Colloquium Announcement
Department of Mathematics
West Virginia University
for
Thursday, February 12, 1998, at 3:45pm
in 324 Armstrong Hall
(Tea and cookies begin at 3:00 in coffee room.)
Professor Arthur M. Hobbs
Texas A & M Univ
Applications of Tree Packings and Coverings
The talk will be suitable for a general audience.
Students are strongly encouraged to participate.
Abstract
Given an integer k, a graph G is packed with k trees if
it has k edge-disjoint subgraphs, each of which is a spanning tree of
G. Also, graph G is covered with k trees if there are k
subgraphs of G such that each is a tree and the union of the k
subgraphs is G.
At first glance, these two technical definitions would not seem to be
likely to lead to anything interesting. But it turns out that packings
and coverings by trees have many applications. In this talk, four
of the applications will be discussed: spanning Eulerian subgraphs
and their connection to the Hamiltonian cycle problem, the construction
of rigid planar frameworks, the analysis of electrical networks, and
the protection of communication networks from nuclear attack.
The information on the future (and past) Colloquia can be also found on web at the
address:
http://www.math.wvu.edu/homepages/kcies/colloquium.html