教学课程资源库 更多>>

关键词： Clustering algorithms  

摘要： This paper proposes a method based on AP clustering and an improved particle swarm algorithm for radio frequency identification (RFID) indoor positioning, called the AP-PSO method. Firstly, an AP clustering algorithm is used to cluster the RSSI values of the experimental region tags with similarity, in order to achieve the division of tagged regions, reduce the search area of the later improved particle swarm algorithm, and reduce the search time. Secondly, the learning factor of the particle swarm algorithm is dynamically adjusted, in order to improve the search ability and convergence speed of the global optimal solution of particles. The experimental results show that the algorithm can effectively achieve RFID indoor positioning of the tags to be measured, with high positioning accuracy and with the algorithm spending less time.

关键词： Wireless sensor   Carbon nanofiber   Oxygen plasma   Iron oxide   Hydrogen sulfide  

摘要： Hydrogen sulfide (H2S) is the richest and stinkiest toxic gas found around coal mines, manholes, and semiconductor industries. However, there are not many studies on H2S detection around various industrial sites using wireless sensors. This study proposes an H2S wireless sensor system that communicates of the reader antenna and the sensor tag using 904 MHz activated radio frequency identification (RFID). The sensor tag is formed through an iron oxide-immobilized multiscale pore contained carbon nanofiber (Fe2O3-MPCNF)-based conductive paste. This wireless sensor tag has a large detection range (0.2 to 100 ppm) at 25 degrees C, is very sensitive to H2S gas (0.2 ppm or less), and is inexpensive to process. In addition, the sensor tag has a long operating range (5-40 cm) and excellent flexibility, and has excellent cycle stability (up to 35 days), making it practical for wearable devices for wireless detection. CO 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

摘要： Attendance information is an important data resource for physical education management in colleges and universities. Based on wireless and passive RFID technology theory, this paper designs a UHF passive RFID radio frequency identification physical education attendance model. The device includes three parts: carrier leakage canceller, radio frequency transceiver, and digital baseband signal processing. In the model hierarchy, the client sends a Web request to the server, and the request information is organized by the RFID document, including information such as the range, scale, and display attributes of the requested map. The Web server modifies the predefined map definition file by parsing the information. In the simulation process, the frequency domain model and baseband complex envelope time domain system of the RF front-end of the reader based on carrier leakage cancellation were built in ADS software and Matlab/Simulink, respectively. The reader front-end and digital baseband signal processing are comprehensively simulated, and the result verifies the function of the whole system. After testing and debugging, it has been proven that the median synchronization number of the signal is 12, the point synchronization number is 29, the input IDB compression point measured by a single tone is 9.6 dB smaller than that of IIP3, and the input IDB compression point measured by two tones is smaller than 14.4 dB, which can promote the informatization process of physical education management in colleges and universities.

摘要： In this paper we present a novel system for the tracing of the semicircle line during the play of a basketball game. One of the difficult decisions for a referee in such a game play is to establish if a player traced the semicircle line during a throw to the basket. A wide range of solutions are focused on the image detection techniques which require a lot of expensive cameras and data processors for the run of the classification algorithms. For the moment none of this image analysis technique are 100% accurate. Our system is built around a mesh of ESP8266 system on chip microcontroller. To each ESP8266 block a set of IR proximity sensors are connected and RFID tag reader. All the players are identified by a unique RFID tag code which will identify the player who traced the line. All the data acquired from the sensors is processed by the microcontrollers and saved into the cloud.

关键词： Radiofrequency identification   Interference   Statistics   Sociology   Optimization   Behavioral sciences   Planning   Radio frequency identification (RFID)   RFID network planning (RNP)   sparrow search algorithm   mayfly algorithm  

摘要： The radio frequency identification (RFID) technology is frequently used for large-scale RFID network planning, which brings thought-provoking RFID network planning (RNP) problems such as the uncertain number of readers, high interference rate of readers, poor economic benefits, and weak robustness. In this paper, we propose a mayfly sparrow search hybrid algorithm with Circle chaotic map and Levy flight, which is named MASSA. MASSA maps out the position of the readers by adding the idea of the mayfly algorithm (MA) into the optimization process of the sparrow search algorithm (SSA). Circle chaos mapping and Levy flight are added in the SSA optimization process and the nonlinear inertia coefficients to balance the relationship between global search and local search. The MASSA is compared with SSA, Improved sparrow search algorithm (ISSA), MA, particle swarm optimization algorithm (PSO), and gray wolf algorithm (GWO). The first part of the experiment uses the CEC2017 test suite to evaluate algorithm performance and analysis strategy effectiveness. The results encourage the application of MASSA to solve RNP problems. In the second part, experiments were conducted with four objective functions of coverage, interference, power, and load balance. Two different experiments were carried out with fixed number of readers and flexible number of readers under random label conditions. Experimental results show that MASSA has good planning performance, better economy, and robustness.

关键词： Humidity   Temperature sensors   Temperature measurement   Sensors   Permittivity   Resonant frequency   Substrates   Humidity sensor   radar   scatterer   temperature   sensor   wireless measurement  

摘要： A temperature and humidity chipless RFID sensor is presented in this paper. The tag ID as well as the two physical parameters are extracted using a traditional chipless RFID tag and interrogation procedure. No specific material, i.e. particularly sensitive to the quantities to be measured, is used for ease of implementation. The method is based on a model which describes precisely the evolution of the scatterer's resonance frequency as a function of temperature and humidity. The materials permittivity (impacted by these two quantities) and dilatation (impacted only by the temperature) are taken into consideration to estimate these two physical quantities independently and simultaneously using only the measurement of the resonance frequencies of two scatterers. Measurements in a controlled environment and in a real environment are achieved showing the potential of this approach for the sensor application. The sensing limitation as well as the possibility of this approach to characterize the temperature and humidity dependencies of unknown materials are also presented.

关键词： RF   Microwave Theory \u0026 Techniques  

ISBN: (数字)9781394164059 ISBN: (纸本)9781786308337

摘要： Chipless RFID Authentication examines the development of highly secure product authentication systems for manufactured products by using chipless radio frequency identification (RFID) technology. The absence of a chip and its compatibility with mass production make chipless RFID an alternative to barcodes. This book discusses how, by using natural randomness inherent to the

关键词： Material flow measurement   Radio frequency identification(RFID)   Point cloud data processing   Particle size   Porosity   Bulk density  

摘要： A methodology incorporating radio frequency identification (RFID) and point cloud data processing to measure the mass flow of bulk material on the conveyor belt in real-time was developed and demonstrated. Specifically, a stereo vision camera was used to collect the point cloud data of the bulk material flow surface in a line-scanning way. Then, applying RFID technology to divide the belt into multiple test segments, the measurement bias caused by the slippage of the speed sensor's friction wheel was eliminated significantly. Meanwhile, a volume flow measurement model which sequentially obtains the bulk material volume on each test segment in a space volume subtraction way was proposed. Then, given the issue that the bulk density of material flow is not fixed in real application scenarios, a determination model to dynamically estimate the porosity of material flow by point cloud processing was developed. Using this methodology, the measurement errors were within 2.2%.

关键词： Chipless RFID   "U" resonator   frequency encoding   PI   flexible  

摘要： Miniaturization, flexibility and high coding capacity design are very important while considering the development of chipless tags. In this paper, a flexible high-encoding capacity chipless radio frequency identification (RFID) tag with a compact structure is designed using Polyimide, a flexible material with high-temperature resistance as the substrate. The tag works in the band of 1.5 similar to 10.5 GHz, the coding density of 4.348 bits/cm(2) is obtained with four alternating nested improved U-shaped resonance structures. Frequency shift coding is realized by changing the structural parameters of the resonator. The production process is simple because only one conductive layer is needed. Because of its flexible and low-cost characteristics, it provides more possibilities for the promotion of RFID technology. A good agreement between simulation and measurement validates the feasibility of the design concept.