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91.
Fang Jie 《数学学报(英文版)》1996,12(3):249-253
In this paper we introduce an algebraic concept of the product of Ockham algebras called the Braided product. We show that ifL
i
MS(i=1, 2, ,n) then the Braided product ofL
i(i=1, 2, ,n) exists if and only ifL
1, ,L
n have isomorphic skeletons. 相似文献
92.
Janusz Grabowski 《Annals of Global Analysis and Geometry》1993,11(3):213-220
It is proved that for infinite dimensional Lie groups in the sense of the differential calculus of Frölicher and Kriegl the derivative of the exponential mappings is given by the formula d(exp)(X)Y=dexp(X)(e)
0
1
Adexp(–tX)
Y dt, where stands for the left translation ande is the neutral element.This work was supported by the Alexander von Humboldt-Stiftung. 相似文献
93.
94.
95.
In this paper, we examine three algorithms in the ABS family and consider their storage requirements on sparse band systems. It is shown that, when using the implicit Cholesky algorithm on a band matrix with band width 2q+1, onlyq additional vectors are required. Indeed, for any matrix with upper band widthq, onlyq additional vectors are needed. More generally, ifa
kj
0,j>k, then thejth row ofH
i
is effectively nonzero ifj>i>k. The arithmetic operations involved in solving a band matrix by this method are dominated by (1/2)n
2
q. Special results are obtained forq-band tridiagonal matrices and cyclic band matrices.The implicit Cholesky algorithm may require pivoting if the matrixA does not possess positive-definite principal minors, so two further algorithms were considered that do not require this property. When using the implicit QR algorithm, a matrix with band widthq needs at most 2q additional vectors. Similar results forq-band tridiagonal matrices and cyclic band matrices are obtained.For the symmetric Huang algorithm, a matrix with band widthq requiresq–1 additional vectors. The storage required forq-band tridiagonal matrices and cyclic band matrices are again analyzed.This work was undertaken during the visit of Dr. J. Abaffy to Hatfield Polytechnic, sponsored by SERC Grant No. GR/E-07760. 相似文献
96.
J. B. Lasserre 《Journal of Optimization Theory and Applications》1991,70(3):583-595
We consider two-dimensional discrete-time linear systems with constrained controls. We propose a simple polynomial time procedure to give an exact external representation of theN-step reachable set and controllable set. The bounding hyperplanes are explicitly derived in terms of the data of the problem. By using a result in computational geometry, all the calculations are made in polynomial time in contrast to classical methods. The limit case asN is also investigated. 相似文献
97.
Vera V. Kovacevic-Vujcic 《Mathematical Programming》1991,52(1-3):467-479
This paper proposes a procedure for improving the rate of convergence of interior point methods for linear programming. If (x
k
) is the sequence generated by an interior point method, the procedure derives an auxiliary sequence (
). Under the suitable assumptions it is shown that the sequence (
) converges superlinearly faster to the solution than (x
k
). Application of the procedure to the projective and afflne scaling algorithms is discussed and some computational illustration is provided. 相似文献
98.
David Fryberger 《Foundations of Physics Letters》1991,4(5):459-464
The Coulomb scattering of an electron by a magnetic monopole is analyzed using a lowest-order quantum perturbation approximation suggested by a two-potential Lagrangian form for classical electromagnetism, generalized through the use of spacetime algebra to include magnetic monopoles. Good agreement with existing conventional analyses of this problem is demonstrated.1. Work supported by Department of Energy contract DE-AC03-76SF00515.2. The idea to employ spacetime algebra (sometimes called Dirac algebra) to incorporate magnetic monopoles into classical electromagnetic theory was proposed by de Faria-Rosaet al. [3].3. This is a factori difference between the definition of 5 by Eq. (3) and that by Bjorken and Drell [6]. Since a cross section (without interference terms) is being calculated, we can ignore this distinction. 相似文献
99.
利用算符代数中的分析方法,得到了多模海森堡(Heisenberg)代数中的BCH公式和压缩算符的展开式。 相似文献
100.
通常,人们认为Kiyoshi Iséki在20世纪60年代引入的BCI-代数是组合逻辑中BCI逻辑的代数对等物。然而这种广为人知的断言却是有问题的,因为BCI逻辑关于BCI代数是不完备的。在本文中,我们引入一种称为MPE的偏序代数。在MPE中的每个不等式对应BCI逻辑中的一个重言式且反之亦然,从而MPE代数是与BCI逻辑完备的代数类。 相似文献