The major seismicity source in the northern Arabian Sea is the Makran Subduction Zone (MSZ) that defines the tectonic boundary between the Arabian plate and the Eurasian plate, located offshore Iran and Pakistan over ...The major seismicity source in the northern Arabian Sea is the Makran Subduction Zone (MSZ) that defines the tectonic boundary between the Arabian plate and the Eurasian plate, located offshore Iran and Pakistan over which an instrumentally registered earthquake (Mw 8.1) generated a tsunami on 27 November, 1945. It has caused severe cataclysm to a vulnerable population along the surrounding coastlines, including India. It has been on a long seismic quiescence since this last event. The population and industrialization have exponentially increased along the coastal areas in last half decade. The highly exposed coastal locations to the tsunamis are the areas where the nuclear power plants are located. In the present work, a numerical simulation of a great tsunamigenic earthquake (M 9) is presented that predicts the generation, propagation, run-up and travel time using TUNAMI N2 for estimating tsunami impacts along the nuclear power plants of the western coast of India. TUNAMI N2 code was designed for shallow water wave equations, which uses the finite-difference method based on staggered-leap frog scheme. Thus, it has potential to simulate a far-field tsunami with much more accuracy than other methods. It is observed that the tsunami will strike along the coast of Jaitapur Nuclear Power Plant (Maharashtra), Tarapur Nuclear Power Plant (Maharashtra), Kaiga Nuclear Power Plant (Karnataka) and Mithi-Virdi Nuclear Power Plant (Gujarat) after 210, 215, 225 and 230 minutes, respectively. Results show that the tsunami run-up is highest for Jaitapur coast (2.32 m). The Mithi-Virdi coast is the least effected (0.93 m) while Kaiga (2.15 m) and Tarapur coast (2.12 m) might have faced quite intense tsunami consequences. The arrival times and run-ups of the tsunami along the coast of different power plants have been calculated since these parameters are of vital importance in mitigation of the coastal hazard, evacuation planning and installation of early warning system in order to save the inhabited communities from the disaster.展开更多
针对核电安全仪控系统的安全完整性等级评定问题,借鉴IEC61508标准第六部分计算简单冗余结构失效概率的方法,对四取二冗余结构进行可靠性分析,提出一种面向工程应用的失效概率计算新方法 POPFA(Practice-oriented Probability of Failur...针对核电安全仪控系统的安全完整性等级评定问题,借鉴IEC61508标准第六部分计算简单冗余结构失效概率的方法,对四取二冗余结构进行可靠性分析,提出一种面向工程应用的失效概率计算新方法 POPFA(Practice-oriented Probability of Failure Analysis)。并以数字化核电安全仪控系统TXS的四取二冗余结构为计算实例,与Markov方法进行比较,验证了计算结果正确并且计算复杂度远小于Markov方法,适用于实际工程运行中失效概率的计算。展开更多
Air pollution and climate change are two important threats facing in our planet and are tightly linked to carbonaceous components in the atmosphere.A better understanding of the emission sources and environmental fate...Air pollution and climate change are two important threats facing in our planet and are tightly linked to carbonaceous components in the atmosphere.A better understanding of the emission sources and environmental fate/sink of carbonaceous components is critical for improving our knowledge of the global carbon cycle and mitigating the negative environmental impacts of air pollution and climate change on human well-being.Radiocarbon(^(14)C),which is decayed completely in fossil fuel(e.g.coal and petroleum),is an ideal tool for quantifying the carbon flow in various carbon reservoirs.This study reviews the current knowledge of 14C in organic carbon(OC),elemental carbon(EC),individual organic compounds,methane(CH_(4)),carbon dioxide(CO_(2)),annual plants,and tree rings.The impacts of fossil and non-fossil sources on the atmosphere can be quantified by measuring^(14)C.We also report on the influence of nuclear power plants and sea-air gas exchange on the abundance of^(14)C in the atmosphere.The increasing fossil fuel emissions indicated by the depletion of^(14)CO_(2)under IPCC RCP scenarios,support the urgent need to devise ambitious strategies of reducing carbonaceous components to achieve sustainable development on Earth.This review summarizes the challenges and perspectives of 14C studies of the atmosphere.展开更多
文摘The major seismicity source in the northern Arabian Sea is the Makran Subduction Zone (MSZ) that defines the tectonic boundary between the Arabian plate and the Eurasian plate, located offshore Iran and Pakistan over which an instrumentally registered earthquake (Mw 8.1) generated a tsunami on 27 November, 1945. It has caused severe cataclysm to a vulnerable population along the surrounding coastlines, including India. It has been on a long seismic quiescence since this last event. The population and industrialization have exponentially increased along the coastal areas in last half decade. The highly exposed coastal locations to the tsunamis are the areas where the nuclear power plants are located. In the present work, a numerical simulation of a great tsunamigenic earthquake (M 9) is presented that predicts the generation, propagation, run-up and travel time using TUNAMI N2 for estimating tsunami impacts along the nuclear power plants of the western coast of India. TUNAMI N2 code was designed for shallow water wave equations, which uses the finite-difference method based on staggered-leap frog scheme. Thus, it has potential to simulate a far-field tsunami with much more accuracy than other methods. It is observed that the tsunami will strike along the coast of Jaitapur Nuclear Power Plant (Maharashtra), Tarapur Nuclear Power Plant (Maharashtra), Kaiga Nuclear Power Plant (Karnataka) and Mithi-Virdi Nuclear Power Plant (Gujarat) after 210, 215, 225 and 230 minutes, respectively. Results show that the tsunami run-up is highest for Jaitapur coast (2.32 m). The Mithi-Virdi coast is the least effected (0.93 m) while Kaiga (2.15 m) and Tarapur coast (2.12 m) might have faced quite intense tsunami consequences. The arrival times and run-ups of the tsunami along the coast of different power plants have been calculated since these parameters are of vital importance in mitigation of the coastal hazard, evacuation planning and installation of early warning system in order to save the inhabited communities from the disaster.
文摘针对核电安全仪控系统的安全完整性等级评定问题,借鉴IEC61508标准第六部分计算简单冗余结构失效概率的方法,对四取二冗余结构进行可靠性分析,提出一种面向工程应用的失效概率计算新方法 POPFA(Practice-oriented Probability of Failure Analysis)。并以数字化核电安全仪控系统TXS的四取二冗余结构为计算实例,与Markov方法进行比较,验证了计算结果正确并且计算复杂度远小于Markov方法,适用于实际工程运行中失效概率的计算。
基金This research was supported by the National Natural Science Foundation of China(Nos.42030715,41877349)Guangdong Foundation for Program of Science and Technology Research(Nos.2017BT01Z134,2019B121205006)National Key R&D Program of China(2017YFC0212000).
文摘Air pollution and climate change are two important threats facing in our planet and are tightly linked to carbonaceous components in the atmosphere.A better understanding of the emission sources and environmental fate/sink of carbonaceous components is critical for improving our knowledge of the global carbon cycle and mitigating the negative environmental impacts of air pollution and climate change on human well-being.Radiocarbon(^(14)C),which is decayed completely in fossil fuel(e.g.coal and petroleum),is an ideal tool for quantifying the carbon flow in various carbon reservoirs.This study reviews the current knowledge of 14C in organic carbon(OC),elemental carbon(EC),individual organic compounds,methane(CH_(4)),carbon dioxide(CO_(2)),annual plants,and tree rings.The impacts of fossil and non-fossil sources on the atmosphere can be quantified by measuring^(14)C.We also report on the influence of nuclear power plants and sea-air gas exchange on the abundance of^(14)C in the atmosphere.The increasing fossil fuel emissions indicated by the depletion of^(14)CO_(2)under IPCC RCP scenarios,support the urgent need to devise ambitious strategies of reducing carbonaceous components to achieve sustainable development on Earth.This review summarizes the challenges and perspectives of 14C studies of the atmosphere.
