Electronic,Thermal Expanding,and Optical Absorption Properties of Transition Metal Dichalcogenides: A First-principles Study

A comprehensive investigation was made on the electronic structure, thermal expansion coefficient and light absorption spectrum of total six transition metal dichalcogenides (TMDs) compounds with formula of MX₂ (M=Mo, W, Cr, X=S, Se). First, an indirect-direct band gap transition from bulk to singlelayer was declared for all the six compounds. Moreover, the detailed lattice constants and thermal expansion coefficients provided in the paper were the key information for designing MX₂-based field effect transistors. Finally, the calculated optical absorption spectra demonstrate that these compounds can effectively utilize solar energy and are good photo catalyst candidates. All these present findings will benefit the design of new generation of novel two-dimensional materials.     

图像识别技术在变电站安全布防的研究

目前换流站、变电站的安全布防措施还没有采用图像分析技术的报道,对于主动安全监管存在如下隐患:①当有作业人员发生超越施工范围工作时,无现场声光报警警示功能提醒,从而无法及时阻止现场违章人员的违章行为;②常规的安全隔离措施不具备远端监控中心安全预警及现场视频联动功能,特别是违章发生后无现场视频记录,对违章处罚,特别是事故调查也带来极大不便;③无法实时监视、提醒使用施工车辆或工器具在带电设备下方进行做业检修施工人员其自身或是工器具高度已超过安全警戒值;④安全标示牌无法做到四周完全覆盖,造成工作人员未见标志而误入,存在安全隐患;⑤由于现场摄像机布置数量较少,并不能对每个间隔都做到完整无死角监控,故远端监控中心不能对检修进行全域的安全监控.     

PCS600系统在商业综合体中的应用

本文主要介绍了PCS600系统在新城控股集团吾悦广场商业综合体项目中的典型应用,通过对商场内各机电设备数据的采集,实现“分布式、一体化”的控制效果,利用客户端对商场内所有机电设备进行实时监控,分析数据并对各种预警进行快速处理。