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71.
In this paperwewill derive a generalized uncertainty principle (GUP) in a simple varying speed of light (VSL) model. First
we will show that VSL is an immediate consequence of GUP. Then, within the framework of a simple VSL model, we will show that
GUP can be expressed as a function of cosmological scale factor. This expression gives two main results: uncertainties in
position and momentum are actually cosmological models dependent and these uncertainties depend on mass and momentum of the
particle under consideration. The relationship between matter content of the Universe and the values of uncertainties in early
stages of the evolution of the Universe will be discussed in a mini-superspace approach. 相似文献
72.
Existence and asymptotic stability for evolution problems on manifolds with damping and source terms
Marcelo M. Cavalcanti Valéria N. Domingos Cavalcanti 《Journal of Mathematical Analysis and Applications》2004,291(1):109-127
One considers the nonlinear evolution equation with source and damping terms
73.
ShaoJiFENG DeXingFENG 《数学学报(英文版)》2004,20(6):1057-1072
For wave equations with variable coefficients on regions which are not necessarily smooth, we study the energy decay rate when a nonlinear damping is applied on a suitable subrigion. 相似文献
74.
75.
In this article, a Timoshenko beam with tip body and boundary damping is considered. A linearized three-level difference scheme of the Timoshenko beam equations on uniform meshes is derived by the method of reduction of order. The unique solvability, unconditional stability and convergence of the difference scheme are proved. The convergence order in maximum norm is of order two in both space and time. A numerical example is presented to demonstrate the theoretical results. 相似文献
76.
K. Jagadeeswara Pillai S. Vijaya Kumar Varma M. Syam Babu 《Proceedings Mathematical Sciences》1987,96(1):61-69
The aligned magnetic effects on a steady laminar, viscous, incompressible, conducting fluid down an open inclined channel
bounded below by a bed of varying permeability has been studied when the free surface is exposed to atmospheric pressure.
Beavers and Joseph slip condition at the interface of the free flow region and the fluid flow in the porous bed and the Darcy’s
law in the porous medium have been used. The expressions for velocity, magnetic strength and the mass flow across the cross-section
of the channel are obtained. 相似文献
77.
In 1952 Darling proved the limit theorem for the sums of independent identically distributed random variables without power moments under the functional normalization. This paper contains an alternative proof of Darling’s theorem, using the Laplace transform. Moreover, the asymptotic behavior of probabilities of large deviations is studied in the pattern under consideration. 相似文献
78.
It is the purpose of this paper to model the retailer’s profit-maximizing strategy when confronted with supplier’s trade offer of credit and price-discount on the purchase of merchandise. Generally, retailers have to face many types of demands for different kinds of goods. In real situation, retailers have to correlate between the selling price and supplier’s trade offer, keeping in mind profit-maximization strategy. In the proposed model, all increasing deterministic demands are discussed analytically, numerically and graphically in the environment of permissible delay in payment and discount offer to the retailer. 相似文献
79.
80.
This paper considers the exponential decay of the solution to a damped semilinear wave equation with variable coefficients in the principal part by Riemannian multiplier method. A differential geometric condition that ensures the exponential decay is obtained. 相似文献