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931.
作为电力系统未来发展的方向,对电网设备故障监控系统进行设计具有重要意义.有利于实现电网进行安全可靠运行.提出基于ZigBee网络的电网设备故障高精度远程视频监控系统设计.利用ZigBee网络构建无线的传感网,节点是采用的CC2530,节点间采用簇状的结构与监控功能部分、视频监控信号传输以及监控的客户端相结合构成远程视频的监控系统,采用小波变换对设备故障的特征进行分析,克服了因雾霾天气产生的电网设备故障,对电网设备故障进行及时的抢修,完成对电网设备故障高精度远程视频监控系统的设计.实验结果表明,利用该系统能有效地提高电网运行的稳定性与安全性. 相似文献
932.
浙江北部一次爆发式发展重度大气污染的气象特点和成因 总被引:1,自引:0,他引:1
基于全国空气质量指数和PM_(2.5)监测、常规气象观测、浙江省6种主要大气污染物和自动气象监测、宁波镇海激光雷达、美国国家环境预报中心GDAS和欧洲中期天气预报中心ERA-interim再分析等多种资料,对2017年12月30日―2018年1月1日浙江北部一次爆发式发展大气污染事件气象特点及成因进行分析,应用HYSPLIT4模式进行粒子后向轨迹分析.结果表明:PM_(10)和PM_(2.5)质量浓度在浙江省表现出明显的爆发性增长和自西北向东南传输的特征,污染程度自浙北向浙中、浙南逐渐减轻,重度污染时浙北大范围出现2000 m以下的重度霾,污染粒子主要来自上游的安徽和江苏省.大气污染爆发式发展与冷空气有关,1000 m以下边界层内冷空气偏弱,但足以将盛行风改变为西北风,是污染物粒子输送的动力条件,污染粒子集中在该层内,层内没有下沉运动,因此水平风场对污染事件爆发有决定性作用;1000 m以上层次冷平流表现明显,且伴有下沉运动,抑制了边界层粒子的垂直扩散,对污染事件的发展和维持有间接影响.激光雷达的消光系数变化不仅与污染物粒子浓度变化有关,还与气象条件密切相关.污染物粒子质量浓度通量散度的变化对预报粒子浓度的增减有较好的参考作用. 相似文献
933.
2011~2012北京大气PM2.5中重金属的污染特征与来源分析 总被引:14,自引:12,他引:2
为研究北京PM_(2.5)中重金属污染特征,于2011年夏季~2012年夏季每3 d采集一次PM_(2.5)样品.利用电感耦合等离子体质谱(ICP-MS)分析了Li、V、Cr、Mn、Co、Cu、Zn、As、Se、Ti、Ga、Ni、Sr、Cd、In、Ba、Tl、Pb、Bi和U的浓度,选取其中Zn、Pb、Mn、Cu、As、V和Cr 7种主要重金属元素进行深入讨论.北京市PM_(2.5)中重金属Zn、Pb、Mn、Cu、As、V和Cr的平均质量浓度分别为(331.30±254.52)、(212.64±182.06)、(85.96±47.00)、(45.19±27.74)、(17.13±19.02)、(4.92±3.38)和(9.04±7.84)ng·m-3.采样期间秋冬季节PM_(2.5)中重金属污染较春夏季节严重,这可能与北京秋冬季节取暖导致煤燃烧增加有关.霾过程会加剧北京PM_(2.5)中主要重金属Zn、Pb、Mn、Cu、As、V和Cr的污染,霾天对重金属污染的增加作用呈现一定的季节变化特征.源分析结果表明北京大气颗粒物中重金属主要来源于扬尘(包括建筑扬尘和道路扬尘)和煤燃烧,少量来自远距离输送和其他工业来源. 相似文献
934.
This paper analyses structural and personal exposure to Hurricane Katrina. Structural exposure is measured by flood height and building damage; personal exposure is measured by the locations of 911 calls made during the response. Using these variables, this paper characterises the geography of exposure and also demonstrates the utility of a robust analytical approach in understanding health‐related challenges to disadvantaged populations during recovery. Analysis is conducted using a contemporary statistical approach, a multiple additive regression tree (MART), which displays considerable improvement over traditional regression analysis. By using MART, the percentage of improvement in R‐squares over standard multiple linear regression ranges from about 62 to more than 100 per cent. The most revealing finding is the modelled verification that African Americans experienced disproportionate exposure in both structural and personal contexts. Given the impact of exposure to health outcomes, this finding has implications for understanding the long‐term health challenges facing this population. 相似文献
935.
Sugimoto JD Labrique AB Ahmad S Rashid M Shamim AA Ullah B Klemm RD Christian P West KP 《Disasters》2011,35(2):329-345
The epidemiology of tornado-related disasters in the developing world is poorly understood. An August 2005 post-tornado cohort study in rural Bangladesh identified elevated levels of death and injury among the elderly (≥ 60 years of age) (adjusted odds ratio (AOR) = 8.9 (95 per cent confidence interval (CI): 3.9-20.2) and AOR = 1.6 (95 per cent CI: 1.4-1.8), respectively), as compared to 15-24 year-olds, and among those outdoors versus indoors during the tornado (AOR = 10.4 (95 per cent CI: 5.5-19.9) and AOR = 6.6 (95 per cent CI: 5.8-7.5), respectively). Females were 1.24 times (95 per cent CI: 1.15-1.33) more likely to be injured than males. Elevated risk of injury was significantly associated with structural damage to the house and tin construction materials. Seeking treatment was protective against death among the injured, odds ratio = 0.08 (95 per cent CI: 0.03-0.21). Further research is needed to develop injury prevention strategies and to address disparities in risk between age groups and between men and women. 相似文献
936.
The 2008 Disaster Mitigation Preparedness (DMP) study took place in Aceh province, Indonesia. It sought to help develop radio programmes and messages to increase resilience to disasters. The role of radio was evaluated during and after the 2004 Asian tsunami disaster. The study team interviewed 984 tsunami survivors from nine sub-districts of Banda Aceh, and local nongovernmental organisations convened eight focus groups around the area of Aceh Besar. Six key informant interviews were held with government disaster management agencies. The DMP survey is the first of its kind to interview a representative random sample of Banda Aceh residents. It reveals the importance of community and social networks, during disaster situations, when essential communications are down. A disaster warning information system based on a multi-media approach needs to be developed. The wider community should be involved in the planning, education and training of Banda Aceh and Aceh Besar residents to facilitate appropriate personal and community survival strategies. 相似文献
937.
分析了应对重大灾害的应急物资需求的特点和我国现有应急物资储备体系的现状和不足,基于轴辐网络优势,构建了轴辐式应急物资储备网络体系,分析了应急轴辐网络储备体系运行的四个阶段,同时提出了建立轴辐式应急物资储备网络相关具体措施建议,实现中央和地方应急储备库物资、各职能部门储备物资、军队物资、各社会团体储备物资、国内外捐助物资以及企业物资生产能力储备等专业应急物资储备和社会应急物资储备的有效整合,以有助于在较短时间内积聚大量应急物资,扩大应急物资的服务辐射范围,提高应急物资调度效率,以有效应对各类重大灾害。 相似文献
938.
939.
张兵 《中国安全生产科学技术》2013,(10):157-161
分析总结了“6·3”吉林省长春市德惠市吉林宝源丰禽业有限公司主厂房特别重大火灾爆炸事故发生、蔓延、扩大及造成重大人员伤亡的主要原因,吸取其在消防设计、施工、验收中存在的经验教训。针对目前现行消防技术标准并结合工作实际,从火灾自动报警系统的设置、火灾探测器的选型、自动喷水灭火系统喷头的设置、建筑隔墙的设计施工、提高(保温)隔热材料的防火性能及施工等方面探讨了完善优化冷库建筑消防安全防火设计的措施,为有关消防技术标准规范的修订提供了参考。 相似文献
940.
Patterns of preference and practice: bridging actors in wildfire response networks in the American Northwest 下载免费PDF全文
A.J. Faas Anne‐Lise K. Velez Clare FitzGerald Branda L. Nowell Toddi A. Steelman 《Disasters》2017,41(3):527-548
The roles of bridging actors in emergency response networks can be important to disaster response outcomes. This paper is based on an evaluation of wildfire preparedness and response networks in 21 large‐scale wildfire events in the wildland—urban interface near national forests in the American Northwest. The study investigated how key individuals in responder networks anticipated seeking out specific people in perceived bridging roles prior to the occurrence of wildfires, and then captured who in fact assumed these roles during actual large‐scale events. It examines two plausible, but contradictory, bodies of theory—similarity and dissimilarity—that suggest who people might seek out as bridgers and who they would really go to during a disaster. Roughly one‐half of all pre‐fire nominations were consistent with similarity. Yet, while similarity is a reliable indicator of how people expect to organise, it does not hold up for how they organise during the real incident. 相似文献