Abstract

In real world, data security plays an important role where confidentiality, authentication, integrity,

non repudiation are given importance. The universal technique for providing confidentiality of

transmitted data is cryptography. This paper provides a technique to encrypt the data using

distance formula and 3D geometry.

Keywords - Distance Formula, 3D Geometry, data security, authentication, cryptography, ASCII

I. INTRODUCTION

In the present world scenario it is difficult to transmit data from one place to another with security.

This is because hackers are becoming more powerful nowadays. To ensure secured data transmission

there are several techniques being followed. One among them is cryptography which is the practice

and study of hiding information. [1]

In the modern era of computers we can create more secure cipher text. In this paper we create cipher

text using ASCII values of characters and 3D Geometry.

II. LITERATURE SURVEY

A. Cryptography

Cryptography, to most people, is concerned with keeping communications private. Encryption is the

transformation of data into some unreadable form. Its purpose is to ensure privacy by keeping the

information hidden from anyone for whom it is not intended. Decryption is the reverse of encryption;

it is the transformation of encrypted data back into the same plain text from which the cipher text was

generated. [1]

Encryption and decryption require the use of some secret information, usually referred to as a key. [1]

The data to be encrypted is called as plain text.[1] The encrypted data obtained as a result of

encryption process is called as cipher text.[1]

B. 3D Geometry


Vol 1(2), April 2013, pg 214-219


A point in 3D plane can be represented using 3 coordinates (x, y and z). A point on a sphere of radius

r and center (x0,y0,z0) can be represented as[3]

x =x0 + r × cosθ × sinφ

y =y0 + r × sinθ × sinφ

z =z0 + r × cosφ

Where 0 <= θ <= 2 π, and - π /2 <= φ <= π /2

C. Distance Formula

Distance between two points A (x1, y1, z1) and B(x2, y2, z2) can be calculated as [2]

Distance

212

212

212 )()()( zzyyxxd −+−+−=

212

212

212

2 )()()( zzyyxxd −+−+−=⇒

III. PROPOSED METHODOLOGY

In this method the first step is to assign a unique set of coordinates known only to receiver and sender.

These coordinates are the origin of the Cartesian plane they are going to use for communication

Another set of points known as stars should also be shared only between the sender and receiver.

There should be at least 1 star. A constant m which signifies the maximum number of concentric

spheres to consider is also decided. E.g. m = 10

Fig. 1 Multiple Stars


Vol 1(2), April 2013, pg 214-219


Another set of spheres (specifying the radius and the center point (which should not enclose the

sphere made by taking any stars center point and radius as the m × maximum range of ASCII)) known

as black holes is also shared between the sender and receiver. There can be any number of such

spheres (black holes) (The only restriction being that there is a possibility to encode all ASCII

characters using stars)

Fig. 2 Blackholes

The next step is to calculate the ASCII equivalent of each character in the message and add it with any

multiple of the range of ASCII characters. Let’s call this value d

Then we plot a point on the sphere with any star chosen at random from given stars and radius d. The

point is plotted by taking any random value of θ and φ.

Fig. 3 Position of letter A


Vol 1(2), April 2013, pg 214-219


We check if this point lies inside or on any black hole. If it does then we regenerate the point by going

back to step involving generation of point.

Fig. 4 Points inside blackhole are ignored at the time of decryption

We check that if this point already exists in the cipher text. If it does then we regenerate the point to

get a different set of coordinates by regenerating the point by going back to step involving generation

of point. If we keep getting the same result after trying many times, then only we repeat the point.

We now check if this point is closest to the star from which it is generated in comparison to other

stars. If not, then we regenerate the point by going back to step involving generation of point.

Now we round the point to 2 decimal places and remove the decimal point and append it in cipher text

by separating the coordinates with a comma.

While generating points for each character, we also place any random number of points that lie in or

on the black hole at the starting, in between or at the end of cipher text to generate a certain number of

points that lie in or on the black hole

To decode it, first retrieve the triplet from cipher text each of which is separated by comma. Then

divide each number by 100. This will be the x, y and z values of the point.

Check if this point lies on or inside a black hole, if it does then generate nothing.

If it does not come in or on a black hole then find the star closes to this point and the distance of that

star from this point. Round off this distance to nearest whole number. Take remainder by dividing this


Vol 1(2), April 2013, pg 214-219


rounded distance with the maximum range of ASCII characters. This remainder is the ASCII

equivalent of plain text character. Convert this ASCII value to character to get the plain text

The entire coordinate system has origin which is shared just between the sender and receiver

Fig. 5

Station A,B,C have same stars and blackhole but it is difficult for them to see messages meant for

other station as they have different origin

IV. ADVANTAGES

1. Since it uses ASCII, it can encrypt any character including A-Z, a-z, 0-9, spaces as well as special

characters supported by ASCII[4][7]

2. Since it generates random points on a sphere of random radius for a particular character. There can

be 360×180×m points for a particular character by trying not to repeat the same point again for the

same character.

3. It generates random useless points in between, thus fixed size messages can be generated providing

more security compared to other cryptographic algorithms[5][6][1] as the number of characters in

original message cannot be found from encrypted message without the knowing the black holes


Vol 1(2), April 2013, pg 214-219


4. There can be many stars, thus even if only 1 star is leaked, the message can only be partially

decrypted

5. The receiver also needs to know the origin; if he does not know it then it is difficult to read the

message

6. Message cannot be decrypted completely till all the stars and origin are known

7. Even if the algorithm is known, it is almost impossible to extract the original text without knowing

the stars and origin

8. Even with the same set of stars, blackholes and origin , we get many different points for the same

character, thus making it more secure.

V. CONCLUSION

The above cryptography can be applied mainly in military where data security is given more

importance. Instead of ASCII Unicode can also be used, which would provide the ability to encode

and decode messages in one’s native language and thus increasing security. Thus usage of stars, black

holes and origin ensures that the data is read only by authorized personnel

REFERENCES

1. S. Pavithra Deepa, S. Kannimuthu, V. Keerthika ,“Security Using Colors and Armstrong

Numbers”, Proceedings of the National Conference on Innovations in Emerging Technology-

2011 Kongu Engineering College, Perundurai, Erode, Tamilnadu, India.17 & 18 February,

2011.pp.157-160

2. An article on Distance http://en.wikipedia.org/wiki/Distance

3. An Article on Sphere http://en.wikipedia.org/wiki/Sphere

4. An article on ASCII codes http://en.wikipedia.org/wiki/ASCII

5. Dr.M.Mohamed Sathik, A. Kalai Selvi, ” Secret sharing scheme for data encryption based on

polynomial coefficient”, 2010 Second International conference on Computing, Communication

and Networking Technologies

6. Mohammad Zakir Hossain Sarker, Md. Shafiul Parvez , “A Cost Effective Symmetric Key

Cryptographic Algorithm for Small Amount of data”

7. Ahmed Desoky, “Cryptography: Algorithms and Standards”, 2005 IEEE International

Symposium on Signal Processing and Information Technolog



PROPOSED CRYPTOGRAPHIC ALGORITHM FOR IMPROVING DATA SECURITY

Dipankar Som

Kalyani Government Engineering College, Kolkata, India

[email protected]

Abstract

Cryptography is a Greek word which means secret writing. However we use this term to refer to the

science and arts of transforming the message to make them secure and immune to attacks. Access

to stored information has increased greatly. More companies and institution store official and

individual information on computer than ever before. So information security is a matter of deep

concern. In this paper I have proposed an algorithm which is based on block cipher concept. In

this algorithm I have used simple mathematical operations like XOR and shifting operations.

Speed and complexity are two important aspects of block ciphers. The block length of the

block cipher decides the complexity. The key complexity also imposes a constraint on the length of

the block cipher. In my proposed work the keys are generated by a random key generator and a new

approach for S-box is used.,

Key words: Internet security, Encryption, Decryption, Cryptography

I. INTRODUCTION

Plain text & Cipher text:

The original message before being transformed is called plain text. After the message is transformed

on the application of algorithm is called cipher text.

Cipher

We refer to encryption and decryption algorithm as ciphers. The term ‘cipher’ is also used to refer to

different categories of algorithm in cryptography.

Key

A key is a number (or as set of numbers) that the cipher as a number operates on.

II. CATEGORIES

We divide the entire cryptographic algorithm (ciphers) broadly into two groups:-

1. Symmetric- Key cryptographic algorithm.

2. Asymmetric-Key cryptographic algorithm.



Figure 1: A conventional model of Cryptography

Symmetric-Key Cryptography

In the symmetric key cryptography the same key is used by both parties. The sender uses this key as

an algorithm to encrypt data; the receiver uses the same key and corresponding decryption algorithm

to decrypt data.

Asymmetric-Key Cryptography

In the asymmetric key cryptography there are two keys: a private key and a public key. The private

key is kept by the receiver. The pubic key is announced to the public.

Let us discuss something about the traditional ciphers which are though obsolete but helped in the

evolution of the modern ciphers.

III. TRADITIONAL CIPHERS

We divide traditional ciphers into two broad categories:-

1. Substitution ciphers.

2. Transposition ciphers.

Substitution Cipher

A substitution cipher substitutes one symbol with another. If the symbols in the plain text are

alphabetic character we replace one character with another.

Transposition ciphers

In transposition ciphers there is no substitution instead their location alters. A character in the first

position may appear in the different position in the cipher text.

IV. MODERN ROUND CIPHERS



These ciphers are bit oriented.

XOR cipher

It uses the exclusive-or operation between two data inputs; plaintext as the first and the key as the

second.

Rotation cipher

This cipher rotates the input bit left to right. It may be keyed or keyless.

S-box

An S-box (substitution box) parallels the traditional substitution cipher for characters. The S-box is

normally keyless and is used as an intermediate stage of encryption and decryption.

P-box

A P-box (transposition box) for bits parallels traditional transposition cipher for characters. It

performs a transposition at bit level; it transposes bit.

V. PROPOSED ALGORITHM (EXPERIMENTAL DESCRIPTION)

The proposed work is mostly based on a class of Feistal Ciphers technique in which the encryption

and decryption process are very similar even identical in some cases requiring only a key reversal.

Thus the size of the code and circuitry required to implement such a cipher is almost halved.

The basic steps involved in my proposed work are:-

1. Bit-Shuffling

2. Substitution boxes or S-boxes.

3. XOR operations to create a large amount of data.

Successful block cipher design integrates the concept of Confusion and Diffusion. Essentially looking

at the output no idea can be made about the input, in other words input should not bear a statistical

regularity with the output. Confusion is the measure of the statistical relationship of the input on the

output. Diffusion, on the other hand is the tendency to extend the influence of the input symbols on

the output words to alienate the tendency of the input symbols on the plain text.



256 –bit Plain text

Plain Text

Split (64*4)

64 bit 64 bit 64 bit 64 bit

XOR XOR XOR XOR

DES DES DES DES

Random Key

Generator

Merge (256 bit)

Substitution Box or S-box

Start

Cipher‐text

END



Steps of Proposed Algorithm

1. Firstly a 256 bit text is obtained as the plain text.

2. Next the 256 bit text is divided into four arrays (64*4) using permutation or bit-shuffling.

3. The keys are generated as different lengths (64,256) from a random key generator and are not

entered manually.

4. Now the plain text is XOR-ed with the key generated.

5. Next the 64 bit text is passed through the DES block with the keys generated from the key

generator.

6. Now the four arrays of 64 bit text is merged into the 256 bit text and subsequently passed

through the S-boxes to obtain the cipher text.

7. In the substitution step (S-boxes) the substitution occurs in presence of the random key

generated from the key generator.

VI. RESULTS & CONCLUSION

In this proposed algorithm it has been found that the speed and complexity of this block

cipher is better than the DES algorithm, while due to its Freisel mode of operation the code

and circuitry of this are very similar to each other. The S-box function of DES is an 8-tick

time consuming function because there are 8 s-boxes perform serially. In the proposed

algorithm, the s-box is take a 1-tick time consuming function because there is 1 S-box

perform in parallel-wise each of rows to calculate the output.

The complexity of any block cipher depends on the block length or key length unless special

break through is done. The DES deals with 64 bit and so the complexity is 264 while the

complexity of the proposed algorithm is 2256.

REFERENCES

[1] Norman D. Jorstad “Cryptographic Algorithm Metrics”, January, 1997, pp. 1-10

[2] Prof. Dr. Hilal Hadi Salih & Dr. Ahmed Tariq Sadiq, “Proposal of new block Cipher Algorithm”,

pp. 10-18.

[3]Bhaskaran Raman, “Cryptography & Network Security”, IIT Kanpur, May 2005

[4] “Feistel Cipher”, Wikipedia, the free encyclopaedia Retrieved from http://www. Wikipedia .org.

[5] Vishwa gupta, “International Journal of Advanced Research in Computer Science and Software

Engineering”, Vol. 2, Issue 1, January 2012, pp. 1-3.

[6] Behrouz A. Forouzan, “Data Communication and Networking”, Fourth Edition, pp.968-1030



WEBO-KIT: AN ENHANCED WEB UI TOOLKIT Sukeshni Kantrod, Kanchan Jondhale, Purva Kshatriya, Namita Maharanwar

UG, Department Of Computer Science, Pune Institute of Computer Technology, Pune, India. [email protected], [email protected], [email protected],

[email protected]

Abstract

Designing UI and backend are one of the main aspects of Web application development.

Developers waste a lot time in designing tool like tree view, grid view etc. one by one whenever

required as per the requirements of application. Solution to these problems are building UI toolkit

library containing commonly required tools, include that library and drag-drop the tool while

building application. The existing UI toolkits have less number of tools and do not contain each

and every tool, have a lot of ambiguities in their behaviour pattern, look-feel, large in size and have

cross browsing problem.

There is a need of powerful UI toolkit which will have all necessary tools, consistent behaviour

pattern and light in weight. If we compare same tool from different libraries, they may have

different properties which can be combined under one library as a feature rich library.

Our objective is to combine all the properties of a tool from different available web UI toolkits like

kendo, dojo, jQuery UI, YUI etc., providing consistent behaviour pattern, look-feel, cross browser

support, add new features and light in weight. On the basis of analysis done on various available

toolkits, feature rich and configurable library of commonly used tools is being created.

Key words: Cross browsing

I. INTRODUCTION

A good UI is a must for correct interpretation of information by user therefore it should be well

mannered. Developers waste a lot time in designing a particular tool whenever required as per the

requirements of application. This was very time consuming procedure. Then developers find a library

containing collection of all necessary tools. Developer has to just include that library in their

application and drag-Drop the tool while building application. But there is no such toolkit which has

all necessary controls in it.

Developers first decide which tool they will require in their application. As per the requirement of a

particular tool, developers analyze different toolkits to get the best tool amongst them in terms of

behavior, look, functionality, etc. but they didn’t get such toolkit satisfying their needs. Therefore,

they have to refer at least 2-3 toolkits for building application, resulting in the increase of size of



application. Also, this result in lot of ambiguities in their behaviour pattern, look-feel, as the skin of a

tool from different toolkit is different.

II. ANALYSIS OF EXISTING TOOLKIT

Every toolkit has its own advantages and disadvantages. The main motto is to create a new library

having combination of advantages of all toolkits into one and build that library on top of existing

jQuery based libraries. For this purpose it is necessary to analyse all the possible toolkits considering

the parameters like size, look-feel i.e. cross browser support. Amongst them, some are based on jQuery

and some are non jQuery based. As the jQuery itself is very light in weight, therefore more stress is

given on jQuery based libraries. The list of analysed toolkits is as follows:

1. Kendo UI Toolkit from Telerik

2. Infragistics

3. YUI

4. jQuery UI

5. DOJO

Figure 1: kendo Drop down control

Figure 1 shows kendo’s dropdown control where the orange colour is not suitable at enterprise

level.

III. COMPARATIVE STUDY

Table 1: Comparative study of toolkits



According to chart in Table 1, jQuery UI is smallest in size, kendo has better looking in UI,

Infragistics and YUI are very large in size and have average looking UI. Jquery UI lacks largely

required controls like grid view, tree view etc. it consists of basic controls like button, checkbox etc.

All the toolkits provide cross-browser support.

By observing the data mentioned it is clear that kendo toolkit has average size and better looking UI

as compared to other toolkits.

IV. WEBO-KIT: THE PROPOSED TOOLKIT

The proposed toolkit has following characteristics -

• Small in size.

• Cross browser support

• Better UI

• Collection of majorly used tools

• Reduced skinning problem

The enhanced library will contain commonly used tools like Grid control, tree view, tab view, modal

dialog, buttons, textbox, combo box, radio button, generic web control, check button calendar control,

collapsible panel, menu bar progress bar and many more so that the developer will require refer only

one library for the application to be developed.

Web controls

Figure 3: WEBO-KIT

V. DESIGN & IMPLEMENTATION

An analysis of a toolkit is done from various available toolkits and the one with the best amongst is

chosen as the base for further enhancement of UI properties and features. Some new features that can

be added are ascending and descending order, sorting on the basis of character at the start and end of a

data word.

Inputs from web developers for proper colour to be chosen for better data interpretation at enterprise

level is been taken.

On the basis of result obtained after analysis, a proper colour, feature, properties are added to the

basic tool available. ASP.net framework is used for the development of a particular tool. The

technologies used are jQuery, HTML5, CSS3, ajax and JSON for developing a tool. The data required

by the tool is provided using web service which can provide hard-coded data or can retrieve data from

some data storage like MySql database for demo purpose. The web service is located at any server so

Client side control

Enhanced properties

Standardized web UI toolkit



that any client can have access to it. This makes the data in a tool and UI of a tool separated from each

other.

The UI controller i.e. the view of the tool, the data provided are separate from each other. Hence the

tools support MVC (modal view controller) form which keeps the implementation and the data source

separate from each other.

Reference of web service is provided to the asp.net project as a data provider.

Figure 4: Data Grid View

For example GridView as shown in the Figure 4 the filtering feature can be obtained just by a click

on the key shown in column head, blue colour is chosen for interpretation of data selected, a click on

the view details button will give all the details of the selected record in pop up form.

The notable thing about Webo-kit is the data shown in tools is retrieved through web service

dynamically from database.

VI. PERFORMANCE

Figure 5: Toolkit



The comparison chart shows the decrease in size of toolkit in regard with decrease in size of grid-view

and tree-view, tab-view, drop-down of toolkit designed as compared to infragistics’s toolkit. As the

size is small the loading time required for application in which this toolkit is used will be small.

VII. FORMAL MODEL

S = I, O, F, Sc, Fc

Input (I): Default.aspx

Output (O): library

Functions (F): UIdesign (), getData (), addProperties (), createLibrary ()

UIdesign (): Design UI of a particular tool.

getData (): Get data from webservice.

addProperties (): Add features/properties to the tool i.e. enhancement of tool.

For example in case of grid-view sorting, filtering etc. features are added.

In case of drop-down, checkboxes are added.

createLibrary(): To create a library of tools developed.

Success cases: Su= Sc1^Sc2

Sc1 → supports latest browsers (IE 7+, Chrome, and Firefox)

Sc2 → get correct data from web service

Failure cases:

Fc = Fc1, Fc2, Fc3

Fc1 → does not support older browsers

Fc2 → no data displayed, if data from web service is incorrect.

Fc3 → no output, if Default.aspx is not compiled correctly.

VIII. CONCLUSION

The proposed modified web UI Toolkit is easy to distribute compared to other toolkits that require

installation to function. Web UI toolkit is also useful for creating the templates which will be useful

for programmer to develop the application only by dragging these templates.

IX. FUTURE SCOPE

The future research is to provide user-specific customized properties window where user will have a

set of skins to be applied to the control. The user will be able to change the skin of control as per his

choice.



X. ACKNOWLEDGMENTS

We would like to take this opportunity to thank Professor Atish Londhe (the department of computer

science) at Pune Institute of Computer Technology, Pune for constant encouragement and assistance

he provided us at every stage of the project. We would also like to thank Dr. G. P. Potdar, Head of

Computer Engineering, Pune Institute of Computer Technology, Pune for his encouragement and

support.

REFERENCES

[1] Ganji, R.R.Mitrea, M.; Joveski, B.; Preteux, F. HTML5 as an application virtualization tool

Consumer Electronics (ISCE), IEEE 16th International Symposium on 4-6 June 2012

[2] Yang Jianping, Ahang Jie Towards HTML 5 and interactive 3D graphics, Educational and

Information Technology (ICEIT), 2010 International Conference on September 2010

[3] Mesbah, A. Mirshokraie, S. Automated analysis of CSS rules to support style maintenance.

Software Engineering (ICSE), 34th International Conference on 2-9 June 2012

[4] MDN website: https://developer.mozilla.org/en-US/

[5] Kendo website: http://kendoui.com



EFFICIENT MULTI HOP ROUTING ALGORITHM FOR BLUETOOTH

DEVICES

Ganesh Gupta1, Shubham Gupta2, Manish Kumar Singh3, Durbadal Chattaraj4

1,2,3,4Department of Computer Science & Engineering,

Narula Institute of Technology, Agarpara, Kolkata, West Bengal, India [email protected], [email protected], [email protected],

[email protected]

Abstract

On wireless ad hoc network (AHN), ad-hoc mode is a method for wireless devices to directly

communicate with each other. Since AHNs are dynamic in nature, they require a dynamic routing

protocol to send the message from one source node to destination. Several approaches have been

proposed for designing multihop routing protocols in wireless AHNs. Flooding is one of them to

discover a dynamic routing path. But Flooding of request packet in the route in wireless AHN

creates a huge amount of traffic which leads to high probability of packet collisions. Also it causes

significant over head in delivering of packet and hence is inappropriate for the dynamic routing. It

also causes more time consumption.

In this paper we propose a efficient multi hop routing algorithm to deliver the message

using the cache variable for intermediate to reduce a large number of path& hence reducing the

traffic generated by normal flooding. We also apply a logic to share the dynamic routing table

between different devices in neighborhood. We also propose a scheme at receiver side to receive

only one valid message from the flooded message and discard all other flooded messages.

I. INTRODUCTION

Wireless Ad-hoc Networks (AHNs) is a set of wireless independent multihop nodes which does not

require any preexisting infrastructure.

This network directly connects one wireless device to another without using any router or hubs.

Instead, each node take part actively in routing by forwarding packet to other nodes, and so the

determination forwarded packet is made dynamically based on the network connectivity.

So, There is no concept of a particular server, any node can be a server or client. It allows all wireless

devices to discover and communicate in peer-to-peer fashion with other who are present within the

range or outside the range (communication is done in multi hop fashion) without involving any central

access points (wireless routers or hubs). Some of the nodes in ad-hoc network may not be able to

communicate directly with each other and dependent on some other nodes to pass their message. Such

networks are often known as multi-hop or store and forward networks. The intermediate node act as

routers, which discover and maintain a table to forward the message to other nodes in the networks.

Ad hoc networks have played an important role in following



1) Military Environment: In case of battlefield adhoc network can be formed by tanks and planes

to communicate with each other.

2) Emergency Operations: In case of rescue working operating in disaster area can form adhoc

network to communicate with each other.

3) Personal Area Networking: Adhoc network can formed by Cell phone, laptop, wrist watch to

form a PAN

4) Education: Used in Virtual classrooms, conferences

Fundamental Protocol in Ad-hoc Networks

Since Wireless Ad-hoc Networks are a new scheme in the field of networking and it is different from

the wired networks. Thus the main issue in AHN is self-organization and wireless transport of

information [4], [5].Since the nodes in a Wireless Ad-hoc Network are mobiles in nature so they are

free to move arbitrarily at any time at any position which results in dynamic and unpredictable

topology. This makes routing process difficult because the topology can be changed any time.

Traditional routing algorithm like link state routing ad distance vector routing is not suitable for adhoc

networking due to the reasons mentioned before. So, proper design of the ad-hoc routing protocol is

needed to overcome the problem. Several protocols have been proposed for routing in ad hoc

networks [3–15, 18-22, 25]. These routing protocols can be classified as basically of following types-

1) Proactive algorithm

2) Reactive algorithm

3) Hybrid algorithm

1) Proactive Algorithm

Proactive algorithm maintains routing tables that contains the lists of destinations and their

corresponding routes .The tables are updated periodically by sharing of tables with the adjacent node.

The disadvantage of this algorithm is that, it requires large amount of data for maintenance and it has

slow response to node failures and change topology.



2) Reactive Algorithm

This type of protocol is also known as on- Demand routing. Here the term on “on demand” means that

the sender node will try to find the route of destination only if it has to send some data. The node will

maintain the route as long as it is needed by it. Therefore, these protocols require less control

overheads. The routing is based on the shortest path algorithm to determine the host.

3) Hybrid (both pro-active and reactive) routing

Hybrid protocol is combination of both reactive protocol and proactive protocol. Here each node first

maintains the routing tables as in case of proactive protocol. The node will also participate in handling

the demand of routing that comes from nodes through reactive protocol.

II. RELATED WORK

Flooding is a method of broadcasting the packets. Here a node first broadcast packet to all its

neighbor nodes .The receiver node will again forward each incoming packet to its neighbor except the

one from which the packet come from, until packet reaches the destination.

Several authors have proposed to use the basic ideas of flooding. A reliable broadcast protocol was

proposed by Pagani [19] for networks that have unpredictable dynamic topology. It gives a routing

algorithm that ranges between flooding and the traditional routing protocols.

A Controlled Flooding protocol was proposed by Lesser and Rom [16]. In this, a message is limited

broadcast on the basis of flooding mechanism ie not throughout the network. Traffic is further limited

by assigning a cost to each link and a wealth to each message. A message is sent on a link on the basis

of priority ie low wealth packet will be sent upon receiving a message; an intermediate node subtracts

the cost of the link from the message wealth.

We propose a multipath routing protocol known as Efficient Multi hop Routing. The protocol is

proactive .It uses the basic features of flooding, but restricts packet propagation by using a cache

variable which store packet id.

It restricts the transmission of duplicate packet having same id that it has received early. Here the

intermediate node will also not transmit packet to those node from which it comes from starting from

the sender. Hence flooding becomes optimized as it uses adaptive mechanisms for restricting flooding

in the network.

III. THE EFFICIENT ROUTING PROTOCOL: OVERVIEW & OUR SCHEME

The traditional algorithm is suitable where rate of topological changes is low but it fails when high.

So when nodes changes its position, the best way is to flood packets in the network [13].so that at

least one packet can be reached.

We proposed an algorithm which is based on optimized flooding .In this scheme we try to deliver

packet to the sender at the most appropriate path .We assume each node to be host and receiver and



each maintains a routing table to route the packet The Bluetooth address is used to uniquely identify

each node in the networks .In the routing table for every entry of node, there is list of nodes from

which a particular node can reach the sender who wishes to send message first check whether the

destination exits in its coverage area or not if exist then it will send the packet directly to it ,otherwise

it finds the list of adjacent nodes from which the destination can be reached and broadcast the

message to all of them. Here the contains are id, destination name and the routing path .At the

intermediate node , it first check whether its cache contains the packet id or not if contains then it

simply discard otherwise it will first find all the list of nodes to which destination can be reached and

broadcast all of them except the nodes which are already in the routing path of packet ,secondly it will

store the packet id to its cache so that any In future if it receives any packet with the same id it will

discard it. This process continues until the message is delivered to its destination. The receiver

received the packet and sends the acknowledged directly to the path from which the packet is

received. We assume that each nodes have a routing table which can be updated dynamically, initially

when a node starts it first search for neighbor and add them to its routing table .After that it will

broadcast its table to its neighbor. On receiving the broadcast message it neighbor will updates their

table as given by the flowing example

Diagram of table 1

Now suppose that two new nodes D,E are introduced into the network on which node D is in the

range of pre-existing network, and E is out of range .Now both device start searching the device and

D found C and E found only they make entry in their table.

Diagram 2

Now both start sharing the table. After that the table will be shown in the following diagram

Diagram 3

Now after a fixed time interval each node will again search for devices and search their table to their

neighbor this will lead to dynamic entry in each routing table of nodes.

Packet format

Each node in the ad hoc network communicates with each other by exchange of the message.

The message consist of two parts the header portion and the body portion

The format of message is shown below

Header Body



Message-

id

Type Destination path Hop

Count

Message-id = this id is generated at the sender side to identify each packet uniquely.

Destination = Bluetooth address of the destination node

Path= this contains the routing path through which packet is coming the last node in the path will be

the sender

Hop Count =Contains the maximum number of hop the packet can travel it si used to avoid

Type: This define the type of message sent

Type 1: indicates the message contains sharing routing table

Type 2: indicate the normal message

Example

Header Body

1559 1 D A,S,E 10

We have path A-S-E, this means that message comes from E, the sender via S-A to receiver D

With type 1 i.e. it contains the share routing table of E also it has unique id 1559

Following format

Node Address

XX Add_1

YY Add _2,Add_1,Add_3

ZZ Add _3,Add_2



Now suppose the sender S wants to send message to D it finds that it can go from D via A and B

having A has highest priority.

IV. ALGORITHM

Routing in the Bluetooth Ad-hoc network is based on limited flooding. In this type of routing the

sender first checks the entries in the routing table the message to all the adjacent node from which it

has to send the message .The intermediate node will accept the message IF it is the destination of the

message otherwise it will flood the message to all the adjacent node from which destination can be

reached except to those nodes from which the message has been reached to it. The intermediate node

also note down the messageID in its cache so that IF in future any message comes with that particular

id could be neglected

Sender Side

Suppose sender S wants to send the message to D

Step 1: find the list of addresses based on hop count which D can be reached in the routing table

Step 2: three cases arises

Case1: Single entry i.e. it can be reached only directly, in this case the following event occurs

a) Send the message to D

b) SET COUNTER =3

c) DO WHILE COUNTER !=0

d) wait for acknowledge received till timeout

e) IF acknowledge received, Terminate process

ELSE resend (message,D)

COUNTER--;

ENDIF ENDLOOP

f) Remove D from the routing table as it is not reachable and print message destination not

reachable

Case 2) Entries are all indirect then

Step2) sendAll (urlList)

Step 3) Wait for the acknowledgement



Step 4 IF receive acknowledge then

Terminates the process

ELSE

Remove the entry in the table for D

Case 4)Entries contain both direct and indirect path then it

Step 1: first try to send directly i.e. send(message,D) and wait for acknowledge

Step 2: IF acknowledge received within Timeout then

Terminate the process

ELSE

Flood the message to all possible multi hop path i.e.send All(message)& wait for

acknowledgment

IF any acknowledge received within time out then

Terminate process ELSE

Print msgdestination Unreachable & Remove that Entry from the table

END IF ENDIF

Receiver side: suppose node S want to send the Message to D vi A-B.

When the packet is received at the node can be of three types.

Case 1: node is the destination

Step 1:the node will simply Accept the message. And extract the body message & use it.

Step2: Send the acknowledge to source through the path in the header portion through which the

message has come.

Receiving Process

IF header type is equal to `1 then IF localcacheconatins message ID then

discard message return ok

ELSE process(message, sender)

add the message id to cache return ok



ELSE IF destination equals the receiver then IF

local cache contains message ID then discard message

return ok ELSE

print “message received ” add the message id to cache

return ok ENDIF

ELSE redirect(message, header)

ENDIF

ENDIF

Process (message, header) Suppose a node A maintains its table as follows

Node List

B B,C

C C

D D

Now entry for B means that it can be reach from C or directly

Now suppose routing table comes from C in the following form

Node List

A A

D C

E E

F F

B B,E,F

At the receiver side it first check whether an entry exist for the coming sender or not if not found i.e.

the case when the sender node starts after completion of search of node of receiving node then it first

search for the device and make entry in the table and process as follows



1) Search for each entry in the incoming table with the existing table except entry for node which

receives the table.

2) IF matches found then

i) Check the corresponding list entry in the existing table against each entry in list of sender node in

the existing table.

ii) IF no entry found then a) add the entry to the list

iii) Else add entry for the node, list in the table

3) End

For example for Node D entry in the table is

D D

The incoming entry for D is

D C

As the previous list entry for D does not contains entry for C there for list is added so it becomes

D D,C

Similarly entry for E, F is not present in the A table so they will be added

But in case of B there is already entry of C in the existing table

B B,C

C C

D D,C

E C

F C

It may also possible that there can be more that there would be more than one more than on entry for

the sender in the existing table

Redirect (message, header)



Step 1: add the local address (i.e. node which is redirecting) to the beginning of the path field in the

header

Step2: find the list for the destination of the packet to be redirected

Step 3: send the packet to all the nodes form where the destination to be reached

Step 4: wait for acknowledgement

Step 5: if ack not received within time then return OK to the sender; Else return failed to sender

Step 6: END

V. PROTOCOL APPLICABILITY AND ASSUMPTIONS

The main assumptions underlying the proposed protocols are

1) Each node first discover the nodes in the neighbor zone during startup

2) Each nodes periodically shares its routing table with each other

3) If a node discover that on for its neighbor is no longer in its zone then it will updated its table and

also informed its neighbor nodes.

4) We assume that the intermediate node has sufficient memory to relay the incoming message

To be transmitted

VI. CONCLUSION

Our algorithm solved the problem of multihop adhoc network which optimized the routing and

reduces a large number of path generated by flooding. Also each node will first prefer to send directly

to node instead of broadcast the packet to all its neighbour .this will greatly reduce the overall traffic

generated by flooding of packet.

REFERENCES

[1] Y. Azar, J. Naor, R. Rom. Routing Strategies in Fast Networks IEEE Transactions On Computers,

45(2):165-173, 1996.

[16] O. Lesser, R. Rom. Routing by controlled flooding in communication networks in proceeding of

IEEE INFOCOM’90,(San Francisco, CA), pp. 910–917, June 1990.

[19] E. Pagani and G.P. Rossi. Reliable broadcast in mobile multi-hop packet networks. Proceedings

of the third annual ACM/IEEE International Conference on mobile computing and networking

(MOBICOM’97), pp. 34–42, 1997.

[4] M. Satyanarayanan. Fundamental challenges in mobile computing. Submitted paper.

[5] M. Haardt W. Mohr R. Becher, M. Dillinger. Broadband wireless access and futurecommunication

networks. Proceedings of the IEEE, 89(1), 2001.

[3] S. Basagni, I. Chlamtac, V.R. Syrotiuk and B.A. Woodward. A Distance Routing



Effect Algorithm for Mobility (DREAM), Proceedings of the fourth Annual mobile

computing and networking, October 1998.

[15] P. Krishna, M. Chatterjee, N.H. Vaidya and D.K. Pradhan. A Cluster-based Approach for

Routing in Ad hoc Networks. In proceedings of Second USENIX Symposium on mobile and Location

Independent Computing, pp. 1–10, January 1996.

[18] S. Murthy and J.J. Garcia–Luna–Aceves. An Efficient Routing Protocol for Wire-Less Networks.

ACM Mobile Networks and Applications, Special Issue on Routing in Mobile Communication

Networks, 1(1):183–197, October 1996.

[22] C.E. Perkins. Ad hoc on-demand distance vector routing, Internet Draft, Internet Engineering

Task Force, work in progress, December 1997.

[25] C.-H. Toh. A novel distributed routing protocol to support ad-hoc mobile computing, Proceeding

of 15th IEEE Annual International Phoenix Conference on Computer Communications, pp. 480–486,

1996.



WORKING MODEL OF WATER JET CUTTING SYSTEM ON LOW PRESSURE

J. N. Mehta1, R. Wadgaokar2, A. Khatal3, M. Chavan4 Mechanical Department, MCT’s Rajiv Gandhi Institute of Technology,

Mumbai, India 1 [email protected]

Abstract

Cutting of raw materials is one of the most common functions in industries. With the advent of

globalization and tough competition from multinational companies, it becomes very essential for

production houses to reduce/eliminate wastes due to inefficient cutting methods. Every cutting

method is based on the input of energy into the material, in order to overcome the chemical bindings

present in the structure of the material. Thermal cutting methods, for example, utilize the energy of

chemical reactions, electricity, or light to produce high temperatures in order to melt the material at

the cutting kerfs. Mechanical methods utilize the kinetic energy of the moving tool or form ductile

materials through the application of pressure. However, these methods causes distortion of material in

the heat affected zone.

In Water-jet Cutting, the energy of the rapidly moving jet is utilized either in the form of a pure

water-jet or abrasive water-jet and then applied to the work piece causing micro-erosion. The cutting

water works as a cooling agent of cutting edge, thus allowing for a very high quality cut without

producing heat affected zone.

Keywords: cutting, micro-erosion, heat-affected zone.

I. INTRODUCTION TO THE PRJECT

This paper is the outcome of the project accomplished in partial fulfillment of final year engineering

project-making. The aim of the paper is to demonstrate the concept of water-jet cutting systems and

empower the research activities and cost-reduction methods to promote the use of the same in India.

A water jet cutter, also known as a water jet, is a tool capable of slicing into metal or other materials (such

as granite) using a jet of water at high velocity and pressure. Its most significant attribute as an accurate

cold cutting process allows it to cut metals without leaving a heat affected zone.



The system uses a jet of pure water at high velocity and pressure. or a mixture of water and an abrasive

substance. The process is essentially the same as water erosion found in nature but greatly accelerated and

concentrated.

There are basically two types of water-jet cutters:

a) Pure Water-Jet Cutter

b) Abrasive Water-Jet Cutter

As a part of our project, we have successfully developed a working model of pure water-jet cutting

system. The system utilizes a pump of capacity 2000 psi and 140 bar pressure as compared to 60,000 psi

and 4000 bar pressure in present industrial use. Such pressure pumps are usually used in garages for car

washing. In actual cutting systems, the pressure is intensified by double acting intensifier, whereas we

have obtained the intensification with the help of piston movements as shown in fig(2).

Fig.1. Actual Intensifier

Fig.2.Intensification by Piston Action



Fig.3. Water storage tank (2000 litres) Fig.4.Water Purifier

Fig.5.Sand Feeder

II. INDUSTRIAL STUDY

An observatory study was made at one of the Waterjet Cutting Services Factory on the following

Machine:

WATERJET GERMANY M/C

Abrasive Waterjet

MODEL NO:S3015

BED SIZE: 3000mm x 1500 mm

Pressure Range: 3600-4000bar

Sand FeedRate :400-800 gm/min

Material not cut-Toughened Glass

The following figure shows the different components of the Water-jet Cutting System.



Fig 6 PLC System

Fig.7.Waterhead Cutting a material

III. DESIGNS/DRAWINGS:



Water Jet Cutting Systems utilize the ‘intensification principle.’ In industrial units, water is pressurized

to a pressure of approximately 200 bar. A plunger with a face area of 20 times less than the passage

pushes against the water. Therefore, the 200 barpressure is ‘intensified’ twenty times, yielding

The ‘intensification principle’ increases the pressure according to the following Pascal’s Law

equation.

PRESSURE = FORCE /AREA

We have selected SS-316 as raw material for nozzle and nut, for its strength and resistance to water

corrosion. The software used is Pro-E wildfire 4.0 . To obtain considerable velocity of water-jet at outlet,

we obtained an orifice of 1 mm diameter. Water would flow through it after passing through the nozzle of

3mm diameter. The outer diameter is 21 mm to provide considerable wall thickness to sustain such high

pressures. The designs and stress-stain analysis are shown in the given figures.

Fig.8.Nozzle Design



Fig.9.Nut Design

Fig 10 Office Design



Fig.11. Assembly of cutting head

Fig.12.Stress-Strain Analysis for nozzle



Difficulties that were involved

1. The initial problem was to get a through-hole drilled in 150 mm long SS rod, which is not possible

with conventional drilling methods.

2. The other problem was to obtain a considerable pressure to cut through thin materials like foam,

rubber, etc.

How the Difficulties were overcome

1. Drilling was done with the help of EDM at a die-making factory.

2. Garage pumps were found to give required pressure and discharge through a small orifice.

IV. PROJECT DEMO The following figures are snapshots of demo carried out in college. Further, the observation table has been prepared which gives an indication of cutting speed to be used for different materials.

Fig.13.Actual Cutting Head Fig.14.Orifice of 1mm diameter

Fig.15.High Velocity Water jet Fig.16.Cutting through a brick



Fig.17.Cutting P.O.P. Block Fig.18.Cutting Foam

V. PROJECT OBSERVATIONS: Pump Specifications: 140 bar 2000psi Orifice size: zero degree, 1mm Lpm:11 Power requirement:Single phase, 4 HP

Table 1

Sr. No MATERIAL THICKNESS (mm)

CUTTING SPEED (mm/min)

1 P.O.P. 2 59.1

2 TYRE 2 3008.78

3 FOAM 12 5179.89

Table 2

SR.NO MATERIAL THICKNESS (mm)

CUTTING SPEED (mm/min)

1 RUBBER 2 27000

10 11500 20 2200

2 SYNTHETIC MATERIAL

2 22500 5 8900

10 3400

3 FOAMED MATERIAL

10 27500 100 5500



Table1 and Table 2 gives the obsevations of our project as well as industrial standards, We observe that

the readings are almost consistent with these standards, taking into consideration the pressure difference.

VI. FUTURE PLANS

We plan to automate our project using steeper motors to give it controlled motion, restricted to a plane in

x-y direction.

VII. APPLICATIONS OF WATERJET CUTTING

• Pure waterjet is used mainly for relatively soft materials such as plastic, textiles, paper, sealing

materials, metalic foils, plywood, composites, leather, etc.

• The abrasive application is used for harder materials: Metals, Glass, Stone, Concrete, Glass

composites, Ceramics and hard materials like Aluminum oxide or Silicone Oxide.

• The only material that cannot be cut is Toughened Glass.

• It is widely used in preparations of inlays for floorings and furniture.

It is the preferred method when the materials being cut are sensitive to high temperatures.

VIII. ADVANTAGES OF WATERJET CUTTING

Environmentally friendly

Can cut complicate shapes

Better material utilization

Cutting in all axes

High speeds for various materials

Easily adaptable to automatic contouring

Easy programming with standard CAD/CAM systems

Only simple fixtures required

No heat affected zones

Stress free cutting

No material jump-off

No tool sharpening

No dust, fumes, or gases released

IX. CONCLUSION

WATER JET does not create a burr or HAZ as the heat cutting processes do. This saves expenses

for secondary operations.

WATER JET is slower than heat cutting techniques in nonconductive materials and similar for

conductive materials like aluminum.



WATER JET has almost unlimited thickness capability whereas high powered plasma is limited

to about 2” and laser to about 0.75” thick.

REFERENCES:

1. R.K.Rajput, “Fluid Mechanics and Hydraulic Machines, Part-2”, by S.Chand Publication,

ISBN:81-219-1668-2, pp.1286-1287.

2. M.K. Jackson and T.W. Davies, “Conclusions, Nozzle Design For Coherent Water Jet

Production”, Proceedings of the Second U.S. Water Jet Conference, May 24-26, 1983, pp.73

3. Flow International Corporation, “Waterjet White Paper”, Waterjet Seminar, pp.24.

4. Water Jet Cutting- A Technology on the Rise (2010)1-12 e-book:www.kmtwaterjet.com/

5. Abrasive water jet Machining -Chuck Gallant (2009) e-book: www.waterjets.org/

6. Water jet Cutting-Application and Capability (2004):www.waterjetparts.com/



STEGANOGRAPHY Arihant Gaggar, Kapil Manek, Nachiket Jain

Thakur College of Engineering, Kandivali, Mumabi, India [email protected]

Abstract

Steganography is the art of hiding the information within the carrier file such as image, audio, etc.

in such a way that the carrier would appear as an ordinary file to the intruders.Steganography is

the writing hidden messages in such a way that no one apart from the sender and intended

recipient even realizes that there is a hidden message. By contrast, cryptography obscures the

meaning of a message, but it does not conceal the fact that there is a message.

I. INTRODUCTION

Today, the term steganography includes the concealment of digital information within computer files.

For example, the sender might start with an ordinary-looking image file, then adjust the color of every

100th pixel to correspond to a letter in the alphabet—a change so subtle that someone who isn't

actively looking for it is unlikely to notice it.

Steganalysis is the detection of the hidden information present in a carrier. It is the art of discovering

and rendering useless such covert messages. Steganalysis can be divided into two parts: Passive and

Active.

Passive Steganalysis involves only detection of the presence of hidden information or a modified

carrier whileActive Steganalysis involves extracting the hidden information as well. Our system

works on Passive steganalysis.

Steganalysis techniques produce some discernible change in the file size, statistics or both. These

changes can manifest themselves in color variations, loss of resolution and other distortions that are

visible to the human eye.

The purpose of this project is to implement the tool which will embed a secret message (which might

be a copyright mark, or a covert communication, or a serial number) in a cover message (such as an

audio recording, or digital images, or the video files, etc) and provide the highly private and secure

data transfer without third party intervention.Applications of steganography include protection against

detection (data hiding) & protection against removal that seem to hold promise for copyright

protection, tracing source of illegal copies, etc.

II. STEGANOGRAPHY BASICS

Steganography literally means covered writing. Steganography simply takes one piece of information

and hides it within another file like images contain unused or insignificant areas of data.

Steganography certainly has beneficial advantages. It is an effective tool for protecting personal



information. Steganography has its place in the security. On its own, it won’t serve much but when

used as a layer of cryptography; it would lead to a greater security.

Detection of covert communications that utilize images has become an important issue. So we are

providing steganography using image, documents and audio as media, including security.

III. HISTORY OF STEGANOGRAPHY

Hidden messages on messenger's body: also in ancient Greece. Herodotus tells the story of a message

tattooed on a slave's shaved head, hidden by the growth of his hair, and exposed by shaving his head

again.

In the 20th century, invisible inks where a widely used technique. In the Second World War, people

used milk, vinegar, fruit juices and urine to write secret messages. When Heated, these fluids become

darker and the message could be read.

Giovanni Batista Porta described how to conceal a message within a hard boiled egg by writing on the

shell with a special ink made with an ounce of alum and a pint of vinegar. The solution penetrates the

porous shell, leaving no visible trace, but the message is stained on the surface of the hardened egg

albumen, so it can be read when the shell is removed.

The first recorded uses of steganography can be traced back to 440 BC when Herodotus mentions two

examples of steganography in The Histories of Herodotus. Demaratus sent a warning about a

forthcoming attack to Greece by writing it directly on the wooden backing of a wax tablet before

applying its beeswax surface. Wax tablets were in common use then as reusable writing surfaces,

sometimes used for shorthand. Another ancient example is that of Histiaeus, who shaved the head of

his most trusted slave and tattooed a message on it. After his hair had grown the message was hidden.

The purpose was to instigate a revolt against the Persians

IV. STEGANOGRAPHIC SYSTEM

Fig 1

Modular Description

Message File: The data to be concealed.

Cover File: The file which will be used to hide the message (also called a carrier or a

container.

Secret Key: The Secret Key with the help of which the hidden message in a cover signal can

be extracted at the receiving side. It is used as secured key.

Steganography Tool: This module is to embed the message one wants to hide within the

carrier using a steganographic technique which give Stego-file as output.

Stego-file: The Stego-file is output of the System at sender end and input at the receiver end.

Communication Channel: The Communication Channel is any transmission medium.



Fig 1

V. STEGANOGRAPHIC TECHNIQUES

A. Physical steganography

Steganography has been widely used, including in recent historical times and the present day.

Possible permutations are endless and known examples include:

Hidden messages within wax tablets — in ancient Greece, people wrote messages on the wood,

then covered it with wax upon which an innocent covering message was written



• Hidden messages on messenger's body — also used in ancient Greece. Herodotus tells the story of

a message tattooed on a slave's shaved head, hidden by the growth of his hair, and exposed by

shaving his head again. The message allegedly carried a warning to Greece about Persian invasion

plans. This method has obvious drawbacks, such as delayed transmission while waiting for the

slave's hair to grow, and the restrictions on the number and size of messages that can be encoded

on one person's scalp.

• During World War II, the French Resistance sent some messages written on the backs of couriers

using invisible ink.

• Hidden messages on paper written in secret inks, under other messages or on the blank parts of

other messages.

• Messages written in Morse code on knitting yarn and then knitted into a piece of clothing worn by

a courier.

• Messages written on envelopes in the area covered by postage stamps.

• During and after World War II, espionage agents used photographically produced microdots to

send information back and forth. Microdots were typically minute, approximately less than the

size of the period produced by a typewriter. World War II microdots needed to be embedded in

the paper and covered with an adhesive, such as collodion. This was reflective and thus detectable

by viewing against glancing light. Alternative techniques included inserting microdots into slits

cut into the edge of post cards.

• During World War II, a spy for Japan in New York City, Velvalee Dickinson, sent information to

accommodation addresses in neutral South America. She was a dealer in dolls, and her letters

discussed how many of this or that doll to ship. The stegotext was the doll orders, while the

concealed "plaintext" was itself encoded and gave information about ship movements, etc. Her

case became somewhat famous and she became known as the Doll Woman.

Cold War counter-propaganda. In 1968, crew members of the USS Pueblo intelligence ship held as

prisoners by North Korea, communicated in sign language during staged photo opportunities,

informing the United States they were not defectors, but rather were being held captive by the North

Koreans. An example of above explanation is given below:

Example



Within this picture, the letter positions of a hidden message are represented by increasing numbers (1

to 20), and a letter value is given by its intersection position in the grid. For instance, the first letter of

the hidden message is at the intersection of 1 and 4. So, after a few tries, the first letter of the message

seems to be the 14th letter of the alphabet; the last one (number 20) is the 5th letter of the alphabet.

B. Digital Steganography

Modern steganography entered the world in 1985 with the advent of the personal computer being

applied to classical steganography problems. Development following that was slow, but has since

taken off, going by the number of "stego" programs available: Over 800 digital steganography

applications have been identified by the Steganography Analysis and ResearchCenter. Digital

steganography techniques include:

• Concealing messages within the lowest bits of noisy images or sound files.

• Concealing data within encrypted data or within random data. The data to be concealed is first

encrypted before being used to overwrite part of a much larger block of encrypted data or a

block of random data (an unbreakable cipher like the one-time pad generates ciphertexts that

look perfectly random if you don't have the private key).

• Concealed messages in tampered executable files, exploiting redundancy in the targeted

instruction set.

• Pictures embedded in video material (optionally played at slower or faster speed).

• Changing the order of elements in a set.

• Content-Aware Steganography hides information in the semantics a human user assigns to a

datagram. These systems offer security against a non-human adversary/warden.

• Blog-Steganography. Messages are fractionalized and the (encrypted) pieces are added as

comments of orphaned web-logs (or pin boards on social network platforms). In this case the

selection of blogs is the symmetric key that sender and recipient are using; the carrier of the

hidden message is the whole blogosphere.

• Modifying the echo of a sound file (Echo Steganography)

Example:



Image of a tree. Removing all but the two least significant bits of each color component produces an

almost completely black image. Making that image 85 times brighter produces the image below.

C. Printed Steganography

Digital steganography output may be in the form of printed documents. A message, the plaintext, may

be first encrypted by traditional means, producing a ciphertext. Then, an innocuous covertext is

modified in some way so as to contain the ciphertext, resulting in the stegotext. For example, the letter

size, spacing, typeface, or other characteristics of a covertext can be manipulated to carry the hidden

message. Only a recipient who knows the technique used can recover the message and then decrypt it.

Francis Bacon developed Bacon's cipher as such a technique.

VI. APPLICATIONS

• Usage in modern printers

Steganography is used by some modern printers, including HP and Xerox brand color laser printers.

Tiny yellow dots are added to each page. The dots are barely visible and contain encoded printer serial

numbers, as well as date and time stamps.

• Alleged use by terrorists

When one considers that messages could be encrypted steganographically in e-mail messages,

particularly e-mail spam, the notion of junk e-mail takes on a whole new light. Coupled with the

"chaffing and winnowing" technique, a sender could get messages out and cover their tracks all at

once.

Despite this, there are no known instances of terrorists using computer steganography. Al Qaeda's

use of steganography is somewhat simpler: In 2008 a British man, Rangzieb Ahmed, was alleged to

have a contact book with Al-Qaeda telephone numbers, written in invisible ink. He was convicted of

terrorism.

• Alleged use by intelligence services



In 2010, the Federal Bureau of Investigation revealed that the Russian foreign intelligence service

uses customized steganography software for embedding encrypted text messages inside image files

for certain communications with "illegal agents" (agents under non-diplomatic cover) stationed

abroad.

VII. CONCLUSION

Thus we would like to conclude that stegonagraphy is like a two edged sword. Its applicationsrange

from all the frontiers for intelligence services and also do aid the likes of the infamous terrorist.

Stegonagraphy is an emerging trend in the field of data security and encryption.The advantage of

steganography, over cryptography alone, is that messages do not attract attention to themselves.

Plainly visible encrypted messages—no matter how unbreakable—will arouse suspicion, and may in

themselves be incriminating in countries where encryption is illegal. Therefore, whereas cryptography

protects the contents of a message, steganography can be said to protect both messages and

communicating parties.

REFERENCE

1. Wayner, Peter (2002). Disappearing cryptography: information hiding: steganography &

watermarking (http:/ /

2. www. wayner. org/ node/ 6). Amsterdam: MK/Morgan Kaufmann Publishers. ISBN 1-55860-

769-2.

3. http:/ / www. dmoz. org/ Computers/ Security/ Products_and_Tools/ Cryptography/

Steganography/

4. Information Hiding: Steganography & Digital Watermarking. http:/ / www. jjtc. com/

Steganography

5. http://www.wikipedia.org/stegonagraphy/

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