Three electrical and computer engineering majors have been honored for their research in recent competitions, underscoring Lafayette’s outstanding student-faculty research program in the discipline and its national leadership in undergraduate research.
Prashant Poddar ’04 of Ranchi, India, who also is earning an A.B. degree with a major in economics and business, took first place last month in the research paper contest at the Institute of Electrical and Electronics Engineers (IEEE) Region II Student Activities Conference hosted by Cleveland State University. Region II includes Pennsylvania, Delaware, Ohio, West Virginia, Maryland, northern Virginia, and Washington, D.C.
In addition, as the lone undergraduate among 15 graduate students, Poddar took second place last month in the student paper contest at the IEEE Sarnoff Symposium on Advances in Wired and Wireless Communications in Princeton, N.J. His coauthored paper with research mentor William Jemison, associate professor of electrical and computer engineering at Lafayette, and others, “Optimization of Optical/Microwave Interaction in a Mode-Locked Microchip Laser,” was published in the symposium digest. Other students competing in the contest hailed from Princeton, University of Pennsylvania, Rochester Institute of Technology, Polytechnic University, Royal Melbourne Institute of Technology, Lehigh University, and other universities. Experts in the communications field judged the competition.
Poddar used microwave-photonic techniques to improve high-speed wireless applications such as telemedicine, multimedia distribution, and advanced satellite and military communications. He worked in collaboration with the Center for Microwave-Lightwave Engineering at Drexel University, which has modified its laser design as a result of his research. The project was related to Jemison’s ongoing work that is funded by a grant from the Office of Naval Research. (Further details on the three Lafayette students’ research are given in the second half of this press release.)
Poddar will pursue a Ph.D. in microwave communications at Purdue University, having gained admission to several of the top ten engineering programs in the country, including University of Michigan at Ann Arbor and Georgia Institute of Technology.
“This has been directly due to the opportunities and training that Lafayette has provided,” he says. “Some professors at these institutions expressed surprise at some of my undergraduate experiences.”
Last year, Poddar marked an unprecedented accomplishment for an institution, becoming the fourth Lafayette student in as many years to receive an IEEE Microwave Theory and Techniques Society Undergraduate/Pre-Graduate Scholarship. Poddar, who was featured last fall in the quarterly IEEE MicrowaveMagazine, presented results from his research with Jemison and Guangxi Wang ’03 (Shanghai, China) — one of just three students to win a Microwave Scholarship in 2002 — at the 16th Annual National Conference on Undergraduate Research (NCUR) as a sophomore. Jemison’s microwave project is funded by a $124,254 grant from the National Science Foundation.
Poddar collaborated with a group of Lafayette students on a research project guided by Rich and presented by electrical and computer engineering major Christopher David ’04 (Sandy Hook, Conn.) at NCUR last month.
He also presented his EXCEL Scholars economics research on game theory with Chris Ruebeck, assistant professor of economics and business, at NCUR last year. In Lafayette’s EXCEL Scholars program, students assist faculty with research while earning a stipend. EXCEL has helped to make Lafayette a national leader in undergraduate research. Many of the more than 160 students who participate each year share their findings in academic journals and/or conference presentations.
Poddar has served as president of Lafayette’s student IEEE chapter, was a two-time member of the Athletic Gold Roll of Honor as a member of the fencing team, and is a member of the Phi Beta Kappa, Tau Beta Pi (engineering), and Omicron Delta Epsilon (economics) academic honor societies. He also has been president of the campus Asian Cultural Association, a head resident adviser, and a writing associate, assisting fellow students with their writing skills. He served as chair of events planning for International Students Association’s annual extravaganza and has been active in volunteer and peer tutoring, Lafayette Leadership Education, Investment Club, and Wine Society. He is proficient in four computer programming languages.
Poddar received several Lafayette awards, including the William G. McLean Prize, awarded to a sophomore based on academic performance, campus citizenship, and professional orientation; the Mid-Atlantic Association of College and Housing Officers’ Academic Excellence Award; the J.J. Ebers Memorial Award for high academic achievement and professional interest in the field of electrical and computer engineering; and the Institute of Internal Auditors Award for excellence in accounting and business subjects.
Eric Geissenhainer ’04 (Emmaus, Pa.) is the second Lafayette student in two years to win the Walter B. Morton Student Paper Contest, which was held last month by the Lehigh Valley Section of the Institute of Electrical and Electronics Engineers. His paper reported on his successful development of energy-efficient analog power amplifiers for applications ranging from robots and wired data communication systems to consumer audio. Geissenhainer is scheduled to earn honors after completing and defending the yearlong, independent research project, which was guided by John Nestor and David Rich, associate professors of electrical and computer engineering.
He coauthored an article with the professors, Matthew Johnston ’03 (Nantucket, Mass.), and others that was presented at the AudioEngineering Society’s 115th Convention in New York City last October and published in the conference proceedings. He also presented his work at the 18th annual National Conference on Undergraduate Research last month and is among the small percentage of students whose papers will be published in the conference proceedings.
Previously, Geissenhainer worked as an EXCEL Scholar with Rich to find ways of speeding up Internet connections.
“Lafayette is an excellent place to conduct research,” he says. “The ECE professors do research in many different fields. This enables the students to find and work with professors who have similar interests.”
Geissenhainer will serve an internship this summer at Agere Systems in Allentown, Pa., before pursuing a Ph.D. in electrical and computer engineering at Oregon State University, which is providing a research assistantship.
“My thesis work and the research papers that I wrote have helped prepare me for graduate studies,” he says. “The research has been a learning experience and the papers have shown me how to better express engineering concepts for conference papers. I will be able to use my previous knowledge as a guide to help me with the more challenging graduate-level research.”
(Last year’s Walter B. Morton winner, Brandon Cochenour ’03of Lower Burrell, Pa., worked on improving the way that stereo loudspeakers deliver sound. He published his research in Journal of the Audio Engineering Society and was invited to present it at the 114th Audio Engineering Society Convention in Amsterdam, Netherlands.)
Pujitha Weerakoon ’04 (Kandy, Sri Lanka) won third place for his oral presentation among about 30 entries at the Northeast Bioengineering Conference hosted by Western New England College last month. Weerakoon presented a research breakthrough that would increase safety, enhance monitoring, and eliminate expensive, invasive surgery when ventricular assist devices are used as a “bridge” cardiovascular system for patients awaiting donor hearts for transplant.
“Lafayette is a great institution with faculty who genuinely care about your future and well being,” he says. “As an international student, I can say that [my research professors] have all helped me not only academically, but also in various other ways to survive in a competitive environment and yet to get my priorities right. Lafayette’s research program is an excellent opportunity to investigate diverse areas and I frankly believe that this is what separates Lafayette’s undergraduate program from any other school.”
At the conference, Weerakoon andMatthew Loh ’04 (Singapore) each presented independent research guided by Yih-Choung Yu, assistant professor of electrical and computer engineering, for which they are scheduled to earned honors in electrical and computer engineering. Their research with Yu was funded in part by a grant from the Lindback Foundation to improve testing procedures for heart assist devices and enhance cardiovascular physiology instruction.
Weerakoon and Loh also presented their findings last October at a session sponsored by the National Science Foundation’s Research Experience for Undergraduates program at the annual meeting of the Biomedical Engineering Society in Nashville, Tenn.
Last year, Weerakoon shared the results of an EXCEL Scholars research project he conducted with Ismail Jouny, associate professor and head of electrical and computer engineering, on retrieval of email through voice at the Institute of Electrical and Electronics Engineers’ International Conference on Multimedia and Expo in Baltimore, Md. His research was published in the proceedings of the annual conference, which brings together hundreds of researchers, engineers, and students to discuss state-of-the-art research, technologies, and applications in multimedia.
This school year, he worked as an EXCEL Scholar with Rich to investigate FM receiver systems that would reject signals from channels adjacent to the one selected by the user. He also has conducted EXCEL work with Rob Root, associate professor of mathematics, to develop a model for fish propulsion
Weerakoon received offers of full scholarships from Yale, Carnegie Mellon, Drexel, and University of Pittsburgh to pursue a Ph.D. in bioengineering, and has chosen Yale.
“I think Lafayette has prepared me well and I am looking forward to challenging myself,” says Weerakoon, a member of the Eta Kappa Nu and Pi Mu Epsilon national honor societies for electrical & electronic engineering and mathematics, respectively. He also belongs to Lafayette’s International Students Association and has served as a resident adviser. He toured Europe and Asia as a member of a professional dance troupe.
Laser for high-speed wireless signals
Poddar’s work involved development of a microchip laser. He investigated and improved the microwave coupling in a specific type of laser to enhance its performance. The laser can be used for transmission of high-speed wireless signals over optical fiber in hybrid fiber optic microwave communication links, which are called fiber radio, he explains.
“It required the usage of electromagnetic and basic laser theory, together with intensive simulations using industry standard state-of-the-art software, Ansoft HFSS,” he says. “Investigating and solving a problem that hasn’t been solved before can be thrilling!”
Poddar credits Jemison with being demanding, yet understanding.
“Combined with his expertise and resourcefulness, he has been an outstanding mentor,” he says.
“It is certainly a great strength of Lafayette to be able to provide such complementary research opportunities to undergraduates,” says Poddar of his work in both engineering and economics & business. “The experience is invaluable in choosing a career path.”
Energy-efficient amplifier
One of the unique challenges of Geissenhainer’s research, says Rich, was that it involved diverse areas of electrical engineering: digital hardware design, signal processing, analog electronics, and integrated circuit design.
“Engineers are typically more comfortable specializing in one or two niches of the field, and it is rare to find a student with the facility to carry out work in a multi-dimensional design of this type,” he notes. “For his honors thesis, Erik created a novel merger of traditional operational amplifier concepts with several state-of-the-art techniques, including delta-sigma data conversion and field programmable gate array implementations of digital signal processors. He has validated the analytical description of his invention by completing a fully functional prototype. Based on the quality of Erik’s work, the first-place honors at the Morton competition are well deserved.”
The amplifier designed by Geissenhainer and Rich last year was fabricated onto an integrated circuit chip, which was used for a new hybrid called a “PWM Class AB amplifier.” The unit is designed to be more energy efficient than standard Class AB amplifiers through use of power supply rails that vary at the same rate as the amplified signal. This minimizes the amount of power dissipated inside the amplifier.
“The project was very interesting due to the various applications that can utilize this design,” says Geissenhainer. “These applications range from audio amplifiers to motor controllers. Higher power efficiency in portable audio devices will result in longer battery life.”
Working with Geissenhainer has been one of Rich’s most satisfying experiences at Lafayette, the professor says.
“Erik is an exceptionally mature, motivated, and well spoken individual who, when asked to accomplish x, often returns 2x,” he says. “Erik thinks like an engineer and his lab skills are equivalent to a senior technical associate at any of the best shops; this skill-set is quite unusual to find at the undergraduate level. As Erik gains more exposure to advanced theoretical concepts, watch out — he is poised to do great things. The professor whose research group Erik joins in graduate school will be very lucky indeed as they will have a prolific collaborator on their hands.”
Rich and Nestor provided guidance and insight that kept the research on track, says Geissenhainer. “Dr. Rich is very knowledgeable and has had much experience working with amplifiers,” he adds. “His amplifier background helped us construct our new amplifier model.”
Helping heart transplant patients
According to the American Heart Association, an estimated 17 million people worldwide die of cardiovascular diseases every year. The demand for heart transplants for those with severe heart failure far exceeds the supply, says Weerakoon. For many patients, a ventricular assist device (VAD) offers a satisfactory alternative as a “bridge” to transplants. However, evaluating cardiac function usually requires invasive surgery to install pressure and flow sensors, which can only be performed at certain clinical facilities.
“If an indirect index of [cardiovascular function] can be identified from the measurements of a ventricular assist device without any indwelling sensor, this would facilitate an effective way to monitor the healthy condition of the patient’s heart while the patient is under VAD support,” says Weerakoon. “This would increase the patient’s safety and reduce the cost of surgery to do invasive testing.”
A major issue addressed by the research is the recovery of patients’ hearts after removal from VAD support. Currently, doctors can’t predict if a specific patient’s heart could recover by itself, says Yu. The time to wean the patient from VAD support is also critical. Removing VAD too early or too late would increase the possibility of the patient’s death in the near future.
Weerakoon’s work proved that a patient’s heart function can be detected in real-time using the electrical signals from the VAD as it continuously interacts with the heart, eliminating the need for an additional sensor. By integrating his algorithm into the VAD control console, says Yu, the cost for medical care can be minimized.
“This feature could be used to control the VAD to gradually wean the patient from mechanical circulatory support,” adds Weerakoon.
His research is unique because while others have presented techniques that can be performed without interrupting VAD operation, they use indwelling sensors and do not offer real-time detection of subtle changes in cardiovascular function.
“I am very excited about his results and will prove this concept in animal trials in the future,” says Yu, noting that the student is “hard working” and has wide interests in research.
Weerakoon considers Yu one of the best teachers he has ever encountered.
“He is a tremendous mentor,” he says. “He is well organized and has an outstanding knowledge about the work I am doing. He helped me to get started and then gave me pretty much a free hand to do my research. He was always there to help me when I needed him. He also helped me to polish up my presentation skills by presenting our work to several national conferences. His influence has not been limited to my research, but has helped me to redefine my career goals as well.”
As a national leader in undergraduate research, Lafayette sends one of the largest contingents to the National Conference on Undergraduate Research each year. Forty-two students were accepted to present their work at the annual conference last month.
Lafayette ranks No. 1 among all U.S. colleges that grant only bachelor’s degrees in the number of graduates who went on to earn doctorates in engineering between 1920-1995, according to the Franklin and Marshall College study “Baccalaureate Origins of Doctoral Recipients.”