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1.
The degree of difficulty in solving a global optimization problem is in general dependent on the dimensionality of the problem and certain characteristics of the objective function. This paper discusses five of these characteristics and presents a strategy for function optimization called the shuffled complex evolution (SCE) method, which promises to be robust, effective, and efficient for a broad class of problems. The SCE method is based on a synthesis of four concepts that have proved successful for global optimization: (a) combination of probabilistic and deterministic approaches; (b) clustering; (c) systematic evolution of a complex of points spanning the space, in the direction of global improvement; and (d) competitive evolution. Two algorithms based on the SCE method are presented. These algorithms are tested by running 100 randomly initiated trials on eight test problems of differing difficulty. The performance of the two algorithms is compared to that of the controlled random search CRS2 method presented by Price (1983, 1987) and to a multistart algorithm based on the simplex method presented by Nelder and Mead (1965).This work was partially funded by the National Science Foundation, Grant ECE-86-10584, and by the National Weather Service, Grant NA85AA-H-HY088.  相似文献
2.
平行机半在线排序问题研究(Ⅰ)   总被引:15,自引:1,他引:14  
对半在线平行机排序问题的研究进展作了详细综述和进一步探讨。文章给出半在线排序问题的背景、定义、分类和求解。介绍它们定义和在不同机器环境和目标函数下半在线排序问题分类,以及第一类半在线模型的近似算法的设计及其竞争比分析。  相似文献
3.
平行机半在线排序问题研究(Ⅱ)   总被引:15,自引:1,他引:14  
继续介绍半在线平行机排序问题的研究进展.主要介绍第二类、第三类半在线模型.研究两个(或两个以上)半在线模型间关系:复合与限制.文章最后给出了一些待研究的问题。  相似文献
4.
深入开展中学生数学知识应用活动   总被引:15,自引:4,他引:11  
本文是作者在"第七届全国数学建模教学与应用会议”的发言写成的,内容包括对以下四个问题的论述中学生数学知识应用竞赛;中学数学知识应用教学单元的编写;美国的中学生数学知识应用竞赛;从西屋科学奖到英特尔科学奖.  相似文献
5.
多物种生态竞争系统周期正解的存在性和全局吸引性   总被引:12,自引:0,他引:12       下载免费PDF全文
范猛  王克 《数学学报》2000,43(1):77-82
利用重合度理论中的延拓定理和Lyapunov泛函方法讨论了一类具有多个滞量的多物种生态竞争系统周期正解的存在性和全局吸引性,得到了一些新的结果.实例表明我们的结果更加广泛,更加便于应用.  相似文献
6.
企业竞争力评价的投影寻踪模型   总被引:11,自引:0,他引:11  
建立了企业竞争能力评价的投影寻踪聚类模型,利用该模型可将企业竞争优势评价的多个指标转换为反映各指标综合信息的投影特征值,根据投影特征值的大小便可对企业竞争能力进行客观评价,整个过程无人为干扰。通过对5个煤炭企业竞争优势评价表明该方法操作简便,切实可行,为企业竞争能力综合评价的多因素影响问题提供了一条新途径。  相似文献
7.
On the on-line rent-or-buy problem in probabilistic environments   总被引:11,自引:0,他引:11  
Fujiwara and Iwama [In: The 13th Annual International Symposium on Algorithms and Computation, pp. 476–488 (2002)] first integrated probability distribution into the classical competitive analysis to study the rental problem. They assumed that the future inputs are drawn from an exponential distribution, and obtained the optimal competitive strategy and the competitive ratio by the derivative method. In this paper, we introduce the interest rate and tax rate into the continuous model of Fujiwra and Iwama [In: The 13th Annual International Symposium on Algorithms and Computation, pp. 476–488 (2002)]. Moreover, we use the forward difference method in different probabilistic environments to consider discrete leasing models both with and without the interest rate. We not only give the optimal competitive strategies and their competitive ratios in theory, but also give numerical results. We find that with the introduction of the interest rate and tax rate, the uncertainty involved in the process of decision making will diminish and the optimal purchasing date will be put off.  相似文献
8.
用列队竞争算法解旅行商问题   总被引:10,自引:1,他引:9  
给出了列队竞争算法解组合优化问题的框架和确定变异邻域的两条原则。用列队竞争算法解旅行商问题获得了满意的结果,显示出列队竞争算法良好的全局搜索性能。  相似文献
9.
多种群生态竞争-捕食时滞系统正周期解的全局吸引性   总被引:10,自引:0,他引:10       下载免费PDF全文
文贤章 《数学学报》2002,45(1):83-92
本文利用比较定理结合Liapunov泛函的方法, 讨论一类具有多个时滞的多种群生态竞争-捕食系统正周期解的存在性和全局吸引性,得到了一些新的结果, 并举例说明条件的可行性.  相似文献
10.
Researchers and managers have been searching for appropriate methods to explore the relationship between technological innovation capability and competitiveness in recent years. This study attempts to find a systematic quantitative methodology to tackle this problem. In a recent survey covering 182 industrial innovative firms in China, the traditional data envelopment analysis (DEA) model was employed to analyze the data collected. The research results show that only 16% of the enterprises operate on the best-practice frontier and there are some inconsistencies between organizational innovation capability and competitiveness in many enterprises. Decreasing returns to scale were found among about 70% of the inefficient enterprises and increasing returns to scale were found among the remaining 30% of the inefficient enterprises. Thus the internal innovation harmonizing process in these enterprises is considerably inefficient. Based on the restricted ranges of the input/output factors, a multi-objective DEA projection model has also been developed in this study to provide a benchmark for auditing competitiveness. Research results further indicate that there is still much room for enterprises to improve competitiveness in situations of confining score ranges of technological innovation capability and competitiveness.  相似文献
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