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关键词： 物联网技术   物流仓储   RFID技术  

摘要： 阐述物联网技术在物流仓储中的应用特点,探讨物流仓储中的物联网技术应用,介绍物联网技术在物流仓储中的应用场景、物流仓储中的应用案例、物联网技术对物流仓储的影响与效果。

关键词： 动作识别   格拉姆角场   多维注意力   MobileNet   相位信号   轻量化网络  

摘要： 针对基于射频识别(RFID)的相位(Phase)信号的动作识别技术识别精度不高或不够轻量化等问题,提出基于RFID的轻量化的动作识别方法。该方法通过格拉姆矩阵将一维数据转化为二维图像,将Phase转换为格拉姆角场作为改进的MobileNet网络输入,通过格拉姆角场图像所拥有的高阶信号描述能力表现更多的几何性质和内在数据结构,在减小异常数据对识别效果影响的同时提高识别性能并充分利用网络。同时,将坐标注意力机制融合压缩激励机制,获取相位信号中更丰富的上下文信息使模型更好地定位和识别目标,同时在保证不影响识别精度的情况下重新构建网络,减少模型参数以及所需计算量。该方法与传统MobileNet相比,模型参数量仅为原模型的12.9%,同时识别率提高2.34%,每秒浮点运算次数也优于原模型。实验结果表明,该模型各个指标都表现出更优的实验结果,能够完成动作识别的相关要求。

关键词： RFID   security   privacy   DNA   authentication  

摘要： Radio frequency identification (RFID) technology has seen rapid expansion in recent years, used in a variety of applications like tracking, monitoring, ticketing, supply-chain management, contactless payments, etc. Several researchers have recommended elliptical curve cryptography (ECC) as a great cryptosystem to pair with RFID technology to increase security and privacy. However, RFID systems have major problems with insecure communication routes, which pose security concerns. In this research, a DNA TRIKKY based security mechanism has been proposed for RFID protocol to mutually authenticate the RFID tag and reader through insecure channels. The proposed solution uses a sponge structure and DNA-XOR to enhance the hash function generation process, preventing sensitive data from being leaked from the backend server. Informal security evaluations provide proof that the proposed method can withstand many attacks. According to performance evaluation, the proposed method performs better than the current protocols, making it ideal for use with RFID systems since it necessitates less processing time, communication costs, and storage costs particularly for the tag. According to the results, the proposed authentication paradigm works well with RFID tags that have limited resources. A comparison of the proposed protocol to other protocols shows that it performs more securely. Studies have found that this method outperforms other existing strategies.

关键词： 氨气   无源检测   无线传感器   畜禽环境   RFID标签  

摘要： 氨气是畜禽场景中的主要有害气体之一,针对有源传感器不适于电路有线连接受限的畜禽场景问题,该研究基于高频电磁仿真软件(high frequency structure simulator,HFSS)设计了无源传感器仿真模型,选择聚酰亚胺(polyimide,PI)作为基板材料,采用丝网印刷技术研制了基于射频识别(radio frequency identification,RFID)原理的无源氨气传感标签。通过对氨气无源检测原理的解析,选择了具有高表面积的碳纳米管作为氨气敏感材料,推导了通过测量射频接收功率变化实现无源检测的数学模型;考虑谐振频率的动态调整,无源RFID传感标签采用开口间隙可调的裂环谐振器结构,通过分析传输系数的变化对RFID传感标签的检测过程进行模拟;搭建了用于实验室和畜禽场景氨气检测的射频测试系统,围绕功率反射系数、谐振频率、传输系数开展测试分析。试验结果表明,该标签检测效率易受到到二氧化碳、温湿度因素的影响,由于人工切割、基板变形、环境干扰等因素,实物标签的谐振频率与2.4 GHz的仿真谐振频率之间存在0.05 GHz左右的偏差,传感标签的灵敏度约为15 MHz·L/mg,最大阅读距离为24 cm,相比于商用氨气传感器,该传感标签在使用寿命、响应时间方面有明显优势。研究结果为畜禽场景的氨气无源检测提供了有效的理论和实践依据。

关键词： RFID technology   Composite material   Temperature and humidity sensor   LC resonant antenna  

摘要： Due to its convenience and affordability, chipless RFID technology has become increasingly popular for detecting environmental temperature and humidity. This paper presents a wireless chipless RFID sensor for measuring temperature and humidity. The sensor utilizes a composite material consisting of Fe 2 O 3-Co 3 O 4 ,SnO 2 ,and rGO to achieve accurate detection of both temperature and humidity. We investigated the change of RFID resonance frequency under different temperature and humidity variations. The temperature and humidity sensitive material is coated on the surface of the antenna by spinning coating machine. The combined structure of nanoparticle-attached rods of Fe 2 O 3-Co 3 O 4 , granular clusters of SnO 2 and flakes of rGO enhances the sensor 's sensitivity to temperature and humidity measurements. The sensitivity of the temperature and humidity sensor is approximately-0.293 MHz/ degrees C and-2.12 dB/ degrees C during a change in ambient temperature from 10 degrees C to 85 degrees C, and approximately-2.11 MHz/ degrees C and 0.19 dB/%RH during a change in humidity from 10 %RH to 65 %RH at normal ambient temperature. The response time of the temperature and humidity sensor to temperature and humidity changes is 15.3 s and 10.1 s, and the recovery time is 21.7 s and 17.5 s, respectively. The wireless chipless RFID sensor has good sensitivity and responsiveness for temperature and humidity measurements.

关键词： Resonant frequency   Codes   Location awareness   Antenna measurements   Horn antennas   Encoding   Time-frequency analysis   Chipless radio-frequency identification (RFID)   frequency selective surfaces (FSS)   indoor localization   sub-THz  

摘要： Frequency-coded corner reflectors (CR) have been proposed as an essential component of chipless indoor localization systems at subterahertz frequencies. These tags operate by encoding a notch in the frequency domain of the otherwise stable backscattered power spectrum by a CR. The current state-of-the-art in the WR-3 band (220 GHz to 330 GHz) is based on single notch frequency selective surfaces (FSS), whose maximum number of implementable frequency codes is too few for indoor localization applications. This work proposes the coding of the CR with a single layer FSS implementing two notches, using split ring resonators (SRRs) with two different resonance frequencies. The concept is demonstrated by encoding the response of a 3 cm edge CR with an FSS resonating at 242 GHz and 308 GHz. The tag achieves a maximum radar cross-section (RCS) of 3 dBsqm at 275 GHz. Four more tags are demonstrated by simply varying the radii of the SRRs. It is estimated that this approach can implement up to 15 nonoverlapping codes within the WR-3 band, three times more than the state-of-the-art.

关键词： Animal welfare   Classification algorithms   Mortality rate   RFID  

摘要： In this study, we explored the integration of machine learning (ML) techniques with feeding behavior (FB) time series data to predict mortality events (animals culled or found dead) in floor -raised broilers. Our dataset included 2,667,617 daily observations for eight FB traits from 95,711 birds across 146 feeding trials. After data cleaning, the class distribution was 93.7 % healthy birds and 6.3 % withdrawn birds (culled or found dead), coded as 0 and 1 respectively. Mortality predictions were made one or three days before the observed events. Time series data for different FB traits were utilized to extract 22 time series features per trait, creating a structured feature dataset (days in the feeding trial + 128 time series features). We compared different ML algorithms: gradient boosting machine (GBM), multilayer perceptron neural network (MLP), logistic regression (LR), random forest (RF), and support vector machine (SVM). Due to the imbalanced nature of the data, we evaluated two sampling strategies: a random under -sampling technique (RUS) and a combined strategy (RUS + SMOTE). Models were assessed using 20 -fold cross -validation and an independent test set. Statistical tests indicated consistent differences in most FB traits between control and withdrawn birds at least 7 days before the event. Features derived from traits like daily feed intake, number of visited feeders, visiting activity interval, and number of meals presented high predictive importance for mortality monitoring in broilers. In the crossvalidation, classifiers achieved an average (standard deviation) of up to 0.87 (0.02) for the area under the ROC curve (AUC) and 0.55 (0.03) for the area under the precision -recall curve (AUPRC). This demonstrated a significant increase in classification performance compared to a no -skill classifier. However, performance dropped notably when extending the prediction window from one to three days in advance. The performance observed in the independent set w

关键词： Radio frequency identification   Passive RFID sensor technology   Nanocomposite material   ZnO/CuO/RGO nanocomposites   Hydrothermal synthesis  

摘要： With the increasing demand for fruits and vegetables in the market, the development of cold chain logistics has put forward higher requirements for the quality of fruits and vegetables in storage. To ensure the freshness of fruits and vegetables during storage and transportation and avoid unnecessary loss, it is necessary to conduct real-time detection of their odor to ensure their quality. Therefore, based on nano-composite materials combined with Radio Frequency Identification (RFID) technology, this paper designs an integrated RFID sensor that can simultaneously detect temperature, carbon dioxide, and ethanol concentrations. The test results show that the sensor has a high sensitivity of 0.25 dB/degrees C, 0.011 dB/ppm, and 0.65 MHz/ppm for detecting temperature, carbon dioxide, and ethanol concentration, respectively. The sensor also uses Printed Circuit Board (PCB) technology to make the sensor base, which has the advantages of low cost, easy portability, and mass production capability. The results obtained evidence that the system meets the requirements of environmental monitoring for fruit and vegetable storage, runs stably, and has a high use value.

关键词： Antennas   Ferrites   Coils   Magnetic cores   Pipelines   Windings   Magnetic fields   Coil antenna   ferrite core   radio frequency identification (RFID)   underground  

摘要： Current underground radio frequency identification (RFID) tags have not been able to meet the detection needs of pipeline burial toward deep areas. To effectively address this issue, in this work, a novel lightweight segmented RFID tag coil antenna with a combined ferrite core was presented. Based on the magnetic flux distributions of a traditional single large-sized ferrite core, multiple small ferrite cores were combined to replace the original single large core, and the arrangement and number of small ferrite cores were determined. Then, by analyzing the relationship between the coil winding mode and the antenna-distributed capacitance, a segmented winding skeleton was designed. To verify the proposed design, three different types of ferrite-core antennas were fabricated and measured. From the experimental results, the clear superiority of the proposed tag antenna, in terms of mass and working distance compared to the current traditional ferrite-core tag antenna, was demonstrated.

关键词： Distance-bounding   RFID   Authentication  

摘要： In distance-bounding authentication protocols the Prover has to prove not only that it is a legitimate participant, but also that it is in a legitimate zone (e.g., in close proximity to the Verifier). Conventional authentication protocols are not designed to deal with the location of protocol parties. Using such protocols in case of RFID systems makes them vulnerable to simple relay attacks, which is a significant threat. Protocols that combine cryptographic mechanisms with technical measurements (e.g., time-of-flight or GPS location of the Prover) are often used to protect against relay attacks. In this paper we analyse existing distance-bounding authentication protocols and propose a new DB-RFID\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathsf {DB \text {-} RFID}$$\end{document} distance-bounding protocol for RFID systems. DB-RFID\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathsf {DB \text {-} RFID}$$\end{document} protocol develops the ideas of the most prominent Swiss-Knife protocol, which protects against a greater number of possible attacks. We also provide an initial security analysis of the protocol and propose a version of the protocol based on Russian standardized cryptographic algorithms.