660MW燃煤机组DCS国产化改造方案研究

某电厂为4*660 MW空冷燃煤超临界火电机组,其3号机组主机DCS控制系统采用美国艾默生ovation3.5.0系统,辅助外围系统采用新华XDC800B系统。随着外部形势变化,近几年来国产DCS系统硬件质量的提升,国产DCS系统在超临界、超超临界火电机组上自主可控的趋势越来越明显,大型火电机组DCS控制系统改造也越来越具备规模性。以其3号机组DCS控制系统改造升级为国电智深的EDPFNT+系统,提出了详细具体的实施方案,同时完善了工控网络安全相关系统方案和要求等,以期为火电厂DCS控制系统改造提供借鉴参考。     

百万机组DEH系统首次伺服卡在线更换实践

本文针对国内大型燃煤火电机组、国产DCS与DEH一体化控制系统在额定工况下首次完成在线伺服卡更换的实践,揭开了特殊方式下DEH快速控制系统软硬件相互紧密耦合的特性,克服了伺服子卡隐性故障排查和在线操作的高风险挑战,总结出了一套安全有效的实施方案,为解决高精端自动控制系统的维护难题提供范例.     

DCS一体化控制在大型火电厂的应用

为了提高控制水平,大型火电机组全厂DCS一体化程度越来越高。本文以国产DCS—HOLLiASMACS系统在广东南海2X300MW燃煤扩建机组上的成功应用,阐述了一体化设计方案。     

贵溪电厂DCS数据通讯故障的分析与研究

对贵溪电厂一台300MW机组的DCS系统出现的故障进行分析和研究。确定了故障原因并采取了有效的措施,消除了故障,提高了DCS系统运行的可靠性。     

火力发电机组DCS控制系统自主可控改造展望

随着互联网、人工智能等技术在电力行业的广泛应用,DCS技术得到迅速的发展和完善。国产DCS系统在600 MW及以上机组的广泛应用,打破了国外DCS系统垄断的现状,表现出较强的国际影响力和竞争力。同时,由于电厂DCS控制规模增大,过程控制也有更加严格的要求,DCS系统作为中央控制系统发挥着越来越重要的作用,在机组安全性和经济性方面也起着举足轻重的影响。文章简述火力发电机组DCS控制系统自主可控改造的必要性及可行性,以托克托某电厂为例,总结自主可控DCS改造项目的经验,对日后火电机组自主可控工程开展实施具有一定参考价值。     

DCS系统维护常见问题分析

随着自动化水平的日益提高,给电厂节省大量劳动力的同时也使运行人员对DCS系统依赖程度也越来越高。因此DCS系统的稳定性及其可靠性显的尤为重要。本文通过对DCS系统常见的电源故障、网络故障、控制器故障及DCS软件故障等问题进行了分析并提出了防范措施,对今后DCS系统运行及维护提供了帮助,并有一定的指导意义。     

600MW机组仿真机的虚拟DCS系统开发

对火电机组分散控制系统（DCS）的仿真采用先进的虚拟DCS技术,这样可以在仿真机中实现对机组DCS系统中控制逻辑和控制策略的全仿真,除能对运行人员和热控人员进行培训外,还具有对真实DCS系统进行调试与优化的先进功能.以安徽平圩发电有限公司600MW机组的FOXBORO I/A Series DCS系统为虚拟对象,介绍600MW仿真机虚拟DCS的系统结构和开发过程,其中主要介绍了虚拟DCS的核心代码的实现.     

DCS故障排除与维护

介绍DCS系统维护的措施,并从DCS系统本身软硬件故障和外部环境对DCS系统的影响两方面讨论DCS常规故障的解决方法和日常维护要求.     

核电站安全级DCS系统故障及维护策略研究

对于核电站安全级DCS系统来说,除了要监视并控制保护系统工艺参数符合运行要求之外,还要避免安全级DCS系统自身故障导致的保护系统降级或者跳堆。本文首先对DCS系统故障进行了分析和定义,给出了故障识别及故障信息获取方式,并分析了DCS故障诊断方法,最后对故障后的维护策略进行了研究,结合相关标准和法规提出的要求,初步说明故障分析的合理性和维护策略的可行性。     

分散控制系统改造现状及展望

为提高火电机组的自动化、信息化水平,降低控制系统的故障率,对分散控制系统(DCS)进行改造。从项目意义、项目特点、开展方式、现有成果等方面,对我国几个火电机组DCS改造高峰期进行回顾和分析。针对技术管理,总结了"前期投入与人力资源"、"组态设计与厂家能力"、"调试深度与厂家经验"、"调试时间与调试质量"四对主要矛盾;针对项目管理,归纳了"改造实施主体与改造深度"、"改造投入与改造质量"两对重要矛盾。为解决这些矛盾,对DCS改造各参与单位的特点进行分析,提出了一种项目管理新机制。利用技术监督定位和科技研发水平的积极优势,有效提高了DCS改造的效率、质量。将技术监督、隐患排查、控制优化等工作的新成果、新思路与DCS改造有机结合,实现了火电机组在DCS改造后安全性、可靠性、经济型和灵活性的保障和提升。     

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.