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991.
Global optimization problems involving the minimization of a product of convex functions on a convex set are addressed in
this paper. Elements of convex analysis are used to obtain a suitable representation of the convex multiplicative problem
in the outcome space, where its global solution is reduced to the solution of a sequence of quasiconcave minimizations on
polytopes. Computational experiments illustrate the performance of the global optimization algorithm proposed.
相似文献
992.
Nenad Mladenović Milan Dražić Vera Kovačevic-Vujčić Mirjana Čangalović 《European Journal of Operational Research》2008
We suggest a new heuristic for solving unconstrained continuous optimization problems. It is based on a generalized version of the variable neighborhood search metaheuristic. Different neighborhoods and distributions, induced from different metrics are ranked and used to get random points in the shaking step. We also propose VNS for solving constrained optimization problems. The constraints are handled using exterior point penalty functions within an algorithm that combines sequential and exact penalty transformations. The extensive computer analysis that includes the comparison with genetic algorithm and some other approaches on standard test functions are given. With our approach we obtain encouraging results. 相似文献
993.
We consider an approach for ex post evaluation of approximate solutions obtained by a well known simple greedy method for
set packing. A performance bound is derived that is a function of the highest average reward per item over subsets as well
as the number of allocated subsets and ground items. This a posterior bound can enable much revelation of optimality when
the solution is near optimal. One of the advantages of the ex post analysis is that it does not require computing the optimal
solution to the LP relaxation. The ex post bound will not be guaranteed to reveal substantial levels of optimality for all
problem instances but can be a useful tool that is complementary to other traditional methods for ex post evaluation for the
set packing problem. 相似文献
994.
分析了自卸车装载混凝土难卸的原因 ,针对性地设计了一种快速卸载装置 该装置仅由上摆板、下滑板和铰链组成 ,结构简单 ,安装使用方便 ,生产试验表明其具有良好的效果 相似文献
995.
DevelopmentofaSupportToolforRapidApplicationIntegrationofCIMS*FanYushun(范玉顺),WuCheng(吴澄)DepartmentofAutomation,TsinghuaUniver... 相似文献
996.
通过对“计算机等级考试(操作测试)自动阅卷系统”编程环境分析研究,探讨混合编程方式下存储模式、编译模式、混合编程接口及外部连接的一些规律,给出在阅卷系统中处理以上问题的方法。 相似文献
997.
We propose a novel approach for solving polynomial programs over compact domains with equality constraints. By means of a generic transformation, we show that existing solution schemes for the, typically simpler, problem without equalities can be used to address the problem with equalities. 相似文献
998.
A modification of a solution concept of the linear programming problem with interval coefficients in the constraints 总被引:1,自引:0,他引:1
Dorota Kuchta 《Central European Journal of Operations Research》2008,16(3):307-316
We propose a modification of a concept of solving a linear programming problem with interval coefficients in the constraints.
The original concept imposes the decision maker a way comparing intervals, our modification—which is an interactive approach,
comprising the original one as its special case—gives him more freedom in the choice of the preference relation. Thanks to
this flexibility he may be able to find a solution which better suits his needs and attitude towards risk. What is more, our
modification corrects a serious drawback of the original method. 相似文献
999.
We consider the class of quadratically-constrained quadratic-programming methods in the framework extended from optimization
to more general variational problems. Previously, in the optimization case, Anitescu (SIAM J. Optim. 12, 949–978, 2002) showed superlinear convergence of the primal sequence under the Mangasarian-Fromovitz constraint qualification and the quadratic
growth condition. Quadratic convergence of the primal-dual sequence was established by Fukushima, Luo and Tseng (SIAM J. Optim.
13, 1098–1119, 2003) under the assumption of convexity, the Slater constraint qualification, and a strong second-order sufficient condition.
We obtain a new local convergence result, which complements the above (it is neither stronger nor weaker): we prove primal-dual
quadratic convergence under the linear independence constraint qualification, strict complementarity, and a second-order sufficiency
condition. Additionally, our results apply to variational problems beyond the optimization case. Finally, we provide a necessary
and sufficient condition for superlinear convergence of the primal sequence under a Dennis-Moré type condition.
Research of the second author is partially supported by CNPq Grants 300734/95-6 and 471780/2003-0, by PRONEX–Optimization,
and by FAPERJ. 相似文献
1000.
Satya Prakash Pranav Kumar B.V.N.S. Prasad Anuj Gupta 《European Journal of Operational Research》2008
A cost–time trade-off bulk transportation problem with the objectives to minimize the total cost and duration of bulk transportation without according priorities to them is considered. The entire requirement of each destination is to be met from one source only; however a source can supply to any number of destinations subject to the availability of the commodity at it. Two new algorithms are provided to obtain the set of Pareto optimal solutions of this problem. This work extends and generalizes the work related to single-objective and prioritized two-objective bulk transportation problems done in the past while providing flexibility in decision making. 相似文献