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。

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。

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.

面向算力网络的全光网MESH化组网规划研究

全光承载网络是算力网络的根基和底座,面向算力网络的业务发展需求将呈现MESH化组网的趋势。在分析算力网络对光网络需求的基础上,对比了全光网MESH化组网和传统组网的差异,进而研究全光网络MESH化组网规划思路与规划重点,最后提出了全光网MESH化部署相关建议,以期更好地助力算力网络新发展。

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。

Determination of Veterinary Drug Residues in Animal-derived Foods by Liquid Chromatography-Mass Spectrometry

[Objectives]This study was conducted to establish a rapid and effective method for simultaneous extraction of 54 kinds of veterinary drug residues in animal-derived food, including sulfonamides, quinolones, tetracyclines, malachite greens, penicillins, nitroimidazoles, tranquilizers and macrolides, by HPLC-MS. [Methods] The samples were extracted with 80% acetonitrile water(containing 0.1% formic acid), combined with QuEChERS extraction technology and C18 and PSA purification, analyzed by high performance liquid chromatography-mass spectrometry, and quantified by external standard method. The target substances were analyzed on ZORBAX Eclipse C18 chromatographic column using 0.2% formic acid water and 0.2% methanol as mobile phases. The gradient elution mode was used for chromatographic separation and multiple reaction detection. [Results] In the linear range of 0.5-50.0 ng/ml, the linear relationship of the 54 kinds of veterinary drug residues was good, with correlation coefficients(r~2) greater than 0.995, and the detection limits ranged from 0.30 to 1.00 μg/kg. The results showed that the recovery ranged from 75.4% to 118.2% when different matrixes were added for recovery. [Conclusions] This method is simple, efficient, accurate, stable, and highly operable. It is applicable to simultaneous batch screening of veterinary drug residues in animal-derived food, and has high practical application value.

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。

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。

An Alternative Method for Incorporating Fiber Meshes in Complete Upper Dentures

The most commonly used material for constructing complete dentures is polymethyl methacrylate (PMMA). However, the strength characteristics of PMMA, such as impact strength and fatigue strength, are poor, and fracturing of PMMA dentures is a common problem in prosthodontic practice. Reinforcing PMMA with various materials, such as carbon fibers, glass fibers (fiberglass), and ultrahigh modulus polyethylene fibers, has been suggested to strengthen the denture-base material. A common problem encountered when packing the resin on these specimens is fiber slippage beyond the denture edges. The present study proposes an alternative method of incorporating fiber meshes into complete dentures, whereby a thin filament of self-polymerizing resin at the perimeter of the fiber mesh is produced, giving a clear and stable shape to the mesh that fits the upper jaw cast. During placement of the shaped mesh on the cast, a positive-negative relationship is created between the mesh and cast, which immobilizes the mesh during the incorporation process.

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。

Flexible, Transparent and Conductive Metal Mesh Films with Ultra‑High FoM for Stretchable Heating and Electromagnetic Interference Shielding

Despite the growing demand for transparent conductive films in smart and wearable electronics for electromagnetic interference(EMI)shielding,achieving a flexible EMI shielding film,while maintaining a high transmittance remains a significant challenge.Herein,a flexible,transparent,and conductive copper(Cu)metal mesh film for EMI shielding is fabricated by self-forming crackle template method and electroplating technique.The Cu mesh film shows an ultra-low sheet resistance(0.18Ω□^(-1)),high transmittance(85.8%@550 nm),and ultra-high figure of merit(>13,000).It also has satisfactory stretchability and mechanical stability,with a resistance increases of only 1.3%after 1,000 bending cycles.As a stretchable heater(ε>30%),the saturation temperature of the film can reach over 110°C within 60 s at 1.00 V applied voltage.Moreover,the metal mesh film exhibits outstanding average EMI shielding effectiveness of 40.4 dB in the X-band at the thickness of 2.5μm.As a demonstration,it is used as a transparent window for shielding the wireless communication electromagnetic waves.Therefore,the flexible and transparent conductive Cu mesh film proposed in this work provides a promising candidate for the next-generation EMI shielding applications.

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。

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。

Four-Order Superconvergent Weak Galerkin Methods for the Biharmonic Equation on Triangular Meshes

A stabilizer-free weak Galerkin(SFWG)finite element method was introduced and analyzed in Ye and Zhang(SIAM J.Numer.Anal.58:2572–2588,2020)for the biharmonic equation,which has an ultra simple finite element formulation.This work is a continuation of our investigation of the SFWG method for the biharmonic equation.The new SFWG method is highly accurate with a convergence rate of four orders higher than the optimal order of convergence in both the energy norm and the L^(2)norm on triangular grids.This new method also keeps the formulation that is symmetric,positive definite,and stabilizer-free.Four-order superconvergence error estimates are proved for the corresponding SFWG finite element solutions in a discrete H^(2)norm.Superconvergence of four orders in the L^(2)norm is also derived for k≥3,where k is the degree of the approximation polynomial.The postprocessing is proved to lift a P_(k)SFWG solution to a P_(k+4)solution elementwise which converges at the optimal order.Numerical examples are tested to verify the theor ies.

High Order Finite Difference WENO Methods for Shallow Water Equations on Curvilinear Meshes

A high order finite difference numerical scheme is developed for the shallow water equations on curvilinear meshes based on an alternative flux formulation of the weighted essentially non-oscillatory(WENO)scheme.The exact C-property is investigated,and comparison with the standard finite difference WENO scheme is made.Theoretical derivation and numerical results show that the proposed finite difference WENO scheme can maintain the exact C-property on both stationarily and dynamically generalized coordinate systems.The Harten-Lax-van Leer type flux is developed on general curvilinear meshes in two dimensions and verified on a number of benchmark problems,indicating smaller errors compared with the Lax-Friedrichs solver.In addition,we propose a positivity-preserving limiter on stationary meshes such that the scheme can preserve the non-negativity of the water height without loss of mass conservation.

基于5G技术的消防Mesh专网基站设计

设计了一款基于5G技术的消防Mesh专网通信基站,基于双向OFDM传输技术、载波聚合、无线感知抗干扰、混合场景下路由算法等关键技术,在不提高基站发射功率的前提下,增大网络通信速率,扩大传输距离,提高抗干扰性能,并进行了实验室环境下网络性能测试和外场应用测试。试验结果表明,专网基站最大通信带宽可达100 Mbps,基站点对点传输距离可达80 km以上,可有效避免同频段其他无用信号的干扰,多跳组网后仍具备较高的数据传输能力且时延与双跳组网基本一致,该基站可以作为数字化战场的核心通信节点,解决传统Mesh设备和技术面临的难题。

Determination method of mesh size for numerical simulation of blast load in near-ground detonation

In order to improve the overall resilience of the urban infrastructures, it is required to conduct blast resistant design for important building structures in the city. For complex terrain in the city, it is recommended to determine the blast load on the structures via numerical simulation. Since the mesh size of the numerical model highly depends on the explosion scenario, there is no generally applicable approach for the mesh size selection. An efficient method to determine the mesh size of the numerical model of near-ground detonation based on explosion scenarios is proposed in this study. The effect of mesh size on the propagation of blast wave under different explosive weights was studied, and the correlations between the mesh size effect and the charge weight or the scaled distance was described. Based on the principle of the finite element method and Hopkinson-Cranz scaling law, a mesh size measurement unit related to the explosive weight was proposed as the criterion for determining the mesh size in the numerical simulation. Finally, the applicability of the method proposed in this paper was verified by comparing the results from numerical simulation and the explosion tests and was verified in AUTODYN.

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.