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141.
Based on the property analysis of interferential multispectral images, a novel compression algorithm of partial set partitioning in hierarchical trees (SPIHT) with classified weighted rate-distortion optimization is presented.After wavelet decomposition, partial SPIHT is applied to each zero tree independently by adaptively selecting one of three coding modes according to the probability of the significant coefficients in each bitplane.Meanwhile the interferential multispectral image is partitioned into two kinds of regions in terms of luminous intensity, and the rate-distortion slopes of zero trees are then lifted with classified weights according to their distortion contribution to the constructed spectrum.Finally a global ratedistortion optimization truncation is performed.Compared with the conventional methods, the proposed algorithm not only improves the performance in spatial domain but also reduces the distortion in spectral domain. 相似文献
142.
Closely packed dense frequency selective surface 总被引:1,自引:0,他引:1
In order to realize wideband filtering properties of frequency selective surface (FSS), FSS of closely packed elements is presented. The Y loop elements are chosen as the graphics elements. Based on the spectral domain method, the frequency response is analyzed for different incident angles and polarizations. The result of the numerical analysis shows that the dense FSS has wide passband with better independence of angle and polarization. 相似文献
143.
Banach空间中全纯映射的若干性质 总被引:20,自引:0,他引:20
本文将全纯映射的若干性质推广到Banach空间,并应用这些性质研究有界域中的凸映射与星形映射. 相似文献
144.
We consider a kinetic BGK model relaxing to isentropic gas dynamics previously introduced by the authors, but with Dirichlet boundary condition on the incoming velocities. We pass to the limit as the relaxation parameter tends to zero by compensated compactness inside the domain, and obtain that the limit satisfies entropy inequalities on the boundary involving weak traces of entropy fluxes. Our method is very general and could be applied to any entropy satisfying BGK model as soon as we have strong compactness of the macroscopic variables inside the domain. 相似文献
145.
In this article, we study the homogenization of the family of parabolic equations over periodically perforated domains
. Here, Ωɛ=ΩS
ɛ is a periodically perforated domain. We obtain the homogenized equation and corrector results. The homogenization of the
equations on a fixed domain was studied by the authors [15]. The homogenization for a fixed domain and
has been done by Jian [11]. 相似文献
146.
This paper discusses the spectral properties and numerical simulation for the second order elliptic operators with rapidly
oscillating coefficients in the domains which may contain small cavities distributed periodically with period ε. A multiscale
asymptotic analysis formula for this problem is obtained by constructing properly the boundary layer. Finally, numerical results
are given, which provide a strong support for the analytical estimates 相似文献
147.
In the cases of soft magnetic materials or complex domain configurations, investigations of the domain structure by the conventional Bitter pattern technique are generally difficult. It is demonstrated in this paper, referring to the examples of domain images of thin permalloy films and the basal surface of bulk cobalt single crystals, that this problem can be overcome by the application of digital image processing (DIP) system. In particular, the visibility limit in domain observation was expanded by an order of magnitude and high quality domain images could be obtained. Improvements over earlier results were achieved. 相似文献
148.
In the last decades it was observed that Clifford algebras and geometric product provide a model for different physical phenomena. We propose an explanation of this observation based on the theory of bounded symmetric domains and the algebraic structure associated with them. The invariance of physical laws is a result of symmetry of the physical world that is often expressed by the symmetry of the state space for the system implying that this state space is a symmetric domain. For example, the ball of all possible velocities is a bounded symmetric domain. The symmetry on this ball follow from the symmetry of the space-time transformations between two inertial systems, which fixes the so-called symmetric velocity between them. The Lorenz transformations acts on the ball Sof symmetric velocities by conformal transformations. The ball Sis a spin ball (type IV in Cartan's classification). The Lie algebra of this ball is defined a triple product that is closely related to geometric product. The relativistic dynamic equations in mechanics and for the Lorenz force is described by this Lie algebra and the triple product. 相似文献
149.
提出一种交互式自动挖掘知识的模型,论述了该模型的原理、实现机制,并讨论了模型中数据宝藏和影响域及其相互关系.该模型同时具有在线性与深入挖掘的优点,能灵活有效地满足实际应用的需求. 相似文献
150.
Bruce Olberding 《Proceedings of the American Mathematical Society》1999,127(7):1917-1921
A weakened version of the Jordan-Hölder theorem is shown to hold for torsion-free finite rank modules over an integral domain precisely when is a Prüfer domain.