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61.
Naoya Sumi 《Proceedings of the American Mathematical Society》1999,127(3):915-924
We show that on the 2-torus there exists a open set of regular maps such that every map belonging to is topologically mixing but is not Anosov. It was shown by Mañé that this property fails for the class of toral diffeomorphisms, but that the property does hold for the class of diffeomorphisms on the 3-torus . Recently Bonatti and Diaz proved that the second result of Mañé is also true for the class of diffeomorphisms on the -torus ().
62.
Asymptotic normality of the solutions of the initial-value problems for multidimensional Burgers' equation with weakly dependent possible non-Gaussian initial condition is proved. 相似文献
63.
赵会江 《数学物理学报(B辑英文版)》1996,(3)
FIRSTORDERQUASILINEAREQUATIONSINSEVERALINDEPENDENTVARIABLESWITHSINGULARINITIALDATAL~p(P<∞)¥(赵会江)ZhaoHuijiang(YoungScientistLa?.. 相似文献
64.
Andreas?GerndtEmail author Marc?Schirski Torsten?Kuhlen Christian?Bischof 《Journal of Mathematical Modelling and Algorithms》2005,4(1):35-52
The use of Virtual Reality (VR) techniques for the investigation of complex flow phenomena offers distinct advantages in comparison to conventional visualization techniques. Especially for unsteady flows, VR methodology provides an intuitive approach for the exploration of simulated fluid flows. However, the visualization of Computational Fluid Dynamics (CFD) data is often too time-consuming to be carried out in real-time, and thus violates essential constraints concerning real-time interaction and visualization. To overcome this obstacle, we make use of the fact that typically a multi-block approach is employed for domain decomposition, and we use the corresponding data structures for the computation of path lines and for parallelization. In this paper, we present the synthesis of fragmented multi-block data sets and our implementation of an accurate path line integration scheme in order to speed up path line computations. We report on the results of our efforts and describe a combination of this algorithm with a highly efficient visualization approach of large amounts of particle traces, thus considerably improving interactivity when exploring large scale CFD data sets.Mathematics Subject Classifications (2000) 76Mxx, 76M27, 76M28, 65M55, 65L05, 65L06, 65D05, 65Y05, 68U05. 相似文献
65.
Sujit K. Bose 《Proceedings Mathematical Sciences》2001,111(3):365-370
We consider here small flexural vibrations of an Euler-Bernoulli beam with a lumped mass at one end subject to viscous damping
force while the other end is free and the system is set to motion with initial displacementy
0(x) and initial velocityy
1 (x). By investigating the evolution of the motion by Laplace transform, it is proved (in dimensionless units of length and time)
that
, wheret
0 may be sufficiently large, provided that {y
0,y
1} satisfy very general restrictions stated in the concluding theorem. This supplies the restrictions for uniform exponential
energy decay for stabilization of the beam considered in a recent paper. 相似文献
66.
Hidefumi Ohsugi Takayuki Hibi 《Proceedings of the American Mathematical Society》2001,129(9):2541-2546
A compressed polytope is an integral convex polytope any of whose reverse lexicographic initial ideals is squarefree. A sufficient condition for a -polytope to be compressed will be presented. One of its immediate consequences is that the class of compressed -polytopes includes (i) hypersimplices, (ii) order polytopes of finite partially ordered sets, and (iii) stable polytopes of perfect graphs.
67.
Initial chain algebras on pseudotrees generalize the notion of an interval algebra on a linear order. Many relationships which hold between the various cardinal functions on interval algebras also hold for initial chain algebras. In particular, for initial chain algebras on pseudotrees, depth equals tightness, spread equals hereditary Lindelöf degree, irredundance equals the cardinality of the algebra, and incomparability equals hereditary cofinality. For interval algebras, Rubin showed that any subalgebra of regular uncountable cardinality contains either a chain of size or a pairwise incomparable family of size . This result holds for initial chain algebras as well. 相似文献
68.
This paper deals with the iterative solution of stage equations which arise when some fully implicit Runge-Kutta methods,
in particular those based on Gauss, Radau and Lobatto points, are applied to stiff ordinary differential equations. The error
behaviour in the iterates generated by Newton-type and, particularly, by single-Newton schemes which are proposed for the
solution of stage equations is studied. We consider stiff systems y'(t) = f(t,y(t)) which are dissipative with respect to
a scalar product and satisfy a condition on the relative variation of the Jacobian of f(t,y) with respect to y, similar to
the condition considered by van Dorsselaer and Spijker in [7] and [17]. We prove new convergence results for the single-Newton
iteration and derive estimates of the iteration error that are independent of the stiffness. Finally, some numerical experiments
which confirm the theoretical results are presented.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
69.
Beghin Luisa Knopova Viktoria P. Leonenko Nikolai N. Orsingher Enzo 《Journal of statistical physics》2000,99(3-4):769-781
We analyze the asymptotic behavior of the rescaled solution to the linear Korteweg–de Vries equation when the initial conditions are supposed to be random and weakly dependent. By means of the method of moments we prove the Gaussianity of the limiting process and we present its correlation function. The same technique is applied to the analysis of another third-order heat-type equation. 相似文献
70.
介绍了采用X射线光电子谱(XPS)等技术研究脉冲激光沉积在Ni、Mo、C、NaCl(100)表面的Cu、Au原子团簇的电子状态;结合Cu2p3/2 X射线光电子谱峰和Cu L3M4,5M4,5俄歇跃迁分离了电子结合能的初态和终态贡献,得出了它们随Cu表面浓度变化的关系,并对之作出了解释。使用XPS、RBS、TEM三项技术研究了Au在NaCl(100)表面的生长过程,通过计算得出了在不同表面浓度下Au原子团簇的平均高度和表面覆盖率。 相似文献