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81.
82.
83.
We consider the dynamics of the lowest order transversal vibration mode of a suspension bridge, for which the hangers are treated as one-sided springs, according to the model of Lazer and McKeena [SIAM Review
58, 1990, 537]. We analyze in particular the multi-stability of periodic attractors and the basin of attraction structure in phase space and its dependence with the model parameters. The parameter values used in numerical simulations have been estimated from a number of bridges built in the United States and in the United Kingdom, thus taking into account realistic, yet sometimes simplified, structural, aerodynamical, and physical considerations. 相似文献
84.
V. A. Khitrov C. Panteleev A. M. Sukhovoj J. Honzátko I. Tomandl 《Physics of Atomic Nuclei》2004,67(10):1818-1822
Main properties of the excited states of 118Sn manifesting themselves in cascade γ decay of its compound state are studied. As in heavier nuclei studied earlier, qualitative interpretation of the whole set
of observed properties of the nucleus appears to be impossible without accounting for coexistence and interaction of quasiparticle
and collective nuclear excitations and their considerable influence on the main parameters of the process under study.
From Yadernaya Fizika, Vol. 67, No. 10, 2004, pp. 1845–1849.
Original English Text Copyright ? 2004 by Khitrov, Panteleev, Sukhovoj, Honzátko, Tomandl.
This article was submitted by the authors in English. 相似文献
85.
86.
C. Torres O. Alejos C. de Francisco J.M. Muñoz P. Hernández-Gómez 《Applied Physics A: Materials Science & Processing》2003,77(3-4):543-547
This paper describes a robust and fast fitting procedure applicable for relaxing processes that cannot be understood as a discrete sum of single processes but require an activation energy distribution. The method is based on a set of closed-form expressions that allow the computation of the relaxation parameters directly from the isochronal curves obtained experimentally. The usefulness of this method is checked by analyzing the isochronal curves given by a theoretical energy distribution and the magnetic disaccommodation spectra observed in yttrium iron garnet (YIG) samples. PACS 02.60.Ed; 75.60.Lr; 75.50.Gg 相似文献
87.
Antal Járai 《Aequationes Mathematicae》2003,65(3):236-266
Summary. We prove that - under certain conditions - measurable solutions $f$ of the functional equation $f(x)=h(x,y,f(g_{1}(x,y)),\ldots,f(g_{n}(x,y))),\quad(x,y)\in D \subset \mathbb{R}^{s} \times \mathbb{R}^{l}$ are continuous, even if $1\le l\le s$. As a tool we introduce new classes of functions which - roughly speaking - interpolate between continuous and Lebesgue measurable functions. Connection between these classes are also investigated. 相似文献
88.
The aim of the paper is to investigate the limit behaviour of the least squares estimator of the shift parameter of nearly unstable, nearly stable, and nearly explosive AR(1) models. Both zero start and stationary cases are treated. Connection with the maximum likelihood estimator of the shift parameter of continuous time AR(1) processes is also discussed. 相似文献
89.
I. Jánossy 《Pramana》2003,61(2):435-445
It is suggested that liquid crystal—polymer interfaces are coupled systems, in which the components mutually influence the
orientational state of each other. The photo-orientation process at liquid crystal-polymer interfaces provides a striking
example of such a coupling. Experiments show that the anisotropic structure generated by polarised light at a polymer surface
is strongly affected by the phase of the liquid crystal covering the polymer. Photo-orientation is significantly more efficient
when the liquid crystal is in the isotropic phase than when it exhibits orientational order. The observations are interpreted
by assuming that in the smectic and nematic phases the liquid crystal stabilises to a large extent polymer chain-segments
aligned parallel to the director, while it blocks the photo-induced formation of chain-segments in the perpendicular direction.
Other situations, in which the coupling between the liquid crystal and the polymer can be important, are also discussed briefly. 相似文献
90.
Periodica Mathematica Hungarica - 相似文献