基于算法随机排列的安全增强模型

数据安全是技术管理中的1个重要因素,为此出现了各种加密方法并广泛应用于保护敏感信息。加密方法都是以算法为基础,算法无论多么复杂,因其遵循固有的单调性,易受到暴力攻击的威胁。在选择加密算法时引入1个随机函数,提出1个集成的复合加密算法,它由经密钥选取的若干个算法组成;引入算法库的概念,定义算法的混合、层次排列加密机制。     

模糊随机环境下再利用逆向物流网络设计

考虑模糊随机环境下,再利用逆向物流网络在数量方面的不确定性,并考虑了回收点与回收中心的回收周期不同步等复杂因素,提出了第三方构建再利用逆向物流网络的数学模型。该模型结合遗传算法、模糊随机模拟及数学规划的混合智能算法,并通过算例验证模型和算法的可行性,得到模糊随机环境下的最优选址结果和回收点最优回收周期。     

Learning and behavioral stability An economic interpretation of genetic algorithms

This article tries to connect two separate strands of literature concerning genetic algorithms. On the one hand, extensive research took place in mathematics and closely related sciences in order to find out more about the properties of genetic algorithms as stochastic processes. On the other hand, recent economic literature uses genetic algorithms as a metaphor for social learning. This paper will face the question of what an economist can learn from the mathematical branch of research, especially concerning the convergence and stability properties of the genetic algorithm. It is shown that genetic algorithm learning is a compound of three different learning schemes. First, each particular scheme is analyzed. Then it is shown that it is the combination of the three schemes that gives genetic algorithm learning its special flair: A kind of stability somewhere in between asymptotic convergence and explosion.     

A simple example of complex dynamics

Summary. A discrete tatonnement process is analysed within the context of a two-person, two-good exchange economy where each person has a Cobb-Douglas utility function. This process is shown to exhibit period doubling bifurcation, topological and ergodic chaos. Received: June 22, 1998; revised version: July 15, 1998     

关联规则中支持度变化的数据重挖掘算法研究

使用关联规则进行数据挖掘时,使用者为了达到一定的挖掘效果,经常需要不断地改变关联规则的支持度阈值(support)。文中提出了一种从大型数据库中挖掘关联规则的快速算法。该算法以经典的Apriori算法为基础,可以在提出新的支持度后,直接在首次挖掘的基础上进行再一次挖掘。结果表明,它较Apriori算法的实现速度有明显的提高。     

基于家电回收的逆向物流网络模型研究

随着家电产品的增加,废旧家电产品的回收成为一个迫切需要解决的问题。在分析逆向物流网络模型的基础上,根据家电产品的特征,提出了家电回收的逆向物流网络模型;它包括了收集点、检测点、再制造工厂、最终处理点、产品分销中心和销售点。并运用遗传算法,以运输成本最小为目标,对家电产品回收的逆向物流网络的设施进行选址优化。最后,给出一个应用实例。     

基于欠采样的混沌保密通信系统的保密性分析

近年来,环境壁垒已经成为国际贸易领域中对自由贸易妨碍程度最深的一种贸易壁垒。来自外贸统计数据表明,环境壁垒已经对中国的农产品出口造成了极为不利的影响。本文旨在研究中国的农产品出口屡遭发达国家环境壁垒阻挠的原因以及在WTO框架下包括中国在内的发展中国家该如何正视环境壁垒的双重性、如何采取措施来规避环境壁垒、解决由环境壁垒引发的贸易争端进而合法地利用环境壁垒来保护本国的环境和人类与动植物的健康。     

电子商务中的安全技术

系统介绍了电子商务采用的对称加密、非对称加密的加密技术 ;基于数字信封、数字证书、数字签名的网络信息安全传输技术 ;SSL ,SET两种主要协议和 CA中心的应用。并对 EDI的安全进行了描述。结合国内情况提出了安全地开展电子商务的相关事宜     

Multi-objective optimization for planning liner shipping service with uncertain port times

This paper considers a joint tactical planning problem for the number of ships, the planned maximum sailing speed, and the liner service schedule in order to simultaneously optimize the expected cost, the service reliability and the shipping emission in the presence of port time uncertainty. The problem is formulated into a stochastic multi-objective optimization problem at the operational level. The relationships between the objectives and the decision variables are established. A simulation-based non-dominated sorting genetic algorithm is then presented to solve this problem. A case study is provided to illustrate the results and the application of the model.     

The congested multicommodity network design problem

This paper studies a version of the fixed-charge multicommodity network design problem where in addition to the traditional costs of flow and design, congestion at nodes is explicitly considered. The problem is initially modeled as a nonlinear integer programming formulation and two solution approaches are proposed: (i) a reformulation of the problem as a mixed integer second order cone program to optimally solve the problem for small to medium scale problem instances, and (ii) an evolutionary algorithm using elements of iterated local search and scatter search to provide upper bounds. Extensive computational results on new benchmark problem instances and on real case data are presented.