基于指纹膜与航迹推算的井下人员定位系统

针对RSSI指纹膜定位方法受矿井环境影响较大,而基于航迹推算的定位方法易形成误差累积的问题,设计了基于指纹膜与航迹推算的井下人员定位系统。该系统周期性采集人员的位置信息与运动姿态信息,利用K近邻和峰值检测方法求解指纹定位结果和航迹推算结果,并对定位结果进行加权融合得到目标位置。测试结果表明,该系统明显提高了定位精度和稳定性,对煤矿巷道复杂环境具有较强的适应能力。     

基于改进ELM的煤矿井下定位算法

提出了一种基于改进极限学习机(ELM,extreme learning machine)神经网络的煤矿井下人员定位算法,针对测距模型易受井下复杂环境干扰,无法准确测距的问题,选用基于指纹的位置匹配模型;使用极限学习机将指纹和位置进行匹配,选用改进鲸鱼优化算法(IWOA,improved whale optimization algorithm)选取ELM合适的输入权值和隐含层阈值,以提高定位精度。在定位的在线阶段,将新的指纹数据代入带动态权值因子的在线顺序极限学习机(DOS-ELM,dynamic weight factor online sequential extreme learning machine)模型对定位模型进行动态调整,以克服电磁传播环境变动使定位结果产生的误差;仿真实验结果表明,该模型的定位误差在1.5 m以内的置信概率为72%,平均定位误差为1.64 m,与其他算法的实验结果相比,文章算法鲁棒性强,定位精度高。     

复杂环境下的井下人员定位算法及仿真研究

研究井下人员准确定位问题,矿井环境十分复杂,受到大量噪声干扰,传统方法难以实现精确定位.为提高煤矿并下人员定位精度,将接收信号强度(RSSI)和混沌粒子群相算法结合,提出了一种改进RSSI的井下人员定位方法.算法首先根据接收信号强度初步确定井下人员与锚节点距离,然后采用最小二乘法对井下人员位置进行估计,并利用混沌粒子群对位置进行优化,进一步提高了定位精确度.结果表明,相对其它定位算法,改进RSSI算法提高了井下人员定位精度,非常适用于复杂环境下的井下人员定位.     

煤矿井下节点合作加权质心定位算法

针对煤矿井下长距离巷道内人员定位信号存在衰减大、定位精度低的问题,提出了一种节点合作加权质心定位算法。该算法在ZigBee通信环境下,通过参数寻优思想在长距离巷道内人员定位时选择近距离虚拟参考节点(已定位的未知节点)与参考节点合作使用,利用改进的小区域三角形加权质心定位算法对未知节点进行初始定位,然后通过坐标修正确定未知节点的位置。仿真与实验结果表明,利用参考节点与虚拟参考节点合作定位,减少了远距离参考节点的使用,可以解决因距离远导致的信号衰减大的问题,提高了井下人员定位的精度;该算法的平均定位误差为1.5 m,可满足煤矿井下长距离巷道内人员定位精度的要求。     

基于WI-FI的井下定位算法研究

基于射频指纹的室内定位算法有很多,现提出基于射频指纹的应用在煤矿巷道这种特有的环境特征的一种新的定位算法。根据无线信号的衰减特性,将距离接入点3m处的接收信号强度值设为阈值,若设备接收的信号强度值大于阈值则直接定位到此接入点处。若信号强度低于阈值,则根据射频指纹数据库数据得到估计位置。在煤矿中移动目标的速度一般小于10m/s,根据这一特征,算法中设定前后两次的定位位置不能超过10 m;若超过10 m,则取前一秒的定位位置与该秒采用数据库匹配得出的位置的中点。将这些特征应用到射频指纹定位算法中可以非常有效的减少环境对信号强度的影响。通过实验表明,该定位算法具有较高的定位精度。     

基于蝙蝠算法的位置指纹定位技术的研究

为了改进室内位置指纹定位技术存在离线阶段工作量大、定位精度有限、鲁棒性较差的缺点,提出了一种基于蝙蝠算法的位置指纹定位技术的方法。该方法利用中点插值法和信道衰减模型自动生成指纹数据库从而代替了离线训练阶段,实现了定时自动更新数据库的功能,并且将[K]近邻算法和蝙蝠算法结合应用于匹配算法的阶段,最终实现定位功能。该方法与传统位置定位技术相比降低了整体定位的工作量,能快速应对环境变化对定位结果的影响,最后在给定的仿真环境下进行了定位性能的测试,结果显示该方法较其他算法相比平均定位精度大约提高了23.14%,绝大部分的盲节点的定位误差范围在1.5 m以内,显示出在定位精度、鲁棒性和适应环境变化方面的优势。     

一种改进的煤矿井下无线传感器网络定位算法

针对煤矿井下巷道狭长,传感器节点分布不均匀,环境恶劣,井下人员定位不明确。传统算法定位精度不高。为此,提出一种改进DV-Hop的煤矿井下节点定位方法,利用无线信号同种介质中传播速度不变性,并利用节点间数据包传送时间对未知节点的估计距离进行修正。实验结果表明,改进算法有效地提高了无线传感器网络节点的定位精度,减少了定位误差,更加适合于类似于煤矿井下场景的定位需求。     

基于WiFi信号强度特征的室内定位系统设计

针对室内GPS定位无法准确获取位置信息的问题,在Android平台上设计利用WiFi信号强度特征进行定位的系统。该系统由安卓客户端、Tomcat服务器以及MySQL数据库组成,在一般位置指纹定位算法的基础上,通过MAC地址对无线接入点( AP)进行过滤,选取固定的参考AP获取位置指纹信息,并结合改进的K最近邻匹配算法,进一步减小定位误差。实验结果表明,该系统定位速度快、定位精度高,具有较好的室内定位效果。     

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。     

一种高效的大监控区域移动目标追踪算法

针对目前无线传感器网络中利用位置指纹进行移动节点室内追踪时,为提高追踪精度引入的训练及匹配计算量大的问题,提出了一种兼顾定位精度和计算效率的算法。该算法适合锚节点稀疏分布的大监控区域,通过锚节点和参考位置点的局部匹配降低指纹匹配的复杂度,利用加权K-近邻算法获得粗定位,再通过融合目标节点加速度信息的卡尔曼滤波进一步减少追踪误差。仿真实验表明,本文算法具有良好的定位一致性和较高的定位精度,在指纹间隔10 m,接收信号强度指示值的测量方差高达16时,追踪过程中平均定位误差为1.4 m,适合室内移动目标的实时追踪。     

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     

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.     

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。