Development of diabetic complications and influencing factors among 32653 type 2 diabetes patients:retrospective cohort study using a multi-state Markov

Background:Patients with type 2 diabetes are at high risk for developing multiple chronic complications.However,there is a lack of studies of the cumulative number of diabetic complications in China.Methods:A retrospective cohort study was performed from 2009 to 2021.Type 2 diabetes patients who were first diagnosed after the age of 35 years between January 1,2009,and December 31,2017,were included.Five states were defined according to the number of chronic complications:no(S0),one(S1),two(S2),three(S3),and four or more complications(S4).A multi-state Markov model was constructed to estimate transition probability,transition intensity,mean sojourn time,and the possible factors for each state.Results:The study included 32653 type 2 diabetes patients(mean age,59.59 years;15929(48.8%)male),and mean follow-up time of 7.75 years.In all,4375 transitions were observed.The 12-year transition probability of from state S0 to S1 was the lowest at 16.4%,while that from S2 to S3 was the highest,at 45.6%.Higher fasting blood glucose,lower high-density lipoprotein cholesterol,higher total cholesterol,and an unhealthy diet were associated with higher risk of progression from S0 to S1.Being female,less than 60 years old,weekly physical activity,and vegetarian diet decreased this risk.Being female and less than 60 years old reduced the likelihood of transition from S1 to S2,whereas lower high-density lipoprotein cholesterol increased this likelihood.Conclusions:Following the occurrence of two complications in type 2 diabetes patients,the risk for accumulating a third complication within a short time is significantly increased.It is important to take advantage of the stable window period when patients have fewer than two complications,strengthen the monitoring of blood glucose and blood lipids,and encourage patients to maintain good living habits to prevent further deterioration.

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.

矿用无线Mesh自组网基站设计

针对矿难事故发生后井下通信系统瘫痪、井下救援人员无法与前方指挥部及时沟通和进行音视频信息交互的问题,设计了一种矿用无线Mesh自组网基站。该基站采用无线Mesh自组网通信技术,以FPGA+ARM为控制芯片、AD9361为射频芯片,采用ARM处理系统模块、可编程逻辑模块、射频模块、AXI总线模块搭建硬件平台,最后对电源模块进行本质安全设计。测试结果表明,该基站满足井下的应急通信要求。

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。

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。

A Two-Step Algorithm to Estimate Variable Importance for Multi-State Data:An Application to COVID-19

Survival data with amulti-state structure are frequently observed in follow-up studies.An analytic approach based on a multi-state model(MSM)should be used in longitudinal health studies in which a patient experiences a sequence of clinical progression events.One main objective in the MSM framework is variable selection,where attempts are made to identify the risk factors associated with the transition hazard rates or probabilities of disease progression.The usual variable selection methods,including stepwise and penalized methods,do not provide information about the importance of variables.In this context,we present a two-step algorithm to evaluate the importance of variables formulti-state data.Three differentmachine learning approaches(randomforest,gradient boosting,and neural network)as themost widely usedmethods are considered to estimate the variable importance in order to identify the factors affecting disease progression and rank these factors according to their importance.The performance of our proposed methods is validated by simulation and applied to the COVID-19 data set.The results revealed that the proposed two-stage method has promising performance for estimating variable importance.

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。

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。

基于无线Mesh网络的物联智能信息化病房系统设计

利用Mesh无线网络技术构建院内物联网平台,不仅实现了患者病情的精准监测与个体化住院环境的定制,还通过整合和智能分析生命体征等实时监测数据,有效辅助了临床诊疗和护理工作,极大地提升了医疗服务的质量和效率。通过部署在医院各个角落的Mesh节点,确保了网络的稳定性和覆盖范围,使得患者无论在病房还是公共区域,其健康数据都能实时上传至中央系统。医疗团队可以通过平台获取实时数据,进行远程监控和及时干预,减少了医疗事故的发生。同时,系统也高度重视数据安全和隐私保护,采用先进的加密技术和访问控制机制,确保患者信息得到严密保护,防止未经授权的访问和数据泄露,从而构建了一个高效、安全、智能的医疗物联网生态系统,全面提升了医院的管理水平和患者的就医体验。

Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial measurement.We propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine tools.This method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement method.We consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic chain.The four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization iteration.The experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser tracer.For a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed algorithm.This research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

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.