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61.
视频编码中的块运动估计算法 总被引:7,自引:0,他引:7
在视频压缩的一些国际标准,如H.261,H.263,MPEG0-1,MPEG-2,HDTV中,视频系统编码器的复杂性最主要取决于运动估计。下文以MPEG-2编码器为例,通过计算机模拟实验,得出了一些常用运动估计算法的对比实验结果,以及采用常用的几种匹配函数的对比实验结果。 相似文献
62.
The adsorption behavior (capacity, density distribution and packing density) and the isosteric heat versus loading in a slit pore whose walls contain defective graphene layers are investigated in this paper. The defective wall is characterized by the extent and size of the defect. Simulation results obtained with the Grand Canonical Monte Carlo method reveal complex patterns of isosteric heat, and this complex behavior is a result of the interplay between three factors: (i) the surface heterogeneity (solid-fluid interaction, sites with varying degree of affinity), (ii) fluid-fluid interaction and (iii) the overlapping of potentials exerted by the two defective walls. We illustrate this with argon adsorption in pores of various sizes, and results obtained from the simulation agree qualitatively with the experimental data at 77 K on Saran microporous S600H and micro-mesoporous S84 charcoals of Beebe et al. [R.A. Beebe, B. Millard, J. Cynarski, J. Am. Chem. Soc. 75 (1953) 839]. The S600H was found to contain pores predominantly in the neighborhood of 7 Å with 30% of defect and a defective size of 2.84 Å. This is consistent with the argument made by Beebe et al. that this sample is a microporous solid and most pores can accommodate only one layer. The other sample, S84, has larger pores than S600H, and it is found that it has a wider pore size distribution and the pore width is centered at about 12 Å. 相似文献
63.
The HERA - B Collaboration I. Abt et al. 《The European Physical Journal C - Particles and Fields》2003,26(3):345-355
Using the HERA - B detector, the production cross section has been measured in 920 GeV proton collisions on carbon and titanium targets. The production was tagged via inclusive bottom quark decays into by exploiting the longitudinal separation of decay vertices from the primary proton-nucleus interaction. Both e
+
e
-
and channels have been reconstructed and the combined analysis yields the cross section .
Received: 6 June 2002 / Revised version: 2 September 2002 / Published online: 8 November 2002 相似文献
64.
Victor V. Dodonov Margarita A. Man’ko Vladimir I. Man’ko Apostol Vourdas 《Journal of Russian Laser Research》2007,28(5):404-428
A brief review of the history of ten workshops/conferences on “Squeezed States and Uncertainty Relations” and main achievements
in the related fields of quantum physics for the period from 1991 to 2007 are presented. 相似文献
65.
66.
S. A. Andronati A. A. Krys’ko B. M. Chugunov T. A. Kabanova A. G. Artemenko 《Russian Journal of Organic Chemistry》2006,42(8):1174-1182
A new series of RGDF mimetics, derivatives of 4-(isoindolin-5-yl)amino-4-oxobutanoic acid, was synthesized. The compounds obtained inhibit efficiently the thrombocytes aggregation in experiments in vitro; their biological targets are fibrinogen receptors. The antiaggregatory activity and the affinity correlate with the hydrophobicity of the compounds. 相似文献
67.
Role of readily hydrolyzable polysaccharides of larch wood in production of board materials is studied. 相似文献
68.
Reactions between polypyromellitamido acid and component materials of microelectronic articles were examined by thermogravimetric analysis. Modes of modification of the surfaces of semiconductor structures to be used in formation of a system of interconnections with polyimide as interlayer insulator to obtain a high adhesion between the layers via their chemical reactions. 相似文献
69.
We consider a multiperiod mean-variance model where the model parameters change according to a stochastic market. The mean
vector and covariance matrix of the random returns of risky assets all depend on the state of the market during any period
where the market process is assumed to follow a Markov chain. Dynamic programming is used to solve an auxiliary problem which,
in turn, gives the efficient frontier of the mean-variance formulation. An explicit expression is obtained for the efficient
frontier and an illustrative example is given to demonstrate the application of the procedure. 相似文献
70.
A fully coupled formulation combining reactive transport and an existing thermo-hydro-mechanical (THM) code is presented.
Special attention has been given to phenomena likely to be encountered in clay barriers used as part of containment systems
of nuclear waste. The types of processes considered include hydrolysis, complex formation, oxidation/reduction reactions,
acid/base reactions, precipitation/dissolution of minerals and cation exchange. Both kinetically-controlled and equilibrium-controlled
reactions have been incorporated. The total analytical concentrations (including precipitated minerals) are adopted as basic
transport variables and chemical equilibrium is achieved by minimizing Gibbs Free Energy. The formulation has been incorporated
in a general purpose computer code capable of performing numerical analysis of engineering problems. A validation exercise
concerning a laboratory experiment involving the heating and hydration of an expansive compacted clay is described. 相似文献