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关键词： 开关柜   RFID   深度信念网络   极限学习机   故障诊断  

摘要： 为提高开关柜故障诊断的准确性,提出一种基于RFID传感器和深度学习的开关柜故障诊断算法。首先,设计用于采集开关柜电流信号和温度射频识别(radio frequency identification,RFID)的传感标签;其次,采集的信号通过深度信念网络(deep belief networks,DBN)进行深层次特征提取,并将稀疏编码(sparse code,SC)融合到DBN网络中,提高其检测精度;最后,为提高检测速度,采用极限学习机(extreme learning machine,ELM)对特征提取的信号进行分类识别。研究结果表明,相比于其他算法,本文提出的SDBN-ELM故障诊断模型检测精度更高,识别速度更快,其准确率可达99.63%。

关键词： Bumblebee   Navigation   Pollinator   Pesticide exposure   RFID  

摘要： The intensification of pesticide use is believed to be one of the main causes of the global decline in pollinators. The ability to forage resources effectively and return to the colony is crucial for individual eusocial bees and their colonies, and some pesticides are known to disturb this ability. Our study investigated the effects of the most widely used type of pesticide, glyphosate-based herbicides (GBHs), on the foraging and homing ability of the buff-tailed bumblebee, Bombus terrestris (L.) (Hymenoptera: Apidae). We conducted two experiments in which we exposed bees to field-realistic doses of GBH at colony and/or individual levels and observed their foraging activity and the homing ability of displaced bees. We found that 24-h colony-level GBH exposure increased the number of bumblebees' foraging bouts, but it did not affect the duration of bouts or the homing ability. Regarding the homing rate, there was a marginally significant interaction between acute individual-level treatment and release distance from the colony. Even though the negligible impacts of short-term GBH exposure on homing ability are encouraging, the greater number of (possibly unnecessary) foraging bouts after colony-level GBH exposure might be costly for bumblebees.

关键词： RFID   Multi-dimensional integrated sensors   Nano-sensitive materials   Passive RFID sensors  

摘要： In response to the strategic demands of agricultural modernization and food security assurance in China, this study proposes a novel passive RFID sensor system with integrated multi-parameter detection capabilities for light intensity, COQ concentration, humidity, and temperature. The developed device addresses the critical need for multi-dimensional environmental monitoring in precision agricultural practices and agricultural product traceability systems. Through structural optimization using HFSS electromagnetic simulation software and microfabrication via advanced etching techniques, the sensor demonstrates enhanced performance characteristics within specified operational ranges: temperature (5-25 degrees C), relative humidity (0-50 % RH), COQ concentration (800-1600 ppm), and illuminance (700-1900 lx). Experimental results reveal distinct sensitivity profiles across different environmental parameters: 0.02 dB/lx in illuminance detection (500-1900 lx range), 0.019 dB/ ppm for COQ monitoring, 0.31 dB/%RH in humidity sensing, and 0.80 dB/degrees C for temperature measurement. Notably, the sensor exhibits 16.03 dB amplitude variation across the full temperature detection range and 15.68 dB response in humidity measurements. Key advantages of this integrated sensor include low-cost fabrication, rapid response characteristics, and excellent long-term stability. This technological innovation enables real-time, multi-parameter environmental monitoring throughout crop growth cycles, facilitating data-driven precision agriculture management. Implementation of this system shows potential to reduce yield losses by 18-22 % through dynamic environmental optimization, while enhancing nutritional quality of agricultural products by maintaining optimal growth conditions. The proposed solution provides critical technical support for China's agricultural digital transformation and smart farming infrastructure development.

关键词： Image edge detection   Robots   Radiofrequency identification   Calibration   Mobile computing   Radio frequency   Robot sensing systems   Location awareness   Interference   Wire   Boundary detection   Internet of Things   RFID   virtual boundary  

摘要： A boundary is a physical or virtual line that marks the edge or limit of a specific region, which has been widely used in many applications, such as autonomous driving, virtual wall, and robotic lawn mowers. However, none of existing work can well balance the deployability and the scalability of a boundary. In this paper, we propose a brand new RFID-based virtual boundary scheme together with its detection algorithm called RF-Boundary, which has the competitive advantages of being battery-free and easy-to-maintain. We develop two technologies of phase gradient and dual-antenna AoA to address the key challenges posed by RF-boundary, in terms of lack of calibration information and multi-edge interference. Besides, we consider the presence of multipath in the real world applications, model the effect on signals in the dynamic scenarios, and demonstrate the robustness of our phase gradient-based scheme under multipath. We implement a prototype of RF-Boundary with commercial RFID systems and a mobile robot. Extensive experiments verify the feasibility as well as the good performance of RF-Boundary, with a mean detection error of only 8.6 cm.

关键词： Flamingo Search Optimization   gated recurrent unit   Lyrebird Optimization Algorithm   multipath routing   wireless sensor networks  

摘要： Wireless sensor networks (WSNs) are considered a key foundation for high-level Internet of Things (IoT) practices. Moreover, WSNs depend on transmission for data transfer among sink modules and sensor nodes or intermediate points in the system. However, in WSN, there are several interruptions during the transmission of data. Further, storage space, network bandwidth, and processing power are limited, and hence, it is significant to enhance data distribution to improve network performance. Therefore, this paper devised a new approach known as the Flamingo Lyrebird Optimization Algorithm (FLOA) to improve radio frequency identification (RFID)-WSN integrated network lifetime. Firstly, the network topology of WSN-RFID is simulated, and then cluster head (CH) selection is performed by FLOA in terms of multiobjective fitness, namely, energy, network lifetime, and inter- and intracluster distance. Here, FLOA is formed by integrating Flamingo Search Optimization (FSA) and Lyrebird Optimization Algorithm (LOA). After this, the energy-efficient multipath routing is performed by utilizing FLOA, where link life time (LLT) and energy are predicted using a gated recurrent unit (GRU). Furthermore, FLOA attained the maximum performance with network lifetime and energy of 820.11, 0.923 J, and minimum delay of 0.211 s.

关键词： RFID tags   Antenna measurements   Reflection   Scattering   Power measurement   Polarization   Phase measurement   Surface waves   Technological innovation   Stability criteria   Angle measurement   dual circular polarization   hybrid phase  

摘要： This study presents an independent dual-circularly polarized RFID tag and introduces a method for measuring the incident angle between the RFID tag and the reader. The tag, constructed with hybrid phase shift elements, possesses the capability to convert and independently control dual circular polarization. The reflection from left-handed circularly polarized (LCP) waves exhibits a higher monostatic radar cross section (RCS) than those from right-handed circularly polarized (RCP) waves within a certain angle range. The monostatic RCS difference between LCP and RCP depends on the tag incident angle, varying in magnitude as the angle changes. Therefore, the tag's incident angle can be obtained by comparing the measured difference with theoretically predicted values. A nine-element RFID tag was designed and fabricated, and its performance was validated through experiments. Experimental results confirmed significant distinguishability between the scattered LCP and RCP monostatic RCS patterns, aligning with simulated predictions. The proposed tag incident angle measurement method requires only a single RFID tag and a single reader. Additionally, the method is compatible with conventional positioning methods and can serve as an alternative method to enhance stability.

关键词： Temperature sensors   Harmonic analysis   Temperature measurement   Sensors   Power system harmonics   Rail transportation   Schottky diodes   Monitoring   Temperature distribution   Rails   Antennas   harmonic radio frequency identification (RFID)   RFID   railways   software-defined radio  

摘要： Rail temperature monitoring enhances safety and efficiency, but traditional approaches can be expensive, restrictive, or power-intensive. In this article, an alternative solution is proposed, leveraging harmonic tags-passive sensors that can be wirelessly powered and interrogated by a reader device. Operating at frequencies of 2.45 and 4.9 GHz, these harmonic tags modulate the backscattered signal at a higher harmonic frequency using a Schottky diode as a frequency doubler, with the modulation varying according to the temperature measured by a negative temperature coefficient (NTC) sensor. The proposed tag undergoes performance testing, evaluating conversion loss (CL), communication range, and temperature sensitivity across a range of 0 degree celsius-100 degree celsius. Readings were successfully captured at distances up to 2 m. Validation of the solution occurs in an authentic railway environment, demonstrating its feasibility and effectiveness.

关键词： Bistatic network planning   Distributed antenna system   Multi-objective PSO   Modified k-means clustering   Dynamic redundancy elimination  

摘要： Radio Frequency Identification (RFID) network planning (RNP) is crucial for optimizing network performance by setting system parameters. The new bistatic RFID architecture with a distributed antenna system (DAS) offers advantages for the passive Internet of Things (IoT). It separates transmission and reception to minimize self-interference and extend uplink communication range, while using distributed antennas for broader coverage. Bistatic DAS RNP differs from monostatic in various aspects. Monostatic RNP focuses on factors like reader number, location, and power, while bistatic DAS RNP involves more parameters, including antenna and device numbers, locations, and interconnections. Coverage and interference are more complex, and practical planning faces constraints on antenna ports and feeder line length. Consequently, bistatic DAS RFID network planning (BDRNP) problems are novel, complex, high-dimensional, and constrained, making them relatively unexplored and highly challenging. This paper analyzes bistatic DAS RFID network coverage and interference, and proposes a mathematical model for BDRNP problems. A modified multi-objective discrete particle optimization (M2DPSO) algorithm is introduced, incorporating a modified k-means clustering method to group antennas, which ensures satisfaction constraints and reduces decision variable dimensionality from 4|CS| + |CS|2 to 4|CS| to 4|CS| where |CS| is the problem size. Redundant SDRs/carrier emitters are dynamically eliminated based on global best solution set changes. Experimental results show that M2DPSO algorithm significantly outperforms three existing popular algorithms - nondominated sorting genetic algorithm II (NSGAII), discrete particle swarm optimization (DPSO), and multi-objective evolutionary algorithm based on decomposition (MOEAD) - by 265%, 361%, and 726% respectively, in average inverted generational distance (IGD) metrics.

关键词： activity   automated tracking   group living   RFID   social behaviour   social network   sociality   ultradian rhythms   vole  

摘要： Sociality has evolved on numerous occasions, with important fitness benefits and consequences for individuals in group-living species. Despite the prevalence of group living, it remains challenging to study the proximate factors that promote variation in this behaviour. Meadow voles, Microtus pennsylvanicus, vary in social organization in response to seasonal cues in the wild, providing a remarkable opportunity to study mechanisms that support changing grouping behaviour within a single species. In summer, female meadow voles are territorial and maintain exclusive home ranges, while in winter, they live in mixed-sex groups. Laboratory manipulations of photoperiod reproduce seasonal variation in social behaviour in this species, demonstrated by altered short-term dyadic interactions during behavioural tests. To assess changes in group social dynamics, we implemented an automated tracking system using radiofrequency identification technology to monitor free-moving voles housed in long daylengths and short daylengths in multichambered habitats over extended intervals. We developed open-source software to model each animal's position within the habitat and to describe co-occupancy patterns. Photoperiod drove robust and pronounced changes in group social behaviour, recapitulating natural seasonal transitions in the wild. Voles housed in short, winter-like days spent more time in groups, formed larger, more evenly mixed groups and shared a single home-chamber more often than long-day voles. Short-day voles were more active than long-day voles but rested in groups, thus cohabitation was strongly correlated with ultradian rhythms in activity. These metrics of group dynamics will allow more nuanced assessment of the effects of manipulations on social behaviour in voles and other species, as both habitat and software are adaptable for use with other rodents. (c) 2025 The Authors. Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour. This is

关键词： Chipless RFID   Hajj   Printed Chipless RFID   Crowd Management   Frequency Domain  

摘要： This study presents a novel application for deploying chipless RFID tags encoded with famous Hajj pilgrimage words. Inconspicuous, cost-effective, durable, and lightweight chipless RFID tags encoded with famous Hajj keywords of "Al-Safa", "Al-Marwa", "Al-Tawaf, "Bidayat Al Sai", and "Bidayat Al Tawaf" are designed and fabricated. Each keyword is etched using cooper material on the flexible Kapton substrate of 66 mmx 66 mm x 0.1 mm size. The resonance characteristics of each realized tag are analyzed by observing the frequency shift in their backscattered radar cross section (RCS) in the range of 1-10 GHz using CST software. The RCS of each tag provides a unique electromagnetic coding signature to it, owing to their different current distributions. Thus, provides easy, cheap, and durable deployments of such tags for handling and managing large crowds' movements such as during Hajj. The fabricated tags RCS results have very good agreement with simulation results. The integration of proposed chipless RFID technology with Hajj-related keywords can improve pilgrimage experiences with enhanced crowd management using an integrated wayfinding system based on the Internet of Things (IoT) as well as the preservation of historical and cultural heritage.