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671.
672.
Rajat Deb 《Mathematical Social Sciences》1983,5(1):97-105
The concept of numerical representability of preferences together with maximality is at the heart of the concept of rationality embodied in classical optimization models. The difficulty of representing social preferences arises from inherent intransitivities thrown up by democratic voting procedures and by non-binary choice rules which need to be adopted to cope with these intransitivities. An alternative (weaker) concept of representability is developed and it is shown that this concept can partially accommodate intransitivity and non-binariness. ‘Weak transitivity’ and ‘weak binaries’ conditions are provided and it is shown that these conditions are necessary and sufficient for ‘weak representability’. While the weak transitivity condition would be violated by social aggregation procedures, the non-binary functions used by social choice theorists do indeed satisfy the condition of ‘weak binariness’. 相似文献
673.
沈永祥 《新疆大学学报(理工版)》1987,(1)
本文将在弹性平面上(有限或无限)带有p个任意裂缝又带有m个任意孔的且位移是相对位移的混合问题转化为奇异积分方程,证明了问题解的存在与唯一性,并且给出了解法。 相似文献
674.
In the present analysis of Welcher–Weg (WW) measurements, momentum transfer effects are taken into account. Although the WW apparatus that determines which-way might not include any momentum transfer, there is a momentum transfer to the macroscopic entangled parts of the system (beam-splitter and mirrors in Mach–Zehnder interferometer or macroscopic double-slit wall in 2-slit experiments). We show how a measurement in one location (the WW apparatus) influences the wavefunction at another location (the beam-splitter or 2-slit wall) and fixes momentum at that second place, exactly as that of the EPR effect. 相似文献
675.
We consider in Hilbert spaces linear ill-posed problems Ax = y with noisy data y
satisfying y
–y. Regularized approximations x
r
to the minimum-norm solution x
of Ax = y are constructed by continuous regularization methods or by iterative methods. For the choice of the regularization parameter r (the stopping index n in iterative methods) the following monotone error rule (ME rule) is used: we choose r = r
ME (n = n
ME) as the largest r-value with the guaranteed monotonical decrease of the error x
r
– x
for r [0, r
ME] (x
n
– x
<#60; x
n–1
– x
for n = 1, 2, ..., n
ME). Main attention is paid to iterative methods of gradient type and to nonstationary implicit iteration methods. As shown, the ME rule leads for many methods to order optimal error bounds. Comparisons with other rules for the choice of the stopping index are made and numerical examples are given.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
676.
677.
The existence of free ultrafilters on ω does not imply the extension of filters on ω to ultrafilters
Eric J. Hall Kyriakos Keremedis Eleftherios Tachtsis 《Mathematical Logic Quarterly》2013,59(4-5):258-267
Let X be an infinite set and let and denote the propositions “every filter on X can be extended to an ultrafilter” and “X has a free ultrafilter”, respectively. We denote by the Stone space of the Boolean algebra of all subsets of X. We show:
- 相似文献
678.
研究了Suzumura一致性选择函数的展示偏好描述,在已有的展示偏好定义基础上,给出了Suzumura一致性选择函数的展示偏好公理,并证明了该公理是Suzumura一致性选择函数理性化的充要条件. 相似文献
679.
For a graph G, let be the maximum number of vertices of G that can be colored whenever each vertex of G is given t permissible colors. Albertson, Grossman, and Haas conjectured that if G is s‐choosable and , then . In this article, we consider the online version of this conjecture. Let be the maximum number of vertices of G that can be colored online whenever each vertex of G is given t permissible colors online. An analog of the above conjecture is the following: if G is online s‐choosable and then . This article generalizes some results concerning partial list coloring to online partial list coloring. We prove that for any positive integers , . As a consequence, if s is a multiple of t, then . We also prove that if G is online s‐choosable and , then and for any , . 相似文献
680.
Myriam Merad Nicolas Dechy Lisa Serir Michel Grabisch Frédéric Marcel 《European Journal of Operational Research》2013
The implementation of Sustainable Development (SD) within an Organization is a difficult task. This is due to the fact that it is difficult to deal with conflicting and incommensurable aspects such as environmental, economic and social dimensions. In this paper we have used a Multi-Criteria Decision Aid (MCDA) methodology to cope with these difficulties. MCDA methodology offers the opportunity to avoid monetary valuation of the different dimensions of the SD. These dimensions are not substitutable for one another and all have a role to play. There is an abundance of possible aggregation procedures in MCDA methodology. In this paper we have proposed an innovative method to choose a suitable aggregation procedure for SD problems. Real life case studies of the implementation of an outranking approach (i.e., ELECTRE) and of a mono-criterion synthesis approach (i.e., MAUT approaches based on the Choquet integral) were done to respectively rank 22 SD strategic actions within an expertise Institute and rank 20 practical operational actions to control energy consumption of the Institute’s buildings. 相似文献