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121.
In this paper, a chemostat model with variable yield and impulsive state feedback control is considered. We obtain sufficient conditions of the globally asymptotical stability of the system without impulsive state feedback control. We also obtain that the system with impulsive state feedback control has periodic solution of order one. Sufficient conditions for existence and stability of periodic solution of order one are given. In some cases, it is possible that the system exists periodic solution of order two. Our results show that the control measure is effective and reliable. 相似文献
122.
In this paper, we study Web cache hit rates by introducing a birth–death model. A system consisting of a single Web server with a single cache stores Web pages that are classified as hot pages (popular pages) and cold pages (less popular pages). Given requested probabilities for each class, the stochastic model provides the mean hit rate for a random replacement algorithm and the upper and low bounds for other algorithms. Numerical results from the analysis are validated using the output of simulation programs that utilize the LRU algorithm. 相似文献
123.
N. Kawamura K. Nagamine T. Matsuzaki K. Ishida S. N. Nakamura Y. Matsuda M. Tanase M. Kato K. Kurosawa H. Sugai K. Kudo N. Takeda G. H. Eaton 《Hyperfine Interactions》2001,138(1-4):235-240
A systematic study on muon catalyzed fusion (μCF) was conducted in solid deuterium and tritium (D–T) mixture. A variety of
experimental conditions were investigated, i.e., tritium concentrations from 20 to 70%, temperatures from 5 to 16 K. A preliminary
analysis result suggests a steep decrease in the dtμ-molecule formation rate with decreasing temperature, and also an increase in the probability for a muon reactivation after
an α-sticking phenomenon.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
124.
For neural networks with all the parameters unknown, we focus on the global robust synchronization between two coupled neural networks with time-varying delay that are linearly and unidirectionally coupled. First, we use Lyapunov functionals to establish general theoretical conditions for designing the coupling matrix. Neither symmetry nor negative (positive) definiteness of the coupling matrix are required; under less restrictive conditions, the two coupled chaotic neural networks can achieve global robust synchronization regardless of their initial states. Second, by employing the invariance principle of functional differential equations, a simple, analytical, and rigorous adaptive feedback scheme is proposed for the robust synchronization of almost all kinds of coupled neural networks with time-varying delay based on the parameter identification of uncertain delayed neural networks. Finally, numerical simulations validate the effectiveness and feasibility of the proposed technique. 相似文献
125.
Hiroyoshi Mitake 《Applied Mathematics and Optimization》2008,58(3):393-410
We study Hamilton-Jacobi equations in a bounded domain with the state constraint boundary condition. We establish a general
convergence result for viscosity solutions of the Cauchy problem for Hamilton-Jacobi equations with the state constraint boundary
condition to asymptotic solutions as time goes to infinity. 相似文献
126.
共线快离子束一激光光谱学具有选择性激发、测量精度高等优点而被用于研究原子、分子和离子的同位素位移、激发寿命和超精细结构.介绍了利用快离子束一激光共线技术测量NdⅡ亚稳态4f~45d~6K_(13/2)和激发态(25524)~0_(13/2)的超精细结构,并定出相应的超精细相互作用常数. 相似文献
127.
N. I. Shamrov 《Journal of Applied Spectroscopy》2001,68(4):568-574
The equations of the semiclassical theory for the stimulated resonant coherent Raman scattering (SRS) in an extended medium have been solved numerically. The distribution function of the energy of Stokes pulses at different detunings and energies of a laser has been determined. Just as for the nonresonant coherent SRS, in the situation considered there occurs transition from the large–scale fluctuation mode to the mode of relatively small straggling of the energies of Stokes pulses with increase in the pumping energy. With approach to the resonance, the energy required to stabilize the Stokes radiation decreases. 相似文献
128.
张方玉 《大理学院学报:综合版》2000,(2)
大理祥云的水目山是著名的佛教名山,大理历史上是佛教胜地。学界时大理佛教的传播有诸多说法,本文从水 目山的部分古碑刻记载进行考释,提出了佛教于中唐传入大理,早先传入的是汉地密宗等论点。 相似文献
129.
本文以扰动理论为基础建立了电解质溶液的状态方程。并将其用于电解质水溶液的固—液平衡计算。同时与Guggenheim模型,Bromley模型,Meissner模型和Pitzer模型进行了比较。本文模型与Bromley模型,Meissner模型及Pitzer模型具有大致相同的精度。取得了令人满意的结果。 相似文献
130.
用一种无声放电方法,使反应器中N2-H2O介质在高频高压电场作用下产生OH,以促进燃烧反应,抑制碳烟生成,并开发一种追踪化学反应的分子物理测量手段,用共振吸收光谱法测定OH浓度。 相似文献