多目标演化算法的进展研究

回顾多目标演化算法的研究历史,给出问题相应的数学描述;其次,分析经典的第一代多目标进化算法,阐明这一代算法的优点与不足;对新一代多目标进化算法作详细的分析,其主要特点是构造外部种群实现精英保留机制;最后多目标进化算法的研究方向作展望.     

带局部搜索的NSGA Ⅱ算法在负荷分配中的应用

为了改善NSGAⅡ算法的收敛性能,将局部搜索的思想融入到NSGAⅡ中,提出一种带局部搜索的NSGAⅡ算法(NSGAⅡ-LS).该算法采用基于惩罚的边界插入法(PBI)产生局部搜索的优化函数,并使用序列二次规划方法(SQP)进行求解.通过在3个多目标标准测试函数上的仿真实验,结果表明相对于NSGAⅡ,NSGAⅡ-LS具有更好的收敛性能.最后将NSGAⅡ-LS应用到带钢热连轧负荷分配优化计算中,给出了兼顾轧制力平衡、最低轧制功率和优良板形的目标函数表达式,对多目标进化算法在热轧负荷分配优化计算中的应用进行研究,指出了目标之间的冲突关系.     

解决多目标优化问题的差分进化算法研究进展

差分进化(differential evolution,DE)是一种简单但功能强大的进化优化算法.由于其优秀的性能,其诞生之日起就吸引了各国研究人员的关注.作为一种基于群体的全局性启发式搜索算法,差分进化算法在科学和工程中有许多成功的应用.本文对解决多目标优化问题的差分进化算法研究进行了综述,对差分进化的基本概念进行了详细的描述,给出了几种解决多目标优化问题的差分进化算法变体,并且给出了差分进化算法解决多目标优化问题的理论分析,最后,给出了差分进化算法解决多目标优化问题的工程应用,并指出了未来具有挑战性的研究领域.     

基于支配强度的NSGA2改进算法

NSGA2是一种简单、高效且被广泛使用的多目标进化算法(Multi-objective Evolutionary Algorithm,MoEA),但在求解实际工程领域中的高维、复杂非线性多目标优化问题(Multi-objective Optimization Problems,MOP)时,存在无法有效识别伪非支配解、计算效率低、解集收敛性和分布性较差等设计缺陷。对此,文中提出一种基于支配强度的NSGA2改进算法(INSGA2-DS)。新算法采用快速支配强度排序法构造非支配集,引入了考虑方差的拥挤距离公式,并通过自适应精英保留策略动态调整精英保留规模。基于标准测试函数的仿真实验表明,INSGA2-DS算法较好地改善了NSGA2算法的收敛性和分布性。     

多目标差分进化在热连轧负荷分配中的应用

提出一种基于差分进化算法的多目标进化算法, 该算法个体的选择是通过非支配排序和拥挤度距离进行综合考虑. 保证了算法收敛到Pareto最优解集的同时, 提高了最优解个体分布的多样性. 通过与非支配排序遗传算法Ⅱ(NSGA Ⅱ)算法进行仿真对比, 结果显示基于拥挤度排序的多目标差分进化算法在收敛性和Pareto最优解集分布的多样性上均优于NSGA Ⅱ算法. 最后将其引入到热连轧负荷分配优化计算中, 给出了目标函数的表达方式, 对多目标进化算法在热连轧负荷分配计算中的应用进行了研究.     

多目标演化算法的收敛性研究

基于群体搜索的演化算法求解多目标优化问题有独特的优势，多目标演化算法已有的研究大多为算法的设计和数值试验效果的比较，理论研究往往被忽视．该文讨论了多目标演化算法的收敛性问题，针对一种网格化的简单易于实现的多目标演化算法模型定义了多目标演化算法强收敛和弱收敛等概念，给出了判断算法收敛性的一般性条件；在变异算子为高斯变异、目标函数连续的条件下，证明了提出的算法强收敛．数值实验验证了算法的可行性和有效性．     

基于进化算法的多目标优化方法

进化算法在解决多目标优化问题中有其特有的优势.首先对多目标优化问题进行了描述;然后结合研究现状讨论了目前几种主要的基于进化算法的多目标优化方法,以及它们的优缺点;最后给出了多目标进化优化算法的一些应用,以及进化多目标优化算法的未来发展方向.     

基于多目标进化算法的MOEA/D权重向量产生方法

在进化多目标优化研究领域,多目标优化是指对含有2个及以上目标的多目标问题的同时优化,其在近些年来受到越来越多的关注。随着MOEA/D的提出,基于聚合的多目标进化算法得到越来越多的研究,对MOEA/D算法的改进已有较多成果,但是很少有成果研究MOEA/D中权重的产生方法。提出一种使用多目标进化算法产生任意多个均匀分布的权重向量的方法,将其应用到MOEA/D,MSOPS和NSGA-III中,对这3个经典的基于聚合的多目标进化算法进行系统的比较研究。通过该类算法在DTLZ测试集、多目标旅行商问题MOTSP上的优化结果来分别研究该类算法在连续性问题、组合优化问题上的优化能力,以及使用矩形测试问题使得多目标进化算法的优化结果在决策空间可视化。实验结果表明,没有一个算法能适用于所有特性的问题。然而,MOEA/D采用不同聚合函数的两个算法MOEA/D_Tchebycheff和MOEA/D_PBI在多数情况下的性能比MSOPS和NSGA-III更好。     

基于文化的多目标协同进化算法*

为了改进NSGAⅡ算法中存在的分布性等不理想问题,在NSGAⅡ的基础上提出了基于文化的多目标协同进化算法。该算法提出评测信念空间多样性的指标,从信念空间中提取知识,利用知识来指导种群的进化;提出知识假说集,以现有知识为基础产生新知识,加强局部搜索,加速算法收敛。仿真实验表明该算法较NSGAⅡ在收敛性及分布性方面均有明显提高。     

基于改进 NPGA 算法的多目标优化云任务调度算法

随着云计算的不断发展,传统的单目标优化下的任务调度已经不能满足用户的服务质量要求。论文选取运行时间、费用和负载均衡建立多目标优化的云任务调度模型,提出一种改进的多目标小生境 Pareto 遗传算法（NPGA）,采用相似任务序列交叉操作加快进化,再采用位移变异避免算法过早收敛。此外,通过自适应选取比较集合规模和小生境半径提高算法的收敛速度。仿真结果表明,改进后的 NPGA 算法在云调度中保持 Pareto 最优解的多样性和分布性更优。     

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.     

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)

正~~     

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