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901.
ABSTRACT: The Kirkwood‐Cohansey aquifer has been identified as a critical source for meeting existing and expected water supply needs for southern New Jersey. Several contaminated sites exist in the region; their impact on the aquifer has to be evaluated using ground water flow and transport models. Ground water modeling depends on availability of measured hydrogeologic data (e.g., hydraulic conductivity, for parameterization of the modeling runs). However, field measurements of such critical data have inadequate spatial density, and their locations are often clustered. The goal of this study was to research, compile, and geocode existing data, then use geostatistics and advanced mapping methods to develop a map of horizontal hydraulic conductivity for the Kirkwood‐Cohansey aquifer. Spatial interpolation of horizontal hydraulic conductivity measurements was performed using the Bayesian Maximum Entropy (BME) Method implemented in the BMELib code library. This involved the integration of actual measurements with soft information on likely ranges of hydraulic conductivity at a given location to obtain estimate maps. The estimation error variance maps provide an insight into the uncertainty associated with the estimates, and indicate areas where more information on hydraulic conductivity is required.  相似文献   
902.
超声回弹综合法测强曲面五参数幂函数公式   总被引:6,自引:0,他引:6  
提出了一种新的混凝土 f -v -R曲面五参数幂函数公式 ,它能够很好地描述混凝土的超声值v、回弹值Rm 和抗压强度值 f之间的关系 ,克服了传统的 f -v -R曲面公式拟合试验数据误差较大的缺点 ,在实际工作中 ,采用这种新提出的 f -v -R曲面公式 ,可以更准确地评价建筑结构的混凝土强度  相似文献   
903.
联邦德国自然灾害保险述评   总被引:2,自引:0,他引:2  
灾害保险作为减轻灾害损失的重要手段,受到了国际社会的广泛关注。本文评述了德国的自然灾害保险发展体系及保险人、保险业及国家在灾害保险中的职能关系,可为我国开展灾害保险提供借鉴。  相似文献   
904.
The Bakken shale play in western North Dakota is one of the largest unconventional oilfields in the United States, but published research about impacts on the region's water resources is rare. In this study, besides examining North Dakota water management policies and activities, we also analyzed three datasets: the Bakken horizontal well completion data (2008‐2014), North Dakota permitted water consumption data (2000‐2014), and groundwater level and streamflow observations in western North Dakota (2000‐2014). We found from 2008 to 2014, the annual total industrial water uses for Bakken shale oil development ranged between 0.5 and 10% of statewide total consumptive water use. The percentage increases were between 3.0 and 40% within the Bakken oil production region. The increased population of temporary oilfield service workers contributed additional domestic water use, which was equivalent to ~15% of annual industrial water use for the shale oil development in the Bakken. Despite being in a semiarid region, the impact of Bakken development on regional water supply was limited because the water in the Bakken was adaptively managed and the region received on average over 20% more precipitation than normal during 2008‐2014. Of the 15 glaciofluvial aquifers under study, 12 have seen water levels increasing or unchanged and the water levels for the remaining 3 aquifers have decreased.  相似文献   
905.
俞峥嵘  张彤  罗建宇  郑鸣  孙莉 《安全》2021,42(8):20-24
为提高公交行车安全,本文以杭州公交为例对行车安全进行危险源辨识和风险分析,确立静态风险评价指标(占0.4)及动态风险评价指标(占0.6),按照风险等级划分标准,确立企业风险管控分级.基于基础风险数据,提出公交运营风险研判与预警信息系统的构建方案,实现风险的及时预警及精准管控,为管理者做出决策提供科学服务,从而有效遏制重特大事故发生.  相似文献   
906.
本文通过用"感官6级分类法"和"三点比较式嗅袋法"两种感官测试方法对三家制药厂恶臭污染进行对比分析,研究经济发展过程中产生的和人民群众日益重视的恶臭污染问题。  相似文献   
907.
黄浦江上游水源保护区水质评价与分析   总被引:2,自引:0,他引:2  
黄浦江上游保护区是上海环境保护工作的重点,其水质状况直接影响上海的饮水安全,分析影响该区域水质的主要水质因子。研究水质的分布特点和近年(2000年-2004年)的发展变化趋势,本文使用因子分析法通过对2000年-2004年黄浦江上游水源保护区的常设监测断面水质进行了分析,得出了黄浦江上游水质保护区的特征污染因子,再使用幂指数法、加权平均法、向量模法等水质综合评价方法对该区域的水质进行了评价,并得到了该区域的水质分布特点。  相似文献   
908.
Many studies have indicated that ozone is associated with morbidity and mortality. A few studies have reported that the association is heterogeneous across seasons and geographic regions. However, little information is available on whether both temperature and geographic factors simultaneously modify the ozone effect. This study used a Poisson regression model to explore whether temperature modifies the effect of ozone on mortality in the 60 large eastern US communities during April to October, 1987-2000. Results show that temperature modified ozone-mortality associations and that such modification varied across geographic regions. In the northeast region, a 10-ppb increment in ozone was associated with an increase of 2.22% (95% posterior interval [PI]: 1.19%, 3.13%), 3.06% (95% PI: 2.21%, 3.76%) and 6.22% (95% PI: 4.77%, 7.56%) in mortality at low, moderate and high temperature level, respectively, while in the southeast region a 10-ppb increment in ozone was associated with an increase of 1.13% (95% PI:-1.12%, 3.18%), 1.50% (95% PI: 0.22%, 2.81%) and 1.29% (95% PI:-0.33%, 2.96%) in mortality, respectively. We concluded that temperature synergistically modified the ozone-mortality association in the northeast region, but such a pattern was not apparent in the southeast region. Thus, both temperature and geographic factors should be considered in the assessment of ozone effects.  相似文献   
909.
大气环境中汞的形态及其分析方法   总被引:24,自引:0,他引:24  
陈乐恬  张晓山 《环境化学》1999,18(6):584-588
本文引用了近二十年来与大气环境中汞的形态和分析方法有关的20多篇文章,对各种方法的优缺点进行了比较。  相似文献   
910.
利用淡水发光菌评估电化学法处理模拟印染废水的效果   总被引:7,自引:0,他引:7  
童中华  廖军 《环境化学》1997,16(2):130-134
本研究利用新型淡水发光菌作为检测手段,对上种染料在电化学法处理模拟印染不过程中毒性的变化进行监测,结果表明,对工艺过程效果进行评估或对工业废水排放进行控制,仅仅采用化学参数的测试是不够的,应同时采用生物生测试手段。  相似文献   
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