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51.
Jong Uhn Kim 《Journal of Differential Equations》2004,201(2):201-233
In this paper we study an initial-boundary-value problem for a hyperbolic integro-differential equation with random memory and a random noise. We establish the existence, uniqueness and exponential stability of solutions. Our method consists of finite-dimensional approximation and energy estimates. 相似文献
52.
HOU Zhao-Yu GUO Ai-Qiang 《理论物理通讯》2007,47(4):690-694
We modify the square of virtual photon four-momentum by using nuclear binding energy formula, and calculate the effect of nuclear binding energy to K factor and Compton subprocess and annihilate subprocess in A-A collision Drell-Yan process. The outcome indicates that the effect of nuclear binding energy to K factor is obvious in little x region and it would disappear gradually as x increases. 相似文献
53.
We study the metrical theory of fibred systems, in particular, in the case of continued fraction mixing systems. We get the
limit distribution of the largest value of a continued fraction mixing stationary stochastic process with infinite expectation
and some related results. These are analogous to J. Galambos, W. Philipp, and H. G. Diamond–J. D. Vaaler theorems for the
regular continued fractions. As an application, we see that these theorems hold for Jacobi-Perron algorithm.
Received September 30, 2001; in revised form January 8, 2002 相似文献
54.
J. A. Otero H. Cálas R. Rodríguez-Ramos G. A. Maugin G. Monsiváis R. Pérez-Alvarez 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,55(3):519-533
The transfer matrix and global matrix techniques are
used in the analysis of diffraction of transverse horizontal waves
in piezoelectric superlattices. The system is composed of a set of
different piezoelectric layers with quasiperiodic structure
according to the Fibonacci sequence. The diffraction spectrum of
different configurations of piezoelectric Fibonacci structures is
studied. Numerical results for the diffraction spectrum for the
piezoelectric Fibonacci superlattice are obtained and a comparison
between the results of the transfer and global matrix methods is
given, exhibiting the advantage of the latter. 相似文献
55.
We provide a proof of Connes’ formula for a representative of the Hochschild class of the Chern character for (p,∞)-summable spectral triples. Our proof is valid for all semifinite von Neumann algebras, and all integral p?1. We employ the minimum possible hypotheses on the spectral triples. 相似文献
56.
We present here an improved version of the method introduced by the first author to derive
pointwise gradient estimates for the solutions of one-dimensional parabolic problems. After considering
a general qualinear equation in divergence form we apply the method to the case of a nonlinear
diffusion-convection equation. The conclusions are stated first for classical solutions and then for
generalized and mild solutions. In the case of unbounded initial datum we obtain several regularizing
effects for t > 0. Some unilateral pointwise gradient
estimates are also obtained. The case of
the Dirichlet problem is also considered. Finally, we collect, in the last section, several comments
showing the connections among these estimates and the study of the free boundaries
associated to the solutions of the diffusion-convection equation. 相似文献
57.
The K+−nucleus cross sections have been calculated in relativistic non-linear models taking into account the in-medium modifications of nucleons and mesons properties. More precisely, we have taken into account both the dressing of the nucleon effective mass by the scalar nuclear field in the target and the coupling of the mesons exchanged between the K+ and the nucleons to the polarization of the medium. First, using the most recent relativistic non-linear models, the in-medium σ, ω and ρ meson masses have been obtained in the nuclear matter rest frame. The influence of the non-linear contributions on the K+−nucleus cross sections has then been studied. Finally, we have compared our results with the experimental data. 相似文献
58.
Approximation of a laminated microstructure for a rotationally invariant,double well energy density 总被引:3,自引:0,他引:3
Mitchell Luskin 《Numerische Mathematik》1996,75(2):205-221
Summary. We give error estimates for the approximation of a laminated microstructure which minimizes the energy for a rotationally invariant, double well energy density . We present error estimates for the convergence of the deformation in the convergence of directional derivatives of the deformation in the “twin planes,” the weak convergence of the deformation
gradient, the convergence of the microstructure (or Young measure) of the deformation gradients, and the convergence of nonlinear
integrals of the deformation gradient.
Received July 25, 1995 / Revised version received November 20, 1995 相似文献
59.
This paper deals with the inversive congruential method with power of two modulusm for generating uniform pseudorandom numbers. Statistical independence properties of the generated sequences are studied based on the distribution of triples of successive pseudorandom numbers. It is shown that there exist parameters in the inversive congruential method such that the discrepancy of the corresponding point sets in the unit cube is of an order of magnitude at leastm
–1/3. The method of proof relies on a detailed analysis of certain rational exponential sums. 相似文献
60.