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1.
The Boltzmann distribution used in the steady-state analysis of the simulated annealing algorithm gives rise to several scale invariant properties. Scale invariance is first presented in the context of parallel independent processors and then extended to an abstract form based on lumping states together to form new aggregate states. These lumped or aggregate states possess all of the mathematical characteristics, forms and relationships of states (solutions) in the original problem in both first and second moments. These scale invariance properties therefore permit new ways of relating objective function values, conditional expectation values, stationary probabilities, rates of change of stationary probabilities and conditional variances. Such properties therefore provide potential applications in analysis, statistical inference and optimization. Directions for future research that take advantage of scale invariance are also discussed.  相似文献   
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Summary Nonstationary regimes of the wave turbulence evolution are considered in the framework of isotropic kinetic equation. It is predicted analytically and confirmed by numerical experiment that there is a class of wave systems in which any initial distribution of the turbulence energy ink-space comes into a universal, Kolmogorovtype spectrum in a finite time. Before and after the formation of the Kolmogorov spectrum, two different self-similar regimes of evolution occur: the first one is responsible for explosively forming the universal spectrum and the second one determines energy dissipation.  相似文献   
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采用对称约简的分析方法,得出了变系数Ginzburg-Landau方程的抛物渐近自相似脉冲解析解的一般表达式.给出了二阶色散系数纵向双曲型变化和纵向指数型变化的色散渐减光纤中自相似脉冲的振幅、啁啾以及脉冲宽度的具体形式,并与数值解进行了对比,其结果符合得很好.从而证实了稀土元素掺杂的色散渐减光纤中,在增益色散因子的影响下,脉冲的演化具有抛物型自相似特性.  相似文献   
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1.IntroductionMotiffedbysomelargedeviationresultsforbranchingparticlesystem,thelargedeviationresultsforsuperprocesseshavebeeninvestigatedrecently.CoxandGffeathll]startedtheinvestigationofthelargedevistionforcriticalbranchingBrochanmotion.IscoeIZIcarr...  相似文献   
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Within the framework of the asymptotic thin-film equations for a highly viscous heavy Newtonian fluid, a hydrodynamic model of non-axisymmetric lava dome growth on a conical surface is constructed. A new class of self-similar solutions describing the flow on a conical surface with finite inclination to the horizontal and a point mass supply at the apex is found analytically for power-law or exponential growth of the liquid volume with time. For a conical surface with a small inclination to the horizontal, the free-surface shape is found numerically. The asymptotics of this solution are compared with the solutions describing the flow on a horizontal plane and a conical surface with finite inclination to the horizontal.  相似文献   
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It is proposed a class of statistical estimators H =(H_1,…,H_d) for the Hurst parameters H =(H_1,…,H_d) of fractional Brownian field via multi-dimensional wavelet analysis and least squares,which are asymptotically normal.These estimators can be used to detect self-similarity and long-range dependence in multi-dimensional signals,which is important in texture classification and improvement of diffusion tensor imaging(DTI) of nuclear magnetic resonance(NMR).Some fractional Brownian sheets will be simulated and the simulated data are used to validate these estimators.We find that when H_i ≥ 1/2,the estimators are accurate,and when H_i 1/2,there are some bias.  相似文献   
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Asymptotic large- and short-time behavior of solutions of the linear dispersion equation μt = Uxxx in IR× IR+, and its (2k+l)th-order extensions are studied. Such a refined scattering is based on a "Hermitian" spectral theory for a pair {B,B*} of non self-adjoint rescaled operators  相似文献   
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分形图形周界和面积的关系   总被引:1,自引:0,他引:1       下载免费PDF全文
 本文讨论分形图形周界和面积的关系;指出:在现实存在的有限层次自相似结构的近似分形图形中,Mandelbrot的周界-面积分维关系不适用。这可能是一些用此方法测出的分维值随码尺大小变化的根本原因。  相似文献   
10.
In this work, we present conditions to obtain a global-in-time existence of solutions to a class of nonlinear viscous transport equations describing aggregation phenomena in biology with sufficiently small initial data in Besov-Morrey spaces and gradient potential as a Radon measure. We also study the self-similarity and asymptotic stability of solutions at large times.  相似文献   
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