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991.
Yang Zhijian 《Mathematical Methods in the Applied Sciences》2002,25(10):825-833
We consider the blowup of solutions of the initial boundary value problem for a class of non‐linear evolution equations with non‐linear damping and source terms. By using the energy compensation method, we prove that when p>max{m, α}, where m, α and p are non‐negative real numbers and m+1, α+1, p+1 are, respectively, the growth orders of the non‐linear strain terms, damping term and source term, under the appropriate conditions, any weak solution of the above‐mentioned problem blows up in finite time. Comparison of the results with the previous ones shows that there exist some clear condition boundaries similar to thresholds among the growth orders of the non‐linear terms, the states of the initial energy and the existence and non‐existence of global weak solutions. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
992.
Hui-Qing Lu Li-Ming Shen Guo-Hong Yang Y. Y. Lai K. S. Cheng 《International Journal of Theoretical Physics》2002,41(5):939-951
We apply the theory developed in quantum cosmology to a model of charged generalized Brans–Dicke gravity. This is a quantum model of gravitation interacting with a charged Brans–Dicke type scalar field which is considered in the Pauli frame. The Wheeler–DeWitt equation describing the evolution of the quantum Universe is solved in the semiclassical approximation by applying the WKB approximation. The wave function of the Universe is also obtained by applying both the Vilenkin-like and the Hartle–Hawking-like boundary conditions. We then make predictions from the wave functions and infer that the Vilenkin's boundary condition is more reasonable in the Brans–Dicke gravity models leading a large vacuum energy density at the beginning of the inflation. 相似文献
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997.
Patterned uniformly (100)-orientated silicon nanocrystallite (SiNC) films were fabricated based on hydrogen ion implantation technique and typical electrochemical anodic etching method. The surface morphology and microstructure characteristics of the films were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and atomic force microscopy. The efficient field emission with low turn-on field of about 3.2 V/μm at current density of 0.1 μA/cm2 was obtained. The emission current density from the SiNC films reached 1 mA/cm2 under a bias field of about 11 V/μm. The experimental results demonstrate that the SiNC films have great potential applications for flat panel displays. 相似文献
998.
Polaron effects on third-harmonic generation (THG) in cylindrical quantum wires with a finite confining potential are investigated. The THG coefficient is obtained by using the compact-density-matrix approach and an iterative method, and the numerical results are presented for GaAs/AlAs cylindrical quantum wires. The results show that the THG coefficient is greatly enhanced and the peak shift to the aspect of high energy when considering the influence of electron-phonon interaction. 相似文献
999.
Wenran Feng Chizi Liu Guangliang Chen Guling Zhang Weichao Gu Erwu Niu Si-Ze Yang 《Applied Surface Science》2007,253(11):4923-4927
Hard films prepared by pulsed high energy density plasma (PHEDP) are characterized by high film/substrate adhesive strength, and high wear resistance. Titanium carbonitride (TiCN) films were deposited onto YG11C (ISO G20) cemented carbide cutting tool substrates by PHEDP at room temperature. XRD, XPS, SEM, AES, etc. were adopted to analyze the phases (elements) composition, microstructure and the interface of the films, respectively. The results show that, the uniform dense films are composed of grains ranging from 70 to 90 nm. According to the AES result, there is a broad transition layer between the film and the substrate, due to the ion implantation effect of the PHEDP. The transition layer is favorable for the film/substrate adhesion. 相似文献
1000.
具有位相型修理的离散时间可修排队系统 总被引:1,自引:0,他引:1
本文研究了具有一般独立输入,位相型修理的离散时间可修排队系统,假定服务台对顾客的服务时间和服务台寿命服从几何分布,运用矩阵解析方法我们给出系统嵌入在到达时刻的稳态队长分布和等待时间分布,并证明这些分布均为离散位相型分布.我们也得到在广义服务时间内服务台发生故障次数的分布,证明它服从一个修正的几何分布.我们对离散时间可修排队与连续时间可修排队进行了比较,说明这两种排队系统在一些性能指标方面的区别之处.最后我们通过一些数值例子说明在这类系统中顾客的到达过程、服务时间和服务台的故障率之间的关系. 相似文献