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101.
Khalfa Douak 《Journal of Computational and Applied Mathematics》1996,70(2):279-295
We are dealing with the concept of d-dimensional orthogonal (abbreviated d-orthogonal) polynomials, that is to say polynomials verifying one standard recurrence relation of order d + 1. Among the d-orthogonal polynomials one singles out the natural generalizations of certain classical orthogonal polynomials. In particular, we are concerned, in the present paper, with the solution of the following problem (P): Find all polynomial sequences which are at the same time Appell polynomials and d-orthogonal. The resulting polynomials are a natural extension of the Hermite polynomials.
A sequence of these polynomials is obtained. All the elements of its (d + 1)-order recurrence are explicitly determined. A generating function, a (d + 1)-order differential equation satisfied by each polynomial and a characterization of this sequence through a vectorial functional equation are also given. Among such polynomials one singles out the d-symmetrical ones (Definition 1.7) which are the d-orthogonal polynomials analogous to the Hermite classical ones. When d = 1 (ordinary orthogonality), we meet again the classical orthogonal polynomials of Hermite. 相似文献
102.
运用包络半群的理论,对接近关系中一个重要定理给出了一个简单证明.作为这一定理的应用,我们得到接近关系可乘性的一个结果.并且对另一种接近关系,也得到一个结果.这两个定理减弱了Clay在这一领域中两个定理的条件. 相似文献
103.
104.
We show that the restricted star-triangle relation introduced by Bazhanov and Baxter can be obtained either from the star-triangle relation of the chiral Potts model or from the star-square relation proposed by Kashaev, Mangazeev, and Stroganov, and give a response to a guess of Bazhanov and Baxter. 相似文献
105.
E. M. Kovyazina 《Mathematical Notes》1996,60(6):666-670
It is proved that a τ-adic relation characterizing a Butler group is piecewise rational.
Translated fromMatematicheskie Zametki, Vol. 60, No. 6, pp. 882–887, December, 1996. 相似文献
106.
Key words The rheological properties of rat arteries were studied in vitro. Using intact arterial segments undergoing large deformations in longitudinal and circumferential direction, both the stress-strain relationship and the corresponding histological changes with deformation are presented. Correlations between the mechanical properties and the histological structure are discussed. 相似文献
107.
TENG Honghui & JIANG Zonglin . Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sci- ences Beijing China . Graduate University of Chinese Academy of Sciences Beijing China 《中国科学G辑(英文版)》2005,48(6):739-749
Shock wave focusing is a fundamental problem in the shock wave research and the instantaneous impulse of high temperature and pressure generated at the focal points has been applied recently in industrial and medical researches[1]. There are several methods to create shock wave focusing, among which the more commonly-used one is to make a planar shock wave reflect from a concave surface, such as the elliptical or parabolic re- flector. Toroidal shock wave focusing has been proposed and investi… 相似文献
108.
In this paper we rigorously establish the existence of the mobility coefficient for a tagged particle in a simple symmetric exclusion process with adsorption/desorption of particles, in a presence of an external force field interacting with the particle. The proof is obtained using a perturbative argument. In addition, we show that, for a constant external field, the mobility of a particle equals to the self-diffusivity coefficient, the so-called Einstein relation. The method can be applied to any system where the environment has a Markovian evolution with a fast convergence to equilibrium (spectral gap property). In this context we find a necessary relation between forward and backward velocity for the validity of the Einstein relation. This relation is always satisfied by reversible systems. We provide an example of a non-reversible system, where the Einstein relation is valid.This revised version was published online in March 2005 with corrections to the page numbers. 相似文献
109.
本文就乌鲁木齐市不同民族,不同职业的居民对保险产品的认同水平运用χ2统计量[1]及关系矩阵进行齐一性假设检验,并对结果进行分析,得出了合乎情理的结论。根据居民职业的不同我们可以将文卫科、企管、工人、农牧、服务业、其他职业归为一类,而"公务员"、"金融"、"个体"各为一类。不同民族的居民对保险的认同水平同样差异显著:回族、维族与其它民族的差异性很小;回族与汉族有差异不大;而维族与汉族之间差异最大。 相似文献
110.
文章介绍了我国生物学家汤佩松先生和理论物理学家王竹溪先生42年前在植物生理学方面作出的一项具有重要历史意义的贡献.他们于1941年先于西方科学家二十多年提出解释植物细胞水分关系的热力学理论,首先引入了水势概念.然而这项贡献一直被埋没四十多年才得到承认.文章分析了汤佩松和王竹溪先生工作的内容、历史地位及其产生的背景,讨论了其在国内外的遭遇的原因及今日应当从中记取的教训. 相似文献