James MacGregor Smith

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An integrative overview of the algorithmic characteristics of three well-known polynomialtime heuristics for the undirected Steiner minimum tree problem:shortest path heuristic (SPH),distance network heuristic (DNH), andaverage distance heuristic (ADH) is given. The performance of thesesingle-pass heuristics (and some variants) is compared and contrasted(More)
An O(n log n) heuristic for the Euclidean Steiner Minimal Tree (ESMT) problem is presented. The algorithm is based on a decomposition approach which first partitions the vertex set into triangles via the Delaunay triangulation, then "recomposes" the suboptimal Steiner Minimal Tree (SMT) according to the Voronoi diagram and Minimum Spanning Tree (MST) of the(More)
| The \Steiner minimal tree" (SMT) of a point set P is the shortest network of \wires" which will suuce to \electrically" interconnect P. The \minimum spanning tree" (MST) is the shortest such network when only intersite line segments are permitted. The \Steiner ratio" (P) of a point set P is the length of its SMT divided by the length of its MST. It is of(More)
0377-2217/$ see front matter Published by Elsevier doi:10.1016/j.ejor.2008.08.025 * Corresponding author. Tel.: +1 413 546 2749. E-mail addresses: astepano@ecs.umass.edu (A. Ste edu (J.M. Smith). 1 Tel.: +1 413 545 4542. In this paper, the optimal design and analysis of evacuation routes in transportation networks is examined. An methodology for optimal(More)
Recent findings relating to SOX transcription factors indicate that defects in organogenesis can be caused not only by impairment of the biochemical properties of transcription factors but also, in some cases, by deficient nuclear import. In addition, experimentally interfering with the nuclear export signals of some SOX factors has now been found to cause(More)