Aura II: Combining Negative Thinking and Branch-and-Bound in Unate Covering Problems
نویسندگان
چکیده
Recently a novel technique has been published to augment traditional Branchand-Bound (B&B) while solving exactly a discrete optimization problem [Goldberg et al., 1997]. This technique is based on the negative thinking paradigm and has been applied to develop , a Unate Covering Problem (UCP) solver which reportedly was able to deal efficiently with some time-consuming benchmark problems. However, on average was not able to compete with , a classical UCP solver based on several new bounding techniques proposed by O. Coudert in his breakthrough paper [Coudert, 1996]. This fact left open the question on the practical impact of the negative thinking paradigm. The present work is meant to settle this question. The paper discusses the details of , a new implementation of the negative thinking paradigm for UCP which combines the best of and . Experimental results show the
منابع مشابه
Negative thinking in branch-and-bound: the case of unate covering
We introduce a new technique for solving some discrete optimization problems exactly. The motivation is that when searching the space of solutions by a standard branch-and-bound (B&B) technique, often a good solution is reached quickly and then improved only a few times before the optimum is found: hence, most of the solution space is explored to certify optimality, with no improvement in the c...
متن کاملCofactoring-Based Upper Bound Computation for Covering Problems
This paper introduces an efficient technique to compute a tight upper bound for the unate and binate covering problems. It is known that a covering problem can be solved by finding a shortest path on a BDD representing a satisfiability formula. Our technique is based on finding an approximation to the shortest path by identifying a path on a BDD composed of as many negative edges as possible. T...
متن کاملSearch pruning techniques in SAT-based branch-and-bound algorithmsfor the binate covering problem
Covering problems are widely used as a modeling tool in electronic design automation. Recent years have seen dramatic improvements in algorithms for the unate/binate covering problem (UCP/BCP). Despite these improvements, BCP is a well-known computationally hard problem with many existing real-world instances that currently are hard or even impossible to solve. In this paper we apply search pru...
متن کاملOn Solving Binate Covering Problems
Binate (or unate) covering problems occur at several steps during logic synthesis including two-level minimization and DAG covering. This paper presents a better lower bound computation algorithm and two new pruning techniques that significantly improve the efficiency of binate covering problem solvers. We show that these techniques reduce by up to three orders of magnitude the time required to...
متن کاملA New Heuristic Solution Method for Maximal Covering Location-Allocation Problem with M/M/1 Queueing System
We consider the queueing maximal covering location-allocation problem (QM-CLAP) with an M/M/1 queueing system. We propose a new solution procedure based on decomposition of the problem into smaller sub-problems. We solve the resulting sub-problems both with a branch and bound algorithm and with the meta-heuristic GRASP. We also solve the entire model with GRASP. Computational results for these ...
متن کامل