关于火电厂汽轮发电机组振动的分析和诊断

在火电厂的众多设备当中,汽轮机组的振动异常是非常常见的一种情况,为了更好的保证火电厂当中汽轮机的正常运行,我们需要对火电厂生产运行过程当中汽轮机异常振动进行分析,因为火电厂汽轮机运行过程当中发生振动的原因是非常多的,并且对于具体的原因比较难确定,所以说为电力检修部门来提供基础的分析依据是十分重要的,我们只有查明了原因才能够更好进行维修。     

汽轮机通流部分故障诊断方法分析

在火电厂中,汽轮机作为原动机发挥着重要的作用.其中,通流部分的安全运行对电厂的影响较大.通过阐述火电厂汽轮机的工作原理,阐述了汽轮机通流部分的具体工作原理,介绍了汽轮机通流部分的故障类型及其原因,并介绍了以神经网络为主的故障诊断方法,希望对提高汽轮机的生产效率提供一定的借鉴.     

耐高温转速传感器设计

航空发动机的转动频率对其工作效率、安全性和可靠性等都具有重要影响,过快和过慢的数值都会影响发动机的运行状态,我国发动机测试技术起步比较晚,因此对发动机参数的测量显得尤为重要,设计了一种基于电涡流原理的高温转速传感器,符合高温状态下对发动机转速的测量,可有效地监测发动机运行效率。     

分析智能控制在火电站锅炉燃烧系统中的应用

锅炉燃烧系统是火电厂重要的组成部分,直接关系到火电厂机组的运行效率和安全性。由于锅炉燃烧系统具有惯性、非线性、延迟性等特点,所以无法建立有效的数据模型,对燃烧系统燃烧效率做出有效的评估。将智能控制技术应用在火电厂锅炉燃烧系统中,可以提高燃烧系统的燃烧效率,降低二氧化碳、氮氧化物等污染气体的排放量。本文主要分析了遗传算法、人工智能、模糊控制等智能控制技术的应用。     

基于极化因子神经网络的火电厂制粉系统故障诊断技术

制粉系统是火电厂的主要设备,其安全稳定运行对发电企业的经济生产具有十分重要的意义;针对制粉系统的运行特性和故障分析,提出了基于极化因子神经网络的火电厂制粉系统故障诊断方法,该方法将故障征兆相应的过程变量作为输入,将制粉系统故障类型作为输出,通过训练神经网络建立其系统故障诊断模型,其中训练过程中采用极化因子来自动调整神经网络的收敛速度,从而在满足误差目标的前提下,防止其陷入局部极小;选取实际火电厂制粉系统3个典型故障及其相对应的9个故障征兆参数进行了实验;结果表明,该方法具有良好的收敛性,完全可以满足火电厂制粉系统现场故障诊断的要求.     

电气自动化技术在电力系统及火力发电中的应用研究

火电厂使用电气自动化技术展开生产,有助于加速工业转型和升级,对于推动电力企业的长远发展具有重要价值。基于此,首先分析了电气自动化技术具有的优势,其次对火电厂应用自动化技术现状展开了分析,最后提出了运用电气自动化技术的建议。通过对自动化技术的研究,逐渐完善电力系统,提高火力发电效率,实现节能减排、提高火电厂收益的目的。     

火电厂供电标煤耗的影响因素

供电标煤耗又称标准供电煤耗,是指火力发电厂提供的每1 k Wh电能的平均标准煤耗。供电标煤耗是根据火电厂最终产品的供电量计算的消耗指数,反映了火电厂的运行经济性,是火电厂运行状态的重要评价指标之一。文章对火电厂300 MW机组影响供电标煤耗的主要因素进行了一些探索,并从火电厂机组经济运行技术上提出了降低火电厂供电标煤耗的解决措施。     

火电厂锅炉燃烧优化关键技术研究

随着社会经济的飞速发展和不断进步,人们的物质生活水平不断的提高,这就使得对于电力的需求量也变得越来越大,火电厂作为我国电力发展建设中的重要组成部分,要时刻保障人们的学习、生活和工作的正常进行。但是由于我国对于电力资源需求量不断地增长,促进了电力企业对于发电设备的更新和维护,同时也需要对于火电厂的锅炉燃烧进行相应的性能优化,从而促进锅炉燃烧过程中的原料使用效率,并且通过调整锅炉的操作变量还可以使得锅炉在运行的过程中实现经济、环保、安全运行的目的,有利于提高火电厂锅炉燃烧效率,减少锅炉燃烧造成的污染影响,对于火电厂的发展具有积极作用和意义。     

火电厂SIS系统安全防护探讨

随着信息化的快速发展,大部分火电厂实施了SIS系统,SIS系统给火电厂生产管理提供了方便,但同时也带来了一些网络安全问题。如果SIS系统安全防护措施不到位,将影响DCS控制系统的安全稳定运行,甚至造成火电厂生产设备的损坏。文章从SIS在火电厂的实际应用出发,分析和讨论影响SIS系统安全所面临的风险,探讨SIS系统安全防护措施。     

火电厂锅炉运行中的节能对策研究

锅炉是火电厂能耗较高的部件,在火电厂节能减排战略实施背景下,锅炉节能改造势在必行。因此,以某火电厂为例,简单介绍了火电厂锅炉运行中的能源损耗情况,论述了火电厂锅炉运行中的节能对策,并进一步研究了火电厂锅炉运行中的节能策略应用效果,以期为同类火电厂锅炉节能改造提供参考。     

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.