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关键词： RFID   门禁系统   物联网   身份认证   远程授权   多线程  

摘要： 结合数据传输技术(通过WiFi实现数据之间的传输)、物联网射频识别技术、数据库、手机APP开发技术等开发了一套基于RFID的远程授权门禁系统。控制模块对卡进行不同操作编成子程序模块,制定了门禁系统与PC机的通信协议;同时使用Delphi编制了简易的串口调试程序,实现了将PC机的管理信息、应用数据等下载到读写器和将读写器的相关记录上传到PC机。本文阐述了RFID门禁系统的组成、系统的基本工作原理,对身份认证系统和远程授权系统设计做了详细介绍,最后对智能门禁系统行业的应用前景进行了分析。

关键词： rectenna   antenna   rectifier   energy harvesting   radio frequency  

摘要： The omnipresence of connected objects leads to the quasi-permanent presence of electromagnetic waves from different sources in our environment. This article presents a new electromagnetic energy harvesting device, rectenna type, which offers the advantage of being versatile. Indeed, the proposed prototype is compatible with three frequency bands of radio standards widely deployed today (UHF RFID, GSM-1800, and UMTS-2100), and its performances remain good for low to very low ambient power levels as well as for different loads depending on the targeted application. The proposed solution is based on a tri-band antenna with very good efficiency and a bandwidth of at least 80 MHz for each of the operating frequencies. Moreover, the associated rectifier circuit is also tri-band and offers good performance in terms of RF-to-DC conversion efficiency for input levels varying in a rather wide range of power levels. The study is based on a design phase by simulation until the realization of prototypes and their experimental characterization. The designed rectenna is compared with solutions found in the literature.

关键词： IoT   RFID   security   authentication   random oracle model  

摘要： The Internet of Things (IoT) is a future trend that uses the Internet to connect a variety of physical things with the cyber world. IoT technology is rapidly evolving, and it will soon have a significant impact on our daily lives. While the growing number of linked IoT devices makes our daily lives easier, it also puts our personal data at risk. In IoT applications, Radio Frequency Identification (RFID) helps in the automatic identification of linked devices, and the dataflow of the system forms a symmetry in communication between the tags and the readers. However, the security and privacy of RFID-tag-connected devices are the key concerns. The communication link is thought to be wireless or insecure, making the RFID system open to several known threats. In order to address these security issues, we propose a robust authentication framework for IoT-based RFID infrastructure. We use formal security analysis in the random oracle model, as well as information analysis to support the claim of secure communication. Regarding the desirable performance characteristics, we describe and analyze the proposed framework's performance and compare it to similar systems. According to our findings, the proposed framework satisfies all security requirements while also improving the communication.

关键词： Coevolution   Development   Fledging time   Life history   RFID   Survival  

摘要： Transitions between life history stages are fitness-limiting events that depend on environmental and individual characteristics. For altricial birds, fledging from the nest is a critical shift in development with direct impacts on survival, yet it remains one of the most understudied components of avian ontogeny. Even less is known about how brood parasitism affects the fledging process in host nestlings. The prothonotary warbler (Protonotaria citrea) is a host of the obligate brood parasitic brown-headed cowbird (Molothrus ater). We tested whether the presence of parasitic nestlings negatively alters host fledging by experimentally parasitizing nests with a cowbird (heterospecific parasite) or a warbler (conspecific parasite) egg, comparing them to non-manipulated control nests, and monitoring them using radio-frequency identification (RFID) systems. As expected, in heterospecifically parasitized nests, warblers were smaller, fledged at older ages, and had greater overall fledging latency compared to conspecifically parasitized nests. There was no such impact of conspecific parasitism relative to controls. Warbler nestling size predicted the age and order of fledging, with larger nestlings fledging earlier. Nestlings fledging at earlier ages fledged later during daytime hours. Cowbirds and last-fledged, smaller warbler chicks spent the most time in the nest entrance before fledging. Finally, although male warbler nestlings were larger than females, there were no sex effects or effects of extra-pair status on fledging. Our study shows that while conspecific parasitism has no detectable effect on host nestmates, heterospecific parasitism impacts host size and fledging phenology, which may influence post-fledging survival of parasitized broods. Significance statement In many species, juveniles undergo dramatic transitions in lifestyle as they age and become independent. For most birds, fledging from the nest is an important developmental shift, potentially impacted by

关键词： Inertial Measurement Unit   RFID   Finite Mixture Model   Energy-efficient   Precision Livestock Farming   Behavior classification  

摘要： In precision livestock farming, localization and activity sensors are used to detect dairy cows' diseases at an early stage and play a significant role in improving the dairy cows' productivity and welfare. However, these sensors have limitations and must be constantly updated, renewed and improved. Indeed, the localization sensors detect the dairy cows' position without specifying exactly what they are actually doing (overlap, grooming, etc.). In addition, the activity sensors are attached to the dairy cows' legs or heads which limits monitoring several reproductive and morphological events such as muscular contraction, overlap acceptance, etc. To overcome these limits, we have designed a new non-invasive back-attached sensor based on a combination of Inertial Measurement Unit (IMU) and passive RFID network allowing dairy cows' identification, localization and detection of a wide range of activities. The designed classification model is based on Gaussian Mixture Model (GMM), used to individually define dairy cow thresholds allowing discrimination of their activities. The classification model is integrated into a technique based on time-driven system for controlling calculation and transmission. Also, two optimization approaches based on data fusion and temporal sequential appearance of activities were explored. The sensor energy-efficient management was explored using a sleep/wake-up method and the RFID readers localize the dairy cows when they move between feeding, watering, milking and resting zones. The activity synthesis is transmitted with an event-driven approach. The obtained results show that our sensor achieves high overall accuracy rate (99%) with low power consumption (0.05 mA).

关键词： RFID   inductive coupling  

摘要： Though widely used in industrial and logistic applications, current passive Radio Frequency Identification (RFID) technology still has a fundamental limitation: Individual users who do not carry any reader find it difficult to interact with tagged items, such as retrieving their digital profiles and requesting certain associations with them. Recent proposals to improve the user-item interaction experience rely on special hardware, such as a smartphone-based RFID scanner. This work presents a promising approach to allowing each user to interact with a tagged item using only one passive tag, which is named the Tag Mutual Identification Interface (TagMii). TagMii requires a user to put one's user tag in physical proximity with an item tag to express certain interactions between the user and item. The key idea behind TagMii is to utilize two experimental observations: (1) inductive coupling for detecting interaction events, and (2) channel similarity for determining the actual interacting tags. We implement TagMii using commodity off-the-shelf RFID devices and conduct experiments in complex environments with rich multipath, mobility, wireless signals, electrical devices, and magnetic fields. The results show that TagMii provides accurate mutual identification. TagMii is a completely new approach for user-item interactions in pervasive environments and enables many user-friendly Internet of Things applications with low cost and convenience.

关键词： RFID   orientation detection   relative localization   Internet of Things  

摘要： Nowadays, detecting and evaluating the internal structure of packages becomes a crucial task for logistics systems to guarantee reliability and security. However, prior solutions such as X-ray diffraction and WiFi-based detection are not suitable for this purpose. X-ray-based methods usually require manual analysis or image processing algorithms with high complexity, while WiFi-based solutions may fail to detect complex structures due to the significant error of the RF-signal features. In this article, we propose RF-Detector, a low-cost RFID solution for performing three-dimensional (3D) structure detection of items contained in the packages, including the item orientations and relative locations. We thoroughly investigate a brand-new sensing model for RFID-based 3D structure detection, i.e., revolving scanning. We propose not only the fundamental revolving model but also a novel calibration method for the undesired deployments. We have implemented a prototype system to evaluate the performance of RF-Detector. Extensive evaluations in real settings show the effectiveness of RF-Detector, achieving very high accuracy of the internal 3D structure detection.

关键词： Radio -frequency identification   Blood management   Technology  

摘要： Inventorying blood products is an essential process in blood station management. Traditional methods need to integrate barcodes with refrigerators, which suffer from low time efficiency, high error rate and high labour cost. Several methods have been proposed to automate this process in blood stations. However, none of them is ideal enough. In this paper, we analyse the difficulties of automation in blood inventory, and propose an automated blood inventory system based on UHF RFID technology. Comparisons over our method with manual inventory and handheld RFID inventory are conducted. The result shows that our method is nearly 10 times higher than manual inventory in time efficiency while increases the accuracy to 100%. ?? 2021 Soci et e franc?? aise de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.

关键词： Resonators   Scattering   RFID tags   Resonant frequency   Symmetric matrices   Strips   Shape   Chipless RFID tag   cross-polar RCS   orientation-insensitive   polarized   resonator   unit cell  

摘要： Babaeian and Karmakar present a technique for designing resonant scatterers that display a cross-polarization reflection that remains consistent (i.e., non-zero) regardless of the orientation of the target. The authors claim that this property can be obtained simply by duplicating, rotating, and arranging the position of a unit cell. We will show in this comment that all the design techniques presented by Babaeian and Karmakar in Section III lead to multiple cancellations of the cross-polarization component of the backscattered E-field. Therefore, the measurement results presented by Babaeian and Karmakar cannot be justified by the theory presented in Section III of the same article.

关键词： Blockchain   PUF   RFID   Secret sharing   Supply chain security  

摘要： Due to globalization, supply chain networks are moving towards higher complexity and becoming vulnerable to various kinds of attacks such as counterfeiting, information tampering, and so on. Appropriate approaches are necessary to tackle different types of attacks and to ensure the required supply chain security. In this paper, we have addressed the product counterfeiting issue using Physical Unclonable Function (PUF) enabled Radio Frequency Identification (RFID) tag. In this research, as a preferred alternative to the traditional centralized databases, blockchain technology has been leveraged to support anti-counterfeiting. Applying blockchain technology to supply chains can add many useful features such as decentralization, immutability, transparency, traceability, non-repudiation, complicated record-keeping, and so on. We have also used a reputation-based consensus algorithm for the blockchain which is less resource-intensive and thus will not indirectly impose additional cost on supply chain products. In the same research direction, we have devised our system architecture that is suitable for lightweight supply chain devices. The proposed three protocols namely: registration protocol, verification protocol, and transaction protocol along with the blockchain technology help to transfer the ownership of the authentic product and keep the sensitive supply chain information safe. An encryption-based secret sharing technique has also been introduced to assist data protection.