őren started his working life in the industry in 1963 as systems engineer for ibm türk in istanbul, where he coordinated effort in the textile industry, and in education. in 1970, he started his academic career as assistant professor at the computer science department of the university of ottawa, where in 1981 he became full professor. he has been visiting professor at national space activities commission of brazil, sao jose dos campos, são paulo, brazil in 1971; at the institute of systems sciences, johannes kepler university, linz, austria in 1983; at the middle east technical university, ankara, turkey in 1983 and 1991; at the university of vienna, austria in 1984–85; and at the université paul cézanne – aix marseille 3, marseille since 2004.