模糊PID和Hopfield神经网络在矿井通风系统中的应用

针对传统的PID控制或者单一的模糊控制无法准确控制矿井通风系统风量的问题,提出了一种采用模糊PID调节器和Hopfield神经网络调节器对矿井通风机的转速、风门、风量进行控制的方法。该方法利用模糊控制器对PID参数进行实时修正,并结合Hopfield神经网络的联想记忆功能和反馈调节特性,实现矿井通风机风量的快速、稳定输出。仿真与实验结果表明,模糊PID调节器和Hopfield神经网络调节器可以准确控制矿井通风机的转速和风量,实现通风系统的稳定输出。     

矿井局部通风机远程数字监控系统设计

针对平煤股份一矿井下局部通风机监测系统无通信接口,地面控制站无法实时了解通风机运行状况的问题,设计了一套新型矿井局部通风机远程数字监控系统。该系统主要由地面监控站、通信控制器、通风机控制器等3个部分组成,各部分通过数据交换机接入现有的工业以太网形成独立的设备数字监控系统,实现了数据共享,从而共同完成井下局部通风机的远程监控。现场试验结果表明,该系统实现了对局部通风机和馈电开关运行状态的实时显示、控制及故障报警功能;实现了局部通风机本地控制和远程控制相结合的控制方式,达到了无人值守条件;实现了局部通风机与风速检测系统的联动,达到了节能减排效果。     

主要通风机远程监测系统的设计

针对现有的矿井主要通风机运行参数检测方式存在精度低、实时性差、无法实现全面监测的问题,提出了一种主要通风机远程监测系统的设计方案。该系统以C8051F020单片机为控制核心,通过数据采集模块采集主要通风机风压、风量、三相电压、三相电流、有功功率、效率、振动、电动机轴承温度等参数,对参数进行处理后实时显示在本地液晶屏上,并可通过GPRS网络将参数传输至上位机进行显示。试运行结果表明,该系统未出现错报及掉线现象。     

煤矿风机智能远程监控系统的应用研究

针对煤矿通风机高稳定性和强实时性的特殊控制要求,文章设计了一套煤矿风机智能远程监控系统,并提出了一种双机热备变频调速控制方案,主备控制器采用参数互备、故障自动切换等方式,保证了控制系统的实时性和不间断地稳定运行。该系统通过实时监测风机轴温、工作电压、巷道风压等参数,实现了风机工作状态的全面远程监控,并具有超限控制、报警、打印等功能。     

矿井通风除尘试验装置及PLC监控系统设计

基于实验室通风环境,设计了一套矿井通风除尘试验装置及PLC监控系统。该通风除尘试验装置集通风与除尘功能于一体,能自动监测通风机与除尘器的风量、风压、阻力等性能参数;PLC监控系统可对通风机、发尘器进行远程/就地开停及变频调速控制,实时监测通风机、发尘器运行状态、运行电流、运行频率等参数,模拟并实现了矿井通风系统的井下通风计算机远程集中监控。实际应用表明,该系统运行稳定可靠、操作简便、可扩展性强。     

矿井通风系统分级控制研究

针对现有矿井通风系统控制未从通风系统整体角度考虑的问题,基于矿井通风系统结构及风量分布特征,提出了一种矿井通风系统分级控制方法。首先,通过比较通风状况参数的实时采集值和安全设定值,得出各用风地点通风状况参数偏差量;然后,利用自动纠偏控制器对偏差量进行在线整定和修改,并通过PID控制器获得通风状态调整参数;最后,智能控制模块根据通风状态调整参数,分别控制主要通风机供电模块的变频器、电动风门、压风管路末端的充气式气囊,实现全矿风量控制、采区风量控制、工作面风量控制3个层次的风量动态调节。该控制方法满足通风系统内风量循序、系统、连贯地调控要求。     

基于物联网的矿井通风机远程监测系统设计

针对现有通风机状态监测系统只能在现场工控机或服务器上查看、分析数据的问题,设计了一种基于物联网的矿井通风机远程监测系统。该系统以S3C2440为处理器、Qt为编程语言、OneNET物联网平台为数据传输平台,可实时获取、分析矿井通风机的振动信号,实时感知矿井通风机的运行状态,从而实现矿井通风机设备的预知维修。     

煤矿提升机智能监控及故障诊断技术的研究

针对煤矿提升机传统监控系统存在控制效率低、监控不全面、故障诊断耗时较长以及远程运维困难等问题,本文通过分析煤矿提升机结构以及常见故障,提出了一种煤矿提升机智能监控系统及故障诊断技术方案。采用先进的传感检测技术、工业互联网技术以及上位机监控系统实现对煤矿提升机运行状态的实时监控与故障智能诊断,完成硬件系统选型和软件编程。结果表明,本文提出的煤矿提升机智能监控与故障诊断技术实现了对矿井提升机运行参数的实时监控,响应时间为2.89 s,并且能及时发现设备运行异常参数并进行报警,取得了较为满意的应用结果。     

矿井主要通风机监控系统设计

介绍了一种矿井主要通风机监控系统设计方案,详细论述了系统结构、功能及其软硬件设计。该系统硬件以S7-300PLC为核心,软件采用组态软件INTouch9.5实现,采用手动控制、系统就地控制、远程控制三级控制模式,实现了对主要通风机运行过程的实时监控功能。     

矿井局部通风机智能控制系统的设计

针对传统的矿井局部通风机变频控制系统仅随瓦斯浓度调节风量而存在的不足,文章提出了一种兼顾瓦斯浓度和煤尘浓度的矿井局部通风机智能控制系统的设计方案,介绍了基于模糊PID控制的瓦斯、煤尘浓度的模糊控制器的设计。通过对瓦斯浓度模糊控制器以及煤尘浓度模糊控制器的仿真可以看出,随着工作面瓦斯和煤尘浓度的不同,该智能控制系统会根据爆炸性气体的浓度变化,自动、连续、实时地对局部通风机进行调速。     

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。     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

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.     

Editorial: Special issue on recent advances in hybrid control theory and applications

正The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory.In recent years control problems have been arising with increasing frequency in widely different areas,which cannot be addressed using conventional control techniques.The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where     

Information for Authors

正Aim The Journals of Zhejiang University-SCIENCE(A/B/C)areedited by the international board of distinguished Chinese andforeign scientists,and are aimed to present the latest devel-opments and achievements in scientific research in China andoverseas to the world’s scientific circles,especially to stimulateand promote academic exchange between Chinese and for-eign scientists everywhere.     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。