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101.
R. Abo-Zeid 《Journal of Difference Equations and Applications》2018,24(2):220-239
In this paper, we solve open problem (5) submitted by Sedaghat in his paper, On third order rational difference equations with quadratic terms, J. Differ. Equ. Appl., 14(8) (2008), pp. 889–897. We also confirm conjecture (6) in the mentioned paper. 相似文献
102.
103.
M. Z. Abd-Alla H. A. Hassan H. A. Ayad 《Journal of Difference Equations and Applications》2018,24(8):1318-1345
This paper introduces sampling representations for discrete signals arising from self adjoint difference operators with mixed boundary conditions. The theory of linear operators on finite-dimensional inner product spaces is employed to study the second-order difference operators. We give necessary and sufficient conditions that make the operators self adjoint. The equivalence between the difference operator and a Hermitian Green's matrix is established. Sampling theorems are derived for discrete transforms associated with the difference operator. The results are exhibited via illustrative examples, involving sampling representations for the discrete Hartley transform. Families of discrete fractional Fourier-type transforms are introduced with an application to image encryption. 相似文献
104.
We consider a higher order rational difference equation. Firstly, we skillfully give a sufficient and necessary condition for the existence and uniqueness of the initial value problem. And then we investigate the local stability, asymptotic behavior, periodicity and oscillation of solutions for the difference equation. Finally, we give some numerical simulations to illustrate our results. 相似文献
105.
Existence and multiplicity of positive solutions for a system of difference equations with coupled boundary conditions
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We study the existence and multiplicity of positive solutions for a system of nonlinear second-order difference equations subject to coupled multi-point boundary conditions. 相似文献
106.
Jun Ji 《Journal of Mathematical Analysis and Applications》2010,367(2):409-415
We consider the following two classes of second order boundary value problems for difference equation:
107.
108.
In this paper we introduce a generalized vector-valued paranormed sequence space Np(Ek,Δm,f,s) using modulus function f, where p=(pk) is a bounded sequence of positive real numbers such that infkpk>0,(Ek,qk) is a sequence of seminormed spaces with Ek+1⊆Ek for each k ∈ N and s?0. We have also studied sequence space Np(Ek,Δm,fr,s), where fr=f°f°f°,…,f (r-times composition of f with itself) and r∈N={1,2,3,…}. Results regarding completeness, K-space, normality, inclusion relations etc. are derived. Further, a study of multiplier of the set Np(Ek,f,s) is also made by choosing (Ek,‖·‖k) as sequence of normed algebras. 相似文献
109.
In this paper, by using a quartic spline in space and generalized trapezoidal formula in time direction, one-dimensional telegraphic equations are solved. We present new classes of two-level schemes. The accuracy of these methods are O(k2+h4). It has been shown that by suitably choosing parameter, a high accuracy scheme of O(k3+h4) can be derived from our methods. Numerical results demonstrate the superiority of the new scheme. 相似文献