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31.
L.G. Casado I. García T. Csendes V.G. Ruíz 《Journal of Optimization Theory and Applications》2003,118(1):27-43
Based on the investigation carried out in Ref. 1, this paper incorporates new studies about the properties of inclusion functions on subintervals while a branch-and-bound algorithm is solving global optimization problems. It is found that the relative place of the global minimum value within the inclusion function value of the objective function at the current interval indicates mostly whether the given interval is close to a minimizer point. This information is used in a heuristic interval rejection rule that can save a considerable amount of computation. Illustrative examples are discussed and an extended numerical study shows the advantages of the new approach. 相似文献
32.
33.
Linear mixed 0–1 integer programming problems may be reformulated as equivalent continuous bilevel linear programming (BLP)
problems. We exploit these equivalences to transpose the concept of mixed 0–1 Gomory cuts to BLP. The first phase of our new
algorithm generates Gomory-like cuts. The second phase consists of a branch-and-bound procedure to ensure finite termination
with a global optimal solution. Different features of the algorithm, in particular, the cut selection and branching criteria
are studied in details. We propose also a set of algorithmic tests and procedures to improve the method. Finally, we illustrate
the performance through numerical experiments. Our algorithm outperforms pure branch-and-bound when tested on a series of
randomly generated problems.
Work of the authors was partially supported by FCAR, MITACS and NSERC grants. 相似文献
34.
Some authors claim that reporting the best result obtained by a stochastic algorithm in a number of runs is more meaningful
than reporting some central statistic. In this short note, we analyze and refute the main argument brought in favor of this
statement. 相似文献
35.
In this paper, we provide bounds for the expected value of the log of the condition number C(A) of a linear feasibility problem given by a n × m matrix A (Ref. 1). We show that this expected value is O(min{n, m log n}) if n > m and is O(log n) otherwise. A similar bound applies for the log of the condition number C
R(A) introduced by Renegar (Ref. 2). 相似文献
36.
设计IIR数字滤波器的遗传优化算法 总被引:2,自引:0,他引:2
提出了IIR数字滤波器设计的遗传优化法。这是一种模拟自然遗传和达尔文进化理论的随机并行优化算法。首先,详细描述了遗传算法并给出了计算步骤,然后将遗传算法用于IIR数字滤波器的优化设计,最后给出了模拟计算结果。 相似文献
37.
Marco Marletta 《Advances in Computational Mathematics》1994,2(2):155-184
This paper discusses the numerical solution of eigenvalue problems for Hamiltonian systems of ordinary differential equations.
Two new codes are presented which incorporate the algorithms described here; to the best of the author’s knowledge, these
are the first codes capable of solving numerically such general eigenvalue problems. One of these implements a new new method
of solving a differential equation whose solution is a unitary matrix. Both codes are fully documented and are written inPfort-verifiedFortran 77, and will be available in netlib/aicm/sl11f and netlib/aicm/sl12f. 相似文献
38.
Manufacturing cell formation using similarity coefficients and a parallel genetic TSP algorithm: Formulation and comparison 总被引:2,自引:0,他引:2
J. BalakrishnanP. D. Jog 《Mathematical and Computer Modelling》1995,21(12):61-73
Many algorithms have been proposed to form manufacturing cells from component routings. However, many of these do not have the capability of solving large problems. We propose a procedure using similarity coefficients and a parallel genetic implementation of a TSP algorithm that is capable of solving large problems of up to 1000 parts and 1000 machines. In addition, we also compare our procedure with many existing procedures using nine well-known problems from the literature.
The results show that the proposed procedure compares well with the existing procedures and should be useful to practitioners and researchers. 相似文献
39.
Genetic algorithms are stochastic search algorithms that have been applied to optimization problems. In this paper we analyze the run-time complexity of a genetic algorithm when we are interested in one of a set of distinguished solutions. One such case occurs when multiple optima exist. We define the worst case scenario and derive a probabilistic worst case bound on the number of iterations required to find one of these multiple solutions of interest. 相似文献
40.
In apparel industry, manufacturers developed standard allowed minutes (SAMs) databases on various manufacturing operations in order to facilitate better scheduling, while effective production schedules ensure smoothness of downstream operations. As apparel manufacturing environment is fuzzy and dynamic, rigid production schedules based on SAMs become futile in the presence of any uncertainty. In this paper, a fuzzification scheme is proposed to fuzzify the static standard time so as to incorporate some uncertainties, in terms of both job-specific and human related factors, into the fabric-cutting scheduling problem. A genetic optimisation procedure is also proposed to search for fault-tolerant schedules using genetic algorithms, such that makespan and scheduling uncertainties are minimised. Two sets of real production data were collected to validate the proposed method. Experimental results indicate that the genetically optimised fault-tolerant schedules not only improve the operation performance but also minimise the scheduling risks. 相似文献