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151.
Exact analytic solutions for an elliptic hole with asymmetric collinear cracks in a one-dimensional hexagonal quasi-crystal 下载免费PDF全文
Using the complex variable function method and the technique of conformal mapping, the anti-plane shear problem of an elliptic hole with asymmetric colfinear cracks in a one-dimensional hexagonal quasi-crystal is solved, and the exact analytic solutions of the stress intensity factors (SIFs) for mode Ⅲ problem are obtained. Under the limiting conditions, the present results reduce to the Griffith crack and many new results obtained as well, such as the circular hole with asymmetric collinear cracks, the elliptic hole with a straight crack, the mode T crack, the cross crack and so on. As far as the phonon field is concerned, these results, which play an important role in many practical and theoretical applications, are shown to be in good agreement with the classical results. 相似文献
152.
V. V. Shushunova M. Swillo B. Jaskorzynska M. Qiu L. Thylen 《Journal of Applied Spectroscopy》2003,70(2):298-302
An integrated narrow-band filter for a wavelength of 1.5 m based on the Bragg Si/SiO2 one-dimensional grating coupled to a standard waveguide has been designed. Vector simulation of the dispersion properties and calculation of the operational characteristics of the filter using the method of matching in conjugation with the theory of supermodes were carried out. The full width at the half-maximum level (FWHM) of the transmission spectrum gives the subnanometer range at a filter length of about 1 mm. 相似文献
153.
154.
The determination of the attractor dimension from an experimental time series may be affected by the influence of filters which are incorporated into many measuring processes. While this is expected from the Kaplan-Yorke conjecture, we show that for one-dimensional maps a weak filter can induce a self-similarity which is responsible for the increase of the Hausdorff dimension. We are able to calculate the increase of the generalized dimensionD
q
for the filtered time series of the logistic mapx
i
+1=rx
i
(1–x
i
) atr=4 analytically. 相似文献
155.
We present a method for making rigorous various arguments which predict that certain situations are unstable because of a balance of energy vs. entropy. As applications, we give yet another proof that the two-dimensional plane rotor has no spontaneous magnetization and we make rigorous Thouless' arguments on the one-dimensional Ising model with couplingJ/n
2.on leave from Departments of Mathematics and Physics, Princeton University. Research partially supported by U.S.N.S.F. under grant No. MCS-78-01885.Danforth Fellow. Research partially supported by U.S.N.S.F. under grant No. PHY 78-23952. 相似文献
156.
A K Bandyopadhyay 《Pramana》1982,18(1):49-57
We report the electrical resistivity studies of six quasi one-dimensional organic systems under high pressures up to 8 GPa
and temperatures down to 77K. The room temperature resistivity of these complexes lies in the wide range from 108 ohm cm to 0.05 ohm cm, but they have common features under high pressures. The possible interpretations of these behaviours
have also been discussed. 相似文献
157.
One-dimensional irreducible integrals (k) are computed in the form of Mayerf-function polynomials for a general interparticle potential. Obeisance to the exact specification of the irreducible integral definition produces regularities in the interaction of star graphs with the integration process. Tables of k fork 5 and test solutions are presented. 相似文献
158.
H. J. Hilhorst 《Journal of statistical physics》1977,17(6):413-427
We study by real-space renormalization a class of one-dimensional self-avoiding walks (SAWs) exhibiting a nonzero critical temperature. A linear renormalization transformation is carried out in closed form in a three-parameter subspace of SAW Hamiltonians. We find lines of fixed points along which the degree of localization of the fixed-point interactions varies. The role of the spin rescaling factor in the transformation is explicitly demonstrated. 相似文献
159.
Remco van der Hofstad Achim Klenke Wolfgang König 《Journal of statistical physics》2002,106(3-4):477-520
A polymer chain with attractive and repulsive forces between the building blocks is modeled by attaching a weight e
–
for every self-intersection and e
/(2d) for every self-contact to the probability of an n-step simple random walk on
d
, where , >0 are parameters. It is known that for d=1 and > the chain collapses down to finitely many sites, while for d=1 and < it spreads out ballistically. Here we study for d=1 the critical case = corresponding to the collapse transition and show that the end-to-end distance runs on the scale
n
=
(log n)–1/4. We describe the asymptotic shape of the accordingly scaled local times in terms of an explicit variational formula and prove that the scaled polymer chain occupies a region of size
n
times a constant. Moreover, we derive the asymptotics of the partition function. 相似文献
160.
A. M. Mariz F. van Wijland H. J. Hilhorst S. R. Gomes Júnior C. Tsallis 《Journal of statistical physics》2001,102(1-2):259-283
The Riemann walk is the lattice version of the Lévy flight. For the one-dimensional Riemann walk of Lévy exponent 0<<2 we study the statistics of the support, i.e., set of visited sites, after t steps. We consider a wide class of support related observables M(t), including the number S(t) of visited sites and the number I(t) of sequences of adjacent visited sites. For t we obtain the asymptotic power laws for the averages, variances, and correlations of these observables. Logarithmic correction factors appear for =2/3 and =1. Bulk and surface observables have different power laws for 1<2. Fluctuations are shown to be universal for 2/3 <2. This means that in the limit t the deviations from average M(t)M(t)–M-0304;(t-0304;) are fully described either by a single M independent stochastic process (when 2/3 <1) or by two such processes, one for the bulk and one for the surface observables (when 1<<2). 相似文献