CMS/SMC
CanaDAM 2011
University of Victoria, May 31 - June 3, 2011 www.cms.math.ca//2011
Program        

Schedule - All Other Talks

Please note that schedules are subject to change without notice, particularly changes within a given session.

Algebraic Combinatorics (IM6)
Org: Mike Zabrocki (York University)
This minisymposia will have speakers who research areas of algebra and combinatorics. Topics might include representation theory, algebra and symmetric functions and the use of combinatorial tools to solve problems in these areas.
 
Friday June 3
10:10 - 10:35 Kurt Luoto (University of British Columbia), Quasisymmetric and noncommutative Schur functions, Cornett A121
10:40 - 11:05 Sara Faridi (Dalhousie University), Resolutions of monomial ideals, Cornett A121
11:10 - 11:35 Adriano Garsia (University of California San Diego), Combinatorial properties of Parking Functions and Diagonal Harmonics, Cornett A121
11:40 - 12:05 Angela Hicks (University of California San Diego), Parking Function Properties Suggested by the Haglund-Morse-Zabrocki Conjecture, Cornett A121
12:10 - 12:35 Nantel Bergeron (York University), An Hopf Monoid of supercharacter, Cornett A121
 
Algebraic Graph Theory (CT12)
 
Thursday June 2
15:15 - 15:40 Satyanarayana Reddy Arikatla (Indian Institute of Technology Kanpur, India), Relationships among some graph algebras on some graph classes, MacLaurin D114
15:45 - 16:10 Danielle Cox (Dalhousie University), Roots of Graph Polynomials, MacLaurin D114
16:15 - 16:40 Elissa Ross (York University), Finite motions from periodic frameworks with additional symmetry, MacLaurin D114
16:45 - 17:10 Robert Šámal (Charles University), Highly arc transitive digraphs, MacLaurin D114
 
Algorithms and Complexity I (CT3)
 
Tuesday May 31
15:15 - 15:40 Amir Hedayaty (Simon Fraser University), On the complexity of approximate counting of CSPs, MacLaurin D101
15:45 - 16:10 Khalegh Mamakani (Dept. of Computer Science, University of Victoria, Canada), Generating All Simple Convexly-Drawable Polar-Symmetric 6-Venn Diagrams, MacLaurin D101
16:15 - 16:40 Johan Oppen (Molde University College), Connected sequences, MacLaurin D101
16:45 - 17:10 Marek Tesar (Charles University, Prague), Locally injective homomorphism to the simple Weight graphs, MacLaurin D101
17:15 - 17:40 Aaron Williams (Carleton University), New Constructions for Universal Cycles and de Bruijn Cycles, MacLaurin D101
 
Algorithms and Complexity II (CT13)
 
Thursday June 2
15:15 - 15:40 Kathie Cameron (Wilfrid Laurier University), Rainbow Matchings in Bipartite Graphs, MacLaurin D103
15:45 - 16:10 Christopher Duffy (University of Victoria), The Firefighter Problem - Weights and Sets, MacLaurin D103
16:15 - 16:40 Jessica Enright (University of Alberta), Set Representation Graph Games, MacLaurin D103
16:45 - 17:10 Elaine Eschen (West Virginia University), On deciding whether the distinguishing chromatic number of a graph is at most two, MacLaurin D103
17:15 - 17:40 Donovan Hare (University of British Columbia, Okanagan Campus), A Note on the Hardness of Graph Diameter Augmentation Problems, MacLaurin D103
 
Applications of Graph Theory To Chemistry I (CM15)
Org: Patrick Fowler (University of Sheffield)
This session and the following one explore applications of Graph Theory to Chemistry.

Part I: Conduction and aromaticity in carbon networks, and computer generation of conjectures about graph parameters and chemical invariants.

 
Thursday June 2
10:10 - 10:35 Patrick Fowler (University of Sheffield), Currents in molecules, Cornett A229
10:40 - 11:05 Milan Randic (National Insitute of Chemistry, Ljubljana), Graph Theoretical Models of Ring Currents in Conjugated Hydrocarbons, Cornett A229
11:10 - 11:35 Irene Sciriha (University of Malta), Interlacing and Omni-Conduction in Single Molecules, Cornett A229
11:40 - 12:05 Craig Larson (Virginia Commonwealth University), Conjecturing with GrInvIn, Cornett A229
 
Applications of Graph Theory to Chemistry II (CM18)
Org: Wendy Myrvold (University of Victoria)
This session and the previous one explore applications of Graph Theory to Chemistry.

Part II: Fullerenes and algorithms for generating graphs representing classes of chemical molecules.

 
Thursday June 2
15:15 - 15:40 Wendy Myrvold (University of Victoria), Independent Sets of Fullerenes, Cornett A229
15:45 - 16:10 Nico Van Cleemput (Ghent University), CaGe - A Chemical and Abstract Graph Environment, Cornett A229
16:15 - 16:40 Dong Ye (West Virginia University), Resonance in Fullerenes, Cornett A229
16:45 - 17:10 Elizabeth J. Hartung (Syracuse University), Fullerene Parameters: A Colorful Approach, Cornett A229
 
Applications of Matroid Theory in Coding Theory I (CM22)
Org: Irene Márquez Corbella (University of Valladolid)
This minisymposium is aimed at bringing together researchers from all fields related to the applications of matroid theory in coding theory. Since much of the work related to this subject is still ongoing, the minisymposium will provide a stimulating atmosphere where experts will be able not only to report their recent results, but also to propose new guidelines of research and discuss open questions. It will also give us the opportunity to present the interest and the potential applications of this topic to the rest of the scientific community.
 
Friday June 3
10:10 - 10:35 Thomas Britz (University of New South Wales (Australia)), Duality theorems for graphs, codes, and matroids., Cornett A229
10:40 - 11:05 Relinde Jurrius (Eindhoven University of Technology (Netherlands)), Truncation formulas for invariant polynomials of matroids and geometric lattices., Cornett A229
11:10 - 11:35 Gary Gordon (Lafayette College), Generalizations of matroid duality, Cornett A229
11:40 - 12:05 Graham Farr (Monash University (Australia)), Transforms, minors, binary functions and generalised Tutte polynomials, Cornett A229
 
Applications of Matroid Theory in Coding Theory II (CM24)
Org: Edgar Martínez Moro (University of Valladolid)
This minisymposium is aimed at bringing together researchers from all fields related to the applications of matroid theory in coding theory. Since much of the work related to this subject is still ongoing, the minisymposium will provide a stimulating atmosphere where experts will be able not only to report their recent results, but also to propose new guidelines of research and discuss open questions. It will also give us the opportunity to present the interest and the potential applications of this topic to the rest of the scientific community.
 
Friday June 3
15:15 - 15:40 Irene Márquez Corbella (University of Valladolid (Spain)), Matroid decomposition and minimal codewords II, Cornett A229
15:45 - 16:10 Pradeep Sarvepalli (University of British Columbia (Vancouver)), Quantum codes and symplectic matroids, Cornett A229
16:15 - 16:40 Keisuke Shiromoto (Kumamoto University (Japan)), Codes over rings and matroids., Cornett A229
16:45 - 17:10 Edgar Martínez Moro (University of Valladolid), Matroid decomposition and minimal codewords, Cornett A229
 
Asymptotic Enumeration (CT8)
 
Wednesday June 1
15:15 - 15:40 Aubrey Blecher (University of Witwatersrand, Johannesburg, South Africa), Compositions of positive integers n viewed as alternating sequences of increasing/decreasing partitions., MacLaurin D103
15:45 - 16:10 Samuel Johnson and Steve Melczer (Simon Fraser University), Asymptotic analysis of walks with small steps in the quarter plane., MacLaurin D103
16:15 - 16:40 David Laferrière (Carleton University), Asymptotics of Decomposable Combinatorial Structures with Components of Alg-Log Type, MacLaurin D103
16:45 - 17:10 Cristiane M. Sato (University of Waterloo), Asymptotic enumeration of sparse 2-connected graphs, MacLaurin D103
 
Bioinformatics (IM3)
Org: Miklos Csuros (University of Montreal)
The mini-symposium addresses current problems in the mathematics of molecular sequence analysis. Advanced technologies for sequencing DNA and proteins drive increasingly more comprehensive studies about the diversity of molecular sequences across living organisms. Talks in this mini-symposium touch on fundamental mathematical and algorithmic issues arising at different stages along the analysis pipeline between sequence data production and their biological applications.
 
Wednesday June 1
15:15 - 15:40 Cedric Chauve (Simon Fraser University), Mapping ancestral genomes with massive gene loss: a matrix sandwich problem, Cornett A121
15:45 - 16:10 Lucian Ilie (University of Western Ontario), Fast combinatorial computation of good seeds for genome alignment, Cornett A121
16:15 - 16:40 Bin Ma (University of Waterloo), Algorithms for Protein/Peptide Sequencing with Mass Spectrometry, Cornett A121
16:45 - 17:10 Paul Medvedev (University of California San Diego / University of Toronto), Paired de Bruijn Graphs: a Novel Approach for Incorporating Mate Pair Information into Genome Assemblers, Cornett A121
17:15 - 17:40 Juraj Stacho (Caesarea Rothschild Institute, University of Haifa), Unique perfect phylogeny is NP-hard, Cornett A121
 
Broadcasting and Domination (CT14)
 
Friday June 3
10:10 - 10:35 Lino Demasi (Simon Fraser University), Domination in Plane Triangulations, MacLaurin D101
10:40 - 11:05 Hayk Grigoryan (Concordia University), On graphs with diametral broadcast time, MacLaurin D101
11:10 - 11:35 Karen Seyffarth (University of Calgary), The Dominating Graph, MacLaurin D101
11:40 - 12:05 Hocine Boumediene Merouane (University Saad Dahlab of Blida, Algeria), The dominator partition in hypercubes, MacLaurin D101
12:10 - 12:35 Scott Lunney (University of Victoria), Broadcasts and Domination in Trees, MacLaurin D101
 
Chromatic Numbers of Graphs (CM11)
Org: Joan Hutchinson (Macalester College)
Many variations on the classic chromatic number of a graph have emerged in recent years, sometimes to illuminate that chromatic number and other times for the sake of the new variation and its applications. In this mini-symposium the variations of list-coloring, co-chromatic number, subchromatic number, and 1-defective colorings will be presented, along with the interaction between colorings as measured by the canonical coloring graph of a graph.
 
Wednesday June 1
15:15 - 15:40 John Gimbel (University of Alaska at Fairbanks), Defective chromatic and cochromatic numbers, Cornett A120
15:45 - 16:10 Ruth Haas (Smith College), The Canonical Coloring Graph, Cornett A120
16:15 - 16:40 Joan Hutchinson (Macalester College), List-coloring extension results for planar graphs, Part I, Cornett A120
16:45 - 17:10 Michelle Lastrina (Iowa State University), List-coloring extension results for planar graphs, Part II, Cornett A120
17:15 - 17:40 Karen L. Collins (Wesleyan University, Middletown CT 06459-0128), Bounds on the distinguishing chromatic number of a graph, Cornett A120
 
Colourings, Independence, and (Forbidden) Subgraphs (CM25)
Org: Ingo Schiermeyer (Technical University Freiberg, Germany)
There is a great variety of results for vertex-colourings and independence in graphs in terms of forbidden subgraphs. One of the most well-known is the Strong Perfect Graph Theorem. Edwards has shown the following approach: If a graph $G$ has a dominating set $D$, then $3$-colourability can be decided in time $O(3^{|D|} \cdot |E(G)|)$. Using a result of Bacs\'o and Tuza that a $P_5$-free graph has a dominating clique or a dominating $P_3,$ Randerath and Schiermeyer showed that $3$-colourability can be decided in polynomial time for $P_5$-free and $P_6$-free graphs.
 
Friday June 3
15:15 - 15:40 Ingo Schiermeyer (Technical University Freiberg, Germany), Graphs with rainbow connection number two, Cornett A120
15:45 - 16:10 Vadim Lozin (University of Warwick, UK), Vertex 3-colorability of claw-free graphs, Cornett A120
16:15 - 16:40 Anja Kohl (Technical University Freiberg, Germany), Investigating the $b$-chromatic number of bipartite graphs by using the bicomplement, Cornett A120
16:45 - 17:10 Stephan Matos Camacho (Technical University Freiberg, Germany), Stars in Minimum Rainbow Subgraphs, Cornett A120
 
Combinatorial Designs, Codes and Graph Factors (CT1)
 
Tuesday May 31
10:10 - 10:35 Atif Abueida (University of Dayton), The spectrum of non-polychromatic equitable edge colored Steiner Triple Systems, MacLaurin D101
10:40 - 11:05 Melissa Keranen (Michigan Technological University), GDDs with two groups and block size 6 with fixed block configuration, MacLaurin D101
11:10 - 11:35 Nidhi Sehgal (Auburn University), $6$-cycle system of the cartesian product $K_x \times K_y$ covering $2$-paths in $K_{x,y}$, MacLaurin D101
11:40 - 12:05 Padmapani Seneviratne (American University of Sharjah), Codes from multipartite graphs and permutation decoding, MacLaurin D101
12:10 - 12:35 China Venkaiah Vadlamudi (C R Rao Advanced Institute of Mathematics, Statistics, and Computer Science), Sequentially Perfect 1-Factorization and Cycle Structure of Patterned Factorization of $K_{2^{n}}$, MacLaurin D101
 
Combinatorial Optimization (IM1)
Org: Mohit Singh (McGill University)
Combinatorial optimization problems usually come in two flavours, ones that can be solved in polynomial time and others that are NP-hard. This session will feature recent developments on problems from both classes. For the former, the talks will present fast algorithms for some fundamental combinatorial optimization problems. For the problems that are NP-hard, the talks will present approximation algorithms that are efficient and solve the problem approximately with a good guarantee on the solution.
 
Tuesday May 31
10:10 - 10:35 Bruce Shepherd (McGill University), Maximum Edge Disjoint Paths, Cornett A121
10:40 - 11:05 Dan Golovin (California Institute of Technology), Adaptive Submodularity: A New Approach to Active Learning and Stochastic Optimization, Cornett A121
11:10 - 11:35 Tom McCormick (University of British Columbia), A Combinatorial Polynomial Algorithm for Weighted Abstract Cut, Cornett A121
11:40 - 12:05 Glencora Borradaile (Oregon State University), Finding all min st-cuts in planar graphs, Cornett A121
12:10 - 12:35 Guyslain Naves (McGill University, Montreal), Mader-Mengerian graphs (joint work with Vincent Jost, École Polytechnique, France)., Cornett A121
 
Computational Complexity (IM7)
Org: Venkatesh Srinivasan (University of Victoria)
Computational complexity is a central field of research in theoretical computer science that focuses on classifying computational problems based on the amount of resources they require. Examples of such resources include time, space, communication, amount of randomness and so on. This field has introduced many interesting computational models to study such problems and has been the source of amazing results in the recent years leading to a deeper understanding of the power and limitations of efficient computation.
 
Friday June 3
10:10 - 10:35 Paul Beame (University of Washington), Making Branching Programs Oblivious Requires Superlogarithmic Overhead, Cornett A120
10:40 - 11:05 Valerie King (University of Victoria), Scalable Distributed Computing Using Averaging Samplers and Bit-fixing Random Sources, Cornett A120
11:10 - 11:35 David Kirkpatrick (University of British Columbia), Finding treasure in trees, Cornett A120
11:40 - 12:05 Anup Rao (University of Washington), Towards Coding for Maximum Errors in Interactive Communication, Cornett A120
12:10 - 12:35 Venkatesh Srinivasan (University of Victoria), Rewriting of Visibly Pushdown Languages for XML Data Integration, Cornett A120
 
Convexity and Metric Graph Theory I (CM12)
Org: José Cáceres (Universidad de Almería, Almería (Spain))
In a network, the most natural question about two vertices is whether or not they are connected, and the second one could be asking for the distance between them. Thus the study of graphs as metric spaces has been always an important part of the field. This minisimposium and the following one intend to show those recent developments in metric frameworks as convexity that may lead to new perspectives on old questions.
 
Wednesday June 1
15:15 - 15:40 Robert Bailey (Department of Mathematics and Statistics University of Regina Regina, SK Canada), A matrix method for resolving sets in Johnson graphs, Cornett A229
15:45 - 16:10 Alberto Márquez (Departamento de Matemática Aplicada I Universidad de Sevilla Sevilla, Spain), Some question about metric dimension of some families of graphs, Cornett A229
16:15 - 16:40 Mercè Mora (Departament de Matemàtica Aplicada II Universitat Politècnica de Catalunya Barcelona, Spain), Geodetic and hull numbers in strong product graphs, Cornett A229
16:45 - 17:10 José Cáceres (Departamento de Estadística y Matemática Aplicada Universidad de Almería Almería, Spain), Metric dimension in infinite but locally finite graphs, Cornett A229
17:15 - 17:40 Michael Young (Iowa State University), Disjoint Homometric Sets in Graphs, Cornett A229
 
Convexity and Metric Graph Theory II (CM19)
Org: José Cáceres (Universidad de Almería, Almería (Spain))
In a network, the most natural question about two vertices is whether or not they are connected, and the second one could be asking for the distance between them. Thus the study of graphs as metric spaces has been always an important part of the field. This minisimposium and the previous one intend to show those recent developments in metric frameworks as convexity that may lead to new perspectives on old questions.
 
Thursday June 2
15:15 - 15:40 Mitre Dourado (COPPE Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ Brazil), Complexity aspects of graph convexity, Cornett A120
15:45 - 16:10 Morten Nielsen (Department of Mathematics and Statistics Thompson Rivers University Kamloops, BC Canada), Helly theorems for convex sets in graphs, Cornett A120
16:15 - 16:40 Ignacio M Pelayo (Departament de Matemàtica Aplicada III Universitat Politècnica de Catalunya Barcelona, Spain), Dominating location in graphs, Cornett A120
16:45 - 17:10 Ortrud R Oellermann (Department of Mathematics and Statistics University of Winnipeg Winnipeg, MB Canada), Separation Properties for 3-Steiner and 3-Monophonic Convexity in Graphs, Cornett A120
 
Covering Arrays, Generalizations and Software Testing Applications I (CM4)
Org: Peter Danziger (Ryerson University), Lucia Moura (University of Ottawa) and Brett Stevens (Carleton University)
Covering arrays are combinatorial designs that generalize orthogonal arrays, and have been more intensively studied in the past few years. Under the name of test suites for pairwise or combinatorial testing, they have proved very effective for testing hardware and software. This two-part mini-symposium showcases the interplay of covering array theory and applications. It shows how the applications motivated the study of generalizations of covering arrays with interesting ties to other areas of discrete mathematics (graph and hypergraph theory, graph homomorphisms, combinatorial group testing, probability theory). It also overviews current software testing research that supports the use of covering arrays.
 
Tuesday May 31
15:15 - 15:40 Lucia Moura (University of Ottawa), Covering arrays and generalizations, MacLaurin D110
15:45 - 16:10 Elizabeth Maltais (University of Ottawa), Covering arrays avoiding forbidden edges, MacLaurin D110
16:15 - 16:40 Myra Cohen (University of Nebraska - Lincoln), GUI Interaction Testing: Using Covering Arrays to Provide Context in Software Testing, MacLaurin D110
16:45 - 17:10 Dan Hoffman (University of Victoria), The Influence of Parameter Values in the Practical Application of Combinatorial Test Generation, MacLaurin D110
17:15 - 17:40 Gary Bazdell (Carleton University), Evaluating Single Approach Constructions for Arbitrary Strength 2 Covering Arrays, MacLaurin D110
 
Covering Arrays, Generalizations and Software Testing Applications II (CM20)
Org: Peter Danziger (Ryerson University), Lucia Moura (University of Ottawa) and Brett Stevens (Carleton University)
Covering arrays are combinatorial designs that generalize orthogonal arrays, and have been more intensively studied in the past few years. Under the name of test suites for pairwise or combinatorial testing, they have proved very effective for testing hardware and software. This two-part mini-symposium showcases the interplay of covering array theory and applications. It shows how the applications motivated the study of generalizations of covering arrays with interesting ties to other areas of discrete mathematics (graph and hypergraph theory, graph homomorphisms, combinatorial group testing, probability theory). It also overviews current software testing research that supports the use of covering arrays.
 
Thursday June 2
15:15 - 15:40 Anant Godbole (East Tennessee State University), Improving covering array bounds using alternative probability models, MacLaurin D110
15:45 - 16:10 Nevena Francetic (University of Toronto), Covering Arrays with Row Limit, MacLaurin D110
16:15 - 16:40 Brady Garvin (University of Nebraska -- Lincoln), Side Constraints and Covering Array Generation by Simulated Annealing, MacLaurin D110
16:45 - 17:10 Sebastian Raaphorst (University of Ottawa), Variable Strength Covering Arrays, MacLaurin D110
 
Cryptography (IM2)
Org: Bruce Kapron (University of Victoria)
There are a now a variety of well-founded mathematical approaches to understanding security in cryptographic systems. Techniques from algorithms and computational complexity, formal logic, and information theory have all been successfully used in providing a more rigorous foundation for the study of cryptography. This minisymposium will explore cryptographic security from these varied perspectives.
 
Tuesday May 31
15:15 - 15:40 Bruce Kapron (University of Victoria), Co-induction and Computational Semantics for Public-key Encryption with Key Cycles, Cornett A121
15:45 - 16:10 Yassine Lakhnech (Université Joseph Fourier (Grenoble 1)), Computational Indistinguishability Logic, Cornett A121
16:15 - 16:40 Rei Safavi-Naini (University of Calgary), cryptographic keys from noisy channels, Cornett A121
16:45 - 17:10 Andre Scedrov (University of Pennsylvania), Bounded memory Dolev-Yao adversaries, Cornett A121
 
Designs and Codes I (CM13)
Org: Peter Dukes (University of Victoria), Esther Lamken (California Institute of Technology) and John van Rees (University of Manitoba)
Codes and Designs have many applications to statistics, communications and engineering. They are also an important component to pure mathematics, especially geometry. This mini-symposium plans to invite many of the top researchers in the field to present their latest results. We hope to have two sessions of 5 speakers each.
 
Wednesday June 1
15:15 - 15:40 Doug Stinson (U. of Waterloo), A Unified Approach to Combinatorial Key Predistribution Schemes for Sensor Networks, MacLaurin D110
15:45 - 16:10 Clement Lam (Concordia University), A computer search for Projective Hjelmslev Planes of order 9, MacLaurin D110
16:15 - 16:40 Brett Stevens (Carleton University), Covering designs and Matroids, MacLaurin D110
16:45 - 17:10 Jeff Dinitz (University Of Vermont), Constructions for Retransmission Permutation Arrays, MacLaurin D110
17:15 - 17:40 John van Rees (U. of Manitoba), 3-Uniform Friendship Hypergraphs, MacLaurin D110
 
Designs and Codes II (CM16)
Org: Peter Dukes (University of Victoria)
This session is an extension of ``Designs and Codes I''. The focus is on combinatorial designs and error-correcting codes, with special emphasis on connections between those subjects.
 
Thursday June 2
10:10 - 10:35 Peter Dukes (University of Victoria), Injection Codes, MacLaurin D110
10:40 - 11:05 Hadi Kharaghani (University of Lethbridge), The Gramian of mutually unbiased Hadamard matrices, MacLaurin D110
11:10 - 11:35 Esther Lamken (California Institute of Technology), Existence results for Howell cubes, MacLaurin D110
11:40 - 12:05 David Pike (Memorial University of Newfoundland), Hamilton cycles in restricted block-intersection graphs, MacLaurin D110
12:10 - 12:35 Alex Rosa (McMaster University), Circulants as signatures of cyclic Steiner triple systems, MacLaurin D110
 
Discrete and Computational Geometry (IM8)
Org: Binay Bhattacharya (Simon Fraser University)
 
Friday June 3
15:15 - 15:40 Caoan Wang (Memorial University of Newfoundland), A note on Hamiltonian tetrahedralizations, Cornett A121
15:45 - 16:10 Ladislav Stacho (Simon Fraser University), Problems on Geometric Graphs, Cornett A121
16:15 - 16:40 David Kirkpatrick (University of British Columbia), Polygonal paths of bounded curvature, Cornett A121
16:45 - 17:10 Sue Whitesides (University of Victoria), Approaches to Hard (and Potentially Deep and Wet) Problems in Computational Geometry, Cornett A121
17:15 - 17:40 Binay Bhattacharya (Simon Fraser University), Application of computational geometry to network location problems, Cornett A121
 
Edge-Colouring and Structures on Line Graphs (CM5)
Org: Jessica McDonald (Simon Fraser University)
Different variations of edge-colourings are bound together by the structure of line graphs and the techniques that this structure suggests. Alternating paths play a vital role here, with current progress towards the famous Goldberg-Seymour Conjecture proceeding principally via the method of Tashkinov trees (a sophisticated selection of alternating paths). In this session we shall hear about such progress, as well as recent results on important variants of chromatic index, including circular chromatic index and acyclic list chromatic index.
 
Tuesday May 31
15:15 - 15:40 Diego Scheide (Simon Fraser University), Acyclic list edge-colourings of degenerate graphs, Cornett A120
15:45 - 16:10 Andrew King (Columbia University), Bounding the chromatic index: Exploiting and sidestepping structure, Cornett A120
16:15 - 16:40 Oguz Kurt (The Ohio State University), The rule trees and the cubic root bound on the chromatic index, Cornett A120
16:45 - 17:10 Jessica McDonald (Simon Fraser University), Kempe equivalence of edge colourings in (sub)cubic graphs, Cornett A120
17:15 - 17:40 Luis Goddyn (Simon Fraser University), Edge List Colouring of Planar Cubic Graphs, Cornett A120
 
Embeddings and Geometric Representations of Graphs (CM1)
Org: Debra Boutin (Hamilton College)
This mini-symposium will explore the connections between abstract graphs and geometry (broadly defined). Some of the topics that naturally arise in this area are: interval graphs (vertices correspond to intervals of the real line, edges to intersecting intervals) or rectangle visibility graphs (vertices correspond to rectangles in the plane, edges to rectangle that can \lq\lq see" each other), geometric graphs (straightline drawings of graphs in the plane), graphs embedded on surfaces (edges don't cross and are not necessarily straight).
 
Tuesday May 31
10:10 - 10:35 Dan Archdeacon (University of Vermont), The edge-ratio of geometric embeddings, Cornett A120
10:40 - 11:05 Andrew Beveridge (Macalester College), Directed Visibility Number for Planar Digraphs and Tournaments, Cornett A120
11:10 - 11:35 Sally Cockburn (Hamilton College), Permutations and Geometric Realizations of $K_{2,n}$, Cornett A120
11:40 - 12:05 Mark Ellingham (Vanderbilt University), Hamilton cycle embeddings of complete tripartite graphs, Cornett A120
12:10 - 12:35 Alice Dean (Skidmore College), Posets of Geometric Graphs, Cornett A120
 
Enumeration (CT4)
 
Tuesday May 31
15:15 - 15:40 Alejandro Erickson (University of Victoria), Enumerating Tatami Tilings, MacLaurin D114
15:45 - 16:10 Elizabeth McMahon (Lafayette College), Derangements of the facets of the $n$-cube, MacLaurin D114
16:15 - 16:40 Alois Panholzer (Vienna University of Technology), Some new results for deriving hook-length formulas for trees, MacLaurin D114
16:45 - 17:10 Jose Plinio Santos (UNICAMP-Universidade Estadual de Campinas), Bijections between lattice paths and plane partitions, MacLaurin D114
 
Exact Combinatorics with Applications in Physics (CM7)
Org: Marni MISHNA (Simon Fraser University)
Physics is a rich source of inspiration for discrete mathematics. This minisymposium will focus on combinatorial work related to physics which is exact in nature rather than purely statistical.

Such work can be quite varied both combinatorially and physically, but is unified in flavour and in the interplay of the fields. It is exciting because frequently not only does the physics inform the combinatorics, but also the combinatorics can be brought to bear nontrivially on interesting physical problems.

Important examples include renormalization Hopf algebras in quantum field theory and exact enumeration of self avoiding walks in polymer physics.

 
Wednesday June 1
10:10 - 10:35 Stu Whittington (University of Toronto), Directed walk models of polymers, Cornett A229
10:40 - 11:05 Karen Yeats (Simon Fraser University), Spanning forest polynomials and Feynman graph denominators, Cornett A229
11:10 - 11:35 Loic Foissy (Universite Reims), Systems of Dyson-Schwinger equations, Cornett A229
11:40 - 12:05 Chris Soteros (University of Saskatoon), Entanglement Complexity for Polygons in a Lattice Tube, Cornett A229
12:10 - 12:35 Philippe Nadeau (University of Vienna), Combinatorics of Fully Packed Loop configurations, Cornett A229
 
Extremal Combinatorics (CT5)
 
Tuesday May 31
15:15 - 15:40 Mahmud Akelbek (Weber State University), Various bounds on the scrambling index and the generalized scrambling index, MacLaurin D103
15:45 - 16:10 Sean McGuinness (Thompson Rivers University), Degree constrained subgraphs in a graph, MacLaurin D103
16:15 - 16:40 Mark Schurch (University of Victoria), On Graphs with Depression Three, MacLaurin D103
16:45 - 17:10 Ben Seamone (Carleton University), Variations of the 1,2,3-Conjecture, MacLaurin D103
17:15 - 17:40 Tamon Stephen (Simon Fraser University), A short proof that 4-prismatoids have width at most 4., MacLaurin D103
 
Extremal Graph Theory (IM4)
Org: Penny Haxell (University of Waterloo)
Extremal graph theory can be described as the study of how global properties of a graph can guarantee the existence of local substructures. A classical example is the theorem of Turán, which tells us the maximum number of edges that a graph with $n$ vertices can have, if it does not contain a complete subgraph with $r$ vertices. Many natural questions can be formulated as extremal graph problems, and the subject has developed into a rich theory. Applications abound in many fields, including number theory, optimization, theoretical computer science, economics, hardware design, and optical networks.
 
Thursday June 2
10:10 - 10:35 M. DeVos (Simon Fraser University), Edge Expansion, Cornett A121
10:40 - 11:05 A. Kostochka (University of Illinois at Urbana-Champaign), Packing hypergraphs with few edges, Cornett A121
11:10 - 11:35 D. Mubayi (University of Illinois at Chicago), Lower bounds for the independence number of hypergraphs, Cornett A121
11:40 - 12:05 O. Pikhurko (Carnegie Mellon University), Turan function of even cycles, Cornett A121
12:10 - 12:35 J. Verstraete (University of California at San Diego), Recent progress on bipartite Turan numbers, Cornett A121
 
Finite Fields in Combinatorics I (CM2)
Org: Daniel Panario (Carleton University)
In this minisymposium, several topics of combinatorics where finite fields play an important role are presented. The talks show the use of finite fields to construct combinatorial objects and to prove interesting results in areas such as designs, graphs, latin squares, codes and sequences, finite geometries, among others.
 
Tuesday May 31
10:10 - 10:35 Daniel Panario (Carleton University), Combinatorial Applications of Finite Fields, MacLaurin D110
10:40 - 11:05 Shonda Gosselin (University of Winnipeg), Paley uniform hypergraphs, MacLaurin D110
11:10 - 11:35 David Thomson (Carleton University), Sets of mutually orthogonal Latin hypercubes, MacLaurin D110
11:40 - 12:05 Petr Lisonek (Simon Fraser University), On the equivalence of quantum codes, MacLaurin D110
12:10 - 12:35 Tim Alderson (University of New Brunswick (Saint John)), Constructions of multiple wavelength codes ideal auto-correlation, MacLaurin D110
 
Finite Fields in Combinatorics II (CM8)
Org: Daniel Panario (Carleton University)
In this minisymposium, several topics of combinatorics where finite fields play an important role are presented. The talks show the use of finite fields to construct combinatorial objects and to prove interesting results in areas such as designs, graphs, latin squares, codes and sequences, finite geometries, among others.
 
Wednesday June 1
10:10 - 10:35 Aiden Bruen (University of Calgary), Information sets and linear algebra, MacLaurin D110
10:40 - 11:05 Kai-Uwe Schmidt (Simon Fraser University), Sets of symmetric matrices over finite fields, MacLaurin D110
11:10 - 11:35 Qiang Wang (Carleton University), Ambiguity and Deficiency of Permutations, MacLaurin D110
11:40 - 12:05 Brett Stevens (Carleton University), finite field constructions of an imperfect design, MacLaurin D110
12:10 - 12:35 Sudhir Ghorpade (Indian Institute of Technology), Coprime polynomial pairs, Hankel matrices, and splitting subspaces, MacLaurin D110
 
Generalized Hadamard Matrices and Applications (CM21)
Org: Aidan Roy and Ada Chan (University of Waterloo and York University)
A {\em generalized Hadamard matrix} is a complex $n \times n$ matrix $H$ such that all entries of $H$ have the same absolute value, and $HH^* = nI$. Like real Hadamard matrices, generalized Hadamards often have interesting combinatorial properties and constructions. However, they also have a number of important applications. In quantum information theory, certain generalized Hadamards correspond to optimal tomographic measurements. In the theory of Type II matrices, they are closely connected to association schemes.

In this minisymposium, we bring together people from various backgrounds to discuss the latest results and encourage communication between quantum information theorists and combinatorialists.

 
Thursday June 2
15:15 - 15:40 Robert Craigen (University of Manitoba), Some Circulant Generalized Weighing matrices, MacLaurin D101
15:45 - 16:10 Aidan Roy (University of Waterloo), Generalized Hadamard matrices and quantum measurements, MacLaurin D101
16:15 - 16:40 Alyssa Sankey (University of New Brunswick), Type-II matrices associated with 2-graphs and weighted strongly regular graphs, MacLaurin D101
16:45 - 17:10 Hadi Kharaghani (University of Lethbridge), Mutually unbiased complex weighing matrices, MacLaurin D101
 
Geometric Representations of Graphs I (CM6)
Org: Stefan Felsner (Technische Universitaet Berlin)
Visualizations and representations of graphs by means of intersections or contacts of geometric objects have been widely investigated. Classical examples are interval graphs and Koebe circle representations. When representations are given they can sometimes be exploited in optimization problems. In many instances these problems are hard for general graphs but become polynomial-time solvable when restricted to intersection or contact graphs with a given representations. Another class of problems is to compute the representation or to decide whether it exists. In this minisymposium we highlight some recent developments in this active area at the intersection of graph theory and discrete geometry.
 
Tuesday May 31
15:15 - 15:40 Matthew Francis (University of Toronto), On Segment graphs, Cornett A229
15:45 - 16:10 Jan Kratochvil (Charles University, Prague), Intersection graphs of homothetic polygons, Cornett A229
16:15 - 16:40 Tobias Müller (CWI, Amsterdam), The smallest grid needed to represent a geometric intersection graph, Cornett A229
16:45 - 17:10 Torsten Ueckerdt (Technische Universitaet Berlin), Edge-Intersection Graphs of Grid Paths - the Bend Number, Cornett A229
17:15 - 17:40 Sue Whitesides (University of Victoria, BC), On Upward Topological Book Embeddings of Upward Planar Digraphs, Cornett A229
 
Geometric Representations of Graphs II (CM9)
Org: Jan Kratochvil (Charles University, Prague, Czech republic)
Visualizations and representations of graphs by means of intersections or contacts of geometric objects have been widely investigated. Classical examples are interval graphs and Koebe circle representations. When representations are given they can sometimes be exploited in optimization problems. In many instances these problems are hard for general graphs but become polynomial-time solvable when restricted to intersection or contact graphs with a given representations. Another class of problems is to compute the representation or to decide whether it exists. In this minisymposium we highlight some recent developments in this active area at the intersection of graph theory and discrete geometry.
 
Wednesday June 1
10:10 - 10:35 George Mertzios (University of Haifa, Israel), Geometric intersection models on the plane and the 3D-space, Cornett A120
10:40 - 11:05 Marcus Schaefer (DePaul University, Chicago, U.S.A.), Removing Monotone Crossings, Cornett A120
11:10 - 11:35 Daniel Gonçalves (LIRMM, Montpellier, France), Planar Graphs as Contact or Intersection Graphs of Homothetic Triangles, Cornett A120
11:40 - 12:05 Stefan Felsner (Technische Universitaet, Berlin, Germany), Graphs and Rectangle Dissections, Cornett A120
12:10 - 12:35 Anna Lubiw (University of Waterloo), Simultaneous Graph Representations, Cornett A120
 
Graph Algorithms and Complexity (CT16)
 
Friday June 3
15:15 - 15:40 Steven Chaplick (University of Toronto), The Vertex Leafage of Chordal Graphs, MacLaurin D103
15:45 - 16:10 William Sean Kennedy (McGill), Finding a smallest odd hole in a claw-free graph using global structure, MacLaurin D103
16:15 - 16:40 Joseph Manning (University College Cork), Linear-Time Canonical Encoding of Plane Graphs, MacLaurin D103
16:45 - 17:10 R. Sritharan (The University of Dayton), Largest induced matching: computation and min-max relations, MacLaurin D103
 
Graph Games (CT9)
 
Wednesday June 1
15:15 - 15:40 Stephen Finbow (St Francis Xavier), Efficiency of Watchmen's Walks, MacLaurin D114
15:45 - 16:10 Shannon Fitzpatrick (University of Prince Edward Island), Copwin Edge Critical Graphs, MacLaurin D114
16:15 - 16:40 Dan Hefetz (Queen Mary University of London), Fast embedding of spanning trees in biased Maker-Breaker games, MacLaurin D114
16:45 - 17:10 Abbas Mehrabian (University of Waterloo), On a Generalization of Meyniel's Conjecture on the Cops and Robbers Game, MacLaurin D114
17:15 - 17:40 Suzanne Seager (Mount Saint Vincent University), Locating a Robber on a Graph, MacLaurin D114
 
Graph Searching (CM3)
Org: Anthony Bonato (Ryerson University), Nancy Clarke (Acadia University) and Boting Yang (University of Regina)
In graph searching a set of searchers pursue intruders in a two-player game played on a graph. The rules of the game may vary according to the capabilities of the players such as relative speed, sensor capabilities, or visibility. There has been much recent interest in graph searching, resulting in a wealth of structural, algorithmic, and probabilistic results. The main aim of the minisymposium (co-organized with Nancy Clarke and Boting Yang) is to bring together leading researchers in the field. The proposed speakers will cover such topics as Cops and Robbers and its variants, sweeping, graph cleaning, and firefighting.
 
Tuesday May 31
10:10 - 10:35 Nancy Clarke (Acadia), Characterizations of $k$-copwin graphs, Cornett A229
10:40 - 11:05 Danny Dyer (Memorial), Fast searching graphs with few searchers, Cornett A229
11:10 - 11:35 Geňa Hahn (Montréal), Cops-and-robbers revisited, Cornett A229
11:40 - 12:05 Gary MacGillivray (Victoria), A characterization of infinite cop-win graphs, Cornett A229
12:10 - 12:35 Richard Nowakowski (Dalhousie), Cops and Robber with different edges sets, Cornett A229
 
Graph Theory I (CT6)
 
Wednesday June 1
10:10 - 10:35 Richard Brewster (Thompson Rivers University), Lexicographic products with high reconstruction number, MacLaurin D103
10:40 - 11:05 Dennis D.A. Epple (University of Victoria), Covering lexicographic products of graphs with independent sets and cliques, MacLaurin D103
11:10 - 11:35 Terry McKee (Wright State University), Graphs that have clique (partial) 2-trees, MacLaurin D103
11:40 - 12:05 Bode Michel (Otto-von-Guericke-Universität Magdeburg), Good edge labelings of graphs of average degree at most 3, MacLaurin D103
12:10 - 12:35 K. B. Reid (California State University San Marcos), Landau's Theorem Revisited Again, MacLaurin D103
 
Graph Theory II (CT15)
 
Friday June 3
10:10 - 10:35 Russell Campbell (University of Victoria), Reflexive Injective Oriented Colouring, MacLaurin D103
10:40 - 11:05 Andrzej Czygrinow (Arizona State University), Tiling in Bipartite Graphs, MacLaurin D103
11:10 - 11:35 Andrew D. King (Columbia University), Proving the Lovász-Plummer Conjecture, MacLaurin D103
11:40 - 12:05 Asiyeh Sanaei (Memorial University of Newfoundland), Constructions of 3-existentially closed graphs using graph operations, MacLaurin D103
12:10 - 12:35 Henry Martyn Mulder (Econometric Institute, Erasmus Universiteit, Rotterdam), Axiomatic characterization of location functions, MacLaurin D103
 
Graph Theory: Colouring (CT2)
 
Tuesday May 31
10:10 - 10:35 Kailyn Young (University of Victoria), 2-dipath k-colourings, MacLaurin D103
10:40 - 11:05 Mark Kayll (University of Montana), Uniquely $D$-colourable digraphs with large girth, MacLaurin D103
11:10 - 11:35 Bernard Lidicky (Charles University), List coloring and crossings, MacLaurin D103
11:40 - 12:05 Ararat Harutyunyan (Simon Fraser University), Gallai's Theorem for List Coloring of Digraphs, MacLaurin D103
 
Graph Theory: Cycles (CT17)
 
Friday June 3
15:15 - 15:40 Alewyn Burger (Stellenbosch University), An infinite family of Planar Hypohamiltonian Oriented Graphs, MacLaurin D110
15:45 - 16:10 Daryl Funk (Simon Fraser University), On the hamiltonicity of line graphs of locally finite, 6-edge-connected graphs, MacLaurin D110
16:15 - 16:40 Bert Hartnell (Saint Mary's University), Decycling in the Cartesian Product, MacLaurin D110
16:45 - 17:10 Tomas Kaiser (University of West Bohemia, Pilsen, Czech Republic), Covering a graph by forests and a matching, MacLaurin D110
17:15 - 17:40 Khaled Salem (The British University in Egypt), A characterization of 1-cycle resonant graphs among bipartite 2-connected plane graphs, MacLaurin D110
 
Graphs and Combinatorial Geometry (CT7)
 
Wednesday June 1
10:10 - 10:35 David Herscovici (Quinnipiac University), Optimal Pebbling in Hypercubes using Error-correcting codes, MacLaurin D101
10:40 - 11:05 Tony Nixon (Lancaster University), Combinatorial Rigidity on Surfaces, MacLaurin D101
11:10 - 11:35 David Richter (Western Michigan University), How to draw a 4-edge-colored graph, MacLaurin D101
11:40 - 12:05 Jacobus Swarts (Vancouver Island University), The $C_k$-extended Graft Construction, MacLaurin D101
 
Hypergraph Decompositions (CM23)
Org: Shonda Gosselin (University of Winnipeg)
This minisymposium showcases recent results involving hypergraph decompositions and their relation to combinatorial designs. We define and construct cyclic decompositions of complete uniform hypergraphs and complete multipartite hypergraphs, and examine their connection to both self-complementary graphs and large sets of designs. We also investigate covering and packing versions of Peter Cameron's generalized $t$-designs, which correspond to special coverings and packings of hypergraphs.
 
Friday June 3
10:10 - 10:35 A. Pawel Wojda (AGH University of Science and Technology, Krakow, Poland.), Cyclic partitions of complete hypergraphs, MacLaurin D110
10:40 - 11:05 Mateja Sajna (University of Ottawa), Regular self-complementary uniform hypergraphs, MacLaurin D110
11:10 - 11:35 Shonda Gosselin (University of Winnipeg), Regular or vertex-transitive q-complementary hypergraphs, MacLaurin D110
11:40 - 12:05 Robert Bailey (University of Regina), Generalized covering designs as hypergraph covers, MacLaurin D110
12:10 - 12:35 Andrea Burgess (Ryerson University), Generalized packing designs and hypergraph packings, MacLaurin D110
 
Matrices and Sequences (CT10)
 
Thursday June 2
10:10 - 10:35 Richard Anstee (UBC), Forbidden Configurations: Progress towards a Conjecture, MacLaurin D101
10:40 - 11:05 Daniel Katz (Simon Fraser University), Cross-Correlations of $p$-ary Maximal-Length Sequences: the Few and the Rational, MacLaurin D101
11:10 - 11:35 Shahla Nasserasr (University of Regina), Totally Positive Shapes and TP$_k$-completable Patterns, MacLaurin D101
11:40 - 12:05 Murray Patterson (University of British Columbia), The Gapped Consecutive-Ones Property, MacLaurin D101
12:10 - 12:35 Miguel Raggi (UBC), Genetic Algorithms in Forbidden Configurations, MacLaurin D101
 
Optimal Design of Experiments (CM14)
Org: Julie Zhou (University of Victoria)
The goal of this session is to bring together leading researchers in the areas of optimal design of experiments to exchange and discuss research ideas, and to encourage interactions between researchers in statistics and researchers in discrete mathematics. Research results in combinatorics and numerical algorithms are very useful to construct optimal designs. Five leading researchers in optimal design of experiments have tentatively agreed to give talks in this proposed session.
 
Wednesday June 1
15:15 - 15:40 Ching-Shui Cheng (University of California, Berkeley), Optimal Block Designs and Graphs, MacLaurin D101
15:45 - 16:10 John Stufken (University of Goergia), Some combinatorial structures useful in design of experiments, MacLaurin D101
16:15 - 16:40 Boxin Tang (Simon Fraser University), Optimal Fractions of Two-level Factorials under a Baseline Parametrization, MacLaurin D101
16:45 - 17:10 Weng Kee Wong (University of California, Los Angeles), Algorithms for Generating Minimax Optimal Experimental Designs, MacLaurin D101
17:15 - 17:40 Jane Ye (University of Victoria), Minimizing the condition number to construct design points for polynomial regression models, MacLaurin D101
 
Probabilistic Combinatorics (IM5)
Org: Tom Bohman and Po-Shen Loh (Carnegie Mellon University)
Probabilistic Combinatorics stands at the intersection of several thriving areas of Mathematics and Computer Science. It focuses on the combinatorial properties of random discrete objects (e.g., random graphs), and their potential applications to other branches of Mathematics. This mini-symposium will highlight a variety of recent advances in the field. We also intend to use this forum to make state of the art probabilistic techniques available to a broader audience.
 
Thursday June 2
15:15 - 15:40 Louigi Addario-Berry (McGill University), The second eigenvalue of random lifts, Cornett A121
15:45 - 16:10 Kevin Costello (Georgia Institute of Technology), On Randomizing Derandomized Greedy Algorithms, Cornett A121
16:15 - 16:40 Po-Shen Loh (Carnegie Mellon University), Rainbow Hamilton cycles in random graphs, Cornett A121
16:45 - 17:10 Bruce Reed (McGill University), Bounding $\chi$ as a convex combination of $\omega$ and $\Delta +1$, Cornett A121
17:15 - 17:40 Jacob Fox (MIT), Graph regularity and removal lemmas, Cornett A121
 
Random Structures (CT11)
 
Thursday June 2
10:10 - 10:35 Ross J. Kang (Durham University), Subset Glauber dynamics mixes rapidly on graphs of bounded tree-width., MacLaurin D103
10:40 - 11:05 Mitchel T. Keller (London School of Economics and Political Science), Linear Extension Diameter and Reversal Ratio, MacLaurin D103
11:10 - 11:35 Stephen J. Young (University of California, San Diego), Braess's Paradox in Sparse Random Graphs, MacLaurin D103
 
Spectral Graph Theory (CM17)
Org: Bojan Mohar and Steve Kirkland (Simon Fraser University)
Spectral graph theory is an important part of discrete mathematics with applications in many areas such as computer science, chemistry, network design and coding theory. One of the main goals of the theory is to deduce the principal properties of a graph from the spectral information furnished by one or more of the matrices associated with it. This minisymposium will showcase some of such connections and their applications.
 
Thursday June 2
10:10 - 10:35 Bojan Mohar (Simon Fraser University), Spectrally degenerate graphs, Cornett A120
10:40 - 11:05 Sebastian Cioaba (University of California, San Diego), Eigenvalues and the structure of graphs., Cornett A120
11:10 - 11:35 Vlado Nikiforov (University of Memphis), The Ky Fan norms of graphs and matrices, Cornett A120
11:40 - 12:05 Steve Butler (University of California, Los Angeles), Forming graphs which are cospectral for the normalized Laplacian, Cornett A120
12:10 - 12:35 Azhvan Sheikh Ahmady (Simon Fraser University), Eigenvalues of graphs with many vertices of large degree, Cornett A120
 
Structured Graphs and Algorithms (CM10)
Org: Jing Huang and Gary MacGillivray (University of Victoria)
Combinatorial problems that are hard for general graphs are sometimes efficiently solvable for graphs belonging to classes like chordal, bi-arc, interval graphs, local tournaments, and the like. In some instances, for example the list homomorphism problem, it is precisely membership in such a class that distinguishes the polynomial and NP-complete instances of the problem. The speakers in this minisymposium will present results on the structure of graphs belonging to various special classes, and the complexity of combinatorial problems on such graphs.
 
Wednesday June 1
10:10 - 10:35 Jorgen Bang-Jensen (University of Southern Denmark), Finding an induced subdivision of a digraph, Cornett A121
10:40 - 11:05 Ragnar Nevries (University of Rostock), Recognizing polar and monopolar graphs, Cornett A121
11:10 - 11:35 Ross Churchley (University of Victoria), Partitioning graphs via edge-coloured homomorphisms, Cornett A121
11:40 - 12:05 Mathew Francis (Charles University), Intersection dimensions of graphs, Cornett A121
12:10 - 12:35 Jing Huang (University of Victoria), Chronological interval digraphs, Cornett A121

Event Sponsors

Centre de recherches mathématiques Fields Institute MITACS Pacific Institute for the Mathematical Sciences Canadian Mathematical Society University of Victoria