改进型的扩大内桥备自投装置的应用

首先进行了110kV扩大内桥备自投的动作需求分析；其次给出了110kV扩大内桥接线备自投的逻辑实现配置；最后，在考虑了现场应用过程中主变保护闭锁备自投逻辑的利弊关系后，提出了一种较好的解决方案。在贵阳某110kV变电站的整组试验和运行情况表明，该装置能完全适应扩大内桥接线不同运行方式下不同的逻辑需求，具有较高的工程实用...     

基于单片机的安稳闭锁备投装置研制及应用

目前备自投在电网中有大量应用,但是对于110 kV变电站内进线备投与220 kV主站安稳间配合存在着矛盾,即在一定的运行方式下,要求当安稳动作时及时有效地闭锁备投动作,从而保障区域电力系统的稳定运行,在分析现有技术及电网保护装备的基础上,以STC单片机为控制器,自主开发研制一套装置旨在解决安稳远方实时闭锁备自投的问题,目前该装置在现场已通过各项功能测试,系统从主站动作到闭锁备投动作时间小于20 ms,且多次测试数据稳定,并在常德电网的试运行中运行正常.     

110kV变电站1.5台变压器失压解决方案

传统的进线备自投方式、母联备自投方式不能满足当前变电站运行的需求。本文以某110kV站采用单母刀闸分段带旁路主接线且已安装新规范具备加速跳闸功能的110kV备自投变电站为例,对比分析三种不同的优化方案,得出解决该地区110kV变电站1.5台变压器失压的针对性措施。期望此次研究能够给同行业者带来一定个参考。     

智能化改造变电站组网传动技术研究

以某110kV变电站智能化改造为索引,主变低压侧开关接入智能化10 kV备自投装置为模型,分析网采网跳组网方式下10 kV备自投装置传动主变变低开关的风险,提出增加级联交换机划分VLAN的解决措施,并通过搭建实验平台对方案进行结果论证。     

备自投装置异常动作问题探讨

供电网络为了保证供电可靠性,在变电站内通常会配置备用电源自动投入装置,简称备自投装置。当系统电源因为故障失电后,能快速自动将备用电源投入使用,保证供电的连续可靠性。备自投装置主要用于110kV及以下的中、低压配电系统中,在纯负荷变电站的220kV供电网络中也有配置。当变电站低压侧带有电源时,备自投的逻辑将受到影响,无法按照定值设定的时间动作,对供电稳定性和可靠性带来了一定的影响。本文结合某220kV负荷变电站备自投的实际动作情况,对这一问题进行了分析,并尝试提出一些解决方案。     

110kV网络备自投误动分析及改进措施

针对一起保护装置在运行中,因电源插件故障造成空开越级跳闸,使110kV网络备自投误动事件,找出空开越级跳闸和网络备自投误动的原因,并采取相应的处理措施.     

浅谈10kV分段开关备自投的相关探讨

本文将重点介绍10kV分段开关备自投方式,主要分析有无负荷均分功能的区别,并给出10kV备自投动作过程。同时,对备自投在现场工作的几个关键问题进行分析,并给出有意义的改进措施。     

基于电力系统备自投实现功能原理概述

备自投实现原理与电力系统中的"重合闸"装置类似,在实践中为了禁止止备自投装置短时间内多次重合、分开同一故障元件,备自投装置在内部控制程序里面设置了"充电"和"放电"互锁逻辑,这一点将会被考虑在内。备自投装置只能在充电完成以后才允许自投,而放电逻辑则是为了闭锁备自投装置,防止其误动作,为了防止电力系统的连续性,一定要发挥电力系统备自投应用性。     

微机备自投装置在企业电网中的运用

针对某企业高压电网中各种类型备用电源自投装置在设计、应用中的若干问题进行总结,提出备自投方案设计和应用中备用电源自投的启动条件、线路和母线电压的取用、备自投闭锁逻辑的设计以及一些特殊情况的处理原则,以满足企业电网的稳定供电。     

中天钢铁码头变电所10 kV备自投运行方式优化

10 kV供电系统广泛应用于码头和高速公路的变电所,随着国家对10 kV供电系统不间断供电要求的提高,变电所的建设更趋向于高效化和智能化。为了改变目前很多变电所的备自投装置比较落后的局面,考虑在一、二次系统中合理配置稳定可靠的备自投装置,以提高供电的稳定性,缩短故障停电时间。本文结合中天钢铁码头变电所实际运行操作需求以及变电所备自投方式的现状,进行了充分优化改进。通过多次试验和投产实际运行后的情况,充分证明备自投逻辑经过优化改进后满足变电所供电要求。     

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.