MECHANICS BUILDING GENERAL

L | C | LOGISTICS

PLANT MANUFACTURING AND BUILDING FACILITIES EQUIPMENT

Engineering-Book

ENGINEERING FUNDAMENTALS AND HOW IT WORKS

September 2014

Expertise in Process Engineering Optimization Solutions & Industrial Engineering Projects Management 

Supply Chain Manufacturing & DC Facilities Logistics Operations Planning Management

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An audio power amplifier is an electronic amplifier that amplifies low-power audio signals (signals composed primarily of frequencies between 20 - 20 000 Hz, the human range of hearing) to a level suitable for driving loudspeakers

It is the final electronic stage in a typical audio playback chain

The preceding stages in such a chain are low power audio amplifiers which perform tasks like pre-amplification (this is particularly associated with record turntable signals), equalization, tone controls, mixing/effects, or audio sources like record players, CD players, and cassette players

Most audio power amplifiers require these low-level inputs to adhere to line levels

While the input signal to an audio power amplifier may measure only a few hundred microwatts, its output may be tens or hundreds of watts for a home system or thousands or tens of thousands of watts for a concert sound reinforcement system

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Key design parameters for audio power amplifiers are frequency response, gain, noise, and distortion

These are interdependent; increasing gain often leads to undesirable increases in noise and distortion

While negative feedback actually reduces the gain, it also reduces distortion

Most audio amplifiers are linear amplifiers operating in class AB

Since modern digital devices, including CD and DVD players, radio receivers and tape decks already provide a "flat" signal at line level, the preamp is not needed other than as a volume control and source selector

One alternative to a separate preamp is to simply use passive volume and switching controls, sometimes integrated into a power amplifier to form an integrated amplifier

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Radio is the radiation (wireless transmission) of electromagnetic signals through the space

Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width

When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor

The information in the waves can be extracted and transformed back into its original form

Amplitude modulation of a carrier wave works by varying the strength of the transmitted signal in proportion to the information being sent

For example, changes in the signal strength can be used to reflect the sounds to be reproduced by a speaker, or to specify the light intensity of television pixels

It was the method used for the first audio radio transmissions, and remains in use today; "AM" is often used to refer to the medium wave broadcast band

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Frequency modulation varies the frequency of the carrier

The instantaneous frequency of the carrier is directly proportional to the instantaneous value of the input signal

Digital data can be sent by shifting the carrier's frequency among a set of discrete values, a technique known as frequency-shift keying

FM is commonly used at VHF radio frequencies for high-fidelity broadcasts of music and speech (see FM broadcasting)

Normal (analog) TV sound is also broadcast using FM

Angle modulation alters the instantaneous phase of the carrier wave to transmit a signal

It is another term for phase modulation

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The electromagnetic wave is intercepted by a tuned receiving antenna; this structure captures some of the energy of the wave and returns it to the form of oscillating electrical currents

At the receiver, these currents are demodulated, which is conversion to a usable signal form by a detector sub-system

The receiver is "tuned" to respond preferentially to the desired signals, and reject undesired signals

Early radio systems relied entirely on the energy collected by an antenna to produce signals for the operator

Radio became more useful after the invention of electronic devices such as the vacuum tube and later the transistor, which made it possible to amplify weak signals

Today radio systems are used for applications from walkie-talkie children's toys to the control of space vehicles, as well as for broadcasting, and many other applications

A crystal receiver, consisting of an antenna, rheostat, electromagnetic coil, crystal rectifier, capacitor, headphones and ground connection

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Wireless communication is the transfer of information between two or more points that are not connected by an electrical conductor

The most common wireless technologies use radio

With radio waves distances can be short, such as a few meters for television or as far as thousands or even millions of kilometers for deep-space radio communications

Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones

Somewhat less common methods of achieving wireless communications includes the use of other electromagnetic wireless technologies, such as light, magnetic, or electric fields or the use of sound

It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking

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Light, colors, AM and FM radio, and electronic devices make use of the electromagnetic spectrum. The frequencies of the radio spectrum that are available for use for communication are treated as a public resource

This determines which frequency ranges can be used for what purpose and by whom

Wireless communication spans the spectrum from 9 kHz to 300 GHz.

Light comparison

Name Wavelength Frequency (Hz) Photon energy (eV)

Gamma ray less than 0.01 nm more than 10 EHz 100 keV - 300+ GeV

X-Ray 0.01 to 10 nm 30 PHz - 30 EHz 120 eV to 120 keV

Ultraviolet 10 nm - 400 nm 30 EHz - 790 THz 3 eV to 124 eV

Visible 390 nm - 750 nm 790 THz - 405 THz 1.7 eV - 3.3 eV

Infrared 750 nm - 1 mm 405 THz - 300 GHz 1.24 meV - 1.7 eV

Microwave 1 mm - 33 centimeters 300 GHz - 1000 MHz 1.24 meV - 3.3 µeV

Radio 1 mm - km 300 GHz - 3 kHz 1.24 meV - 12.4 feV

Radio frequency

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The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite (TCP/IP) to link several billion devices worldwide

It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless, and optical networking technologies

The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), the infrastructure to support email, and peer-to-peer networks for file sharing and telephony

As user data is processed through the protocol stack, each abstraction layer adds encapsulation information at the sending host

Data is transmitted over the wire at the link level between hosts and routers

Encapsulation is removed by the receiving host

Intermediate relays update link encapsulation at each hop, and inspect the IP layer for routing purposes

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Internet service providers connect customers, which represent the bottom of the routing hierarchy, to customers of other ISPs via other higher or same-tier networks

At the top of the routing hierarchy are the tier 1 networks, large telecommunication companies that exchange traffic directly with each other via peering agreements

Tier 2 and lower level networks buy Internet transit from other providers to reach at least some parties on the global Internet, though they may also engage in peering

An ISP may use a single upstream provider for connectivity, or implement multi homing to achieve redundancy and load balancing

Internet exchange points are major traffic exchanges with physical connections to multiple ISPs

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End-nodes typically use a default route that points toward an ISP providing transit, while ISP routers use the Border Gateway Protocol to establish the most efficient routing across the complex connections of the global Internet

Large organizations, such as academic institutions, large enterprises, and governments, may perform the same function as ISPs, engaging in peering and purchasing transit on behalf of their internal networks

Research networks tend to interconnect with large sub networks such as GEANT, GLORIAD, Internet2, and the UK's national research and education network, JANET

Computers and routers use a routing table in their operating system to direct IP packets to the next-hop router or destination

Routing tables are maintained by manual configuration or automatically by routing protocols

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An air ionizer (or negative ion generator) is a device that uses high voltage to ionize (electrically charge) air molecules

Negative ions, or anions, are particles with one or more extra electrons, conferring a net negative charge to the particle

Cations are positive ions missing one or more electrons, resulting in a net positive charge

Most commercial air purifiers are designed to generate negative ions

Air ionizers are used in air purifiers

Airborne particles are attracted to the electrode in an effect similar to static electricity

These ions are de-ionized by seeking earthed conductors, such as walls and ceilings

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Ground (electricity) In electrical engineering, ground or earth can refer to the reference point in an electrical circuit from which voltages are measured, a common return path for electric current, or a direct physical connection to the Earth

In mains powered equipment, exposed metal parts are connected to ground to prevent user contact with dangerous voltage if electrical insulation fails

Connections to ground limit the build-up of static electricity when handling flammable products or electrostatic-sensitive devices

A static electric charge is created whenever two surfaces contact and separate, and at least one of the surfaces has a high resistance to electrical current (and is therefore an electrical insulator)

The effects of static electricity are familiar to most people because people can feel, hear, and even see the spark as the excess charge is neutralized when brought close to a large electrical conductor (for example, a path to ground), or a region with an excess charge of the opposite polarity (positive or negative)

The familiar phenomenon of a static shock–more specifically, an electrostatic discharge–is caused by the neutralization of charge.

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Removing or preventing a buildup of static charge can be as simple as opening a window or using a humidifier to increase the moisture content of the air, making the atmosphere more conductive. Air ionizers can perform the same task

A dehumidifier is generally a household appliance which reduces the level of humidity in the air, usually for health or comfort reasons, or to eliminate musty odor. Excessively humid air can cause mold and mildew to grow inside homes, both of which pose numerous health risks

By their operation, dehumidifiers extract water from the conditioned air

This collected water (usually called condensate) cannot be used for drinking, so it must be discarded

Some designs, such as the ionic membrane dehumidifier, dispose of excess water in a vapor rather than liquid form

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High-efficiency particulate air or HEPA[ is an air filter

Filters meeting the HEPA standard have many applications, including use in medical facilities, automobiles, aircraft and homes

The filter must satisfy certain standards of efficiency such as those set by the United States Department of Energy

To qualify as HEPA by US government standards, an air filter must remove (from the air that passes through) 99.97% of 0.3 µm particles

HEPA filters are composed of a mat of randomly arranged fibres

The fibres are typically composed of fiberglass and possess diameters between 0.5 and 2.0 micrometers

Key factors affecting function are fiber diameter, filter thickness, and face velocity

The air space between HEPA filter fibres is much greater than 0.3 μm.

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a clean room has a controlled level of contamination that is specified by the number of particles per cubic meter at a specified particle size

To give perspective, the ambient air outside in a typical urban environment contains 35,000,000 particles per cubic meter in the size range 0.5 μm and larger in diameter

Clean rooms are not sterile (i.e., free of uncontrolled microbes); only airborne particles are controlled

Particle levels are usually tested using a particle counter and microorganisms detected and counted through environmental monitoring methods

Some clean rooms are kept at a positive pressure so if any leaks occur, air leaks out of the chamber instead of unfiltered air coming in

BuildingCleanrooms maintain particulate-free air through the use of either HEPA or ULPA filters employing laminar or turbulent air flow principles

Laminar, or unidirectional, air flow systems direct filtered air downward in a constant stream towards filters located on walls near the clean room floor or through raised perforated floor panels to be re circulated

Laminar air flow systems are typically employed across 80% of a clean room ceiling to maintain constant air processing

Stainless steel or other non shedding materials are used to construct laminar air flow filters and hoods to prevent excess particles entering the air

Turbulent, or non unidirectional, air flow uses both laminar air flow hoods and nonspecific velocity filters to keep air in a clean room in constant motion, although not all in the same direction.

The rough air seeks to trap particles that may be in the air and drive them towards the floor, where they enter filters and leave the clean room environment

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Classmaximum particles/ft3

ISOequivalent≥0.1 µm ≥0.2 µm ≥0.3 µm ≥0.5 µm ≥5 µm

1 35 7.5 3 1 0.007 ISO 3

10 350 75 30 10 0.07 ISO 4

100 3,500 750 300 100 0.7 ISO 5

1,000 35,000 7,500 3000 1,000 7 ISO 6

10,000 350,000 75,000 30,000 10,000 70 ISO 7

100,000 3.5×106 750,000 300,000 100,000 700 ISO 8

US FED STD 209E clean room standards

Because 1 m3 is about 35 ft3, the two standards are mostly equivalent when measuring 0.5 µm particles, although the testing standards differ

Ordinary room air is around class 1,000,000 or ISO 9

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A fitting is used in pipe plumbing systems to connect straight pipe or tubing sections, to adapt to different sizes or shapes, and for other purposes, such as regulating or measuring fluid flow

The term plumbing is generally used to describe conveyance of water, gas, or liquid waste in ordinary domestic or commercial environments, whereas piping is often used to describe high-performance (e.g. high pressure, high flow, high temperature, hazardous materials) conveyance of fluids in specialized applications

The term tubing is sometimes used for lighter-weight piping, especially types that are flexible enough to be supplied in coiled form

Fittings (especially uncommon types) require money, time, materials, and tools to install, so they are a non-trivial part of piping and plumbing systems

Valves are technically fittings, but are usually discussed separately

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BuildingWater pipes are pipes or tubes, frequently made of polyvinyl chloride (PVC/uPVC), ductile iron, steel, cast iron, polypropylene, polyethylene, copper, or (formerly) lead,

that carry pressurized and treated fresh water to buildings (as part of a municipal water system), as well as inside the building

Tap water can sometimes appear cloudy, and this is often mistaken for a mineral impurity in the water

Cloudy water is usually caused by air bubbles coming out of solution in the water

Because cold water holds more air than warm water, small bubbles will appear in water

It has a high dissolved gas content that is heated or depressurized, which reduces how much dissolved gas the water can hold

The harmless cloudiness of the water disappears quickly as the gas is released from the water

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A valve is a device that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways

Valves are technically valves fittings, in an open valve, fluid flows in a direction from higher pressure to lower pressure

Cross-sectional diagram of an open globe valve

1. body2. ports3. seat4. stem5. disc when valve is open6. handle or hand wheel when valve is open7. bonnet8. packing9. gland nut10. fluid flow when valve is open11. position of disc if valve were shut12. position of handle or hand wheel if valve were shut

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Carpentry is a skilled trade in which the primary work performed is the cutting, shaping and installation of building materials during the construction of buildings, ships, timber bridges, concrete formwork, etc.

Carpenters traditionally worked with natural wood and did the rougher work such as framing, but today many other materials are also used and sometimes the finer trades of cabinetmaking and furniture building are considered carpentry

Carpentry is often hazardous work. Types of woodworking and carpentry hazards include Machine hazards, flying materials, tool projection, fire and explosion, electrocution, noise, vibration, dust and chemicals

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Gypsum board is primarily used as a finish for walls and ceilings, and is known in construction as drywall, sheetrock or plasterboard

Drywall may become damaged when exposed to water, especially if the drywall remains exposed to the water for an extended period of time

Often, when a room features drywall installed and an unintended introduction of water occurs and the water comes into contact with the drywall at the base of the wall where the drywall touches the ground, wicking will occur

Capillary action may introduce moisture anywhere from several inches to several feet above the floor depending upon the length of time the wall is exposed to water and how long the drywall remains in contact with the water supply

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Drywall (also known as plasterboard, wallboard, gypsum board, sheetrock, or LAGYP) is a panel made of gypsum plaster pressed between two thick sheets of paper

It is used to make interior walls and ceilingsDrywall construction became prevalent as a speedier alternative to traditional lath and plaster

Water that enters a room from overhead may cause ceiling drywall tape to separate from the ceiling as a result of the grooves immediately behind the tape where the drywall pieces meet become saturated

The drywall may also soften around the screws holding the drywall in place and with the aid of gravity, the weight of the water may cause the drywall to sag and eventually collapse, requiring replacement

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Aluminum is remarkable for the metal's low density and for its ability to resist corrosion due to the phenomenon of passivation

Structural components made from aluminum and its alloys are vital to the aerospace industry and are important in other areas of transportation and structural materials

The most useful compounds of aluminum, at least on a weight basis, are the oxides and sulfates

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Aluminum is a relatively soft, durable, lightweight, ductile and malleable metal with appearance ranging from silvery to dull gray, depending on the surface roughness

It is nonmagnetic and does not easily ignite

Aluminum is a good thermal and electrical conductor, having 59% the conductivity of copper, both thermal and electrical, while having only 30% of copper's density

Aluminum is capable of being a superconductor, with a superconducting critical temperature of 1.2 Kelvin and a critical magnetic field of about 100 gauss (10 milliteslas

Corrosion resistance can be excellent due to a thin surface layer of aluminum oxide that forms when the metal is exposed to air, effectively preventing further oxidation

The strongest aluminum alloys are less corrosion resistant due to galvanic reactions with alloyed copper

This corrosion resistance is also often greatly reduced by aqueous salts, particularly in the presence of dissimilar metals.

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A metal (from Greek "μέταλλον" – métallon, "mine, quarry, metal"is a solid material (an element, compound, or alloy) that is typically hard, opaque, shiny, and features good electrical and thermal conductivity

Metals are generally malleable—that is, they can be hammered or pressed permanently out of shape without breaking or cracking—as well as fusible (able to be fused or melted) and ductile (able to be drawn out into a thin wire)

About 91 of the 118 elements in the periodic table are metals (some elements appear in both metallic and non-metallic forms)

Metals are usually inclined to form cations through electron loss, reacting with oxygen in the air to form oxides over various timescales (iron rusts over years, while potassium burns in seconds)

The transition metals (such as iron, copper, zinc, and nickel) are slower to oxidize because they form passivating layer of oxide that protects the interior. Others, like palladium, platinum and gold, do not react with the atmosphere at all.

Some metals form a barrier layer of oxide on their surface which cannot be penetrated by further oxygen molecules and thus retain their shiny appearance and good conductivity for many decades (like aluminium, magnesium, some steels, and titanium

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Metals in general have high electrical conductivity, high thermal conductivity, and high density

Typically they are malleable and ductile, deforming under stress without cleaving. In terms of optical properties, metals are shiny and lustrous

Sheets of metal beyond a few micrometers in thickness appear opaque, but gold leaf transmits green light

Although most metals have higher densities than most nonmetals, there is wide variation in their densities, Lithium being the least dense solid element and osmium the densest

The alkali and alkaline earth metals in groups I A and II A are referred to as the light metals because they have low density, low hardness, and low melting points

BuildingAn alloy is a mixture of two or more elements in which the main component is a metal

Most pure metals are either too soft, brittle or chemically reactive for practical use

Combining different ratios of metals as alloys modifies the properties of pure metals to produce desirable characteristics

The aim of making alloys is generally to make them less brittle, harder, resistant to corrosion, or have a more desirable color and luster

Of all the metallic alloys in use today, the alloys of iron (steel, stainless steel, cast iron, tool steel, alloy steel) make up the largest proportion both by quantity and commercial value

Iron alloyed with various proportions of carbon gives low, mid and high carbon steels, with increasing carbon levels reducing ductility and toughness

The addition of silicon will produce cast irons, while the addition of chromium, nickel and molybdenum to carbon steels (more than 10%) results in stainless steels

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Structural steel is steel construction material, a profile, formed with a specific shape or cross section and certain standards of chemical composition and mechanical properties. Structural steel shape, size, composition, strength, storage, etc., is regulated in most industrialized countries

A hollow structural section (HSS) is a type of metal profile with a hollow tubular cross section

A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases (fluids), slurries, powders, masses of small solids

It can also be used for structural applications; hollow pipe is far stiffer per unit weight than solid members

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Wood is a hard, fibrous structural tissue found in the stems and roots of trees and other woody plants

It has been used for thousands of years for both fuel and as a construction material

It is an organic material, a natural composite of cellulose fibers (which are strong in tension) embedded in a matrix of lignin which resists compression

Wood is a heterogeneous, hygroscopic, cellular and anisotropic material

It is composed of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%)

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A plank is a piece of timber that is flat, elongated, and rectangular with parallel faces that are higher and longer than wide. Used primarily in carpentry, planks are critical in the construction of ships, houses, bridges, and many other structures

Usually made from sawed timber, planks are usually more than 1 1⁄2 in (38 mm) thick, and are generally wider than 2 1⁄2 in (64 mm)

In the United States, planks can be any length and are generally a minimum of 2 in (51 mm) deep by 8 in (200 mm) wide, but planks that are 2 in (51 mm) by 10 in (250 mm) and 2 in (51 mm) by 12 in (300 mm) are more commonly stocked by lumber retailers

Planks are often used as a work surface on elevated scaffolding, and need to be wide enough to provide strength without breaking when walked on

The wood is categorized as a board if its width is less than 2 1⁄2 in (64 mm), and its thickness is less than 1 1⁄2 in (38 mm). also serve as supports to form shelves and tables

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A cement is a binder, a substance that sets and hardens as the cement dries and also reacts with carbon dioxide in the air dependently, and can bind other materials together, made from crushed rock with burnt lime as binder

The volcanic ash and pulverized brick additives that were added to the burnt lime to obtain a hydraulic binder are referred to as cement

Portland cement is by far the most common type of cement in general use around the world. This cement is made by heating limestone (calcium carbonate) with small quantities of other materials (such as clay) to 1450 °C in a kiln, in a process known as calcination, whereby a molecule of carbon dioxide is liberated from the calcium carbonate to form calcium oxide, or quicklime, which is then blended with the other materials that have been included in the mix

The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum into a powder to make 'Ordinary Portland Cement', the most commonly used type of cement (often referred to as OPC). Portland cement is a basic ingredient of concrete, mortar and most non-specialty grout

The most common use for Portland cement is in the production of concrete. Concrete is a composite material consisting of aggregate (gravel and sand), cement, and water. As a construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural (load bearing) element. Portland cement may be grey or white

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A tile is a manufactured piece of hard-wearing material such as ceramic, stone, metal, or even glass, generally used for covering roofs, floors, walls, showers, or other objects such as tabletops.

Alternatively, tile can sometimes refer to similar units made from lightweight materials such as perlite, wood, and mineral wool,

typically used for wall and ceiling applications. In another sense, a tile is a construction tile or similar object, such as rectangular counters used in playing games (see tile-based game)

From the Latin word tegula, meaning a roof tile composed of fired clay. Tiles are often used to form wall and floor coverings, and can range from simple square tiles to complex mosaics

Tiles are most often made of ceramic, typically glazed for internal uses and unglazed for roofing, but other materials are also commonly used, such as glass, cork, concrete and other composite materials, and stone

Tiling stone is typically marble, onyx, granite or slate. Thinner tiles can be used on walls than on floors, which require more durable surfaces that will resist impacts

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A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling

Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous (e.g., a glass)

Because most common ceramics are crystalline, the definition of ceramic is often restricted to inorganic crystalline materials, as opposed to the noncrystalline glasses,

Ceramics are glazed and fired to create a colored, smooth surface, now include domestic, industrial and building products and a wide range of ceramic art

In the 20th century, new ceramic materials were developed for use in advanced ceramic engineering; for example, in semiconductors

Building : Tell the name of the tools

How Do I Test a Phone Line With a MultimeterIf no reading comes up when testing the phone lines, they are not touching

In order for a phone line to function properly, it needs to be an independent circuit that does not touch any other phone lines

Should one phone line come in contact with another phone line, both phone lines will stop functioning properly. You can determine if your phone lines are touching by using the "Continuity" setting on your digital multimeter at the network interface device installed on the exterior wall of your house

Instructions1.1 Disconnect anything connected to a telephone jack in the house. You need the telephone lines to be open in order to test them

1.2 Locate the network interface device box, or NID, for your phone service. It is a large grey box with the words "Telephone Network Interface" printed on it and is usually installed by your telephone company on one of the exterior walls of your house near your electrical meter. This box is where your phone lines connect to your telephone company's wiring loop, so it must be located somewhere near or on your property. If you cannot find your NID, contact your telephone service provider for its exact location

1.3 Unscrew the screws labeled "Customer Access" on the NID's customer access cover with a screw driver and remove the cover. Any screws that are not labeled "Customer Access" can only be removed by the telephone company that installed the NID

How Do I Test a Phone Line With a Multimeter

4 . Disconnect the phone lines that you want to test from their NID test jacks. Once disconnected, the phone lines will be completely open and ready for testing. Wait one minute with the phone lines disconnected before proceeding to allow any electricity in the lines to dissipate

5 . Set the digital multimeter to its continuity setting. This setting is usually marked by a symbol that resembles a sound wave, but see the documentation that came with your device for specific instructions

6 . Touch the tips of the digital multimeter's leads together. If the multimeter is functioning properly, a reading will appear on its digital screen and it will emit a beeping noise

7 . Connect one of the digital multimeter's leads to one phone wire and connect the second lead to another phone wire. If the multimeter does not detect any continuity, the phone lines are not touching. If it does detect continuity, the phone lines are touching somewhere and will not function properly

8 . Repeat the test for each pair of phone lines. Once every pair has been tested, you will know which phone lines work and which phone lines do not.

How to Troubleshoot Phone Systems

Check each phone1 Check each phone to make sure none were left off the hook. Re-plug each phone into its jack to eliminate the possibility of a loose connector

2 Lift the handset of each phone and check if the ringer volume has been set to minimum level or if the phone is on mute

3 Take your phones over to a friend's or neighbor's house and plug each one into a working phone jack. Listen for a dial tone to detect any defective phone set

Check the network interface device, modems and other peripheral equipment

4 Find the network interface device, or NID, mounted by the telephone company on a wall just outside your home. Follow the cable running from the utility pole into your home to trace its location. Open the NID and look inside for the short wire with a modular plug connector into a test jack. Unplug the connector from its jack. Get a working phone, plug it into the jack, and listen for a dial tone. No dial tone would indicate that there is no power coming from the telephone company. Call the phone company to report the problem if you do not hear one

5 Unplug the modular connector inside the NID to disconnect power from the main telephone line. Unscrew each jack faceplate with a screwdriver and check the terminals' screws behind the plate for any loose connection or wires that may have come in contact with each other. Tighten any loose terminal screws, and bend away any wires that touch using a pair of needle nosed pliers. Replug the main line in the NID and plug a phone into the wall jack to check for a dial tone

6 Unplug any peripheral devices connected to your phone line such as security system equipment, Internet router, fax machine, modem or caller ID box. Check your phone for a dial tone. If there is a dial tone, then one of the devices caused the problem. Replug each device one at a time and check the dial tone to see which one will cause the phone line to malfunction

Thank You

L | C | LOGISTICS

PLANT MANUFACTURING AND BUILDING FACILITIES EQUIPMENTEngineering-Book

ENGINEERING FUNDAMENTALS AND HOW IT WORKS

MECHANICS BUILDING GENERAL