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51.
The spectral analysis of an efficient step-by-step direct integration algorithm for the structural dynamic equation is presented. The proposed algorithm is formulated in terms of two Hermitian finite difference operators of fifth-order local truncation error and it is unconditionally stable with no numerical damping presenting a fourth-order truncation error for period dispersion (global error). In addition, although it is in competition with higher-order algorithms presented in the literature, the computational effort is similar to that of the classical second-order Newmark’s method. The numerical application for nonlinear structural dynamic problems is also considered. 相似文献
52.
Asymptotic large- and short-time behavior of solutions of the linear dispersion equation μt = Uxxx in IR× IR+, and its (2k+l)th-order extensions are studied. Such a refined scattering is based on a "Hermitian" spectral theory for a pair {B,B*} of non self-adjoint rescaled operators 相似文献
53.
Changpeng PAN 《数学年刊B辑(英文版)》2021,42(4):575-582
In this paper, the author solves the Dirichlet problem for Hermitian-Poisson metric equation √?1ΛωGH = λId and proves the existence of Hermitian-Poisson metrics on flat bundles over a class of complete Hermitian manifolds. When λ = 0, the HermitianPoisson metric is a Hermitian harmonic metric. 相似文献
54.
本文研究了正定厄米特矩阵Schur补的迹和特征值的性质,通过一个不等式的证明,得到了正定厄米特矩阵和的Schur补与正定厄米特矩阵Schur补的和的迹和特征值之间的不等式. 相似文献
55.
A rank-three condition for invariant (1, 2)-symplectic almost Hermitian structures on flag manifolds
Nir Cohen Caio J.C. Negreiros Luiz A.B. San Martin 《Bulletin of the Brazilian Mathematical Society》2002,33(1):49-73
This paper considers invariant (1, 2)-symplectic almost Hermitian structures on the maximal flag manifod associated to a
complex semi-simple Lie group G. The concept of cone-free invariant almost complex structure is introduced. It involves the rank-three subgroups of G, and generalizes the cone-free property for tournaments related to 𝕊l (n,ℂ) case. It is proved that the cone-free property is necessary for an invariant almost-complex structure to take part in
an invariant (1, 2)-symplectic almost Hermitian structure. It is also sufficient if the Lie group is not B
l , l ≥ 3, G
2 or F
4. For B
l and F
4 a close condition turns out to be sufficient.
Received: 28 October 2001 相似文献
56.
We prove an existence result for topologically locally flat embeddings of 2-spheres in simply connected 4-manifolds. This topological result is deduced from a splitting theorem for pointed Hermitian modules over a cyclic group ring. A stability result for such modules is also proved. This applies to the isotopy classification of locally flat embeddings.Partially supported by the NSF. 相似文献
57.
58.
59.
Fazilet Erkekog˜lu 《Mathematical Physics, Analysis and Geometry》2006,8(4):361-388
The geometry of almost complex manifolds with degenerate indefinite Hermitian metrics is studied. 相似文献
60.
Erkki P. Liski 《应用数学学报(英文版)》1996,12(4):435-442
A new condition for the antitonicity of the inverse of Hermitian matrices with respect to the Löwner partial ordering is derived. The basic result is established by applying directly an elementary formula for a sum of matrices. 相似文献