23 ) CAR PARTZ FOR ALPHABET " E "

EGR Valve Description
The EGR Valve is an integral part of your engine?s emissions and ignition systems. On older vehicles, the Engine EGR Valve can be mechanical and on later models the EGR Valve is generally electronic. The EGR Valve Location is typically housed on the intake manifold and permits a measured amount of exhaust gasses back into the engine. Regardless of construction the EGR Valve plays a key role in reducing unwanted engine emissions as well as reducing engine knock. This means that getting the application specific EGR Valve that?s perfect for your car, truck, van or SUV is essential. And our state of the art parts locating system makes it easy to find the application specific EGR Valve for your car, truck, van or SUV?s combination of engine, model and year. When it comes to meeting emission testing requirements and reducing engine knock, a ?close enough? EGR Valve isn?t a good enough EGR Valve. This doesn?t mean you have to buy an expensive EGR Valve. Nobody beats our price on any brand of EGR Valve. Whether you vehicle is a family sedan or a high performance job, our low prices mean you get the best EGR Valve that your money can buy. Add to our low EGR Valve prices and unequalled EGR Valve selection fast and secure delivery. It?s easy to see why we should be your one source for every EGR Valve need.




Emblem Description
When it comes to classic elegance and unmatched automotive craftsmanship, car manufacturers have prided themselves with their unique and exceptional concepts of practical mobility. Taking marketing leverage on their aerodynamic styling as well as elusive vehicle form and function, they have built solid reputations among the innovations and convenience offered by their lines of automobile design series. To specifically represent their tasteful automotive craftsmanship, they make use of emblem constructions to create distinction between car manufacturers. While emblems are signatories of their image and reputation in approaching the customers, the part has not been taken lightly when it comes to design and application. Although the part is nothing but brand marques, they are proudly crafted from silver, chrome, and gold plating or finishes that surely command attention with its presence. Even emblems have nothing to do with how your vehicle runs and performs; it never hurts to swell onto your vain side. The part is a great indicator of classic image of elegance and pride symbolizing exactly how you feel in owning your precious ride. To keep them at their gleaming glory, nothing beats routine cleaning and polishing to keep them from the ruining effects of contaminants. While they are strategically located at the front, rear, or side fascias of your vehicle for excellent visibility, they are also subject to street and off road hassles which come inevitable with daily driving conditions. Emblems are purely about class and elite distinction to proudly owning such an excellent taste of investment. While rusty emblem constructions will not affect your vehicle?s drivability, bringing back your vehicle?s identity is simple by polishing its looks with new emblem replacement. As a trusted source of genuine and high quality parts and accessories, you can rely on our site to cover your immediate replacement needs. Check out our online catalog to be provided with the selections of emblems available for your vehicle?s specific year, model, and make of vehicle. Avoid time-consuming and frustrating product location by completing your car restoration and styling project needs right in our convenient 24/7 online shopping store.



Engine Mount Description
to dampen the effects of vibrations and oscillations. While your vehicle constantly adapts to road irregularities, the part secures your engine in place and in position to prevent serious damages. Over time, the part will give in to wear and tear due to prolonged usage. Keeping track of the working conditions of the part is crucial to eliminate the risks of total engine breakdown due to failure. Fortunately, quality factory equivalents to you original engine mounts are conveniently available. Having your vehicle equipped with severe duty and heavy duty engine mount for replacements is never wrong economy for it greatly influences the overall performance and of your ride. Attached to the framework of your under chassis, the part?s main function is to cushion the engine assembly against shaking and shifting which could instantly foul up your ride?s critical factory settings for performance and fuel economy. Aside from dampening the effects of the rigor of daily commutes and long drives, the part also minimizes the noise and engine vibration that reaches through the interior cabin. Failure to your engine mounts could seriously damage your engine due to imprecision. Cabin comfort and dependable engine assembly support best explains the need to invest with precision fitting and quality engine mount replacements at the first sign of damage. Putting up with the use of wearing and already damage mounts is wrong economy for its risks your chances of facing expensive repairs and part replacements expenses due to engine failure. Quality auto-part replacements guarantee product longevity and dependable service which are crucial to continually enjoying the excellent handling features of your ride. For your next scheduled replacements, visit our online shopping store for a trusted source of quality and custom fitting engine mounts. Consult our vehicle fitment listings to make sure that your deal with the right product application that completes your automotive shopping list.




Exhaust Description
Upgrading your car, truck, or SUV's auto exhaust system is a great way to build horsepower, free up trapped torque, and improve upon anemic-sounding factory systems. The larger pipes, low-restriction mufflers, and tuned resonators of a well-designed performance exhaust system can make a world of difference on your vehicle. We have truck and auto exhaust systems from Flowmaster exhaust, Gibson exhaust, and a host of other highly-respected exhaust system manufacturers, with applications ranging from Honda Civic exhaust systems to LS1 Camaro exhaust systems. Those of you with newer vehicles are no doubt thinking, "what about emission control regulations?" The government doesn't take kindly to bypassing smog equipment, something the smart tuner keeps in the back of his or her mind whenever an upgrade is planned. Enter the cat-back exhaust system: For newer vehicles, Flowmaster exhaust, Gibson exhaust, and many of our other premium manufacturers make cat-back exhaust systems (short for catalyst-back exhaust systems) to fit your needs. These cat-back exhaust systems leave the emissions-control gear in place, but allow you to put large-diameter exhaust pipes and low-restriction performance mufflers into the system after the catalytic converter. The net result is lower auto exhaust backpressure, more horsepower, more torque, and a much hotter sound, all while staying perfectly legal.



Exhaust Manifold Description
Each component attached to your ride performs a variety of functions that are directly related to the performance of your vehicle. One of these is the exhaust manifold. The function of this exhaust system component may not be complex, but your vehicle would definitely not perform properly without them. Exhaust manifolds are a network of passages that routes the exhaust gases from the various exhaust ports toward the mufflers and catalysts of the exhaust system. The number and design of the exhaust manifolds depend on the cylinder heads to which they are attached for efficiency in gathering exhausts from each of the individual exhaust ports. A single exhaust manifold can be found on vehicles with linear engines. On the other hand, v-shaped engines are equipped with two exhaust manifolds, one mounted to each cylinder head. Exhaust manifolds can be made of tubular steel, lightweight aluminum or cast iron. A ticking, popping or tapping sound can be heard as an indication of a leaking exhaust manifold. Do not take this for granted, because a more serious damage to your vehicle would happen if you do not find an immediate replacement for them. Visit our online site and browse our online catalog for a view of our wide selection of exhaust manifolds. No matter what car make or model you own, we have it in stock for you! You can place your order through our online order form or by simply dialing our toll free hotline number. Call now and be one of our satisfied customers!




Expansion Tank Description
The coolant expands as your engine heats up during the combustion process. Because of this, the thermal fluid inside your engine has the possibility of flowing out of the overflow tube and eventually into the street. The coolant is essential for a successful operation of your heat transfer, so your car has been pre-installed with an expansion tank. Also known as a coolant reservoir, this cooling system part provides an extra space for the coolant. The expansion tank can also remove bubbles from the entire cooling system to absorb heat much faster. But its primary function is to absorb the expansion of the coolant as it gradually increases into full operating temperature. The expansion tank is a see-through plastic container that can be seen mounted into the overflow tube from the radiator. With a properly working expansion tank, your radiator is always full even if the coolant inside it rises and falls. Just make sure that your expansion tank has an expansion tank cap, since this spring-loaded valve maintains the proper coolant level in your cooling system at predetermined levels. At one time or another, you may see the need to replace your stock expansion tank. When this happens, it is important that you find a replacement part that is equal to the volume of your existing tank. Get an efficient cooling system every time with a properly working expansion tank. Stop looking somewhere else, because you can easily find one that will suit your car model. Placing an order is so much easy! You can log on to our site and fill out our online order form, or simply dial our toll free hotline number. Do not worry, because all your orders will be promptly processed by our highly trained customer service representatives. Most of all, you can place your orders anytime you find most convenient?twenty four hours a day, seven days a week!

22 ) TEXTILE ENGINEERING

Textile engineering (TE) or textile technology deals with the application of scientific and engineering principles to the design and control of all aspects of fiber, textile, and apparel processes, products, and machinery. These include natural and man-made materials, interaction of materials with machines, safety and health, energy conservation, and waste and pollution control. Additionally, textile engineers are given training and experience in plant design and layout, machine and wet process design and improvement, and designing and creating textile products.


Courses
The courses taken in a typical TE degree program include Textile Engineering Systems, Textile Engineering Design, Mechanics of Fibrous Structures, Textile Engineering Quality Improvement, Textile Information Systems Design, Polymer Engineering, Polymeric Biomaterials Engineering, Mechanics of Tissues & Implants Requirements, Fabric Building Mechanisms, Special Topics in Textile Engineering, Dynamics of Fabric Production Systems, Textile Composites, Polymeric Biomaterials Engineering, Industrial Textiles, Textile Applications in Medicine, Engineering Economics, Basic Electronics of Textile Manufacturing and Quality Testing Machinery, Dyeing, Printing and other methods of textile coloration, and Industrial Planning and Organization (Moi University, 1991).

Throughout the Textile Engineering curriculum, students take classes from other engineering and disciplines including: Mechanical, Chemical, Materials and Industrial Engineering Disciplines. The TE curriculum provides a broad base of fundamental engineering courses as a foundation for studies in textile engineering. Students also learn such fundamental courses as Thermodynamics, Materials Science, Industrial Management, Applied Mechanics, and Engineering Drawing and Design.


Job profile
A textile engineer therefore works with textile materials: fibers, yarns, fabrics, and finishes. Most textile engineers work on product research and development, either improving current textile based products or creating new products. They may also be involved with finding uses for new fibers, yarns, fabrics, or textile finishes.


1- TEXTILE INDUSTRY
An industry (from Latin industrius, "diligent, industrious") is the manufacturing of a good or service within a category. Although industry is a broad term for any kind of economic production, in economics and urban planning industry is a synonym for the secondary sector, which is a type of economic activity involved in the manufacturing of raw materials into goods and products.

There are four key industrial economic sectors: the primary sector, largely raw material extraction industries such as mining and farming; the secondary sector, involving refining, construction, and manufacturing; the tertiary sector, which deals with services (such as law and medicine) and distribution of manufactured goods; and the quaternary sector, a relatively new type of knowledge industry focusing on technological research, design and development such as computer programming, and biochemistry. A fifth quinary sector has been proposed encompassing nonprofit activities. The economy is also broadly separated into public sector and private sector, with industry generally categorized as private. Industries are also any business or manufacturing.

Industry in the sense of manufacturing became a key sector of production and labour in European and North American countries during the Industrial Revolution, which upset previous mercantile and feudal economies through many successive rapid advances in technology, such as the steel and coal production. It is aided by technological advances, and has continued to develop into new types and sectors to this day. Industrial countries then assumed a capitalist economic policy. Railroads and steam-powered ships began speedily establishing links with previously unreachable world markets, enabling private companies to develop to then-unheard of size and wealth. Following the Industrial Revolution, perhaps a third of the world's economic output is derived from manufacturing industries—more than agriculture's share.

Many developed countries (for example the UK, the U.S., and Canada) and many developing/semi-developed countries (People's Republic of China, India etc.) depend significantly on industry. Industries, the countries they reside in, and the economies of those countries are interlinked in a complex web of interdependence.

1-1 MIXING COTTON
Cotton is a hygroscopic material , hence it easily adopts to the atmospheric airconditions. Air temperature inside the mxing and blowroom area should be more than 25 degree centigrade and the relative humidity(RH%) should be around 45 to 60 %, because high moisture in the fibre leads to poor cleaning and dryness in the fibre leads to fibre damages which ultimately reduces the spinnability of cotton.

Cotton is a natural fibre. The following properties vary very much between bales (between fibres) fibre micronaire fibre length fibre strength fibre color fibre maturity Out of these , fibre micronaire, color, maturity and the origin of growth results in dye absorption variation.
There fore it is a good practice to check the maturity , color and micronaire of all the bales and to
maintain the following to avoid dye pick up variation and barre in the finished fabric.



1.2- BLOWROOM PROCESS

Basic operations in the blowroom:
opening
cleaning
mixing or blending
microdust removal
uniform feed to the carding machine
Recycling the waste

Blow room installations consists of a sequence of different machines to carry out the above said
operations.Moreover Since the tuft size of cotton becomes smaller and smaller, the required intensities of processing necessitates different machine configuration.


1.3- CARDING PROCESS
Card is the heart of the spinning mill" and "Well carded is half spun" are two proverbs of the experts.
These proverbs inform the immense significance of carding in the spinning process.High production in carding to economise the process leads to reduction in yarn quality.Higher the production, the more sensitive becomes the carding operation and the greater danger of a negative influence on quality.The technological changes that has taken place in the process of carding is remarkable. Latest machines achieve the production rate of 60 - 100 kgs / hr, which used to be 5 - 10 kgs / hr, upto 1970.


THE PURPOSE OF CARDING:
to open the flocks into individual fibres
cleaning or elimination of impurities
reduction of neps
elimination of dust
elimination of short fibres
fibre blending
fibre orientation or alignment
sliver formation



1.4- METALLIC CARD CLOTHING
As Carding machine design improved in 1950's and 60's, it became apparent that card clothing was a limiting factor


Much time and effort was spent in the development of metallic card clothing.
There are two rules of carding


The fibre must enter the carding machine, be efficiently carded and taken from it in as little time as possible
The fibre must be under control from entry to exit
Control of fibres in a carding machine is the responsibilitgy of the card clothing
Following are the five types of clothings used in a Carding machine


Cylinder wire
Doffer wire
Flat tops
Licker-in wire
Stationary flats

CYLINDER WIRE: The main parameters of CYLINDER Card clothing
Tooth depth
Carding angle
Rib width
Wire height
Tooth pitch
Tooth point dimensions

1.5- RING FRAME
The ring spinning will continue to be the most widely used form of spinning machine in the near future,
because it exhibits significant advantages in comparison with the new spinning processes.



Following are the advantages of ring spinning frame

It is universaly applicable, i.e.any material can be spun to any required count
It delivers a material with optimum charactersticss, especially with regard to structure and strength.
it is simple and easy to master
the know-how is well established and accessible for everyone

1.6- WINDING
Ring spinning produces yarn in a package form called cops.

Since cops from ringframes are not suitable for further processing, the winding process serves to achieve additional objectives made necessary by the requirements of the subsequent processing stages.

Following are the tasks of winding process

Extraction of all disturbing yarn faults such as the short, long thick ,long thin, spinners doubles, etc
Manufacture of cones having good drawing - off properties and with as long a length of yarn as possible
paraffin waxing of the yarn during the winding process
introduction into the yarn of a minimum number of knots
achievement of a high machine efficiency i.e high produciton level
The winding process therefore has the basic function of obtaining a larger package from several small ring bobbins. This conversion process provides one with the possibility of cutting out unwanted and problematic objectionable faults. The process of removing such objectionable faults is called as yarn ‘ clearing’ .

1.7- YARN CONDITIONING
Why conditioning is required?

Moisture in atmosphere has a great impact on the physical properties of textile fibres and yarns.

Relative humidity and temperature will decide the amount of moisure in the atmosphere. High relative humidity in different departments of spinning is not desirable. It will result in major problems. But on the otherhand, a high degree of moisture improves the physical properties of yarn. Moreover it helps the yarn to attain the standard moisture regain value of the fibre. Yarns sold with lower moisture content than the standard value will result in monetary loss. Therefore the aim of CONDITIONING is to provide an economical device for supplying the necessary moisture in a short time, in order to achieve a lasting improvement in quality.

21 ) BUSINESS ELECTRONICZ

How Energy-efficient Electronics Work

The average American household spends $1,400 each year on energy bills [source: Forbes]. Home heating and cooling systems are responsible use about 45 percent of the energy. Lighting takes up another significant chunk, especially if you're slow to switch to efficient compact fluorescent bulbs. But some of the most energy-hungry machines making your electric bill creep higher every month are your electronic devices.


The Xbox 360 uses 187 watts of electricity


Take a look at your TV, for example. Maybe you recently splurged on one of those 40-inch (102-centimeter) plasma TVs, which requires 350 watts of energy to run. Connected to the TV is an Xbox 360 (187 watts), a PlayStation 3 (197 watts) and a digital video recorder (DVR) (33 watts) [source: CNET]. Wonder where your money's going each month? Straight into that black hole of energy consumption in your living room. Luckily, electronics manufacturers are designing equipment, appliances and gadgets that are more energy efficient.

Energy conserving electronics are not only better for our wallets, but better for the environment. More than half the electricity in the United States comes from coal-burning power plants [source: American Society of Mechanical Engineers]. Even a brand-new coal-burning power plant sends out 6 million tons (5.4 million metric tons) of carbon dioxide each year, 1,200 tons (1,089 metric tons) of sulfur dioxide and 1,600 tons (1,452 metric tons) of nitrogen oxide [source: Las Vegas Sun]. These chemicals not only deplete the ozone layer but contribute to acid rain and respiratory illness in children and the elderly.

So what can you do to cut your electric bill and clean up the air? Are there government and industry resources that can tell you which products are more efficient? And what types of TVs, computers and handheld electronics give the most bang for the energy buck? Read on to find out.


Energy Star and Other Energy-conserving Initiatives

In 1992, the U.S. Environmental Protection Agency (EPA) introduced a new program called Energy Star to show consumers how much energy the products they buy actually use. Since its inception, 12,000 electronics and appliance manufacturers have voluntarily complied with increasingly strict Energy Star standards. As a result, more than 40,000 individual products boast the highly recognizable Energy Star label [source: Energy Star].

Energy Star first began with computers and computer monitors. Over the years, the product categories and published standards have expanded to include residential heating and cooling systems, home appliances, lighting systems, and every type of office and home electronics equipment.




The Energy Star logo is a
familiar sight on the
packaging of thousands
of consumer electronics.

In 2007 alone, Americans using Energy Star products helped prevent 40 million metric tons (44.1 tons) of greenhouse gas from entering the atmosphere [source: Energy Star]. That's the equivalent of taking 27 million cars off the road for an entire year. The EPA also estimates that in 2007, Americans using Energy Star products saved $16 billion on their electric bills [source: Energy Star].


Energy Star is the most recognizable energy-conservation initiative for consumer electronics, but it's not the only one. The Electronic Product Environmental Assessment Tool (EPEAT) is a newer rating system that grades the overall environmental impact of various consumer electronics products. Among the criteria are how much of the gadget's materials can be recycled, whether any of the components are toxic and whether the product meets existing or pending Energy Star standards.
Energy Star is the most recognizable energy-conservation initiative for consumer electronics, but it's not the only one. The Electronic Product Environmental Assessment Tool (EPEAT) is a newer rating system that grades the overall environmental impact of various consumer electronics products. Among the criteria are how much of the gadget's materials can be recycled, whether any of the components are toxic and whether the product meets existing or pending Energy Star standards.


Products that meet all of EPEAT's required criteria earn a bronze label. Those that meet all required criteria plus 50 percent of optional standards get a silver label, and those that meet all required criteria plus 75 percent or more of the optional standards get a gold rating.


All computers require a power supply, a small box that converts AC power coming from the wall to the DC power that runs the device. Historically, a lot of energy was lost in this conversion process. In 2004, a new incentive program called 80 Plus was funded by American utility companies to encourage manufacturers to build more efficient power supplies for desktop and notebook computers and servers. To qualify for an 80 Plus rating, a power supply must be 80 percent efficient or greater.


Over the years, American utility companies have funded more than $5 million worth of incentives for computer makers and power supply manufacturers to improve the efficiency of their products. As a result, more than 600 power supplies that have achieved the 80 Plus rating [source: 80 Plus]. And even better, the recently published Energy Star standards for new computers requires that internal power supplies carry the 80 Plus seal of approval.

Televisions are some of the biggest energy hogs in your house. Let's look at the most and least efficient types of TVs and what's on the horizon for greening the small screen.


Energy-efficient TVs

Television screens are getting bigger, sharper and thinner every year. While the action on the screen looks better than ever, the effect on your electric bill can be downright scary. The average American still only pays around $24 a year to power his or her TV, but that average is dragged down by all of the old CRT (cathode ray tube) TVs that will be replaced as more people upgrade to power-sucking high-definition (HDTV) models [source: American Council for an Energy-efficient Economy].


According to testing by CNET labs, the most energy-efficient HDTV costs around $30 a year to power, while the most power-hungry model adds nearly $230 to the electric bill each year [source: CNET]. Larger screen size is one of the biggest contributors to this leap in the cost of watching TV. According to a study by the Natural Resource Defense Council, an HDTV with a 40-inch (102-centimeter) screen or larger consumes more energy per year than any other device or appliance in the house, including a 22.5 cubic foot (0.6 cubic meter) refrigerator [source: Energy Star].


Different television technologies also burn through different amounts of electricity. Plasma TVs are, on average, the least efficient technology. Next come LCDs, followed by projection TVs and traditional CRTs [source: CNET]. But even within these general categories, there are many factors that can make a TV either an energy sipper or a guzzler. Incredibly, both the most efficient and the least efficient TVs on CNET's list are LCDs.


In addition to the power they use while they're on, many of these large-screen TVs don't shut off completely when you press the power button. The manufacturers felt that people wouldn't want to wait so long for their sets to warm up when they press the power button, so they have the TVs go into a standby mode rather that shut off completely. Some of them require you to press a separate button or unplug the unit entirely to totally power down the equipment


The Philips 42PFL5603D, or Eco TV



As consumers become more energy conscious, TV makers are responding with innovative, energy-saving designs. One example is the Philips 42PFL5603D, also known as the Eco TV. When you activate the Eco TV's power saver mode, the television uses a trio of sensors to optimize the intensity of the LCD's backlight. The brighter the room, the harder the backlight needs to work. The Eco TV can detect the relative darkness and brightness of the room and adjust how much light it uses to illuminate the picture. In addition, the Eco TV boasts a sensor that constantly adjusts for the brightness of the scene being played on the TV. If the scene takes place at night, the backlight dims ever-so-slightly to save energy for the daytime scenes.


Another TV technology called organic light-emitting diodes (OLED) offers an even more energy efficient way to light a large TV screen. With OLED, light isn't provided by a backlight, but by individual molecules that light each pixel on the screen. The first small (30-inch, 76-cm) OLED TVs arrived in November 2007 and a consortium of Japanese electronics-makers are pushing to deliver large-screen versions within the year


TV Power Saving Tips

Even if you don't have a futuristic or "green" TV, there are still several things you can do to lower the energy impact of your TV:

•Power down the TV completely when you're not using it.
•See if your TV has some kind of power saver mode.
•Disable any "Quick Start" option that leaves the TV in standby mode as default.
•Manually dim the intensity of the backlight. The easiest way to do this is through the contrast and brightness controls.
•Watch TV in a dark room. It improves picture clarity while requiring less backlight.

Energy-saving Computers


Even the most energy-hungry home computer doesn't make much of a dent in the monthly electric bill. If you ran a desktop computer and monitor at full power for eight hours every day, it would add $30 to your annual energy costs [source: myGreenElectronics].


But imagine that you owned a business with hundreds of employees. Now imagine all of those desktop computers crowded into an office, plus the servers and storage units crammed into IT rooms. Not surprisingly, those computers eat up a lot of energy, accounting for up to 70 percent of a company's energy bill [source: Cranberry]. Computers also create heat and force the air conditioning to work even harder to keep the office cool.


Recently, several computer makers have introduced machines designed specifically to lower the energy costs of small and large businesses. One is the Earth PC and Earth Server by Tech Networks of Boston. These new PCs come with a patented power management system that keeps machines running as lightly as possible in standby mode. They also come with 80 Plus-certified power supplies which keep them cool and lower air conditioning bills by 33 percent in the process


The Cranberry SC20 smart client computer


The Cranberry SC20 is another new energy-conserving computer marketed toward businesses. The Cranberry isn't exactly a PC. Instead, it's something in between a full-fledged PC and what's known as a thin client. Thin clients are pared-down computer terminals that run all of their applications from a central server. Thin clients don't have hard drives and can't run their own native applications. The Cranberry is called a "Smart Client" because it's slim (the size of a paperback book), yet it can run its own software, be controlled locally and includes standard ports for connecting digital cameras, speakers and other devices. Because the applications reside on the Internet rather than on the machine, this is a form of cloud computing.


But the impressive thing about the Cranberry is that it uses just 10 percent of the power of a standard PC. That's because it has no moving parts (no fans or hard drive) and is powered by an extremely efficient microprocessor. The Cranberry consumes a mere 9 watts compared to a standard PC which burns through 175 watts.


The Mac Mini


The Mac Mini is another desktop computer touted for its energy efficiency. The Mini is a tiny 6.5-inch (16.5-cm)-square, white box with a built-in CD/DVD drive and the standard input/output jacks for USB and Firewire devices. But since it's stuffed with highly efficient notebook computer guts -- and has an external power supply -- it runs quiet and cool at only 25 watts. The latest Mac Mini meets Energy Star 4.0 standards and earned an Electronic Product Environmental Assessment Tool (EPEAT) Silver rating.


In terms of computer monitors, smaller LCD monitors are more energy efficient than CRT monitors of the same size -- some reports say 66 percent more efficient [source: flatpaneltv.org]. LCD monitors also give off less heat than CRTs and help save money on that air-conditioning bill.


Now let's look at some cool new handheld gadgets that keep going long after everyone else's batteries are drained.


Energy-saving Handhelds


Since handheld gadgets like cell phones, iPods and BlackBerrys run on batteries, sometimes we forget that charging and recharging adds to the electric bill. Thankfully some forward-looking companies are developing innovative ways to power the gadgets that run our lives.


The Eco Media Player is an iPod-like handheld device that can be loaded with music and video files via a standard SD memory card. What's not standard about this media player is that you can power up the battery with a hand crank that unfolds from of the back of the unit. One minute of cranking gets you 40 minutes of audio playing power [source: TreeHugger]. The technology is based on the famous hand-crank emergency radios that inventor Trevor Baylis developed for aid workers and villagers in rural Africa.


Alternative fuels are another way to get electronics off the power grid. A company called Angstrom Power recently presented a prototype cell phone at the 2008 Consumer Electronics Show that runs on a tiny hydrogen fuel cell. The company claims that its Micro Hydrogen fuel cell platform fits right into existing cell phones with no modifications and promises twice the talk time of a lithium-ion battery. The device can be fully charged in less than 10 minutes.


A simpler way to recharge a cell phone is to rig up a standard cell phone with a small, wearable solar panel. Several companies are selling small arrays of solar panels that can plug directly into cell phones or other mobile devices. A Japanese company called Strapyanext is selling a 12-cm (5-inch) solar cell phone charger that can produce and store roughly 40 minutes worth of talk time during 6 to 10 hours in the sun.



The Nokia Eco Sensor Concept and wrist sensor unit


Solar technology isn't limited to cell phones. The Nokia Eco Sensor Concept is a futuristic personal digital assistant (PDA) prototype that comes with a separate wrist sensor unit. The wrist sensor is made out of solar cells which provide energy for the PDA. This wrist sensor can also generate electricity by capturing kinetic energy from natural arm movements, like some watches already do today. The screen of the Nokia PDA will use a highly efficient technology called electrowetting. In place of pixels on a screen, it uses tiny drops of oil that expand and contract with electrical charges.

20 ) COMPUTERS ' POWER SUPPLIES

Power supply is a reference to a source of electrical power. A device or system that supplies electrical or other types of energy to an output load or group of loads is called a power supply unit or PSU. The term is most commonly applied to electrical energy supplies, less often to mechanical ones, and rarely to others.

Electrical power supplies
This term covers the power distribution system together with any other primary or secondary sources of energy such as:

Conversion of one form of electrical power to another desired form and voltage. This typically involves converting 120 or 240 volt AC supplied by a utility company (see electricity generation) to a well-regulated lower voltage DC for electronic devices. Low voltage, low power DC power supply units are commonly integrated with the devices they supply, such as computers and household electronics. For other examples, see switched-mode power supply, linear regulator, rectifier and inverter (electrical).
Batteries
Chemical fuel cells and other forms of energy storage systems
Solar power
Generators or alternators (particularly useful in vehicles of all shapes and sizes, where the engine has torque to spare, or in semi-portable units containing an internal combustion engine and a generator) (For large-scale power supplies, see electricity generation.)
Constraints that commonly affect power supplies are the amount of power they can supply, how long they can supply it without needing some kind of refueling or recharging, how stable their output voltage or current is under varying load conditions, and whether they provide continuous power or pulses.

The regulation of power supplies is done by incorporating circuitry to tightly control the output voltage and/or current of the power supply to a specific value. The specific value is closely maintained despite variations in the load presented to the power supply's output, or any reasonable voltage variation at the power supply's input. This kind of regulation is commonly categorized as a Stabilized power supply.

Power supply types
Power supplies for electronic devices can be broadly divided into linear and switching power supplies. The linear supply is a relatively simple design that becomes increasingly bulky and heavy for high current devices; voltage regulation in a linear supply can result in low efficiency. A switched-mode supply of the same rating as a linear supply will be smaller, is usually more efficient, but will be more complex.

Battery power supply
A battery is a type of linear power supply that offers benefits that traditional line-operated power supplies lack: mobility, portability, and reliability. A battery consists of multiple electrochemical cells connected to provide the voltage desired.

The most commonly used dry-cell battery is the carbon-zinc dry cell battery. Dry-cell batteries are made by stacking a carbon plate, a layer of electrolyte paste, and a zinc plate alternately until the desired total voltage is achieved. The most common dry-cell batteries have one of the following voltages: 1.5, 3, 6, 9, 22.5, 45, and 90. During the discharge of a carbon-zinc battery, the zinc metal is converted to a zinc salt in the electrolyte, and magnesium dioxide is reduced at the carbon electrode. These actions establish a voltage of approximately 1.5 V.

The lead-acid storage battery may be used. This battery is rechargeable; it consists of lead and lead/dioxide electrodes which are immersed in sulfuric acid. When fully charged, this type of battery has a 2.06-2.14 V potential. During discharge, the lead is converted to lead sulfate and the sulfuric acid is converted to water. When the battery is charging, the lead sulfate is converted back to lead and lead dioxide.

A nickel-cadmium battery has become more popular in recent years.This battery cell is completely sealed and rechargeable. The electrolyte is not involved in the electrode reaction, making the voltage constant over the span of the batteries long service life. During the charging process, nickel oxide is oxidized to its higher oxidation state and cadmium oxide is reduced. The nickel-cadmium batteries have many benefits. They can be stored both charged and uncharged. They have a long service life, high current availabilities, constant voltage, and the ability to be recharged.

Linear power supply
An AC powered linear power supply usually uses a transformer to convert the voltage from the wall outlet (mains) to a different, usually a lower voltage. If it is used to produce DC, a rectifier is used. A capacitor is used to smooth the pulsating current from the rectifier. Some small periodic deviations from smooth direct current will remain, which is known as ripple. These pulsations occur at a frequency related to the AC power frequency (for example, a multiple of 50 or 60 Hz).

The voltage produced by an unregulated power supply will vary depending on the load and on variations in the AC supply voltage. For critical electronics applications a linear regulator will be used to stabilize and adjust the voltage. This regulator will also greatly reduce the ripple and noise in the output direct current. Linear regulators often provide current limiting, protecting the power supply and attached circuit from overcurrent.

Adjustable linear power supplies are common laboratory and service shop test equipment, allowing the output voltage to be set over a wide range. For example, a bench power supply used by circuit designers may be adjustable up to 30 volts and up to 5 amperes output. Some can be driven by an external signal, for example, for applications requiring a pulsed output.

The simplest DC power supply circuit consists of a single diode and resistor in series with the AC supply. This circuit is common in rechargeable flashlights

A home-made linear power supply (used here to power amateur radio equipment


AC/ DC supply
In the past, mains electricity was supplied as DC in some regions, AC in others. A simple, cheap linear power supply would run directly from either AC or DC mains, often without using a transformer. The power supply consisted of a rectifier and a capacitor filter. The rectifier was essentially a conductor, having no sudden effect when operating from DC.

Switched-mode power supply
A switched-mode power supply (SMPS) works on a different principle. AC mains input is directly rectified without the use of a transformer, to obtain a DC voltage. This voltage is then sliced into small pieces by a high-speed electronic switch. The size of these slices grows larger as power output requirements increase.

The input power slicing occurs at a very high speed (typically 10 kHz — 1 MHz). High frequency and high voltages in this first stage permit much smaller step down transformers than are in a linear power supply. After the transformer secondary, the AC is again rectified to DC. To keep output voltage constant, the power supply needs a sophisticated feedback controller to monitor current draw by the load.

Modern switched-mode power supplies often include additional safety features such as the crowbar circuit to help protect the device and the user from harm. In the event that an abnormal high current power draw is detected, the switched-mode supply can assume this is a direct short and will shut itself down before damage is done. For decades PC computer power supplies have also provided a power good signal to the motherboard which prevents operation when abnormal supply voltages are present.

Switched mode power supplies have an absolute limit on their minimum current output. They are only able to output above a certain power level and cannot function below that point. In a no-load condition the frequency of the power slicing circuit increases to great speed, causing the isolation transformer to act as a tesla coil, causing damage due to the resulting very high voltage power spikes. Switched-mode supplies with protection circuits may briefly turn on but then shut down when no load has been detected. A very small low-power dummy load such as a ceramic power resistor or 10 watt light bulb can be attached to the supply to allow it to run with no primary load attached.

Power factor has become a recent issue of concern for computer manufacturers. Switched mode power supplies have traditionally been a source of power line harmonics and have a very poor power factor. Many computer power supplies built in the last few years now include power factor correction built right into the switched-mode supply, and may advertise the fact that they offer 1.0 power factor.

By slicing up the sinusoidal AC wave into very small discrete pieces, the portion of the alternating current not used stays in the power line as very small spikes of power that cannot be utilized by AC motors and results in waste heating of power line transformers. Hundreds of switched mode power supplies in a building can result in poor power quality for other customers surrounding that building, and high electric bills for the company if they are billed according to their power factor in addition to the actual power used. Filtering capacitor banks may be needed on the building power mains to suppress and absorb these negative power factor effects.


A computer's switched mode power supply unit



Programmable power supply
Programmable power supplies are those in which the output voltage can be varied remotely. One possible option is digital control by a computer interface. Variable properties include voltage, current, and frequency. This type of supply is composed of a processor, voltage/current programming circuits, current shunt, and voltage/current read-back circuits.

Programmable power supplies can furnish DC, AC, or both types of output. The AC output can be either single-phase or three-phase. Single-phase is generally used for low-voltage, while three-phase is more common for high-voltage power supplies.

When choosing a programmable power supply, several specifications should be considered. For AC supplies, output voltage, voltage accuracy, output frequency, and output current are important attributes. For DC supplies, output voltage, voltage accuracy, current, and power are important characteristics. Many special features are also available, including computer interface, overcurrent protection, overvoltage protection, short circuit protection, and temperature compensation. Programmable power supplies also come in a variety of forms. Some of those are modular, board-mounted, wall-mounted, floor-mounted or bench top.

Programmable power supplies are now used in many applications. Some examples include automated equipment testing, crystal growth monitoring, and differential thermal analysis

Uninterruptible power supply
An Uninterruptible Power Supply (UPS) takes its power from two or more sources simultaneously. It is usually powered directly from the AC mains, while simultaneously charging a storage battery. Should there be a dropout or failure of the mains, the battery instantly takes over so that the load never experiences an interruption. Such a scheme can supply power as long as the battery charge suffices, e.g., in a computer installation, giving the operator sufficient time to effect an orderly system shutdown without loss of data. Other UPS schemes may use an internal combustion engine or turbine to continuously supply power to a system in parallel with power coming from the AC mains. The engine-driven generators would normally be idling, but could come to full power in a matter of a few seconds in order to keep vital equipment running without interruption. Such a scheme might be found in hospitals or telephone central offices.

High-voltage power supply
High voltage refers to an output on the order of hundreds or thousands of volts. High-voltage power supplies use a linear setup to produce an output voltage in this range.

When choosing a high-voltage power supply, there are several options to consider. Some of these are maximum current, maximum power, maximum voltage, output polarity, user interface, and style. The first four of these characteristics of course depend upon the supply's intended application. There are many available types of user interfaces. For example, the interface may be local in the form of a digital meter, or analog meter. Also, the interface can be remote, as in a computer connection. Numerous styles of high-voltage power supplies are also manufactured. Available models come in printed circuit board mount, open frame (as designed to be incorporated into an instrument), and rack mount. Models with multiple outputs can also be found

Voltage multipliers
Voltage multipliers, as the name implies, are circuits designed to multiply the input voltage. The input voltage may be doubled (voltage doubler), tripled (voltage tripler), quadrupled (voltage quadrupler), etc. Voltage multipliers are also power converters. An AC input is converted to a higher DC output. These circuits allow high voltages to be obtained using a much lower voltage AC source.

Typically, voltage multipliers are composed of half-wave rectifiers, capacitors, and diodes. For example, a voltage tripler consists of three half-wave rectifiers, three capacitors, and three diodes. Full-wave rectifiers may be used in a different configuration to achieve even higher voltages. Also, both parallel and series configurations are available. For parallel multipliers, a higher voltage rating is required at each consecutive multiplication stage, but less capacitance is required. The voltage capability of the capacitor limits the maximum output voltage.

Voltage multipliers have many applications. For example, voltage multipliers can be found in everyday items like televisions and photocopiers. Even more applications can be found in the laboratory, such as cathode ray tubes, oscilloscopes, and photomultiplier tubes.

A modern computer power supply is a switched-mode supply designed to convert 110-240 V AC power from the mains supply, to several output both positive (and historically negative) DC voltages in the range + 12V,-12V,+5V,+5VBs and +3.3V. The first generation of computers power supplies were linear devices, but as cost became a driving factor, and weight became important, switched mode supplies are almost universal.

The diverse collection of output voltages also have widely varying current draw requirements, which are difficult to all be supplied from the same switched-mode source. Consequently most modern computer power supplies actually consist of several different switched mode supplies, each producing just one voltage component and each able to vary its output based on component power requirements, and all are linked together to shut down as a group in the event of a fault condition.

The most common modern computer power supplies are built to conform to the ATX form factor. The power rating of a PC power supply is not officially certified and is self-claimed by each manufacturer.A common way to reach the power figure for PC PSUs is by adding the power available on each rail, which will not give a true power figure. The more reputable makers advertise "True Wattage Rated" to give consumers the idea that they can trust the power advertised.


AC adapter
A linear or switched-mode power supply (or in some cases just a transformer) that is built into the top of a plug is known as a "wall wart", "power brick", "plug pack", "plug-in adapter", "adapter block", "domestic mains adapter" or just "power adapter". They are even more diverse than their names; often with either the same kind of DC plug offering different voltage or polarity, or a different plug offering the same voltage. "Universal" adapters attempt to replace missing or damaged ones, using multiple plugs and selectors for different voltages and polarities. Replacement power supplies must match the voltage of, and supply at least as much current as, the original power supply.

The least expensive AC units consist solely of a small transformer, while DC adapters include a few additional diodes. Whether or not a load is connected to the power adapter, the transformer has a magnetic field continuously present and normally cannot be completely turned off unless unplugged.

Because they consume standby power, they are sometimes known as "electricity vampires" and may be plugged into a power strip to allow turning them off. Expensive switched-mode power supplies can cut off leaky electrolyte-capacitors, use powerless MOSFETs, and reduce their working frequency to get a gulp of energy once in a while to power, for example, a clock, which would otherwise need a battery.

This type of power supply is popular among manufacturers of low cost electrical items because:

Switched mode mobile phone charger


1.Devices sold in the global marketplace don't need to be individually configured for 120 volt or 230 volt operation, just sold with the appropriate AC adapter.
2.The device itself doesn't need to be tested for compliance with electrical safety regulations. Only the adapter needs to be tested.
3.Product development becomes faster and cheaper, because the heat produced by the power supply is outside of the product.
4.The device itself can be smaller and lighter, since it does not contain the power supply.

SOME POWER SUPPLIES OF COMPUTERS

19 ) " KIA " WORLD WIDE CARZ

Kia Motors, a subsidiary of Hyundai Kia Automotive Group, is South Korea's 2nd largest automobile manufacturer with headquarters in Seoul, South Korea. Its CEO is Chung Eui-sun. The American arm is Kia Motors America. On October 20, 2006, Kia Motors America formally hosted a groundbreaking ceremony for its first US assembly plant in West Point, Georgia, at an initial cost of over $1 billion. Since 2005, Kia has started to focus on the European market and is currently the UK's fastest growing car company and had various other successes in the European market.



History



According to Kia Motors, the name "Kia" derives from the Sino-Korean words ki ("to come out") and a (which stands for Asia), it is roughly translated as arise or come up out of Asia or rising out of Asia.

South Korea's oldest car company, Kia was founded in 1944 as manufacturer of steel tubing and bicycles. In 1952, Kia changed its name from Kyungsung Precision Industry, and later built motorcycles, trucks and cars. Starting in 1986, in partnership with Ford, Kia produced several Mazda derived vehicles for both domestic sales in South Korea and exports into other countries. These models include the Pride (based on the Mazda 121) and Avella, which were sold in North America and Australasia as the Ford Festiva and Ford Aspire.

In 1992, Kia Motors America was incorporated in the United States. The first Kia-branded vehicles in the United States were sold from four dealerships in Portland, Oregon in February 1994. Since then, Kia expanded methodically one region at a time. Dealers in 1994 sold the Sephia, and a few years later the United States line expanded with the addition of the Sportage.

However, Kia's bankruptcy in 1997, part of the Asian financial crisis, resulted in the company being acquired in 1998 by South Korean rival Hyundai Motor Company, outbidding Ford Motor Company which had owned an interest in Kia Motors since 1986.


Kia Motors America


Kia Motors America (KMA) is the sales, marketing and distribution arm of Kia Motors Corporation based in Seoul, South Korea. KMA offers a complete line of vehicles through more than 640 dealers throughout the United States. For 2008, KMA recorded its 14th consecutive year of increased U.S. market share.


Kia Motors Europe




Kia Motors Europe (KME) is the European sales and marketing division of Kia Motors Corporation (KMC). In 2007 KME moved from its previous location at Hauptstrasse 185, Eschborn, Frankfurt to a new purpose built facility adjacent to the Messe in Frankfurt city centre.

From 1995 to 1999 Kia produced left and right hand drive versions of the Sportage SUV at the Karmann factory in Germany. From 1999 until production of the model ceased in 2003, all Sportage production reverted to South Korea.

Kia began importing cars to Europe in early 1991, initially selling just the Pride mini-car. It initially proved popular with buyers but sales fell towards the end of the decade and the end of production was finally announced in May 2000, with its successor — the Rio — not going on sale for another year.

The European range expanded in 1994 when Kia began importing the larger Mentor, a range of medium sized hatchbacks and saloon which were marketed as cheap and well-equipped alternatives to the likes of the Ford Escort and Vauxhall/Opel Astra. A facelift in 1999 saw the Mentor name retained for the saloon, but the hatchback was renamed Shuma. These models remained on sale until 2004, when the newer Cerato was launched and gave Kia one of its first serious competitors for mainstream brands.

The Sportage SUV range has been popular across Europe, but since 2002 Kia has gained more sales in this market thanks to the launch of the larger Sorento.

Kia did not enter Europe's large family car market until the launch of its Credos four-door saloon in 1999. This car was similar in size to the Ford Mondeo, but on its launch was actually cheaper to buy than the smaller Focus. It had a spacious interior, large boot, competitive asking price and high equipment levels, but it had little more appeal to sway buyers away from established European brands like Ford Motor Company, Vauxhall/Opel, Renault and Peugeot. Its successor, the Magentis, launched in 2001, was still nowhere near as popular as Kia might have hoped it would be.

Kia entered the MPV market in 1999 with the Sedona. On its launch, it was the cheapest full-size people carrier on sale in the United Kingdom.

2004 saw the commencement of European imports for the Kia Picanto city car. It has proved very popular with budget buyers in most of Europe.

As of 2007, Kia has been importing cars to Europe for 16 years. On its arrival, just one model was being sold. The range has gradually expanded over that time so the marque has a competitor in just about every sector except for the luxury and sports market. Sales of its products have so far failed to match those of established European brands, but current sales records have been impressive for a marque which only arrived in Europe at the start of the previous decade.



Kia Defense



Kia Motors has specialized in the production of military vehicles with variants and other transportation equipment and by supplying them as a sole maker of military vehicles designated by the South Korean Government since 1976, when Kia Heavy Industry Co., Ltd was established. Kia is currently designing an Kaiser Jeep M715-type vehicle named the KM450 for the South Korean Army on license from the U.S. Government. KIA Defense produces six vehicles:

KM42 half ton to three quarter ton variants of the M715

KM-45 modern variant of the M715

KM-25 variant of the M35 2-1/2 ton cargo truck

KM-50 variant of the M809 Truck both as 5 ton and 7 ton variants

KM-100 8x8 heavy tactical truck

K53 similar to the Swedish BV amphibious tracked vehicle

MODELS


KIA Morning/Picanto



The Kia Morning', known as the Kia Picanto in export markets (except in Chile, where it is badged with its original name and Taiwan where it is known as the Kia EuroStar), Kia New Morning in Vietnam and the Naza Suria in Malaysia, is a low cost city car produced in South Korea by Kia Motors (internal model index SA).

The Morning/Picanto is based on a shortened platform of the Hyundai Getz. It is available with either 1.0 or 1.1 L petrol engines. A 3-cylinder diesel engine (based on the Kia Cerato's 1.5 CRD four-cylinder unit), with direct injection and a variable geometry turbocharger, has been available in the European market since Spring 04, with power reaching 75 PS (55 kW). The Morning is 3,495 mm (137.6 in) long with a five-door hatchback body. Automatic gearboxes are optional in the petrol units.



KIA cee'd



The Kia cee'd is a small family car released in the European market by the Korean manufacturer Kia Motors in December 2006. It is available as a five-door hatchback, three-door hatchback ("pro_cee'd"), and five-door estate ("cee'd SW"), with a choice of up to five engines (three petrol and two diesel), four trim levels (S, GS, LS, SR) and either manual or automatic transmissions — and is sold in over 20 variants of the above in some markets. Kia used the Paris Motor Show 2006 to preview a five-door estate variant in production form, and a three-door concept, both of which were to be on sale from Autumn 2007, combining with the five door hatchback model to give a model range of over 50 variants in some markets. The Hyundai i30 shares the platform with cee'd.



KIA Rio



The Kia Rio is a subcompact car produced by the South Korean automaker Kia Motors and introduced in August 2000 for the 2001 model year. In the company's lineup, it replaced the smaller Kia Pride, which ceased production in 2000.




KIA Spectra



The Kia Spectra or Kia Cerato is a compact car / small family car produced by the Korean automaker Kia Motors since 2000, originally sold only as a hatchback. When the car was redesigned in 2004-05, it later became Kia's top-selling vehicle in the United States, which it remains.



KIA Optima



The Kia Optima/Magentis is a mid-size four-door sedan manufactured by Kia Motors and marketed globally through two generations and various nameplates.

The car has been marketed as the Lotze in South Korea, and as the Optima in the United States since 2001, the Magentis Australia since 2001, and Europe since 2002. In Chile the first generation was marketed as Optima, and since as Magentis. In Canada it is marketed as the Magentis.

The Optima is produced for the Chinese market by the Dongfeng Yueda Kia Automobile Company, a joint venture with Kia.




KIA Opirus



The Kia Opirus (known as Amanti in North America) is a full-size luxury car / executive car produced by Kia Motors of South Korea that was launched in April 2003. The Opirus/Amanti was Kia's first entry into the large-car market. It is sold in a single trim level and only as a sedan, and has an MSRP of US$26,875. It shares some components with its now-defunct corporate cousin, the Hyundai XG Grandeur, including its 3.5 L V6 engine.



KIA Soul



The Kia Soul is a subcompact, mini MPV produced in South Korea for the global market. It was designed at Kia's design center in California, and unveiled at the 2008 Paris Motor Show. Production began in late 2008, with the first vehicles appearing at European dealerships in February 2009 and North American dealerships in March 2009, as a 2010 model.



KIA Carens



The Kia Carens is a compact MPV launched in 1999 by the Korean manufacturer Kia. It was discontinued in Australia in 2001, but production continued elsewhere for a new model which was launched in 2003. In 2006 a new Carens has been presented as a 2007 model year. The Carens/Rondo is slotted below the Kia Carnival/Sedona in Kia's minivan lineup.

18 ) HISTORY OF ENGINEERING

BEFORE SCIENTIFIC REVOLUTION

The forerunners of engineers, practical artists and craftsmen, proceeded mainly by trial and error. Yet tinkering combined with imagination produced many marvelous devices. Many ancient monuments cannot fail to incite admiration. The admiration is embodied in the name “engineer” itself. It originated in the eleventh century from the Latin ingeniator, meaning one with ingenium, the ingenious one. The name, used for builders of ingenious fortifications or makers of ingenious devices, was closely related to the notion of ingenuity, which was captured in the old meaning of “engine” until the word was taken over by steam engines and its like. Leonardo da Vinci bore the official title of Ingegnere Generale. His notebooks reveal that some Renaissance engineers began to ask systematically what works and why.

DURING INDUSTRIAL REVOLUTION

The first phase of modern engineering emerged in the Scientific Revolution. Galileo’s Two New Sciences, which seeks systematic explanations and adopts a scientific approach to practical problems, is a landmark regarded by many engineer historians as the beginning of structural analysis, the mathematical representation and design of building structures. This phase of engineering lasted through the First Industrial Revolution, when machines, increasingly powered by steam engines, started to replace muscles in most production. While pulling off the revolution, traditional artisans transformed themselves to modern professionals. The French, more rationalistic oriented, spearheaded civil engineering with emphasis on mathematics and developed university engineering education under the sponsorship of their government. The British, more empirically oriented, pioneered mechanical engineering and autonomous professional societies under the laissez-faire attitude of their government. Gradually, practical thinking became scientific in addition to intuitive, as engineers developed mathematical analysis and controlled experiments. Technical training shifted from apprenticeship to university education. Information flowed more quickly in organized meetings and journal publications as professional societies emerged.

2ND INDUSTRIAL REVOLUTION

The second industrial revolution, symbolized by the advent of electricity and mass production, was driven by many branches of engineering. Chemical and electrical engineering developed in close collaboration with chemistry and physics and played vital roles in the rise of chemical, electrical, and telecommunication industries. Marine engineers tamed the peril of ocean exploration. Aeronautic engineers turned the ancient dream of flight into a travel convenience for ordinary people. Control engineers accelerated the pace of automation. Industrial engineers designed and managed mass production and distribution systems.



ENGINEERING IN INFORMATION AGE

Research and development boomed in all fields of science and technology after World War II, partly because of the Cold War and the Sputnik effect. The explosion of engineering research, which used to lagged behind natural science, was especially impressive, as can be seen from the relative expansion of graduate education. Engineering was also stimulated by new technologies, notably aerospace, microelectronics, computers, novel means of telecommunications from the Internet to cell phones. Turbojet and rocket engines propelled aeronautic engineering into unprecedented height and spawned astronautic engineering. Utilization of atomic and nuclear power brought nuclear engineering. Advanced materials with performance hitherto undreamed of poured out from the laboratories of materials science and engineering. Above all, microelectronics, telecommunications, and computer engineering joined force to precipitate the information revolution in which intellectual chores are increasingly alleviated by machines.

The American Engineers' Council for Professional Development (ECPD, the predecessor of ABET) has defined engineering as follows:

“[T]he creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under specific operating conditions; all as respects an intended function, economics of operation and safety to life and property"

To lead the progress of these sophisticated technologies, engineers have remade themselves by reforming educational programs and expanding research efforts. Intensive engineering research produced not only new technologies but also bodies of powerful systematic knowledge: the engineering sciences and systems theories in information, computer, control, and communications. Engineering developed extensive theories of its own and firmly established itself as a science of creating, explaining, and utilizing manmade systems. This period also saw the maturation of graduate engineering education and the rise of large-scale research and development organized on the national level.

Later, as the design of civilian structures such as bridges and buildings matured as a technical discipline, the term civil engineering entered the lexicon as a way to distinguish between those specializing in the construction of such non-military projects and those involved in the older discipline of military engineering (the original meaning of the word “engineering,” now largely obsolete, with notable exceptions that have survived to the present day such as military engineering corps, e.g., the U.S. Army Corps of Engineers). Since that time engineering was a relevant use of knowlege, the knowledge than reflected on the user. which was examined by Adem A(Which was an chemistry student which went to Scotts when he was a child.

The concept of engineering has existed since ancient times as humans devised fundamental inventions such as the pulley, lever, and wheel. Each of these inventions is consistent with the modern definition of engineering, exploiting basic mechanical principles to develop useful tools and objects.

So far the physical sciences – physics and chemistry – have contributed most to technology. They will continue to contribute, for instance in the emerging nanotechnology that will take over the torch of the microelectronics revolution. Increasingly, they are joined by biology, which has been transformed by the spectacular success of molecular and genetic biology. Biotechnology is a multidisciplinary field, drawing knowledge from biology, biochemistry, physics, information processing and various engineering expertise. The cooperation and convergence of traditional intellectual disciplines in the development of new technology is the trend of the future.

17 ) ELECTRONICS DIGITAL ENGINEERING CIRCUITS

Digital circuits are electric circuits based on a number of discrete voltage levels. Digital circuits are the most common physical representation of Boolean algebra and are the basis of all digital computers. To most engineers, the terms "digital circuit", "digital system" and "logic" are interchangeable in the context of digital circuits. Most digital circuits use two voltage levels labeled "Low"(0) and "High"(1). Often "Low" will be near zero volts and "High" will be at a higher level depending on the supply voltage in use. Ternary (with three states) logic has been studied, and some prototype computers made.

Computers, electronic clocks, and programmable logic controllers (used to control industrial processes) are constructed of digital circuits. Digital Signal Processors are another example.

Building-blocks:

Logic gates
Adders
Binary Multipliers
Flip-Flops
Counters
Registers
Multiplexers
Schmitt triggers



1- Logic gate
A logic gate performs a logical operation on one or more logic inputs and produces a single logic output. The logic normally performed is Boolean logic and is most commonly found in digital circuits. Logic gates are primarily implemented electronically using diodes or transistors, but can also be constructed using electromagnetic relays, fluidics, optics, molecules, or even mechanical elements.

In electronic logic, a logic level is represented by a voltage or current, (which depends on the type of electronic logic in use). Each logic gate requires power so that it can source and sink currents to achieve the correct output voltage. In logic circuit diagrams the power is not shown, but in a full electronic schematic, power connections are required.



2- Adder
In electronics, an adder or summer is a digital circuit that performs addition of numbers. In modern computers adders reside in the arithmetic logic unit (ALU) where other operations are performed. Although adders can be constructed for many numerical representations, such as Binary-coded decimal or excess-3, the most common adders operate on binary numbers. In cases where twos complement or ones complement is being used to represent negative numbers, it is trivial to modify an adder into an adder-subtracter. Other signed number representations require a more complex adder.


3- Binary multiplier
A binary multiplier is a electronic circuit used in digital electronics, such as a computer, to multiply two binary numbers. It is built using binary adders.



4- Flip-flop
In digital circuits, a flip-flop is a term referring to an electronic circuit (a bistable multivibrator) that has two stable states and thereby is capable of serving as one bit of memory. Today, the term flip-flop has come to mostly denote non-transparent (clocked or edge-triggered) devices, while the simpler transparent ones are often referred to as latches; however, as this distinction is quite new, the two words are sometimes used interchangeably (see history).

A flip-flop is usually controlled by one or two control signals and/or a gate or clock signal. The output often includes the complement as well as the normal output. As flip-flops are implemented electronically, they require power and ground connections.



5- Counter
In digital logic and computing, a counter is a device which stores (and sometimes displays) the number of times a particular event or process has occurred, often in relationship to a clock signal. In practice, there are two types of counters:

up counters, which increase (increment) in value
down counters, which decrease (decrement) in value


6- Processor register
In computer architecture, a processor register is a small amount of storage available on the CPU whose contents can be accessed more quickly than storage available elsewhere. Most, but not all, modern computer architectures operate on the principle of moving data from main memory into registers, operating on them, then moving the result back into main memory—a so-called load-store architecture. A common property of computer programs is locality of reference: the same values are often accessed repeatedly; and holding these frequently used values in registers improves program execution performance.

Processor registers are at the top of the memory hierarchy, and provide the fastest way for a CPU to access data. The term is often used to refer only to the group of registers that are directly encoded as part of an instruction, as defined by the instruction set. More properly, these are called the "architectural registers". For instance, the x86 instruction set defines a set of eight 32-bit registers, but a CPU that implements the x86 instruction set will often contain many more registers than just these eight.

Allocating frequently used variables to registers can be critical to a program's performance. This action, namely register allocation is performed by a compiler in the code generation phase.



7- Multiplexer
In electronics, a multiplexer or mux (occasionally the term muldex or muldem[1] is also found, for a combination multiplexer-demultiplexer) is a device that performs multiplexing; it selects one of many analog or digital input signals and forwards the selected input into a single line. A multiplexer of 2n inputs has n select bits, which are used to select which input line to send to the output.

An electronic multiplexer makes it possible for several signals to share one device or resource, for example one A/D converter or one communication line, instead of having one device per input signal.

In electronics, a demultiplexer (or demux) is a device taking a single input signal and selecting one of many data-output-lines, which is connected to the single input. A multiplexer is often used with a complementary demultiplexer on the receiving end.

An electronic multiplexer can be considered as a multiple-input, single-output switch, and a demultiplexer as a single-input, multiple-output switch. The schematic symbol for a multiplexer is an isosceles trapezoid with the longer parallel side containing the input pins and the short parallel side containing the output pin. The schematic on the right shows a 2-to-1 multiplexer on the left and an equivalent switch on the right. The sel wire connects the desired input to the output.



8- Schmitt trigger
In electronics, a Schmitt trigger is a comparator circuit that incorporates positive feedback.

When the input is higher than a certain chosen threshold, the output is high; when the input is below another (lower) chosen threshold, the output is low; when the input is between the two, the output retains its value. The trigger is so named because the output retains its value until the input changes sufficiently to trigger a change. This dual threshold action is called hysteresis, and implies that the Schmitt trigger has some memory.

The benefit of a Schmitt trigger over a circuit with only a single input threshold is greater stability (noise immunity). With only one input threshold, a noisy input signal near that threshold could cause the output to switch rapidly back and forth from noise alone. A noisy Schmitt Trigger input signal near one threshold can cause only one switch in output value, after which it would have to move beyond the other threshold in order to cause another switch.