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61.
Ivo Klik 《Journal of statistical physics》1991,62(1-2):389-397
The influence of the Bardeen-Herring back-jump correlations on the Fermi-Dirac statistics of the one-dimensional nonhomogeneous fermionic lattice gas is studied by the Monte Carlo simulation technique and semianalytically. The resulting distribution is obtained, exhibiting increased population of the lower levels in comparison to the Fermi-Dirac statistics. 相似文献
62.
A. Z. Dubničková S. Dubnička M. E. Biagini A. Castro 《Czechoslovak Journal of Physics》1991,41(12):1177-1188
The behaviour of the -hyperon electric and magnetic form factors is predicted within the modified three resonance ((783), (1020), (1680)) vector-meson dominance (VMD) model with correct analytic properties and the asymptotic behaviour predestinated by the quark model for baryons. The resonance couplings to are evaluated from the known couplings to nucleons by utilizing theSU(3) symmetry and normalization conditions for Dirac and Pauli form factors. The masses and widths of the considered vector mesons are fixed at the world averaged values. The optimal position of the effective inelastic threshold, common for Dirac and Pauli form factors, is determined from the fit of the only existing Orsay DM2 point on the
cross section att=5·693 GeV2. The mean square charge and magnetic radii of the -hyperon are found to be r
E
2
=0·018 F2 and r
M
2
=–0·027 F2, respectively.The authors are very much indebted to Prof. R. Baldini-Ferroli for calling their attention to the problem of -hyperon e.m. ff 's in connection with the FENICE experiment. 相似文献
63.
64.
65.
The Boussinesq approximation, where the viscosity depends polynomially on the shear rate, finds more and more frequent use in geological practice. In the paper, this modified Boussinesq approximation is investigated as a dynamical system for which the existence of a global attractor is proved. Finally, a new criterion for estimating the fractal dimension of invariant sets is formulated and its application to the problem under consideration is illustrated. 相似文献
66.
Summary. The iterative aggregation method
for the solution of linear systems is
extended in several directions:
to operators on Banach spaces; to the method with inexact correction, i.e.,
to methods where the (inner) linear system is in turn solved
iteratively; and to the problem of finding
stationary distributions of Markov operators.
Local convergence is shown in all cases.
Convergence results apply to the particular case of stochastic
matrices. Moreover, an argument is given which suggests why the
iterative aggregation method works so well for nearly
uncoupled Markov chains, as well as for Markov chains with
other zero-nonzero structures.
Received
May 25, 1991/Revised version received February 23, 1994 相似文献
67.
In this paper we study the pollution-error in the h-version of the finite element method and its effect on the local quality of a-posteriori error estimators. We show that the pollution-effect in an interior subdomain depends on the relationship between the mesh inside and outside the subdomain and the smoothness of the exact solution. We also demonstrate that it is possible to guarantee the quality of local error estimators in any mesh-patch in the interior of a finite-element mesh by employing meshes which are sufficiently refined outside the patch. 相似文献
68.
69.
J. Badalec J. Ďatlov K. Jakubka VI. Kopecký Š. Körbel L. Kryška P. Magula J. Stöckel F. Žáček S. Nanobashvili 《Czechoslovak Journal of Physics》1983,33(7):787-790
The work is devoted to the study of the LH wave effect on the peripheral plasma of the TM-1-MH tokamak. The observed enhancement of the ion saturated current in the limiter shadow is interpreted as heating of the peripheral ions by absorption of decay waves generated in this region due to the nonlinear wave-plasma interaction. 相似文献
70.
dc ionic conductivity measurements were made on single crystals of Pb(NO3)2 doped with monovalent Na+ and K+ in the temperature range of 100–400°C. In the extrinsic region the conductivity was found to decrease with Na+ having a smaller ionic size, and to increase with K+ with larger ionic size compared to the host Pb ion. Conductivity is attributed to the mobility of anti-Frenkel defects as in the case of PbF2. Dielectric loss measurements were made on the Pb(NO3)2: K+ system in the frequency range of 300 Hz to 20 kHz at different temperatures. Impurity vacancy pairs of the type K+-(NO-3)V are found to be responsible for the observed dielectric loss peaks. The maximum peak frequency is found to increase with temperature. 相似文献