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OSCILLATORY BEHAVIOR OF SOLUTIONS OF CERTAIN THIRD ORDER MIXED NEUTRAL DIFFERENCE EQUATIONS 被引量:1
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作者 E.THANDAPANI N.KAVITHA 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期218-226,共9页
The objective of this paper is to study the oscillatory and asymptotic properties of the mixed type third order neutral difference equation of the form△(an△^2(xn+bnxn-τ1+cnxn+τ2))+qnx^βn+1-σ1+pnx^^βn... The objective of this paper is to study the oscillatory and asymptotic properties of the mixed type third order neutral difference equation of the form△(an△^2(xn+bnxn-τ1+cnxn+τ2))+qnx^βn+1-σ1+pnx^^βn+1+σ2=0,where (an), (bn}, (cn}, (qn} and (pn} are positive real sequences, β is a ratio of odd positive integers, τ1, τ2, and σ2 are positive integers. We establish some sufficient conditions which ensure that all solutions are either oscillatory or converges to zero. Some examples are presented to illustrate the main results. 展开更多
关键词 OSCILLATION third order mixed type neutral difference equation
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Oscillatory and Asymptotic Behavior of Solutions of Second Order Neutral Delay Difference Equations with “Maxima”
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作者 Ramalingam Arul Manvel Angayarkanni 《Advances in Pure Mathematics》 2015年第2期71-81,共11页
In this paper, we study the oscillatory and asymptotic behavior of second order neutral delay difference equation with “maxima” of the form? Examples are given to illustrate the main result.
关键词 Second order OSCILLATORY ASYMPTOTIC Behavior neutral Delay difference equationS with “Maxima”
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Solution of a One-Dimension Heat Equation Using Higher-Order Finite Difference Methods and Their Stability
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作者 M. Emran Ali Wahida Zaman Loskor +1 位作者 Samia Taher Farjana Bilkis 《Journal of Applied Mathematics and Physics》 2022年第3期877-886,共10页
One-dimensional heat equation was solved for different higher-order finite difference schemes, namely, forward time and fourth-order centered space explicit method, backward time and fourth-order centered space implic... One-dimensional heat equation was solved for different higher-order finite difference schemes, namely, forward time and fourth-order centered space explicit method, backward time and fourth-order centered space implicit method, and fourth-order implicit Crank-Nicolson finite difference method. Higher-order schemes have complexity in computing values at the neighboring points to the boundaries. It is required there a specification of the values of field variables at some points exterior to the domain. The complexity was incorporated using Hicks approximation. The convergence and stability analysis was also computed for those higher-order finite difference explicit and implicit methods in case of solving a one dimensional heat equation. The obtained numerical results were compared with exact solutions. It is found that backward time and fourth-order centered space implicit scheme along with Hicks approximation performed well over the other mentioned higher-order approaches. 展开更多
关键词 Heat equation Boundary Condition higher-order Finite difference Methods Hicks Approximation
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Numerical storm surge model with higher order finite difference method of lines for the coast of Bangladesh 被引量:2
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作者 Gour Chandra Paul Md. Emran Ali 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第6期100-116,共17页
In this study, the method of lines (MOLs) with higher order central difference approximation method coupled with the classical fourth order Runge-Kutta (RK(4,4)) method is used in solving shallow water equations (SWEs... In this study, the method of lines (MOLs) with higher order central difference approximation method coupled with the classical fourth order Runge-Kutta (RK(4,4)) method is used in solving shallow water equations (SWEs) in Cartesian coordinates to foresee water levels associated with a storm accurately along the coast of Bangladesh. In doing so, the partial derivatives of the SWEs with respect to the space variables were discretized with 5-point central difference, as a test case, to obtain a system of ordinary differential equations with time as an independent variable for every spatial grid point, which with initial conditions were solved by the RK(4,4) method. The complex land-sea interface and bottom topographic details were incorporated closely using nested schemes. The coastal and island boundaries were rectangularized through proper stair step representation, and the storing positions of the scalar and momentum variables were specified according to the rules of structured C-grid. A stable tidal regime was made over the model domain considering the effect of the major tidal constituent, M2 along the southern open boundary of the outermost parent scheme. The Meghna River fresh water discharge was taken into account for the inner most child scheme. To take into account the dynamic interaction of tide and surge, the generated tidal regime was introduced as the initial state of the sea, and the surge was then made to come over it through computer simulation. Numerical experiments were performed with the cyclone April 1991 to simulate water levels due to tide, surge, and their interaction at different stations along the coast of Bangladesh. Our computed results were found to compare reasonable well with the limited observed data obtained from Bangladesh Inland Water Transport Authority (BIWTA) and were found to be better in comparison with the results obtained through the regular finite difference method and the 3-point central difference MOLs coupled with the RK(4,4) method with regard to the root mean square error values. 展开更多
关键词 SHALLOW water equations METHOD of lines higher order finite difference approximation METHOD SURGE nested scheme
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CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS 被引量:3
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作者 丁小丽 Juan J.NIETO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1003-1013,共11页
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex... Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results. 展开更多
关键词 CONTROLLABILITY OPTIMALITY neutral equations different fractional orders
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PERMANENCE AND ASYMPTOTIC PROPERTIES OF NONLINEAR DELAY DIFFERENCE EQUATIONS
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作者 李万同 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第11期1273-1280,共8页
The asymptotic behavior of a class of nonlinear delay difference equation wax studied . Some sufficient conditions are obtained for permanence and global attractivity . The results can be applied to a claxs of nonline... The asymptotic behavior of a class of nonlinear delay difference equation wax studied . Some sufficient conditions are obtained for permanence and global attractivity . The results can be applied to a claxs of nonlinear delay difference equations and to the delay discrete Logistic model and some known results are included. 展开更多
关键词 global attractivity higher-order nonlinear difference equation PERMANENCE DELAY
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Existence of Nonoscillatory Solutions of a Class of Nonlinear Dynamic Equations with a Forced Term
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作者 Shanliang Zhu Xinli Zhang 《Open Journal of Discrete Mathematics》 2012年第4期173-178,共6页
In this paper, we consider the following forced higher-order nonlinear neutral dynamic equation on time scales. By using Banach contraction principle, we obtain sufficient conditions for the existence of nonoscillator... In this paper, we consider the following forced higher-order nonlinear neutral dynamic equation on time scales. By using Banach contraction principle, we obtain sufficient conditions for the existence of nonoscillatory solutions for general and which means that we allow oscillatory and . We give some examples to illustrate the obtained results. 展开更多
关键词 Dynamic equation higher order NON-OSCILLATION Time SCALE neutral
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OSCILLATION CRITERIA FOR A CLASS OF HIGHER ORDER NEUTRAL DIFFERENTIAL EQUATIONS 被引量:3
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作者 欧阳自根 唐清干 《Annals of Differential Equations》 2003年第1期65-70,共6页
We establish a new oscillation condition for even order neutral type differential equation of the following formwhere f is continuous and exists 1 ≤ k ≤ m(?)(t) ≡ Tk(t), a, (?)i ∈ C([0, ∞], R), i = 1, …,m. such ... We establish a new oscillation condition for even order neutral type differential equation of the following formwhere f is continuous and exists 1 ≤ k ≤ m(?)(t) ≡ Tk(t), a, (?)i ∈ C([0, ∞], R), i = 1, …,m. such that 0 ≤ a(t) ≤ L and 展开更多
关键词 higher order neutral differential equation OSCILLATION eventually positive solution
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Oscillatory Behavior of Solutions of General Third Order Mixed Neutral Difference Equations 被引量:1
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作者 Bi-shan ZHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2015年第2期467-474,共8页
The objective of this paper is to study the oscillatory and asymptotic properties of the general mixed type third order neutral difference equation of the form △(aαn△2(xn+ bnxn-τ1+ cnxn+τ2)) + qnx^a n+1... The objective of this paper is to study the oscillatory and asymptotic properties of the general mixed type third order neutral difference equation of the form △(aαn△2(xn+ bnxn-τ1+ cnxn+τ2)) + qnx^a n+1-σ+ pnx^βn+1+=σ2 0,where {an}, {bn}, {cn}, {qn} and {pn} are positive real sequences, both α and β are ratios of odd positive integers, τ1, τ2, σ1 and σ2 are positive integers. We establish some sufficient conditions which ensure all solutions are either oscillatory or converge to zero. 展开更多
关键词 OSCILLATION third order general mixed type neutral difference equation
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ESTIMATES ON THE SOLUTIONS OF CERTAIN HIGHER ORDER FINITE DIFFERENCE EQUATIONS
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作者 B.G.Pachpatte 《Annals of Differential Equations》 1998年第4期583-590,共8页
In this paper results on the estimates for solutions of certain higher order finite difference equations are established. The main tool employed in our analysis is based on the applications of the discrete inequality ... In this paper results on the estimates for solutions of certain higher order finite difference equations are established. The main tool employed in our analysis is based on the applications of the discrete inequality which provides an explicit bound on the unknown function. 展开更多
关键词 estimates on the solutions higher order finite difference equations discrete inequality dependency of solutions
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OSCILLATION THEOREMS FOR SECOND ORDER NEUTRAL DIFFERENCE EQUATIONS
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作者 Jianmin Guo,Huiqin Chen,Shugui Kang(School of Math.and Computer Sciences,Shanxi Datong University,Datong 037008,Shanxi) 《Annals of Differential Equations》 2012年第3期259-262,共4页
The aim of this paper is to study the oscillation of second order neutral difference equations.Our results are based on the new comparison theorems,that reduce the problem of the oscillation of the second order equati... The aim of this paper is to study the oscillation of second order neutral difference equations.Our results are based on the new comparison theorems,that reduce the problem of the oscillation of the second order equation to that of the first order equation.The comparison principles obtained essentially simplify the examination of the equations. 展开更多
关键词 second order neutral difference equations comparison theorem OSCILLATION NONOSCILLATION
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基于RKADE-SS-FDTD方法的无条件稳定高阶CFS-PML算法
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作者 李建雄 魏之栋 《天津工业大学学报》 CAS 北大核心 2023年第2期55-60,共6页
为了提升完全匹配层(PML)算法的吸收效果,提出了一种用于截断非磁化等离子体的高阶复频率偏移PML(HO-CFS-PML)算法。该算法将龙格-库塔辅助微分方程(RKADE)算法和分裂步时域有限差分(SS-FDTD)算法相结合,来对非磁化等离子体进行仿真。... 为了提升完全匹配层(PML)算法的吸收效果,提出了一种用于截断非磁化等离子体的高阶复频率偏移PML(HO-CFS-PML)算法。该算法将龙格-库塔辅助微分方程(RKADE)算法和分裂步时域有限差分(SS-FDTD)算法相结合,来对非磁化等离子体进行仿真。在计算域边界处,引入了由辅助微分方程(ADE)算法实现的HO-CFS-PML用于截断开放区域中的等离子体,并通过一个数值算例进行模拟。结果表明:所提出的HO-RKADE-SS-CFS-PML算法在柯朗-弗里德里希斯-列维(CFL)数(CFLN)为8时,相比于传统CFS-PML算法,时间减少率可以达到79.2%,证明了该算法能够有效地消除柯朗-弗里德里希斯-列维(CFL)稳定性条件的约束,大大节省了计算时间;此外,HO-RKADE-SS-CFS-PML算法的最大相对反射误差可以达到-115 dB,明显小于其他算法的相对反射误差,并且随着CFLN的增大,该算法不会像RKADE-ADI-CFS-PML算法那样产生明显的误差增大现象,证明本文算法在大时间步长下拥有比其他算法更好的吸收电磁波的能力。 展开更多
关键词 高阶复频率偏移完全匹配层 分裂步时域有限差分法 龙格-库塔辅助微分方程 非磁化等离子体
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基于Taylor级数构造高阶差分格式的方法与应用研究
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作者 徐校会 孟红军 《哈尔滨师范大学自然科学学报》 CAS 2023年第5期21-27,共7页
有限差分方法常用于求解微分方程的数值解,而高阶差分格式在数值计算中有着非常重要的地位.Taylor级数的应用非常广泛,在数值微分中有着非常重要的作用,尤其是在获得截断误差的过程中.以3阶、4阶、6阶差分格式为例,给出了利用Taylor展... 有限差分方法常用于求解微分方程的数值解,而高阶差分格式在数值计算中有着非常重要的地位.Taylor级数的应用非常广泛,在数值微分中有着非常重要的作用,尤其是在获得截断误差的过程中.以3阶、4阶、6阶差分格式为例,给出了利用Taylor展开式构造对应差分格式的详细过程和一般高阶差分格式的构造方法.通过两个具体应用实例,利用高阶、低阶差分格式求解常微分方程的数值解,并对结果进行分析,验证高阶差分格式的高效性.结果表明,基于Taylor级数构造高阶差分格式的方法可行. 展开更多
关键词 TAYLOR级数 高阶差分格式 常微分方程 偏微分方程
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一类高阶中立型差分方程的正解存在性 被引量:12
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作者 王东华 钟晓珠 +2 位作者 梁景翠 郝璞玉 李宝风 《武汉理工大学学报》 EI CAS CSCD 北大核心 2006年第12期145-147,共3页
研究了一类具有正负系数的高阶中立型时滞差分方程解的正解存在性问题。利用Krasnoselskii不动点定理在阶为偶数时和阶为奇数的2种情形下,分别讨论了该时滞方程的最终正解的存在性及渐近性态,获得了该时滞方程正解存在性及其解趋于0的... 研究了一类具有正负系数的高阶中立型时滞差分方程解的正解存在性问题。利用Krasnoselskii不动点定理在阶为偶数时和阶为奇数的2种情形下,分别讨论了该时滞方程的最终正解的存在性及渐近性态,获得了该时滞方程正解存在性及其解趋于0的几个充分条件。 展开更多
关键词 中立型差分方程 正解 KRASNOSELSKII不动点定理 正负系数
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高阶中立型差分方程正解的存在性 被引量:5
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作者 杨建法 董文雷 刘玉军 《河北师范大学学报(自然科学版)》 CAS 2001年第3期284-286,295,共4页
讨论了奇数阶中立型差分方程正解的存在性,在允许中立项系数在1附近振动的条件下,利用在集合上定义映射和构造序列的方法,得出了方程存在正解的充分条件.
关键词 高阶中立型差分方程 正解 存在性 振动性 中立项系数 映射 构造序列
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高阶非线性中立型方程的振动定理 被引量:2
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作者 余秀萍 米玉珍 +1 位作者 王培光 杨红玉 《河北师范大学学报(自然科学版)》 CAS 2004年第5期439-442,共4页
研究了一类具有连续分布滞量的高阶非线性中立型方程a(t)ψ(x(t))[x(t)+∑mi=1ci(t)x(τi(t))](n-1)′+∫baf(t,ξ,x(g(t,ξ)))dσ(ξ)=0解的振动性,运用数学分析方法和技巧及方程各阶导数的符号关系,在2种不同情形下得到了该类方程新... 研究了一类具有连续分布滞量的高阶非线性中立型方程a(t)ψ(x(t))[x(t)+∑mi=1ci(t)x(τi(t))](n-1)′+∫baf(t,ξ,x(g(t,ξ)))dσ(ξ)=0解的振动性,运用数学分析方法和技巧及方程各阶导数的符号关系,在2种不同情形下得到了该类方程新的振动准则. 展开更多
关键词 高阶非线性中立型方程 振动定理 连续分布时滞 泛函微分方程 无界非振动解
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高阶中立型微分方程正解的存在性 被引量:4
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作者 唐先华 庾建设 《湖南大学学报(自然科学版)》 EI CAS CSCD 2000年第4期7-10,共4页
研究奇数阶中立型微分方程正解存在性 ,在允许中立项系数于1附近振动的情况下 ,获得了方程存在正解的充分条件 .本文结果部分地回答了 Gyori和 L adas所提出的一个公开问题 .
关键词 高阶中立型微分方程 正解 振动 存在性
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奇数阶中立型差分方程的线性化振动性定理 被引量:4
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作者 周展 庾建设 《应用数学》 CSCD 1999年第4期65-68,共4页
本文得到了奇数阶中立型差分方程的一个线性化振动性定理。
关键词 奇数阶 中立型差分方程 线性化振动性 差分方程
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具高阶Laplace算子的非线性脉冲中立抛物型方程的振动性 被引量:5
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作者 罗李平 杨柳 《工程数学学报》 CSCD 北大核心 2009年第4期663-670,共8页
本文研究一类具高阶Laplace算子的非线性脉冲中立型时滞抛物偏微分方程的振动性质,利用一阶脉冲时滞微分不等式,获得了该类方程在两类不同边值条件下所有解振动的若干充分性判据。所得结论将脉冲时滞微分方程的振动性质推广到脉冲中立... 本文研究一类具高阶Laplace算子的非线性脉冲中立型时滞抛物偏微分方程的振动性质,利用一阶脉冲时滞微分不等式,获得了该类方程在两类不同边值条件下所有解振动的若干充分性判据。所得结论将脉冲时滞微分方程的振动性质推广到脉冲中立型时滞偏微分方程,同时也反映了脉冲和时滞在振动中的影响作用。 展开更多
关键词 脉冲 非线性中立型 时滞 抛物型偏微分方程 振动 高阶LAPLACE算子
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一类高阶中立型微分方程解的振动性 被引量:4
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作者 王培光 王玉新 《河北大学学报(自然科学版)》 CAS 2001年第3期207-214,共8页
讨论了一类具有连续偏差变元的高阶中立型微分方程 ,运用分析方法和技巧 ,得到了该类方程解的振动准则 。
关键词 高阶中立型方程 连续偏差变元 振动性
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