基于ALOHA的分组动态帧时隙RFID系统防碰撞算法

针对动态帧时隙ALOHA算法在标签数目增大时,时延太大和硬件要求太高的问题,提出了分组动态帧时隙ALOHA算法——GDFSA.该算法通过估算电子标签的数量,根据最佳帧长度对标签进行分组,然后再对标签进行分组识别.实验结果表明,该算法能够有效解决无线射频识别系统电子标签识别时的碰撞问题,提高系统自动识别的效率.     

基于NTRU的RFID安全认证协议研究与设计

为了解决RFID标签数据存储量小、运算能力弱等原因致使通常的密码算法不适用的问题,提出了一种基于NTRU公钥密码算法的RFID安全认证协议。将少计算、高安全的NTRU算法与标签认证协议相结合,对标签ID以及对应的用户信息进行制表编码,对其加密处理并在标签中直接保存密文信息,加入随机数,保证通信过程中的信息都是保密和不确定的,这样不仅解决了隐私泄露、重放攻击等安全问题,并且实现了阅读器与标签的双向认证。     

基于RFID的餐盘自动结算系统

如今全国各大企业与各大高校的食堂都出现就餐高峰时结算餐费缓慢和人工结算失误等问题,因而设计出一套快速且准确的餐费自动结算系统是极为重要的。文章基于RFID无线射频识别技术设计了一套智能的餐盘自动结算系统,采用了ARM-Stm32作为系统主控板、RFID作为识别技术、TFT-LCD作为显示模块等,选用二进制树算法作为RFID无线射频技术防碰撞的主要算法,最终系统通过射频识别餐盘的数量与类型计算出就餐的费用,从而实现餐费的无人自动结算等功能。用户可在开发板上查看就餐餐费、一卡通个人信息及余额情况,最后用户只需刷一卡通完成支付。     

大型超市迫切需要射频识别标签

RFID标签(射频识别标签)是利用无线电波在一定频率范围内识别物体的技术。通过装在标签上的芯片对单个物体进行识别,芯片中整合的天线可将存储的信息传输到阅读器。超市连锁店和百货公司对RFID标签技术在其营业范围内作为所谓的“商品电子代码”有浓厚的兴趣,因为这种技术可以随时随地告诉你,有多少用RFID识别的包装放在哪个售货架上,使得在营业过程中对流通中的商品进行分析和优化成为可能。     

基于RFID系统的改进Q值防碰撞算法

射频识别系统中UHF阶段的Q值防碰撞算法,利用参数Q值的变化动态地改变识别帧中的时隙数,以获得更高的识别效率。基于此算法,本文提出了一种改进算法。在识别帧开始时,引入一种连续碰撞检测机制,对识别标签数量进行预测,迅速地调整出最佳的Q值。通过仿真实验,系统的效率得到了提高。     

RFID射频识别技术对家庭备忘产品设计的影响

随着近些年来科学技术和物联网概念的飞速发展,RFID射频识别技术应运而生。R FID射频识别技术的原理是通过将标签转化至读写器,技术目的是用来识别目标和追踪目标。当下,R FID射频识别技术多用于门禁,物流管理,物品防盗等,将家庭备忘产品设计与RFID射频识别技术进行完美结合,将会使人们的生活更加方便,减少焦虑感。本文就RFID射频识别技术对家庭备忘产品设计的影响展开讨论,深入发掘其在设计中的应用,充分发挥RFID射频识别技术自身的优势。     

基于单次索引机制的RFID防碰撞算法

针对目前的二叉树算法传输时延大、冗余数据多等问题,提出了一种基于单次索引的SI算法.该算法阅读器寻呼时只发送单个碰撞位的索引值,标签接收到这个索引值后进行译码得出碰撞位的位置.仿真实验表明,SI算法在传输时延和数据冗余方面的性能要优于其他二叉树算法,更适用于标签数量较多的场合.     

RFID标签天线的印刷解决方案

RFID即无线射频识别技术，是一种非接触式的自动识别技术，它通过射频信号自动识别对象并获取相关数据，识别工作无须人工干预，可在各种恶劣的环境中工作。20世纪80年代，随着大规模集成电路技术的逐步成熟，RFID系统的体积大大缩小，使得RFID技术进入了实用化阶段。与此同时．多种RFID标签频繁亮相，这也表明人们关于RFID标签天线的制作研究工作已进入了一个崭新的阶段。本文将对RFID标签天线的多种印刷解决方案加以阐述．     

纵观RFID技术

世界各地都在关注射频识别标签RFID（电子标签）技术，并预测它的增长趋势。RFID标签真的能取代条形码吗？下面我们就来分析一下RFID技术及其利弊。     

纵观RFID技术

世界各地都在关注射频识别标签RFID(电子标签)技术,并预测它的增长趋势.RFID标签真的能取代条形码吗?下面我们就来分析一下RFID技术及其利弊.     

Mapping of RFID tag readability in relation to the food content in a refrigerated sea container at 915 MHz

Perishable foods are extremely sensitive to temperature abuse often observed during sea transportation, which regularly involves long transit times. The goal of this study was to compare the effects of the cargo on RFID (radio frequency identification) tag readability to achieve real-time temperature monitoring. A 12 m long refrigerated sea container (68 m³) and a 915 MHz RFID system were used. The container was loaded three times with different food products: canned vegetables, fresh meat and frozen bread. Each load was instrumented with 42 RFID tags evenly distributed throughout the volume. Results showed that canned vegetables provide the best readings (97.6% of tags read), followed by fresh meat (61.9%) and frozen bread (57.1%) respectively. These results validated that radio waves at 915 MHz are absorbed by high water as well as ice contents. However, spacing between metal surfaces and tags can allow excellent RFID readability even if RF reflects on metallic surfaces.

Industrial relevance

The food industry is facing great challenges when it comes to food transportation and distribution. Marine transportation is a slow operation that can expose shipments to a significant range of non-ideal temperatures. Refrigeration units may experience failure during shipment, which inevitably causes losses in quality. The implementation of a real-time temperature monitoring system within a container can provide a good tool to address this issue. Radio frequency technology definitely offers additional benefits such as real-time monitoring as well as tracking and tracing.     

刺绣型超高频织物电子标签的开发

为开发穿戴舒适、形式隐蔽、应用便捷的柔性电子标签,文章以70D/24F×3镀银导电纱为基材将标签天线绣制在纯棉机织物上,并与标签芯片封装制得刺绣型织物电子标签,进而研究各刺绣工艺参数对织物电子标签电阻和读取性能的影响。结果表明:针迹类型、针迹间距、针迹长度等刺绣工艺参数分别通过改变导电纱与电流传输方向夹角、导电纱密度及落针点数量,影响织物电子标签性能。标签天线的适宜刺绣工艺参数为针迹间距0. 25~0. 40 mm、针迹长度2. 0~4. 0 mm的直线针,尤其当采用针迹间距0. 35 mm、针迹长度2. 0 mm的直线针时,织物电子标签读取距离最远可达7. 6 m。     

GS1牛肉全程质量追溯系统框架研究

GS1 是EAN/UCC 的新名字,由编码体系、可自动识别的数据载体和电子数据交换标准组成的全球统一标准。本文基于GS1 标准,针对“源头”追溯、标准化、动态数据共享等难题,搭建了牛肉全过程质量追溯系统的通用框架。框架中个体标识采用RFID 耳标与EAN/UCC 条码,RFID 耳标编码采用EPCglobal 标签数据标准;各流通环节的信息服务器采用三层架构：访问层、业务层、资源层,异构分布架设,以HTTP/SOAP 协议提供用户访问接口;采用信息发现服务结合对象名服务,定位动态分布的信息服务器,实现动态数据共享。     

Overview of RFID Technology and Its Applications in the Food Industry

ABSTRACT:  Radio frequency identification (RFID) is an alternative technology with a potential to replace traditional universal product code (UPC) barcodes. RFID enables identification of an object from a distance without requiring a line of sight. RFID tags can also incorporate additional data such as details of product and manufacturer and can transmit measured environmental factors such as temperature and relative humidity. This article presents key concepts and terminology related to RFID technology and its applications in the food industry. Components and working principles of an RFID system are described. Numerous applications of RFID technology in the food industry (supply chain management, temperature monitoring of foods, and ensuring food safety) are discussed. Challenges in implementation of RFID technology are also discussed in terms of read range, read accuracy, nonuniform standards, cost, recycling issues, privacy, and security concerns.     

Application of RFID technologies in the temperature mapping of the pineapple supply chain

Current temperature tracking systems lack the convenience and accuracy demanded by the real conditions of a fast-paced produce supply chain. In recent years RFID technology has been suggested to be an enhanced method for temperature tracking because of its many benefits, such as using little instrumentation, offering the quick readings necessary for real-time decision making, and allowing the capture of long-duration temperature profiles. However its limitation lies in that probeless systems fail to provide accurate temperature readings in some of the critical points of the pallet and the load. The objective of this work was to study the use of RFID in temperature monitoring by comparing the performance of RFID temperature tags versus conventional temperature tracking methods, as well as RFID temperature tags with probe versus RFID temperature tags without probes and their utilization along the supply chain. Therefore, the temperature mapping of a shipping trial comprising pallets of crownless pineapples instrumented using different RFID temperature dataloggers and traditional temperature dataloggers and packed in two kinds of packages (corrugated boxes and reusable plastic containers) inside a container was performed. The results showed that RFID temperature tags are analogous with regards to accuracy to the conventional methods, but have a superior performance because they allow quick instrumentation and data recovery, and the possibility of accessing the sensor program and data at any point of the supply chain without line of sight. In addition, the use of RFID tags with probe was justified by its role in determining the efficiency of the pre-cooling operations and low temperature abuse tracking during transportation and refrigerated storage; while the RFID tags without probe proved useful for high temperature abuse monitoring during transportation and refrigerated storage. The creation of a RFID sensor with a probe, able to record both ambient and pulp temperatures simultaneously is suggested. Presented at Food Processing Automation Conference, American Society of Agricultural and Biological Engineering (ASABE), Providence, RI, USA, June 28–29 2008.     

服装企业原材料仓库RFID应用方案研究

在分析服装企业原材料仓库管理业务过程的基础上,指出仓库管理存在盘点工作量巨大、库存数量不准确等问题,结合RFID(radio frequency identification)技术的高速移动物体识别、多目标和非接触识别、环境适应性好等特点,提出在服装企业原材料仓库实施RFID的应用方案。该应用方案由3个部分组成,描述应用系统信息需求的信息方案,说明如何使用标签的方法与过程的标签方案和结合具体业务过程的应用方案。该方案可以给服装企业构建RFID应用系统提供较高的参考价值。     

应用改进遗传算法的自动配棉模型优化与应用

针对配棉工艺具有多约束条件的特点和现有自动配棉的不足,提出将改进的遗传算法应用到线性规划优化求解问题中,通过改进遗传算法的初始种群生成策略、遗传算子和进化收敛条件,将配棉约束条件动态融合到种群进化过程中,在保证配棉约束条件的前提下,兼顾了求解的效率和有效性,以达到对自动配棉进行优化的目的。应用结果显示:用改进遗传算法对配棉模型的求解优于基本遗传算法,且配棉的各项指标值符合生产技术要求,在满足混棉质量的前提下,该方法能指导技术人员对候选棉和库存棉做出更合理的选择,有效降低了配棉成本。     

Technical note: Use of an automated grooming brush by heifers and potential for radiofrequency identification-based measurements of this behavior

Healthy cattle readily use grooming brushes but this behavior subsides when animals become ill. Tracking use of a brush may provide an opportunity for health monitoring, especially if the process could be automated. We assessed how healthy heifers groom themselves on a brush and hypothesized that radiofrequency identification (RFID) could be used to accurately and automatically record this behavior. Angus and Hereford heifers (n = 16) were fitted with 2 ultra-high-frequency RFID ear tags and monitored in groups of 8 while housed in a pen with an electronic brush, video cameras, and 4 RFID antennas. Each heifer was observed for a 6-h period using continuous video recordings, and brush contact was characterized in terms of anatomic region involved (head/neck, trunk, or posterior) and when not touching the brush but within 1 body length of it. The RFID data were collected for the same period and then processed such that intervals of up to 16 s with no detections but contained between 2 recordings were also considered positive (animal in brush proximity). Brush proximity (RFID) was regressed against brush contact duration (video) and the sensitivity and specificity for each individual heifer calculated. Across heifers, the majority of brush use involved the head/neck, although a few heifers demonstrated relatively large amounts of posterior contact, which contributed to false-negative readings when antennas failed to read the ear tags. Furthermore, for the majority of time that animals were near the brush, they were not in contact with it but rather standing or lying nearby, resulting in false-positive readings. It follows that the ability of the RFID system to accurately detect brush contact varied widely across individual heifers (sensitivity 0.54–1.0; specificity 0.59–0.98), with RFID generally overestimating the duration of brush proximity relative to actual time spent in brush contact. The implication is that RFID-based ear tag recording of brush proximity relative to continuous video observations of contact does not yield accurate results in certain heifers and therefore, as currently configured, is not a reliable representation of this type of grooming behavior.