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991.
在(λ,μ)-模糊子群的基础上,进一步刻画了(λ,μ)-模糊子环和理想.详细讨论了(λ,μ)-模糊子环和理想的性质,以及它们与截集的关系,给出了相应结论. 相似文献
992.
令n是一个正整数,[n]={1,2,…,n}.利用集合[叫上的s-子集族((ns))构作了二元(p,r,d)-叠加码,研究了它的容错和析取性质并介绍了它在非适应性群测(Nonadaptive Group Testing)方面的应用. 相似文献
993.
Brownian motion and normal distribution have been widely used
in Cox-Ingersoll-Ross interest rate framework to model the instantaneous interest rate
dynamics. However, empirical studies have also shown that the return distribution of
interest rate has a higher peak and two fatter tails than those of the normal distribution.
Meanwhile, when the rare catastrophic shocks occur or the regime shifts in the economy
and finance, the money market may have jumps. In this paper, we will consider a class
of reflected Cox-Ingersoll-Ross interest rate models with noise. Furthermore,
we shall continue to supply the Laplace transform of the stationary distribution about
this reflected diffusion process with jumps. 相似文献
994.
995.
Periodicity and non‐negativity of solutions for nonlinear neutral differential equations with variable delay via fixed point theorems 下载免费PDF全文
Mouataz Billah Mesmouli Abdelouaheb Ardjouni Ahcene Djoudi 《Mathematical Methods in the Applied Sciences》2016,39(11):2840-2852
We use a modification of Krasnoselskii's fixed point theorem introduced by Burton to show the periodicity and non‐negativity of solutions for the nonlinear neutral differential equation with variable delay We invert this equation to construct the sum of a compact map and a large contraction, which is suitable for applying the modification of Krasnoselskii's theorem. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
996.
Global stability of a discrete virus dynamics model with Holling type‐II infection function 下载免费PDF全文
In this paper, we propose a discrete virus dynamics model with Holling type‐II infection function. By constructing Lyapunov function, we prove that if , then the infection‐free equilibrium is globally asymptotically stable; whereas if , then sufficient conditions are established for global stability of the infection equilibrium. Our results generalize some known results studied by other researchers. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
997.
Melike Kaplan Ömer Ünsal Ahmet Bekir 《Mathematical Methods in the Applied Sciences》2016,39(8):2093-2099
The (G′/G,1/G)‐expansion method and (1/G′)‐expansion method are interesting approaches to find new and more general exact solutions to the nonlinear evolution equations. In this paper, these methods are applied to construct new exact travelling wave solutions of nonlinear Schrödinger equation. The travelling wave solutions are expressed by hyperbolic functions, trigonometric functions and rational functions. It is shown that the proposed methods provide a powerful mathematical tool for solving nonlinear wave equations in mathematical physics and engineering. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
998.
In this paper,we study the scattering and blow-up dichotomy result of the radial solution to nonlinear Schrodinger equation(NLS) with the combined terms iu_t+△u=-|u|~4u+|4|~(p-1)u,1+4/3p5 in energy space H~1(R~3).The threshold energy is the energy of the ground state W of the focusing,energy critical NLS,which means that the subcritical perturbation does not affect the determination of threshold,but affects the scattering and blow-up dichotomy result with subcritical threshold energy.This extends algebraic perturbation in a previous work of Miao,Xu and Zhao[Comm.Math.Phys.,318,767-808(2013)]to all mass supercritical,energy subcritical perturbation. 相似文献
999.
1000.
Chin-Cheng Lin 《分析论及其应用》2008,24(4):336-350
In this paper the classical Besov spaces Bsp.q and Triebel-Lizorkin spaces Fsp.q for s ∈R are generalized in an isotropy way with the smoothness weights {|2j|aln}∞j=0. These generalized Besov spaces and Triebel-Lizorkin spaces, denoted by Bap.q and Fap.q for a ∈Irk and k ∈N, respectively, keep many interesting properties, such as embedding theorems (with scales property for all smoothness weights), lifting properties for all parameters a, and duality for index 0 < p < ∞. By constructing an example, it is shown that there are infinitely many generalized Besov spaces and generalized Triebel-Lizorkin spaces lying between Bs,p.q and ∪tsBt,p.q,and between Fsp.q and ∪ts Ftp.q, respectively. Between Bs,p,q and ∪tsBt,p.qq,and between Fsp,qand ∪tsFtp.q,respectively. 相似文献