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931.
The desirability function is widely used in the engineering field to tackle the problem of optimizing multiple responses simultaneously. This approach does not account for the variability in the predicted responses and minimizing this variability to have narrower prediction intervals is desirable. We propose to add this capability in the desirability function and also incorporate the relative importance of optimizing the multiple responses and minimizing the variances of the predicted responses at the same time. We show that the benefits of our augmented approach using two real data sets by comparing our solutions with those obtained from the desirability approach. In particular, it is shown that our approach offers greater flexibility and the solutions can reduce the variances of all the predicted responses resulting in narrower prediction intervals. 相似文献
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N. Bourgeois F. Della Croce B. Escoffier C. Murat V. Th. Paschos 《Journal of Combinatorial Optimization》2009,17(3):274-311
We revisit in this paper the stochastic model for minimum graph-coloring introduced in (Murat and Paschos in Discrete Appl.
Math. 154:564–586, 2006), and study the underlying combinatorial optimization problem (called probabilistic coloring) in bipartite and split graphs. We show that the obvious 2-coloring of any connected bipartite graph achieves standard-approximation
ratio 2, that when vertex-probabilities are constant probabilistic coloring is polynomial and, finally, we propose a polynomial algorithm achieving standard-approximation ratio 8/7. We also handle
the case of split graphs. We show that probabilistic coloring is NP-hard, even under identical vertex-probabilities, that it is approximable by a polynomial time standard-approximation schema
but existence of a fully a polynomial time standard-approximation schema is impossible, even for identical vertex-probabilities,
unless P=NP. We finally study differential-approximation of probabilistic coloring in both bipartite and split graphs.
Part of this research has been performed while the second author was with the LAMSADE on a research position funded by the
CNRS. 相似文献
936.
Saman Eskandarzadeh Reza Tavakkoli-Moghaddam Amir Azaron 《Journal of Combinatorial Optimization》2009,17(2):214-234
In this paper, we propose an exact method for solving a special integer program associated with the classical capacitated
arc routing problems (CARPs) called split demand arc routing problems (SDARP). This method is developed in the context of
monotropic programming theory and bases a promising foundation for developing specialized algorithms in order to solve general
integer programming problems. In particular, the proposed algorithm generalizes the relaxation algorithm developed by Tseng
and Bertsekas (Math. Oper. Res. 12(4):569–596, 1987) for solving linear programming problems. This method can also be viewed as an alternative for the subgradient method for
solving Lagrangian relaxed problems. Computational experiments show its high potential in terms of efficiency and goodness
of solutions on standard test problems. 相似文献
937.
A multiagent fusion search is presented for the graph coloring problem. In this method, each of agents performs the fusion
search, involving a local search working in a primary exploitation role and a recombination search in a navigation role, with
extremely limited memory and interacts with others through a decentralized protocol, thus agents are able to explore in parallel
as well as to achieve a collective performance. As the knowledge components implemented with available structural information
and in formalized forms, the Quasi-Tabu local search and grouping-based recombination rules are especially useful in addressing
neutrality and ruggedness of the problem landscape. The new method has been tested on some hard benchmark graphs, and has
been shown competitive in comparison with several existing algorithms. In addition, the method provides new lower bound solutions
when applied to two large graphs. Some search characteristics of the proposed method is also discussed. 相似文献
938.
汶川特大地震灾后社区心理援助的统筹优选模式 总被引:1,自引:0,他引:1
汶川特大地震使灾区城镇和农村原有的社区基本被破坏甚至毁灭,通过对灾后社区展开问卷调查和访谈,运用SPSS统计分析软件,找出灾后社区心理援助的关键问题。在以人为本的科学发展观的统领下,依据统筹优选的思想与方法,以在最短的时间内投入最少精力,运用最有效的方法取得最佳援助效果为目的,分析灾后社区心理援助的解决思路,构建灾后社区心理援助的基本框架,提出灾后社区心理援助的统筹优选模式。该模式包括灾后心理评估体系和灾后社区心理援助过程2个方面,前者由灾后心理评估和援助效果评估2个部分组成;后者包括初期心理援助、中期心理援助和长期心理援助3个阶段,分别从援助主客体、援助内容和援助方法来进行分析研究,实现对地震灾后社区的心理援助。 相似文献
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本文对基于银行授信额度的Max-NPV项目调度问题进行研究.首先界定研究的假设条件并对文中所用到的符号进行定义;随后采用基于事件的研究方法构建了问题的整数规划优化模型;鉴于问题的NP-hard属性,设计了双层模拟退火搜索循环嵌套的启发式求解算法;最后对一个算例进行了求解分析,并讨论了银行授信额度及客户支付比例对项目收益的影响.结果表明:随着银行授信额度的提高,承包商安排项目进度自由度的增加使得其净现值得到改善,在支付比例较低的条件下项目完成时间也随之提前;当客户支付比例提高时,项目净现值单调上升,而项目完成时间呈先提前后延迟的变化趋势. 相似文献