基于IEC 61850的同步相量数据传输方法研究

目前,智能变电站同步相量测量系统仍然采用IEEE 1344规约并使用专用通道与主站进行通信,而未采用在智能变电站中普遍采用的IEC 61850标准通信,这既增加了电网建设投资,也给系统运维带来不便。针对上述问题,本文提出基于IEC 61850的同步相量数据传输方法,即将同步相量测量系统的传输方法映射到IEC 61850标准体系,并将现有的通讯服务所包含的功能在IEC 61850标准体系下找到实现的手段。首先针对高速的数据传输和快速控制提出实现方法,然后对IEC 61850服务不能完全实现的功能服务以规定的方式对功能做扩展填补缺陷。最后从统一变电站信息平台的角度,对本方案的前景进行了分析。结果表明同步相量测量系统转换到IEC 61850体系是可行的,并将为信息的联合分析提供了基础。     

基于SM2-SM3的IEC 61850通信报文加密算法

本文针对IEC 61850协议报文存在的安全问题,利用仿真软件模拟了IEC 61850通信过程,对其网络环境进行了重放攻击,验证了该协议的安全缺陷,为了增强报文的安全性,利用WINPCAP开发工具捕获IEC 61850数据报文,提出了一种基于SM2-SM3国密体系算法,对其报文进行了数字签名并验证,实验结果表明报文安全...     

基于IEC62439-3协议的智能变电站过程层网络监视方法研究与实现

IEC61850-90-4标准中引入了基于并行冗余协议（PRP）和高可用性无缝冗余协议（HSR）的组网方案,该组网方案与国内普遍推广应用的双星型网络在网络监视等方面具有明显的差异。本文在HSR、PRP的过程层组网方案基础上进行网络监视方法研究,提出了基于监视帧、nodetable表、IED上送状态等几种网络监视管理方案并对几种监视管理方案进行了分析比较,给出基于HSR、PRP网络的可选监视管理方案。从IEC61850-90-4组网方案的工程实施角度出发,解决标准中未涉及到的实际问题,为国内智能变电站发展提供了有益的技术支撑。     

基于IEC61850的通信仿真软件

基于IEC 61850标准,设计智能变电站测控仿真软件,实现IEC 61850服务器通信模块的仿真.     

智能变电站GOOSE通信网实时性分析

GOOSE是IEC 61850中定义的一种通用变电站事件模型类,对于实现设备间的互操作具有重要的意义。随着符合IEC 61850的智能变电站技术的快速发展,GOOSE在智能变电站的应用也日益深入广泛。分析了GOOSE通信网的传输机制和在智能变电站中的工作方式,并采用OPNET仿真软件对GOOSE网的两种拓扑结构的实时性进行了仿真研究和对比分析。     

基于IEC61850的线路保护装置的设计

IEC 61850标准日后必将会成为变电站到控制中心的唯一通信协议,然而目前变电站自动化系统依旧使用各种基于传统规约(如CDT、IEC 103、IEC 104等)的设备,因而保证私有协议转换到IEC 61850标准就是个急需解决的难题.本文以基于IEC 103的线路保护装置为例来实现互操作性,首先介绍了IEC 61850标准的对象建模技术、抽象通信服务接口、特殊通信服务映射以及MMS通信协议.其次,重点研究和分析了基于IEC 61850标准的线路保护装置的信息建模方法和配置文档的研究以及IEC 103规约到IEC 61850标准的映射.最后,通过IEDScout测试软件对互操作性进行测试,结果符合要求,即使基于103的装置支持IEC 61850标准.     

变电站通信协议的一致性测试系统设计

IEC 60870系列标准在我国已广泛应用,为了满足对一致性测试的要求,IEC 60870-5-6和IEC 61850第10部分:一致性测试两个关于变电站通信协议一致性标准正式颁布。本系统就是基于一致性测试标准,设计并实现了用于一致性测试的系统工具,介绍了它的动态模型、软件结构和测试环境。该系统可以进行自动协议判断、自动译码和最大限度的自动完成一致性测试。     

智能变电站系统网络性能测试与分析

网络是智能变电站信息交互的枢纽,信息传输实时性是否能满足变电站的要求是智能变电站的关键。本文结合某智能变电站系统网络性能测试的实际情况,分析了数据传输时延产生的原因。针对该问题,提出了基于优先级标签的变电站过程层(SESPL)信息综合传输方法,并对该方法有效性进行了验证。     

城市柔性配电网实时仿真平台IEC61850建模

南方电网公司建立了某大学城市配电网柔性互联系统示范工程来模拟和研究微电网与大量分布式电源接入实际配电网的运行情况。本文首先介绍了示范工程的基本构成和所用仿真平台的基础原理。其次,为满足仿真平台中电网模型和相关设备的IEC61850标准化,进而实现与其他IEC61850装置的成功交互,本文设计了一种涵盖实时仿真器“四遥”信息建模、UDP协议转换和MMS服务器软件实现的解决方案,并提供了相应的仿真平台端口通信验证方法、IEDScout模型验证方法和“四遥”功能验证方法。最后,本文完成了实时仿真器的信息建模、UDP到IEC61850的协议转换,实现了实时仿真器与IEC61850客户端的数据传输和配电网系统中的“四遥”功能,为后续的工程实现提供指导,也为国内新型配电网运行模式和IEC61850的研究提供参考。     

基于区分服务和数据融合的WSN数据收集协议

对典型数据收集协议进行分析和比较,针对实际应用需求,设计一种基于区分服务和数据融合技术的数据收集协议DSDA。该协议通过构造高效的簇-树网络拓扑结构、对网络中数据流采用区分服务、在数据传输过程中采用网内数据融合技术,对现有协议进行改进。Matlab仿真测试证明,DSDA能有效节约能源,延长网络生命周期。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.