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991.
In this paper, we establish the generalized symmetric SOR method (GSSOR) for solving the large sparse augmented systems of linear equations, which is the extension of the SSOR iteration method. The convergence of the GSSOR method for augmented systems is studied. Numerical resume shows that this method is effective. 相似文献
992.
For a symmetric sign pattern S1 the inertia set of S is defined to be the set of all ordered triples si(S) = {i(A) : A = A^T ∈ Q(S)} Consider the n × n sign pattern Sn, where Sn is the pattern with zero entry (i,j) for 1 ≤ i = j ≤ n or|i -j|=n- 1 and positive entry otherwise. In this paper, it is proved that si(Sn) = {(n1, n2, n - n1 - n2)|n1≥ 1 and n2 ≥ 2} for n ≥ 4. 相似文献
993.
Sungwook Lee 《Differential Geometry and its Applications》2008,26(5):536-543
A generalized integral representation formula for spacelike maximal surfaces in a certain 3-dimensional homogeneous spacetime is obtained. This spacetime has a solvable Lie group structure with left invariant metric. The normal Gauß map of maximal surfaces in the homogeneous spacetime is discussed and the harmonicity of the normal Gauß map is studied. 相似文献
994.
We deal with the Kreîn-Langer problem for
-valued functions on the band (–2a, 2a)×, where
is the algebra of continuous linear operators on a Hilbert space
,a a finite positive number and a topological Abelian group. We show that every weakly continuous -indefinite function
admits a strongly continuous -indefinite continuation to × with the same indefiniteness index . We give a parametrization of the extensions in terms of operator-valued Schur functions. 相似文献
995.
Ana Duff 《Journal of Pure and Applied Algebra》2003,184(1):59-76
In this paper we describe the invariant forms of toral K-graded Lie superalgebras and, in particular, of the elementary unitary Lie superalgebra over a superring K containing . 相似文献
996.
Alfio?BorzìEmail author Georg?Propst 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2003,54(6):1050-1072
The Liebau phenomenon is the occurrence of valveless
pumping through the application of a periodic force at a place
which lies asymmetric with respect to system configuration. This
paper is concerned with two different physical configurations and
respective models. Comparison and derivation among the models is
discussed. Accurate numerical schemes which solve these models are
presented. By means of numerical simulations it is investigated
under which conditions valveless pumping takes place. 相似文献
997.
Canonical angles between subspaces of a unitary space are characterized
by a min-max property which involves inner products. 相似文献
998.
999.
Let G be a connected graph. We denote by σ(G,x) and δ(G) respectively the σ-polynomial and the edge-density of G, where
. If σ(G,x) has at least an unreal root, then G is said to be a σ-unreal graph. Let δ(n) be the minimum edgedensity over all n vertices graphs with σ-unreal roots. In this paper, by using the theory of adjoint polynomials, a negative answer to a problem posed by Brenti et
al. is given and the following results are obtained: For any positive integer a and rational number 0≤c≤1, there exists at least a graph sequence {G
i}1≤i≤a
such that G
i is σ-unreal and δ(G
i)→c as n→∞ for all 1 ≤i≤a, and moreover, δ(n)→0 as n→∞.
Supported by the National Natural Science Foundation of China (10061003) and the Science Foundation of the State Education
Ministry of China. 相似文献
1000.
This paper offers characterizations of subsolutions of the heat equation
(the subcaloric functions) and the infinity heat
equation
(the infinity-subcaloric functions) by
means of comparison properties with explicit families of solutions of
the corresponding equations. The primary ingredients of functions in
these families are translates of solutions which depend radially on the
space variables. Results of independent interest include the
presentation and study of the class of infinity-caloric functions
employed in the characterization. 相似文献