基于SAW-RFID的电力电缆温度在线监测技术研究

电力电缆运行温度是反映其运行状态的重要参数,在线监测其运行温度可及时确定电力电缆的局部过热,估计电缆绝缘性能,发现安全隐患。文中在分析对比现有测温方法的基础上,提出了一种基于声表面波射频识别(SAW-RFID)系统的无源无线测温系统,并详细介绍了SAW标签的设计原理,采用RFID测试仪对SAW标签进行了测试。文中通过实验证明了该系统的可行性,并基于该系统对XLPE电缆进行了实验,实验结果表明SAW-RFID系统测温结果与热电偶测温结果基本一致,实现了电力电缆温度的远程实时监测。     

RFID技术在彩电行业供应链中的应用

针对彩电行业发展现状和RFID系统的工作特点,分析了RFID技术应用于彩电供应链管理的优势,详细描述了基于RFID技术在彩电原材料供应、生产制造、库存管理、运输、分拣、流通销售、售后服务及报废回收等节点的应用,实现了彩电供应链整体流程的信息共享,并就RFID实施中的关键技术进行了阐述。     

RFID技术在彩电行业供应链中的应用

针对彩电行业发展现状和RFID系统的工作特点,分析了RFID技术应用于彩电供应链管理的优势,详细描述了基于RFID技术在彩电原材料供应、生产制造、库存管理、运输、分拣、流通销售、售后服务及报废回收等节点的应用,实现了彩电供应链整体流程的信息共享,并就RFID实施中的关键技术进行了阐述.     

[数据建模]智能车间RFID标签有效识别及制造信息自动关联

提出了一种基于电子产品编码（EPC）和自动身份识别（Auto-ID）的智能车间RFID标签有效识别方法。通过对智能车间中制造资源种类的详细划分,在EPC Global编码规范的基础上进一步细分类型和序列号两个自定义字段,得到了车间内部制造资源的RFID编码结构;根据在制品（WIP）的设计信息和生产数据形成工件制造逻辑,进而利用数据库技术实现制造资源信息在群属、空间、时间上的自动关联;最后对WIP的RFID标签和制造信息的自动关联进行了实验,以验证所提出的模型和方法的可行性及普遍性。     

基于SAW－RFID的石油钻具全程动态信息管理系统

通过分析SAW－RFID技术的应用优势，设计了石油钻具全程动态信息管理系统，提高了钻具管理的效率及准确性，可有效地为安全钻井、高效生产提供帮助。     

RFID的工业应用

RFID是一种非接触式的自动识别技术,它通过射频信号自动识别目标对象并获取相关数据,识别工作无需人工干预,可工作于各种恶劣环境。RFID技术可识别高速运动物体并可同时识别多个标签,操作快捷方便。因此在工业生产制造过程,包括物料自动配送、流水线控制等环节RFID都有所应用。本期就RFID在工业上的应用发展话题进行了探讨。     

DDS系统在SAW传感器中的应用

基于声表面波的传感器具有很高的灵敏度、良好的线性，有望在气体传感器中得到广泛的应用．通常情况下，测量电路是由放大器与SAW器件构成SAW振荡器、在SAW器件的表面上的扰动，如气体分子在传感器表面的沉积等因素的影响，使SAW振荡器的振荡频率发生了变化可通过测量频率的变化而求出所要的物理量。讨论了用频率直接数字合成器(DDS)构成的SAW测量电路。     

西门子PLC与RFID读写器的串行通信

以思谷RFID读写器SG-HR-I2为例,研究基于RS-485串口的RFID读写器与西门子PLC之间的串行通信,通过在博途软件中进行硬件组态及软件编程,实现了PLC对RFID读写器进行读取和写入数据的操作,该技术可应用在智能制造、汽车生产等各个领域。     

物联网驱动的SMT车间制造执行系统研究

为了高效利用表面贴装技术(Surface Mounted Technology,SMT),提升SMT设备的使用效率,缩短产品的生产周期,提高生产效率,实现车间的可视化、精细化管控,解决生产计划与车间执行过程无法衔接的矛盾,研究并构建了一种基于RFID技术的SMT车间制造执行系统,在详细分析SMT车间生产流程和业务需求的基础上,基于RFID技术构建了功能模型并设计了体系结构,并对基于RFID的SMT车间数据采集及制造过程监控技术进行了系统研究。最后以广州某电子企业的SMT车间为例,验证了该系统的可行性和有效性。     

RFID技术在企业产品生产线上的应用

规模企业生产线的产品工艺流程随着市场变化不断改变的需求,射频识别（RFID）技术在企业生产线得到应用。简述了射频识别（RFID）技术的应用系统组成和工作原理、生产线使用射频识别（RFID）技术的优点、射频识别（RFID）技术在服装生产企业加工生产线工艺流程中的应用。     

Product–service systems in health care: case study of a drug–device combination

A radio-frequency identification (RFID) system has been considered as one of the most promising systems for information technology (IT) asset management because of its well-developed level of technology, worldwide standards and its lower price than other wireless protocols such as WiFi, WiMAX, and Bluetooth. However, RFID systems for IT asset management in business-to-business (B2B) environments are still limited by several constraints such as readable range, sensor capability, and battery problems inherent in existing RFID technologies. In particular, only few research works deal with asset management in a real office environment. This paper proposes a new way of managing IT assets using surface acoustic wave (SAW)-based RFID technology to solve these problems. To show its effectiveness and feasibility, the proposed approach analyzes RFID tag performance based on an electromagnetic test and measures the readability of SAW-based RFID in an office environment. Experimental results show that one of the most hopeful candidates for managing B2B IT assets is the SAW-based RFID system because of its batteryless passive RFID characteristic, relatively long readable range, its potential and inherent sensor capability, and its expandability compared to other RFID systems. Furthermore, the proposed approach systematically analyzes where to attach RFID tags on IT asset devices considering electromagnetic performance based on ID- and sensor-detecting capabilities, which suggests the most appropriate tag position on the device.     

Optimum cut orientation of piezoelectric substrate and propagation direction of SAW for rotation rate sensor

The effect of Coriolis and centrifugal forces on the propagation characteristics of surface acoustic waves (SAW) on a rotating piezoelectric substrate can be utilized for sensing rotation rate. In this paper, the relationship between SAW phase velocity and the rotation rate of the substrate is analyzed theoretically and numerically based on the coupling wave equations on anisotropic piezoelectric substrate with rotation effect. Partial wave theory and surface effective permittivity method are employed. Using LiNbO₃ as an example, some quantitative results of SAW rotation rate sensor, including free and metalized interfaces between substrate and free space in X-cuts, Y-cuts, and Z-cuts, are obtained. Furthermore, by considering comprehensively SAW rotation rate sensitivity with SAW excitation efficiency and beam steering, the optimum cut orientation of piezoelectric substrate and propagation direction of SAW for rotation rate sensor are presented. The research findings can provide theoretical guidance and simulation basis for the experimental research on SAW rotation rate sensor.     

声表面波与声板波激发特性对比研究

通过沉积在压电基片表面的叉指换能器可在基片上激发出声波。以部分波理论为基础,引入表面有效介电常数方法来对比研究压电基片上激发的声表面波和声板波,并通过实验证明了理论分析方法的有效性。特定切向和传播方向的压电晶体只能激发出一种声表面波模式,而其声板波则具有多种模式,且各高阶模式只有当基片厚度与声波波长之比大于某一特定值时才会出现。随着基片厚度增大,声板波各高阶模式的传播速度和机电耦合系数减小,两种低阶模式的传播速度则趋近于声表面波相应值。受基片背面的电学边界条件影响,其中一种低阶模式的机电耦合系数随着基片厚度增大而趋近于声表面波相应值,另一种低阶模式的机电耦合系数则接近于零。根据上述研究结果可以确定叉指电极激发声表面波或声板波的条件及两种声波之间的关系。
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声表面波气体传感器发展概况

声表面波气体传感器包括采用敏感膜和结合气相色谱两种方式.比较而言,采用敏感膜的声表面波气体传感器体积小、功耗低,但可检测的气体种类少、灵敏度低、存在交叉干扰问题;声表面波与气相色谱联用的气体分析仪灵敏度高、可检测气体种类多、很好地解决交叉干扰问题,特别适合于复杂大气背景条件下的气体成分分析.文中介绍了两类声表面波气体传感器的发展概况.     

声表面波微流控液滴生成技术研究进展

微液滴是一种十分优秀的微反应器,在化学合成、生物检测及细胞研究等领域应用广泛。近年来,声表面波微流控技术发展迅速,在微液滴制备中具有重要应用前景。首先简单回顾了微液滴和声表面波微流控的研究发展历程,然后重点介绍了声表面波微流控液滴生成的工作原理、器件结构、液滴生成过程及工艺参数等;同时介绍了声表面波微流控核壳微液滴的可控生成机理及其制造过程。最后总结并展望了该技术在生化检测、生物3D打印等领域的应用前景。     

声表面波汽车轮胎压力传感器的研究

主要介绍了一种能实时监测轮胎压力的方法,即使用无源、节能、环保及易实现无线传输的声表面波压力传感器,有效地检测轮胎压力。此外,引入了蓝牙无线技术,对无线测量系统的研究有一定的参考价值。     

Dynamic wireless passive strain measurement in CNC turning using surface acoustic wave sensors

Wireless, passive and dynamic surface acoustic wave (SAW) strain sensors are especially advantageous in applications with harsh environments where complex force measurements are required. High frequency multiple axis force measurement during machining processes typically requires state-of-the-art piezoelectric dynamometer technologies. Integrating dynamometers and their associated measurement chains into the machining environment typically requires significant modification to the machine structure. In this paper, SAW sensors were developed for process monitoring operations. Single-axis continuous and interrupted cutting investigations were carried out using the SAW technology installed on cutting tool holders demonstrating high dynamic bandwidth strain measurement. SAW dual-axis oblique cutting measurements were carried out where four SAW sensors were set up as two differential pairs each measuring a single axis of applied force. Improvements in sensitivity and cross-talk compensation has been realised. High-frequency wireless passive realtime process signals are presented from a passive wireless SAW force measurement system successfully integrated into an LT15 Okuma machining centre. The paper aims to present wireless passive SAW technology as a potentially platform changing approach for process and tool condition monitoring applications in the future.     

A technique to measure hydrogen absorption in isolated nanometer structures

We describe an apparatus assembled to measure hydrogen absorption on a monolayer of isolated nanometer scale entities. Utilizing inexpensive and readily available high frequency surface acoustic wave (SAW) sensors we achieve a sensitivity of 4 pg, sufficient to detect hydrogen uptake at less than 1% in nanogram level samples of such entities at room temperature. Results of hydriding rare earth metal nanoparticles and a transition metal-carbon complex measured with 315 MHz SAW resonators are presented. However, the design of our apparatus is general and can be used with a wide variety of commercial SAW sensors.     

Wireless sensor marking and temperature measurement with SAW-identification tags

A wireless sensor marking system based on surface acoustic wave (SAW) identification tags is presented. The proposed solution is compatible with existing measurement systems and can be applied directly in the sensor or by means of a unique sensor identification cable (SIC). The SAW tag operates completely passive, and withstands temperatures up to 400 °C as well as shocks up to 35 000 m/s². It contains a unique serial identification number, which is encoded on the high-temperature stable SAW device by means of metallic reflector gratings. The interrogation unit uses the sensor cable for transmission but is not directly connected to it, thus the identification system can be even used with high impedance measurement equipment, e.g. charge amplifiers. Interrogation is done in frequency-domain based on well-known radar principles and is realized in a low-cost add-on circuit to the existing sensor evaluation circuitry. Furthermore, by simply enhancing the evaluation software, a temperature measurement of the SAW tag itself, and thus often of the sensor or the sensor environment can be done without additional hardware requirements.     

柔性声表面波器件的波模式分析

用反应磁控溅射法在柔性聚酰亚胺衬底上沉积了ZnO压电薄膜,并制备了基于ZnO压电薄膜的柔性声表面波(SAW)器件。制备的柔性SAW器件显示了良好的谐振性能,而且展现出两个波模式:模式0和模式1。当波长为32μm,ZnO厚度为4μm时,SAW器件的模式0和模式1的谐振频率分别为34.4MHz和158.5MHz,对应声速为1 100.8m/s和5 072m/s。模式0为已知的瑞利波,模式1为新的高频模式。沉积了不同厚度的ZnO薄膜制备柔性SAW器件,进一步分析了薄膜厚度对SAW器件和模式1的影响。分析认为该高频模式不是传统硬质衬底上SAW器件产生的Sezawa波,而是S_0兰姆波,并且是有衬底情况下的S_0兰姆波。文中还采用Comsol仿真分析了新的高频模式1的粒子振动位移,结果和S_0兰姆波粒子振动位移一致,从而验证了其为广义兰姆波的正确性。