In Memoriam: Professor Avram Bar-Cohen (1946–2020)
Who Was Instrumental in Laying the Scientific Foundation for the Thermal Management of Electronics

Contributed by the Heat Transfer Division of ASME for publication in the
JOURNAL OF HEAT TRANSFER. Manuscript received November 18, 2020; final
manuscript received December 15, 2020; published online February 2, 2021. Assoc.
Editor: Portonovo S. Ayyaswamy.

Journal of Heat Transfer

Avi briefly left his studies at the Massachusetts of Technology(MIT), where he was, at 5’7”, their All-New England Goalie, toplay soccer at the semiprolevel for the Boston Tigers in the American Soccer League in the late 1960s. Ultimately, rather than try
out for a professional soccer team, a viable option, he decided toreturn to MIT. He described himself in a 2013 interview with Professor Harry Dankowicz, Editor-in-Chief of Applied Mechanics
Reviews, as a “very springy goalkeeper” [2]. Anat and Avi’s firstson, Barak, recently the chief operating officer of Bai Brands, wasborn in 1970. Barak currently directs a number of philanthropic
and technical projects in the U.S. and Israel and is based in Princeton, NJ, with his wife and three children. Avi completed his Ph.D.
degree at MIT in 1971, also under the supervision of Art Bergles,
and his Ph.D. thesis was entitled Boiling and Condensation in a
Liquid-Filled Enclosure [3]. His first of many publications in thisjournal was on his Ph.D. research and appeared in 1972 [4]. Even
while beginning his professional career at Raytheon and devoting
endless hours to soccer, he completed his 3 degrees at MIT in justover 7 years. Avi often quipped that “sleep is overrated.”
Ben Gurion University (BGU). In 1972, after employment as a
Senior Engineer and Section Manager of Advanced Thermophysics, again in the Missile Systems Division of Raytheon Company,
Avi returned to Israel. He started his professional academic career
at Ben Gurion University (BGU), itself founded in 1969 as the
University of the Negev, where he held a succession of appointments from lecturer to Professor until returning to the U.S. fulltime in 1988. Avi’s belief that human ingenuity was capable, as
proved true, of developing the requisite technology to transformthe Negev from a relatively barren desert to its modern state andhis passion for Israel led him to BGU to be a founder of its engineering program. A photograph of him at BGU in 1974 is shownin Fig. 1 (left). Avi and Anat’s second son, Raanan, co-founder ofResolute Ventures, was born in 1975. Raanan, an early dot com
innovator, lives in the Bay Area with his wife and two daughters.
Early on at BGU, Avi’s research interests in engineering applications of thermal science were diverse, but he had a special interestin problems whose solutions could benefit the industrial economy
of both the still young State of Israel and that of the USA. In parallel, Avi was already examining the promising future of computerization and realized that its miniaturization required efficient
thermal solutions. He began research on this subject and helped toorganize the first conferences in the then emerging field of electronics cooling. He was also deeply involved in research concerning heat transfer mechanisms in developing two-phase flow boiling and condensation in tubes (see, e.g., Ref. [5]) and thehydrodynamics of fluidized beds (see, e.g., Ref. [6]). Such activities had direct implications on the U.S. and Israeli power industries. For example, the resolution of the circumferential anisothermality of inclined, diabatic pipes as a function of two-phase flow
regimes within them was of practical importance as it had
impeded design of reliable industrial steam generators. This
research required close cooperation with the steam generating
industries in the U.S. and Israel and a collaboration with suchwell-known colleagues as Professors Peter Griffith at MIT and
Yehuda Taitel at Tel-Aviv University. It was funded by the BiNational U.S./Israel Science Foundation (BSF).
Anat and Avi’s daughter Talia Litle, a professional modern
dancer, was born in 1981 and currently lives in the Bay Area withher husband and Avi and Anat’s sixth and seventh grandchildren.
Later in his BGU years, Avi published his seminal work on natural convection heat transfer between vertical plates with the lateWarren M. Rohsenow in this journal [7]. Every undergraduate
Mechanical Engineering student studies their results during thenatural convection portion of their Heat Transfer course. Even
more significantly, during this period Avi coauthored with AlanC 2021 by ASME
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Professor Avram Bar-Cohen, affectionally known to everyone
as Avi, passed away on Oct. 10, 2020. Throughout his life, distressingly cut short while he remained at his peak in every respect,
Avi was foremost and supremely devoted to his family, exhibited
contagious and indefatigable passion while making academicallyseminal and industrially paramount contributions to the fields ofheat transfer and electronics packaging, and zealously pursued hisother diverse interests ranging from economic theory to snowmobiling. We, a small contingent of the innumerable colleagues
and, without exception, friends, within Avi’s vast technical network are honored and humbled to pen this heartfelt tribute to him.
Anyone who has attended a lecture by Avi is familiar with his
mantra of “leave the world a better place,” Tikkun Olam in
Hebrew. He was, in so very many ways, profoundly successful inthis endeavor. A sampling of them are described here.
Early Years. Avi was born Avram Markowitz on Jan. 19, 1946
in Brooklyn, New York, the son of Simon and Dorothy Markowitz. Avi cherished the fact that 1946 was the same year that theworld’s first programmable electronic computer, the ENIAC, wasintroduced. Simon was a master plumber and later a technicalhigh school teacher, with whom Avi proudly apprenticed andthereby gained his first exposure to real-world heat transfer operations in the context of, e.g., steam pipes [1]. He was inspired byboth of his parents to become a gifted and dedicated educator. Avi
has an older sister, Tovah Reis, who lives in Bethesda, MD, andwas a senior medical librarian in hospitals and medical schools in
the U.S. and Israel. He also has a younger sister, Chani Fedrick,
who is a cantor in South Carolina. Their family roots on Simon’s
side trace back eight generations to what is modern-day Israel.
Avi spent his formative years between 1949 and 1957 in Holon,
then a small town in Israel and now part of the greater Tel Aviv
metropolitan area. He then returned to Brooklyn with his family.
While attending Abraham Lincoln High School, Avi successfully tried out for and excelled on the championship-winning
Danish Junior Soccer Team, part of the Empire State League [2].
Fittingly, while playing on the soccer field in 1962 at Camp Habonim in Red Hook, NY, Avi met his soulmate and future wife,
Anat, until recently the Executive Director of the Center for
Advocacy Training for the National Breast Cancer Coalition.
Their 58-year relationship was recently and aptly described bytheir daughter, Talia, as “the gold standard of love between two
individuals.”
On the academic side, Avi matriculated in the Department of
Mechanical Engineering at the Massachusetts Institute of Technology (MIT) in 1963. He completed his joint (honors program)
BS and MS degrees in 1968, as a Union Carbide Scholar and, subsequently, Cummins Diesel Fellow, with a minor in Managementof Technology, a lifelong interest, under the supervision of thelate Professor Arthur (Art) E. Bergles, a dear and enduring friend,
mentor and colleague. His MS thesis was on heat transfer in spray
towers. Notably, by 1968, Avi had also begun his professional
career as an Associate Engineer in the Missile Systems Divisionof Raytheon Company. Other invaluable mentors and then colleagues of Avi during and subsequent to his years at MIT, where
he returned for a sabbatical as a Visiting Associate Professor of
Mechanical Engineering in 1977–1978 during which he taught acourse on the Physics of Star Trek during the Independent
Activities Period (IAP), included the late Professors Warren M.
Rohsenow and August Ludwig Heselscherwerdt III, and Emeritus
Professors Peter Griffith and Borivoje Mikic.

Kraus (pictured with Avi in India in Fig. 1, middle), their seminal
book Thermal Analysis and Control of Electronics Equipment,
published in 1983 [8], a 620 page tome. Nearly 40 years later, itremains a standard reference in the field of thermal managementof electronics and, far ahead of its time, contains exhaustive chapters on technologies that only later became commonplace, such asheat pipes and thermoelectric modules.
Avi’s deep connections to Israel and BGU (and MIT and Raytheon) were conscientiously maintained for the rest of his life. For
example, just a few years ago he was again a co-investigator on a
BSF grant, this time as the U.S. partner of the late Professor Gad
Hetsroni of the Technion—Israel Institute of Technology. Again,
the topic, two-phase cooling for concentrating photovoltaic solar
cell arrays, themselves eminently relevant to the modern infrastructure and economy of the Negev, was aligned with current industrial
needs. Moreover, Avi was very active in recent IEEE International
Conferences on Microwave, Communication, Antennas andElectronic Systems (COMCAS), enormous biannual events held in
Tel-Aviv, where he was a plenary speaker. He also conceived andbrought to fruition a very successful Packaging and Thermal Management track for this conference. A photograph of Avi bestowing
an award on Professor Gennady Ziskind, current Head of Mechanical Engineering at BGU, at this conference is shown in Fig. 1 (right).
The organizers of the next COMCAS in November 2021 havealready announced their plans to dedicate a memorial session to Avi,a recurring theme at conferences throughout the world. It is also
because of Avi that Israeli researchers in heat transfer were allowed
to apply for Defense Advanced Research Project Agency (DARPA)
funding and complete a number of successful projects. Furthermore,
he initiated the formation of the IEEE Electronics Packaging Society
Chapter in Israel, formally approved on Oct. 4, 2020, days before his
untimely death. Finally, the Project Desert Nova Fund at BenGurion University was created by his children in honor of his countless contributions to technology and the Negev, on the occasion of
Avi’s seventieth birthday. The goals of the Fund were inspired by
Avi’s lifelong belief in the power of innovation in solving crucial
societal problems.
Years in Minnesota. Avi served as General Manager and Executive Consultant for packaging and physical modeling at Control
Data Corporation (Minneapolis, MN) from 1984–1989. Early during this period, in 1986, Avi was recruited by and joined suchluminaries in the field of heat transfer as Ernst Eckert, Ephraim
Sparrow, Richard Goldstein and Suhas Patankar, in the Mechanical Engineering Department at the University of Minnesota and030101-2 / Vol. 143, MARCH 2021

remained on their faculty until 2001. He taught courses on thermal
design, electronics cooling and boiling heat transfer andmultiphase flow. From 1988 to 1992, he jointly conducted withProfessor Terry Simon and graduate students research on boilingincipience, nucleate boiling, critical heat flux, boiling mechanisms, bubble dynamics, wetting, dissolved gas effects, and fluid
selection for electronics cooling. This led to joint publication of
22 conference and journal papers.
Subsequently, in his own Thermal Management of Micro- andNano-Systems (TherMNs) Laboratory, Avi was the principal
investigator for a broad portfolio of fundamental and appliedresearch sponsored by, e.g., 3M, Motorola, Intel, and NSF.
Research projects and industry collaborations covered topics suchas direct liquid immersion cooling, synthetic jets, gas-assisted
evaporative cooling, heat pipes, single- and two-phase heat sinks,
integrated circuit thermal characterization and modeling, thermoelectric refrigeration, and packaging adhesive and die-attachfatigue. Representatively, Avi’s research with Madhu Iyengar on
minimizing the total energy consumed by the fabrication and, inthe case of forced convection, fan driving air flow through a heatsink over its lifetime of operation [9] is featured in the standard
undergraduate textbook on Heat Transfer by Bergman et al. [10].
This work exemplifies Avi’s commitment to Tikkun Olam given
that, at present, about 1% of the world’s energy is used for thermal
management of electronics and this number is rising. Avi mentored and graduated 27 Master’s students and 10 Ph.D. students at
the University of Minnesota.
During his time at the University of Minnesota, Avi published
Design and Analysis of Heat Sinks [11], again with Professor Alan
Kraus. This is the definitive work on the subject. In addition, heedited over a dozen books and authored over 30 book chapters.
Overall, during his Minnesota years, Avi published over 60 peerreviewed journal articles, over 100 conference papers, and gaveover 60 invited and keynote lectures. He also pioneered the“classroom of the future” through live/synchronous, internetdelivered Thermal Management courses in collaboration with Professor Sushil Bhavnani at Auburn University and Professor
Yogendra Joshi at the University of Maryland.
Avi’s guidance to the student researchers was both in presenting his theories on fundamentals and in his discussions of the utility of the research results on the design of cooling solutions forelectronic devices. Between 1990 and 2005, Avi participated in
the Annual Review of the Heat Transfer Literature with the University of Minnesota Heat Transfer Division faculty. The reviews
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Fig. 1 Left: Avi at BGU, 1974. Middle: Avi and Professor Alan Kraus in India. Right: Avi bestowing an award on
Professor Gennady Ziskind, current Head of the Mechanical Engineering Department at BGU, at the IEEE International Conference on Microwave, Communication, Antennas & Electronic Systems (COMCAS) in Tel Aviv,
Israel, 2019.

were printed in the International Journal of Heat and Mass
Transfer.
Avi also contributed greatly to the administration of the Department and the College of Science and Engineering at the University of Minnesota as the Director of the Mechanical Engineering
Department’s Heat Transfer Division (1998–2001) and Directorof the College’s Center for the Development of Technological
Leadership (1998–2001). He held the Sweat Chair of Technological Leadership. In 2020, at an event to acknowledge the lifetime
contributions of Professor Ephraim Sparrow, the heat transfer faculty of the University of Minnesota chose two highly respected
members of the international heat transfer community to speak.
Avram was one. Photographs of Avi’s Group in the early and later
Minnesota years are shown in Fig. 2 (top left and bottom, respectively). A recent photograph of Avi and Professor Goldstein isalso shown in Fig. 2 (top right).
University of Maryland. Avi returned to the East Coast to chair
the Department of Mechanical Engineering at the University of
Maryland (UMD) from 2001 to 2010. He brought unprecedented
enthusiasm and energy to this Department, where he made substantial contributions to enhance both undergraduate and graduate
studies. Under his leadership, the Department’s national rankings
vastly improved, and its research expenditures increased by 63%.
Avi was also instrumental in transferring the Reliability Engineering Program to the Mechanical Engineering Department, which
helped strengthen their research activities in electronic reliability
in the Center for Advanced Life Cycle Engineering (CALCE),
one of the five centers currently in the Department, said Professor
Balachandran, Minta Martin Professor and Chair of MechanicalEngineering. In the words of Margaret (Peggy) Brumfield, theExecutive Director of Administrative Affairs during Avi’s tenure
as Chair, “Avi was the exemplary leader who knew how to
Journal of Heat Transfer

motivate the staff and most importantly knew what kind of fiscal
analysis he needed. He loved numbers and appreciated theirimportance as support to making good decisions on utilizing
departmental resources.” Avi was named a Distinguished University Professor at Maryland in 2005, the highest honor bestowed ona tenured faculty member. Photographs of Avi in his office at
Maryland and with his faculty colleagues are shown in Fig. 3, left
and middle, respectively.
At the international level, under Avi’s leadership, in 2002 theDepartment participated in a sponsored international research andeducational collaboration with the United Arab Emirates (UAE).
Through this multiyear collaboration, the University of MarylandCollege of Engineering participated in establishing an engineering
institution in the UAE. The institution (known as the Petroleum
Institute then and now part of Khalifa University) had six engineering programs, including mechanical engineering, whichboasted the highest student enrollment of them. The programs
included both undergraduate and graduate programs. In 2012, theinstitute was granted a six-year ABET accreditation for all of its
engineering programs and became the only institution in the UAEat the time to have all of its programs receive such high recognition. Under Avi’s leadership, Mechanical Engineering at UMD
played a major role in helping the institute achieve its envisioned
goals in instruction, research, and scholarly collaborations.
Michael Ohadi, a professor from the Mechanical Engineering
Department at UMD, on a professional leave assignment from
UMD, served as the founding Chairperson of the MechanicalEngineering Department (2002 to 2006) and later served as the
Provost and Acting President of the Institute (2006–2010). A
photograph of Avi and Dr. Daniel Mote, former President of the
University of Maryland (UMD), College Park, at one of their
meetings with a UAE colleague is shown in Fig. 3, right.
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Fig. 2 Minnesota years. Top left: “ABC Group” at Avi and Anat’s house—Mr. and Mrs. Devin Mix and Avi (toprow), Evan Graham, Andrew McNeil and Marc Hodes (middle row) and Khadir Mellah and Zane Johnson (bottomrow). Top right: Avi with Professor Richard Goldstein at Dick’s retirement celebration. Bottom: An “ABC lunch”
at a conference—Maurice Holahan, Avi, Karl Geisler, Madhu Iyengar, Gary Solbrekken, and Zane Johnson fromleft to right.

Fig. 3 Left: Avi during his tenure as Department Head at UMD. Middle: Professors Bill Fourney, Avi Bar-Cohen,
Art Bergles, and Michael Ohadi at UMD. Right: Avi and Dr. Daniel Mote, former President of UMD, with a colleague from the UAE.

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Raytheon. In 2016, Avi returned, after a 48-year hiatus, to Raytheon Corporation, this time as Principal Engineering Fellow in
the Space and Airborne Systems Division in Arlington, VA.
There, his interests, in addition to the thermal management ofelectronics, focused heavily on wireless power beaming technology. Avi, as mentioned above, started working for Raytheon as amechanical engineer in 1968 after completing a combined Bachelor’s and Master’s degree in Mechanical Engineering from MIT.
He was exposed to the challenges and opportunities associatedwith electronics cooling and Raytheon supported his Ph.D. studies, which turned out to be an excellent investment. Avi’s second
stint at Raytheon provided an opportunity to continue his efforts
in developing defense technologies to support U.S. DoD interests.
During this period, he served as a mentor and technical strategist,
helping shape Raytheon’s next generation of thermal engineers,
driving company strategy in thermal management, and increasing
the level of engagement between Raytheon engineering and thebroader thermal technical community. Avi’s work focused onthermal management of high-power density RF devices, highenergy lasers, hypersonics, modeling and simulation, 3D heterogeneous integration, and power beaming technologies. His longstanding relationships within the government and broader thermal
technical community gave rise to new collaboration opportunities
in thermal storage technologies, phase change heat transfer, hightemperature materials and cooling techniques, and optical powertransmission. While at Raytheon, Avi engaged at all levels, frominforming senior management to mentoring individual engineers.
He increased Raytheon’s technical profile by spearheading thegeneration of books and journal articles that laid out the past,present and future directions of thermal management to influence
the industry and inform future research directions. At the time ofhis passing, Avi was in the midst of fostering international collaboration between U.S. DoD and Israeli Ministry of Defense(IMoD) researchers to advance common goals. Innovation andcommitment to helping maximize the potential of every engineer
he worked with were the hallmarks of Avi’s tenure at Raytheon.
Publications. To describe all of Avi’s activities on the publications front, especially the tremendous number of highly cited journal papers, along with his own journal and book editing activities,
is unrealistic. Here, we mention a few of the book series he wasrecently editing. They include the well-known, high-impact Encyclopedia of Thermal Packaging (ETP, in 4 thematic sets, with 17
volumes in total) [13–16], essentially our community’s longawaited update to and vast expansion of the aforementioned Kraus
and Bar-Cohen [8] tome published in 1983. It is unparalleled in
the comprehensiveness of its scope. Topics included by Avi in the
ETP span the entire spectrum of thermal packaging aspects—fromfundamentals to techniques to tools to applications to configurations. One of the volumes is Avi’s 3rd book coauthored with Dr.
Karl Geisler and entitled Dielectric Liquid Cooling of Immersed
Components [17].
Avi also began a parallel project—a multiset, multivolume
Encyclopedia of Packaging Materials, Processes and Mechanics,
whose first set Interconnect and Wafer Bonding Technologies (in4 volumes) was just published [18]. In addition to theseTransactions of the ASME

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In addition to his research addressing the many practicalchallenges faced by the electronics industry, Avi was a strong
advocate for basic research and realized the importance of a partnership between government and the private sector to support thefoundational research needed to address future challenges and, ofequal importance, train the next generation of engineers. Shortly
after his arrival at the University of Maryland, he began a dialogue with the Office of Naval Research (ONR) regarding coolingchallenges the military would face as they moved toward higher
power electronic systems. Working with Professors Yogi Joshi
and Marty Cerza, Avi organized a workshop in 2003 to identify
future thermal challenges and the need for innovative research. As
a result of this workshop, ONR started a new program focused on
basic research in heat transfer. Many of the concepts developed
under that program found their way to Avi’s subsequent programs
at DARPA.
Avi’s administrative duties did not stop him from his active
research, collaborative, and scholarly activities. In fact, during his
years as Chair, 2001 to 2010, his impressive research and outreachactivities included 58 journal articles, 66 peer-reviewed conference papers, 44 invited plenary/keynote/other major lectures, andcountless other activities. The Mechanical Engineering faculty,
staff, and students will miss Avi’s distinguished intellect, engaging presence, momentum-building character, and his affablesmile.
DARPA. Avi went on assignment from UMD to the Microsystems Technology Office (MTO) at the Defense Advanced
Research Projects Agency (DARPA) in the fall of 2010, serving 2
terms through the end of 2015. During his time at DARPA, Aviinitiated and led the Intrachip Enhanced Cooling (ICECool) program, whose aim was to enhance the performance of electronicsystems through the application of chip-scale heat removal of
kW-level heat flux and heat density while simultaneously mitigating local electronic device hot spots. This program engaged boththe fundamental research community on microfluidic two-phasecooling in the ICECool Fundamentals thrust and the industrial
research community on near-term embedded cooling that would
have specific benefits to electronic performance in the ICECool
Applications thrust. In addition to ICECool, Avi initiated ICECool’s predecessor, the Near Junction Thermal Transport (NJTT)
program. He also served as the program manager for several otherprograms including Thermal Management Technologies (TMT),
Semiconductor Technology Advanced Research Network (STARNet), and a portfolio of advanced studies in laser diodes, as wellas dozens of seedling efforts including topics such as phononengineering, thermal-electrical-mechanical codesign, liquid metalcooling of electronics and heterogeneous integration. In his 2020
review article in the Journal of Electronic Packaging on theadvanced power amplifier work funded under ICECool [12], Avisummed up the results of the program in his own words: “theimplementation of the embedded cooling thermal paradigm
addresses the inherent thermal limitations of wide bandgap materials and enables far greater electrical and RF performance for the
coming generation of GaN devices and other compound semiconductor systems than available today.”Journal of Heat Transferof the IEEE CPMT Transactions (1995–2005), a tenure during
which he successfully recruited a number of excellent associate
editors. Even after stepping down from this position he continued
to take an active interest in the journal and helped shape its strategy. He served on the EPS Board of Governors and was Presidentof the IEEE Electronics Packaging Society. During his tenure, the
EPS society continued to grow internationally, developed a strategic Heterogeneous Integration Roadmap, successfully recruited
young professionals and developed a more broadly recognizableprofile, helped in no small part by Avi’s active and encouraging
stewardship. It is to Avi’s tremendous credit that he was able toseamlessly adopt multiple roles, of a highly regarded researcher,an engaged academic, an unassuming mentor, an always available
coach and a strategic visionary who could deftly translate vision
to action and through engaged encouragement involve and drawout the best from people. He straddled the ASME and IEEE communities (and their respective research in electronics and packaging) creating strong complementary efforts in both societies.
His work was recognized by the community thru multiple awards
of increasing levels of importance. He received the InterPACK
Achievement Award in 2005. He also received the Luikov Medalfrom the International Center for Heat and Mass Transfer in Turkey(2008) and ASME’s Heat Transfer Memorial Award (1999), theEdwin F. Church Medal (1994), and the Worcester Reed Warner
Medal (1990). He became a member of the European Union
Academy of Sciences in 2020. Prior to this, he had been made aLife Fellow of IEEE and ASME. He was awarded the CPMT Society’s Outstanding Sustained Technical Contributions Award (2002),
the ITherm Achievement Award (1998), and the THERMI Award(1997). The IEEE EPS community honored him with its highest
award, the prestigious CPMT Field Award in 2014.
Summary. A recurring theme that emerged during the assembling of this review of Avi’s contributions was that every coauthor
and innumerable others were helped on a personal level by Avi.
We provide but three examples. First, it was interactions with Avithat ultimately resulted in Professor Portonovo Ayyaswamy conducting workshops on cooling through the sponsorship of theUnited Nations Industrial Development Organization (UNIDCO)
with headquarters in Geneva. Second, it was Avi who enabled
Professor Ivan Catton to navigate the intricacies in applying inorganic aqueous solutions (IAS) to phase change heat transfer under
DARPA sponsorship. Thirdly, Professor Timothy Fisher recalls
meeting Avi at the very first technical conference that he attended,
ITherm ’96, and remembers in particular Avi taking the time tohave a long and deep technical conversation with him and otherstudents who were just entering the field. There was always a longline of folks wishing to speak with Avi at conferences (even to
take photos next to him in the case of younger students) and,always, he made time to reach the end of the line.
As has been made clear, the imprint Avi made on the people
with whom he worked and places where he worked will continue
in perpetuity. Once Avi engaged with an organization, be it Raytheon, BGU, or a professional society, it became a lifelong contract. The breadth of Avi’s vision, the extent of his grasp ofcurrent—and expected future—engineering needs and practicalapplications was matched by his practical, pragmatic approach.
There was no “pipe dreaming” in his truly prophetic vision—hisview of the actual needs of the engineering community and of thereal capability to deliver, coupled with his excellent understandingof economic viability of innovation, were all based in the realityof engineering research that he knew so well.
May Professor Avram Bar-Cohen, our esteemed colleague andcherished friend who fulfilled his objective of leaving the world abetter place, rest in peace.

Acknowledgment
We express our sincerest gratitude to Avi’s wife, Anat BarCohen, for providing input on our paper and additional material
about Avi’s life outside of our technical community.
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gargantuan (in their significance, usefulness, comprehensiveness,details and size) publications, Avi was deeply involved with several flourishing, extremely popular series of individual volumes,i.e., World Scientific Series in Advanced Integration and Packaging (a series of individual volumes, co-edited with Profs. Ricky
Lee and Bongtae Han) [19]—with a particular focus on 2.5D and
3D form factors—which, according to Avi’s vision, has provided
a “technology commons” for the packaging community, a place
where ideas can be articulated, examined, and disseminated rapidly and efficiently through both print and electronic media, andWorld Scientific Series in Emerging Technologies [20], in which
Avi had aspired to offer readers insightful explorations of themost exciting and compelling emerging technologies with thepotential to strongly impact diverse aspects of life on our planet.
Finally, true to his commitment to both research and education,
just last month Avi decided to branch out this core series ofresearch publications into an educational track as well, thus ensuring that both students and lecturers could benefit from having aforum where they can find lectures and lecture notes for courses
on “disruptive new technologies of the future”—and so a separate
World Scientific Series of Lectures in Emerging Technologies [21]was born.
Societal Contributions and Awards. Avi’s contributions in the
micro-electronics packaging communities in IEEE and ASME
were guided by a well-blended combination of pragmatic, technically deep and aspirational streams of thinking. It is important tounderstand the evolution of the field to better appreciate his influence. The value of computation in elucidating physical (including
heat transfer) phenomena, both through detailed modeling andcorrelation of theory with experiment, was quite well understoodby the sophisticated academics and industrial practitioners of the
mid to-late 1980s. However, beginning in the 1990s, personal
computing was starting to make its effects felt and Moore’s Law
enabled increasingly broader proliferation of computers for morethan technical use. This proliferation drove increased focus
on semiconductor and packaging technology development andhigh-volume manufacturing. Thermal management of microelectronics was one of the greatly challenging aspects ofpackaging and Avi’s technical contributions in this area areinvaluable. What is most impressive about his work is the emphasis on practical implementations of technically sound ideas. There
was also a great need to build a strong micro-electronics packaging community and to train next generations of engineers toensure the continued evolution of packaging. Avi’s academic andindustrial background helped him set comprehensive directions
and positively influence the growth of the thermal management
and packaging communities in IEEE and ASME. In ASME, hehelped shape the Electronics and Photonics Division and worked
with leaders in industry and academia to develop the InterPACK
conference. He, along with Peter Engel, Ephraim Suhir and others,
helped InterPACK achieve its current definition and stature. He
also established deep connections with industry leaders such as
Dr. Nasser Grayeli, and with their help developed the InterPACK
industrial advisory board. This board attracted industry sponsorship that was used to greatly enhance student participation.
InterPACK has become a primary venue for driving progress inthermal management, reliability, thermo-mechanically robust
designs, materials-mechanics interactions and photonics, strengthening links with other ASME communities and tying them withthe semiconductor industry.
Avi’s influence in IEEE was similarly powerful in numerous
ways. He started the ITherm Conference series in 1988 as a companion conference to the broader ECTC conference. This helped
emphasize the need for and value of thermal engineering in
micro-electronics packaging and the enduring popularity of thisconference is a testament to Avi’s vision. Avi represented the EPS(Electronics Packaging Society) formerly known as the Components Packaging and Manufacturing Technology Society (CPMT)
as a Distinguished Lecturer, delivering impactful lectures on thermal management across the globe. He served as Editor-in-Chief

Ivan Catton
University of California,
Los Angeles,
420 Westwood Plaza Room 43-132,
Engineering IV,
Los Angeles, CA 90095
e-mail: catton@g.ucla.edu

Marc Hodes
Tufts University,
200 College Avenue,
Medford, MA 02155
e-mail: marc.hodes@tufts.edu
Ravi Mahajan
Intel Corporation,
5000 West Chandler Blvd,
Chandler, AZ 85226
e-mail: ravi.v.mahajan@intel.com

Terry Simon
University of Minnesota,
111 Church Street SE,
Minneapolis, MN 55455
e-mail: simon002@umn.edu

Timothy Fisher
Department of Mechanical and Aerospace Engineering,
University of California, Los Angeles,
Los Angeles, CA 90095
e-mail: tsfisher@ucla.edu
Portonovo Ayyaswamy
University of Pennsylvania,
Room No. 231, 220 S. 33rd Street,
Philadelphia, PA 19104
e-mail: ayya@seas.upenn.edu

Karl Geisler
3M,
Mail Stop 260-5-B-09,
St. Paul, MN 55144
e-mail: kjgeisler@mmm.com
Michael Ohadi
Department of Mechanical Engineering,
University of Maryland,College Park, MD 20740
e-mail: ohadi@umd.edu
Joseph Maurer
MBO Partners,
2540 South Arlington Mill Dr. Unit B,
Arlington, VA 22206
e-mail: jjm9u@virginia.edu
David Altman
Raytheon,
528 Boston Post Road,
Sudbury, MA 01776
e-mail: david_h_altman@raytheon.com
Jim Wilson
Raytheon,
13510 N Central Expressway,
Dallas, TX 75243
e-mail: jsw@raytheon.com
Gennady Ziskind
Ben Gurion University,
P.O.B. 653,
Beer-Sheva 84105, Israele-mail: gziskind@bgu.ac.il
Mark Spector
Office of Naval Research,
875 N. Randolph Street,
Arlington, VA 22203-1995
e-mail: mark.spector@navy.mil

030101-6 / Vol. 143, MARCH 2021

Boravoje Mikic
Massachusetts Institute of Technology,
Room 5-214, Massachusetts Avenue,
Cambridge, MA 02139
e-mail: mikic@mit.edu

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Transactions of the ASME

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Zvi RuderWorld Scientific Press,
9501 Woodington Ct,
Cary, NC 27518
e-mail: zviruder@wspc.com

Vijay Dhir
University of California,
Los Angeles,
7400 Boelter Hall,
Los Angeles, CA 90095
e-mail: vdhir@seas.ucla.edu

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Journal of Heat Transfer

MARCH 2021, Vol. 143 / 030101-7