混沌免疫优化组合算法

利用混沌迭代的遍历性和内在随机性。提出一种混沌免疫优化组合算法．该算法综合了免疫进化算法和混沌优化算法各自的空间搜索优势，将混沌变量加载于免疫算法的变量群体．利用混沌搜索的特点对记忆库群体进行微小扰动，并逐步调整扰动幅度．实验结果表明，该算法能明显改善免疫进化算法的收敛性能，搜索效率也得到了显著提高．     

混沌梯度组合优化算法

提出一种混沌梯度组合全局优化算法，并对该算法进行了收敛性分析．算法首先采用改进的变步长梯度法得到某个优化值，然后利用变尺度混沌搜索跳出局部极小，经过反复组合迭代，直至到达最优解．仿真结果表明，该算法能充分发挥梯度法寻优的快速性和混沌法寻优的全局搜索能力．     

一种动态分级的混合粒子群优化算法

针对粒子群算法早熟收敛和搜索精度不高的问题,提出一种动态分级的混合粒子群优化算法．该算法采取３种级别的并行粒子群算法,分别用于全局搜索和局部搜索及二者的结合,并根据搜索阶段动态调整各种级别中并行变量的数目．在全局搜索中,将混沌机制引入算法中以增强算法的全局搜索能力;在局部搜索中,采用单纯形法对适应度最优解进行局部寻优．仿真实验表明,该算法比其他优化算法具有更好的性能．     

一种新型Skew Tent映射的混沌混合优化算法

针对已有的混沌优化算法几乎都是利用Logistic映射作为混沌序列发生器,而该混沌序列的概率密度函数呈两头多、中间少的切比雪夫型的分布性质,不利于搜索的效率和能力,为此,首先构造一种新型混沌映射序列发生器—Skew Tent映射并结合迭代优化特点加以改进,然后分析了它的混沌特性．其次,将改进的混沌映射与Alopex启发算法相结合,充分发挥Alopex算法的快速搜索能力和混沌优化全局寻优的特性,提出一种混沌混合优化算法,提高了算法的收敛速度和有效搜索全局最优解．最后,仿真算例验证了该算法的有效性和Skew Tent混沌映射的应用前景．     

融合递减策略与Fuch混沌机制的改进YSGA算法

为增强绯鲵鲣算法搜索的覆盖性及寻优的精准性以优化全局探索能力和局部开采能力,提出一种融合步长因子递减策略与混沌局部增强机制的改进绯鲵鲣优化算法(IYSGA)。首先,该改进算法在标准YSGA算法基础上,设计了一种动态的步长因子递变模式以实现绯鲵鲣算法高效全面的搜索,此策略有利于提高算法的搜索效率并扩大寻优范围;其次,混沌搜索机制则是借鉴Fuch映射理论优越的混沌特性与较好的局部收敛性能而构造的一种当前最优解的局部再开采方式,以完成对YSGA算法的局部搜索性能的改善。该耦合方法对YSGA的改进,有利于实现IYSGA算法全局探索与局部搜索能力间的多轮动态迭代平衡。最后,通过数值实验验证了IYSGA算法优越的并行迭代寻优性能与稳健性。     

基于混沌搜索的模糊控制器参数最优设计

基于混沌变量，本文提出一种模糊控制器最优设计方案．离线优化采用混沌算法，将混沌因子引入到模糊控制器参数域的优化搜索中，用载波方式将优化变量转变成混沌变量，再利用混沌运动的遍历性和随机性直接寻优，得到模糊控制器参数的全局次优解．在线优化采用共轭梯度下降法，把混沌搜索后得到的全局次优值作为梯度下降搜索的初始值，实现混沌全局粗搜索和梯度下降局部细搜索相结合的优化目的，能很快找到模糊控制器参数的全局最优解．最后对算法的收敛性进行了证明．     

变尺度混沌光强吸收系数的萤火虫优化算法

针对基本萤火虫算法存在早熟现象,提出了一种变尺度混沌光强吸收系数调整策略的混沌萤火虫优化算法。首先,应用Sinusoidal映射产生混沌变量来描述光强吸收系数;其次,在算法迭代过程中引入变尺度混沌扰动,使光强吸收系数与迭代次数呈线性变化;最后,将萤火虫群分成三个子种群协作合作,可有利于增强算法搜索前期的全局探索能力和搜索后期的局部细化搜索能力。通过标准测试函数测试,实验结果表明算法是有效的,比基本萤火虫算法有了较好的寻优精度和收敛速度。     

蚁群混沌混合优化算法

为了克服混沌搜索的盲目性,提出了一种蚁群算法和混沌优化算法相结合的混合优化算法,该算法利用蚁群算法中信息素正反馈的思想指导当前混沌搜索的区域。工作蚁群按照信息素的浓度高低,分别按照不同的概率搜索不同的搜索区域,从而可减少混沌盲目搜索的次数。仿真结果表明,该方法能够明显提高混沌优化算法的寻优效率,同时算法的通用性将有所提高。另外,对于含有多个全局最优解的函数,在一次寻优过程中,该算法可以找到全部最优解,这是通常混沌搜索算法所不具备的。     

变尺度混沌蚁群优化算法

将变尺度混沌搜索算法融合到蚁群算法中,并用于求解连续空间优化问题。蚁群算法每一次迭代结束时,就使用混沌搜索算子在当前全局最优解附近搜索更好的解。而随着蚁群算法的进行,混沌算子搜索范围逐渐缩小,这样,混沌算子在蚁群搜索的初期起到防止陷入局部最优的作用,在蚁群搜索后期起到提高搜索精度的作用。将变尺度混沌蚁群优化算法用于求解函数优化问题的实验结果表明,该算法在求解包括欺骗性函数和高维函数在内的多种测试函数优化问题方面具有很好的效果。     

基于混沌序列的粒子群优化算法

提出一种改进粒子群局部搜索能力的优化算法,对于陷入局部极小点的情性粒子，引入混沌序列重新初始化，在迭代中产生局部最优解的邻域点，帮助情性粒子逃商束缚并快速搜寻到最优解．对经典函数的测试计算表明。改进的混合算法通过微粒自适应更新机制确保了全局搜索性能和局部搜索性能的动态平衡，而且保持了PSO计算简洁的特点，在收敛速度和精度上均优于普通的PSO算法.     

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.     

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.     

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.     

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.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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