Exact methods in optimum disassembly sequence search for problems subject to sequence dependent costs

Disassembling complex products is formally approached via network representation and subsequent mathematical modeling, aimed at selecting a good or optimum sequence of disassembly operations. This is done via heuristics, metaheuristics or mathematical programming. In contrast with heuristics and metaheuristics, which select a near-optimum solution, mathematical programming guarantees the selection of the global optimum. This problem is relatively simple if the disassembly costs can be assumed sequence independent. In practice, however, sequence dependent disassembly costs are frequently encountered, which causes NP-completeness of the problem. Although methods, e.g., based on the two-commodity network flow approach, are available to solve this constrained asymmetric Traveling Salesperson problem rigorously, this requires the introduction of integer variables. In this paper, a modification of the two-commodity network flow approach is proposed, which reduces the number of integer variables. This is applied to product structures that can be represented by a disassembly precedence graph. It is demonstrated that use of integer variables is completely avoided by iteratively solving a binary integer linear programming problem. This appears to be more efficient than solving the corresponding integer linear programming problem. It is demonstrated, on the basis of some cases, that this method might provide the exact solution of problems with increased complexity compared to those discussed so far in the literature. This appears particularly useful for evaluating heuristic and metaheuristic approaches.     

论图形的结合方式

具有结合特征的图形形式,往往因符合人们的审美需求而易于获得认可。以在格式塔心理学派的完形理论基础上延伸出的视觉基础理论和经验基础理论为依据,可归纳出三种图形结合方式:以经验基础理论为依据的适形形式,它通过适合人们所获得的经验而进行形与形的结合;以视觉基础理论为依据的融合方式,它利用了人眼在观察物体时所表现出的生理规律而展开图形形式的融合;悖论结合方式则是有意违背常规经验,以此建立起新奇的图形形式。     

政治与经济的整合研究——公共选择理论的方法论及其启示

公共选择理论不仅是当代西方经济学、政治学中的重要理论学派,而且成为当代西方政府改革实践的重要理论基础。公共选择理论将经济学的假说、方法和模式应用于政治领域,对政治过程作出不同于传统政治学理论的解释。这一方法论的独特性是其形成与发展的关键因素和力量源泉,也是它的虚弱所在。研究公共选择理论的方法论,有助于促进社会科学研究中方法论个人主义与方法论集体主义的融合,推动政治与经济的整合研究。     

邓小平行政效率思想述论

本文概括出邓小平同志行政效率思想的三个鲜明特点 ,阐述了邓小平同志对马克思主义关于提高行政效率思想的丰富和发展 ,以及邓小平同志的行政效率思想对于我们进一步深化行政改革、提高行政效率的重要指导意义     

非线性微-积分方程组解的存在惟一性

翻译是人类文化交流行为的主要手段之一。用研究人类行为的博弈理论来审度翻译，有助我们从更宽泛的角度认识翻译的本质和操作手段。“囚徒困境”与“纳什均衡”向我们揭示了翻译的目的与输入性原则，指出翻译中的洋化意向性。     

《二十四诗品》作者考

《二十四诗品》(以下简称《诗品》)确非司空图所作,而是盛唐书画家、书画理论家李嗣真所作。两唐书《艺文志》著录有李嗣真《诗品》一卷,李嗣真《诗品》著作权的缺失,与其生平事迹记载的混乱有关。《诗品》超越时代的诗学意义来源于李嗣真书画家、书画理论家的独特身份和盛唐成熟的书画理论。     

Survey sampling in graphs

The Horvitz-Thompson estimation theory is applied to snowball sampling and some other sampling procedures using a known or unknown graph structure in the survey population. In particular, simple graph-parameter estimators and variance estimators are obtained which are based on various kinds of partial information about the graph.     

An application of information theory to the problem of statistical disclosure

By using prior knowledge it may be possible to deduce pieces of individual information from a frequency distribution of a population. If the prior information is described by a stochastic model, an information-theoretic approach can be applied in order to judge the possibilities for disclosure. By specifying the stochastic model in various ways it is shown how the decrease in entropy caused by the publication of a frequency distribution can be determined and interpreted. The stochastic models are also used to derive formulae for disclosure risks and expected numbers of disclosures.     

On linear regression designs which maximize information

Necessary and sufficient conditions are established when a continuous design contains maximal information for a prescribed s-dimensional parameter in a classical linear model. The development is based on a thorough study of a particular dual problem and its interplay with the optimal design problem, extending partial results and earlier approaches based on differential calculus, game theory, and other programming methods. The results apply in particular to a class of information functionals which covers c-, D-, A-, L-optimality, they include a complete account of the non-differentiable criterion of E-optimality, and provide a constructive treatment of those situations in which the information matrix is singular. Corollaries pertain to the case of s out of k parameters, simultaneous optimality with respect to several criteria, multiplicity of optimal designs, bounds on their weights, and optimality which is induced by admissibility.     

孙中山“权能分别学理”的形成及其基本内涵初探

孙中山“权能分别学理”是国际国内矛盾冲突和孙中山本人文化素养相结合的产物 ,是为解决本国政治权威危机 ,创建驾驭欧美之上的新型良善政制而创造出来的。该学理是孙中山宪法思想的核心与基石 ,其基本内涵包括 :权能分治、人民有权、政府万能、以权驭能和九权平衡四项原则 ,全方位体现了中西政治文化共同尊崇的宪法基本精神———和谐。