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151.
Within the concept of projective lattice geometry we are considering the class of stable geometries which have also been introduced in [14]. The investigation of their basic properties will result in fundamental structure theorems which especially give a lattice-geometric characterization of free left modules of rank 6 over proper right Bezout rings of stable rank 2. This yields a proper generalization of previous results of ours. 相似文献
152.
Ignacio Bajo 《Monatshefte für Mathematik》1994,118(1-2):1-6
Let
be a complex Lie algebra,
its underlying real Lie algebra,
a real form of
and ·, · the euclidean product induced by the real part of an hermitian inner product on
. Let aut
be the Lie algebra of skew-symmetric derivations of
. We give necessary and sufficient conditions to ensure that aut
is composed of skew-hermitian derivations. As an application, we study holomorphy in large subgroups of isometries of Lie groups. 相似文献
153.
The Boussinesq approximation, where the viscosity depends polynomially on the shear rate, finds more and more frequent use in geological practice. In the paper, this modified Boussinesq approximation is investigated as a dynamical system for which the existence of a global attractor is proved. Finally, a new criterion for estimating the fractal dimension of invariant sets is formulated and its application to the problem under consideration is illustrated. 相似文献
154.
We study hölder regularity of minimizers of the functional
, wherep(x) takes only two values and jumps across a Lipschitz surface. No restriction on the two values is imposed.This article was processed by the author using the Springer-Verlag TEX PJourlg macro package 1991. 相似文献
155.
Christian Sunyach 《Potential Analysis》1994,3(2):171-187
Résumé Dans cet article j'étudie le comportement à l'infini des potentiels des chaînes de Markov sur
d
(d3) proches du mouvement brownien, tout spécialement le cas des marches aléatoires, ainsi que des critères de transience et de récurrence inspirés de la méthode utilisée.
We study the asymptotic behaviour of potentials of Markov chains on d (d3), closed to Brownian motion, and particularly the case of random walks. Following a similar approach, we give transience and recurrence criteria.相似文献
156.
D. Leladze 《Georgian Mathematical Journal》1994,1(3):287-302
We have obtained an estimate, in terms of partial and mixed moduli, of the continuity of deviation of the Cesáro (C, ) means ( = (1,...,n),i , 1 > –1,
) of the sequence of rectangular partial sums ofn-multiple (n>1) conjugate trigonometric series from then-multiple truncated conjugate function. This estimate implies the result on them
-convergence (1) of (C, ) means (1 > 0,
) provided that the essential conditions are imposed on the partial moduli of continuity. Finally, it is shown that them
-convergence cannot be replaced by ordinary convergence. 相似文献
157.
David Cruz-Uribe 《Integral Equations and Operator Theory》1994,20(2):231-237
In this note I give necessary and sufficient conditions on outer functionsf andg for the operator
to be bounded and invertible on H2. I also discuss the relationship of this question to two open questions in operator theory and weighted norm inequalities. 相似文献
158.
Ruey-Jen Jang-Lewis Harold Dean Victory Jr. 《Integral Equations and Operator Theory》1994,18(1):88-108
LetE be a Banach lattice having order continuous norm. Suppose, moreover,T is a nonnegative reducible operator having a compact iterate and which mapsE into itself. The purpose of this work is to extend the previous results of the authors, concerning nonnegative solvability of (kernel) operator equations on generalL
p-spaces. In particular, we provide necessary and sufficient conditions for the operator equation x=T
x+y to possess a nonnegative solutionxE wherey is a given nonnegative and nontrivial element ofE and is any given positive parameter. 相似文献
159.
D. B. Uglov 《Letters in Mathematical Physics》1994,31(1):65-76
It is shown that the Lie algebra of the automorphic, meromorphic sl(2, )-valued functions on a torus is a geometric realization of a certain infinite-dimensional finitely generated Lie algebra. In the trigonometric limit, when the modular parameter of the torus goes to zero, the former Lie algebra goes over into the sl(2, )-valued loop algebra, while the latter goes into the Lie algebra (A
1
(1)
)/(centre). 相似文献
160.
Uwe Grimm 《Letters in Mathematical Physics》1994,32(3):183-187
Explicit expressions for three series ofR matrices which are related to a dilute generalisation of the Birman-Wenzl-Murakami algebra are presented. Of those, one series is equivalent to the quantumR matrices of theD
n+1
(2)
generalised Toda systems, whereas the remaining two series appear to be new. 相似文献