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991.
M. Rudolph A. Destexhe 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,52(1):125-132
Systems driven by Poisson-distributed quantal inputs can be described as
“shot noise” stochastic processes. This formalism can apply to neurons
which receive a large number of Poisson-distributed synaptic inputs of similar
quantal size. However, the presence of temporal correlations between these
inputs destroys their quantal nature, and such systems can no longer be
described by classical shot noise processes. Here, we show that explicit
expressions for various statistical properties, such as the amplitude
distribution and the power spectral density, can be deduced and investigated
as functions of the correlation between input channels. The monotonic behavior
of these expressions allows an one-to-one relation between temporal
correlations and the statistics of fluctuations. Multi-channel shot noise
processes, therefore, open a way to deduce correlations in input patterns by
analyzing fluctuations in experimental systems. We discuss applications such
as detecting correlations in networks of neurons from intracellular recordings
of single neurons. 相似文献
992.
P. Puri 《Rheologica Acta》1984,23(4):451-453
The problem of the impulsive motion of a flat plate in a Rivlin-Ericksen fluid is reconsidered. An exact solution for the velocity distribution is found in terms of a definite integral. It is shown that a solution obtained earlier does not satisfy the boundary condition at the plate in the sense of generalized functions. 相似文献
993.
A Particle Migrating Randomly on a Sphere 总被引:4,自引:0,他引:4
David R. Brillinger 《Journal of Theoretical Probability》1997,10(2):429-443
Consider a particle moving on the surface of the unit sphere in R
3 and heading towards a specific destination with a constant average speed, but subject to random deviations. The motion is modeled as a diffusion with drift restricted to the surface of the sphere. Expressions are set down for various characteristics of the process including expected travel time to a cap, the limiting distribution, the likelihood ratio and some estimates for parameters appearing in the model. 相似文献
994.
基于修正的Clough-Penzien地震动模型时MTMD的动力特性 总被引:3,自引:0,他引:3
研究了由许多刚度和阻尼保持常量而频率呈线性分布的TMD形成的MTMD的地震特性,基于虚拟激励法和本文提出的平稳过滤有色噪声地震动模型(修正的Clough-Penzien地震动模型),建立了结构-MTMD系统的传递函数,进而导出了设置MTMD时结构的动力放大系数(DMF)明确表达式。MTMD的优化准则可选为最大动力放大系数的最小值的最小化(Min.Min.Max.DMF)。通过最优搜寻可得MTMD的最优频率间隔、平均阻尼比、调谐频率比和相应的无量纲控制有效性指标。考虑结构受控频率与场地土卓越频率比的不同取值和不同场地类型,研究了场地土卓越频率和场地类型对MTMD最优参数及有效性的影响。而且,为比较,基于Clogh-Penzien地震动模型和不考虑地震动模型的结果也被考虑。 相似文献
995.
Hiroyuki Matsumoto 《Journal of Functional Analysis》2007,244(2):565-578
By using an explicit representation for the horizontal lift of the Brownian motion on the Poincaré upper half-plane H2, we show an expression for the heat kernel for the de Rham-Kodaira Laplacian on H2. We apply the result to a study on the Selberg trace formula. 相似文献
996.
Starting from the addition formula for q-disk polynomials, which is an identity in noncommuting variables, we establish a basic analogue in commuting variables of
the addition and product formula for disk polynomials. These contain, as limiting cases, the addition and product formula
for little q-Legendre polynomials. As q tends to 1 the addition and product formula for disk polynomials are recovered.
Date received: September 29, 1995. Date revised: May 20, 1996. 相似文献
997.
用独立变量表示的约束Birkhoff系统的运动稳定性 总被引:1,自引:1,他引:0
首先提出Pfaff-Birkhoff-D'Alembert原理,并由此原理导出约束Birkhoff系统用独立交量表示的运动方程;其次建立系统的受扰运动微分方程;最后利用直接法和一次近似理论得到系统运动稳定性的一些判据. 相似文献
998.
We consider finite-dimensional reductions (truncations) of discrete systems of the type of the Toda chain with discrete time that retain the integrability. We show that for finite-dimensional chains, in addition to integrals of motion, we can construct a rich family of higher symmetries described by the master symmetry. We reduce the problem of integrating a finite-dimensional system to the implicit function theorem. 相似文献
999.
Moser扭转定理在Lgrange稳定性中的应用 总被引:1,自引:0,他引:1
本文利用Moser扭转定理证明了一类Duffing方程x″+g(x)=e(t)的Lagrange稳定性,其中e(t)以1为周期,g:R→R具有下列性质:当x≥d0时,g(x)是超线性的;当x≤-d0时,9(x)是次线性的,其中d0悬一正常数. 相似文献
1000.
A Superprocess with coalescing spatial motion is constructed in terms of one-dimensional excursions. Based on this construction, it is proved that the superprocess is purely atomic and arises as scaling limit of a special form of the superprocess with dependent spatial motion studied in Dawson et al. (Refs. 5, 19–20). 相似文献