一种改进的RFID标签防冲撞算法

无线射频识别(RFID)技术是无线通讯中一项新的应用,主要利用无线电波来传递或获取各类标签中的资料信息,但在实际应用中却存在标签碰撞的问题。本文针对RFID技术中标签碰撞问题进行了详细的分析和研究,提出了一种改进的基于序列号对时隙数运算的排序算法用于解决标签碰撞问题,通过仿真得到了较好的效果,具有一定的推广意义。     

基于固件的终端位置管理系统研究与应用

现有的终端位置管控方法大多是在计算机外壳粘贴射频识别（RFID）标签进行实时定位。但是,一旦计算机被带离RFID信号覆盖区域,外贴的RFID标签缺乏对计算机的直接管控能力。因此,基于固件技术和RFID技术,提出和设计了基于固件的终端位置管理系统。首先,该系统通过RFID信号划定授权区域,在上电开机阶段,通过固件层实现与RFID标签的交互,仅允许终端在接收到RFID授权信号后才能开机使用;其次,在操作系统运行阶段,计算机需要得到RFID授权信号才能正常使用;再次,通过固件对操作系统中的位置管控软件进行保护,防止管控软件被篡改和删除。在计算机脱离RFID信号覆盖范围,终端中的软件代理将立即捕捉到这种情况,根据安全策略锁定终端或对数据进行销毁。目前已经研制原型系统,对办公区域内30台计算机终端进行位置管理,实现了终端仅在授权区域可正常开机使用,脱离授权区域将立即锁定。     

基于MF—RC530射频识别识读器的设计与实现

1．引言 射频识别（Radio Frequency Identification,RFID）技术是一种利用无线射频方式进行非接触双向通信并交换数据的自动识别技术。最基本的RFID系统由射频标签和识读器组成。     

RFID的应用现状与发展趋势

一、RFID技术的应用现状 RFID是英文Radio Frequency Identification的缩写,即无线射频识别技术。它是一种非接触式自动识别技术。RFID系统一般由电子标签、识读器和信息处理软件系统三部分组成。当标签进入识读器射频磁场时,标签被激发产生感应电流,将标签中储存的信息发射到识读器中,识读器通过解码系统识别标签,并将识别信息进一步传递到信息处理系统进行分析处理。     

PKI技术在RFID标签数据安全中的应用

射频识别技术RFID作为一种新兴的自动识别技术,近年来在国内外已经得到了迅速发展.但由于RFID产品成本的因素极大地限制了RFID的处理能力和安全加密措施,使RFID标签数据比计算机和网络中的数据更容易被非法获取或改写.在分析RFID标签数据在应用中存在的安全隐患的基础上,提出了通过PKI技术解决RFID标签数据安全问题的方法,通过对数据进行加密和签名,可以有效解决标签数据安全问题.     

基于射频识别技术的出租车防伪管理系统的设计与实现

综合运用2.45GHz有源射频识别(RFID)射频识别技术、信息处理技术、通用分组无线业务(GPRS)通信技术、全球定位系统(GPS)定位技术、移动计算与网络技术,设计了出租车防伪管理系统软硬件架构,开发出2.45GHz有源标签和具有识别、定位导航、移动通信功能于一体的信息终端。同时,在分析系统应用模式的基础上,开发出系统上层应用软件。搭建的应用系统测试结果表明：该系统超低功耗工作,标签峰值电流仅2mA;数据实时性高,传输平均延时小于4s;RFID感知终端有效识读距离达到110m,并能同时识读不少于150个标签。     

智慧监狱物联网解决方案

为了提高监狱信息化管理技术,实现“向科技要誓力”的方针,文章将物联网技术与监狱建设相结合,运用RFID标签、传感器、摄像头,分别从身份感知、位置感知、图像感知和状态感知等来实现监狱的智能化建设,从而提高了监狱监管技术和防范水平。     

多径环境下无源超高频RFID定位算法研究

随着物联网技术的发展,无源超高频无线射频识别(UHF RFID)定位技术的应用环境日益扩大。但在室内复杂多径的信道条件下,其定位精度往往由于多径干扰而大幅下降。为此,对多径环境下的无源RFID进行定位误差分析,并根据误差模型提出一种基于多维标度的RFID定位算法。利用阅读器获取参考标签和定位标签的相位差,通过相位差构建参考标签和定位标签之间的距离矩阵,并采用多维标度方法获取定位标签的位置信息。仿真结果表明,在存在较强直视路径的多径环境中,该算法仅使用少量的参考标签即可有效对抗多径干扰。     

基于RFID的医院药品流动管理系统研究

随着物联网技术的不断发展,无线射频识别技术这一方法得到了不断的完善,也已经开始逐步运用到社会的各个方面,但是在药品流通管理方面还不算完善。基于对RFID(射频识别)技术的研究,文中设计了一种医院药品流动管理系统。采用RFID可以实时对医院药品的流动进行检测和查询。由手持设备对RFID标签进行扫描,将信息传递给上位机,最后由上位机进行相应的处理。使用RFID一方面可以唯一标识医院药品,另一方面可以根据所读到的RFID标签对医院药品进行流动检测和查看相应的信息。     

基于RFID技术的婴儿监护系统的设计

RFID以无线射频方式实现多目标、运动目标的识别,在各领域各行业显示了巨大的应用前景。本文介绍一种利用RFID技术设计的婴儿监护系统,该系统根据结合了有源RFID设计的智能防盗标签和部署的专用网络,运用数据库技术和数据分析技术,确定婴儿位置,确保母婴配对,自动记录婴儿护理状况,并联动了门闸报警机制。     

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     

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。     

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.