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181.
COSEARCH: A Parallel Cooperative Metaheuristic 总被引:1,自引:0,他引:1
In order to design a well-balanced metaheuristic for robustness, we propose the COSEARCH approach which manages the cooperation
of complementary heuristic methods via an adaptive memory which contains a history of the search already done. In this paper,
we present the idiosyncrasies of the COSEARCH approach and its application for solving large scale instances of the quadratic
assignment problem (QAP). We propose an original design of the adaptive memory in order to focus on high quality regions of
the search and avoid attractive but deceptive areas. For the QAP, we have hybridized three heuristic agents of complementary
behaviours: a Tabu Search is used as the main search algorithm, a Genetic Algorithm is in charge of the diversification and
a Kick Operator is applied to intensify the search. The evaluations have been executed on large scale network of workstations
via a parallel environment which supports fault tolerance and adaptive dynamic scheduling of tasks. 相似文献
182.
There is a general interest in ranking schemes applied to complex entities described by multiple attributes. Published rankings
for universities are in great demand but are also highly controversial. We compare two classification and ranking schemes
involving universities; one from a published report, ‘Top American Research Universities’ by the University of Florida's TheCenter and the other using DEA. Both approaches use the same data and model. We compare the two methods and discover important equivalences.
We conclude that the critical aspect in classification and ranking is the model. This suggests that DEA is a suitable tool
for these types of studies. 相似文献
183.
The aim of this article is to discuss an asymptotic approximation model and its convergence for the minimax semi-infinite programming problem. An asymptotic surrogate constraints method for the minimax semi-infinite programming problem is presented by making use of two general discrete approximation methods. Simultaneously, the consistence and the epi-convergence of the asymptotic approximation problem are discussed. 相似文献
184.
In this paper, we propose the treatment of complex reservoir operation problems via our newly developed tool of fuzzy criterion
decision processes. This novel approach has been shown to be a more flexible and useful analysis tool especially when it is
desirable to incorporate an expert’s knowledge into the decision models. Additionally, it has been demonstrated that this
form of decision models will usually result in an optimal solution, which guarantees the highest satisfactory degree. We provide
a practical exemplification procedure for the models presented as well as an application example. 相似文献
185.
Converging Marriage in Honey-Bees Optimization and Application to Stochastic Dynamic Programming 总被引:1,自引:0,他引:1
Hyeong Soo Chang 《Journal of Global Optimization》2006,35(3):423-441
In this paper, we first refine a recently proposed metaheuristic called “Marriage in Honey-Bees Optimization” (MBO) for solving
combinatorial optimization problems with some modifications to formally show that MBO converges to the global optimum value.
We then adapt MBO into an algorithm called “Honey-Bees Policy Iteration” (HBPI) for solving infinite horizon-discounted cost
stochastic dynamic programming problems and show that HBPI also converges to the optimal value. 相似文献
186.
We examine a sequential selection problem in which a single option must be selected. Each option's value is a function of its attributes, whose precise values can be ascertained at a given cost. We prove the optimality of a threshold stopping rule for a general class of objective functions. 相似文献
187.
We present a new approach, requiring the solution of a SemiDefinite Program, for decomposing the Hessian of a nonseparable mixed-integer quadratic problem to permit using perspective cuts to improve its continuous relaxation bound. The new method favorably compares with a previously proposed one requiring a minimum eigenvalue computation. 相似文献
188.
Matthew D. Bailey Steven M. Shechter Andrew J. Schaefer 《Operations Research Letters》2006,34(3):307-315
We consider a general adversarial stochastic optimization model. Our model involves the design of a system that an adversary may subsequently attempt to destroy or degrade. We introduce SPAR, which utilizes mixed-integer programming for the design decision and a Markov decision process (MDP) for the modeling of our adversarial phase. 相似文献
189.
本文研究DNA的两两序列比时,提出了基于快速沃尔什变换的新方法。经过计算模拟分析可知,比对的时间复杂度和空间复杂度明显降低. 相似文献
190.
符号几何规划的一种分解方法 总被引:1,自引:0,他引:1
针对符号几何规划提出了一种直接的分解方法,将难于求解的符号几何规划问题等价地转化为一个非线性程度很低的可分离规划,为寻求困难度高且规模较大的符号几何规划问题的求解提供了一种方法,特别是经此方法分解后的每个子问题均易于求解,最后给出了数值实例,验证了此方法的有效性. 相似文献