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关键词： multi-channel   pricing   RFID   possibilistic programming  

摘要： The increasing pressure and intensity of world competition in business environments, which is ever-changing, has doubled the necessity of proper reactions by industrial manufacturing organisations and companies. Therefore, this paper proposes a novel design of a closed-loop supply chain with multiple forms of product distribution and collection that aim to maximise profit and social responsibility while minimising delays in delivery and environmental pollution. The proposed model uses two indices, local employment and the number of jobs created, to show the performance of the function of social responsibility. Further, by mentioning pricing and greenness levels for the products in the paper, we formulate customer demands dependent on the price and greenness of the products. Also, RFID technology is considered for every vehicle to reduce time lags during transportation. Besides, the modelling is performed according to a possibilistic mean-absolute deviation approach due to the uncertain nature of some parameters. Eventually, the augmented epsilon-constraint method is utilised to solve and its validation. The results revealed that the proposed model could provide efficient decisions that can be a suitable tool for managers and experts, and it can have extensive application, particularly from a strategic perspective.

关键词： RFID技术   室内定位   接收信号强度   图书定位   标签顺序估计  

摘要： 自2010年以来,我国公共图书馆建设取得积极进展,公共图书馆设施网络体系不断完善,图书藏量不断增长,但是传统的人工操作已经无法快速、高效且准确地完成图书整理、借还、上架、下架等管理工作。随着无线射频技术的不断完善和标签价格的显著下降,将无线射频识别(Radio Frequency Identification,RFID)技术应用在图书领域受到了国内外学者的广泛关注,尤其是以该技术为依托的更具人性化的自助服务模式。本文的主要研究内容包括: (1)本文将RFID绝对定位技术应用于图书定位。为了减小在具有获取位置坐标需求的图书定位场景下的误差,本文提出了一种基于改进k近邻算法与朴素贝叶斯分类(IKNN-NBC)的绝对定位方法。首先,采用多尺度主成分分析法(Muti-Scale Principle Component Analysis,MSPCA)进行数据预处理,减少外在因素的干扰;其次,为了提高定位效率,采用KD树(K-Dimensional Tree)优化k近邻算法,实现快速找到待定位点的k个最近邻标签;最后,为了提高定位精度且减少时间成本,采用IKNN-NBC绝对定位方法,并与其他定位算法进行对比。 (2)本文将RFID相对定位技术应用于图书盘点。为了提高在具有获取位置排列顺序需求的图书盘点场景下的排序准确率,本文提出了一种基于卷积神经网络(Convolutional Neural Network,CNN)的相对定位方法。首先,构建卷积神经网络模型将图书标签的位置排列顺序转换为多组两个标签的左右位置关系;其次,采用插入排序算法得到图书标签的相对位置顺序;最后,讨论了多种影响因素对顺序准确率的影响并进行对比。 (3)针对以上提出的面向图书定位与图书盘点的室内定位方法,本文设计了一种面向智能书架的RFID图书信息化管理系统,搭建了软硬件模型,从图书管理员与借阅者两个角度进行可行性分析,对用户管理、图书检索、图书盘点进行软件设计,对用户管理、图书检索、盘点等进行功能实现与测试。结果表明,该设计能够解决图书整理、借还等单纯人工操作导致的图书查找困难、图书错架、盘点效率低的问题。

摘要： 随着当今社会物联网设备的大规模普及，RFID设备作为物联网较为重要的感知层，受成本限制，很难具备较强的安全性。RFID使用无线通信信道来传输信号，使得攻击者可以对信息进行截取以及仿造接收器对数据进行收集。通过制定用户的隐私方针、对用户信息进行匿名编码、采用混淆算法将用户的私人信息进行加密、以及制定详细的安全管理制度，能够避免攻击者直接获取真实数据。

关键词： Humidity   Antennas   Sensors   Radiofrequency identification   Ultra wideband antennas   Slot antennas   Resonant frequency   Chipless radio frequency identification (RFID)   encoding   humidity sensor   Kapton   sensing materials  

摘要： This article proposed a 3-bit coded chipless radio frequency identification (RFID) humidity sensor that is anti-interference encapsulated. The proposed sensor is fed through a bent microstrip, and the sensing tag includes three split ring resonators (SRRs) as encoding bits and an interdigital-capacitor (IDC) structure covered with Kapton film as the humidity sensor, fabricated in a Rogers RO3003 dielectric substrate. A planar ultra-wideband (UWB) antenna with an operating frequency range of 1.88-6.04 GHz is proposed to be integrated with sensors as receiving and transmitting antennas. The sensor's humidity detection capability is attributed to the enhanced design of the IDC-sensing element, which is covered with a Kapton film whose dielectric constant varies with humidity, causing a change in the electromagnetic field, so that the sensor is capable of detecting small variations in the electromagnetic properties that characterize different humidities. In addition, humidity-insensitive polydimethylsiloxane (PDMS) is used as the encapsulating layer to minimize the interference of humidity on the coding bits and improve the life cycle. The performance of the fabricated sensor was verified using a vector network analyzer (VNA). The VNA recorded a clear frequency shift response at 23%-90% relative humidity (RH), with a humidity sensitivity of 396 kHz/%RH. Experiments were conducted to validate the repeatability, response time, and recovery time of the sensor measurement. The response time is about 60 s, and the recovery time is about 80 s. Through multiple experiments, it has been confirmed that the measurement accuracy can be maintained within the 30%RH-80%RH range. In addition to having an anti-interference encapsulated, the proposed humidity sensor also has several other advantages, including small size, simple fabrication, and low cost. The use of chipless RFID technology to achieve long-term humidity monitoring is of great significance in structural health monitoring

关键词： 无芯片RFID传感器   互补开口环谐振器   极化变换   介电常数  

摘要： 为使用无线方式确定平板材料的介电常数和厚度，本文建模并分析了一种无芯片射频识别（Radio Frequency Identification,RFID）传感器。传感器包括刻蚀在接地板上的两个互补开口环谐振器，以及由传输线连接的两个单极子天线。对传感区域微带线耦合互补开口环谐振器模型进行了建模分析，研究了两个谐振器的谐振频率随被测材料特性变化的规律。通过仿真和数据分析，当被测材料厚度在2.5 mm～4.0 mm范围内时，确定了两个天线间传输零点与被测材料相对介电常数和厚度之间的线性表征关系。分析结果表明，理论上可以通过传感器的雷达散射截面（Radar Cross Section,RCS）传输零点实现被测材料相对介电常数和厚度的表征，相对介电常数相对误差在5%以内，厚度相对误差在10%以内。

关键词： 核酸机器人   射频识别   智能控制   机械臂   三维滑台  

摘要： 随着医疗机器人技术和医学图像处理技术的快速发展,加之新冠病毒疫情背景下对核酸采样操作高效化与安全性的严苛要求,使得提升核酸采样效率、缓解医护人员的工作压力以及最大限度降低交叉感染风险成为当务之急,这为核酸采样机器人的研发与应用提供了社会需求背景,然而,国内外针对便民核酸采样机器人的系统化集成研究较为有限,还存在较大研发空间。为此,本文研究了一种便民核酸采样机器人设备,能够自动化完成核酸采集当中各个环节的工作。 首先本文对便民核酸采样机器人的系统结构及相关技术进行了深入剖析,从特征分析出发,系统研究了该机器人的整体架构,涵盖了核心组件设计、关键技术选取等方面;其次,介绍了受试者身份认证方法,阐述了二代身份证系统的组成原理以及身份证信息数据的收集过程,并加入身份证识别防碰撞算法,保证受试者的身份信息与采样结果关联;然后,创新地提出了一种智能核酸拭子自动剥离设备,从机械结构、自动剥离方法、控制程序等方面阐述其设计理念,集成到核酸机器人设备上;再者,借助深度学习构建了口咽智能识别模型,结合相机标定和手眼标定技术实现了机械臂采样定位,使样本得以顺利采集;最后,设计并实现了一种基于三维滑台的样本存储装置,通过步进电机驱动,实现了样本试管的自动取放、保存、回收、消毒等功能,有效提升了样本管理的自动化水平,避免采集到的样本和机械臂被受到感染。 综上所述,对系统设备各部分进行集成与优化,完成了研发与实物测试,达到了核酸自动化检测功能的要求。通过研究,探索提出了一种便民核酸采样机器人的设计方法,同时为无人化核酸检测提供了一种可行及有效的方法。

关键词： Resonant frequency   Chipless RFID   Sensors   Wireless sensor networks   Wireless communication   Monitoring   Temperature sensors   Chipless radio frequency identification (RFID) sensor   frequency modulated continuous wave (FMCW) radar   Internet of Things (IoT)   passive   structural health monitoring (SHM)   wireless  

摘要： Currently, the reader based on the frequency modulated continuous wave (FMCW) radar used to dynamically interrogate the chipless radio frequency identification (RFID) sensor needs to collect the envelope of the echo signal through the oscilloscope, which entails expensive acquisition equipment and occupies a considerable amount of space. This article introduces a low-cost FMCW reader for the chipless RFID sensor's dynamic interrogation. The reader mixes the received signal with the local oscillator signal and down-converts it into a low-frequency signal, which can be directly sampled by a low-cost analog to digital converter (ADC). Then, the sensor's resonant frequency can be extracted from the amplitude and phase variation of the reader's sampled signal, respectively within a single interrogation signal period. The working mechanism of the reader is analysed theoretically, followed by verification through the simulations performed in the advanced design system (ADS). Hilbert-based algorithms are presented for restoring the amplitude and phase variations of the sampled signal in the time domain. Then, the high-speed reader is employed to wirelessly query a crack sensor, and the measurement results acquired from the reader exhibit excellent concordance with those obtained from the vector network analyzer (VNA), demonstrating the accuracy and reliability of the reader. Combined with the other types of sensors, the reader can easily read information, such as acceleration, dynamic temperature, and humidity, providing massive dynamic data for structural health monitoring (SHM) and showing great potential in Internet of Things (IoT).

关键词： 车载无线通信   卫星通信   4G   5G   蓝牙   Wi-Fi   RFID   NFC  

摘要： 现阶段汽车+互联网已成为汽车的主流配置，其关键基础技术为无线通信技术。无线通信包括4G、5G、卫星、蓝牙、Wi-Fi、NFC等远近场无线通信技术。通过多种无线通信技术的集成应用，汽车的智能网联化进程得到快速发展。由于不同的无线通信技术有着各自的技术特点，在应用时宜根据具体的使用场景选用。本文研究主流无线通信技术的关键特性，为车联网应用提供助力。

关键词： Millimeter wave communication   Solids   Distance measurement   Millimeter-wave   RFID   machine learning   neural networks   CPS   IoT   3D lens   5G   localization   machine learning   neural networks   CPS   IoT   3D lens   5G   localization  

摘要： The rise and progression of the Internet of Things (IoT) have reshaped how devices connect and share information, leading to more intelligent and interconnected settings. In this realm, the incorporation of self-sustaining millimeter-wave Identification (mmID) devices present a compelling opportunity to elevate IoT implementations, especially concerning accurate positioning and monitoring capabilities. In this work, the authors introduce a novel lens-enabled passive mmID tailored for highly accurate localization and precise 2-axis orientation detection. Equipped with a frequency diverse pixel antenna array and integrated with a low-loss 3D lens for improved performance, the mmID demonstrates a peak monostatic RCS of -29.2 dBsm with a -10 dB angular coverage of +/- 55 degrees across all cuts, translating to a solid angle coverage of 2.679 sr about boresight. A theoretical link budget analysis is provided for the lens-based mmID, projecting a maximum reading range of 868 m when utilizing the maximum allotted 75 dBm EIRP for 5G/mmWave frequencies. Employing a proof-of-concept (PoC) reader with 30 dBm EIRP, the proposed system demonstrates highly accurate localization, with a mean error of <2 cm at distances up to 45 m, and utilizes sensitive phase information to achieve an average phase-based ranging error within 1 mm across distances up to 20 m. Additionally, a novel signal processing methodology employing multi-output Classification Convolutional Neural Networks (CNN) is introduced to accurately discern the 2-axis orientation of the mmID, resulting in a mean error of <5 degrees at ranges up to 30 m. By offering superior precision and versatility, the passive mmID solution emerges as a promising advancement for next-generation 5G/mmWave Cyber-Physical Systems (CPS) and IoT applications.