Cooperative Sensor Anomaly Detection Using Global Information

Sensor networks are deployed in many application areas nowadays ranging from environment monitoring, industrial monitoring, and agriculture monitoring to military battlefield sensing. The accuracy of sensor readings is without a doubt one of the most important measures to evaluate the quality of a sensor and its network. Therefore, this work is motivated to propose approaches that can detect and repair erroneous (i.e., dirty) data caused by inevitable system problems involving various hardware and software components of sensor networks. As information about a single event of interest in a sensor network is usually reflected in multiple measurement points, the inconsistency among multiple sensor measurements serves as an indicator for data quality problem. The focus of this paper is thus to study methods that can effectively detect and identify erroneous data among inconsistent observations based on the inherent structure of various sensor measurement series from a group of sensors. Particularly, we present three models to characterize the inherent data structures among sensor measurement traces and then apply these models individually to guide the error detection of a sensor network. First, we propose a multivariate Gaussian model which explores the correlated data changes of a group of sensors. Second, we present a Principal Component Analysis (PCA) model which captures the sparse geometric relationship among sensors in a network. The PCA model is motivated by the fact that not all sensor networks have clustered sensor deployment and clear data correlation structure. Further, if the sensor data show non-linear characteristic, a traditional PCA model can not capture the data attributes properly. Therefore, we propose a third model which utilizes kernel functions to map the original data into a high dimensional feature space and then apply PCA model on the mapped linearized data. All these three models serve the purpose of capturing the underlying phenomenon of a sensor network from its global view, and then guide the error detection to discover any anomaly observations. We conducted simulations for each of the proposed models, and evaluated the performance by deriving the Receiver Operating Characteristic (ROC) curves.     

具有非倍测度的参数型Marcinkiewicz积分交换子估计

本文证明了由参数型Marcinkiewicz积分Mρ和Lipshitz函数b生成的交换子Mρb的有界性.在M的核函数满足较强的Hrmander条件下,证明了Mρb不仅从Morrey空间Mpq(μ)到RBMO(μ)有界,从Lebesgue空间Ln/β(μ)到空间RBMO(μ)有界,而且从Morrey空间Mpq(μ)到Lipschitz空间Lip(β-np)(μ)有界,这里p=n/β.     

应用物像分析人像的特征识点与物理空间探究

监控视频图像处理的一个关键问题是如何分析嫌疑人像。人与物在物理（地理）空间的相伴决定了人像和物像在视频空间中的伴随性生成关系。为分析嫌疑人像可选择、设定和建构嫌疑物像。附属于人像的物像反映了行为人（主要为犯罪嫌疑人）控制支配、携带附着的物品（质）的服饰特征、器具特征、交通特征等情况。挖掘物像的显性或隐性信息,使其成为分析人像,辨识和查缉嫌疑人的依据之一。     

叶片典型工装模块资源库建立和上线服务研究

本文归纳确定了典型叶片工艺中的典型工序,筛选出典型工序所使用的典型工装,通过技术专家和技术骨干,确定出典型工装结构和通用工装元组件结构,由技术人员用UG软件建立三维模型,再把叶片典型通用工装三维模块输入到技术科专人的PDM中的平台,在技术科专人的PDM中的平台上分类和属性标注。使工装结构共享,在今后设计类似工装结构时达到快速反应、提高设计质量。     

基于Gabor特征与支持向量机的字符识别系统研究

利用计算机进行字符自动识别与录入的技术对机器翻译、数据挖掘、人工智能等都有着重要的理论意义和实用价值,基于数字图像处理技术的字符识别是其中的一个重要发展方向。文章重点研究了字符特征提取和匹配识别这两个影响字符识别效果的因素,根据中文字符笔画的方向特点,选择了对图像方向特征敏感的Gabor变换作为特征提取方式,在获取字符的特征向量后,先利用最小距离分类器进行预分类,再利用最小距离分类中产生的候选样本集训练SVM分类器,识别时只需利用候选集分类器依次判决,降低了训练和识别工作量,同时提高了识别效率。实验表明,系统对网站导航字符平均识别率达94%以上,具有一定的理论意义和实用价值。     

基于BIM技术的三维数字化桥梁设计与管理

随着桥梁工程建设的发展,对设计技术水平提出了更高的要求,传统二维设计与管理技术已经难以满足日益复杂的工程设计要求.基于信息技术的桥梁设计与管理系统是行业发展的必然趋势与规律,文章介绍了在基础建设行业兴起的BIM概念,探讨如何基于BIM发展三维数字化桥梁设计与管理技术及其关键技术要点.     

A positive-temperature-coefficient electrode with thermal protection mechanism for rechargeable lithium batteries

A new positive-temperature-coefficient(PTC) material was prepared simply by blending of conductive Super P carbon black(CB) with insulating poly(methyl methacrylate)(PMMA) polymer matrix,which was empolyed as a coating layer on the aluminium foil substrate to fabricate a sandwiched Al/PTC/LiCoO2 cathode.The experimental results from cyclic voltammetry,charge-discharge measurements and impedance spectroscopy demonstrated that the PTC electrode has a normal electrochemical performance at ambient temperature,but shows an enormous increase in the resistance at the temperature range of 80?120℃.This PTC behavior greatly restrains the reaction current passing through the electrode at elevated temperatures,capable of acting as a self-actuating safety mechanism to prevent the battery from thermal runaway.     

人偶（下）

就这么走进大厦？当然不行，这地方是属于私人的。私人企业，一般就意味着麻烦的根源，现在想要进入同样也是一个大麻烦。     

中欧高速公路边(滑)坡稳定性计算与设计差异分析

文章主要研究了某高速公路项目中,中国标准与欧洲标准在边(滑)坡稳定性计算中的差异。在稳定性计算中,国内广泛采用瑞典法和传递系数法,而欧洲标准主要采用简化Bishop法,采用算例计算发现,两种方法所得稳定系数基本一致。而在滑坡推力计算时,采用国内方法所得滑坡推力偏大,计算偏安全保守。在地震工况中,由于欧洲标准同时考虑了水平地震力和竖向地震力的影响,因此所得稳定系数偏小。     

具有极大和次大广义Randi(c)-指数的极值化学树

通过对化学树定义一个新的分类,提出了当αO且n≥9时,具有极大和次大广义Randic-指数的极值化学树就在此分类中,并给出了详细证明.同时,给出了在上述条件下,极大和次大广义Randic-指数的差值.