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991.
The present paper deals with the long-time behavior of a class of nonautonomous retarded semilinear parabolic differential equations. When the time delays are small enough and the spectral gap conditions hold, the inertial manifolds of the nonautonomous retard parabolic equations are constructed by using the Lyapunov-Perron method. 相似文献
992.
本文通过建立0-1规划模型,设计了一种公务员招聘中的最优录用分配方案,并运用L INGO软件求得了一个实际问题的最优解. 相似文献
993.
By introducing a four-layer step-index waveguide modeling, the characteristics of long-period fiber grating (LPFG) with an nm-thick film overlay, which has higher refractive index than that of fiber cladding are investigated in detail. The influence of both the overlay thickness and refractive index on the tuning ability of LPFG is analyzed. The numerical results demonstrate that spectral response of LPFG is divided into three distinct regions as the overlay deposition increases and the shift of resonant wavelength is drastic in some special thickness range. In conjunction with higher-order cladding mode coupling and fiber cladding etching, the sensitivity of LPFG to the overlay refractive index is enhanced significantly and over 120 nm resonant wavelength tunable range is achieved. 相似文献
994.
A vacuum-deposited aluminium layer (20 nm) is sandwiched between two layers of laminated oriented polypropylene (OPP) film whose thickness varies from 20 to 40 μm. Selected areas of this sealed system were transparentised by the redistribution of the aluminium layer without breaking the seal or causing damage to the OPP film using a 75 W Q-switched Nd:YAG laser. The resultant transparentised films contain aluminium particles, distorted polymer areas and intact areas of the vacuum-coated aluminium layer. This paper investigates the effect of microscopic features upon the overall transmissivity of the laser-treated films and hence the quality of the transparentisation process. 相似文献
995.
Wang Yongqian Liao Xianbo Diao Hongwei Cheng Wenchao Li Guohua Chen Changyong Zhang Shibin Xu Yanyue Chen Weide Kong Guanglin 《中国科学A辑(英文版)》2002,45(10):1320-1328
A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature
of 250°C. The microstructure and local bonding configurations of the films are investigated in detail using micro-Raman scattering,
X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It is found that the films are
structural inhomogeneous, with five phases of Si, Si2O:H, SiO:H, Si2O3:H and SiO2 that coexist. The phase of Si is composed of nonhydrogenated amorphous silicon (a-Si) clusters that are spatially isolated.
The average size of the clusters decreases with the increasing oxygen concentration x in the films. The results indicate that
the structure of the present films can be described by a multi-shell model, which suggests that a-Si cluster is surrounded
in turn by the subshells of Si2O:H, SiO:H, Si2O3:H, and SiO2. 相似文献
996.
997.
This paper discusses a kind of optimization problem with linear complementarity constraints, and presents a sequential quadratic
programming (SQP) algorithm for solving a stationary point of the problem. The algorithm is a modification of the SQP algorithm
proposed by Fukushima et al. [Computational Optimization and Applications, 10 (1998),
5-34], and is based on a reformulation of complementarity condition as a system of linear equations. At each iteration,
one quadratic programming and one system of equations needs to be solved, and a curve search is used to yield the step size.
Under some appropriate assumptions, including the lower-level strict complementarity, but without the upper-level strict
complementarity for the inequality constraints, the algorithm is proved to possess strong convergence and superlinear convergence.
Some preliminary numerical results are reported. 相似文献
998.
Hui-Ling Li De-Jiang Qi Qing-Quan Jiang Shu-Zheng Yang 《International Journal of Theoretical Physics》2006,45(12):2428-2436
An extension of the Parikh-Wilczek's semi-classical quantum tunneling method, the tunneling radiation of the charged particle from a torus-like black hole is investigated. Difference from the uncharged mass-less particle, the geodesics of the charged massive particle tunneling from the black hole is not light-like, but determined by the phase velocity. The derived result shows that the tunneling rate depends on the emitted particle's energy and electric charge, and takes the same functional form as uncharged particle. It proves also that the exact emission spectrum is not strictly pure thermal, but is consistent with the underlying unitary theory.
PACS Numbers: 04.70.Dy, 97.60.Lf, 05.30.Ch. 相似文献
999.
1000.
利用溶胶凝胶法在SiO2Si衬底上沉积高取向的V2O5薄膜,在压强低于2Pa,温度高于400℃的条件下,对V2O5薄膜进行真空烘烤,获得了电阻率变化3个数量级以上、弛豫宽度为62℃的VO2多晶薄膜.以X射线衍射(XRD)、扫描电子显微镜(SEM)图和电阻率转换特性等实验结果为依据,详细分析了溶胶凝胶薄膜在真空烘烤时从V2O5向VO2的转化,它经历了从VnO2n+1(n=2,3,4,6)到VO2的过程.实验证明,根据选择合适的成膜热处理条件和真空烘烤条件是实现溶胶凝胶V2O5结构向VO2结构成功转换的关键
关键词:
溶胶-凝胶法 氧化钒薄膜 VO2膜转换特性 相似文献