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941.
942.
周奇年 《原子与分子物理学报》1997,14(2):260-263
阐述了计算机科学对原子分子学科研究的重要作用,针对原子与分子领域中一些典型的问题,介绍了计算方法及程序设计,并对有关课题编出了计算程序。从而表明:借助于计算机可使原子与分子研究工作规范化、工程化,计算机及其程序设计是原子分子工程的设计基础 相似文献
943.
Paul Armand 《Computational Optimization and Applications》2003,26(1):5-34
We describe an infeasible interior point algorithm for convex minimization problems. The method uses quasi-Newton techniques for approximating the second derivatives and providing superlinear convergence. We propose a new feasibility control of the iterates by introducing shift variables and by penalizing them in the barrier problem. We prove global convergence under standard conditions on the problem data, without any assumption on the behavior of the algorithm. 相似文献
944.
区域水资源承载力模糊线性规划模型及应用 总被引:1,自引:0,他引:1
凌和良 《数学的实践与认识》2008,38(24)
首先按照联合国教科文组织提出的资源承载力定义,给出水资源承载力的定义,建立了水资源承载力的模糊线性规划模型,然后运用这模型对江西省的近期水资源承载力问题进行研究,数据结果表明模型的应用是成功的. 相似文献
945.
在证券的价格过程是几何布朗运动的前提下,建立了最优投资组合的多目标规划模型,使得投资收益最大和投资风险最小,并利用线性加权和法求得有效解.最后用实例进行分析. 相似文献
946.
Marcus Ritt Alysson M. Costa Sergio Mergen Viviane M. Orengo 《European Journal of Operational Research》2009
We introduce a problem called maximum common characters in blocks (MCCB), which arises in applications of approximate string comparison, particularly in the unification of possibly erroneous textual data coming from different sources. We show that this problem is NP-complete, but can nevertheless be solved satisfactorily using integer linear programming for instances of practical interest. Two integer linear formulations are proposed and compared in terms of their linear relaxations. We also compare the results of the approximate matching with other known measures such as the Levenshtein (edit) distance. 相似文献
947.
探讨了n维复形上一类具有混合约束的多目标规划问题,并运用代数拓扑方法得出这类规划问题的有效解。 相似文献
948.
Cover inequalities are commonly used cutting planes for the 0–1 knapsack problem. This paper describes a linear-time algorithm (assuming the knapsack is sorted) to simultaneously lift a set of variables into a cover inequality. Conditions for this process to result in valid and facet-defining inequalities are presented. In many instances, the resulting simultaneously lifted cover inequality cannot be obtained by sequentially lifting over any cover inequality. Some computational results demonstrate that simultaneously lifted cover inequalities are plentiful, easy to find and can be computationally beneficial. 相似文献
949.
A finite branch-and-bound algorithm for nonconvex quadratic programming via semidefinite relaxations
Existing global optimization techniques for nonconvex quadratic programming (QP) branch by recursively partitioning the convex
feasible set and thus generate an infinite number of branch-and-bound nodes. An open question of theoretical interest is how
to develop a finite branch-and-bound algorithm for nonconvex QP. One idea, which guarantees a finite number of branching decisions,
is to enforce the first-order Karush-Kuhn-Tucker (KKT) conditions through branching. In addition, such an approach naturally
yields linear programming (LP) relaxations at each node. However, the LP relaxations are unbounded, a fact that precludes
their use. In this paper, we propose and study semidefinite programming relaxations, which are bounded and hence suitable
for use with finite KKT-branching. Computational results demonstrate the practical effectiveness of the method, with a particular
highlight being that only a small number of nodes are required.
This author was supported in part by NSF Grants CCR-0203426 and CCF-0545514. 相似文献
950.
We discuss the almost-sure convergence of a broad class of sampling algorithms for multistage stochastic linear programs. We provide a convergence proof based on the finiteness of the set of distinct cut coefficients. This differs from existing published proofs in that it does not require a restrictive assumption. 相似文献