(Speech delivered by Dr. Dwight Duffus)

Dr. Rival joined the University of Ottawa in 1986 as a professor of computer science and mathematics, and was chair of the Department of Computer Science between 1988 and 1991.

Upon his arrival at the university he started the algorithms research group which very quickly became an active and productive group.

Most of his research work became more focused on the application side of the theory of ordered sets. Being in a computer science department surely did influence this shift, but more importantly he believed that applications are crucial for the flourishing of the theory. He wanted to make "Order Theory" accessible to the outside world through very specific applications.

Dr. Rival was well known for his love for the arts and he surely had good taste. He took pride in the beautiful diagrams he created in lectures and in print -- he spent long hours drawing clean, aesthetically pleasing diagrams. Indeed, the aesthetics of drawing hierarchical structures or diagrams became a major focus in his research work. Still he saw the need to find applications that should reach the public and more specifically the university population at large and where our scientific knowledge is used at maximum.

Of course he knew that this wouldn’t be an easy task, and would surely require a different set of abilities than research in pure mathematics.

In 1994 the idea for the first software was drafted. Since then, several innovative ideas around that software developed. Ivan was very proud of this software, and as he wished, the science in an area where he was a pioneer, was beautifully used.

Very successful years as an entrepreneur did follow, several software systems were developed with their main applications to the university population -- today these are being used all over the world.

The task of introducing innovative ideas to the general public is far from easy, but with his incredible energy, his persistence, focus and his sense of mission, he was able once again to achieve this goal.

In the last years of his life, as an entrepreneur, Ivan showed vision, warmth and an ease in talking and interacting with people, and the ability to make tough decisions when needed. Simply the right skills for a scientific leader and a successful entrepreneur. He accomplished so much in his life, with incredible speed. Ivan did not waste time.

As my professor, colleague, friend, and business partner it has always been for me a learning experience. You will always be in our minds. Good Bye.