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991.
We give some multidimensional Tauberian theorems for generalized functions and show examples of their application in mathematical physics. In particular, we consider the problems of stabilizing the solutions of the Cauchy problem for the heat kernel equation, multicomponent gas diffusion, and the asymptotic Cauchy problem for a free Schrödinger equation in the norms of different Banach spaces among others. 相似文献
992.
Ricard Martí 《Journal of Combinatorial Theory, Series A》2008,115(4):547-568
Let k=Fq be a finite field. We enumerate k-rational n-sets of (unordered) points in a projective space PN over k, and we compute the generating function for the numbers of PGLN+1(k)-orbits of these n-sets. For N=1,2 we obtain a formula for these numbers of orbits as a polynomial in q with integer coefficients. 相似文献
993.
Shigeto Nishimura 《Discrete Applied Mathematics》2008,156(12):2352-2358
In this contribution the Riemann hypothesis analogue presented by Iwan Duursma is considered. Whether the analogue for a given selfdual code holds depends on its Hamming weight enumerator. A necessary and sufficient condition is provided in the case of genus less than 3 for the homogeneous polynomials in two variables invariant under the MacWilliams transform. Also the case of half integral genus is studied and similar results are obtained. 相似文献
994.
S. Kumar 《Acta Mathematica Hungarica》2008,118(1-2):9-28
We prove expansion mappings theorems in various spaces i.e., metric spaces, generalized metric spaces, probabilistic metric
spaces and fuzzy metric spaces, which generalize the results of various authors like Daffer and Kaneko [11], Ahmad, Ashraf
and Rhoades [1], Vasuki [38], Rhoades [31] and Wang, Li, Gao and Iseki [40] etc.
In the memory of 65th birthday anniversary of his Father Late Sh. Ram Phool Sharma 相似文献
995.
Paula Cerejeiras Uwe Kähler Vladislav V. Kravchenko 《Mathematical Methods in the Applied Sciences》2008,31(14):1722-1738
A general scheme for factorizing second‐order time‐dependent operators of mathematical physics is given, which allows a reduction of corresponding second‐order equations to biquaternionic equations of first order. Examples of application of the proposed scheme are presented for both constant and variable coefficients. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
996.
用一种统一的方式,讨论了线性规划问题中常用的罚函数方法及其对偶性.并将这种方法应用到等式约束二次规划问题中. 相似文献
997.
We propose the test statistic to check whether the nonparametric func-tions in two partially linear models are equality or not in this paper. We estimate the nonparametric function both in null hypothesis and the alternative by the local linear method, where we ignore the parametric components, and then estimate the parameters by the two stage method. The test statistic is derived, and it is shown to be asymptotically normal under the null hypothesis. 相似文献
998.
Aiming to provide an appropriate number K of clusters, in this paper, we propose a new criterion function - H criterion function, whose three properties have also been proved. We validate the performance of the H criterion function on one artificial dataset and three real-world datasets, and the results are almostly consistent with a previous method. The nonparametric criterion we proposed is intuitive, simple and the computational cost is acceptable. 相似文献
999.
A. L. Kuz’mina 《Russian Mathematics (Iz VUZ)》2008,52(7):8-14
We study Besicovitch-type spaces of generalized almost periodic functions. The main result is a theorem on representation of linear continuous functionals that is similar to the classical result of F. Riesz. 相似文献
1000.
In this letter, a new auxiliary function method is presented for constructing exact travelling wave solutions of nonlinear partial differential equations. The main idea of this method is to take full advantage of the solutions of the elliptic equation to construct exact travelling wave solutions of nonlinear partial differential equations. More new exact travelling wave solutions are obtained for the generalized coupled Hirota–Satsuma KdV system. 相似文献