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861.
Bruzón M. S. Gandarias M. L. Muriel C. Ramírez J. Saez S. Romero F. R. 《Theoretical and Mathematical Physics》2003,137(1):1367-1377
We use the classical and nonclassical methods to obtain symmetry reductions and exact solutions of the (2+1)-dimensional integrable Calogero–Bogoyavlenskii–Schiff equation. Although this (2+1)-dimensional equation arises in a nonlocal form, it can be written as a system of differential equations and, in potential form, as a fourth-order partial differential equation. The classical and nonclassical methods yield some exact solutions of the (2+1)-dimensional equation that involve several arbitrary functions and hence exhibit a rich variety of qualitative behavior. 相似文献
862.
R Teunter E van der Laan D Vlachos 《The Journal of the Operational Research Society》2004,55(5):475-484
We describe hybrid manufacturing/remanufacturing systems with a long lead time for manufacturing and a short lead time for remanufacturing. We review the classes of inventory strategies for hybrid systems in the literature. These are all based on equal lead times. For systems with slow manufacturing and fast remanufacturing, we propose a new class. An extensive numerical experiment shows that the optimal strategy in the new class almost always performs better and often much better than the optimal strategies in all other classes. 相似文献
863.
R. Tijdeman 《Indagationes Mathematicae》2003,14(1):135-147
Let w = w1 … wn be a word of maximal length n, and with a maximal number of distinct letters for this length, such that w has periods p1, …, pn but not period gcd(p1,…,pr). We provide a fast algorithm to compute n and w. We show that w is uniquely determined apart from isomorphism and that it is a palindrome. Furthermore we give lower and upper bounds for n as explicit functions of p1, …pr. For r = 2 the exact value of n is due to Fine and Wilf. In case the number of distinct letters in the extremal word equals r a formula for n had been given by Castelli, Mignosi and Restivo in case r = 3 and by Justin if r > 3. 相似文献
864.
J. F. R. Archilla J. Cuevas B. Snchez-Rey A. Alvarez 《Physica D: Nonlinear Phenomena》2003,180(3-4):235-255
Whereas there exists a mathematical proof for one-site breathers stability, and an unpublished one for two-site breathers, the methods for determining the stability properties of multibreathers rely on numerical computation of the Floquet multipliers or on the weak nonlinearity approximation leading to discrete nonlinear Schrödinger equations. Here we present a set of multibreather stability theorems (MST) that provides a simple method to determine multibreathers stability in Klein–Gordon systems. These theorems are based in the application of degenerate perturbation theory to Aubry’s band theory. We illustrate them with several examples. 相似文献
865.
Dynamics of Multisection Semiconductor Lasers 总被引:1,自引:0,他引:1
We consider a mathematical model (the so-called traveling-wave system) which describes longitudinal dynamical effects in semiconductor lasers. This model consists of a linear hyperbolic system of PDEs, which is nonlinearly coupled with a slow subsystem of ODEs. We prove that a corresponding initial-boundary value problem is well posed and that it generates a smooth infinite-dimensional dynamical system. Exploiting the particular slow-fast structure, we derive conditions under which there exists a low-dimensional attracting invariant manifold. The flow on this invariant manifold is described by a system of ODEs. Mode approximations of that system are studied by means of bifurcation theory and numerical tools. 相似文献
866.
Our main object in this paper is to discuss some results on rings with left identity in which certain subsets satisfy some functional identities. 相似文献
867.
V. Klepko S. Ryabov Yu. Kercha L. Bulavin R. Bila V. Slisenko O. Vasilkevich V. Krotenko 《Journal of Molecular Liquids》2005,120(1-3):67-69
Water molecule mobility in ion-containing and nonionic aqueous solutions of β-cyclodextrin was studied by quasielastic neutron scattering (QENS). The total self-diffusion coefficients and their components corresponding to the contributions from collective (Lagrange type) and single-particle (jump diffusion) parts of molecular motions were determined. From the data obtained, one can conclude that the molecular mobility of free water in nonionic aqueous solutions of β-cyclodextrin with guest molecules (2-aminopyridine) proceeds by a single-particle mechanism. The addition of Pb2+ ions into the solution leads to increase in self-diffusion coefficients and growth of a bound water fraction. 相似文献
868.
A set of invariants describing the limit regimes of braking disk-type wound composite flywheels is suggested. The limit regime is determined by using a linear failure criterion. It is shown that, for generating short-time impulses of very high power, a set of small identical flywheels is more effective than one large flywheel with an equivalent mass. Particular examples illustrating the theory considered are discussed. 相似文献
869.
R. Quintanilla 《Applied mathematics and computation》2004,150(3):661-668
This paper concerns a continuum theory of porous media saturated by multiple immiscible fluids. The case of a porous media saturated by two immiscible fluid proposes some new mathematical difficulties. We study the exponential stability of the one-dimensional problem when the nonwetting fluid is trapped in the wetting fluid and the exponential stability of the anti-plane shear deformations when the two fluids saturate the elastic media. 相似文献
870.