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111.
Theories on Solving the Travelling Salesman Problem Based on Artificial Neural Network and Their Applications 总被引:1,自引:0,他引:1
NPhardproblemshaveappearedinmanyareas.Inthisarticle,itisdiscusedhowtosolvethiskindofproblemsusingartificialneuralnetwork—Hop... 相似文献
112.
文中介绍了TD-SCDMA信令测试仪中一种基于NP网络处理器的STM-1数据采集卡的实现方案,主要分析了STM-1数据采集卡的各个模块,详细说明了数据采集卡的数据处理流程。 相似文献
113.
Igor G. Zenkevich Andrew A. Makarov Steffi Schrader Monika Moeder 《Journal of chromatography. A》2009,1216(18):4097-4106
Control of environmental pollution by 4-nonylphenols (4-NP) and effective risk assessment concerning these xenoestrogens requires the identification of the individual isomers contained in the technical mixtures of 4-NP. A new approach is presented here which supports the identification of these compounds by a combination of experimentally determined gas chromatographic retention indices (I) of reference 4-NP isomers and calculated I-values. In addition to experimental indices, the I-prediction algorithm includes a new version of an additive scheme. The I-values of all structural 4-NP isomers are calculated on the basis of experimentally determined indices of a few available 4-NP isomers and the known retention indices of 75 iso-decanes. A mean deviation of ±11 index units between predicted and experimental I-values demonstrates the feasibility of the new approach. The predicted I-values provide information on the structure of 4-nonylphenol isomers in the technical mixture which has not been considered before. Furthermore, a novel line-coding system is proposed to describe the structure of isomeric 4-NPs and to initiate a current database for the endocrine-disrupting 4-nonylphenols. 相似文献
114.
现代物流技术中装卸工问题的拟多项式时间可解情况 总被引:10,自引:0,他引:10
装卸工问题是从现代物流技术中提出的一个实际问题,这个问题的雏形早在上个世纪60年代中国科学院数学研究所就提出和研究过。现代物流业的迅速发展,促成和推动装卸工问题的提出和研究。装卸工问题是一个新的NP困难的组合优化问题,本文研究限制情形下的装卸工问题,并证明是拟多项式时间可解的。 相似文献
115.
装卸工问题是从现代物流技术中提出的一个实际问题,这个问题的雏形早在上个世纪60年代中国科学院数学研究所就提出和研究过.现代物流技术迅速发展,促成和推动装卸工问题的提出和研究.装卸工问题是一个新的NP困难的组合优化问题,首先介绍装卸工问题及限制情况下装卸工问题的数学模型,然后分析限制情况下的装卸工问题的性质,最后给出该问题的所有最优解. 相似文献
116.
Drago Bokal Gasper Fijavz Martin Juvan P. Mark Kayll Bojan Mohar 《Journal of Graph Theory》2004,46(3):227-240
We introduce the circular chromatic number χc of a digraph and establish various basic results. They show that the coloring theory for digraphs is similar to the coloring theory for undirected graphs when independent sets of vertices are replaced by acyclic sets. Since the directed k‐cycle has circular chromatic number k/(k – 1), for k ≥ 2, values of χc between 1 and 2 are possible. We show that in fact, χc takes on all rational values greater than 1. Furthermore, there exist digraphs of arbitrarily large digirth and circular chromatic number. It is NP‐complete to decide if a given digraph has χc at most 2. © 2004 Wiley Periodicals, Inc. J Graph Theory 46: 227–240, 2004 相似文献
117.
Morteza Moniri 《Mathematical Logic Quarterly》2003,49(4):425-427
IPV is the intuitionistic theory axiomatized by Cook's equational theory PV plus PIND on NP‐formulas. Two extensions of IPV were introduced by Buss and by Cook and Urquhart by adding PIND for formulas of the form A(x) ∨ B, respectively ¬¬A(x), where A(x) is NP and x is not free in B. Cook and Urquhart posed the question of whether these extensions are proper. We show that in each of the two cases the extension is proper unless the polynomial hierarchy collapses. 相似文献
118.
119.
Rice's Theorem says that every nontrivia semantic property of programs is undecidable. In this spirit we show the following: Every nontrivia absolute (gap, relative) counting property of circuits is UP‐hard with respect to polynomial‐time Turing reductions. For generators [31] we show a perfect analogue of Rice's Theorem. 相似文献
120.