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排序方式: 共有1012条查询结果,搜索用时 15 毫秒
91.
We discuss the notion of weak transversality and clarify its role in the context of Lie group theory with several examples. In particular, we present some new results concerning models of fluid dynamics. 相似文献
92.
Trevor D. Wooley 《Compositio Mathematica》1998,111(2):149-165
Let p be a rational prime number. We refine Brauer's elementary diagonalisation argument to show that any system of r homogeneous polynomials of degree d, with rational coefficients, possesses a non-trivial p-adic solution provided only that the number of variables in this system exceeds (rd
2)2d-1. This conclusion improves on earlier results of Leep and Schmidt, and of Schmidt. The methods extend to provide analogous conclusions in field extensions of Q, and in purely imaginary extensions of Q. We also discuss lower bounds for the number of variables required to guarantee local solubility. 相似文献
93.
Using the Fourier-Laplace transform for functionals, we describe the duals of some spaces of the infinitely differentiable functions given on convex compact sets or convex domains in ?N and such that the growth of their derivatives is determined by weight sequences of a general form. 相似文献
94.
具有通用机的n组工件的排序问题 总被引:4,自引:0,他引:4
本文讨论了具有n台速度相同的专用机,一台同速度的通用机的n组工件的Cmax问题,提出了改进的LPT算法,得到了近似算法的一个估计. 相似文献
95.
D. K. Demskoi V. G. Marikhin A. G. Meshkov 《Theoretical and Mathematical Physics》2006,148(2):1034-1048
We consider two-dimensional relativistically invariant systems with a three-dimensional reducible configuration space and
a chiral-type Lagrangian that admit higher symmetries given by polynomials in derivatives up to the fifth order. Nine such
systems are known: two are Liouville-type systems, and zero-curvature representations for two others have previously been
found. We here give zero-curvature representations for the remaining five systems. We show how infinite series of conservation
laws can be derived from the established zero-curvature representations. We give the simplest higher symmetries; others can
be constructed from the conserved densities using the Hamiltonian operator. We find scalar formulations of the spectral problems.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 148, No. 2, pp. 189–205, August, 2006. 相似文献
96.
A. M. Mathai 《Annals of the Institute of Statistical Mathematics》1982,34(1):591-597
Summary Consider mutually independent inputsX
1,...,X
n onn different occasions into a dam or storage facility. The total input isY=X
1+...+X
n. This sum is a basic quantity in many types of stochastic process problems. The distribution ofY and other aspects connected withY are studied by different authors when the inputs are independently and identically distributed exponential or gamma random
variables. In this article explicit exact expressions for the density ofY are given whenX
1,...,X
n are independent gamma distributed variables with different parameters. The exact density is written as a finite sum, in terms
of zonal polynomials and in terms of confluent hypergeometric functions. Approximations whenn is large and asymptotic results are also given. 相似文献
97.
In this paper certain correspondences have been shown among various formulations of coupled-cluster theories for many electron
closed-shell systems. Specifically it is shown that (i) the energy functional using unitary ansatz of the form exp (T−T
+) is exactly sameorder by order inT with the size-consistent energy functional 〈ψ|H|ψ〉/〈ψ|ψ〉 recently obtained by us in coupled-cluster framework; (ii) in the framework of unitary ansatz of the form exp (T−T
+), both non-variational and variational approaches lead to identical equations upto any given order inT andT
+ inT∼T
2 approximation; (iii) variational procedure using our size-consistent energy functional or using the functional obtained in
the framework of unitary ansatz (as envisaged by Kutzelnigg) leads to energy in both cases, inT∼T
2 approximation, for a total of quadratic powers inT andT
+, same as Cizek’s linearised coupled pair many electron theory energy; (iv) in case of practical calculation of the energy
through the variational procedures using our size-consistent energy functional and the functional in unitary ansatz framework,
there is a loss of upper bound. 相似文献
98.
We study the limit properties of solutions to one class of systems of differential equations as the number of equations and some parameters tend to infinity. We establish a close connection between solutions to these systems and differential equations with retarded argument. Our convergence theorems provide a new method for approximation of solutions to nonlinear differential equations with retarded argument.Original Russian Text Copyright © 2005 Demidenko G. V. and Likhoshvai V. A.The authors were supported by the Russian Foundation for Basic Research (Grants 03-01-00328, 03-04-48506, 03-04-48829, 03-07-96833, 04-01-00458, 05-04-49068, and 05-07-90274), the Integration Grant of the Siberian Branch of the Russian Academy of Sciences (No. 119 and 148), the Program Development of the Scientific Potential of Higher School of the Ministry for Education of the Russian Federation (Grant 8273), and NSF:FIBR (Grant EF-0330786).__________Translated from Sibirskii Matematicheskii Zhurnal, Vol. 46, No. 3, pp. 538–552, May–June, 2005. 相似文献
99.
A formulation of the kinetic theory of dilute, classical polyatomic gases is given which parallels the Waldmann development for structureless molecules. In the first section the Boltzmann equation is written in terms of the specific rates of inelastic collision processes and then the properties of these rates and those of the corresponding collision cross sections are examined. The dependence of the distribution function on the dynamical variables is discussed and the equations of change for the gas are derived. Finally, a study is made of the properties of the linearized Boltzmann collision operation. In the second section the Boltzmann equation is deduced from a rigorous statistical-mechanical point of view and discussed in terms of the basic ideas of Bogoliubov. The computationally important special case of impulsive interactions is then considered.This research was supported in part by a grant from the National Science Foundation and in part by the Ames Laboratory of the U. S. Atomic Energy Commission. Contribution No. 2554. 相似文献
100.
为了妇科恶性肿瘤的早期诊断,对病人进行B型超声波的检查和B超评分,并把B超评分数作为初始条件,利用多组判别分析法,将它们划分为良性、过渡性或畸胎瘤和恶性等三类,是利用多元统计分析对妇科恶性肿瘤早期诊断的一种尝试. 相似文献