教学课程资源库 更多>>

关键词： Radio frequency identification (RFID)   Tag anti-collision   Tag movement   Double reader   Cloud computing  

摘要： At present, some existing tag anti-collision algorithms are used mostly in scenarios of fixed number of tags and they perform poorly in tag moving scenarios. Therefore, this paper proposes a double reader tag movement RFID anti-collision method based on suffix, and through the cloud platform based on cloud computing, the supply chain data sharing is realized. Tag moving scenarios usually use a single reader. The proposed employs double reader to expand the recognition range and also to prolong the recognition time, but there is the problem of repeated recognition. This article proposes a suffix-based bit-slot ALOHA (SBSA) algorithm, where this problem is solved and the time-slot is reduced. In view of the problem that a large number of tags entering into the recognition area of readers lead to the reduction of the recognition efficiency. This article proposes a suffix-based tag group bit-slot ALOHA (STGBSA) algorithm, tag grouping and tag estimation methods are proposed. Complexity analysis is deployed in this article, from the perspective of the tag loss ratio and identification efficiency, the performances of various anti-collision algorithms are evaluated and compared with those of the existing methods. The simulation results show that the method proposed in this paper is better than the existing methods.

关键词： ultra-high frequency (UHF)   near field   radio frequency identification (RFID)   broadband cross dipole   antenna  

摘要： A broadband cross dipole antenna for ultra-high frequency (UHF) near-field radio frequency identification (RFID) applications is proposed in this paper. The proposed antenna with two perpendicular coplanar dipoles can identify the tags that placed random perpendicularly to the antenna's surface. A prototype is fabricated and tested for verification. By adjusting the length of one dipole, the broadband characteristic is obtained. Measured results show that the operating bandwidth (S-11 < -10 dB) is about 210 MHz from 852 to 1062 MHz. Meanwhile, a strong and uniform magnetic-field distribution surrounding the antenna is achieved with an interrogation zone of 142 mm x 142 mm.

关键词： RFID   医院被服   全生命周期   数据准确率  

摘要： 利用智能终端快速识别技术,能够全面有效地改善医院被服管理工作。方法:通过在医院被服上缝制射频识别芯片,使用智能终端快速识别被服芯片信息。结果:该系统已成功在我院使用两年时间,并取得了良好的效果。结论:该系统能大幅降低被服丢失率,减少被服的大量积压且有效避免了感染风险。

关键词： Rocky coast   Boulder beach   RFID   Boulder transport  

摘要： Previous studies using unmanned aerial vehicles and remote sensing techniques have provided data on group sediment dynamics and overall mobility of a boulder beach at Oia in Galicia, northwestern Spain. They recorded changes in the location and disposition of hundreds of clasts but were unable to trace the intermittent movement of individual boulders. Radio Frequency IDentification (RFID) sensors were used in the present study to identify and record the long-term trajectories of boulders in this area. Sensors were installed in 80 boulders (mean intermediate axes approximately 55 cm) in September 2016 and were used to locate and record their displacement on five occasions, terminating in December 2019. Although burial and other factors prevented data being collected from every tagged boulder during these periods, recovery rates ranged from approximately 50%-75% of the original population. There was considerable variability in the displacement of the boulders, with maxima of >20 m and mean values >5 m. The distance of travel tended to decrease during the course of this study, despite a corresponding increase in storm frequency and intensity. Patterns of movement, including transport distance and direction were essentially chaotic in nature, reflecting the complex interaction and compound effect of a multitude of controls related to such factors as the location of boulders on the beach, their relationship to surrounding boulders, including the effects of sheltering, interlocking, and burial, and their size, shape, and other physical characteristics. The unpredictable behaviour and high transport thresholds of boulder beaches are in contrast to sand and gravel beaches that are characterized by more uniform and predictable patterns of sediment transport and morphological change. (c) 2020 Elsevier B.V. All rights reserved.

关键词： Partial discharges   RFID tags   Radio frequency   Delay lines   Equivalent circuits   Chipless RFID   partial discharge   metamaterial  

摘要： A vialess passive metamaterial (MTM)-based Quadrature Phase Shift Keying (QPSK) modulated chipless Radio Frequency Identification (RFID) tag is integrated with a partial discharge (PD) sensor with the objective of PD detection and identification. Individual tags with the sensor can be mounted on specific electrical assets to be monitored. When interrogated by an external reader at 2.4 GHz, the tags respond with signals that contain the ID information and the state of the PD sensor. Any PD events detected can be traced back to the respective electrical assets that generate the PD emissions after a time-domain (TD) analysis, which allows prompt corrective action before the further degradation and premature failure of assets.

关键词： RFID sensor   Seedling growth   Physiological characteristics   Management mode  

摘要： Lycium barbarum is a perennial shrub of the family Solanaceae, which is widely distributed in northwestern China. Its fruit is purplish-black when it matures, and it is rich in natural nutrients, such as procyanidins. It is necessary to study the seed germination, cutting seedlings, cultivation management and other aspects of Lycium barbarum. The present paper studied the effects of passive RFID sensor facilities on the growth and physiological characteristics of black fruit goji berries. This paper used a passive RFID sensor to detect and analyse the growth and physiological characteristics of black fruit goji berries. Fruit wolfberry seedlings were taken as the research object, and 1600 seedlings with strong growth were selected, including 800 for the experimental group and 800 for the control group. The experimental group was randomly divided into four groups and distributed to four different regions. The same distributions were used for the control group. The experimental group used a passive RFID sensor to record the growth status of each black fruit wolfberry seedling and timely supplement the nutrients needed for plant growth. The data were saved, and the growth and physiological characteristics of Lycium barbarum seedlings were summarized. The control group used the traditional management mode, and nutritional ingredients were supplemented every quarter. Methods of single variable, mathematical analysis, big data statistics and mathematical statistics were used to summarize and analyse the data and the final harvest. The experimental data showed that the passive RFID sensor facilities had a good monitoring effect on the growth of black fruit goji berries. The degree of fusion between the monitored data and the actual situation reached 98.7%. The experimental data showed that the passive RFID sensor facility had a significant impact on the growth and physiological characteristics of black fruit wolfberry seedlings and increased the yield of black fruit wolfbe

关键词： Liquids   Hidden Markov models   Radiofrequency identification   Antennas   Impedance   Pressure measurement   Liquid pressure   radio frequency identification (RFID)   hidden Markov model (HMM)   impedance matching   double tags coupling   online denoising  

摘要： Liquid pressure measuring is of increasingly importance to promote sustainable operation of civil and industrial equipment. In this paper, a novel approach based on distancemeasurement is proposedby usingRadio Frequency Identification (RFID) and Hidden Markov Model (HMM). Two RFID tags, which interrogated by reader, are mainly used to build a liquid pressure sensing system (LPSS). At the same time, an ultra-high-frequencyRFID chip with self-tuning capability aiming to achieve impedancematching is exploited. While HMM takes pride in its real-time processing and high efficiency so as to make a reasonable prediction of liquid pressure. The feasibility of proposed scheme is verified by double tags coupling circuit design and simulation. Through hardware construction and testing, reliable pressure measurement is achieved in an indoor scenario (0.5cm <= d <= 7cm). Meanwhile, parameter evaluating model (PEM) and sequential estimation model (SEM), which are based on Maximum Likelihood Estimation (MLE) and HMM respectively, have been proposed to achieve online denoising.

关键词： Potentiometric sensor   Iridium oxide   RFID   Screen-printed electrode   Kapton  

摘要： In the last decade, wearable sensors have gained a key role on biomedical research field for reliable health state monitoring. A wide plethora of physics marker sensors is already commercially available, including activity tracker, heart rate devices, and fitness smartwatch. On the contrary, wearable and epidermal sensors for chemical biomarker monitoring in several biofluids are not ready yet. Herein, we report a wireless and flexible epidermal device for pH monitoring in sweat, fabricated by encompassing a screen-printed potentiometric sensor, an integrated circuit, and antenna embedded onto the same Kapton substrate. An iridium oxide film was electrodeposited onto the graphite working electrode providing the pH sensitive layer, while the integrated circuit board allows for data acquisition and storing. Furthermore, a radio frequency identification antenna surrounding the entire system enables data transmission to an external reader up to nearly 2 m in the most favourable case. The potentiometric sensor was firstly characterised by cyclic voltammetry experiments, then the iridium oxide electrodeposition procedure was optimised. Next, the sensor was tested toward pH detection in buffer solutions with a near-Nernstian response equal to-0.079 +/- 0.002 V for unit of pH. Interference studies of common sweat ions, including Na+, K+ and Cl-, showed any influence on the pH sensor response. Finally, the integrated epidermal device was tested for real-time on-body pH sweat monitoring during a running activity. Data recorded for a running subject were wireless transmitted to an external receiver, showing a pH value close to 5.5, in agreement with value obtained by pH-meter reference measurement.

关键词： Moisture   Antennas   Slabs   Radiofrequency identification   Intelligent sensors   Internet of Things   Diaper moisture sensor   Internet of Things (IoT)   passive RFID (Radio Frequency Identification)   UHF (Ultra High Frequency) RFID tags  

摘要： Low-energy battery-less passive RFID (Radio Frequency Identification) tags will be an integral part of the upcoming IoT (Internet of Things) revolution. Applications for such tag-systems include medical applications, inventory management, security, localization, household application, etc. Currently, there is a growing demand for passive RFID-based diaper moisture sensors in the market. The target populations for such technology include infants, disabled individuals, and senior citizens. The goal of the moisture sensor is to eliminate the risks related to infection and other issues caused by the failure to remove a wet diaper in a timely manner. Desired characteristics of such a sensor include low cost, easy integration, good dynamic range in sensing metric, a long read range, as well as being comfortable to the wearer. We propose a passive UHF (Ultra High Frequency, 902-928 MHz) RFID-based diaper moisture sensor that is low-cost, user-friendly, reusable, washable, environment-friendly and comes with an extended on-body read range of 3.6 meters with baby diapers and 4.4 meters with adult diapers. The external reader unit is connected to the internet or a local network, and will automatically notify the parents or caregivers as soon as the presence of moisture is detected.

关键词： Unmanned aerial vehicle   PHysically Uncloneable Functions   Fuzzy extractor   Realistic anonymous authentication  

摘要： Advantages of Physically Uncloneable Functions (PUFs) have led to appearing a substantial number of novel identification and authentication based systems such as Radio frequency identification (RFID), which is expected to replace the conventional bar-code identification system due to its advantages such as real-time recognition of a considerable number of objects. For example, RFID can be used to identify an unmanned aerial vehicle (UAV) when it is attached with a tag. In this article, we propose a novel anonymous authentication scheme for RFID-enabled UAV applications using Physically Unclonable Functions. Security and the performance analyses demonstrate that our proposed scheme is secure and efficient. Hence, it can be useful for several RFID-based secure application systems.