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1.
用灰色模型预测我国铁路水害发展趋势   总被引:2,自引:0,他引:2  
周华国  魏庆朝 《灾害学》1996,11(2):23-27
根据近15a来我国铁路水害年断道时间和断道次数的数据特点,将不同程度水害年分为三个等级。在此基础上,建立了铁路水害的灰色预测模型。并用此模型预测了近期铁路水害大小和远期的发展趋势。这对于我国铁路水害防治的宏观决策具有指导意义。  相似文献   
2.
东亚春季边界层臭氧的数值模拟研究   总被引:3,自引:2,他引:3  
利用嵌套网格空气质量模式系统(NAQPMS)对2004年4月东亚边界层(距地面.km以下)臭氧进行了数值模拟.并评估了东亚边界层光化学反应的活性.结果表明.东亚春季臭氧呈带状分布,其高值.〔φ(O3)>55×10-9.主要集中在30°N~40°N.受东亚季风气候控制.沿蒙古、中国东北以及日本一线有一强臭氧输送通道.输送通量达3×10-.mol/(m2·s).通过计算边界层O3光化学净生成率可知.光化学影响主要集中在高污染源排放地区.其与水平输送对臭氧影响的分布具有负相关性.说明光化学生成的O3可被输送至下风地区,而不仅限于局地.   相似文献   
3.
Importance Measures (IMs) are used to rank the contributions of components or basic events to the system performance, e.g. its reliability or risk. Most times, IMs are calculated without due account of the uncertainties in the model of the behavior of the system. The objective of this work is to investigate how uncertainties can influence IMs and to develop a method for giving them due account in the corresponding ranking of the components or basic events. The uncertainties considered in this work affect the model parameters values and are assumed to be described by probability density functions. The method for ranking the contributors to the system performance measure is applied to the auxiliary feedwater system of a nuclear pressurized water reactor.  相似文献   
4.
实现2030年碳排放达峰不仅是中国为应对全球气候变化向国际社会做出的郑重承诺,也是中国未来经济结构转型与可持续发展的必然选择。基于中国实现2030年碳排放达到峰值的宏观目标为背景,本文以中国碳排放的主要行业工业为研究对象,首先运用拓展的STIRPAT模型对工业及其9个细分行业的碳排放达峰进行了情景预测,然后基于公平和效率的双重视角对工业细分行业的减排潜力进行评估。研究表明:(1)仅有低碳情景和抑制排放情景2可以实现中国碳排放2030年达峰,低碳情景是实现中国工业碳排放达峰的最佳发展模式,达峰时间最早(2030年),峰值最低(140.43亿t)。激进排放情景则是最差的发展模式,达峰时间最晚(2036年),峰值也最高(150.09亿t)。(2)工业内部各细分行业碳排放的最优达峰情景差别较大。建材和纺织制造业能够实现提前达峰,可以在这类行业率先实施达峰管理措施,使其带动其他行业陆续达峰。(3)最具减排潜力的行业是石油制造业,其次是电力行业,这些减排潜力较大的行业应该成为国家节能减排的重点对象。(4)基于工业各细分行业在减排公平性和效率性上的差异将工业9个细分行业分为四类。其中,石油、钢铁制造业和电力行业属于"高效高公平行业";化工、建材制造业属于"低效高公平行业";采掘业属于"高效不公平行业";纺织、轻工和机电制造业属于"低效不公平行业"。中国应针对不同类型的行业制定出相应的减排战略,将减排重点放在各行业最具潜力的方面。最后,文章对实现中国工业碳排放达峰管理提出了几点政策建议。  相似文献   
5.
In the last two decades, several serious accidents at large-scale technological systems that have had grave consequences, such as that at Bhopal, have primarily been attributed to human error. However, further investigations have revealed that humans are not the primary cause of these accidents, but have inherited the problems and difficulties of working with complex systems created by engineers. The operators have to comprehend malfunctions in real time, respond quickly, and make rapid decisions to return operational units to normal conditions, but under these circumstances, the mental workload of operators rises sharply, and a mental workload that is too high increases the rate of error. Therefore, cognivitive human features such as situation awareness (SA)—one of the most important prerequisite for decision-making—should be considered and analyzed appropriately. This paper applys the SA Error Taxonomy methodology to analyze the role of SA in three different accidents: (1) A runaway chemical reaction at Institute, West Virginia killing two employees, injuring eight people, and requiring the evacuation of more than 40,000 residents adjacent to the facility, (2) The ignition of a vapor cloud at Bellwood, Illinois that killed one person, injured two employees, and caused significant business interruption, and (3) An explosion at Ontario, California injuring four workers and caused extensive damage to the facility. In addition, the paper presents certain requirements for cognitive operator support system development and operator training under abnormal situations to promote operators’ SA in the process industry.  相似文献   
6.
This paper compares predictions of the foodchain model SPADE with experimental data for the transfer of (134)Cs and (85)Sr to strawberry plants following acute foliar and soil contamination. The transfer pathways considered in this exercise included direct deposition to fruit, leaf-to-fruit, soil-to-leaf and soil-to-fruit transfers. Following foliar contamination, the difference between predicted and measured radionuclide activity values varied between a factor of 0.5-10 for fruit and 4.5-7 for leaf. Following soil contamination, the difference between predicted and measured values varied between a factor of 3-74 for fruit and 32-44 for leaf. In all cases the difference between measured and predicted values was smaller for (85)Sr than (134)Cs. Measured and predicted activities were higher for leaf than fruit. Both measured and predicted (134)Cs concentrations in fruit and leaf are higher when deposition occurs at ripening than at anthesis. These results confirm the need for more data on fruit, even for Cs and Sr, to support models in predicting the transfer of radionuclides to fruit crops. Ongoing research projects funded by the UK Food Standards Agency aim to provide some data on radionuclide transfer to herbaceous, shrub and tree fruits, which will help improve radiological assessment models in order to provide better protection for consumers.  相似文献   
7.
Uncertainty plays a major role in Integrated Coastal Zone Management (ICZM). A large part of this uncertainty is connected to our lack of knowledge of the integrated functioning of the coastal system and to the increasing need to act in a pro-active way. Increasingly, coastal managers are forced to take decisions based on information which is surrounded by uncertainties. Different types of uncertainty can be identified and the role of uncertainty in decision making, scientific uncertainty and model uncertainty in ICZM is discussed. The issue of spatial variability, which is believed to be extremely important in ICZM and represents a primary source of complexity and uncertainty, is also briefly introduced. Some principles for complex model building are described as an approach to handle, in a balanced way, the available data, information, knowledge and experience. The practical method of sensitivity analysis is then introduced as a method for a posterior evaluation of uncertainty in simulation models. We conclude by emphasising the need for the definition of an analysis plan in order to handle model uncertainty in a balanced way during the decision making process.  相似文献   
8.
抚顺市大气污染物对降水pH值的影响及预测分析   总被引:1,自引:0,他引:1  
降水 pH值在一定程度上反映了降水和大气的污染状况。研究抚顺市大气污染物对降水 pH值的影响并预测了未来几年降水 pH值的变化趋势。结果表明 :抚顺市的降水酸度是由大气中的SO2 等酸性气体和碱性尘埃共同作用的结果 ,降水 pH值向酸性降水发展。  相似文献   
9.
针对存在补给关系的河流或河段,提出更切合实际设计条件的水量平衡模型和水量水质平衡模型,进而确定了源与目标之间的响应关系参数和河流或河段的输移作用,在水量水质平衡模型基础上,给出推求自净环境容量的方法。该模型和方法已得到实际应用和检验,具有广泛的应用前景。   相似文献   
10.
高斯轨迹烟云扩散模型在贵阳空气质量预报中的应用   总被引:4,自引:0,他引:4  
选择在复杂地区应用较好的高斯轨迹烟云扩散模型,作为贵阳市空气质量预报的数学扩散模式,并利用贵阳市现有的污染源排放资料和气象资料,对贵阳市的大气污染物分布进行了模拟计算,经与实测结果比较表明:实测值与监测值基本一致,相关性较好。该模式可以作为贵阳市空气质量预报的数学扩散模式,对其他城市也具有一定的借鉴作用。   相似文献   
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