Essential Topics on Constructing WCDS-based Virtual Backbone in Wireless Sensor/Mesh Networks

Clustering or connected dominating set (CDS) both approaches can establish a virtual backbone (VB) in wireless sensor networks (WSNs) or wireless mesh networks (WMNs). Each cluster consisting of a cluster head (CH) and its neighboring nodes can form a dominating set. After some bridging nodes were selected, cluster heads (CHs) connected through these bridging nodes naturally formed a CDS. Although CDS provides obvious backbone architecture, however, the number of cluster heads and bridging nodes may be too large, this may cause the loss of advantages of virtual backbone. When we effectively reduce their numbers, more effectively WCDS (Weakly Connected Dominating Set) can be fining out. Some essential topics on constructing WCDS-based VB in WSN/WMN are discussed in this paper. From the point of view of three different protocol layers, including network (NWK) layer, MAC layer, and physical (PHY) layer, we explore their cross-layer research topics and design algorithms. For NWK layer, area-based WCDS algorithms and routing strategies including via VB and not via VB are discussed. For MAC layer, a WCDS-based energy-efficient MAC protocol is presented. For PHY layer, battery-aware alternative VB selections and sensor nodes with different transmission ranges are addressed.

基于蓝牙Mesh技术的校园绿化浇灌系统设计

调研发现,很多高校对校园绿化管理手段有限,虽投入大量人力、物力,但经济效益差,水资源浪费现象比较突出。基于此,设计了一种以传感器+单片机为终端控制单元、利用蓝牙Mesh组网通信的校园绿化浇灌系统。系统具有组网便捷、覆盖面广、控制灵活、网络健壮性强等优点。实验结果表明:系统在不同的环境因素下,能自主判断植物需求,按照既定策略实施浇灌,系统运行正确率平均达91%。将该系统在高校推广使用,能有效降低后勤运营成本,节约水资源,提高校园绿化养护效率。

蓝牙Mesh网络AODV路由改进算法

蓝牙Mesh网络使用泛洪进行多跳通信,在没有路由机制的情况下,由于消息的连续广播,原有泛洪机制会导致网络开销增大和通信延迟。本文基于能量有效的AODV改进算法E AODV使用MATLAB进行仿真,根据跳数、节点剩余能量、链路质量来选择最优节点进行数据包的转发。仿真结果表明,E-AODV算法可减小蓝牙Mesh网络中RREQ数据包传输数量,通过与传统泛洪、AODV算法比较,该算法能够有效降低数据包传输时延,降低网络能耗,提高网络性能。

基于强化学习的大规模多模Mesh网络联合路由选择及资源调度算法

为了平衡新型电力系统中大规模多模Mesh网络的传输可靠性和效率,该文在对优化问题进行描述和分析的基础上提出一种基于强化学习的大规模多模Mesh网络联合路由选择及资源调度算法,分为两个阶段。在第1阶段中,根据网络拓扑结构信息和业务需求,利用一种多条最短路径路由算法,输出所有最短路径。在第2阶段中,提出一种基于多臂老虎机(MAB)的资源调度算法,该算法基于得到的最短路径集合构建MAB的摇臂,然后根据业务需求计算回报,最终给出最优的路由选择及资源调度方式用于业务传输。仿真结果表明,所提算法能够满足不同的业务传输需求,实现端到端路径的平均时延和平均传输成功率的高效平衡。

软件定义无线Mesh网络多目标路由优化算法

无线Mesh网络(Wireless Mesh network, WMN)中,链路拥塞会导致较长的传输时延和排队时间,因此将链路负载均衡与服务质量结合起来一直是研究热点.本文针对多目标路由优化管理的关键问题,将路由问题表述为整数线性规划(Integer linear programming, ILP)模型,并将无线Mesh网络与软件定义网络(Software defined network, SDN)结合,设计了适应于SD-WMN架构的多目标函数、约束条件以及整体的网络优化模型,此外,由于该整数线性规划模型是NP完全的,本文将改进的人工蜂群的启发式优化算法引入到路由优化算法中,以获得源节点和目的节点之间传输流量的理想路径.本文所提出方法在Mininet网络模拟工具中的仿真结果证明了该算法的有效性,与OSPF、SDNR以及遗传蚁群优化(G-ACO)相比,所提出方法在丢包率、往返时间和负载均衡方面均有不错的改善.

基于蓝牙Mesh技术的酒店客房控制系统设计

针对传统的酒店客房控制系统存在功能单一、布线复杂、扩展性差等问题,提出一种采用蓝牙Mesh组网技术的酒店客房控制系统。该系统采用ESP32系列芯片作为主控制器,通过蓝牙Mesh组网实现客房内部设备之间通信消息的接收和转发,实现了酒店灯光、空调的无线控制和室内环境监测功能。各设备的工作状态数据通过MQTT传输技术上传到云平台,并通过微信小程序实现客房内设备的远程控制。测试结果表明,该酒店客控系统通信正常,并实现了预设功能,具有免布线、功能易扩展等优点。

基于无线Mesh自组网煤矿液压支架压力传感器设计与应用

通过研究现有无线矿山压力监测系统中液压支架传感器应用情况,发现普遍存在数据传输不稳定与传感器功耗高问题,为此利用无线Mesh自组网技术设计煤矿液压支架压力传感器,克服数据传输不稳定及功耗高的问题。以STM32L412单片机为核心处理器,定时采集液压支架压力数据,对压力数据进行处理和存储,并控制数据通过无线Mesh网络传输至监测分站,最终到达地面监测系统。设计中将无线Mesh模块唤醒机制与STM32L412单片机低功耗模式结合设计,保证数据传输可靠性同时,兼顾传感器低功耗。经过现场实际应用,所设计的液压支架压力传感器在矿井下环境中数据传输稳定、传感器功耗低,适合煤矿工作面液压支架压力采集监测。

基于蓝牙Mesh分布式控制和平均一致性的智慧照明系统

针对维持电力系统平衡向运行储备提出的更高要求,以及大型室内场所中LED照明负荷成为非旋转储备的问题,设计了一种基于蓝牙Mesh分布式控制和平均一致性算法的智慧照明系统。该照明系统采用蓝牙Mesh组网搭建的分布式网络,结合平均一致性算法,以较低的运算量控制大量灯具,在实现功率调整的同时确保用户舒适度趋于一致。实验结果表明:该系统中所有灯具能够在较短时间内完成目标功率容量的调节,同时减小了功率调节对用户舒适度造成的影响,有着网络资源消耗低、稳定性强、易扩展等优势,可以满足实际需求。

基于蜂窝结构的海上风电场无线Mesh网络覆盖优化算法

以往的海上风电场无线Mesh网络覆盖优化算法由于仅计算了单一的优化目标,导致算法的优化效果不佳。因此,设计了基于蜂窝结构的海上风电场无线Mesh网络覆盖优化算法。考虑到蜂窝结构的特性,得到基于蜂窝结构的海上风电场覆盖情况,根据覆盖区域中静态节点的分布情况,制定相应网络节点移动策略,在上述基础上,构建相应的风电场网络覆盖模型,并通过计算节点覆盖率和节点移动距离,得到相应的优化目标函数,通过计算移动节点的适应度,实现对风电场的网络覆盖优化。通过上述的设计,完成对海上风电场无线Mesh网络覆盖优化算法的设计。在实验测试中,和以往的海上风电场无线Mesh网络覆盖优化算法相比,设计的基于蜂窝结构的海上风电场无线Mesh网络覆盖优化算法在实际应用后,网络覆盖率提升到98.12%,优化效果较好。

基于BLE Mesh组网算法在冷库监测系统中的应用研究

高架立体冷库空间范围大、内部结构比较复杂,在使用传统无线组网技术对其进行温湿度监测时,通常存在组网方式复杂、功耗高的问题。以BLE Mesh组网方式为基础,通过构建节点能量模型,对传统LEACH算法进行针对性的优化,提出一种基于节点能量均衡的分簇组网算法(EBBM)。该算法主要对冷库温湿度监测网络中的节点功耗进行优化。Matlab仿真分析对比结果显示,该算法降低了网络中的数据包冗余程度,使节点存活率提高了17.8%,具有一定的应用价值。

基于Mesh网络的集群式照明管理系统设计

目前的mesh网络中若使用电池供电的传感器,则设备的频繁通信和控制会导致额外的能源消耗。因此,本文基于mesh网络设计了一款集群式照明管理的系统,通过对该系统总框架的设计,将系统所具备的功能分成了数据采集、网络拓扑结构、集群控制等三个模块。通过实验分析,验证出该系统在数据传输效率、控制精准度以及节能效果等方面均具有显著优势。

集群式照明管理中Mesh网络技术研究

面对网络拓扑动态变化、多跳传输带来的延迟问题,文章旨在深入探讨Mesh网络技术在集群式照明管理中的应用要点,以期进一步推动智能照明控制系统的实用化与智能化,为创造绿色、智能的城市生活提供有力的技术支撑。

Collaborative positioning for swarms:A brief survey of vision,LiDAR and wireless sensors based methods

As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from both its environment and other agents,an agent can use various methods and sensor types to localize itself.With its high flexibility and robustness,collaborative positioning has become a widely used method in both military and civilian applications.This paper introduces the basic fundamental concepts and applications of collaborative positioning,and reviews recent progress in the field based on camera,LiDAR(Light Detection and Ranging),wireless sensor,and their integration.The paper compares the current methods with respect to their sensor type,summarizes their main paradigms,and analyzes their evaluation experiments.Finally,the paper discusses the main challenges and open issues that require further research.

Progress of Proximity Sensors for Potential Applications in Electronic Skins

Recently,electronic skins and fl exible wearable devices have been developed for widespread applications in medical monitoring,artifi cial intelligence,human–machine interaction,and artifi cial prosthetics.Flexible proximity sensors can accurately perceive external objects without contact,introducing a new way to achieve an ultrasensitive perception of objects.This article reviews the progress of fl exible capacitive proximity sensors,fl exible triboelectric proximity sensors,and fl exible gate-enhanced proximity sensors,focusing on their applications in the electronic skin fi eld.Herein,their working mechanism,materials,preparation methods,and research progress are discussed in detail.Finally,we summarize the future challenges in developing fl exible proximity sensors.

一种小型无线Mesh监测终端中的功率放大器设计

为解决矿井下通用型无线Mesh监测终端中的射频收发前端尺寸过大的问题,提出一种矿井下小型无线Mesh监测终端的射频收发前端设计方案.对该射频收发前端的发射链路中的驱动功率放大器和末级功率放大器采用微带线与集总元件混合的匹配电路设计方式,大大减小了电路尺寸,研制的射频收发前端样机尺寸仅为98mm×72mm×17mm.测试结果表明,样机的发射性能达到设计指标,实现了射频收发前端的小型化;本文提出的混合匹配电路设计方法是有效的.

基于Q-Learning的动态BLE Mesh网络高能效路由算法

针对动态低功耗蓝牙(Bluetooth Low Energy, BLE)Mesh网络规范采用的管理式泛洪路由机制所导致的数据包冗余和高能耗的问题,提出了动态BLE Mesh网络高能效路由算法。通过建立基于Q-Learning的BLE Mesh网络路由模型,将BLE Mesh网络中节点的剩余能量、转发成本、移动因子以及接收信号强度指示(Received Signal Strength Indicator, RSSI)纳入到奖励函数的设计中。同时对BLE Mesh网络中的心跳机制进行改进,使网络中的节点更加高效地获取环境信息。采用基于探索的路由发现机制来更新网络中节点的Q值,使其能更加准确反映节点移动所导致的网络拓扑变化。仿真结果表明,该算法在节点能耗和网络开销上均优于传统的管理式泛洪路由机制。

Advances of Electrochemical and Electrochemiluminescent Sensors Based on Covalent Organic Frameworks

Covalent organic frameworks(COFs),a rapidly developing category of crystalline conjugated organic polymers,possess highly ordered structures,large specific surface areas,stable chemical properties,and tunable pore microenvironments.Since the first report of boroxine/boronate ester-linked COFs in 2005,COFs have rapidly gained popularity,showing important application prospects in various fields,such as sensing,catalysis,separation,and energy storage.Among them,COFs-based electrochemical(EC)sensors with upgraded analytical performance are arousing extensive interest.In this review,therefore,we summarize the basic properties and the general synthesis methods of COFs used in the field of electroanalytical chemistry,with special emphasis on their usages in the fabrication of chemical sensors,ions sensors,immunosensors,and aptasensors.Notably,the emerged COFs in the electrochemiluminescence(ECL)realm are thoroughly covered along with their preliminary applications.Additionally,final conclusions on state-of-the-art COFs are provided in terms of EC and ECL sensors,as well as challenges and prospects for extending and improving the research and applications of COFs in electroanalytical chemistry.

Recent progress on nanomaterial-based electrochemical dissolved oxygen sensors

Dissolved oxygen(DO)usually refers to the amount of oxygen dissolved in water.In the environment,medicine,and fermentation industries,the DO level needs to be accurate and capable of online monitoring to guide the precise control of water quality,clinical treatment,and microbial metabolism.Compared with other analytical methods,the electrochemical strategy is superior in its fast response,low cost,high sensitivity,and portable device.However,an electrochemical DO sensor faces a trade-off between sensitivity and long-term stability,which strongly limits its practical applications.To solve this problem,various advanced nanomaterials have been proposed to promote detection performance owing to their excellent electrocatalysis,conductivity,and chemical stability.Therefore,in this review,we focus on the recent progress of advanced nanomaterial-based electrochemical DO sensors.Through the comparison of the working principles on the main analysis techniques toward DO,the advantages of the electrochemical method are discussed.Emphasis is placed on recently developed nanomaterials that exhibit special characteristics,including nanostructures and preparation routes,to benefit DO determination.Specifically,we also introduce some interesting research on the configuration design of the electrode and device,which is rarely introduced.Then,the different requirements of the electrochemical DO sensors in different application fields are included to provide brief guidance on the selection of appropriate nanomaterials.Finally,the main challenges are evaluated to propose future development prospects and detection strategies for nanomaterial-based electrochemical sensors.

一种基于路由交叉优化的省内干线Mesh组网架构

为满足多传送节点之间业务的无阻塞交叉调度,传统的省内干线光传送网受限于设备交叉能力和调度能力,亟需逐步向Mesh化演进。提出一种基于路由交叉优化的省内干线Mesh组网架构,将现有省内干线光缆交叉处转变为光交叉连接中间节点,并根据实际组网光缆路由,给出多种应用场景,提出相关的Mesh化演进策略。

Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.