Results 1 to 10 of about 2,695 (156)

Research on Lightning Performance and Protective Measures of ±800 kV UHVDC Power Transmission Line [PDF]

open access: yes, 2023
[Introduction] Lightning strike is the primary cause of failures of ±800 kV UHVDC power transmission lines, and the lightning protection assessment of power transmission lines is critical to the safe and stable operation of the system.
Youjun GONG, Zhiwen HE, Ziwei YAN
core   +1 more source

Research on lightning transient distribution characteristics of cable-stayed bridges [PDF]

open access: yes, 2023
Bridges are usually located at the junction of land and water, where the surrounding area is open terrain, making them to be easily damaged by lightning strikes.
Dajun XU   +4 more
core   +1 more source

Highly Efficient Biotransformation of Astragaloside IV to Cycloastragenol by Sugar-Stimulated ¥ é-Glucosidase and é é-Xylosidase from Dictyoglomus thermophilum

open access: yesJournal of Microbiology and Biotechnology, 2019
β-Glucosidases and β-xylosidases are two categories of enzymes that could cleave out nonreducing, terminal β-D-glucosyl and β-D-xylosyl residues with release of D-glucose and Dxylose, respectively. In this paper, two functional β-glucosidase Dth3 and β-xylosidase Xln-DT from Dictyoglomus thermophilum were heterologously expressed in E.coli BL21 (DE3 ...
Qi, Li   +5 more
openaire   +3 more sources

Current status and developing recommendations of tailings dam failure [PDF]

open access: yes, 2018
This is the final version of the article. Available from Hindawi Publishing Corporation via the DOI in this record.Tailings dam failure accidents with limited emergency response time and huge potential threats, can often lead to heavy casualties and ...
Bu, L   +4 more
core   +1 more source

Analysis of characteristics of lightning disaster and risk zoning in Ningbo Area(宁波地区雷电灾害特征分析及风险区划)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2014
根据宁波地区ADTD闪电定位系统2010~2012年的地闪监测数据、雷灾资料以及2012年宁波地区人口及GDP数据,选取年平均地闪密度、单位面积雷灾频数、经济损失、人员伤亡、人员易损、经济易损6项指标,在详细分析宁波雷灾分布特征的基础上,采用主成分分析法对宁波各县地区雷灾易损性指标进行综合评价,并利用分层聚类分析法得出:政治经济文化中心的海曙区为雷灾极高易损区,经济发达的江东区以及工业基地镇海区为高易损区,江北区为中易损区,鄞州区、北仑区、象山县、宁海县、奉化市为低易损区,慈溪市和余姚市为极低易损区.
SHIXiangbo(石湘波)   +3 more
doaj   +1 more source

基于单片机的LED智能照明系统 [PDF]

open access: yes, 2017
本文在总结了前人LED的基础上,利用单片机智能控制的方法研究智能LED的设计和制备,利用色度学三基色配色原理,通过更改三基色LED的电流大小实现整体LED系统的调光和调色,系统可实现亮度20%-100%的调节,实现全彩调节,满足人们的多样化照明需求;同时可通过手机APP利用红外技术实现LED的无线遥控 ...
曹文越
core   +1 more source

风电机组非金属机舱的雷击附着特性数值仿真与防护设计

open access: yesDianci bileiqi, 2022
风电机组的雷电防护是风机安全稳定运行的基本条件,目前国内外对于风电机组的雷电防护主要集中在叶片的防雷研究,对机舱的防雷保护研究较少,而现有的接闪装置无法完全保护机舱。本研究建立含金属桁架与气象站避雷针的机舱模型,通过有限元仿真软件对雷击机舱尾部附着区域进行仿真,进而分析增设不同接闪装置的雷击防护效率,以及改进金属桁架结构对雷击防护效率的影响。研究表明:气象站避雷针无法完全保护机舱;增设的避雷针雷击防护效率高于饼状接闪器,且长度为20 cm的避雷针防护效率最佳;将金属桁架的结构改进后 ...
周歧斌, 王玺, 史一泽, 边晓燕
doaj  

边坡稳定性监测系统防雷设计及应用

open access: yesDianci bileiqi, 2020
针对边坡稳定性监测系统复杂工况条件下的设备防雷问题,分析直击雷和感应雷两种引起设备损坏的雷电危害和其危害方式。根据不同种类雷电危害的特点及监测设备的防护需求,设计采用由多针型避雷针、信号线屏蔽套管、防雷器、多级电源开关和人工接地网等装置构成的外部防雷措施和内部防雷措施结合的综合防雷系统,为边坡稳定性监测设备提供防雷保护,保证设备安全平稳运行。
李建宇   +4 more
doaj  

E o palhaço o que é? É uma mulher

open access: yesArteriais - Revista do Programa de Pós-Gradução em Artes, 2019
ResumoEste ensaio traz a fala de uma mulher que descobre em si um palhaço, mesmo atuando, há 13 anos, como palhaça. O encontro com o palhaço Uisquisito ocorreu em 2012, no grupo de teatro Palhaços Trovadores, do qual faço parte há 10 anos. A partir disso, atuar na palhaçaria com gêneros diferentes, feminino e masculino, trouxe-me reflexões não só na ...
openaire   +3 more sources

三峡近区500 kV出线雷电综合治理效果分析

open access: yesDianci bileiqi, 2020
雷害是架空输电线路跳闸的首要原因,为降低线路雷击跳闸率,提升线路雷电防护水平,运行单位需对输电线路进行雷害风险评估,并针对高雷害风险等级杆塔采取差异化的防雷措施。目前针对防雷措施治理效果分析方法主要通过对比改造前后线路雷击跳闸次数或雷击跳闸率的变化,该方法简单直观,但由于一条线路往往采取多种防雷措施,以及改造前后雷电活动的差异性等造成综合防雷效果的评价实施非常困难。通过分析三峡近区2000-2018年雷电活动情况、跟踪15条500 k V出线防雷措施的滚动实施情况及其历年的雷击运行数据 ...
马建国   +6 more
doaj  

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