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161.
I. Grabec 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,22(1):129-135
A physical law is represented by the probability distribution of a measured variable. The probability density is described
by measured data using an estimator whose kernel is the instrument scattering function. The experimental information and data
redundancy are defined in terms of information entropy. The model cost function, comprised of data redundancy and estimation
error, is minimized by the creation-annihilation process.
Received 24 February 2000 and Received in final form 21 February 2001 相似文献
162.
163.
The paper is concerned with the eigenvalue problems for piezoelectric bodies with voids in contact with massive rigid plane punches and coved by the system of open-circuited and short-circuited electrodes. The linear theory of piezoelectric materials with voids for porosity change properties according to Cowin–Nunziato model is used. The generalized statements for eigenvalue problem are obtained in the extended and reduced forms. A variational principle is constructed which has the properties of minimality, similar to the well-known variational principle for problems with pure elastic media. The discreteness of the spectrum and completeness of the eigenfunctions are proved. The orthogonality relations for eigenvectors are obtained in different forms. As a consequence of variational principles, the properties of an increase or a decrease in the natural frequencies, when the mechanical, electric and “porous” boundary conditions and the moduli of piezoelectric solid with voids change, are established. 相似文献
164.
G.G.M. Coppa A. D'Angola 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(4):533-539
The paper deals with the stationary distribution of charged particles moving in a material medium, having scattering and absorption
properties, in which a uniform electric field is present. The purpose of the work is finding analytical solutions in simplified
but physically significant situations and comparing different approximations based on a spherical-harmonics expansion of the
velocity distribution.
Received: 28 July 1998 相似文献
165.
A. Bhattacharyay J.K. Bhattacharjee 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,8(1):137-141
Reaction diffusion systems can exhibite both spatial and temporal patterns. We show that the effect of spatial variation of
the removal rate can have significant effect on the stability boundaries. In particular there can be a case of parametric
resonance.
Received 11 March 1998 相似文献
166.
M. B. Suryanarayana 《Journal of Optimization Theory and Applications》1976,19(1):125-140
In the context of a recent geometric condition of Cesari, used in the reduction of seminormality requirements in lower closure theorems, this paper shows that the existence of a strongly convergent selection from the sequence of orientor fields, under Kuratowski property (K), is adequate to guarantee lower closure theorems. This generalization is justified through examples. Several related remarks are made.This work was done in the framework of Research Project AFOSR-71-2122 at the University of Michigan, Ann Arbor, Michigan. The author wishes to thank Professor L. Cesari for helpful discussions during the writing of this paper. 相似文献
167.
J. Iwaniszewski 《Il Nuovo Cimento D》1995,17(7-8):819-825
Summary The phenomenon of stochastic resonance is predicted in a monostable system displaying transient bimodality during the evolution.
The signal-to-noise ratio as a function of the noise intensity calculated within the rate equation theory with many simplifying
assumptions exhibits a promising peak. The numerical simulations are also reported.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba, 5–10 June 1994. 相似文献
168.
A. J. W. Duijvestijn 《BIT Numerical Mathematics》1972,12(3):318-324
The correctness of an in-place permutation algorithm is proved. The algorithm exchanges elements belonging to a permutation cycle. A suitable assertion is constructed from which the correctness can be deduced after completion of the algorithm.An in-place rectangular matrix transposition algorithm is given as an example. 相似文献
169.
W. Kwang-Hua Chu J. Fang 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,16(3):543-547
Continuum-mechanic derivation of the entrainment of rarefied gases induced by a surface wave along walls (or peristaltic transport)
in a confined parallel-plane microchannel is conducted by the perturbation method. Both no-slip and slip flow cases are investigated
with the former ones matched with the previous approach by Fung and Yih. Critical reflux values due to first order slip-flow
effects become trivial for the free pumping case, and decrease due to second order slip-flow effects after we compared them
with no-slip cases.
Received 27 August 1999 and Received in final form 10 January 2000 相似文献
170.
We show that the S-matrix for electrons propagating in a waveguide has different statistical properties depending on whether the waveguide cavity shape gives rise to chaotic or integrable behavior classically. We obtain distributions of energy level spacings for integrable and chaotic billiards shaped like the waveguide cavity. We also obtain distributions for Wigner delay times and resonance widths for the waveguide, for integrable and chaotic cavity geometries. Our results, obtained by direct numerical calculation of the electron wave function, are consistent with the predictions of random matrix theory. 相似文献