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排序方式: 共有4108条查询结果,搜索用时 625 毫秒
991.
This paper deals with the Ritz method of an integro-differential equation related with Riemann zeta-function. 相似文献
992.
Frank G. Ball Ian L. Dryden Mousa Golalizadeh 《Methodology and Computing in Applied Probability》2008,10(1):1-22
We discuss Brownian motion and Ornstein–Uhlenbeck processes specified directly in planar shape space. In particular, we obtain
the drift and diffusion coefficients of Brownian motion in terms of Kendall shape variables and Goodall–Mardia polar shape
variables. Stochastic differential equations are given and the stationary distributions are obtained. By adding in extra drift
to a reference figure, Ornstein–Uhlenbeck processes can be studied, for example with stationary distribution given by the
complex Watson distribution. The triangle case is studied in particular detail, and some simulations given. Connections with
existing work are made, in particular with the diffusion of Euclidean shape. We explore statistical inference for the parameters
in the model with an application to cell shape modelling.
相似文献
993.
A random motion on the Poincaré half-plane is studied. A particle runs on the geodesic lines changing direction at Poisson-paced
times. The hyperbolic distance is analyzed, also in the case where returns to the starting point are admitted. The main results
concern the mean hyperbolic distance (and also the conditional mean distance) in all versions of the motion envisaged. Also
an analogous motion on orthogonal circles of the sphere is examined and the evolution of the mean distance from the starting
point is investigated. 相似文献
994.
构造奇次同心幻方的一种方法 总被引:1,自引:0,他引:1
杨富锋 《数学的实践与认识》2006,36(5):192-199
幻方是古老的数学游戏,经过几个世纪的发展形成了很多有趣的构造方法.利用行列式的性质和变换得到了构造奇数阶同心幻方原基的一种方法,利用这种方法和排列组合都能得到任意奇数阶幻方的多种形式. 相似文献
995.
In this paper a formula is given for the Dedekind ξ-function, which is similar to that for the Riemann ξ-function. As an application, a lower bound is obtained for the value of the Dedekind ξ-function at the central point. 相似文献
996.
V. P. Maslov 《Mathematical Notes》2006,80(5-6):806-813
We introduce the notion of weight for the asymptotic topological dimension. Planck’s formula for black-body radiation is refined. We introduce the notion of negative asymptotic topological dimension (of hole dimension). The condensate in the hole dimension is applied to the quantized Zipf law for frequency dictionaries (obtained earlier by the author). 相似文献
997.
Smarandache幂函数的均值 总被引:8,自引:2,他引:6
对于给定的自然数n,Smarandache幂函数SP(n)定义为SP(n)=min{m: n|mm,m∈N}.本文研究了这个函数的均值分布性质,并利用解析方法得到了Smarandache幂函数的一个较强的均值公式. 相似文献
998.
Dan Burghelea 《Journal of Functional Analysis》2007,248(1):27-78
In the spirit of Ray and Singer we define a complex-valued analytic torsion using non-selfadjoint Laplacians. We establish an anomaly formula which permits to turn this into a topological invariant. Conjecturally this analytically defined invariant computes the complex-valued Reidemeister torsion, including its phase. We establish this conjecture in some non-trivial situations. 相似文献
999.
Kyoji Saito 《Advances in Mathematics》2007,212(2):645-668
For any tree Γ, we introduce Γ-cones consisting of chambers and enumerate the number of chambers contained in two particular (called principal) Γ-cones. The problem is equivalent to the combinatorial problem of the enumeration of linear extensions of two bipartite orderings on a tree Γ. We characterize the principal Γ-cones among other Γ-cones by the strict maximality of the number of their chambers, and give a formula for this maximal (called principal) number by a finite sum of hook length formulae. We explain the formula through the simplicial block decomposition of principal Γ-cones. The results have their origin and application in the study of the topology related to Coxeter groups and Artin groups. 相似文献
1000.