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971.
In this paper, we estimate the free entropy dimension of the group yon Neumann algebra L(Zt), which is less than 1/t,2 ≤t ≤ +∞. This data is identical with the free dimension defined by Dykema. 相似文献
972.
973.
974.
STATISTICALLY FRACTAL STRENGTH THEORY FOR BRITTLE MATERIALS 总被引:1,自引:0,他引:1
Gao Feng Xie Heping 《Acta Mechanica Solida Sinica》1996,9(1):42-51
Based on the hypothesis of the fractal distribution of crack sizes in brittle materials andthe weakest link principle,the relationship between the fractal dimension of the size-frequency distri-bution of cracks and the Weibull Modulus is derived,which reveals the geometrical nature of theWeibull Modulus.The influences of the size distribution and the orientation distribution of cracks aswell as the irregularity of the crack propagation on the strength are all taken into account.Finally,ageneral expression for the statistical strength of brittle materials in complex tensile stress state is ob-tained. 相似文献
975.
TheHAUSDORFFDIMENSIONANDMEASUREOFTHEGENERALIZEDMORANFRACTALSANDFOURIERSERIES¥RENFUThO;LIANGJINRONGAbstract:Thispaperstudiesth... 相似文献
976.
977.
Nguyen Dinh Cong 《Journal of Dynamics and Differential Equations》1996,8(3):427-467
In this paper linear hyperbolic cocycles are classified by the relation of topological conjugacy. Roughly speaking, two linear cocycles are conjugate if there exists a homeomorphism which maps their trajectories into each other. The problem of classification of discrete-time deterministic hyperbolic dynamical systems was investigated by Robbin (1972). He proved that there exist 4d classes ofd-dimensional deterministic discrete hyperbolic dynamical systems. We obtain a criterion for topological conjugacy of two linear hyperbolic cocycles and show that the number of classes depends crucially on the ergodic properties of the metric dynamical system over which they are defined. Our result is a generalization of the deterministic theorem of Robbin. 相似文献
978.
The use of the Holly-Preissmann two-point scheme has been very popular for the calculation of the dispersion equation. The key to this scheme is to use the characteristics method incorporating the Hermite cubic interpolation technique to approximate the trajectory foot of the characteristics. This method can avoid the excessive numerical damping and oscillation associated with most finite difference schemes for advection computation. On the basis of the fundamental idea of the Holly-Preissmann two-point scheme, a new technique is introduced herein for the computation of the two-dimensional dispersion equation. This new scheme allows the characteristics projecting back several time steps to fall on the spatial or temporal axis, while the characteristics foot is still solved by the Holly-Preissmann two-point method. The diffusion portion of the dispersion equation is solved by the commonly used Crank-Nicholson method. The calculation for these two processes consisting of advection and diffusion is carried out separately but consecutively in one time step, a method known as the split operator algorithm. A hypothetical model was constructed to demonstrate the applicability of this new technique for the calculation of the pure advection and dispersion equation in two dimensions. 相似文献
979.
本文给出一个数量标号的八面形变维数不动点算法,它是Laan和Talman算法的对偶形式。利用这算法,证明了比Freund组合引理更强的结果。另一方面,这算法可用于计算某些连续映射的零点,且具有跟踪连通零点集的功能。 相似文献
980.
耗散孤立波方程的吸引子 总被引:4,自引:1,他引:3
本文研究耗散孤立波方程的长期动力学行为:吸引子的存在性、吸引子的几何结构、耗散系统参数扰动下动力行为、吸引子的分形维估计. 相似文献