Edmund Melson Clarke, Creator of Model Checking, Dies at 75

IEEE also mourns the loss of F.C. Kohli, India’s ‘Father of IT Industry,’ and others

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Joanna Goodrich is the associate editor of The Institute

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Edmund Melson Clarke

Model-checking creator

Fellow, 75; died on 22 December

Clarke was a computer-science pioneer who helped develop model checking, an automated method for finding design errors in computer hardware and software. Intel, Microsoft, and other companies use the method to verify designs for integrated circuits, computer networks, and software.

He died from COVID-19 complications.

Clarke initially studied mathematics and received a bachelor’s degree in the discipline in 1967 from the University of Virginia, in Charlottesville, and a master’s degree in 1968 from Duke University, in Durham, N.C. But when he was a doctoral student at Cornell, he changed his field of study to computer science. He conducted his thesis research under the guidance of Robert L. Constable, a pioneer in making connections between mathematical logic and computing.

After graduating in 1976, Clarke joined Duke as a computer science professor. In 1978 he began teaching computer science at Harvard. While there, Clarke and his doctoral student E. Allen Emerson conducted research on methods that could be used to effectively verify how a system performs without errors. In 1981 they published a paper on model checking, “Design and Synthesis of Synchronization Skeletons Using Branching Time Temporal Logic,” in Logics of Programs.

In 1995 Clarke led a team that tested the method on an IEEE standard for interconnecting computer components. They discovered flaws in the standard’s design—which spurred the tech industry to use model checking on its systems.

Clarke, along with Emerson and computer scientist Joseph Sifakis, received the 2007 Association for Computing Machinery A.M. Turing Award.

In 1982 Clarke joined Carnegie Mellon, where he worked as a professor of computer science and electrical engineering. He was named an emeritus professor in 2015.

He served on the editorial board of IEEE Transactions on Software Engineering.

If you’ve had a family member who was an IEEE member pass away due to complications from COVID-19 and would like an obituary published by The Institute, contact the editors: institute@ieee.org.

Joseph R. Asik

Research scientist

Life senior member, 82; died 17 July

From a young age, Asik was rarely known to leave home without pens, pencils, and a Swiss Army knife, ready to tackle life’s problems, according to his obituary.

He was awarded several scholarships after graduating high school and received a bachelor’s degree in physics in 1959 from the Case Institute of Technology, now Case Western Reserve University, in Cleveland. During his time as an undergraduate, he was an intern one summer at the U.S. Department of Energy’s Oak Ridge National Laboratory, in Tennessee, where he worked on a secret atomic project, according to the obituary.

Asik was a research scientist at Ford for 30 years. While there, he was granted 22 U.S. patents.

After he left Ford, he joined Lawrence Technological University, in Southfield, Mich., as a part-time lecturer on automotive and electrical engineering.

Asik had many interests and hobbies including amateur radio, gardening, and cooking Hungarian food.

He received both a master’s degree and a Ph.D. in physics from the University of Illinois at Urbana-Champaign.

Robert F. Heile

Co-founder of an IEEE Wi-Fi standards group

Life member, 75; died 24 September

Heile was serving as chairman of the IEEE 802.15 Working Group for Wireless Specialty Networks at the time of his death. The group, which he co-founded in 1990, is developing standards for the Internet of Things.

After receiving a Ph.D. in physics from Johns Hopkins University, in Baltimore, Heile joined chemical manufacturer Union Carbide in Houston. He left there in 1980 and became vice president of business operations and transmission products at Codex, in Canton, Mass., where he oversaw development of modems and wireless networking devices. In the 1990s he was a vice president at several Massachusetts companies including TyLink and Windata.

He joined BBN Technologies, in Cambridge, Mass., in 1997 with the mission of developing business strategies to commercialize the company’s wireless technologies, according to his obituary. After the company was acquired by GTE—now part of Verizon—Heile left to become a consultant.

His work at BBN led Heile to get interested in technology standards, according to his obituary.

Heile helped create the ZigBee Alliance, an IEEE Industry Standards and Technology Organization group responsible for developing and promoting the Internet of Things. He served as its chairman and CEO until 2013, when he joined the Wi-SUN Alliance as director of standards and chief representative for business development in greater China.He received a bachelor’s degree from Oberlin College, in Ohio, and completed his master’s degree and doctorate in physics at Johns Hopkins.

Noah Hershkowitz

Plasma physicist pioneer

Fellow, 79; died 13 November

Hershkowitz’s research broadened the understanding of the fundamental properties of plasma. His pioneering work on emissive probes, which are small electrodes that are heated until they emit electrons, resulted in the development of a technique for determining plasma potential. This charge of electric and magnetic fields surrounding the plasma can be analyzed by the current emitted by the emissive probe. In 2002 Hershkowitz became the first to measure plasma potential throughout the sheath and presheath—the regions surrounding the plasma with positive ions and neutral atoms—in a weakly collisional plasma made from weakly charged particles.

Hershkowitz began his career in nuclear physics. He changed his field of study because plasma physics “looked like it would be more fun,” according to his obituary.

He was a professor at several institutions including the University of Colorado Boulder, the University of Iowa, and the University of Wisconsin–Madison, before retiring in 2012.

Mentor to more than 50 doctoral students, he was named professor emeritus at the University of Wisconsin after retiring.

He received numerous awards during his career, including the 2004 James Clerk Maxwell Prize for Plasma Physics, the highest honor afforded by the American Physical Society’s Division of Plasma Physics, and the 2015 IEEE Marie Sklodowska-Curie Award for innovative research and inspiring education in basic and applied plasma science.He received a bachelor’s degree in physics in 1962 from Union College in Schenectady, N.Y., and in 1966 earned a Ph.D. in physics at Johns Hopkins, in Baltimore.

Thomas D. Walsh

Power systems engineer

Life senior member, 90; died 13 November

Walsh joined Boston Edison in 1950 as an apprentice lineman and retired in 1993 as manager of transmission and distribution. After retiring, he worked as a consultant in the United States and Asia.

Walsh also was a professor at Quincy College, in Massachusetts, and he served on Northeastern University’s RE-SEED program committee, which aims to improve science education in public schools.

He holds several U.S. and Canadian patents and authored numerous technical papers and journal articles.

Walsh had been a Boy Scouts of America leader since 1969 and was awarded the 1999 Silver Beaver Award, which recognizes distinguished service in the organization.

He received a bachelor’s degree from Northeastern, in Boston, and a master’s degree from Lesley University, in Cambridge, Mass.

Pinar Boyraz Baykas


Senior member, 39; died 14 November

Boyraz Baykas was an associate professor at the Chalmers University of Technology, in Gothenburg, Sweden, at the time of her death. She conducted research in the applications of mathematical modeling, mechatronics, signal processing, and control theory.

After receiving her Ph.D. in mechatronics in 2008 from Loughborough University, in England, Boyraz Baykas joined the University of Texas at Dallas as a postdoctoral research associate. Her research focused on driver behavior modeling and active safety-system development.

She joined Istanbul Technical University as an assistant professor in 2010 and conducted research in applied robotics. In 2014 she was awarded a research fellowship from the Alexander von Humboldt Foundation, which aims to promote international scientific collaboration. Through the fellowship, in 2016 Boyraz Baykas joined Leibniz University Hannover, in Germany, where she continued her research.

“Her effort to survive in a competitive academic world will hopefully pave the way for younger generations of women and help improve gender balance in academia,” Marco Dozza, her research colleague at Chalmers, told The Institute.

She received two bachelor’s degrees in 2004—one in mechanical engineering and the other in textile engineering—from Istanbul Technical University.

F.C. Kohli

Former Tata Consultancy CEO

IEEE member, 96; died 26 November

Kohli is referred to as the “Father of the Indian IT Industry” for his contributions to establishing and growing the field through his leadership of Tata Consultancy Services. He led a team that installed a computer system to control the power lines between Mumbai and Pune.

Kohli received a bachelor’s degree from the University of the Punjab, in Lahore, India. During his final year at the school, he joined the Indian Navy. While waiting for his assignment, however, he applied for and was awarded a scholarship to Queen’s University in Kingston, Ont., Canada. He graduated with a bachelor’s degree in electrical engineering in 1948 and joined Canadian General Electric in Toronto. While working there, he pursued a master’s degree in electrical engineering at MIT.

After graduating in 1950, Kohli began working in power system operations at Ebasco, the Connecticut Valley Electric Exchange, and the New England Electric System. After a year, he returned to India and joined the Tata Electric Co. in Mumbai, where he helped set up a load-dispatching system to help manage the company’s operations. He was promoted to general superintendent in 1963 and eventually became deputy general manager. When he was promoted to director, he introduced advanced engineering and management techniques for power systems operations.

In 1969, at the request of J.R.D. Tata, chairman of the company, Kohli helped set up Tata Consultancy Services, a subsidiary that provides IT services and business solutions. It is now one of the world’s largest IT software services providers, according to an article on business news website Mint.

Through the new service, Kohli led the installation of the computer system between Mumbai and Pune.

Tata was only the third utility company in the world to install such a system, according to Kohli’s obituary.

Kohli became the company’s first CEO and spent 30 years in the position until stepping down in 1996.

He was the 1995–1996 president and chairman of NASSCOM, an Indian IT services advocacy body in New Delhi, and then served on the organization’s executive committee. He helped shape global partnerships and showcase opportunities to deliver IT services from India, according to the obituary.

Norman Abramson

ALOHAnet developer

Life Fellow, 88; died 1 December

Abramson led the team at the University of Hawaii at Manoa, in Honolulu, that developed ALOHAnet, which allowed computers to transmit packets over a shared channel as soon as they had information to send. ALOHAnet was the first use of wireless communications for a data network.

Abramson began his career as a research engineer in 1953 at Hughes Aircraft in Westchester, Calif. Two years later, he joined the faculty at Stanford and taught at the university for 10 years. Some of his early research was in radar signal characteristics, sampling theory, frequency modulation, digital communication channels, pattern recognition, machine learning, and computing for seismic analysis.

He was a visiting professor at the University of California, Berkeley, in 1966 before joining the University of Hawaii in 1968 as a professor of electrical engineering and computer science.

When he joined the university, he was tasked with developing radio technology to help the school send data from its remote geographic location to the continental United States, and vice versa, according to his obituary.

ALOHAnet was deployed in 1971, and its protocol is now widely used in nearly all forms of wireless communications.

Abramson retired in 1994 and helped found Aloha Networks in San Francisco, a communications technology supplier.

He received a bachelor’s degree in physics from Harvard in 1953, a master’s degree in physics in 1955 from the University of California, Los Angeles, and a Ph.D. in electrical engineering in 1958 from Stanford.

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