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991.
Jiansong Zhang Danping Yang Hongfei Fu Hui Guo 《Numerical Linear Algebra with Applications》2011,18(4):695-705
Based on the overlapping‐domain decomposition and parallel subspace correction method, a new parallel algorithm is established for solving time‐dependent convection–diffusion problem with characteristic finite element scheme. The algorithm is fully parallel. We analyze the convergence of this algorithm, and study the dependence of the convergent rate on the spacial mesh size, time increment, iteration times and sub‐domains overlapping degree. Both theoretical analysis and numerical results suggest that only one or two iterations are needed to reach to optimal accuracy at each time step. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
992.
In this paper, we show the following result: Let K
i
be a knot in a closed orientable 3-manifold M
i
such that (M
i
,K
i
) is not homeomorphic to (S
2 ×S
1, x
0 ×S
1), i = 1, 2. Suppose that the Euler Characteristic of any meridional essential surface in each knot complement E(K
i
) is less than the difference of one and twice of the tunnel number of K
i
. Then the tunnel number of their connected sum will not go down. If in addition that the distance of any minimal Heegaard
splitting of each knot complement is strictly more than 2, then the tunnel number of their connected sum is super additive. 相似文献
993.
We investigate the Morita context and graded cases for weak group corings and derive some equivalent conditions for μ to be
surjective. Furthermore, we develop Galois theory for weak group corings. As an application, we give Galois theory for comodulelike
algebras over a weak Hopf group coalgebra. 相似文献
994.
We give new generalizations of some q-series identities of Dilcher and Prodinger related to divisor functions. Some interesting special cases are also deduced,
including an identity related to overpartitions studied by Corteel and Lovejoy. 相似文献
995.
In this paper,we characterize all generalized low pass filters and MRA Parseval frame wavelets in L 2 (R n ) with matrix dilations of the form (Df)(x) =√ 2f(Ax),where A is an arbitrary expanding n × n matrix with integer coefficients,such that |det A| = 2.We study the pseudo-scaling functions,generalized low pass filters and MRA Parseval frame wavelets and give some important characterizations about them.Furthermore,we give a characterization of the semiorthogonal MRA Parseval frame wavelets and provide several examples to verify our results. 相似文献
996.
In this work, characteristics of microcavity top-emitting red organic light-emitting device (TEROLED) having metallic electrodes had been examined. The TEOLED shows the higher efficiency in comparison with that of the bottom OLED. However, color variation with the increasing view angles is also observed. For the purpose of diminishing the blue-shift of resonant wavelength (RW) in the device with increasing view angle, the effect of out-coupling layer on the emission properties of the TEOLED is discussed in detail. Finally, the out-coupling layer was introduced in theory without sacrificing the efficiency through precise optical simulation. 相似文献
997.
Ruipeng Guo 《Optik》2011,122(21):1890-1894
An experimental investigation of a modified Beckmann-Kirchhoff scattering theory applied in an in-process optical measurement of surface quality is described. The proposed theory describes the scattered light intensity distribution from a surface with the additional layers, and can be employed to analyze the surface characteristics in in-process measurement. Based on light scattering principle and machine vision method, the surface roughness is extracted to testify the correction of the modified Beckmann-Kirchhoff scattering theory. The experimental apparatus consists of a collimated laser diode, a beam splitter, a screen, a measuring lens and a camera. Test specimens with different surface roughness are studied. The results obtained demonstrate the feasibility of in-process optical measurement of surface quality using the modified model. 相似文献
998.
Ag-mediated charge transfer from electron-doped SrTiO3 to molecules CO and NO has been studied through the first-principles calculations based on density functional theory (DFT). Evaluation of Fukui functions indicates that Ag atom on SrTiO3 (001) surface is presented as an active reduction and oxidation site. It shows that Ag prefers to mediate the charge transfer from electronically excited SrTiO3 to target species. It illustrates that electron initially transfers from electron-doped SrTiO3 to Ag, i.e., Ag is negatively charged. Interfacial charge transfer induces dipole moment and changes the surface work function. SrO-termination of SrTiO3 (001) surface has weak activity to CO and NO while CO and NO can be strongly adsorbed on the negatively charged Ag atom. Negatively charged Ag donates its charge to the molecules. Charge occupies the molecule π2p* orbital, which is responsible for the activation of the molecular bonds. Evidence that deposited metals on photocatalyst surface can efficiently separate the photogenerated electron-hole pairs has been addressed in this study. 相似文献
999.
Li Liu Zihao Zhou Qinlin Guo Zhen Yan Yunxi Yao D. Wayne Goodman 《Surface science》2011,605(17-18):L47-L50
The growth and morphology of two-dimensional (2-D) gold islands on a single-layer graphene supported on Ru(0001) have been studied by scanning tunneling microscopy (STM). Our findings show that gold exhibits 2-D structures up to a gold dosage of 0.75 equivalent monolayers, and that these 2-D gold islands are thermally stable at room temperature. Parallel polarization modulation infrared reflection absorption spectroscopic (PM-IRAS) and high resolution electron energy loss spectroscopic (HREELS) studies indicate that carbon monoxide (CO) adsorbs on these 2-D gold islands at 85 K, showing a characteristic CO stretching feature at 2095 cm? 1 for a saturation coverage of CO. The red shift of the CO stretching frequency compared to that on charge neutral gold is consistent with electron transfer from graphene to gold, i.e., an electron-rich gold overlayer. Preliminary data obtained by dosing molecular oxygen onto this CO pre-covered surface suggest that the 2-D gold islands catalyze the oxidation of CO. 相似文献
1000.
Zhenghong He Zhicheng Ye Qingyu Cui Jiliang Zhu Hongyue Gao Yuye Ling Hongqing Cui Jiangang Lu Xiaojun Guo Yikai Su 《Optics Communications》2011,284(16-17):4022-4027
We study one-dimensional photonic crystals made of cholesteric liquid crystals with sandwiched isotropic defect layers. Based on the Berreman Fast 4 × 4 matrix method, the dispersion relation of one-dimensional photonic crystals is calculated and the corresponding reflection chromaticity is obtained. It is found that the color shift could be controlled by adjusting the thickness and refractive index of the isotropic defect layers. Compared with conventional structures, the reflection chromaticity of this structure is insensitive to the incident angle, if the thickness ratio of the cholesteric liquid crystals to that of the isotropic defect layers and the refractive index of periodical isotropic defect layers are properly set. Furthermore, the common forbidden bands for both left and right circular polarizations can be obtained, and we also take the wavelength-dependent refractive indices into consideration and obtain the reflected light chromaticity with the incident angle increasing. The proposed device can be used as a reflective color filter in the display industry. 相似文献