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991.
R. Cheikh J. Hanssen B. Joulakian 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,2(3):203-208
The fivefold differential cross section (5DCS) of the ionisation by electron impact of atomic sodium is determined theoretically
for its fundamental 3s(2
S) state and the excited 3p(2
P) and 3d(2
D) states by a procedure which employs in the transition matrix element of the first order Born approximation, the correlated
double continuum (3C) wave function. This permits us to determine the statistical M-state population and the orientation and alignment tensors in (e,2e) detection. It is also shown that, the use of Gamow correlation term, in the independent particle (2C) model, reproduces,
only in some situations, the shape of the angular distribution of the 5DCS obtained by the (3C) wave function.
Received: 17 November 1997 / Received in final form: 16 March 1998 / Accepted: 21 March 1998 相似文献
992.
We study two indeterminate Hamburger moment problems and the corresponding orthogonal polynomials. The coefficients in their
recurrence relations are of exponential growth or are polynomials of degree 2. The entire functions in the Nevanlinna parametrization
are found. The orthogonal polynomials with polynomial recurrence coefficients resemble the Freud polynomials with a = 1/2 . Inequalities are given for the largest zero and the asymptotic behavior of the largest zero is established.
April 24, 1996. Date revised: March 3, 1997. 相似文献
993.
N. G. Medhin 《Journal of Optimization Theory and Applications》1993,79(1):87-103
In this paper, we characterize optimal pairs for a hereditary control problem where the state is constrained. We use relaxed controls and the technique of penalization.This research was supported by NSF Grant No. HRD-91-54077. 相似文献
994.
为改造正线性算子以提高其逼近阶,本文利用有限振荡核方法,从常见的Fejer算子出发,构造出一种莼性多项式算子Ln^(m)(f;x),称F-B算子,它的表达式具有良好的递推性能;通过对其收敛性和饱和性的讨论,证得F-B算子对充分光滑函数的逼近阶可达O(1/n^2m+1),优于Butzer与Stark的结果(O(1/n^4)),并包含Baskakov的结果(O(1/n^3)与O(1/n^5))为其特例 相似文献
995.
D. Han 《Applied Mathematics and Optimization》2002,45(1):63-74
The alternating direction method is an attractive method for solving large-scale variational inequality problems whenever
the subproblems can be solved efficiently. However, the subproblems are still variational inequality problems, which are as
structurally difficult to solve as the original one. To overcome this disadvantage, in this paper we propose a new alternating
direction method for solving a class of nonlinear monotone variational inequality problems. In each iteration the method just
makes an orthogonal projection to a simple set and some function evaluations. We report some preliminary computational results
to illustrate the efficiency of the method.
Accepted 4 May 2001. Online publication 19 October, 2001. 相似文献
996.
SONGTong-Qiang FANHong-Yi 《理论物理通讯》2002,37(5):593-596
Using non-Hermitian realizations of SU(1,1) Lie algebra in terms of an f-oscillator,we generalize the notion of nonlinear coherent states to the single-mode and two-mode nonlinear SU(1,1) coherent states.Taking the nonlinearity function f(k)=Lk^1(η^2)[(k 1)Lk^0(η^2)]^-1,their statistical properties are studied. 相似文献
997.
This paper offers an analysis on a standard long-step primal-dual interior-point method for nonlinear monotone variational inequality problems. The method has polynomial-time complexity and its q-order of convergence is two. The results are proved under mild assumptions. In particular, new conditions on the invariance of the rank and range space of certain matrices are employed, rather than restrictive assumptions like nondegeneracy. 相似文献
998.
On interpolation with products of positive definite functions 总被引:1,自引:0,他引:1
Hans Strauss 《Numerical Algorithms》1997,15(2):153-165
In this paper we consider the problem of scattered data interpolation for multivariate functions. In order to solve this problem, linear combinations of products of positive definite kernel functions are used. The theory of reproducing kernels is applied. In particular, it follows from this theory that the interpolating functions are solutions of some varational problems. 相似文献
999.
M. -B. A. Babaev 《Mathematical Notes》1997,62(1):15-29
We study the approximation of functions of several variables by bilinear forms that are the pairwise products of functions
of fewer variables. The order of approximation of Sobolev classesW
q
r
by bilinear forms inL
p
for 2≤q≤p≤∞ is found.
Translated by N. K. Kulman
Translated fromMatematicheskie Zametki, Vol. 62, No. 1, pp. 18–34, July, 1997. 相似文献
1000.
In this paper, we compare two methods for obtaining solutions for free problems in the calculus of variations. The first is due to Carathéodory (Ref. 1) and the second due to Leitmann (Ref. 2). Both methods introduce the notion of equivalent variational problems. Using either approach, an auxiliary problem is obtained for which the solution is more easily obtained. We compare both approaches by using each to solve the same class of examples. We conclude our discussion by unifying the two approaches into one and illustrating the potential of this new method through the use of an elementary example. 相似文献