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排序方式: 共有486条查询结果,搜索用时 15 毫秒
21.
On the distribution of the length of the longest increasing subsequence of random permutations 总被引:18,自引:0,他引:18
Jinho Baik Percy Deift Kurt Johansson 《Journal of the American Mathematical Society》1999,12(4):1119-1178
The authors consider the length, , of the longest increasing subsequence of a random permutation of numbers. The main result in this paper is a proof that the distribution function for , suitably centered and scaled, converges to the Tracy-Widom distribution of the largest eigenvalue of a random GUE matrix. The authors also prove convergence of moments. The proof is based on the steepest descent method for Riemann-Hilbert problems, introduced by Deift and Zhou in 1993 in the context of integrable systems. The applicability of the Riemann-Hilbert technique depends, in turn, on the determinantal formula of Gessel for the Poissonization of the distribution function of .
22.
In this paper, we derive a stochastic model for the HIV epidemic in homosexual populations involving age and race. To account for effects of different mixing patterns, a low risk selection rule is introduced. The model is then formulated in terms of chain multinomial distributions by means of which the means are derived. Some simulation studies by computer indicate clearly that age and race have a significant impact on the HIV epidemic. 相似文献
23.
The practical realization of rotor-synchronized mixing-times in 2D-MAS exchange experiments without the need for a special hardware is reviewed; its consequence for the ‘true mixing time' of the experiment is discussed. We demonstrate influences on experimental rate constants derived from such experiments as well as on the appearance of the 2D-MAS spectra, taken at short mixing times. 相似文献
24.
Dispersive flow of disks through a
two-dimensional Galton board 总被引:1,自引:0,他引:1
We report here an experimental and numerical study of the
flow properties of disks driven by gravity through a hexagonal
lattice of obstacles, i.e. a
Galton board. During the fall, particles experience dissipative
collisions that scatter them in random directions. A
driven-diffusion regime can be achieved under certain
conditions. A characteristic length of the motion and its
dependence on geometrical parameters of the system is analyzed
in the steady regime. The influence of collective effects on the
dispersion process is investigated by comparison between single-
and many-particle flows. The characterization of the dynamics
and the diffusive properties of the flow in a system like a
Galton board can be expanded to other granular systems,
particularly static solid particle mixers and will give some
insight in understanding granular mixing. 相似文献
25.
We have experimentally and analytically studied transport of a passive scalar in the wake of a thin flat plate located at
the centerline of a planar contraction with flat walls. The constant Launder parameter in the contraction, K = 6.25 ×10 − 6, was twice the value required for a turbulent boundary layer to relaminarize. In addition to the mixing analysis inside the
contraction, layer mixing is also investigated downstream, where the flow continues inside a constant cross-section channel.
In order to generate the passive scalar, the airflow above the plate was heated and the temperature stratification in the
wake was traced by measuring the temperature field using constant current anemometry. Using different plate lengths, we found
that the degree of mixing, obtained at a given position in the straight channel, is a function of the distance from the plate
trailing edge to the contraction outlet. For a plate which does not protrude into the straight channel, we demonstrate the
existence of an optimal trailing edge-contraction outlet distance that results in the lowest possible degree of mixing at
a given downstream position in the straight channel. This finding is also supported by a semi-empirical relationship based
on our developed self-similar solution for mixing layers in planar contractions. 相似文献
26.
ρ混合、φ混合、ψ混合线性模型M估计的强相合性 总被引:2,自引:3,他引:2
研究了 ρ混合、φ混合、ψ混合样本线性模型中回归参数M估计的强相合性 ,在条件不变的情况下 ,获得与独立情形一样的M估计是强相合的充分条件 ,推广了文 [1 ]定理 2 . 相似文献
27.
28.
Numerical simulation of nanoparticle nucleation and coagulation in a mixing layer with sulfuric acid vapor binary system is performed using the large eddy simulation and the direct quadrature method of moment. The distributions of number concentration, volume concentration, and average diameter of nanoparticles are obtained. The results show that the coherent structures have an important effect on the distributions of number concentration, volume concentration and average diameter of nanoparticles via continuously transporting and diffusing the nanoparticles to the area of low particle concentration. In the streamwise direction, the number concentration of nanoparticles decreases, while the volume concentration and the average diameter increase. The distributions of number concentration, volume concentration and average diameter of nanoparticles are spatially inhomogeneous. The characteristic time of nucleation is shorter than that of coagulation. The nucleation takes place more easily in the area of low temperature because where the number concentration of nanoparticles is high, while the intensity of coagulation is mainly affected by the number concentration. Both nucleation and coagulation result in the variation of average diameter of nanoparticles. 相似文献
29.
30.
α-混合序列和的强大数律及其应用 总被引:1,自引:0,他引:1
杨善朝 《高校应用数学学报(A辑)》1996,(4)
研究α-混合序列加权和的强大数律,并将这些结果应用于Priestley,M.B.和Chao,M.T.(1972)提出的非参数回归函数加权核估计,获得较理想结论. 相似文献