CECM Home > Events > CECM Annual Summer Meeting 2007 > Program > Talk Abstracts

#### Talk Abstracts

###### Spectra of (3,6)-polyhedra

*Luis Goddyn · Simon Fraser University*

Abstract:

A (3,6)-polyhedron is a 3-regular planar graph in which all faces are of size 3 or 6. These graphs are of interest to Chemists as they are related to Fullerenes. It was conjectured by Fowler et al. that the spectrum of the adjacency matrix (the "energy spectrum") of any (3,6)-polyhedron consists of pairs of opposite values λ, -λ, and four exceptional eigenvalues {3, -1, -1, -1}.

We prove this conjecture by expressing each (3,6)-polyhedron as a Cayley sum graph. I will elaborate a bit on the experimentation process which led to this result.

This is joint work with Matt DeVos, Robert Šámal, and Bojan Mohar.

###### What's new in Maple 11

*Allan Wittkopf · Maplesoft*

Abstract:

I will give a non-exhaustive high level description of many of the new features in Maple 11, including new/improved plots and plotting routines, new packages, and enhancements for many computational areas of Maple.

###### Applications of Queuing Theory in the Public Sector: The Health Care System and the Criminal Justice System

*Sandy Rutherford · IRMACS, Simon Fraser University*

Abstract:

The Complex Systems Modelling Group at IRMACS has been involved in a number of projects to model the delivery of public services by the Government of British Columbia. A review of the projects and the lessons learned will be given. Two projects will be discussed in detail. The first is modelling of the wait list for cataract surgery for the Ministry of Health. The second is a high level model of the criminal justice system, which is under development for the Ministry of the Attorney General and the Ministry of Public Safety and the Solicitor General.

###### SAGE — Open Source Mathematical Software

*William Stein · University of Washington*

Abstract:

The goal of the SAGE project is to create a viable free open source alternative to Mathematica, Magma, Matlab, and Maple. See http://www.sagemath.org/.

###### Theory of ROOF walks

*Richard Crandall · Apple Inc.*

Abstract:

Running-out-of-fuel (ROOF) walks are random walks whereby the successive jumps steadily decay in magnitude. For example, a ROOF walker might jump ±1 unit, then ±1/2, ±1/3, and so on, so that the walker can wander arbitrarily far even though its fuel store (total variance) is finite. The lecturer will connect these ROOF walks with some recent result in experimental mathematics, such results involving sinc-integrals of surprising value.