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91.
Recombination of charge carriers in a?SiHx Schottky barriers with density of states near mid-gap ranging from 2.8×1015?7×1016cm-1eV-1 is attributed to recombination centers with hole capture cross-section of 1.3×10-15cm2. 相似文献
92.
It is proposed to define entropy for nonequilibrium ensembles using a method of coarse graining which partitions phase space into sets which typically have zero measure. These are chosen by considering the totality of future possibilities for observation on the system. It is shown that this entropy is necessarily a nondecreasing function of the timet. There is no contradiction with the reversibility of the laws of motion because this method of coarse graining is asymmetric under time reversal. Under suitable conditions (which are stated explicitly) this entropy approaches the equilibrium entropy ast+ and the fine-grained entropy ast–. In particular, the conditions can always be satisfied if the system is aK-system, as in the Sinai billiard models. Some theorems are given which give information about whether it is possible to generate the partition used here for coarse graining from time translates of a finite partition, and at the same time elucidate the connection between our concept of entropy and the entropy invariant of Kolmogorov and Sinai.Research supported in part by NSF grants PHY78-03816 and PHY78-15920. 相似文献
93.
Larry Guth 《Geometric And Functional Analysis》2007,17(4):1139-1179
We prove that a bounded open set U in has k-width less than C(n) Volume(U)
k/n
. Using this estimate, we give lower bounds for the k-dilation of degree 1 maps between certain domains in . In particular, we estimate the smallest (n – 1)-dilation of any degree 1 map between two n-dimensional rectangles. For any pair of rectangles, our estimate is accurate up to a dimensional constant C(n). We give examples in which the (n – 1)-dilation of the linear map is bigger than the optimal value by an arbitrarily large factor.
Received: January 2006, Revision: May 2006, Accepted: June 2006 相似文献
94.
For 0≤k≤n, let be the entries in Euler’s difference table and let . Dumont and Randrianarivony showed equals the number of permutations on [n] whose fixed points are contained in {1,2,…,k}. Rakotondrajao found a combinatorial interpretation of the number in terms of k-fixed-points-permutations of [n]. We show that for any n≥1, the sequence is essentially 2-log-concave and reverse ultra log-concave. 相似文献
95.
96.
Sheldon Goldstein Roelof Kuik Joel L. Lebowitz Christian Maes 《Communications in Mathematical Physics》1989,125(1):71-79
Stationary measures for probabilistic cellular automata (PCA's) ind dimensions give rise to space-time histories whose statistics may naturally be described by Gibbs states ind+1 dimensions for an interaction energy ? obtained from the PCA. In this note we study the converse question: Do all Gibbs states for this ? correspond to statistical space-time histories for the PCA? Our main result states that the answer is yes, at least for translation invariant or periodic Gibbs states. Thus ergodicity questions for PCA's can, at least partially, be formulated as questions of uniqueness of Gibbs states. 相似文献
97.
Summary. We derive error bounds for bivariate spline interpolants which are calculated by minimizing certain natural energy norms.
Received March 28, 2000 / Revised version received June 23, 2000 / Published online March 8, 2002
RID="*"
ID="*" Supported by the National Science Foundation under grant DMS-9870187
RID="**"
ID="**" Supported by the National Science Foundation under grant DMS-9803340 and by the Army Research Office under grant DAAD-19-99-1-0160 相似文献
98.
99.
Pawe Goldstein Pawe Strzelecki Anna Zatorska-Goldstein 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2009,26(4):1387-1405
We prove that every polyharmonic map u∈Wm,2(Bn,SN−1) is smooth in the critical dimension n=2m. Moreover, in every dimension n , a weak limit u∈Wm,2(Bn,SN−1) of a sequence of polyharmonic maps uj∈Wm,2(Bn,SN−1) is also polyharmonic. 相似文献
100.
Larry Jenkins 《Annals of Operations Research》1990,27(1):77-96
In contrast to methods of parametric linear programming which were developed soon after the invention of the simplex algorithm and are easily included as an extension of that method, techniques for parametric analysis on integer programs are not well known and require considerable effort to append them to an integer programming solution algorithm.The paper reviews some of the theory employed in parametric integer programming, then discusses algorithmic work in this area over the last 15 years when integer programs are solved by different methods. A summary of applications is included and the article concludes that parametric integer programming is a valuable tool of analysis awaiting further popularization. 相似文献