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991.
A classical model of neuronal signal transmission describing the presence of both a threshold and a saturation in the neuron response is considered. This model is used to analyze the transduction by the neuron of various types of information-carrying input signals in the presence of noise. Improvement by noise of the performance via stochastic resonance is established for transmission in both the threshold and the saturation regimes. Stochastic resonance at saturation is a novel form, expressing that the distortion experienced by large input signals transmitted at saturation, can be reduced by addition of noise. 相似文献
992.
In this paper, we investigate a nonlinear Urysohn integral equation on unboundedinterval. We show that under some assumptions that the equation has monotonic solutions belonging to the space of functions being Lebesgue integrable on unbounded interval. The main tool used in our study is the technique associated with measures of weak noncompactness and measures of noncompactness in strong sense. 相似文献
993.
In this paper we investigate on the existence of the stabilizing solution of the algebraic Riccati equation (ARE) related to the
filtering problem with a prescribed attenuation level γ. It is well known that such a solution exists and is positive definite for γ larger than a certain γF and it does not exist for γ smaller than a certain γ0. We consider the intermediate case γ(γ0,γF] and show that in this interval the stabilizing solution does exist, except for a finite number of values of γ. We show how the solution of the ARE may be employed to obtain a minimum-phase J-spectral factor of the J-spectrum associated with the
filtering problem. 相似文献
994.
Perturbation Analysis of Multiclass Stochastic Fluid Models 总被引:1,自引:5,他引:1
Gang Sun Christos G. Cassandras Christos G. Panayiotou 《Discrete Event Dynamic Systems》2004,14(3):267-307
We use a stochastic fluid model (SFM) to capture the operation of finite-capacity queueing systems with multiple customer classes. We derive gradient estimators for class-dependent loss and workload related performance metrics with respect to any one of several threshold parameters used for buffer control. These estimators are shown to be unbiased and directly observable from a sample path without any knowledge of underlying stochastic characteristics of the traffic processes. This renders them computable in on-line environments and easily implementable in settings such as communication networks. 相似文献
995.
We report on a computational approach based on the self-consistent solution of the steady-state Boltzmann transport equation coupled with the Poisson equation for the study of inhomogeneous transport in deep submicron semiconductor structures. The nonlinear, coupled Poisson-Boltzmann system is solved numerically using finite difference and relaxation methods. We demonstrate our method by calculating the high-temperature transport characteristics of an inhomogeneously doped submicron GaAs structure where the large and inhomogeneous built-in fields produce an interesting fine structure in the high-energy tail of the electron velocity distribution, which in general is very far from a drifted-Maxwellian picture. 相似文献
996.
Atsushi Sakai Yoshinari Kamakura Kenji Taniguchi 《Journal of Computational Electronics》2004,3(3-4):449-452
We report the two- and three-dimensional quantum lattice-gas automata simulation for one-particle electronic wave propagation in nanostructures. The transmission coefficient of the electronic wave through the two-dimensional quantum point contact is investigated taking account of the surface roughness of the confinement wall. It is demonstrated that the electron transmission is significantly affected by the surface roughness pattern even if the same roughness parameter is assumed. We also perform the three-dimensional simulation, and the wave propagation in the structure like an ultrathin-body MOSFET is visualized. 相似文献
997.
998.
本文对Burgers'方程采用特征混合有限元方法进行数值模拟,证明了特征混合元格式的稳定性。作为数值例子,我们计算了正弦波传播和冲击波传播,通过与混合元和有限元方法的比较,说明了该方法在粘性系数逐渐减小时对锋线前沿处理的有效性。 相似文献
999.
本文研究小周期结构Helmholtz方程的多尺度计算。我们用各向异性多尺度方法(HMM)求解小周期结构Helmholtz问题。借助于渐近分析技术,在对HMM方法深入分析的基础上,我们给出了精确与HMM方法近似解之间的误差估计,并讨论和分析了利用微结构信息校正HMM逼近解的技巧。最后,我们用数值例了验证了理论结果的正确性。 相似文献
1000.