Gr\"unbaum Colorings of Toroidal Triangulations (2008)
Albertson, Michael O., Alpert, Hannah, Belcastro, Sarah-marie, Haas, Ruth
We prove that if G is a triangulation of the torus and \chi(G) \neq 5, then there is a 3-coloring of the edges of G so that the edges bounding every face are assigned three different colors.
Characterizations of arboricity of graphs (2008)
The aim of this paper is to give several characterizations for the following two classes of graphs: (i) graphs for which adding any l edges produces a graph which is decomposible into k spanning...
Abstract Partial List Colorings (2008)
Michael O. Albertson, Sara Grossman, Ruth Haas
Suppose G is an s-choosable graph with n vertices, and every vertex of G is assigned a list of t colors. We conjecture that at least t s · n of the vertices of G can be colored from these lists. We...
Michael O. Albertson, Sara Grossman, Ruth Haas
Suppose G is an s-choosable graph with n vertices, and every vertex of G is assigned a list of t colors. We conjecture that at least t
Characterizing Sparse Graphs by Map Decompositions (2007)
Haas, Ruth, Lee, Audrey, Streinu, Ileana, Theran, Louis
A {\bf map} is a graph that admits an orientation of its edges so that each vertex has out-degree exactly 1. We characterize graphs which admit a decomposition into $k$ edge-disjoint maps after: (1)...
Properties of Twisted Involutions in Signed Permutation Notation (2006)
Ruth Haas, Aloysius G. Helminck, Nicole Rizki
In algebraic contexts Weyl group elements are usually represented in terms of generators and relations, where representation is not unique. For computational purposes, a more combinatorial...
Implementing an algorithm for the twisted involution poset for (2006)
Kathryn Brenneman, Ruth Haas, Aloysius G. Helminck
Weyl groups
Planar Minimally Rigid Graphs and Pseudo-Triangulations (2004)
Ruth Haas, David Orden, Günter Rote, Francisco Santos, Brigitte Servatius, Herman Servatius, ...
Pointed pseudo-triangulations are planar minimally rigid graphs embedded in the plane with pointed vertices (adjacent to an angle larger than π). In this paper we prove that the opposite...
Planar Minimally Rigid Graphs and Pseudo-Triangulations (2003)
Haas, Ruth, Orden, David, Rote, Guenter, Santos, Francisco, Servatius, Brigitte, Servatius, Herman, ...
Pointed pseudo-triangulations are planar minimally rigid graphs embedded in the plane with pointed vertices (adjacent to an angle larger than 180 degrees. In this paper we prove that the opposite...
Planar Minimally Rigid Graphs and Pseudo-Triangulations (2003)
Ruth Haas, David Orden, Günter Rote, Francisco Santos, Brigitte Servatius, Hermann Servatius, ...
Pointed pseudo-triangulations are planar minimally rigid graphs embedded in the plane with pointed vertices (incident to an angle larger than #). In this paper we prove that the opposite statement is...
Bounds on the signed domination number of a graph. (2001)
Let G = (V, E) be a simple graph on vertex set V and define a function f: V →{−1, 1}. The function f is a signed dominating function if for every vertex x ∈ V, the closed neighborhood of x...
Berlin, Humboldt-U., Med. F., Diss. v. 12. Juli 1957 (Nicht f. d. Aust.).