Ottawa - Carleton Combinatorics and Optimization Seminar

Talks this term (Winter 2007)

Usually every other Friday at 2:00pm, either at Carleton University or the University of Ottawa, depending on the location of the Joint Colloquium.

         Speaker: Jason Gao, Carleton University        
         Title:  Spanning walks of bounded  "degrees”

        Abstract: A k-walk in a graph G is a closed walk in G which visits each vertex at least once and at most k times. K-walks are natural extensions of Hamiltonian cycles (a 1-walk is simply a Hamiltonian cycle). In this talk, we review some known results about k-walks. We will discuss about a recent result by Kaiser-Kuzel-Li-Wang about the existence of k-walks in
bridgeless graphs with maximum degree 2k.

          Speaker: Li Dong, Carleton University        
        
          Speaker: Amir Akbary

           Speaker: Kevin Cheung, Carleton University

          Speaker: Mateja Sajna,  University  of Ottawa


          Speaker: Steven Wang, Carleton University


Fall 2006

          First speaker: Gabriel Verret (University of Ottawa)                                    
          Title: Shifts in Cayley Graphs

         Second speaker: Mateja Sajna (University of Ottawa)
         Title: On Regular and Vertex-Transitive  Self-Complementary Hypergraphs

           Speaker: Kevin Cheung (Carleton University)

          Title: Towards an implementation of an outer appromixation algorithm for large-scale concave minimization over a polytope

          Speaker: Jason Gao (Carleton University)

          Title: Some Interesting Properties of Circuit Graphs

           Speaker: Brett Stevens (Carleton University)

          Title: The Solution to the Shannon Switching Game

          Speaker: Arkadii Slinko (University of Auckland)

          Title: Optimal Lobbying in Multiple Referenda

          Speaker: Steven Wang (Carleton University)

          Title:  On a new class of permutation polynomials over finite fields
 

Winter 2006

          Speaker: Brett Stevens (Carleton University)

          Title: Maximally Pair Separated Round Robin Tournaments: Ordering the Blocks of a Design

          Speaker: Primoz Potocnik (University of Ljubljana)
         
          Title: Colorability and related properties of vertex-transitive graphs

           Speaker: Peter Danziger (Ryerson University)

          Title: Hill Climbing to Pasch Valleys

           Speaker: Andrea Burgess (University of Ottawa)
         
          Title: Colouring even cycle systems

          Speaker: Youngbin Choe (Pohang University of Science and Technology)

          Title: Counting vertices and cubes in Buneman graphs (or median graphs)
        
          Speaker: Guang Gong (University of Waterloo)

          Title: WG Steam Cipher

           Speakers: Ariane Masuda, Li Dong, Jordan Bell, Shai Mor, Megan Dewar, Jason Lobb (all Carleton University)

          Title: Graduate student talks for the Ontario Combinatorics Workshop

           Speakers: Andrea Burgess, Paul Elliott Magwood, Shonda Gosselin, Gabriel Verret, Latifa Zekaoui  (all University of Ottawa)

          Title: Graduate student talks for the Ontario Combinatorics Workshop

Fall 2005

        Speaker: Zhicheng (Jason) Gao

        Title: Finding long cycles in 3-connected graphs.

            Speaker: Mateja Sajna

            Title:  Homogeneously almost self-complementary graphs and self-complementary two-graphs

          Speaker: Vaclav Linek

        Title: Generalizations of Skolem Sequences

          Speaker:  Shonda Gosselin

          Title: Regular Two-Graphs and Equiangular Lines

           Speaker: Alan Ling

        Title:  The existence of resolvable graph designs

           Speaker:  Rodrigo Hausen

          Title: Genome Rearrangements

Winter 2005

Speaker: Kevin Vander Meulen (Redeemer University College) 
Title: Clique Partitions of Distance Graphs
Speaker: Reza Naserasr, Royal Military College
Title: The four colour theorem and graph homomorphisms
The talk by Guang Gong has been cancelled due to unforeseen circumstances.
Speaker: Marcel Turcotte, University of Ottawa
Title: Two problems related to RNA secondary structure determination
Speaker: Ben Steinberg, Carleton University
Title: Subword counting and upper triangular matrices over finite fields

Speaker: Paul Elliott - Magwood, University of Ottawa
Title: The Integrality Gap of the Asymmetric Travelling Salesman Problem

Speaker: Steven Wang, Carleton University
Title: Permutation binomials over finite fields


Talks in the Fall 2004

Speaker: Francesco Barioli, Carleton University
Title: Inverse Eigenvalue Problem for Symmetric Matrices
Speaker: Mercedes Rosas, York University
Title: Invariants and covariants of the symmetric group, a noncommutative version
Speaker: Karen Meagher, University of Ottawa
Title:  Erdos-Ko-Rado theorems for uniform set partition systems
Speaker: Valerie Watts, Carleton University
Title: Fractional biclique covers and partitions of graphs
Speaker: Sara Faridi, University of Ottawa
Title:  Questions and Constructions in Higher Dimensional Graph Theory
Speaker: Mateja Šajna, University of Ottawa
Title:  Almost Self-complementary Graphs


Past talks