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101.
高速公路交通救援资源派遣方法适用性研究 总被引:1,自引:0,他引:1
为降低高速公路交通事故人员伤亡和财产损失、提高指挥调度中心救援效率,将适合高速公路交通救援资源派遣的匈牙利法、直接成本法和机会成本法,分别从基于资源派遣方法的数学特征、高速公路交通救援点配置情况和交通事故救援实施3个方面对各方法的适用性进行研究,并结合指挥调度中心现有资源派遣实际,制定出交通救援资源派遣规则。以南京市周边高速公路网为例,根据适用条件选用合适的交通救援资源派遣方法和派遣规则,进行救援资源的派遣决策,为指挥调度中心高效地派遣交通救援资源提供了理论依据和合适方法。 相似文献
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HydroShare: Sharing Diverse Environmental Data Types and Models as Social Objects with Application to the Hydrology Domain 下载免费PDF全文
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政府环境报告基层实施是利用县级人大与公众直接联系的"基层"优势加强对政府环境责任监督的有效手段。实践中,报告主体及对象级别各异,报告内容繁简不一,总体情况为越是基层贯彻实施政府环境报告的力度越弱,存在报告形式不明确、信息公开不到位、常态化监督机制和政府责任缺失等问题。因此,必须在认清立法目的的基础上合理运用法律解释明确报告的法律属性,规范报告内容、扩大公开范围,利用"基层"优势与公众加强联系,并在准确定位环保法的前提下构建人大监督的刚性约束。 相似文献
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Distribution of heavy metals in agricultural soils near a petrochemical complex in Guangzhou, China 总被引:2,自引:0,他引:2
Li J Lu Y Yin W Gan H Zhang C Deng X Lian J 《Environmental monitoring and assessment》2009,153(1-4):365-375
The aim of the study was to investigate influence of an industrialized environment on the accumulation of heavy metals in agricultural soils. Seventy soil samples collected from surface layers (0-20 cm) and horizons of five selected pedons in the vicinity area of petrochemical complex in Guangzhou, China were analyzed for Zn, Cu, Pb, Cd, Hg and As concentrations, the horizontal and vertical variation of these metals were studied and geographic information system (GIS)-based mapping techniques were applied to generate spatial distribution maps. The mean concentrations of these heavy metals in the topsoils did not exceed the maximum allowable concentrations in agricultural soil of China with the exception of Hg. Significant differences between land-use types showed that Cu, Pb, Cd, Hg and As concentrations in topsoils were strongly influenced by agricultural practices and soil management. Within a radius of 1,300 m there were no marked decreasing trends for these element concentrations (except for Zn) with the increase of distance from the complex boundary, which reflected little influence of petroleum air emission on soil heavy metal accumulation. Concentrations of Zn, Cu, Pb, Cd, Hg and As in the five pedons, particularly in cultivated vegetable field and orchard, decreased with soil depth, indicating these elements mainly originated from anthropogenic sources. GIS mapping was a useful tool for evaluating spatial variability of heavy metals in the affected soil. The spatial distribution maps allowed the identification of hot-spot areas with high metal concentration. Effective measures should be taken to avoid or minimize heavy metal further contamination of soils and to remediate the contaminated areas in order to prevent pollutants affecting human health through agricultural products. 相似文献
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Passive air monitoring of PCBs and PCNs across East Asia: a comprehensive congener evaluation for source characterization 总被引:1,自引:0,他引:1
Hogarh JN Seike N Kobara Y Habib A Nam JJ Lee JS Li Q Liu X Li J Zhang G Masunaga S 《Chemosphere》2012,86(7):718-726
A comprehensive congener specific evaluation of polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) in the atmosphere was conducted across East Asia in spring 2008, applying polyurethane foam (PUF) disk passive air sampler (PAS) as monitoring device. Mean concentrations derived for Japan, China and Korea were 184 ± 24, 1100 ± 118, and 156 ± 20 pg m−3 for ∑202 PCBs, and 9.5 ± 1.5, 61 ± 6, and 16 ± 2.4 pg m−3 for ∑63 PCNs, respectively. Relative to reported data from 2004, the present results suggest that air PCBs concentrations have not changed much in Japan and Korea, while it has increased by one order of magnitude in China. From principal component analysis, combustion emerged highly culpable in contemporary emissions of both PCBs and PCNs across the East Asian sub-region. Another factor derived as important to air PCBs was re-emissions/volatilization. Signals from PCBs formulations were also picked, but their general importance was virtually consigned to the re-emissions/volatilization tendencies. On the contrary, counterpart PCNs formulations did not appear to contribute much to air PCNs. 相似文献
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