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关键词： RFID   NoSQL   Cassandra   Indian Public Distribution System (PDS)   Supply chain traceability  

摘要： Purpose The purpose of this paper is to design a supply chain database schema for Cassandra to store real-time data generated by Radio Frequency IDentification technology in a traceability system. Design/methodology/approach The real-time data generated in such traceability systems are of high frequency and volume, making it difficult to handle by traditional relational database technologies. To overcome this difficulty, a NoSQL database repository based on Casandra is proposed. The efficacy of the proposed schema is compared with two such databases, document-based MongoDB and column family-based Cassandra, which are suitable for storing traceability data. Findings The proposed Cassandra-based data repository outperforms the traditional Structured Query Language-based and MongoDB system from the literature in terms of concurrent reading, and works at par with respect to writing and updating of tracing queries. Originality/value The proposed schema is able to store the real-time data generated in a supply chain with low latency. To test the performance of the Cassandra-based data repository, a test-bed is designed in the lab and supply chain operations of Indian Public Distribution System are simulated to generate data.

关键词： Bit error rate  

摘要： In an ultrahigh frequency (UHF) radio frequency identification (RFID) system, the throughput can be greatly improved by collision resolution on a physical layer when tags collide, and high-performance coding technology can improve the bit error rate (BER) performance of the physical-layer separation. Most of the traditional physical collision resolutions focus on the code with a single subcarrier. This paper pays more attention to Miller code with multiple subcarriers and proposes a novel physical-layer separation method based on the Miller code. In this method, the separated collision signals are multiplied by clock signals with the same frequency as the subcarrier to complete the frequency shift. And then, a coherent demodulation and a low-pass filter are used to remove high-frequency separation noise. In the simulation, the Miller code with more subcarriers has lower BER than FM0 code with a single carrier. Especially when Miller 8 is selected, the separation efficiency and BER performance of the proposed method are 4 dB higher than those of the traditional XOR method at lower SNR.

关键词： Dipole antennas  

摘要： This paper introduces a prototype of a low-energy high-temperature exposure sensor, which is a temperature-sensitive passive UHF RFID tag that bends forward when exposed to warm air. This "Bending Tag" design is based on a simple dipole antenna fabricated from an electro-textile material. The antenna has a 3D-printed substrate, which is constructed from a commercial Thermo Reactive Filament that gets soft when exposed to 50 degrees C for 30 seconds, causing the tag to bend forward and curve. The sensor tag initially has a read range of more than 6 meters throughout the global UHF RFID frequency band. After bending, there is a significant decrease in the read range (to around 2-3 meters), which is caused by the changed backscattered power of the sensor tag. In an office environment, the backscattered power changes from -36 dBm to -43 dBm. The change in a sensor tag-reference tag system as dP% is approximately 70%. Based on these initial results, our bending tag can be further developed to work as a cost-effective low-energy sensor for monitoring high-temperature exposure.

关键词： Radio frequency identification (RFID)   Cloning detection   Dijkstra?s algorithm  

摘要： With the rapid development of the internet of things (IoT), radio frequency identification (RFID) technology plays an important role in various fields. However, tags are vulnerable to cloning attacks because they are limited by size and production costs. A cloning attack fabricates one or more replicas of a genuine tag, which behave exactly the same as the genuine tag and can deceive the reader to obtain legitimate authorization, leading to potential economic loss or reputation damage. Many advanced solutions have been proposed to combat cloning attacks. Existing trajectory-based RFID clone detection methods use historical trajectories for model training. However, the environment of the RFID monitoring area is complex and diverse and changes in real time. The features trained based on historical trajectories cannot effectively adapt to the complex environment. In this article, we make a novel attempt to counterattack tag cloning based on real-time trajectories. We propose the clone attack detection approach (deClone), which can intuitively and accurately display the positions of abnormal tags in real time. It requires only commercial off-the-shelf (COTS) RFID devices, unlike methods based on radio frequency (RF) fingerprints and synchronization keys, which require additional hardware devices or software redesign. According to the experimental results, our scheme improves the detection precision by 16.71% compared with that of the existing trajectory-based detection methods.

关键词： RFID技术   机场   行李分拣系统   优势  

摘要： 随着科学技术的发展,我国的RFID技术有了很大进展,并在机场行李系统中得到了广泛的应用。本文对RFID技术在机场行李分拣系统中工作原理及对比应用优势展开系统深入地分析探讨,充分说明RFID技术为机场、航司开拓市场、提高服务效率所提供的重要理论意义和实践价值。

关键词： Authentication  

摘要： Today, the Internet of Things (IoT) is one of the emerging technologies that enable the connection and transfer of information through communication networks. The main idea of the IoT is the widespread presence of objects such as mobile devices, sensors, and RFID. With the increase in traffic volume in urban areas, the existing intelligent urban traffic management system based on IoT can be vital. Therefore, this paper focused on security in urban traffic based on using RFID. In our scheme, RFID tags chose as the purpose of this article. We, in this paper, present a mutual authentication protocol that leads to privacy based on hybrid cryptography. Also, an authentication process with RFID tags is proposed that can be read at high speed. The protocol has attempted to reduce the complexity of computing. At the same time, the proposed method can withstand attacks such as spoofing of tag and reader, tag tracking, and replay attack. © 2021, CC BY.

关键词： 物联网技术   企业   EPC   射频识别技术  

摘要： 对于目前企业资产信息管理速度比较慢的问题,有相关的专业人士提出,用物联网的方式对内部设备的资产进行管理,其中包含管理的相关流程以及大概的框架,还有逐渐建立起来的资产分析数据库,以及提供给每一个用户可以与资产进行直接交流。计算每个企业内部存在的设备资产空间,并且进行备份与标注,有效提高企业内部设备资产信息化的管理能力。

关键词： Vehicles  

摘要： In this paper, the calculation method of the link travel time is firstly analysed in the continuous traffic flow by using the detection data collected when vehicles pass through urban links, and a theoretical derivation formula for estimating link travel time is proposed by considering the typical vehicle travel time and the time headway deviation upstream and downstream of the links as the main parameters. A typical vehicle analysis method based on link travel time similarity is proposed, and the theoretical formula is optimized, respectively. Then, an estimation formula based on maximum travel time similarity and an estimation formula based on maximum travel time confidence interval similarity are proposed, respectively. Finally, when analysing the fitting conditions, the collected data from urban roads in Nanjing are used to verify the proposed travel time estimation method based on the radio frequency identification devices. The results show that time headway deviation converges to zero when the hourly vehicle volume is more than 20veh/h in the certain flow direction, and there are more positive and negative fluctuations when the hourly vehicle volume is less than 10veh/h in the certain flow direction. The accuracy of the proposed improved method based on typical vehicle travel time estimation is significantly improved by considering the typical vehicle travel time, and typical vehicles on the road segment mainly exist at the tail of the traffic platoon in the corresponding period.