一种新型井下人员组合定位系统设计

针对目前井下人员定位精度低、无法实时全局定位、搜救被困人员困难等问题,设计了一种基于微惯性测量组合(MIMU)导航技术和WiFi技术相结合的井下人员组合定位系统;给出了发生矿难后的基于该组合定位系统的搜救方案。该系统利用WiFi提供的可靠位置信息来给定MIMU最初的位置信息并校正MIMU的位置,弥补了MIMU误差随时间累积的缺点;利用MIMU的实时全局定位来弥补WiFi的局部定位。选用卡尔曼滤波将两者进行信息融合,进行最优组合处理。测试结果表明,该系统实现了对矿井井下人员实时三维全局定位及快速搜救,具有一定的工程实际意义。     

一种新型井下人员组合定位系统设计

针对目前井下人员定位精度低、无法实时全局定位、搜救被困人员困难等问题,设计了一种基于微惯性测量组合(MIMU)导航技术和WiFi技术相结合的井下人员组合定位系统;给出了发生矿难后的基于该组合定位系统的搜救方案。该系统利用WiFi提供的可靠位置信息来给定MIMU最初的位置信息并校正MIMU的位置,弥补了MIMU误差随时间累积的缺点;利用MIMU的实时全局定位来弥补WiFi的局部定位。选用卡尔曼滤波将两者进行信息融合,进行最优组合处理。测试结果表明,该系统实现了对矿井井下人员实时三维全局定位及快速搜救,具有一定的工程实际意义。     

基于MEMS技术的车载组合导航系统研究

针对当前车载GPS导航仪实时性和可靠性差的问题,设计出一种基于MEMS技术的低成本车载GPS/MIMU/GIS组合导航系统,建立了GPS/MIMU组合系统的误差模型,对该模型进行了计算机仿真研究,并运用地图匹配算法对GPS/MIMU/GIS导航信息误差进行修正;跑车试验表明,该组合导航系统成本低、精度高,可靠性强,特别适合于军用和民用车辆的导航定位。     

传感器网络节点定位算法在煤矿安全中的应用

研究煤矿井下安全问题,对井下人员进行定位跟踪,提高煤矿安全生产水平,应建立安全监测系统.针对煤矿井下巷道狭长,无线通信条件差,信号多径效应明显,在传统的监测中,无线传感器节点定位算法对井下环境敏感,导致节点定位误差较大.为了提高定位的精度,提出了一种基于RSSI的质心无线传感器定位算法.算法通过对无线电信号传播路径损耗模型的分析,利用锚定节点与待定位节点间的RSSI值确定质心的权值,从而提高算法对环境的适应性和定位精度.仿真结果表明,在相同的实验环境下,算法定位精度优于传统无线传感器节点定位算法,能够满足井下人员定位准确性,为煤矿安全生产监测系统设计提供了依据.     

煤矿井下定位仿真分析研究

关于煤矿井下定位优化建模问题,针对煤矿井下环境复杂,存在许多噪声干扰与随机误差,使得煤矿井下定位误差较大,无法实现人员的精确定位的问题,为减少噪声干扰,提高定位精度,提出了一种校正时间平均改进的方法最大程度消除煤矿井下噪声干扰与随机误差对定位精度的影响.通过Mathb软件进行试验仿真,仿真结果表明,该方法能够明显消除噪...     

煤矿井下精确定位系统研究

针对现有基于RFID,ZigBee,WiFi等技术的煤矿井下人员定位系统定位精度较低的问题,提出了融合可见光通信和惯性导航系统的煤矿井下精确定位系统。该系统以煤矿井下LED照明灯作为LED可见光定位基站,利用智能信息矿灯内置CMOS摄像头接收可见光信号进行定位,利用智能信息矿灯内置加速度传感器和陀螺仪数据进行时间积分得到井下人员运动轨迹和方向,并通过智能信息矿灯识别LED可见光定位基站的ID编码信息重新定位来修正惯性导航数据,从而实现精确定位。在煤矿井下布置8个LED可见光定位基站,通过5台智能信息矿灯以正常速度移动来测试系统定位精度,结果表明系统定位误差小于1m,满足煤矿井下人员定位精度要求。     

混沌粒子群优化神经网络的井下人员无线定位方法研究

针对井下人员定位系统定位精度较低,不能满足智慧煤矿的需求,提出一种基于混沌粒子群算法优化Elman神经网络的井下人员无线定位方法。该定位方法首先在井下巷道无线网络环境中,利用无线终端采集一定数量的样本点指纹数据库。其次初始化Elman神经网络,利用混沌粒子群优化算法对神经网络权值和自连接反馈增益因子寻优。再次用指纹数据库对优化过的Elman神经网络进行训练和测试,建立神经网络定位算法模型。最后通过无线终端采集定位点的指纹数据,由神经网络定位算法模型进行实时定位。经试验表明,该井下人员无线定位方法平均定位误差为1.35 m;而混沌粒子群算法优化Elman神经网络定位算法,其算法全局搜索能力更强,更适合井下时变环境中应用。     

基于TDOA和AOA的煤矿井下三维定位算法

针对煤矿井下现有定位算法的定位精度难以满足实际需求的问题,结合煤矿井下特殊的环境条件,提出了一种基于TDOA和AOA的煤矿井下三维定位算法。该算法利用巷道中的传感器基站测量未知节点发出的辐射到达不同基站的时间差和它们之间的相对角度,通过包含未知节点的坐标信息并结合基站本身的坐标信息进行定位。仿真结果表明,通过与定位模型的结合,基于TDOA和AOA的算法可有效消除测量值中的噪声干扰与随机误差,定位精度高。     

基于多小波的煤矿井下动力电缆故障定位研究

针对基于传统小波变换的煤矿井下动力电缆故障定位方法由于小波函数不具有对称性而存在定位精度差的问题,提出了一种基于GHM多小波的煤矿井下动力电缆故障定位方法。分析了多小波理论的原理,详细介绍了GHM多小波在煤矿井下动力电缆故障定位中的应用。仿真结果表明,动力电缆故障电流信号经GHM多小波变换后各尺度的奇异点不会发生偏移,提高了故障定位精度。     

煤矿井下无线传感器网络节点三维定位算法

现有煤矿无线传感器网络节点定位存在定位精度差、功耗高等问题,提出一种基于信标节点规则部署的煤矿井下无线传感器网络节点三维定位算法,根据井下巷道特征成对部署信标节点,在定位估算时先将信标节点投影到与未知节点同一高度的水平面,再利用三边测量法进行平面定位,然后结合未知节点与信标节点的高度差即可实现三维定位。理论分析和仿真结果表明,该算法具有计算量小、通信量小、定位精度较高以及稳定性较好等特点。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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