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91.
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93.
针对我国现行的民航灾害应急联动救援体系所存在着多头指挥、组织形式不明确、责任关系不协调、信息沟通不顺畅、资源调度不合理等问题,运用文献检索、理论分析与实地调研相结合的方法,笔者提出优化思路:民航灾害应急联动机制应以各级民航管理当局的飞行事故应急指挥部为主要指挥决策者,采用虚拟的网络式组织形式,理顺联动单位的责任与关系,将应急联动的信息网络与各地突发公共危机事件的信息平台接轨,成立全国统一的、具有双重功能的民航灾害应急资源调度中心。其中,对民航灾害应急联动虚拟网络组织形式的设计,较好地改进了现行组织的效率,体现了快速反应和协调行动的要求。 相似文献
94.
Fredrick W. Kaurish Tamim Younos 《Journal of the American Water Resources Association》2007,43(2):533-545
Abstract: There is a significant need for a science‐based approach to interpret water‐monitoring data and to facilitate the rapid transfer of information to water resource managers and the general public. The water quality Index (WQI) is defined as a single numeric score that describes the surface water quality condition at a particular time and location. The objective of this paper is to describe the WQI concept and the approach for developing an ecoregion‐specific standardized WQI that meets the needs described above. The premise of the proposed WQI is based on categorizing scientifically documented aquatic life responses to changes in instream water chemistry. The method uses an aggregated procedure that matches the entire range of standardized probable biological responses to standardized narrative water quality evaluation categories and standardized rank score categories. The calculation of WQI and decision‐making process are performed within an Excel spreadsheet software program. The article includes examples of the proposed WQI applications that could enhance effective water resource management and facilitate timely communication of water quality conditions to water resource managers and the general public. 相似文献
95.
The study is primarily concerned with newspaper responses to flooding and erosion associated with Great Lakes high water in 1952–1953 and 1972–1974. Underlying the research is a general interest in informing the public more widely on choices available in resource and environmental decision making. 相似文献
96.
Adaptive governance to typhoon disasters for coastal sustainability: A case study in Guangdong,China
Globally, more people and assets are concentrated on the limited coastal plains where they are exposed to frequent disasters, such as typhoons, rainstorms and floods that often result in tremendous casualties and economic losses. Based on the causal analysis of the historical typhoon cases in the Guangdong Province of China, this study indicates that structural measures alone are not sufficient to resist and offset the impacts caused by typhoon disasters. Additionally, structural measures are unsustainable due to their high investment and low security. Adaptive governance, which uses non-structural measures and resilience building, is a feasible and cost-effective strategy for responding to the cascading effects of typhoon disasters. Multi-stakeholder participation and vertical–horizontal coordination are essential for providing adaptive governance to typhoon disasters. A risk-sharing model was put forward by bringing together the government, insurance companies and victims. Furthermore, a favorable atmosphere for public participation in disaster risk reduction can be fostered and should be a long-term adaptation strategy. The views and frameworks of adaptive governance provide policy makers with insights on coastal disaster risk management within the broader context of climate change. 相似文献
97.
为了降低火灾环境下储罐内部介质热响应及储罐失效试验研究的成本和风险,更好地为储罐事故的预测预防提供模拟依据,利用Fluent 12.0软件对密闭容器内部介质的传热传质过程进行模拟,给出了内部介质在受热和冷却条件下相变的控制方程;通过考虑内部介质气化热随温度的变化及饱和温度与区域单元压力之间的关系,编写了内部介质在受热和冷却条件下质量和能量源项的用户自定义函数(UDF);通过对部分参数进行简化,分别给出了喷射火和池火条件下丙烷储罐热响应模拟的结果,并与试验结果进行了对比.结果表明:储罐热响应各主要参数(内部介质温度、壁面温度,储罐内部压力)的误差在喷射火条件下低于15%,在池火条件下低于12.4%.这表明模拟所需源项UDF正确,可以用于现实储罐热响应的模拟. 相似文献
98.
采用微波诱导热解法制备低成本落叶吸附剂,以实现落叶的资源化利用.以碘吸附值为响应值,采用响应面分析法研究了微波诱导热解法制备落叶吸附剂的工艺条件.结果表明,热解时间与微波功率之间存在交互作用,当热解功率增加时,可适当缩短热解时间.落叶吸附剂的最佳制备工艺条件为:热解时间4.04 min,微波功率488.72W,氯化锌质量分数27%.落叶吸附剂以微孔吸附为主,BJH孔径分布较窄,孔容最高峰对应的孔径在1.9 nm左右,Langmuir比表面积为769.61 m2/g. 相似文献
99.
The supercritical fluid method, regarded as a type of individual production process in the course of preparing plant sterols, has become a promising technology, which possesses advantages of high conversion rate without any pretreatment and need of a catalyst. This study examined the reaction process of the deodorizer distillate (DOD), which mainly included the direct transesterification of DOD to convert into free sterols. The effects of the ratio of methanol to DOD, reaction temperature and time on transesterification were studied. Furthermore, the interactions between different factors were also assessed using the response surface methodology. The optimal conditions obtained were as follows: reaction temperature 553 K, reaction time 80 min, and CH3OH: DOD = 25:1 (mass ratio). Under these conditions, 36.42% sterol concentration was obtained, which is significantly higher in comparison with the initial sterols’ concentration in raw material (22.45%). 相似文献
100.
通过定位监测和样品跟踪采集,在旱季对喀斯特小流域连续20天无前期降雨的一场暴雨(累计降雨量64mm)水文水化学过程进行了动态监测,并分析了相关的影响因素。结果表明,小降雨事件(8.5mm)未能引起溪流水位、电导率及温度的明显变化,而当累计降雨量达到35.5mm后溪流水开始响应。此后,溪流水文水化学参数对降雨快速响应,除硝态氮外,电导率(EC)、δ18 O、Ca2+迅速降至最低值,雨水稀释作用对其水化学变化起主要作用。通过对溪流新旧水比例进行划分发现,降雨前期和后期,溪流以旧水补给为主,而在水位快速上涨阶段,新水比例达到34%左右。两次降雨过程中,在溪流水水位升高的情况下,水体中硝态氮浓度仍然表现出高于雨前浓度的趋势。该研究为该区旱季小流域水资源利用和污染物防治方面提供了一定理论依据。 相似文献