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981.
在弱$L_p$空间之间建立一类Marcienkiewicz型内插定理并且给出它在现代调和分析理论中的某些应用. 相似文献
982.
Toeplitz-Bezout矩阵的若干性质 总被引:1,自引:0,他引:1
从定义出发,利用矩阵生成函数的方法来研究Toeplitz-Bezout若干基本性质,同时利用极限的思想将其对角约化. 相似文献
983.
We study the equidistribution on spheres of the n-step transition probabilities of random walks on graphs. We give sufficient conditions for this property being satisfied and for the weaker property of asymptotical equidistribution. We analyze the asymptotical behaviour of the Green function of the simple random walk on 2 and we provide a class of random walks on Cayley graphs of groups, whose transition probabilities are not even asymptotically equidistributed. 相似文献
984.
C. Blanc M. Kléman 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,10(1):53-60
In the quasi-ternary CPCl/brine/hexanol lyotropic system, the interface of the lamellar and L3 sponge phases displays a phenomenon of epitaxy: the layers of the lamellar phase tend to make a constant non-trivial angle
with the interface. Thin samples of lamellar phase embedded in the sponge phase are thus submitted to oblique anchoring conditions
and defects are created in the lamellar phase in order to satisfy the bulk lamellar ordering and the boundary conditions.
We have studied small droplets of lamellar phase in the sponge phase. They do not exhibit the classic defects (focal conic domains) but wall defects, which appear in order to satisfy the smectic elasticity and the boundary
conditions. Moreover we show through experiments in controlled geometry that, even in the presence of focal conic domains,
wall defects control the size and periodicity of the textures which are observed at the interface.
Received 4 November 1998 相似文献
985.
A lattice random walk model based on particles scattering on discrete lattice of homogenous space is introduced. The discrete Green's function (DFG) for two-dimensional and three-dimensional lattice random walk of photon is found and proved by mathematical induction. The convolution theorem of photon lattice random walk is presented. They can be used with the method of images to calculate the photon density distribution in semi-infinite and finite slab homogenous turbid media such as tissue. 相似文献
986.
A. C. Ting 《Journal of Optimization Theory and Applications》1977,22(4):487-508
A convergence analysis is presented for a general class of derivative-free algorithms for minimizing a functionf(x) for which the analytic form of the gradient and the Hessian is impractical to obtain. The class of algorithms accepts finite-difference approximation to the gradient, with stepsizes chosen in such a way that the length of the stepsize must meet two conditions involving the previous stepsize and the distance from the last estimate of the solution to the current estimate. The algorithms also maintain an approximation to the second-derivative matrix and require that the change inx made at each iteration be subject to a bound that is also revised automatically. The convergence theorems have the features that the starting pointx
1 need not be close to the true solution andf(x) need not be convex. Furthermore, despite the fact that the second-derivative approximation may not converge to the true Hessian at the solution, the rate of convergence is still Q-superlinear. The theorry is also shown to be applicable to a modification of Powell's dog-leg algorithm. 相似文献
987.
等效电子组态(l1+l1-)的谱项波函数及能量矩阵的电子杨表表示 总被引:4,自引:0,他引:4
把电子组态(l^1 l^1-)给出的填布杨图称为电子杨表,给出了有关电子杨表与无微扰波函数之间的对应关系式,证明了电子杨表的正交归一性质,给出了电子组态(l^1 l^1-)谱项波函数的电子杨表表示,证明了由电子杨表给出的(l^1 l^1-)电子组态的能量矩阵为对角矩阵。 相似文献
988.
989.
P. J. Forrester 《Journal of statistical physics》1994,76(1-2):331-346
A new quantum many-body Hamiltonian is introduced, for which the exact ground state is a Jastrow-type product. This Hamiltonian is interpreted as a one-component |x|-potential Coulomb system in free boundary conditions, and by explicit calculation it is shown that the ground state is crystalline. The generaln-body density matrix is calculated, and is related to then-body density matrix calculated in periodic boundary conditions. 相似文献
990.
R. I. Petrova V. P. Perelygin A. B. Akopova M. M. Gogorjan 《Radiation measurements》1995,25(1-4):329-330
The investigation of the track etching velocity dependence for nuclei with Z50 on pH of the etching solution in the olivine crystals from Marjalahti and Eagle Station meteorites, containing galactic cosmic-ray nuclear tracks and also the crystals from Marjalahti meteorite, calibrated at the UNILAC (GSI, Darmstadt) with 14.17 MeV/N 208Pb nuclei, were performed.
The pH of the etching solution were changed from 7.8 to 9.4. It is shown that the optimal track etch condition were realised at pH of etching solution in the interval from 8.4 to 8.8.
The results of the Galactic cosmic-ray nuclei tracks with Z83 revealed in olivine crystals are presented. They were additionally irradiated at 90% to the surface with accelerated 14 MeV/N 132Xe nuclei. 相似文献