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BUSI 240Introduction to Information Systems
Tuesday & Thursday 8:05am – 9:30am
Wyant Lecture Hall
Please initial the roster on the back table.
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Current Events – What’s going on?
Schwartz On Security: Slouching Toward Smartphone, Apple Armageddon Every new year brings fresh warnings that the next smartphone botnet or Apple "I Love You" virus is imminent, while real attacks keep escalating.
Smartphones and Apple OS X computers currently draw little attention from attackers.
Could all that be about to change, as the pace of patches and improvements in software design make Windows a less juicy target? We've been hearing this refrain for at least a couple of years, and I'm still not convinced. http://www.informationweek.com/news/security/vulnerabilities/showArticle.jhtml?articleID=229100291
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Holocaust historical data goes digitalThe world's largest collection of Holocaust documents is going digital.
Israel's Holocaust memorial, Yad Vashem, is teaming up with Google to make its photographs and documents interactive and searchable on the Internet.
The project launched Wednesday with a collection of 130,000 photos that can now be searched directly from Google, using standard keywords and other data that make it far easier than in the past to find the desired information.http://news.yahoo.com/s/ap/20110126/ap_on_hi_te/ml_israel_holocaust_google
Current Events – What’s going on?
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Its wireless sensors help users run some programs with their thoughts
What if you could simply think about an action, and the computer would respond?http://www.businessweek.com/magazine/content/08_32/b4095000909813.htm
Current Events – What’s going on?
Emotiv's New Mind-Control Headset for PCs
Automated Theft Machines
One April evening in 2009, a Gray Nissan truck idled in a parking lot across from a Wachovia Bank in a Fort Lauderdale, Fla., suburb. A man wearing sunglasses and a baseball cap hopped out and walked over to the bank's ATM — but not to withdraw cash, at least not right away. With practiced ease, he quickly glued a magnetic-card reader onto the front of the machine, on top of the ATM's card-reading slot, and swapped out the light panel above it with one containing a tiny video camerahttp://www.time.com/time/magazine/article/0,9171,2041113,00.html#ixzz1CZfZKpEX
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Current Events – What’s going on?
Still patchyAmerican firms are hiring again, but hold the cheers
WITH the dawn of 2011 America’s recovery is officially longer-lived than the recession that preceded it. It is a recovery that seems to be strengthening, raising hopes that employers will at last develop an appetite for hiring. America remains over 7m jobs short of the previous employment peak, and figures published on January 7th showed that the economy added just 103,000 jobs in December—scarcely enough to keep up with population growth. The unemployment rate fell in that month by nearly half a point, to 9.4%, but that was mainly because so many jobless workers gave up and stopped looking. http://www.economist.com/research/articlesBySubject/displaystory.cfm?subjectid=348876&story_id=17906059
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Current Events – What’s going on?
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Current Events – What’s going on?
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Quiz #1
Computer Hardware
History of computersTypes of computer systems
Hardware components and functionsComputer peripherals
Chapter
3b
McGraw-Hill/Irwin Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved.
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Current Events – What’s going on?
IBM unveils world's fastest supercomputerSequoia, built for the US department of energy, is almost 20 times more powerful than the previous record holderhttp://www.guardian.co.uk/technology/2009/feb/03/fastest-supercomputer-ibm-sequoia
IBM Sequoia
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Microcomputer Systems
Personal Computer (PC) – microcomputer for use by an individual
Desktop – fit on an office deskLaptop – small, portable PC
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Recommended features for PC
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Microcomputer Systems
Workstation – a powerful, networked PC for business professionals
Network Server – more powerful microcomputers that coordinate telecommunications and resource sharing in small networks
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How corporate buyers choose PCs
Solid performance at a reasonable priceOperating system readyConnectivity – reliable network interface or
wireless capability
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Terminals
Devices that allow access to a networkDumb terminals – keyboard and video monitor
with limited processingIntelligent terminals – modified networked PCs
or network computersNetwork terminals or computers
Windows terminals depend on network servers for software, processing and storage
Internet terminals depend to the Internet or Intranet for operating systems and software
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Information Appliances
Hand-held microcomputer devicesPersonal digital assistants (PDA)
BlackBerryVideo-game consolesInternet enabled cellular phones
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Midrange systems
High-end network serversMinicomputers for scientific research and
industrial process monitoring Less costly to buy, operate and maintain than
mainframe
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Mainframe Computer Systems
Large, fast powerful computer systemsLarge primary storage capacityHigh transaction processingComplex computations
Can be used as superservers for large companies
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Supercomputer Systems
Extremely powerful systemsScientific, engineering and business
applications at extremely high speedsGlobal weather forecasting, military defenseParallel processing with thousands of
microprocessorsBillions of operations per secondMillions of dollars
Minisupercomputers costing hundreds of thousands of dollars
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Cray 2 Supercomputer
IBM Supercomputer
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Computer hardware functions
InputKeyboards, mice, optical scannersConvert data into electronic form
ProcessingCentral Processing Unit (CPU)
Arithmetic-logic unit performs the arithmetic functions Control unit
OutputVideo display units, printers, etc.Convert electronic information into human-
intelligible form
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Computer hardware functions
StoragePrimary Storage Unit or memorySecondary Storage
Magnetic disks and Optical disksControl
Control unit of the CPUControls the other components of the computer
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Computer Processing Speeds
Millisecond – thousandth of a second
Microsecond – millionth of a second
Nanosecond – billionth of a second
Picosecond – trillionth of a second
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Computer Processing Speeds
MIPS – million instructions per secondTeraflops – trillions of floating point operations
per second (Supercomputer)Clock speed of the computer:
Megahertz (MHz) – millions of cycles per secondGigahertz (GHz) – billions of cycles per second
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Moore’s Law
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Peripherals
Peripheral is generic name for all input, output, and secondary storage devices that are part of the computer system but are not part of the CPU
Online devicesSeparate from CPUBut electronically connected to and controlled by
CPUOffline devices
Separate from and not under control of the CPUPeripherals are online devices
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Peripheral Checklist
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Input technologies
Keyboard: most widely-usedGraphical user interface (GUI)
Icons, menus, windows, buttons, barsUsed for selection
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Pointing Devices
Electronic MouseTrackball – Stationary device like a mouse
Roller ball used to move cursor on screen.Pointing Stick – Small eraser head-like device
in keypadMoves cursor in direction of pressure placed on
stick.
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Pointing Devices
Touchpad – Small rectangular touch-sensitive surface Moves the cursor in the direction of finger moves
on the pad Touch Screen – use computer by touching
screenVideo display screen that emits a grid of infrared
beams, sound waves, or a slight electric current Grid is broken when the screen is touched.
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Pen-based Computing
Used in Tablet PCs and PDAsPressure-sensitive layer like touch screen
under liquid crystal display screen Have software that digitizes handwriting, hand
printing, and hand drawing
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Speech Recognition Systems
Discrete: pause between each wordContinuous: conversationally-paced speech
System compares your speech patterns to library of sound patternsTraining: to recognize your voice patternsSpeaker independent system: understand voice
never heard beforeUsed in voice-messaging computers
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Optical Scanning
Read text or graphics and convert them into digital input
Desktop or flatbed scannersOptical Character Recognition (OCR):
Read characters and codes Used to read merchandise tags, sort mail, score
testsOptical scanning wands
Read bar codes such as the Universal Product Code (UPC)
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Other Input Technologies
Magnetic stripeRead magnetic stripe on credit cards
Smart cardsMicroprocessor chip and memory on credit cardUsed more often in Europe than in US
Digital camerasMagnetic Ink Character Recognition (MICR)
Identification numbers of bank and account printed in magnetic ink on bottom of check
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Output TechnologiesVideo displays
Cathode ray tube (CRT) like a television Most desktop PC screens
Liquid crystal displays (LCDs) Laptop and PDAs, some PCs
Printed Output Inkjet printer
Spray ink on pageLaser printer
Electrostatic process like photocopying machineVoice response systems
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Storage tradeoffs
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Computer Storage Fundamentals
Binary representationData are processed and stored in computer system
through the presence or absence of signalsEither ON or OFF
ON = number 1OFF = number 0
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Bit and Byte
Bit (short for binary digit)Smallest element of dataEither zero or one
ByteGroup of eight bits which operate as a single unitRepresents one character or number
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Representing characters in bytes
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Computers use binary system to calculate
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Measuring storage capacities
Kilobyte (KB): one thousand bytesMegabyte (MB): one million bytesGigabyte (GB): one billion bytesTerabyte (TB): one trillion bytesPetabyte (PB): one quadrillion bytes
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Direct and Sequential Access
Direct Access or Random AccessDirectly store and retrieve dataEach storage position has unique address and
can be accessed in same length of timeSemiconductor memory chips, magnetic disks
Sequential AccessData is stored and retrieved in a sequential
processMust be accessed in sequence by searching
through prior dataMagnetic tape
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Direct and sequential access
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Semiconductor memory
Microelectronic semiconductor memory chipsUsed for primary storageAdvantage:
Small sizeFastShock and temperature resistance
Disadvantage:Volatility: must have uninterrupted electric
power or lose memory
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Silicon wafer
Each of the rectangles on this earlier silicon wafer is a four-megabit RAM chip. The wafer is the structural unit that all chips are fabricated on. The chips are cut out and placed into their individual housings.
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Two types of semiconductor memory
RAM: random access memoryMost widely used primary storage mediumVolatile memoryRead/write memory
ROM: read only memoryPermanent storageCan be read but cannot be overwrittenFrequently used programs burnt into chips during
manufacturingCalled firmware
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Magnetic Disks
Used for secondary storageFast access and high storage capacity
Source: Quantum. Source: Corbis.
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Construction and Operation of the Hard Disk
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A platter from a 5.25" hard disk, with 20 concentric tracks drawn over the surface. Each track is divided into 16 imaginary sectors.
The Difference Between Tracks and Cylinders
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Types of magnetic disks
Floppy disksMagnetic disk inside a plastic jacket
Hard disk drivesMagnetic disk, access arms, and read/write heads in
sealed moduleRAID (Redundant arrays of independent disks)
Disk arrays of interconnected hard disk drivesFault tolerant with multiple copies on several disks
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Flash drive
New type of permanent storage
Uses semiconductor memory
Small chip with thousands of transistors
Easily transportedAlso called jump drives,
USB flash drives
Source: Courtesy of Lexar Media.
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Open casing of 2.5” traditional hard disk drive
(left) and solid-state drive (center).
Solid State Drive
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Current Events – What’s going on?
IBM unveils world's fastest supercomputerSequoia, built for the US department of energy, is almost 20 times more powerful than the previous record holderhttp://www.guardian.co.uk/technology/2009/feb/03/fastest-supercomputer-ibm-sequoia
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Video
http://www.eweek.com/c/a/Desktops-and-Notebooks/Solid-State-Drives-Better-for-Users/
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Pros and Cons of SSDDisadvantages• Price • Capacity • Vulnerability to abrupt power
loss• Limited write cycles• Higher Power Consumption
(overall)
Advantages• Faster startup (read)• Faster access to
data/applications (read)• Constant performance (read)• No Noise• Higher mechanical reliability• Larger range of operating
temperatures• Lower weight and size
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Magnetic Tape
Secondary storageTape reels and cartridgesUsed in robotic automated drive assembliesArchival storage and backup storage
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Tape Library System
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Optical Disks
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Uses of optical disks
Image processingLong term storage of historical files of imagesScan documents and store on optical disks
Publishing medium for fast access to reference materialsCatalogs, directories, etc.
Interactive multimedia applicationsVideo games, educational videos, etc.