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931.
James T. Yen 《Journal of statistical physics》1972,5(1-2):1-18
The Gibbsian relation is of fundamental importance to the thermodynamics of nonequilibrium systems. In this paper, we shall present an analytical derivation and several generalizations of this relation for dilute, nonequilibrium and certain highly nonequilibrium, systems. Our analysis will beindependent of the collision dynamics, because it will be based on the general kinetic equation witharbitrary collision integrals. Consequently, our analysis can provide athermodynamic derivation and several generalizations of the Gibbsian relation. Our distribution functions can also admit some arbitrary, nonequilibrium and highly nonequilibrium, forms. With the help of the generalized Gibbsian relation and a fundamental axiom to be postulated, the entropy production rates and the generalized forces and fluxes will be studied for our highly nonequilibrium systems. The second law of thermodynamics will be postulated and verified in specific cases. Onsager's reciprocity relations will be discussed. 相似文献
932.
Hong Sun Yingwu Tang Fushi Zhang Guoshi Wu Shek‐Kiu Chan 《Journal of Polymer Science.Polymer Physics》2002,40(19):2164-2169
Fuzzy set theory was used to study the relationship between the glass‐transition temperature (Tg) and structure of homopolymers. The method can map the relationship and give the Tg for 235 polymers with a standard deviation of 8 K (the confidence bound was 90%). The entropy of the fuzziness was used to quantitatively describe the interactions among groups. The method was used to predict the Tg of 10 polymers not included in the 235 polymers, with a standard deviation of 9 K (the confidence bound was 90%). The study demonstrates again that fuzzy set theory can be effectively used to investigate the quantitative structure–property relationship of polymers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2164–2169, 2002 相似文献
933.
934.
Xin Rong Ma 《数学学报(英文版)》2002,18(2):289-292
With an effort to investigate a unified approach to the Lagrange inverse Krattenthaler established operator method we finally
found a general pair of inverse relations, called the Krattenthaler forumlas. The present paper presents a very short proof
of this formula via Lagrange interpolation. Further, our method of proof declares that the Krattenthaler result is unique
in the light of Lagrange interpolation.
Received April 9, 1999, Accepted December 7, 2000 相似文献
935.
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
936.
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
937.
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
938.
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
939.
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
940.
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