引入卡尔曼滤波的RFID数据清洗方法

RFID技术现已广泛应用在供应链、制药监管等领域,然而数据的不准确性制约了RFID技术的进一步发展.为提供高质量的RFID数据给高层应用,对RFID原始数据进行清洗十分必要.本文提出一种基于卡尔曼滤波过滤的数据清洗方法KAL-RFID,有效地解决了单个阅读器的消极读和积极读问题以及动态标签跃迁产生的延迟问题.实验结果表明KAL-RFID方法提高了清洗效率,并且得到更准确的清洗结果.     

基于滑动窗口的RFID自适应数据清洗算法

RFID（射频识别）标签阅读器对操作环境的敏感性很高,导致其产生的RFID数据流不可靠,并含有大量的漏读,因此必须要对原始数据进行清洗。设计基于滑动窗口的自适应数据清洗算法,算法使用滑动窗口技术和二项分布模型计算合适的窗口大小,通过窗口子区间的监测结果和标签的状态来动态调整窗口大小。结果显示,在移动环境下本算法比SMURF算法产生的平均错误数少,性能更加优越,准确率和稳定性都有明显提高。      

基于标签速度和滑动子窗口的RFID数据清洗算法

为提高非匀速RFID(Radio Frequency Identification)数据流情形下的数据清洗准确性,在传统数据清洗算法SMURF(statistical SMoothing for unreliable RFID data)的基础上,提出了一种基于标签速度和滑动子窗口的RFID数据清洗方法.该方法考虑到标签速度对滑动窗口调整的影响,依据标签速度动态调整置信度δ,同时进一步划分滑动窗口,对子窗口中的标签数据进行统计采样,并将其与整个滑动窗口的统计采样处理结果联合起来,以及时检测出标签的跃迁现象,从而准确判断标签的运动情况.实验表明,该方法有效地降低了平均错误率和积极读现象的出现频度,提高了数据准确性.     

一种基于动态标签的RFID不确定性数据清洗算法

基于自适应滑动窗口清洗算法SMURF(Statistical sMoothing for Unreliable RFid data)需要手动输入阈值δ,对于静态标签,δ的取值对平滑结果几乎没有影响;对于动态标签,结果会造成巨大的误差。针对以上的缺点,提出一种基于动态标签的RFID不确定性数据清洗算法DSUMRF(Dynamic tags-based SMURF)。另外,SMURF算法主要考虑RFID不确定性数据的漏读和错读,没有涉及到冗余数据的处理。在DSUMRF算法的基础上,提出一种RFID冗余数据清洗框架。对比实验表明,针对动态标签,DSMURF算法具有更好的性能。     

基于布隆过滤器的RFID数据冗余处理算法研究

RFID技术作为物联网领域的关键技术,具有广阔的应用前景。然而RFID设备在读取标签信息时会产生大量冗余数据。因此,RFID数据冗余处理的研究对于减少RFID中间件系统负荷、快速检测出入标签有着重要的意义。之前针对RFID数据冗余过滤的研究往往是单维度、静态场景的简单过滤,无法实现复杂场景下标签的出入检测。因此,本文提出一种名为时间距离布隆过滤器（TDBF）的算法,该算法从时间和空间两个维度进行冗余过滤。与常用的时间布隆过滤器相比,该算法兼顾了RFID标签的读取时间和读取距离,极大的降低了数据的冗余问题。在保证漏读率较低的情况下,极大的降低了数据的误读率。同时该算法支持动态场景中移动标签的冗余过滤,能够较好的满足出入监控需求。     

RFID读写器网络的跟踪算法研究

针对读写器密集分布且位置固定,标签在其读写范围内移动的RFID系统需要对标签进行识别和跟踪的问题,提出一种改进的虚拟路由跟踪算法,对移动的标签进行跟踪,分析当标签同时被多个读写器读取或被读写器漏读时数据出现异常的处理方法。结果证明该算法可减少误差引入的来源,并且在处理异常情况时不受读写器个数的限制,保证当标签被多个读写器同时读取或被读写器漏读时,仍能够对标签进行跟踪,使得RFID读写器网络有较好的鲁棒性。     

一种基于多阅读器数据冗余的高效RFID数据清洗策略

随着RFID技术的发展,RFID的应用越来越广泛.然而,由于RFID硬件设备固有的限制和环境噪声的影响,造成了RFID原始数据的不确定性,使RFID在很多领域中的应用受到限制.现实应用中的部署环境通常由多个阅读器及大量标签组成,而现有的数据清洗算法大多只针对单个阅读器对标签的读取情况进行研究,因此在真实应用中的效果差强人意.本文综合考虑RFID的数据特性、阅读器和部署环境的先验知识以及具体应用中的约束条件三个方面,提出一种更贴近现实应用的基于多阅读器数据冗余的数据清洗策略LC-INFER(Location-Containment Inference):首先基于贝叶斯推理对数据进行初步清洗,其次结合基于物体间包含关系的平滑技术,并考虑约束条件对数据进行二次清洗以提高数据的准确性,最后部署真实供应链应用环境进行实际测试,并用大量仿真数据集进行模拟测试,验证了本文提出的RFID数据清洗算法的准确性及高效性.     

融合RFID和条形码的工业炸药流向信息识别

工业炸药的流向监控是减少公共危害的重要手段,基础就是产品的信息标识与识别;为了解决此问题,提出基于RFID和条形码混合信息标识与识别模式,该模式个体标识采用条形码,批量标识采用RFID技术;利用Globe Class标准与LDAP技术,提出RFID信息获取模型与获取技术;实际应用表明,该模式即充分利用RFID远距离、多标签、大容量的特点,又兼顾遗留系统和条形码低成本优势,而且条形码与RFID标签建立了映射模型,识别准确率达到100%,较好解决了工业炸药全流程动态流向信息识别问题。     

适用于低成本标签的移动RFID认证协议

移动RFID系统中,阅读器与服务器之间的通道安全假设不再成立,针对这种情况,分析了当前移动RFID认证协议的安全及性能问题,建立了移动RFID安全隐私模型;基于该模型,在兼容EPC Class-1 Generation-2低成本标签系统的基础上,提出了一种能够抵抗假冒攻击、去同步化攻击,且提供前向安全隐私保护的双向认证协议;通过安全性证明与性能比较分析,表明该协议达到了设计目的,可适用于较大规模的低成本标签移动RFID系统。     

基于TreeMiner算法的XML文档结构相似度量方法*

提出了一种基于TreeMiner算法挖掘频繁子树的文档结构相似度量方法,解决了传统的距离编辑法计算代价高而路径匹配法无法处理重复标签的问题。该方法架构了一个新的检索模型—频繁结构向量模型,给出了文档的结构向量表示和权重函数,构造了XML文档结构相似度量计算公式;同时从数据结构和挖掘程序上对TreeMiner 算法进行了改进,使其更适合大文档数据集的结构挖掘。实验结果表明,该方法具有很高的计算精度和准确率。     

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.     

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)

正~~     

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