三参量速度分析的迭代算法

采用预求倾角法进行三参量速度分析时，首先要确定地下界面的倾向和倾角。若没有准确速度，就求不准倾向和倾角，因此无法一次求得准确的结果。若采用迭代算法，则可以使三参量逐渐向精确值逼近。在地层倾角小于４５＾０的情况下，迭代是收敛的。在有噪音的情况下，噪音会使叠加道集上同相轴的时间发生变化，从而影响倾向的确定，因此在迭代的每一步，都必须估算倾向。理论实际资料的试算表明，采用迭代方法求取地下界面参数是切实可     

实际化工模拟过程有效切割算法的研究

根据化工模拟计算中复杂循环回路的理论切割准则,讨论了如何使用图论及回路搜索的方法得出一种理论性的回路切割算法。在此基础上,又研究了实际应用过程中不适用图论切割原理的一些化工过程,给出了相应的处理方法,使该原理能够真正应用到实际流程中。     

THE ANALYSIS OF THE SEPARATED LAYERS ALGORITHM BY DOMAIN DECOMPOSITION METHOD

From the principle of of the Domain Decomposition Method (DDM), we analyse the 2nd-order linear elliptic partial differential problems and link the Separated-Layers Algorithm (SLA) with DDM. The mathematical properties of SLA and numerical example are presented to obtain satisfactory computation results. For general linear differential ones, also are the structure of SLA and its characteristics discussed.     

基于整体轮换杂交的改进遗传算法

针对遗传算法的过早收敛问题,提出了一种新的解决方法———整体轮换杂交法,对其作用进行了讨论。对基于该法的改进遗传算法进行了实验并与其它算法进行了比较。结果表明整体轮换杂交法可以更有效地防止遗传算法过早收敛。     

Binary-coding-based ant colony optimization and its convergence

Ant colony optimization (ACO for short) is a meta-heuristics for hard combinatorial optimization problems. It is a population-based approach that uses exploitation of positive feedback as well as greedy search. In this paper, genetic algorithm's (GA for short) ideas are introduced into ACO to present a new binary-coding based ant colony optimization. Compared with the typical ACO, the algorithm is intended to replace the problem's parameter-space with coding-space, which links ACO with GA so that the fruits of GA can be applied to ACO directly. Furthermore, it can not only solve general combinatorial optimization problems, but also other problems such as function optimization. Based on the algorithm, it is proved that if the pheromone remainder factor ρ is under the condition of ρ≥1, the algorithm can promise to converge at the optimal, whereas if 0<ρ<1, it does not. This work is supported by the Science Foundation of Shanghai Municipal Commission of Science and Technology under Grant No.00JC14052. Tian-Ming Bu received the M.S. degree in computer software and theory from Shanghai University, China, in 2003. And now he is a Ph.D. candidate of Fudan University in the same area of theory computer science. His research interests include algorithms, especially, heuristic algorithms and heuristic algorithms and parallel algorithms, quantum computing and computational complexity. Song-Nian Yu received the B.S. degree in mathematics from Xi'an University of Science and Technology, Xi'an, China, in 1981, the Ph.D. degree under Prof. L. Lovasz's guidance and from Lorand University, Budapest, Hungary, in 1990. Dr. Yu is a professor in the School of Computer Engineering and Science at Shanghai University. He was a visiting professor as a faculty member in Department of Computer Science at Nelson College of Engineering, West Virginia University, from 1998 to 1999. His current research interests include parallel algorithms' design and analyses, graph theory, combinatorial optimization, wavelet analyses, and grid computing. Hui-Wei Guan received the B.S. degree in electronic engineering from Shanghai University, China, in 1982, the M.S. degree in computer engineering from China Textile University, China, in 1989, and the Ph.D. degree in computer science and engineering from Shanghai Jiaotong University, China, in 1993. He is an associate professor in the Department of Computer Science at North Shore Community College, USA. He is a member of IEEE. His current research interests are parallel and distributed computing, high performance computing, distributed database, massively parallel processing system, and intelligent control.     

基于改进基因表达式程序设计的股票指数预测

介绍基因表达式程序设计方法的基本原理,针对股票指数分析与预测问题,在经典的GEP算法基础上,提出一种基于动态变异算子的改进的GEP算法——IGEP算法,动态变异算子随着进化代数和染色体所含基因数目不同而变化,从而加快了GEP的收敛速度和精确度,对算法进行了复杂度和收敛性分析。设计一种基于IGEP的股票指数分析与预测算法,数值实验结果表明,该算法优于经典GEP算法,具有较广泛的通用性。     

On the relation between entropy and the average complexity of trajectories in dynamical systems

If (X,T) is a measure-preserving system, a nontrivial partition of X into two sets and f a positive increasing function defined on the positive real numbers, then the limit inferior of the sequence is greater than or equal to the limit inferior of the sequence of quotients of the average complexity of trajectories of length n generated by and nf(log₂(n))/log₂(n). A similar statement also holds for the limit superior. Received: August 20, 1999.     

An asymptotic estimate of the error of eigenvalues in the method of finite elements for the sturm-liouville problem

A scheme of the second order of accuracy for the Sturm—Liouville problem is constructed by the method of finite elements with the use of a special basic system of compact functions. The convergence of the method of finite elements is proved. An exact formula for estimating errors of eigenvalues is obtained. Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 28–36, March–Apni, 2000.     

改进型遗传算法及其在数据挖掘中的应用

文中在简单遗传算法的基础上,利用改进的算法进行关联规则的发现和数据库中特征项权重的发现,通过对农业气象数据库的实验,力求解决遗传算法中的早熟等问题。     

A homotopy analysis method for the nonlinear partial differential equations arising in engineering

In this article, we have established the homotopy analysis method (HAM) for solving a few partial differential equations arising in engineering. This technique provides the solutions in rapid convergence series with computable terms for the problems with high degree of nonlinear terms appearing in the governing differential equations. The convergence analysis of the proposed method is also discussed. Finally, we have given some illustrative examples to demonstrate the validity and applicability of the proposed method.