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941.
For the case of initial data in the problem of group choice represented as fuzzy partial orderings two problems are solved: (1) design of a set group decisions which satisfy the Pareto unanimity principlle and stay ‘halfway’ between initial relations and (2) design of a unique group decision. 相似文献
942.
The applicability of Kramers-Kronig (K-K) relation under nearly sharp resonant transition regime in narrow-gap semiconductors
has been established and consequently, a generalized dispersion relation for nonlinear optical susceptibility of a dielectric
is derived. This relation can be employed in the study of nonlinear optical processes in solids as well as in plasmas over
a wide frequency spectrum. 相似文献
943.
It is well known that a simple relation called proportional relation holds for some queueing models, that is, the stationary queue length distribution of one system can be expressed as the product of a constant and the distribution of another system which is different only in the buffer capacity. Recently, the proportional relation has been verified for various discrete-time single-server queues with correlated arrivals, where it has been also shown that the proportional constant can be expressed in terms of the distribution of one system. This implies that the stationary queue length distribution of one system can be completely expressed in terms of the distribution of the other system. In this paper, we consider a generalized model of discrete-time single-server queue, which covers all previous ones, and give a simple and unified proof to the proportional relation as well as the expression of the proportional constant. 相似文献
944.
Robert E. Jamison 《Discrete Mathematics》2005,290(1):27-46
A chordal graph is the intersection graph of a family of subtrees of a host tree. In this paper we generalize this. A graph G=(V,E) has an (h,s,t)-representation if there exists a host tree T of maximum degree at most h, and a family of subtrees {Sv}v∈V of T, all of maximum degree at most s, such that uv∈E if and only if |Su∩Sv|?t. For given h,s, and t, there exist infinitely many forbidden induced subgraphs for the class of (h,s,t)-graphs. On the other hand, for fixed h?s?3, every graph is an (h,s,t)-graph provided that we take t large enough. Under certain conditions representations of larger graphs can be obtained from those of smaller ones by amalgamation procedures. Other representability and non-representability results are presented as well. 相似文献
945.
James J. Y. Zhao 《数学学报(英文版)》2016,32(5):553-558
Let {P_n}n≥0 denote the Catalan-Larcombe-French sequence,which naturally came from the series expansion of the complete elliptic integral of the first kind.In this paper,we prove the strict log-concavity of the sequence {P_n~(1/n)}_n≥1,which was originally conjectured by Z.W.Sun.We also obtain the strict log-concavity of the sequence {V_n~(1/n)}_n≥1,where {V_n}_n≥0 is the Fennessey-LarcombeFrench sequence arising from the series expansion of the complete elliptic integral of the second kind. 相似文献
946.
Lili Zhang 《Discrete Mathematics》2008,308(24):6588-6595
Let G be an infinite graph embedded in a surface such that each open face of the embedding is homeomorphic to an open disk and is bounded by finite number of edges. For each vertex x of G, we define the combinatorial curvature
947.
Mohamed Barraa 《Journal of Mathematical Analysis and Applications》2008,347(1):315-322
In this paper we investigate perturbations of the regular spectrum of an upper triangular operator matrix such as acting on a Hilbert space H⊕K. 相似文献
948.
Seok-Zun Song Kyung-Tae Kang LeRoy B. Beasley Nung-Sing Sze 《Linear algebra and its applications》2008,429(1):209-223
An m×n matrix A over a semiring is called regular if there is an n×m matrix G over such that AGA=A. We study the problem of characterizing those linear operators T on the matrices over a semiring such that T(X) is regular if and only if X is. Complete characterizations are obtained for many semirings including the Boolean algebra, the nonnegative reals, the nonnegative integers and the fuzzy scalars. 相似文献
949.
Abel's lemma on summation by parts is reformulated to investigate systematically terminating theta hypergeometric series. Most of the known identities are reviewed and several new transformation and summation formulae are established. The authors are convinced by the exhibited examples that the iterating machinery based on the modified Abel lemma is powerful and a natural choice for dealing with terminating theta hypergeometric series. 相似文献
950.
基于灰色关联分析和主成分分析组合权重的确定方法研究 总被引:3,自引:0,他引:3
为了提高综合评价模型中权重的准确性和客观性,以主成分分析法和灰色关联分析法为基础,建立了组合权重模型,从而修正了灰色关联分析法和主成分分析法在确定权重过程中的缺陷,为综合评价体系中权重的确定提出一种新的思路. 相似文献