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81.
82.
Changjiang Bu 《Journal of Applied Mathematics and Computing》2006,22(3):255-265
Let R be a PID,chR = 2,n > 1, Mn(R) be then xn full matrix algebra over R.f denotes any invertible linear map preserving {1}-inverses from Mn(R) to itself. In this paper, we have proven thatf is an invertible linear map on Mn(R) preserving {1}-inverses if and only iff satisfies any one of the following two conditions: (i) there exists a matrixP ? GL n(R) such thatf(A) =PAP ?1 for allA ? M n(R), (ii) there exists a matrixP ? GL n(R) such thatf(A) =PA t P?1 forA ? M n(R). 相似文献
83.
Shangquan Bu 《Integral Equations and Operator Theory》2011,71(2):259-274
We study the well-posedness of the fractional differential equations with infinite delay (P
2): Da u(t)=Au(t)+òt-¥a(t-s)Au(s)ds + f(t), (0 £ t £ 2p){D^\alpha u(t)=Au(t)+\int^{t}_{-\infty}a(t-s)Au(s)ds + f(t), (0\leq t \leq2\pi)}, where A is a closed operator in a Banach space ${X, \alpha > 0, a\in {L}^1(\mathbb{R}_+)}${X, \alpha > 0, a\in {L}^1(\mathbb{R}_+)} and f is an X-valued function. Under suitable assumptions on the parameter α and the Laplace transform of a, we completely characterize the well-posedness of (P
2) on Lebesgue-Bochner spaces
Lp(\mathbbT, X){L^p(\mathbb{T}, X)} and periodic Besov spaces
B p,qs(\mathbbT, X){{B} _{p,q}^s(\mathbb{T}, X)} . 相似文献
84.
G=(V,E)表示一个顶点集为V,边集为E的有限简单无向图.若存在映射φ:V(G)→Zk(n)(Zk(n)是由{1,2,…,n}的所有k-元子集构成的集合),满足:(A) uv∈E(G),有φ(u)∩φ(u)=θ,则称φ是G的一个k-重n-顶点染色.本文证明了奇围长至少为5k-7(k=4)或5k-9(k=6)的平面图G... 相似文献
85.
Acta Mathematicae Applicatae Sinica, English Series - Joint analysis of multiple phenotypes can have better interpretation of complex diseases and increase statistical power to detect more... 相似文献
86.
Mikhail Panfilov Constantin Oltean Irina Panfilova Michel Buès 《Comptes Rendus Mecanique》2003,331(1):41-48
The quadratic law of laminar flow through porous media at high Reynolds numbers, which is well confirmed by the multiple experimental data, is shown to give rise to three fundamental paradoxes. All them can be resolved by assuming the singular structure of flow. The singularity is produced by the formation of jet brunches which invade the stagnant zones and sharply loss their kinetic energy. The numerical simulation confirms this effect. To cite this article: M. Panfilov et al., C. R. Mecanique 331 (2003). 相似文献
87.
88.
Let X be a Banach space. We show that each m : ? \ {0} → L (X ) satisfying the Mikhlin condition supx ≠0(‖m (x )‖ + ‖xm ′(x )‖) < ∞ defines a Fourier multiplier on B s p,q (?; X ) if and only if 1 < p < ∞ and X is isomorphic to a Hilbert space; each bounded measurable function m : ? → L (X ) having a uniformly bounded variation on dyadic intervals defines a Fourier multiplier on B s p,q (?; X ) if and only if 1 < p < ∞ and X is a UMD space. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
89.
Towards auction algorithms for large dense assignment problems 总被引:1,自引:0,他引:1
In this paper, we focus on the problem of solving large-scale instances of the linear sum assignment problem by auction algorithms.
We introduce a modified auction algorithm, called look-back auction algorithm, which extends the forward auction algorithm
by the ability of reusing information from previous bids. We show that it is able to reuse information from the previous bids
with high efficiency for all tested types of input instances. We discuss then the design and implementation of a suite of
sequential and distributed memory auction algorithms on a Linux cluster with the evaluation on several types of input instances
of the linear sum assignment problem. Our results show that the look-back auction algorithm solves sequentially nearly all
types of dense instances faster than other evaluated algorithms and it is more stable than the forward-reverse auction algorithm
for sparse instances. Our distributed memory auction algorithms are fully memory scalable.
This research has been supported by IGA CTU under grant CTU0308013 and under research program MSMT 6840770014. 相似文献
90.