Competitive Decision Algorithm for the Rooted Delay-constrained Minimum Spanning Tree

Abstract-In this paper, we investigate a rooted delayconstrained minimum spanning tree (RDCMST) problem. RDCMST seeks to find a minimum spanning tree in which no path from a specified root node to any other nodes may exceed a given delay bound. RDCMST is a NP-hard combinatorial optimization problem arising both in scientific research and practical engineering. Competitive decision algorithm (CDA) is a newly proposed meta-heuristic algorithm for solving complex combinatorial optimization problems. A new CDA algorithm for RDCMST problem is proposed in this paper. Restricted candidate list (RCL) and randomly choosing resource are introduced in CDA for the first time. We reduce the search space based on the mathematical properties of RDCMST. To evaluate the algorithm, numerical computational experiments are performed

Particle swarm optimization for the Steiner tree in graph and delay-constrained multicast routing problems

This paper presents the first investigation on applying a particle swarm optimization (PSO) algorithm to both the Steiner tree problem and the delay constrained multicast routing problem. Steiner tree problems, being the underlining models of many applications, have received significant research attention within the meta-heuristics community. The literature on the application of meta-heuristics to multicast routing problems is less extensive but includes several promising approaches. Many interesting research issues still remain to be investigated, for example, the inclusion of different constraints, such as delay bounds, when finding multicast trees with minimum cost. In this paper, we develop a novel PSO algorithm based on the jumping PSO (JPSO) algorithm recently developed by Moreno-Perez et al. (Proc. of the 7th Metaheuristics International Conference, 2007), and also propose two novel local search heuristics within our JPSO framework. A path replacement operator has been used in particle moves to improve the positions of the particle with regard to the structure of the tree. We test the performance of our JPSO algorithm, and the effect of the integrated local search heuristics by an extensive set of experiments on multicast routing benchmark problems and Steiner tree problems from the OR library. The experimental results show the superior performance of the proposed JPSO algorithm over a number of other state-of-the-art approaches