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1.
With the large number of items stored in present-day libraries, locating the exact position of an item is time-consuming. This is true not only for poorly managed libraries, but also for well maintained libraries. In the former case, the problem is rather serious. Even though an item may be somewhere in the library, the fundamental role of the library may not be fulfilled, if a user cannot locate the item. In the latter case, a user still needs to perform a tedious shelf search to locate the item. In the first version of the RFID-based Library Management (R-LIM) system, we attached expensive RFID antennas to every shelf, to acquire localization information about the items. However, the solution was not cost-effective, due to the large number of RFID antennas needed. Therefore, in this study, we propose tag-only aging-counter localization for R-LIM, which does not require shelf antennas to determine book locations. In this more recent version, viz., the R-LIM2 system, we replace expensive antennas with inexpensive RFID tags, which enables us to build an affordable system. By associating RFID tags attached to books with those attached to shelves, via periodic tag scans, we determine the exact location of books. This paper describes the aging-counter localization algorithm developed for R-LIM2, and explains how it can be integrated with other parts of the system to locate a book in a search.  相似文献   

2.
基于RFID的广义物流中的移动智能终端设计   总被引:2,自引:0,他引:2  
将RFID技术和普适计算相结合,应用于广义物流,研究该广义物流的系统框架,并着重描述框架中的终端技术。以博物馆导游系统为背景。终端需实现主动服务、被动服务、RFID读写命令等功能,具备无线局域网、无线实时语音播放、集成RFID读写器等模块。以ARM处理器和嵌入式Linux技术为基础.实现了终端的软硬件设计。终端的设计完成为该系统的搭建迈出了重要的一步。  相似文献   

3.
阳鑫磊  何倩  曹礼  王士成 《计算机科学》2017,44(11):268-272, 283
遥感数据日益增长,大规模遥感数据分发对集中分发服务器构成了巨大压力。充分利用参与下载节点的网络资源,提出并实现了一种支持访问控制的P2P大规模遥感数据分发系统。遥感数据分发系统分为遥感数据管理平台和遥感数据客户端两部分,遥感数据管理平台包含共享分发平台网站、云存储、种子资源服务器和跟踪服务器4个组件,遥感数据各客户端和种子资源服务器构成P2P网络。设计了包括共享分片、分片选择、跟踪器通信等的P2P协议,实现的遥感数据分发系统能够上传遥感数据并自动做种,支持对用户的访问控制。根据用户权限进行下载,各下载节点共享分片,然后基于类Bittorrent协议来加速遥感数据的分发。实验结果表明,实现的大规模遥感数据分发系统的功能完善,在多节点下载时具备良好的并发性能,能够满足大规模遥感数据分发的需要。  相似文献   

4.
We propose a gesture recognition technique based on RFID: cheap and unintrusive passive RFID tags can be easily attached to or interweaved into user clothes, which are then read by RFID antennas. These readings can be used to recognize hand gestures, which enable interaction with applications in an RFID-enabled environment. For instance, it allows people to interact with large displays in public collaboration spaces without the need to carry a dedicated device. We propose the use of multiple hypothesis tracking and the use of subtag count information to track the motion patterns of passive RFID tags. To the best of our knowledge, this work is the first on motion pattern tracking using passive RFID tags. Despite the reading uncertainties inherent in passive RFID technology, our experiments show that the proposed gesture recognition technique has an accuracy of up to 93%.  相似文献   

5.
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。  相似文献   

6.
Since RFID tags are ubiquitous and at times even oblivious to the human user, all modern RFID protocols are designed to resist tracking so that the location privacy of the human RFID user is not violated. Another design criterion for RFIDs is the low computational effort required for tags, in view that most tags are passive devices that derive power from an RFID reader's signals. Along this vein, a class of ultralightweight RFID authentication protocols has been designed, which uses only the most basic bitwise and arithmetic operations like exclusive-OR, OR, addition, rotation, and so forth. In this paper, we analyze the security of the SASI protocol, a recently proposed ultralightweight RFID protocol with better claimed security than earlier protocols. We show that SASI does not achieve resistance to tracking, which is one of its design objectives.  相似文献   

7.
Requesting Pervasive Services by Touching RFID Tags   总被引:2,自引:0,他引:2  
As the vision of pervasive computing gradually becomes a reality, we are seeing an increasing number of services in our everyday environments. We don't just access them at desktop computers but everywhere our activities lead us-using mobile terminals and built-in technology. Although a positive phenomenon, this transition also introduces considerable challenges to discovering and selecting services. The authors propose a general framework for requesting pervasive services by touching RFID tags. Visual symbols communicate to users the objects that they can touch and that activate services. When a user touches such a symbol with a mobile phone, the data stored in the tag and other contextual information related to the situation trigger the requested service. The authors designed a set of visual symbols and implemented the required functionality as component-based middleware. They studied this novel system's usability and user experience. This article is part of a special issue on RFID Technology.  相似文献   

8.
Radio frequency Identification (RFID) systems are used to identify remote objects equipped with RFID tags by wireless scanning without manual intervention. Recently, EPCglobal proposed the Electronic Product Code (EPC) that is a coding scheme considered to be a possible successor to bar-code with added functionalities. In RFID-based applications where RFID tags are used to identify and track tagged objects, an RFID tag emits its EPC in plaintext. This makes the tag inevitably vulnerable to cloning attacks as well as information leakage and password disclosure. In this paper, we propose a novel anti-cloning method in accordance with the EPCglobal Class-1 Generation-2 (C1G2) standard. Our method only uses functions that can be supported by the standard and abides by the communication flow of the standard. The method is also secure against threats such as information leakage and password disclosure.  相似文献   

9.
RFID and privacy: what consumers really want and fear   总被引:1,自引:0,他引:1  
This article investigates the conflicting area of user benefits arising through item level radio frequency identification (RFID) tagging and a desire for privacy. It distinguishes between three approaches feasible to address consumer privacy concerns. One is to kill RFID tags at store exits. The second is to lock tags and have user unlock them if they want to initiate reader communication (user model). The third is to let the network access users’ RFID tags while adhering to a privacy protocol (network model). The perception and reactions of future users to these three privacy enhancing technologies (PETs) are compared in the present article and an attempt is made to understand the reasoning behind their preferences. The main conclusion is that users do not trust complex PETs as they are envisioned today. Instead, they prefer to kill RFID chips at store exits even if they appreciate after sales services. Enhancing trust through security and privacy ‘visibility’ as well as PET simplicity may be the road to take for PET engineers in UbiComp.  相似文献   

10.
Recently, as the Internet service technology has been activated and popularized, digital contents industry is increasingly attracting attention as a promising industry. Digital content is a material or information that appears with the development of information and communication technology. It is represented by a sign character, voice, sound, image and video. This digital content industry has been applied to various disciplines. P2P service model is being used as a new business model in the field of digital contents industry. P2P service model is the most important factor in constructing a collaboration system between users. In other words, as more users collaborate, such as sharing content, contributing computing resources, etc., the network becomes rich in data. In addition, smooth traffic processing can be ensured through contribution of computing power. Conversely, as collaboration between users decreases, the resources of the P2P system become exhausted, which can lead to system collapse. Therefore, this paper developed a system for creative English education for young children. To this end, we designed and developed an English education system that can generate interest by applying augmented reality(AR) and implemented which is based on the P2P network service model. Finally, we provide virtual multimedia education contents using augmented reality and build a system environment applying P2P network service model method. Based on this, we implemented the functions such as learning process, progress check, result feedback between instructor and learner in real time.  相似文献   

11.

Sensors and IoT (Internet of Things), which include RFID (Radio-Frequency IDentification) tags, have witnessed widespread adoption across a wide variety of application domains over the last two decades. These sensors and IoT devices are often a part of distributed sensor networks. As with any distributed processing scenario, there is a need to ensure that these devices provide required security and privacy to the tagged object as well as its bearer. Cryptography has been used to address the security and privacy aspects of RFID tags. Unlike a majority of other IoT devices, the commonly used passive RFID tags are extremely resource-constrained and therefore can accommodate only lightweight operations. Security and privacy concerns still need to be addressed as they remain significant regardless of implementation details. We evaluate RFID-based lightweight mutual authentication protocols that have been recently proposed and identify vulnerabilities.

  相似文献   

12.
随着网格技术的发展和应用的扩展,网格己经从单一的面向高性能计算的计算网格转向为面向服务的商业网格.通过分析对等计算融入网格计算技术.将对等思想和对等搜索技术应用于网格资源管理中,提出了一种新的对等搜索框架.最后设计并实现了一个基于P2P技术的网格系统模型.并详细介绍了系统架构、系统主要组成部分、以及网格系统模型的具体功能实现.  相似文献   

13.
基于P2P协议的文件服务器技术   总被引:1,自引:1,他引:1  
余澄丹  程家兴 《微机发展》2005,15(6):158-160
P2P与传统的互联网构架不同,它不区分连接在互联网上的计算机是Server还是Client。P2P协议对于互联网的发展有着划时代的意义。特别是在信息高速膨胀的今天,随着宽带网和ADSL的普及,普通用户的网速越来越快。然而相比之下使用传统的HTTP协议、FTP协议的文件服务器却因此承受着越来越大的压力。文中分析P2P协议的特点,提出和设计了基于P2P协议的网络文件服务器,该服务器与现在已有的P2P文件服务如Bittorrent,ED2K不同,它可以完全代替FTP在Internet上提供文件下载服务。性能测试显示,这种服务器不但下载速度快、连接数限制,而且对服务器性能的要求也较传统的文件服务器大大降低。使用不算强大的服务器也可以工作的很好。  相似文献   

14.
利用从实际网络获得的数据,提出基于流的P2P网络特性模型。采用图形方法和概述统计识别样本所服从的分布族,使用可视化图形方法和假设检验方法对统计分布模型进行拟合优度检验。分析结果表明,流持续时间的分布模型可以用对数正态分布精确表示,混合对数正态分布可以有效拟合流长和流传输速率分布的分布模型,且P2P应用的流长和流持续时间没有高度相关的关系。  相似文献   

15.
RFID在自动识别技术中扮演很重要的角色,如果许多标签同时向阅读器发送信息.信息之间就会发生碰撞阅读器就不能识别其中的信息,这会影响kFID系统的效率,为了解决这个问题,在ALOHA算法的基础上提出改进的措施.仿真结果表明新算法比传统算法效果更好。  相似文献   

16.
In the current article, we address the problem of constructing radiofrequency identification (RFID)-augmented environments for mobile robots and the issues related to creating user interfaces for efficient remote navigation with a mobile robot in such environments. First, we describe an RFID-based positioning and obstacle identification solution for remotely controlled mobile robots in indoor environments. In the robot system, an architecture specifically developed by the authors for remotely controlled robotic systems was tested in practice. Second, using the developed system, three techniques for displaying information about the position and movements of a remote robot to the user were compared. The experimental visualization techniques displayed the position of the robot on an indoor floor plan augmented with (1) a video view from a camera attached to the robot, (2) display of nearby obstacles (identified using RFID technology) on the floor plan, and (3) both features. In the experiment, test subjects controlled the mobile robot through predetermined routes as quickly as possible avoiding collisions. The results suggest that the developed RFID-based environment and the remote control system can be used for efficient control of mobile robots. The results from the comparison of the visualization techniques showed that the technique without a camera view (2) was the fastest, and the number of steering motions made was smallest using this technique, but it also had the highest need for physical human interventions. The technique with both additional features (3) was subjectively preferred by the users. The similarities and differences between the current results and those found in the literature are discussed.  相似文献   

17.
为解决丢失的贵重物品快速查找问题,本文提出一种支持丢失物品移动查找的社区管理系统框架,在配置了RFID阅读器的手机和携带EPC标签物品的基础上,采用移动计算、增强现实技术,基于SOA架构实现灵活高效的移动交互式失物招领物联系统。本文描述该社区系统的设计理念及关键技术,并探讨提升系统性能、降低用户负担的方法,本系统是对物联网技术实际应用的有益探索,可有效地提升社区生活的舒适度。  相似文献   

18.
随着信息技术的发展,智能化的考勤系统已经成为现代化企业架构的必备设施.设计了一种基于MSP430单片机和TRF7960射频芯片的读卡器,实现了对支持ISO14443A协议无源电子标签的查询和防碰撞算法,读卡距离约8cm,最多允许2张卡片同时读卡.读卡器具有性能稳定、功耗低等特点,结合服务器端系统中间件和Web应用软件的开发,实现了一套考勤系统的完整解决方案.  相似文献   

19.
中小型区域RFID标签的识别通常采用阅读器网路实现,因为只有多阅读器才能静态实现阅读器对所有待识别标签的全覆盖。但这种方法面临阅读器使用成本高,阅读器间碰撞,标签识别率低等问题。为改善上述问题,提出一种运用于中小型区域的单阅读器移动RFID系统性能评估方法,该方法以标签丢失率和全识别圈数作为性能指标,在单阅读器移动RFID系统中对已有的静态防碰撞算法的性能进行评估。实验通过判断当前时隙类型确定阅读器是否成功识别标签,每消耗1个时隙阅读器位置调整一次使得信号区及其区内标签重新确定,直至阅读器结束标签识别任务。仿真结果表明该方法能很好地对各种已有标签算法在中小型区域的RFID标签识别环境中的性能进行有效评估,同时提高RFID系统效率。  相似文献   

20.
自由空间下射频识别系统天线通常等效为戴维南等效电路模型,缺少对环境因素和标签电路中寄生元件的考虑。基于射频识别系统基本原理和天线散射理论,提出了一种改进的真实环境下的超高频射频识别系统二端口网络链路模型。建立了基于虚拟仪器技术的射频识别系统天线链路仿真和测试系统。通过仿真实验,得出了真实环境下的标签吸收功率和通信误码率,验证了环境因素对射频识别系统性能的影响。  相似文献   

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