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A typical solar panel

Solar energy is comes from the sun.

Solar energy can be classified in two different ways.

1- One way is through photovoltaic conversion.
2- Second way is through solar thermal conversion.


During photovoltaic conversion, solar energy is collected through panels, called solar panels. Solar panels are covered with large modules which are covered with lots of little PV cells, or photovoltaic cells. The PV cells collect the light from the sun. Once the light is inside a PV cell, there is a semiconductor made of a thin sheet of silicone crystal which takes in the photons from the sunlight. A photon is a particle of solar energy.

Within the semiconductor, energy of the photons shifts to the electrons. This energizes the electrons. Then the electrons break out of the semiconductor to get to the silicone atoms. Then they flow into the electric current. Usually a solar cell is made of a glass protective layer, an anti-reflective coat, and electric contacts.
We use PV cell systems every day. Common tools like watches and calculators are powered with PV systems. Look at the top of a calculator. Do you see the little squares at the top? Those are lots of little PV cells. Usually PV cells don’t generate much electricity. PV cells generate about ½ a volt per square decimeter. A solar panel making fifty watts of electricity is about four decimeters by ten decimeters. What if you don’t know how much energy your appliance or machine needs? Well, the answer is easy. Find out the maximum amount of watts the appliance or machine needs and multiply that by the number of hours each day it is averagely used. The answer is "the number you come up with" watt-hours. To explain it more, let’s say my microwave oven uses a maximum of 2000 watts and it is used ½ an hour each day. 2000 multiplied by ½ an hour equals 1000, so I need my PV system (my solar panels) to supply 1000 watt-hours for that microwave oven. Since I need to be ready for a crash or a change of appliance, I should really have my solar panels supply about 2000 watt-hours
Well, more about a PV cell system. Most PV cells are grouped together in arrays. Second, groups of PV cells generate a DC or direct current. That is the kind of electricity made by batteries. Some appliances and other machines like microwave ovens use AC, or alternating current, so inverters are used to change the DC into an AC.
Another type of solar energy is solar thermal conversion. In this process, there are thermal conversion panels (panels that absorb heat) which are grouped together often in a dish or trough system. The solar energy is then absorbed and concentrated into a line or a point that heats a pipe filled with fluid. These systems can concentrate the intensity of sunlight up to 10,000 times of normal sunlight.
Many people use a solar heating system to heat their house. This type of system is more effective than using a PV system to heat homes or water. You can tell the difference because solar heaters can turn 60% of the sun's energy into heat whereas PV systems can only change 12% to 15%. Solar heaters are able to heat large things like pools, water, and houses. So as you can see, when it’s heating, you are better off using a solar heater

Posted by Kami Tuesday, April 29, 2008 0 comments


The Cell Phone Network.
A cellular network is a radio network made up of a number of radio cells (or just cells) each served by a fixed transmitter, known as a cell site or base station. These cells are used to cover different areas in order to provide radio coverage over a wider area than the area of one cell. Cellular networks are inherently asymmetric with a set of fixed main transceivers each serving a cell and a set of distributed (generally, but not always, mobile) transceivers which provide services to the network's users.

Cellular networks offer a number of advantages over alternative solutions:

increased capacity
reduced power usage
better coverage
A good (and simple) example of a cellular system is an old taxi driver's radio system where the taxi company will have several transmitters based around a city each operated by an individual operator.

Posted by Kami Sunday, April 27, 2008 0 comments

ALTERNATE ENERGY
The demand of energy of the world is growing day by day. On other hand the supply of the fuel I may say the Black Gold is slightly decreasing. For this reason the prices of the fuel / oil are touching the highest levels. It is also becoming difficult to afford the owned vehicles to put on road.
And to keep the oil based power houses operational because as the generation cost raised the profit decreases and it became burden to end users which is always happens. In my opinion the solution for all aforesaid problems only to produce Alternate Energy which may be through?
1. WIND
2. SOLAR
3. GEOTHERMAL
4. SAFE NUCLEAR
5. BIO GASS ENERGY

Through above mentioned all alternate ways we can produce a cheap envoinent friendly energy .which will not only be fruitful to us but also for our next generations at all. One point I would like to discuss that the initial coast will not less to set any alternate system to produce the energy .But once Any alternate system established it will be one time investment and shall pay forever.
The option to adopt a specified alternate way / system depends upon the geographic conditions of any jurisdiction. The area where the sun remain rise for a long time of the day can opt SOLAR ENERGY. Likewise the area where the wind blow and can drive the wind mile there will be positive possibility to install wind gen system.
The nuclear energy can also set up if the safety measures are observed up to the mark Hydel Power generation is also a cheap way to produce the energy and it also help to irrigate the fields.

Posted by Kami Thursday, April 24, 2008 0 comments


In electrical engineering distribution is very typical field all the power a system generates and all the power a system transmittes will be un usefull if their is not a reliable Power Distribution System.

It is also diversified in high voltage and low voltage distribution system.
The low voltage is the most use full source for any domestic or a light load commercial purposes and the all the electric utilities companies got their revenue and profit through the low voltage power distribution system. In the Picture below you can see the low voltage power distribution control and safety system designed by the Siemens.

Posted by Kami Wednesday, April 23, 2008 0 comments


The basic circuit breaker consists of a simple switch, connected to either a bimetallic strip or an electromagnet. The diagram above shows a typical electromagnet design.


The electricity magnetizes the electromagnet. Increasing current boosts the electromagnet's magnetic force, and decreasing current lowers the magnetism. When the current jumps to unsafe levels, the electromagnet is strong enough to pull down a metal lever connected to the switch linkage. The entire linkage shifts, tilting the moving contact away from the stationary contact to break the circuit. The electricity shuts off.

A bimetallic strip design works on the same principle, except that instead of energizing an electromagnet, the high current bends a thin strip to move the linkage. Some circuit breakers use an explosive charge to throw the switch. When current rises above a certain level, it ignites explosive material, which drives a piston to open the switch

Posted by Kami Monday, April 21, 2008 0 comments


Fundamentals of stepper motor drive technology
Classic and inexpensive: Drives with stepper motorsStepper motors are ideal for applications where cost optimisation is more important than speed and dynamism.
High-end axis controller SPC 200The SPC 200 can control up to 4 pneumatic or electrical axes. One of the main development criteria was ease of use:
Record selection: for positioning tasks with fixed traversing movements which can simply be called up via I/Os.
Program mode: with up to 100 programs for solving the most complex tasks or calculating and changing positions; I/Os control the process
Quick commissioning using the WINPISA diagnostic and programming tool
The PROFIBUS fieldbus interface facilitates direct reading and writing of the position data. You can calculate, select and archive the position in a PLC and then download it directly into the SPC200. A functional module for the Siemens S7 controller family provides assistance.

Posted by Kami Saturday, April 19, 2008 0 comments

The Basics
A typical analog camcorder contains two basic parts:
A camera section, consisting of a CCD, lens and motors to handle the zoom, focus and aperture
A VCR section, in which a typical TV VCR is shrunk down to fit in a much smaller space.
The camera component's function is to receive visual information and interpret it as an electronic video signal. The VCR component is exactly like the VCR connected to your television: It receives an electronic video signal and records it on video tape as magnetic patterns (see How VCRs Work for details).
These two sections are easily seen in the following photos.

Posted by Kami Monday, April 14, 2008 0 comments

In most of the world, camcorders, or video camera-recorders, have been a familiar sight for nearly 20 years. People take them everywhere: to school plays, sports events, family reunions and even births! When you go to a popular tourist spot, you are surrounded by them. Camcorders have really taken hold in the United States, Japan and many other countries around the world because they are an extremely useful piece of technology that you can own for under $300 (or more than $100,000).
How can such a small device do so much? Particularly for anyone born before the 1980s, it's simply amazing that quality video cameras are now readily available as consumer items, and that they're so easy to use. In this article, we'll look inside these extremely popular devices to find out what exactly is going on. We'll explore traditional analog camcorders and also look at the technology used in digital camcorders.

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Oscillators are important in many different types of electronic equipment. For example, a quartz watch uses a quartz oscillator to keep track of what time it is. An AM radio transmitter uses an oscillator to create the carrier wave for the station, and an AM radio receiver uses a special form of oscillator called a resonator to tune in a station. There are oscillators in computers, metal detectors and even stun guns.
To understand how electronic oscillators work, it is helpful to look at examples from the physical world. In this article, you'll learn the basic idea behind oscillators and how they're used in electronics

Posted by Kami 0 comments

Electronic engineering is a discipline dealing with the behavior and effects of electrons (as in electron tubes and transistors) and with electronic devices, systems, or equipment. The term now also covers a large part of electrical engineering degree courses as studied at most European universities. In the U.S., however, electrical engineering implies all the wide electrical disciplines including electronics.
In many areas, electronic engineering is considered to be at the same level as electrical engineering, requiring that more general programmes be called electrical and electronic engineering (many UK universities have departments of Electronic and Electrical Engineering). Both define a broad field that encompasses many subfields including those that deal with power, instrumentation engineering, telecommunications, and semiconductor circuit design amongst many others

Posted by Kami 0 comments

Information Communication Technology (ICT) has been largely limited either for peer to peer communication, or expert to audience communication. In peer to peer communication I would include exchanging information electronically, say e-mail. In the second category I would include information through books, newspapers, magazines and websites whether maintained by commercial establishments, government agencies or educational institutions. The information transfer by this mode was largely one-way, from the expert to the targeted audience. The targeted audience has had no choice but to accept the information as it is presented. Because the person(s) responsible for creating information was not totally aware of the capabilities, likes, limitations of the targeted audience. For example, even when a fraction of the targeted population was not really be comfortable with language in which the information is presented she had no alternative. Same was the case even when the targeted person did know a particular language s/he may be hampered by the dialect. The information was usually presented as text only even though the target may not be always comfortable in reading text. In short, the technologies often used to fall short of the real requirements of information recipient. Thus there was a huge potential for the developing ICTs that will suit the pockets, tastes and real requirements of a burgeoning population of information seekers.
Till a decade ago, the Internet that was a vehicle to disseminate information from a selected few to the rather affluent sections of the society was mistakenly viewed as the technology for the future of communication. But in the last few years the indicators point to changes that may yet again revolutionize information communication.

Posted by Kami 0 comments

THIS PAGE IS UNDER CONSTRUCTION
Aerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space. Aerospace is a very diverse field, with a multitude of commercial, industrial and military applications.
Aerospace is not the same as airspace, which is a term used to describe the physical air space directly above a location on the ground.

Posted by Kami 0 comments



Power System Engineering deals with the generation, transmission and distribution of electricity as well as the design of a range of related devices. These include transformers, electric generators, electric motors, high voltage engineering and power electronics. In many regions of the world, governments maintain an electrical network called a power grid that connects a variety of generators together with users of their energy. Users purchase electrical energy from the grid, avoiding the costly exercise of having to generate their own. Power engineers may work on the design and maintenance of the power grid as well as the power systems that connect to it. Such systems are called on-grid power systems and may supply the grid with additional power, draw power from the grid or do both. Power engineers may also work on systems that do not connect to the grid, called off-grid power systems, which in some cases are preferable to on-grid systems. The future includes Satellite controlled power systems, with feedback in real time to prevent power surges and prevent blackouts

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Electrical engineering sometimes referred to as electrical and electronic engineering is an engineering field that deals with the study and application of electricity, electronics and electromagnetism. The field first became an identifiable occupation in the late nineteenth century after commercialization of the electric telegraph and electrical power supply. The field now covers a range of sub-studies including power, electronics, control systems, signal processing and telecommunications.
Electrical engineering may or may not encompass electronic engineering. Where a distinction is made, usually outside of the United States, electrical engineering is considered to deal with the problems associated with large-scale electrical systems such as power transmission and motor control, whereas electronic engineering deals with the study of small-scale electronic systems including computers and integrated circuits.Another way of looking at the distinction is that electrical engineers are usually concerned with using electricity to transmit energy, while electronic engineers are concerned with using electricity to transmit information.

Posted by Kami 0 comments

Science, engineering and technology
The distinction between science, engineering and technology is not always clear. Science is the reasened investigation or study of phenomena, aimed at discovering enduring principles among elements of the phenomenal world by employing formal techniques such as the scientific method.Technologies are not usually exclusively products of science, because they have to satisfy requirements such as utility, usability and safety.
Engineering is the goal oriented process of designing and making tools and systems to exploit natural phenomena for practical human means, often (but not always) using results and techniques from science. The development of technology may draw upon many fields of knowledge, including scientific, engineering, mathematical, linguistic, and historical knowledge, to achieve some practical result.
Technology is often a consequence of science and engineering — although technology as a human activity precedes the two fields. For example, science might study the flow of electrons in electriacal conductors, by using already-existing tools and knowledge. This new-found knowledge may then be used by engineers to create new tools and machines, such as semiconductors, computers, and other forms of advanced technology. In this sense, scientists and engineers may both be considered technologists; the three fields are often considered as one for the purposes of research and reference.

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The secret to the SHARP's long flight time was a large, ground-based Long-distance Wireless PowerWhether or not it incorporates resonance, induction generally sends power over relatively short distances. But some plans for wireless power involve moving electricity over a span of miles. A few proposals even involve sending power to the Earth from space.
In the 1980s, Canada's Communications Research Centre created a small airplane that could run off power beamed from the Earth. The unmanned plane, called the Stationary High Altitude Relay Platform (SHARP), was designed as a communications relay. Rather flying from point to point, the SHARP could fly in circles two kilometers in diameter at an altitude of about 13 miles (21 kilometers). Most importantly, the aircraft could fly for months at a time.Long-distance Wireless PowerWhether or not it incorporates resonance, induction generally sends power over relatively short distances. But some plans for wireless power involve moving electricity over a span of miles. A few proposals even involve sending power to the earth from space.
In the 1980s, Canada's Communications Research Centre created a small airplane that could run off power beamed from the Earth. The unmanned plane, called the Stationary High Altitude Relay Platform (SHARP), was designed as a communications relay. Rather flying from point to point, the SHARP could fly in circles two kilometers in diameter at an altitude of about 13 miles (21 kilometers). Most importantly, the aircraft could fly for months at a time.microwave transmitter. The SHARP's circular flight path kept it in range of this transmitter. A large, disc-shaped rectifying antenna, or rectenna, just behind the plane's wings changed the microwave energy from the transmitter into direct-current (DC) electricity Because of the microwaves' interaction with the rectenna, the SHARP had a constant power supply as long as it was in range of a functioning microwave array

Posted by Kami Saturday, April 12, 2008 0 comments

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