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关键词： 射频识别技术   轮胎硫化   I2C总线  

摘要： 在轮胎生产过程中硫化是极为重要的工序,轮胎在成形后需置入金属模具并通过加热、加压以及一系列固化程序形成结构完整的轮胎。橡胶作为轮胎的主要原料,其性能测试在轮胎的研制和生产过程中尤为重要。本研究利用超高频射频识别技术开发轮胎硫化温度监测系统,该系统由读取器和测温模块组成。温度检测模块采用I2C总线技术,实现对硫化过程中温度的实时测量并将测量数据存储于芯片中便于后续数据的读取和分析,该系统无需开孔测试硫化模具,有效弥补了传统有限测量方法的不足。

关键词： 导电银浆   水性溶剂   银粉   射频识别   柔性电子  

摘要： 导电银浆主要由银粉、溶剂、树脂和添加剂组成,按溶剂性质可分为水性和油性导电银浆,而前者因绿色环保的特点使其在柔性电子技术领域具有极高的应用潜力。使用控制变量法对比实验,发现溶剂配比及种类不仅能提高银浆的导电性同时影响其干燥速率和烧结温度,其中丙三醇能显著提高银浆导电性、乙醇会提高银浆自然干燥速率;最终确定导电银浆配比为n(银粉)∶n(树脂)∶n(溶剂)=125∶55∶53,水性溶剂的配比为n(乙醇)∶n(丙三醇)=161∶339,该银浆具有高导电性(ρ=2.25×10^(-5)Ω·cm)、粘附性(5B)、优良的综合性及绿色环保等特性,同时可实现RFID的应用。

关键词： 模糊PID控制   RFID定位   巡检机器人   六轮差速  

摘要： 文章针对巡检机器人导航定位与运动控制精度要求,提出了一种基于无线射频识别(Radio Frequency Identification,RFID)定位与模糊比例、积分和微分(Proportional Integral Derivative,PID)的巡检机器人运动控制策略。通过建立六轮差速型巡检机器人运动学模型,对巡检机器人前进与停车状态进行误差分析,设计了基于RFID定位与模糊PID的巡检机器人运动控制策略,选取了0.5、1m/s运行速度及无负载、负载300kg两种情况开展实验分析,经分析该控制策略相较于磁导航+传统PID控制方法准确性更高,误差可控制在1.6cm内,降低了18.4%。结果表明该控制策略的准确性、稳定性均有明显提升,验证了方法的有效性,解决了巡检机器人导航定位与运动控制系统误差大的难题,实现了运动控制的准确性、稳定性和鲁棒性目标。

关键词： 超高频RFID   灵敏度测量   自动调谐   阻抗匹配   共轭匹配  

摘要： 灵敏度是衡量无源UHF RFID芯片性能的关键指标,传统测量通常需要匹配网络或专用天线,方法复杂且易受阻抗失配影响。本文提出一种基于自动调谐的芯片灵敏度测试方法:利用自动阻抗调谐技术在测量过程中动态调整系统输出阻抗,使芯片获得最大可用功率,无需专门设计匹配网络。其中,UHF RFID芯片灵敏度的实验测试是采用矢量网络分析仪(VNA)、自动调谐器、Voyantic Tagformance Pro测试仪等搭建测试平台,样品选取了某主流UHF芯片。该芯片的测试结果发现,在915 MHz下的激活功率约为-14.7dBm,与厂商标称的单端口写入灵敏度(-14.6dBm)相差不超过0.1dB,已在测量不确定度范围内。应该看到,相比手动匹配方法,本测试方案显著提高了测量效率与准确度,并具备良好的可重复性和可扩展性。

关键词： 射频识别   物联网   有源标签   标签盘点   防碰撞算法   盘点准确率  

摘要： 在读写器盘点符合GB/T 28925标准的有源RFID标签过程中,标签使用8位随机数RN8作为一次盘点循环中的唯一标识。然而,当标签数量较多时,产生相同RN8的概率显著增加,不利于读写器实现大量标签的准确盘点。针对该问题,提出了一种能够准确盘点大量有源RFID标签的方法,该方法通过让标签在盘点过程中广播自身RN8和在盘点结束后广播自身收集时隙号Nr,保证盘点过程中RN8和Nr的唯一性,实现读写器对标签的单一化处理和准确盘点。实验结果表明,与改进前的盘点方法相比,该方法可以将盘点准确率提升至99.9%。

关键词： Advanced material   chipless radio frequency identification (CRFID)   greenhouse test box (GTB)   moisture test box (MTB)   multiparameter sensing   performance network analyzer (PNA)   Advanced material   chipless radio frequency identification (CRFID)   greenhouse test box (GTB)   moisture test box (MTB)   multiparameter sensing   performance network analyzer (PNA)  

摘要： This article investigates a low-cost FR4-based 8-bit chipless radio frequency identification (CRFID) tag sensor with a multifunctional sensing application and the operating frequency range for the proposed sensor varies from 800 MHz to 5 GHz. The tag's design is based on a complimentary C-shaped resonator with dimensions 50 x 50 x 0.75 mm(3). A material-based sensing method has been adopted to sense the multiple environmental parameters. Advanced materials such as Kapton HN and graphene are embedded between the gaps of the copper slot and used as dedicated moisture and temperature sensing. The Kapton and graphene were tested through Fourier transform infrared spectroscopy (FTIR) spectroscopy to determine its absorption rate. The method of excitation for the proposed sensor is linear-polarized plane wave excitation. Here, two standardized horn antennas have been used for plane wave excitation. This research work proposes two specific sensor performance measurement setups to sense the environmental parameters: the moisture test box (MTB) and the greenhouse test box (GTB). The sensing is achieved by a maximum frequency shift of 300 MHz. The amplitude, resonant frequency, and variance are three major parameters extracted from the moisture and temperature sensor as a function of frequency. Lorentz second-order polynomial equations are used to fit the nonlinear, frequency variant sensor response to an optimal value along with the variance analysis techniques to interpret the sensing data for extracting the features in the CRFID system. The reversible behavior of the tag sensor on the low-cost FR4 substrate concerning moisture and temperature sensing is a better substitute for the other commercial environmental sensors.

关键词： 微波氨气传感器   频率漂移   温湿度频率补偿   射频识别  

摘要： 畜禽养殖、农产品品质检测以及工业环境等重点行业对有害气体的高精度检测提出了迫切需求。然而,室内环境中温湿度的波动会导致气体传感器出现频率漂移现象,进而影响气体检测精度。针对此类问题,通过电磁仿真分析微带谐振器电磁损耗特性,确定气敏材料最佳涂覆位置,进而提升微波传感器对氨气响应灵敏度,进一步分析微波传感器辐射增益与氨气浓度之间的相关性,结合无线功率传输模型,构建了无线氨气检测系统。基于射频识别检测原理,搭建氨气测试系统,开展了不同温湿度条件下传感器测试实验,分析了传感器输出性能。引入反向传输神经网络温湿度补偿算法,并结合皮尔森相关性分析,对不同温湿度条件下传感器的频率漂移进行分析与补偿校正。试验结果表明,温湿度波动对微波氨气传感器频率漂移具有显著影响,补偿后频率漂移幅度减少了14 MHz,误差浓度低至6×10^(-8),相对误差仅为2%,气体检测精度提升了31.11%。相较于基于反向传输神经网络温度补偿模型和支持向量机温湿度补偿模型,具有更好的补偿效果。综上所述,该研究有效提升了微波氨气传感器在复杂温湿度环境中的检测精度,为高精度有害气体检测提供了更有效的测量支撑。

关键词： Potamodromous fish   Fishway   Ecological continuity   Migration   Telemetry  

摘要： Movements of potamodromous fish are poorly understood, especially in large rivers, because studies often focus on fishway evaluation and diadromous species. Here, we assessed the movements of 808 fish of five potamodromous species (Barbel, Barbus barbus;Common bream, Abramis brama;Nase, Chondrostoma nasus;Asp, Leuciscus aspius and chub Squalius cephalus) over 14 years in a highly anthropized river system, the Rhine River, where hydropower plants were progressively equipped with fishways including RFID antennas. The objectives of the study were 1) to characterize long-term and large-scale individual movement patterns of five potamodromous fish species 2) to assess inter- and intra-specific variations based on quantitative movement metrics and 3) to create a typology of individuals based on their movements. Results showed that, despite high intra-specific variability, the inter-specific differences were strong enough to highlight long-term and large-scale species- specific behaviors. Breams exhibited movements that occurred essentially during spawning migration period and at the reach scale. In contrast, barbels were more active, with more movements outside their spawning migration period, showed more large-scale and downstream movements, and used navigation locks more often than other species. For this species, the maximum distance between the two furthest recorded positions at the basin scale was exceptionally high (max = 155 km). We conclude that potamodromous species undoubtedly perform largescale movements, which are characterized by both species-specific and common features. Therefore, efforts need to be made to better consider their ecological needs and swimming capabilities when planning and designing effective fishways for the diverse range of species that move within river systems.

关键词： antifuses   carbon black   polyethylene glycol   RFID temperature indicators   Thermoresponsive materials  

摘要： Time-temperature indicators (TTIs) play an important role in logistics, supply chain, and inventory management. They indicate a visual signal when the temperature exceeds a predefined threshold. However, TTIs require a manual process of checking each label individually, making their applications time and cost-intensive. Radio frequency identification (RFID) tags can streamline the process with data readily available in digital format. Challenges of RFID-based temperature sensors are the need for a battery and incompatibility with standard readers. In this study, thermoresponsive composites are developed based on acetylene black (AB) and poly(ethylene glycol) (PEG). By mixing two PEG binders having different molecular weights, the resulting composites function as thermal antifuses, irreversibly transitioning from a high resistance (HR) state to a low resistance (LR) state. The optimal composition detects a threshold temperature of approximate to 60 degrees C and shows a large HR/LR ratio of >10(3). Combining the antifuse based on this unique AB/PEG composite with an RFID tag with a tamper detection capability allows the fabrication of a battery-free, passive RFID temperature indicator equipped with a 1-bit non-volatile memory. The device can track the environment of temperature-sensitive items, save the status, and indicate a digital output when a temperature threshold has been exceeded.

关键词： Blockchain   Bayesian theory   Radio frequency identification   Emergency material dispatch  

摘要： When an emergency occurs, it is very important to ensure the efficient and orderly dispatch of materials. It can make the progress of rescue work smooth, avoid material waste, and improve public satisfaction. However, it is difficult for the existing system to judge whether the received message is credible because material demanders may overstate requirements either intentionally or unintentionally. The paper establishes a credit value system for material dispatching based on blockchain technology. The system is of material demanders and utilizes the posteriori information in Bayesian theory to update the credit value. At the same time, radio frequency identification tags are used as the information transfer medium to improve the credibility and efficiency of the system. When establishing the credit value system with Bayesian theory, the paper use MATLAB to calculate and visualize the range of parameter values. Finally, the paper compare the efficiency and cost of the improved material dispatching system with the traditional system and verify the advantages of the model. The results of the analysis show that the improved system has the advantages of high speed, high privacy, distributed computing, high credibility and automatic information flow. It can be further generalized to other complex dispatching scenarios.