Variational iteration method for solving Fokker-Planck equation

In this paper variational iteration method is implemented to solve linear and nonlinear Fokker-Planck equations, and some similar equations. To illustrate the simplicity and reliability of the method some examples are provided and comparisons are made between the variational iteration method and the Adomian decomposition method. Comparison shows that variational iteration method is more effective and convenient to use and overcomes the difficulty arising in calculating Adomian polynomials. Also, this method can successfully be applied to a large class of problems.     

A matrix method for solving high-order linear difference equations with mixed argument using hybrid legendre and taylor polynomials

A numerical method for solving the higher order linear difference equations with variable coefficients and mixed argument under the mixed conditions is presented. The method is based on the hybrid Legendre and Taylor polynomials. The solution is obtained in terms of Legendre polynomials. IIIustrative examples are included to demonstrate the validity and applicability of the technique.     

MINRES法和有限元法解奇摄动反应扩散方程

讨论奇摄动反应扩散方程 的数值逼近求解问题, 及 均为正实数. 利用有限元方法并结合最小残量法, 给出求解该问题的一个新方 法, 该方法修正了单纯采用有限元方法求解时在边界附近呈现出的非正常扰动的 现象, 避免了因为 过小所引起的解的变异, 从而得到更加精确的数值结果.     

The IS–business relationship and its implications for performance: An empirical study of South African and Australian organisations

Lack of a close ‘Information systems (IS)–business relationship’ has been described as a potential inhibitor to improving the contribution that information systems (IS) make to business performance. Yet the value of specific attributes of an enduring relationship between IS and business remains to be demonstrated by empirically confirming their link to IS performance. Using data collected from 167 South African and Australian companies, this study examined the effect of three relational attributes, namely commitment, mutual understanding and shared vision, on the contribution of IS to business performance. The study also examines the interrelationship amongst the relational attributes. Results revealed that a strong IS–business relationship is a significant determinant of IS performance. Organisations more successful in their use of IS are characterised by strong commitment on the part of the business to IS efforts, higher levels of IS understanding of the business, and a long-term agreement, between business and IS executives, on IS priorities. Results have important implications for organisations looking to improve the contribution of IS to organisational performance.     

对计算水平分层介质响应正交归一化法的改进

汪荣江提出一个简单的正交归一化技术来克服经典的Thomson-Haskell传播矩阵方法中存在的数值不稳定问题.为了进一步提高计算效率,给出该方法的2种改进.一种改进方法是将传播矩阵中与频率无关的部分分离出来,对于某一固定的水平慢度,这些矩阵只需计算一次;另一个改进是利用Langer块对角化的技术,将传播矩阵分解为几个稀疏矩阵的乘积.我们将改进之后的算法应用于计算水平分层模型中的广义反射系数.较之原有方案,提出的改进能节省一半计算时间.