共查询到20条相似文献,搜索用时 46 毫秒
1.
H.D. Voulov 《Journal of Difference Equations and Applications》2013,19(9):799-810
We consider positive solutions of the following difference equation x n =max A x n m k , B x n m m , n =0,1,…, where A , B are any positive real numbers and k , m are any positive integers. We prove that every positive solution is eventually periodic and determine the period in terms of the parameters A , B , k , and m . 相似文献
2.
Stevo Stević 《Journal of Difference Equations and Applications》2013,19(7):641-647
In this note we improve Theorem 2 in Ref. [3] , about the difference equation x n +1 = ~ i =0 k f i x n m i p i , n =0,1,2,..., where k is a positive integer, f i , p i ] (0, X ) for i =0,..., k , and the initial conditions x m k , x m k +1 ,..., x 0 are arbitrary positive numbers. 相似文献
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Alexei V. Bourd 《Journal of Difference Equations and Applications》2013,19(2):211-225
We investigate the asymptotic behavior of solutions of the system x ( n +1)=[ A + B ( n ) V ( n )+ R ( n )] x ( n ), n S n 0 , where A is an invertible m 2 m matrix with real eigenvalues, B ( n )= ~ j =1 r B j e i u j n , u j are real and u j p ~ (1+2 M ) for any M ] Z , B j are constant m 2 m matrices, the matrix V ( n ) satisfies V ( n ) M 0 as n M X , ~ n =0 X Á V ( n +1) m V ( n ) Á < X , ~ n =0 X Á V ( n ) Á 2 < X , and ~ n =0 X Á R ( n ) Á < X . If AV ( n )= V ( n ) A , then we show that the original system is asymptotically equivalent to a system x ( n +1)=[ A + B 0 V ( n )+ R 1 ( n )] x ( n ), where B 0 is a constant matrix and ~ n =0 X Á R 1 ( n ) Á < X . From this, it is possible to deduce the asymptotic behavior of solutions as n M X . We illustrate our method by investigating the asymptotic behavior of solutions of x 1 ( n +2) m 2(cos f 1 ) x 1 ( n +1)+ x 1 ( n )+ a sin n f n g x 2 ( n )=0 x 2 ( n +2) m 2(cos f 2 ) x 2 ( n +1)+ x 2 ( n )+ b sin n f n g x 1 ( n )=0 , where 0< f 1 , f 2 < ~ , 1/2< g h 1, f 1 p f 2 , and 0< f <2 ~ . 相似文献
5.
Ravi P. Agarwal Wan-Tong Li P.Y.H. Pang 《Journal of Difference Equations and Applications》2013,19(8):719-728
In this paper, we shall study the asymptotic behavior of solutions of difference equations of the form x n +1 = x n p f ( x n m k 1 , x n m k 2 ,…, x n m k r ), n =0,1,…, where p is a positive constant and k 1 ,…, k r are (fixed) nonnegative integers. In particular, permanence and global attractivity will be discussed. 相似文献
6.
William F. Trench 《Journal of Difference Equations and Applications》2013,19(9):811-821
We consider the functional difference system ( A ) j x i ( n )= f i ( n ; X ), 1 h i h k , where X =( x 1 ,…, x k ) and f 1 (·; X ),…, f k (·; X ) are real-valued functionals of X , which may depend quite arbitrarily on values of X ( l ) for multiple values of l ] Z . We give sufficient conditions for ( A ) to have solutions that approach specified constant vectors as n M X . Some of the results guarantee only that the solutions are defined for n sufficiently large, while others are global. The proof of the main theorem is based on the Schauder-Tychonoff theorem. Applications to specific quasi-linear systems are included. 相似文献
7.
A General Comparison Result for Higher Order Nonlinear Difference Equations With Deviating Arguments
John R. Graef Agnes Miciano-Cariño Chuanxi Qian 《Journal of Difference Equations and Applications》2013,19(11):1033-1052
The authors consider m -th order nonlinear difference equations of the form D m p x n + i h j ( n , x s j ( n ) )=0, j =1,2,( E j ) where m S 1, n ] N 0 ={0,1,2,…}, D 0 p x n = x n , D i p x n = p n i j ( D i m 1 p x n ), i =1,2,…, m , j x n = x n +1 m x n , { p n 1 },…,{ p n m } are real sequences, p n i >0, and p n m L 1. In Eq. ( E 1 ) , p = a and p n i = a n i , and in Eq. ( E 2 ) , p = A and p n i = A n i , i =1,2,…, m . Here, { s j ( n )} are sequences of nonnegative integers with s j ( n ) M X as n M X , and h j : N 0 2 R M R is continuous with uh j ( n , u )>0 for u p 0. They prove a comparison result on the oscillation of solutions and the asymptotic behavior of nonoscillatory solutions of Eq. ( E j ) for j =1,2. Examples illustrating the results are also included. 相似文献
8.
In this paper we consider the difference equation $$x_{n + 1} = \frac{{a + bx_{n - k} - cx_{n - m} }}{{1 + g(x_{n - 1} )}},$$ wherea, b, c are nonegative real numbers,k, l, m are nonnegative integers andg(x) is a nonegative real function. The oscillatory and periodic character, the boundedness and the stability of positive solutions of the equation is investigated. The existence and nonexistence of two-period positive solutions are investigated in details. In the last section of the paper we consider a generalization of the equation. 相似文献
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F. Merdivenci Atici Alberto Cabada Juan B. Ferreiro 《Journal of Difference Equations and Applications》2013,19(4):357-370
In this paper, we establish comparison results (maximum principles) which allow us to use the monotone method and the method of upper and lower solutions in order to build convergent sequences to the solutions of difference equations of the type j u k = f k , u k +1 , max l ] { k m h +1,…, k +1} u l , k ] I , u 0 = u T , with j u k = u k +1 m u k , I ={0,1,…, T m 1} and f ] C ( I 2 R 2 R , R ). 相似文献
10.
Peter Y. H. Pang Hongyan Tang Youde Wang 《Calculus of Variations and Partial Differential Equations》2006,26(2):137-169
In this paper, we study blow-up solutions to the Cauchy problem of the inhomogeneous nonlinear Schrödinger equation $ \partial_t u = i ( f(x) \Delta u + \nabla f(x) \cdot \nabla u +k(x)|u|^2u) $ on ${\mathbb{R}}^2In this paper, we study blow-up solutions to the Cauchy problem of the inhomogeneous nonlinear Schr?dinger equation
on
. We present existence and non-existence results and investigate qualitative properties of the solutions when they exist.
Mathematics Subject Classification (2000) 35Q55, 35G25
Dedicated respectfully to Professor Weiyue Ding on the occasion of his sixtieth birthday. 相似文献
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本文研究退化时滞差分系统Ex(k+ 1)= Ax(k)+ ∑li= 1Bix(k- i)+ f(k) (k= 0,1,2,…),x(k)= φ(k) (k= 0,- 1,- 2,…,- l),其中E、A、Bi∈Rm ×n,x(k)∈Rn,f(k)∈Rm ,rank(E)< n.给出了上述系统解的存在性条件及通解表达式. 相似文献
13.
Stefan Siegmund 《Journal of Difference Equations and Applications》2013,19(2):177-189
A linear autonomous system of difference equations x k +1 = Ax k can be transformed to its Jordan normal form, i.e. , the transformed system is in block diagonal form and the blocks correspond to different eigenvalues. We generalize this result to arbitrary nonautonomous linear systems x k +1 = A k x k with invertible matrices A k ] Â N 2 N , k ] { … , m 1, 0,1, … }. 相似文献
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Mohamed M. El‐Dessoky 《Mathematical Methods in the Applied Sciences》2017,40(3):535-545
The main objective of this paper was to study the global stability of the positive solutions and the periodic character of the difference equation where the parameters a , b , c , d , and e are positive real numbers and the initial conditions x ?t ,x ?t + 1,...,x ?1, x 0 are positive real numbers where t = m a x {l ,k ,s }. Some numerical examples will be given to explicate our results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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We offer sufficient conditions for the oscillation of all solutions of the partial difference equations y(m - 1,n) + β(m,n)y(m, n - 1) -δ(m,n)+ P(m,n,y(m + k,n + l)) = Q(m,n,y(m + k,n + l)) and (y(m - 1,n)+ β(m,n)y(m,n - 1) - δ(m,n)y(m,n) + $$\mathop \Sigma \limits_{i = 1}^\tau $$ Pi(m,ny(m + ki,n + li)) = $$\mathop \Sigma \limits_{i = 1}^\tau $$ Qi(m,n,y9m + ki,n + li)). Several examples which dwell upon the importance of our results are also included. 相似文献
16.
Xiangxing Tao & Yunpin Wu 《分析论及其应用》2012,28(3):224-231
In this paper,the authors prove that the multilinear fractional integral operator T A 1,A 2 ,α and the relevant maximal operator M A 1,A 2 ,α with rough kernel are both bounded from L p (1 p ∞) to L q and from L p to L n/(n α),∞ with power weight,respectively,where T A 1,A 2 ,α (f)(x)=R n R m 1 (A 1 ;x,y)R m 2 (A 2 ;x,y) | x y | n α +m 1 +m 2 2 (x y) f (y)dy and M A 1,A 2 ,α (f)(x)=sup r0 1 r n α +m 1 +m 2 2 | x y | r 2 ∏ i=1 R m i (A i ;x,y)(x y) f (y) | dy,and 0 α n, ∈ L s (S n 1) (s ≥ 1) is a homogeneous function of degree zero in R n,A i is a function defined on R n and R m i (A i ;x,y) denotes the m i t h remainder of Taylor series of A i at x about y.More precisely,R m i (A i ;x,y)=A i (x) ∑ | γ | m i 1 γ ! D γ A i (y)(x y) r,where D γ (A i) ∈ BMO(R n) for | γ |=m i 1(m i 1),i=1,2. 相似文献
17.
Messaoudi Abderrahim Errachid Mohammed Jbilou Khalide Sadok Hassane 《Numerical Algorithms》2019,80(1):253-278
Numerical Algorithms - Let x0,x1, ? , xn, be a set of n + 1 distinct real numbers (i.e., xm ≠ xj, for m ≠ j) and let ym,k, for m = 0, 1, ? , n, and k = 0, 1, ? , rm,... 相似文献
18.
The authors investigate the global behavior of the solutions of the difference equation xn+1=axn-1xn-k/bxn-p+cxn-q,n=0,1,…where the initial conditions x-r, x-r+1, x-r+2,… , x0 are arbitrary positive real numbers, r = max{l, k,p, q) is a nonnegative integer and a, b, c are positive constants. Some special cases of this equation are also studied in this paper. 相似文献
19.
设Ω=[-πxπ,-πyπ],C(Ω)表示关于x,y均以2π为周期的连续函数空间.若f(x,y)∈C(Ω),取结点组为(xk,yl)=(2k+2n 1)π,(2l 2+m 1)πk=0,1,2,…,2n,l=0,1,2,…,2m,则我们获得一个二元三角插值多项式Cn,m(f;x,y)=M1N∑k=2n0∑l=2m0f(xk,yl).1+2∑nα=1cosα(x-xk)+2∑mβ=1cosβ(y-yl)+4∑nα=1∑mβ=1cosα(x-xk)cosβ(y-yl)其中M=2m+1,N=2n+1.为改进其收敛性,本文构造一个新的因子ρα,β,使得带有该因子ρα,β的二元三角插值多项式Ln,m(f;x,y)可以在全平面上一致地收敛到每个连续的f(x,y),且具有最佳逼近阶. 相似文献
20.
R. K. S. Rathore 《Aequationes Mathematicae》1978,18(1-2):206-217
This note is a study of approximation of classes of functions and asymptotic simultaneous approximation of functions by theM n -operators of Meyer-König and Zeller which are defined by $$(M_n f)(x) = (1 - x)^{n + 1} \sum\limits_{k = 0}^\infty {f\left( {\frac{k}{{n + k}}} \right)} \left( \begin{array}{l} n + k \\ k \\ \end{array} \right)x^k , n = 1,2,....$$ Among other results it is proved that for 0<α≤1 $$\mathop {\lim }\limits_{n \to \infty } n^{\alpha /2} \mathop {\sup }\limits_{f \in Lip_1 \alpha } \left| {(M_n f)(x) - f(x)} \right| = \frac{{\Gamma \left( {\frac{{\alpha + 1}}{2}} \right)}}{{\pi ^{1/2} }}\left\{ {2x(1 - x)^2 } \right\}^{\alpha /2} $$ and if for a functionf, the derivativeD m+2 f exist at a pointx∈(0, 1), then $$\mathop {\lim }\limits_{n \to \infty } 2n[D^m (M_n f) - D^m f] = \Omega f,$$ where Ω is the linear differential operator given by $$\Omega = x(1 - x)^2 D^{m + 2} + m(3x - 1)(x - 1)D^{m + 1} + m(m - 1)(3x - 2)D^m + m(m - 1)(m - 2)D^{m - 1} .$$ 相似文献