ECE Newsletter Issue 3

Quarterly-Published Newsletter of

ISSUE

03 June 2009

THE DEPARTMENT OF ENGINEERING University of Nicosia

Department News During the past academic year, the Department of Engineering has gone through a thorough evaluation of the existing curricula for the Electronics & Computer Engineering programs. As a result, significant improvements and additions to existing courses were introduced, especially in the areas of engineering electives and major requirements. Τhe two engineering pathways were re-engineered in such a way as to better conform to international guidelines of professional accreditation bodies such as the Accreditation Body of Engineering and Technology (ABET) of the USA and the Engineering Council of the United Kingdom (ECUK). Special emphasis was placed in Power Engineering where a total of five new courses were added, thus introducing a new concentration in Power Systems and Automation. The new pathways for the Electronics & Computer Engineering programs will be implemented in the Fall of 2009.

The Department applied for the first time, back in June 2008, to the Cyprus Scientific and Technical Chamber (ETEK) for registration.

We were recently informed that ETEK had already assigned a committee to look into the application packages of all private universities in Cyprus. As of today, we have not received any official answer back from the Technical Chamber. In April 2009, right after the re-engineering process of the two engineering pathways, the Department Council unanimously decided to re-apply to the ETEK by submitting the new pathways.

Around the same period, we informed the Evaluation Committee for Private Universities (ECPU) on the new updated pathways and our recent application to the ETEK for institutional membership and registration. Our request to the ECPU was their permission to change the name of the Electronics Engineering program to Electrical Engineering as the latter better represents the substance of the program and the underlined areas of concentration.

Prof. Anastasis Polycarpou Head – Dept. of Engineering

Get Tuned

Engineering the Formula 1 K.E.R.S.

By Dr Stelios Neophytou

This issue Engineering the Formula 1 K.E.R.S. Hybrid Cars Eye on Technology Answer to Last Issue’s Tech Tip Did you know that …

For the fans of Motor Sports, Formula 1 is said to be top racing championship in the planet. For us engineers, Formula 1 (F1) is where sports meet cutting edge technology combining a number of different specializations and, thus, different kind of engineers. A few years ago, the international automotive federation (FIA) announced that F1 teams can no longer work on developing the engines of F1 cars in order to give motivation on developing environmentally friendly technologies. The first attempt has been launched in this year championship with the so called Kinetic Energy Recovery System, commonly known with the acronym KERS. But how does this system actually work?

Essentially, KERS utilizes the fact that an electric motor can also act as a generator. The vehicle's electric traction motor is operated as a generator during braking and its output is supplied to an electrical load. This transfer of energy to the load provides a braking effect, known as Regenerative Braking, which makes the car decelerate. Hence, the mechanical (kinetic) energy produced by this braking process is converted to electrical energy using the electric motor

that gives motion to the car as a generator. This setup has been known among engineers for more than half a century and is used in other applications; however KERS goes a step further by storing the produced energy and give it back to the traction system as extra accelerating power.

Two different approaches have been used so far by F1 teams for storing the energy. The first approach uses a KERS charged battery. The second and most interesting approach uses a flywheel, a device that stores energy as rotational energy. You can imagine this as a clockwork toy, but instead of using hand power, kinetic power from the braking is applied to a rotor inside magnetic bearings.

From what we know, only one F1 team uses the flywheel approach with the engineers hoping that the long life characteristics of a flywheel will help in having fewer failures during the stress of a demanding F1 race.

Continues on last page…

Did you know that … “static electricity” has nothing to do with charges at rest? Static electricity is synonymous to “high voltage” electricity and is all about electrons objects

leaping between two that

have

opposing

electrical charges. When we walk across a wool carpet on a dry day, our shoes pick up electrons from the carpet. As we lift our foot off the ground, the electrons move

Hybrid Cars

By Dr George Gregoriou As hybrid cars are relatively new in the market, there seems to be some confusion among buyers as to what they are. A hybrid car is basically a fuel efficient car with two motors, namely, an electric motor and a gasoline powered motor. A hybrid car is not an electric one and, therefore, there is no need to be plugged in. Instead, it is equipped with a special system to capture braking energy to store in an additional higher capacity battery which is located on board.

away from our shoes, spreading through our entire body giving us a negative charge.

Every time we

put our foot back on the carpet, since our shoe has no extra electrons, more electrons leap from the carpet, through the shoe, to our foot and eventually we become full of electrons. This way, our body typically charges up to a potential of about 25,000 volts.

This is

some serious voltage, considering a normal electrical wall outlet potential is around 240 volts, but since the current is very low there is no real danger. As we reach for a positively charged doorknob or any other grounded object, electrons flee to it, giving us a slight shock. Often, this causes the air to break down and an electric spark to leap between our finger and the object.

Since the tiniest

spark requires about 500 volts, this proves that we are actually at a very high voltage and, therefore, the air between our hand and the knob becomes extremely hot and instantly turns to plasma (ionized gas).

The plasma gives off a

bright flash. This works just like a lightning bolt. The pop sound that results (similar to thunder) is due to air that is rapidly expanding and collapsing.

The mere existence of two motors combines the strengths of both types. When the driver decelerates or brakes, the motion of the slowing wheels turns the generator and creates energy that is used to recharge the battery - this is called regenerative braking.

This way, by utilizing the otherwise wasted energy, hybrids get better gas mileage in the city than conventional cars do. The electric motor uses no energy at all during idle - it turns off - and uses less than gas motors at low speeds. That means that during rush hour stop-and-go driving, the electric motor works great and, as an added benefit, does not produce any exhaust thus reducing smog levels. In fact, hybrid cars cut emissions by 25% to 35% over the most fuel efficient gas powered models. The gas motor does better at high speeds and can deliver more power for a given motor weight.

When accelerating on the highway, the conventional motor kicks in and, in conjunction with the electric motor, provides that additional much needed boost of power.

position, car speed, and battery charge, and relay the readings to a computer that decides how to optimally divide the load between the gasoline engine and the electric motor. The motors and batteries in these cars do not require maintenance over the life of the vehicle.

The engine doesn't need any more maintenance than in any other car. Because hybrids have regenerative braking, brake pads may even last longer than those in normal cars. There is, however, an increased complexity due to the existence of two motors and the ancillary systems to manage them plus a heavy battery used to produce electricity during braking and a regeneration system. To offset perceived reliability problems emanating from this complexity, hybrid car makers are offering strong guarantees. With only a marginal savings on gasoline and a much higher initial cost, hybrid car manufacturers are relying on two main factors to sell: the “green” image and the “new” technology.

Any marketer will tell you that “new” and “green” are good for any sales.

Hybrid cars are considered by the experts as a transition technology. Hydrogen or methane fuel cell powered cars are probably the cars of the future.

This Issue’s Q&

Note: A "muscle hybrid" is a vehicle that uses hybrid technology to increase power and performance rather than significantly increasing fuel economy--leading to

A number of sensors placed throughout the car monitor conditions such as throttle

an expensive vehicle with very low cost-effectiveness.

References: [1] PhysOrg.com [2] www.hybridcenter.org [3] www.technologyreview.com

Answer to last issue’s Technology Tip

EYE ON TECHNOLOGY Get tuned with the first nanoradio!

By Dr Antonis Hadjantonis Answer to previous issue’s question on why optical communication is considered faster when, in fact, the optical signal propagation speed is about the same as that of coaxial transmission.

spread into one another rendering both indistinguishable at the receiver and causing increased bit error rate (BER, the probability of receiving a bit in error). This is depicted in Figure 3.

By Dr Marios Nestoros On December 29, 1959 Richard Feynman

gave

a

prophetic

speech at the Annual Meeting of the American Physical Society with the title ‘”There's Plenty of 1

The truth is that in digital communications, we distinguish between propagation speed and transmission rate. The former deals with how fast signals travel in a medium (usually as a fraction of speed of light, c, in free space), while the latter indicates how many pieces of information (binary digits, or bits) we can transmit per unit time. In communication, high data rates, rather than fast propagation speeds, dictate how fast transmissions really are.

Figure 2. Effect of pulse distortion Now, various factors affect the transmission rates. It so happens that signals, as they enter the medium at the transmitting end, look exactly like we intend them to.

However, due to various physical effects (like noise), they look very bad and out of shape at the receiving end. How bad they get depends on factors like line conditions and the distance traveled. Transmission rate and length are mainly affected by pulse distortion due to noise (Figure 1), attenuation (Figure 2) and pulse broadening, due to dispersion.

Figure 2. Effect of attenuation Pulse broadening, which is a function of the communication link length, directly affects digital transmission rates by causing InterSymbol Interference (ISI), a condition when consecutive pulses

Room at the Bottom” , introducing the concept of nanotechnology. His vision concerned a new branch of science, which would deal with the control and manipu-

Figure 3. Effect of pulse broadening, or dispersion (on the top, an increased bit rata causes ISI; on the bottom, reducing the bit rate alleviates the problem)

lation of matter down to atomic dimensions.

In the following

decades the field of micro and nano-science developed rapidly.

A convention of measuring the quality of digital communication links is to have transmissions limited to the length and rate that conform to a specified BER (a common standard is one in a billionth, or better).

In the fiber, optical pulses experience reduced attenuations and limited broadening over longer distances, which allows us to transmit more bits in a given time window compared with electronic bit transmission (in fact, orders of magnitude more). Fibers have been demonstrated to transmit digital optical signals of 80Gbps over distances of more than a hundred kilometers, when electronic transmissions are only limited to about 10Mbps over some kilometers distance.

As if the above were not enough, in optical communications we can further deploy frequency multiplexing (which, in optical communication terminology we customarily call Wavelength Division Multiplexing or WDM) in order to simultaneously transmit the above capacity tens of times, each on a separate optical carrier channel, or wavelength. The result is that on a single fiber, we can transmit tens of Tbps (trillions of bps)!

Now that is orders of magnitude faster than electronic transmission, isn’t it?

Very recently the scientific group of Alex Zettl at the University of California, Berkeley constructed the first true nano-radio which actually consists of a carbon nanotube, of 500 nm length and 10 nm in diameter, fixed on a carbon

electrode.

A

carbon

nanotube is simply a hexagonal arrangement of carbon atoms that can be rolled up to make a cylinder. Due to the exceptionally strong chemical bond between the carbon atoms, nanotubes can withstand a very high tensile strength. In addition they present extremely high electrical conductivity.

The amazing thing about the single nanotube is that it can perform all the functions of a radio. Namely it can receive a signal by mechanically vibrating at the specific frequency and it can tune at any radiofrequency by applying an electric tension to it in a similar way a guitarist can tune a metal cord by pressing it.

Continues on last page…

Engineering Continued

Engineering Joke An engineer dies and reports to the

pearly

gates.

St.

Peter

checks his dossier and says, "Ah, you're an engineer -- you're in the wrong place." So, the engi-

the

Formula

1

K.E.R.S.:

Moreover, since flywheel is storing mechanical energy (rotational), and kinetic energy is itself mechanical, energy does not change state and is therefore more efficient. The main disadvantage of this approach is the larger weight which can disturb the balance of the vehicle and increase the fuel consumption.

and is let in. Pretty soon, the engineer gets dissatisfied with the level of comfort in hell, and designing

improvements.

and building After

In addition, it can amplify a signal and demodulate it. The first song played on Zettl’s team nanoradio was “Layla” by Eric Clapton. You can visit the website in [3] to hear the original transmission of the song from the nanoradio.

The applications of this nano-device can be tremendous. Some applications in medicine could be nanoradio-controlled drug delivery systems which release their chemical “bombs” in the tumor cells as well as nano-injections where nanotube structures are introduced in cells and release specific drugs.

neer reports to the gates of hell

starts

Get tuned with the first nanoradio!

Continued

awhile,

they've got air conditioning and flush toilets and escalators, and the engineer is a pretty popular guy.

Another idea of Zettl and his group is to use the nanotube as a nano-chemical sensor since the vibration frequency of the nanotube is very sensitive to the mass of atoms/molecules attached on it.

These nanosensors could be an integral part of tiny robots moving in mines or airports, detecting minute amounts of carbon monoxide or explosives respectively. The same nanotubes would then transmit their information to the base station.

One day, God calls Satan up on the telephone and says with a sneer, "So, how's it going down there in hell?"

Satan replies,

"Hey, things are going great.

We've got air conditioning and flush toilets and escalators, and there's no telling what this engineer is going to come up with next."

God replies, "What???

You've got an engineer? That's a mistake -- he should never have gotten down there; send him up here."

Satan says, "No way. I

like having an engineer on the staff, and I'm keeping him." God says, "Send him back up here or I'll sue."

Satan laughs uproari-

ously and answers, "Yeah, right.

And just where are YOU going to get a lawyer?"

Department of Engineering UNIVERSITY OF NICOSIA 46 Makedonitissas Avenue P.O. Box 24005 1700 Nicosia CYPRUS (+357) 22841500 phone (+357) 22357481 fax www.unic.ac.cy

Despite the fact that KERS is not expected to give serious advantage in terms of the overall horsepower of an F1 car, this project aims in helping the development of environmentally friendly and road car-relevant technologies. It looks like vehicle manufactures have concluded that building a fully electric powered car is not the best solution to the environmental problem. Yet, taking advantage of the mechanical energy that would be wasted otherwise can decrease the overall fuel consumption and, consequently, the CO2 emissions for road cars.

Figure 4. Courtesy Zettl Research Group, Lawrence Berkeley National Laboratory and University of California at Berkeley."

References: [1] http://www.zyvex.com/nanotech/feynman.html [2] Ed Regis, “The world’s Smallest Radio”, Scientific American, March 2009.

[3] http://www.physics.berkeley.edu/research/zettl /projects/nanoradio/radio.html