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Saturday, October 27, 2012

GATE (EC) - Previous Year Questions



          Graduate Aptitude Test in Engineering (GATE) is an all India examination that primarily tests the comprehensive understanding of various undergraduate subjects in Engineering and Technology. The GATE score of a candidate reflects a relative performance of a candidate. The score is used for admissions to post-graduate engineering programmes (eg. M.E., M.Tech, direct Ph.D.) in Indian higher education institutes with financial assistance provided by MHRD and other Government agencies.  The score may also used by Public sector units for employment screening purposes.
        GATE is administered and conducted jointly by the Indian Institute of Science and seven Indian Institutes of Technology on behalf of the National Coordination Board (NCB) – GATE, Department of Higher Education, Ministry of Human Resource Development (MHRD), Government of India. The GATE Committee, which comprises of representatives from the administering institutes, is the sole authority for conducting the examination and declaring the results

To Download Previous year GATE (Electronics & Communication) Questions: click here

Monday, August 27, 2012

Every Engineer is a Green Engineer


BY JOHN R. PLATT

Yes, it's true, some American solar and wind-energy jobs have moved overseas  and more might follow — but there are still plenty of opportunities for engineers who want to be "green" or eco-friendly. In fact, being green might already be an essential part of your job no matter what industry you work in.
"I think every engineer needs to think green when they do their jobs," says Dave Arthur, CEO of SouthWest Nano Technologies in Norman, Okla., who says all engineers should constantly be aware of the need to produce things cheaper, more efficiently and with fewer emissions. Of course doing so means leaving behind a cleaner planet for our children and grandchildren, but Arthur says it's also part of the daily life of a modern engineer.
"We have responsibility to the environment as engineers. We also have a responsibility to our company to reduce costs," Arthur says. He disputes the conventional wisdom that producing greener products always costs more money. "I found it to be totally untrue. Really, the mindset's got to be that youcan have it all. Let's reduce costs and make this better for the environment."
Arthur says his company, which produces carbon nanotubes for printed electronics and other applications, expects to reduce its costs dramatically by greening its processes. "A lot of your costs are energy and raw materials consumption," he explains. Even though he says they currently have a good process, it won't be good enough in the future when the demand for new materials grows and production expands. "Greener manufacturing initiatives become very important as you scale your business, not just from a regulatory standpoint, but just from sheer cost. Right now, a kilogram of nanotubes that we make consumes 1,000 kilograms of chemicals. So if you want to make one ton of nanotubes, you would consume a thousand tons of chemicals and produce a thousand tons of CO2 emissions. That's becoming frightening."
Arthur says his company has developed techniques that will dramatically reduce that waste flow and, in the process, reduce emissions and costs. Implementing these green, cost-saving techniques will be essential to the success of their products. "You have many materials vying to become the standard in printed electronics, so it's very competitive," he says. "You can't stand pat. We are going to improve our quality many fold and reduce our costs tenfold over the next five years. Greener manufacturing initiatives are the primary way to do that."

Different Thinking Required
Making that transition may mean engineers need to challenge themselves to break past convention. Praerit Garg did that when he co-founded Symform, a cloud-computing storage and backup company in Seattle, Wash. Symform developed a peer-to-peer data storage network that does not employ an energy-hungry physical data center like most other online companies. Instead, Symform encrypts its users' data and stores it in fragments on other users' hard drives, a process that requires no dedicated data center and which uses significantly less energy. "Here was a solution where the economic argument and being green are actually completely aligned," Garg says.
But a distributed, decentralized approach doesn't come pre-built out of the box. It meant hiring engineers who wanted to solve a unique set of problems. "I find engineers are always intrigued by a different way of doing things," Garg says. "Those are the engineers we want in our company."
Engineers aren't the only ones who need to think differently. Arthur says the message of innovating and going green should come from the top. "It's a mindset in the leadership and management of the company that needs to drive that approach."
Unfortunately, many companies don't have that built in to their cultures, and that can lead to environmental consequences. "I think it's very easy for companies and businesses to take the easy way out," Garg says. "It takes time to develop an approach like ours. But in most economic models time is a very precious resource. Companies want to do the simpler thing, the quicker thing. Usually the easy way out is also wasteful."

Collaboration Makes Perfect
Developing new and green technologies isn't done in a vacuum. It requires collaboration between engineers from many different disciplines. For example, look at what is required to design a smart thermostat: "That takes an electrical engineer, a computer engineer, a mechanical engineer and possibly an industrial engineer, just for that one device," says Nathan Johnson, a postdoctoral fellow with the Nation Science Foundation and the American Society of Engineering Education who is researching micro-grid power system modeling at HOMER Energy LLC in Boulder, Colo. "If you want to make something that robust, it's going to take all of those different kinds of thinking," he says. Sometimes one person will be able to fill more than one of those roles, but more often than not design will involve a team of complementary skills and personalities.
Wind turbines are another example. "There's still a lot of research that is needed in terms of tower strength, increasing the robustness of the power curve, and generating power at low wind speeds," Johnson says. "That requires a team of mechanical, electrical and materials engineers."
Small wind turbines that can be mounted on buildings or put up to power individual homes require similar teams. "They're so closely intertwined that you can't separate them," says Mateo Chaskel, assistant vice president of operations at Urban Green Energy in New York City. Small wind is still an emerging technology and a young field, so the company often needs to conduct its own modeling rather than study published research. "We have to come up with our own simulations, hypotheses and testing methods, which is a new stage for a growing company," he says.
Sometimes collaboration means tapping into skills outside of a particular organization. "In our company, we mainly have chemical engineers, chemists and mechanical engineers," says Arthur. "However, we have several very significant collaborations with companies that have expertise higher up the value chain. We work hand in hand with their electronics engineers to make sure that our materials are being designed to meet the needs of their next-generation devices that they want to build."
While SouthWest NanoTechnologies does not employ any electrical engineers itself, Arthur says "We do encourage our people to become savvier about electronics so they can collaborate with our customers." "You can't have one engineer who knows absolutely zero about what the other engineer does. Engineers always have to work with other engineers. Having a little bit of common ground makes that a lot more practical."

The Invisible Green: Just Because You Can't See it, Doesn't Mean It's Not There
Opportunities for engineers to go green or develop more eco-friendly products and processes abound, but at this point they probably won't get the same amount of press as electric cars, photovoltaic cells or wind turbines. "It's not going to be in the headlines," Arthur says. Instead, green engineers will make products more efficient, reduce waste in production, figure out ways to produce fewer emissions, and maybe break a few old business models in the process. It might not be as well understood by the public as an electric car, but it will make a difference.

Friday, May 25, 2012

Improve Your Car’s Fuel Efficiency

Seeking measures to improve fuel economy is the only way to combat rising fuel prices. Do not disregard these simple guidelines; each little step can really start adding up to significant savings to your budget.

 
Do Fuel Quality/Types/Additives Help Mileage?
Petrol pump attendants often try to convince you to go for 'Speed petrol' or 'X-tra Mile diesel'. But this need not necessarily help improve your vehicle's fuel efficiency. Always use the grade recommended for the vehicle by the manufacturer. Higher octane fuel may not only be a waste of money but may harm the vehicle, as well. However sticking to one brand of fuel is always good for the engine.

Keep the Windows Closed
Driving with your windows open considerably reduces mileage, far more than keeping the AC on while driving along highways. So preferably keep the windows closed and the AC on if you want to keep cool. Of course the air-conditioning decreases fuel efficiency considerably, so use it judiciously. 

Refill in the morning/late evening
During these times petrol is densest. Keep in mind - fuel pumps measure volumes of petrol, not densities of fuel concentration. You are charged according to "volume of measurement". 
Keeping the tyres well inflated is one of the simplest things you can do to help improve your car's fuel efficiency. You can improve the mileage by about 3.3 percent if you keep your tyres inflated properly.

Lighten Your Load
Empty out your boot of unnecessary items. For every extra 45 kg you carry, your fuel efficiency can drop by 1-2% in a typical vehicle.


S-L-O-W D-O-W-N
The faster you drive, the more fuel you use. Driving within the speed limit recommended by the manufacturer helps save fuel. Driving just 5mph over the speed limit can affect fuel economy by up to 23%. Likewise, quick acceleration consumes too much fuel; accelerate slowly and gradually.


Tune Your Engine
A well-tuned engine can improve fuel economy by up to 4%. So change your oil and follow your car manufacturer's recommendation on servicing.

Clean the Air Filters Regularly
Air filters keep impurities from damaging your engine. Replacing a clogged air filter can improve fuel economy by as much as 10%.

Don't Be a Clutch-Driver
Never keep your foot on the clutch while driving. When you do this, pressure is being placed on your clutch, and it not only reduces mileage, but also wears out the clutch plate, replacing which is not cheap.

Keep the Car in Showroom Condition
It's always prudent to keep the car in the showroom condition. Remember that any modification to the car, such as broad tyres, diffusers etc., will adversely affect the mileage.

Saturday, March 31, 2012

Desert sun can power all of Africa’s needs



Nairobi: Solar power from Africa’s deserts could supply all 600 million citizens currently without electricity and even export power to Europe, a green energy conference in Nairobi.

The ferocious desert sun could provide the energy equivalent of 1.5 barrels of oil per square kilometre, said Gerhard Knies, project manager for Trans-Mediterranean Renewable Energy Cooperation (TREC), at a meeting of nine African states.

“The largest source of energy is the solar radiation (and) the best place to receive solar radiation is the desert,” he told reporters at the start of meeting of 20 parliamentarians in Kenya.

“Deserts get 700 times more energy per year than all human kind is using,” he explained.

“It is as if a layer of 25 centimetres of oil is falling down in the deserts year after year”

The legislators from Burundi, Djibouti, Ethiopia, Kenya, Madagascar, Rwanda Tanzania, Uganda and the Seychelles are at the conference to discuss energy access for the poor.

“There is great need to provide the poorest people in east Africa with electricity,” said Nicholas Dunlop, founder of the “e-parliament” conference. “But at the same time there is an urgent need to combat climate change.”

Dunlop explained that the technology needed to provide solar thermal energy was simple and clean compared to extracting and processing fossil fuels. “A combination of mirrors and pipes to concentrate the sun’s heat to boil water and drive an old fashion steam turbine. One you have built your mirrors and pipes ... your costs are finished. The good Lord does the rest,” he said.