基于蚁群算法的车间作业调度问题研究

对基于蚁群算法的车间作业调度问题求解进行了研究,在分析了传统蚁群算法求解车间作业调度问题容易出现早熟、收敛于局部最优解以及搜索速度慢的缺陷,提出了一种改进的混合蚁群算法。该方法在信息素更新规则上利用信息素局部更新策略和全局更新策略来进行信息素的更新,并将领域搜索与蚁群算法相结合,从而求得问题的可行解。最后,基于benchmarks问题进行了实验仿真,实验结果证明该改进混合算法的有效性及可行性。     

基于改进蚁群算法的物流配送路径求解

蚁群算法是受自然界中蚁群觅食行为启发而提出的一种智能优化算法,通过介绍蚁群搜索食物过程中基于信息素的最短路径的搜索策略.以及蚁群算法在VRP问题中的应用,给出了用于求解物流配送路径问题的蚁群算法.并针对蚁群算法在求解过程容易陷入局部最优的情况,提出了算法改进的措施.     

基于多样信息素的蚁群算法

根据蚁群算法信息素更新的特性,提出了求解旅行商问题的多样信息素的蚁群算法。把蚁群的三种不同的信息素更新方式混合在一起,既利用了局部信息,又考虑了整体信息,将局部搜索和全局搜索相结合,使收敛性得到提高。针对旅行商问题的仿真实验结果,表明了该混合算法的有效性。     

改进蚁群算法求解最短路径问题

针对蚁群算法在求解最短路径问题时存在容易陷入局部最优解的问题,对经典蚁群算法提出三方面改进。首先,在初始化信息素浓度时加入方向引导,加快初始搜索速度;其次,在局部信息素浓度更新过程中采用信息素重分配思想,避免由路径信息素衰减过程导致的最优路径信息素浓度过分减少;最后,在全局信息素更新过程中引入动态因子,使其自适应地更新较优路径信息素浓度,以提高全局搜索能力。仿真实验结果表明,该改进算法可以保证收敛速度,并提高算法搜索到最优路径的几率。     

蚁群算法的改进及在TSP问题上的仿真验证

蚁群算法是一种新型的模拟进化算法，具有正反馈、分布式计算等特点。在介绍蚁群算法基本原理的基础上，针对基本蚁群算法求解速度缓慢、容易陷入局部最优等特点，采用分区搜索的思想，提出了一种改进的蚁群算法。它将搜索区域分成几个较小的区域进行局部搜索，得到了局部较优解，以此产生蚁群算法在全局搜索时的初始信息素分布，并结合局部与全局信息素调整等策略，大大地加速了算法的收敛速度。在TSP旅行商问题上的仿真验证表明它是可行性和有效性的。     

求解子旅行商问题的改进蚁群算法

已有求解子旅行商问题的蚁群算法存在容易早熟、易于陷入局部最优的问题。为此,提出一种改进的蚁群算法。将拥挤因子嵌入到蚁群算法的状态转移和信息素更新过程中,增强全局搜索能力,设计邻域搜索技术和局部变异技术,以提高解的质量和加快收敛速度。实验结果表明,该算法的求解质量和稳定性较好。     

改进的智能蚁群算法在TSP问题中的应用

研究旅行商领域优化路径问题,解决目前蚁群算法易陷入局部最优、搜索时间长等问题.为加快算法的速度优化结果,提出了一种改进的求解TSP问题的智能蚁群优化算法.算法前期采用了一种最近节点选择策略对路径进行优化,提高了搜索效率,使之适应大规模问题求解;后期改进了基本蚁群算法中信息素、挥发因子的更新规则,通过改进使得每轮搜索后信息素的增量能更好地反映求解的质量,有效地避免陷入局部最优,加快了收敛.通过改进后的蚁群算法,对TSPLIB中部分问题的仿真结果表明,在避免陷入局部最优和缩短搜索时间方面都取得了很好的效果.证明采取的优化蚁群算法,是可行有效的.     

求解TSP问题的一种改进蚁群优化算法

针对基本蚁群算法求解TSP问题时容易出现早熟和停滞现象的缺陷,提出了一种改进的蚁群算法。算法的基本思想是,将信息素分为局部和全局二种不同的信息素,在搜索过程中。对局部和全局信息素采用不同的更新策略和动态的路径选择概率,使得在搜索的中后期能更有效地发现全局最优解。以TSPLIB的数据进行实验的结果表明．在中大型问题上有着更好的发现最优解的能力。     

求解TSP问题的一种改进蚁群算法

TSP问题是典型的NP—hard组合优化问题,用蚁群算法求解此问题存在搜索时间长,容易陷入局部最优解的不足。本文提出了一种改进的蚁群算法。该算法在蚁群算法中植入遗传算法,利用遗传算法生成信息素的分布,克服了蚁群算法中搜索时间长的缺陷。此外,在蚁群算法寻优中,采用交叉和变异的策略,改善了TSP解的质量。仿真结果显示,改进的蚁群算法是有效的。     

基于拥挤度的参数自适应蚁群系统

在蚁群算法中,如何有效处理加速收敛和出现早熟、停滞现象的矛盾一直是一个困难的问题。通过引入拥挤度来加强搜索过程中蚂蚁之间的协调和配合,提出了一种基于拥挤度的参数自适应蚁群算法。该算法采用提前主动预防早熟的策略,将拥挤度嵌入到蚁群算法的状态转移和信息素更新过程中,让局部信息素更新参数随局部搜索状态自适应地调整,全局信息素更新参数随全局搜索状态自适应地调整,大大提高了算法全局搜索能力和自适应能力,同时采用了一种简单有效的变异算法来加快收敛速度。用多个TSPLIB范例进行比较实验,结果表明,改进算法无论是求解质量、稳定性以及收敛速度都有显著提高。     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

法律信息库系统

本文分析了法律数据库的结构和特点，介绍了采用面向对象设计方法和超文本数据库技术开发和实现法律信息库系统将作为重要网络资源之一为不同用户进行法律咨询服务。     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

International Journal of Automation and Computing Table of Contents

正~~     

Information for authors

正SCIENCE CHINA Information Sciences(Sci China Inf Sci),cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press,is committed to publishing highquality,original results of both basic and applied research in all areas of information sciences,including computer science and technology;systems science,control science and engineering(published in Issues with odd numbers);information and communication engineering;electronic science and technology(published in Issues with even numbers).Sci China Inf Sci is published monthly in both print and electronic forms.It is indexed by Academic OneFile,Astrophysics Data System(ADS),CSA,Cabells,Current Contents/Engineering,Computing and Technology,DBLP,Digital Mathematics Registry,Earthquake Engineering Abstracts,Engineering Index,Engineered Materials Abstracts,Gale,Google,INSPEC,Journal Citation Reports/Science Edition,Mathematical Reviews,OCLC,ProQuest,SCOPUS,Science Citation Index Expanded,Summon by Serial Solutions,VINITI,Zentralblatt MATH.     

Erratum to: Fast global kernel fuzzy c-means clustering algorithm for consonant/vowel segmentation of speech signal

正Erratum to:J Zhejiang Univ-Sci C(ComputElectron)2014 15(7):551-563doi:10.1631/jzus.C1300320The original version of this article unfortunately contained mistakes.Algorithm 6 should be as follows:Algorithm 6 FGKFCM-F clustering Input:(1)X={x_1,x_2,…,x_N},,x_iR~d,i=1,2,…,N,the dataset;(2)C,1C≤N,the number of clusters;(3)ε0,the stopping criterion;     

Journal of Zhejiang University-SCIENCE C (Computers & Electronics) Total contents

正~~     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.