曲线曲在的形态算法及应用

从积分几何中的概念出发,证明了凸体形态和运算的一个重要性质,Ｆ（Ｓ,ｕ）＝Ｆ（Ａ,ｕ）＋Ｆ（Ｂ,ｕ）,从而将两物体的形态和归结为法矢相同的点集的形态和,并提出法矢球的概念,将物体表面各点的法矢顺序对应至球,即得到该物体的唯一法矢球表示,通过地法矢球的合并,同得得到两物体的形态运算结果,在理论上统一了二维、三维变体的形态运算,并给出二维、三维曲一、曲面的具体形态算法,此上不咄曲线、曲面形态算法的具体     

曲线曲面的形态算法及应用

从积分几何中的概念出发,证明了凸体形态和运算的一个重要性质： Ｆ（ Ｓ,ｕ）＝ Ｆ（ Ａ,ｕ） Ｆ（ Ｂ,ｕ）,从而将两物体的形态和归结为法矢相同的点集的形态和,并提出法矢球的概念,将物体表面各点的法矢顺序对应至球,即得到该物体的唯一法矢球表示,通过对法矢球的合并,则得到两物体的形态运算结果,在理论上统一了二维、三维实体的形态运算,并给出二维、三维曲线、曲面的具体形态算法．此外还给出曲线、曲面形态算法的具体应用,如扫成曲面造型、字型合成、非刚体运动的广义内插等．     

凸多面体的快速形态和算法

在研究传统形态算法的基础上,将凸多面体的形态和算法简化为面与面的形态和,结合三维物体的法矢球模型,引入参考平面的概念.参考平面将三维空间的凸多边形分解成两部分,分别计算对应的两部分的形态和,并去掉重复边和面.提出一种凸多面体的快速形态算法,与传统方法相比,该方法简单、直观,算法效率可提高6～10倍.实验证明,该方法是可行的、有效的.     

三维形体的形态运算及应用

本文首先讨论了边界表示的物体的形态学运算问题，文中讨论了任意形状的物体，包括凸物体和非凸物体，引入了负形体的概念，并提出了2D和3D连续物体的Minkowski运算的统一算法。利用这一算法，提出了3D任意形体间的变形新算法，把边界表示的物体的形态学运算的概念扩展到任意曲线和任意曲面上，并且介绍了3D物空间中曲线的概念和3D硪空间双参数曲面的概念。文中任意形体的3D变形算法能很好地解决具有不同拓扑结构的3D边界表示的物体之间的变形问题。     

三维形体的形态学运算及应用

本文首先讨论了边界表示的物体的形态学运算问题。文中讨论了任意形状的物体，包括凸物体和非凸物体；引入了负形体的概念；并提出了２Ｄ和３Ｄ连续物体的Ｍｉｎｋｏｗｓｋｉ运算的统一算法。利用这一算法，提出了３Ｄ任意形体间的变形新算法，把边界表示的物体的形态学运算的概念扩展到任意曲线和任意曲面上，并且介绍了３Ｄ物空间中曲线的概念和３Ｄ物空间双参数曲面的概念。文中任意形体的３Ｄ变形算法能很好地解决具有不同拓扑结构的３Ｄ边界表示的物体之间的变形问题。     

面向Web服务工作流系统的访问控制模型

提出了一种面向Web服务工作流系统的访问控制模型（WSWF-RBAC）。在基于角色的访问控制模型基础上引入系统资源的概念,把Web服务对象、属性和其它功能模块当做资源统一管理。引XT资源访问模式的概念,在约束条件下通过与资源的运算生成系统权限,从而实现了对权限的精细管理和动态调整能力。通过扩展web服务访问的角色集和用户集,并引入角色扮演对象,实现了工作流系统中Web服务与其它模块访问控制的一致性。将该模型应用于库房供应链系统中,运行结果表明,该模型能够增强Web服务工作流系统授权的灵活性和安全性。     

物体变形的广义形态变换方法

将广义形态变换理论用于非刚体运动的描述和内插，通过对非刚体的凸剖分把非刚体的运动分解为非刚体的变形与子凸集的旋转，提出物体近似骨架的概念；通过近似骨架实现子凸集匹配，实现了任意非同拓扑结构(包括有孔及凹多面体)物体的变形．广义形态变换具有基于体元的变形方法和基于边界形状的变形方法的优点，同时克服了它们的缺点．实验表明，该方法变形物体边界光滑、定位精度高、计算速度快，可应用于CAD、虚拟现实和生物医学工程。     

基于Vague集的次协调数据库的研究

次协调数据库的数据模型是用来处理数据库中不完全信息和矛盾信息。基于这种数据模型,将Vague集的概念引入,并基于新模型重新定义选择、投影、连接及decision等运算,再使用基于Vague集的次协调数据库的查询语言（PQL）查询矛盾信息并作出决策以解决矛盾,从而扩展了传统次协调数据库模型的应用。     

平面点集凸壳的快速算法

提出一种计算平面点集凸壳的快速算法。利用极值点划分出四个矩形,它们包含了所有凸壳顶点,通过对矩形中的点进行扫描,排除明显不是凸壳顶点的点,剩余的点构成一个简单多边形。再利用极点顺序法判断多边形顶点的凹凸性并删除所出现的凹顶点,最终得到一个凸多边形即为点集的凸壳。整个算法简洁明了,避免了乘法运算（除最坏情况外）,从而节省计算时间。     

IFS吸引子空间边界的快速精确测定

迭代函数系数（ＩＦＳ）是分形理论与应用的重要分支,求取它的分形吸引子边界一直没有有效的方法。本文提出了一种“内分裂变换”方法。它作用在最外层套子上（ＩＦＳ的套子是个球集,它包含ＩＦＳ分形吸引子,尤其是每个套子包含吸引子在对应仿射变换下的图像,并且,使套子继续进行内部分裂并产生新的球集,以进一步接近ＩＦＳ的吸引子。然后,本文给出有关内边界和外边界的概念,内边界将除掉无用计算元素,只有剩余套子球继续进     

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)

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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