Interval programming model for risk-based partner selection of virtual enterprise

The problem of risk-based partner selection of virtual enterprise is investigated. By choosing optimal partner for each project task, the project risk is minimized. The risk parameters are expressed in the form of interval numbers when the precise values are difficult to obtain, and the model is formulated into a 0-1 nonlinear programming with interval coefficients in its objective function. In order to solve the problem, the definition of order relation between interval numbers is given, and the original model is converted into an equivalent crisp bi-objective programming model. Because of the highly constrained nature and multiple objective of the model, a genetic algorithm is proposed to find the set of Pareto or near Pareto optimal solutions. The approach is demonstrated by some numerical examples, and the result shows that the suggested approach has high efficiency and the model has potential to practical applications.     

基于IEEE802.11a的符号定时同步新方法

<正>张媛的“电子商务与税收新理念的探析”一文,在本刊2005年第6期发表后,本刊收到西南财经大学尹音频检举张文存在抄袭内容的来信。本刊立即展开调查工作,现将有关调查与处理情况公告如下: 1．经鉴定,张文大量甚至原封不动地抄袭了尹音频的“电子商务税收理念与     

The impact of market freedom on the adoption of third-party electronic marketplaces: A fuzzy AHP analysis

Electronic-marketplace (EM) is an innovative model for interfirm transactions that are undertaken via the Internet. However, in view of higher investment costs and other associated risks, many small and medium-sized enterprises (SMEs), instead of establishing their own EMs, turn to adopt third-party-hosted EMs. In literature, most relevant studies to the adoption of the third-party-hosted EM were conducted on the research contexts of free market. Industries under the protection of government policies may have limited degree of market freedom, different from industries without these protection policies. Thus, this study intends to compare the decision choice of EM adoption between industries with various degree of market freedom. The decision choice of EM adoption consisted of many strategic factors that were constructed in terms of a three-layer hierarchical structure proposed in this paper. A fuzzy analytic hierarchical process (Fuzzy AHP) was utilized to estimate the relative importance of these individual strategic factors involved in the decision-making process of adopting third-party EMs. The research findings indicated there were some similarities and differences in the decision choice between the two industries of interest. The variety of market freedom can account for the differences in the decision choice of EM adoption. In addition to enhancing our understanding of the EM adoption decision of participative companies, the research findings also provide insightful information to third-party EM providers so that they may improve the effectiveness and efficiency of resource allocation.     

初相注入式快速符号同步的一种实现方法

通过平方滤波算法对时钟初相进行预估计,实现了Gardner算法下初相注入式符号同步.该方法具有快速、高精度的特点,尤其是较好地解决了初始点为过零点的极端情况下,Gardner算法收敛方向不确定、收敛时间较长的问题.计算机仿真和实际应用证实了该方法的有效性.     

一种改进的非凸秩最小化算法及其在矩阵恢复中的应用

在分析现有处理矩阵恢复问题的非凸秩最小化算法的基础上,提出了一种基于超松弛迭代的改进算法,并给出了松弛因子ω的确定准则。仿真实验表明:在惩罚参数选取较大的情形下,改进算法较原算法具有更快的收敛速度及更高的收敛精度,同时展示了基于非凸秩最小化算法的矩阵恢复技术在图像去噪中的应用。     

基于ISM的可达矩阵的简便算法

解释结构模型化技术是最基本、最具特色的系统结构模型化技术,求可达矩阵又是建立递阶结构模型(ISM)中最重要的一步,本文基于ISM有向图,根据布尔代数运算规则,阐述一种更简便的由邻接矩阵求可达矩阵的新算法。本文与Warshall算法作对比,体现出该新算法的简便之处。该算法以后也可以实现计算机化。     

基于人工免疫算法的多无人机分布式任务分配方法

对多无人机任务分配问题进行了研究,在重量和路径负载均衡的基础上建立了带有攻击顺序的01决策变量的模型,运用分布式的人工免疫算法对该模型进行仿真实验,最终得到每个无人机攻击的目标顺序以及目标函数值,实验证明该方法在得到不劣于遗传算法结果的同时,提高了寻找最优解的收敛速度。     

QR二维码在开放大学身份验证系统中的应用研究

通过介绍QR二维码的基本知识及其特点,然后根据开放大学学生管理的特点,设计并实现了开放大学身份验证系统,重点介绍了系统设计中的关键技术。     

基于行业分布的企业网络信息安全威胁及对策研究

在互联网日益普及的今天,企业越来越重视自身的信息化建设,企业信息化的发展使得接入互联网的企业不断增长,如何保护企业信息安全成为企业发展的关键内容之一。本文采取数理统计及文本分类的方法,对来自某知名黑客论坛的300余万条数据进行分析,通过TF-IDF模型与KNN算法分类思想,得出不同行业的网络信息安全威胁程度,并划分出较低、适中以及较高三类等级。在此基础上,根据行业特点深入剖析了不同行业产生信息安全问题的原因,并提出了相应的改进措施和建议。     

基于单亲遗传算法的设施布置问题研究

用单亲遗传算法解决设施布置问题,结合设施布置问题的实际需求,提出了S型的编码顺序和基因修正算子,并在赌盘选择方式的基础上,提出了“多个体最优保持”的改进,使算法可求得多个最优解个体。最后通过算例分析和比较,分析了修正概率算子对算法的影响,验证了修正算子和对单亲遗传算法的改进效果,验证了改进单亲遗传算法的有效性。