Dr. Shen received his Ph.D. from Queens University, Canada in 1998. He has been working on combinatorial matrix theory, a subject which connects linear algebra with combinatorics. He has proved a few conjectures on the exponents of primitive matrices. Dr. Shen's current research is focused on graph theory and algorithm. He has made substantial contributions to the research of a number of conjectures, including the Caccetta-Haggkuist conjecture (1978), on the cycle structure of directed graphs. He proved the up-to-date strongest result to support the Frame-Stewart conjecture (1941) on the towers of Hanoi. Dr. Shen plans to extend his research to networks design and probabilistic methods in discrete mathematics.