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161.
带模糊约束的最小费用流问题 总被引:3,自引:1,他引:3
本文首次提出了带模糊约束的最小费用流问题,建立了相应的数学模型并给出了求解这一模型的有关算法。最后,给出了一个具体实例。 相似文献
162.
In this paper, we study the weak invariance of the multidimensional rank statistic when the underlying random variables are nonstationary absolutely regular. 相似文献
163.
林一星 《纯粹数学与应用数学》2012,(1):99-108
对拟连续测度空间(G,β,u)的一致有界等度连续函数族,通过包含关系,取凸包和闭包,构造了在Pbkc(c[0,1])与Pbkc(Lp[0,1])取值的集值随机变量及连续的集值映射,深化了集值随机过程理论研究. 相似文献
164.
In the municipal solid waste (MSW) management system, there are many uncertainties associated with the coefficients and their impact factors. Uncertainties can be normally presented as both membership functions and probabilistic distributions. This study develops a scenario-based fuzzy-stochastic quadratic programming (SFQP) model for identifying an optimal MSW management policy and for allowing dual uncertainties presented as probability distributions and fuzzy sets being communicated into the optimization process. It can also reflect the dynamics of uncertainties and decision processes under a complete set of scenarios. The developed method is applied to a case study of long-term MSW management and planning. The results indicate that reasonable solutions have been generated. They are useful for identifying desired waste-flow-allocation plans and making compromises among system cost, satisfaction degree, and constraint-violation risk. 相似文献
165.
This study applies fuzzy sets to integrate the supply chain network of an edible vegetable oils manufacturer. The proposed fuzzy multi-objective linear programming model attempts to simultaneously minimize the total transportation costs. The first part of the total transportation costs is between suppliers and silos; and rest one is between manufacturer and warehouses. The approach incorporates all operating realities and actual flow patterns at production/distribution network with reference to demands of warehouses, capacities of tin and pet packaging lines. The model has been formulated as a multi objective linear programming model where data are modeled by triangular fuzzy numbers. Finally, the developed fuzzy model is applied for the case study, compiled the results and discussed. 相似文献
166.
167.
In this paper, notions of fuzzy closure system and fuzzy closure L —system on L —ordered sets are introduced from the fuzzy point of view. We first explore the fundamental properties of fuzzy closure systems. Then the correspondence between fuzzy closure systems (fuzzy closure L —systems) and fuzzy closure operators is established. Finally, we study the connections between fuzzy closure systems and fuzzy Galois connections. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
168.
Xin Wang Xiaodong Liu Witold PedryczXiaolei Zhu Guangfei Hu 《European Journal of Operational Research》2012,218(1):202-210
In this paper, we propose a novel method to mine association rules for classification problems namely AFSRC (AFS association rules for classification) realized in the framework of the axiomatic fuzzy set (AFS) theory. This model provides a simple and efficient rule generation mechanism. It can also retain meaningful rules for imbalanced classes by fuzzifying the concept of the class support of a rule. In addition, AFSRC can handle different data types occurring simultaneously. Furthermore, the new model can produce membership functions automatically by processing available data. An extensive suite of experiments are reported which offer a comprehensive comparison of the performance of the method with the performance of some other methods available in the literature. The experimental result shows that AFSRC outperforms most of other methods when being quantified in terms of accuracy and interpretability. AFSRC forms a classifier with high accuracy and more interpretable rule base of smaller size while retaining a sound balance between these two characteristics. 相似文献
169.
G. Huber T.A. Vilgis 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,3(2):217-223
The adsorption of a single ideal polymer chain on energetically heterogeneous and rough surfaces is investigated using a variational
procedure introduced by Garel and Orland (Phys. Rev. B 55, 226 (1997)). The mean polymer size is calculated perpendicular and parallel to the surface and is compared to the Gaussian
conformation and to the results for polymers at flat and energetically homogeneous surfaces. The disorder-induced enhancement
of adsorption is confirmed and is shown to be much more significant for a heterogeneous interaction strength than for spatial
roughness. This difference also applies to the localization transition, where the polymer size becomes independent of the
chain length. The localization criterion can be quantified, depending on an effective interaction strength and the length
of the polymer chain.
Received: 29 October 1997 / Revised: 19 December 1997 / Accepted: 6 March 1998 相似文献
170.
V. Korepin N. Slavnov 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,5(3):555-557
We discovered a simple quadratic equation, which relates scattering phases of particles on Fermi surface. We consider one-dimensional
Bose gas and XXZ Heisenberg quantum spin chain.
Received: 4 December 1997 / Accepted: 17 March 1998 相似文献