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针对传统隐伏型导水地质裂缝勘探方法存在勘测精度较差的问题,提出电磁精细探测法探析隐伏型导水地质裂缝。依照屏蔽系数、实测场强和理论场强数据绘制综合曲线图,通过该图获取隐伏型导水地质裂缝所处位置几何阴影范围,采用层析成像法得到网格化的工作面,获取隐伏型导水地质图像。通过图像直接观测隐伏型导水地质工作面裂缝所处位置,在此基础上,观测四个电磁场分量,采用正交电磁场分量计算介质视电阻率,依据计算视电阻率数值和视电阻率分布状态研究裂缝发育情况和裂缝富水程度。结果表明:采用该方法能较为精准地获取隐伏型导水地质裂缝位置。通过裂缝位置进一步检测出隐伏型导水地质裂缝最大发育高度为63.5 m。当视电阻数值不断增加时,隐伏型导水地质裂缝和裂缝富水性逐渐减小,与实际情况较为相符,说明该种方法探析效果较好。  相似文献   
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注油结构是制约空调系统真空注油效率的关键因素之一.为研究三种常用注油结构的优劣性,采用试验方式分析测试了空调系统真空注油全过程中时间和压力变化情况.结果表明:截止阀和内螺纹注氟嘴形式的注油结构冷冻油充注效率较高;截止阀在安装/拆除接头等准备工作上所需时间普遍比注氟嘴多;真空注油的三个过程均会导致系统内部压力升高,影响后工序的实施效率.综合考虑冷冻油充注时间、操作效率和冷冻油灌注后系统压力回升因素,内螺纹注氟嘴为真空注油结构的最优选择.研究结果为空调系统注油结构设计提供了参考.  相似文献   
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Governance and Climate Vulnerability Index   总被引:1,自引:1,他引:0  
Water resources in the Middle East are under enormous stress, due to an increase in population growth and the extensive use of water resources, which exceeds the water demand in this regional bloc. Moreover, climatic changes pose another dimension of stress on water resources; these changes have significant environmental, social, and economic effects. In fact, the governance of these countries has the tendency of increasing this stress or decreasing it, depending on its performance and efficiency in applying policies, legislation and managerial plans towards decreasing the poverty and the vulnerability of the countries specially those suffering from poverty. In this paper, the vulnerability of five countries-Israel, Jordan, Lebanon, Palestine and Syria??will be assessed based on the extent of climate changes and the type of climate governance and their effects on water resources. This paper will introduce a new index, which will be called the Governance and Climate Vulnerability Index (GCVI). The index will measure the vulnerability of each country vis-à-vis water-related issues, while taking into account governance and climatic indicators. The vulnerability of these countries will also be ranked, for purposes of comparison. This paper concludes with the recommendation for governments to develop appropriate water resources management and to improve their environmental policies, including raising awareness on multiple levels. These strategies are expected to lead to decreased vulnerability to climatic changes.  相似文献   
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The promulgation of Environmental Quality (Clean Air) Regulations 2014 on emissions from coal-fired power plants in Malaysia has prompted power plant operators to adopt emission control strategy that complies with the new emission limits. Currently, various emission control strategies are available to achieve the desired emission level. Each strategy offers unique advantages and disadvantages, depending on the objective of emissions control, process nature, and constraints on the resources incurred. To address this challenge, a proper decision-making analysis needs to be performed. In this paper, a systematic decision analysis methodology is proposed to select the most effective multi-pollutant control strategy that is compatible for coal-fired power plants in Malaysia. The methodology includes: (1) identification of pollutant emission from the plant under study and comparison with the stipulated emission limits, (2) establishment of emission factors, (3) selection of multi-pollutant control strategy, (4) identification of emission reduction factor for the pollutants and control technologies of interest, (5) determination of emission level from the selected multi-pollutant control strategy, and (6) prediction of ground-level concentration of pollutants. The decision analysis methodology is applied to a real case study of coal-fired power plant in Malaysia, which also currently faces a dilemma to comply with the additional and more stringent emission limits stipulated in the Environmental Quality (Clean Air) Regulations 2014. The proposed method is applicable for both the process concept under the design phase as well as the existing process plant.  相似文献   
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Wireless Networks - This paper studies enhancing non-orthogonal multiple access (NOMA) spectral efficiency (SE) through optimizing the assigned power to each NOMA user depending on their channel...  相似文献   
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Journal of Applied Electrochemistry - A microbial fuel cell (MFC) is an electricity-generating device utilising electrochemically active microorganisms as biocatalysts. Using MFC as a biosensor to...  相似文献   
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