Prof. Trifon joined the Faculty of Industrial Engineering and Management at Technion in 1961/2, as the first regular appointment in the economics program. Prior to that, he did post-doctoral work in Canada. In 1965/6 he was Guest of the Institute at M.I.T., spent 1973/4 as Distinguished Professor in Manitoba, Canada, was a Visiting Professor at the University of Michigan (1981/2), and spent three full sabbaticals at Columbia University, New York (1986/7, 1989/90, 1994/5). Prof. Trifon spent one semester visits to Newcastle University, Australia (1971) and to the International Development Center of Japan in Tokyo (1974). He was also a Senior Researcher for the Asian Institute in Bangkok, for industrial development work both in India and Thailand (1968, 1970). At Technion, Prof. Trifon was Head of Industrial Engineering and Management (1963/4) and later Dean of that Faculty (1970--1972). He was also the first Head and a founder of the Economics degree programs at Technion, and the first Chairman and a founder of the Economics Department at Haifa University. He was also for some years Head of the Industrial Management Area at Technion (1982--1985, 1991--1992). He is a member of INFORMS, the American Economic Association, the Israel Economic Society, The O.R. Society of Israel and the International Labor Relations Association
Prof. Trifon's research and professional interest is mostly in the application of microeconomic theory to managerial and public decisions. His main fields of activity were consecutively in optimal land use and transportation planning, industrial conflicts and arbitration, and portfolio planning and evaluation. The work on land-use introduced Linear Programming into the field of Urban Planning (Trifon and Mazor, Trifon and Livnat), applied extensively later by Mazor, both in Israel and abroad. The work on transportation, involving the development of a heuristic algorithm for school busing design, led to the computerization of all rural school busing, and some urban, in Israel, including optimal routing (Trifon and Gafni). The work on industrial conflicts grew out of Prof. Trifon's involvement as an arbitrator in major labor disputes and membership in the Institute for Arbitration in the Public Sector in Israel. The project tries to model the behavior of the parties at conflict as a function of the arbitrator's code, stated or implied. For the objective of reduced militancy, some codes can be ranked more desirable than others (Trifon and Landau, Trifon, Harel and Parvari). Prof. Trifon's current work relates to performance evaluation of international portfolios. Capital can now increasingly move across borders, allowing investors new diversity at the cost of new currency risks. In order to evaluate the management of international portfolios, one needs both theory and measurement of "systematic risks" over national exchanges and currencies. This project tries to reach a meaningful definition of such systematic risk and assess it statistically. At this stage two graduate projects were output within this framework (Dominitz, Hausner). As portfolio valuation theory requires markets to be "efficient", tests of efficiency must precede other measurements. For one test, the project tries to predict short-term fluctuations in high-tech industries from fluctuations of their traded stocks.