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排序方式: 共有3639条查询结果,搜索用时 15 毫秒
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A new multi-scale numerical model is presented using the fractal theory and adopting FEM to simulate the failure of concrete.The relation between the fractal box dimension in large scale and the damage to concrete in small scale is deduced.And the evolutionary process of elastic modulus and strength in small scale is given.Consequently,the multi-scale numerical model is proposed to describe the constitutive relation of concrete between small scale and large scale.A two-dimensional static analysis of a concrete block is performed by using this model and the calculation result is discussed.The propagation of cracks of the concrete block is also studied. 相似文献
224.
Wolfgang Kreitmeier 《Mathematische Nachrichten》2008,281(9):1307-1327
For a large class of dyadic homogeneous Cantor distributions in ?, which are not necessarily self‐similar, we determine the optimal quantizers, give a characterization for the existence of the quantization dimension, and show the non‐existence of the quantization coefficient. The class contains all self‐similar dyadic Cantor distributions, with contraction factor less than or equal to 1/3. For these distributions we calculate the quantization errors explicitly. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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O. Yu. Dashkova 《Siberian Mathematical Journal》2008,49(6):1023-1033
Under study are the solvable nonabelian linear groups of infinite central dimension and sectional p-rank, p ≥ 0, in which all proper nonabelian subgroups of infinite sectional p-rank have finite central dimension. We describe the structure of the groups of this class. 相似文献
227.
陈振龙 《数学物理学报(B辑英文版)》2008,28(4):779-796
Let B^H={B^H(t),t∈R^N+}be a real-valued(N,d)fractional Brownian sheet with Hurst index H=(H1,…,HN).The characteristics of the polar functions for B^H are discussed.The relationship between the class of continuous functions satisfying Lipschitz condition and the class of polar-functions of B^H is obtained.The Hausdorff dimension about the fixed points and the inequality about the Kolmogorov’s entropy index for B^H are presented.Furthermore,it is proved that any two independent fractional Brownian sheets are nonintersecting in some conditions.A problem proposed by LeGall about the existence of no-polar continuous functions satisfying the Holder condition is also solved. 相似文献
228.
229.
Bailin Hao 《Journal of statistical physics》2005,121(5-6):749-757
This is a brief review on critical slowing down near the Feigenbaum period-doubling bifurcation points and its consequences.
The slowing down of numerical convergence leads to an “operational” fractal dimension D=2/3 at a finite order bifurcation point. There is a cross-over to D
0=0.538... when the order goes to infinity, i.e., to the Feigenbaum accumulation point. The problem of whether there exists
a “super-scaling” for the dimension spectrum D
q
W
that does not depend on the primitive word W underlying the period-n-tupling sequence seems to remain open 相似文献
230.
Yutaka Kano 《Annals of the Institute of Statistical Mathematics》1986,38(1):57-68
Summary This paper is concerned with the consistency of estimators in a single common factor analysis model when the dimension of
the observed vector is not fixed. In the model several conditions on the sample sizen and the dimensionp are established for the least squares estimator (L.S.E.) to be consistent. Under some assumptions,p/n→0 is a necessary and sufficient condition that the L.S.E. converges in probability to the true value. A sufficient condition
for almost sure convergence is also given. 相似文献