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31.
In 1999, two earthquakes in northwest Turkey caused heavy damage to a large number of industrial facilities. This region is the most industrialized in the country, and heavy damage has a significant economic influence. Industrial storage tanks, ruptured by earthquakes, exascerbate damage through the spread of fire. Storage tanks are uniquely structured, tall cylindrical vessels, some supported by relatively short reinforced concrete columns. The main aim of this study is to evaluate the earthquake performance of Turkish industrial facilities, especially storage tanks in terms of earthquake resistance. Modeling a typical storage tank of an industrial facility helps to understand the structure’s seismic response. A model tank structure was modelled as a solid with lumped mass and spring systems. Performance estimation was done with 40 different earthquake data through nonlinear time history analyses. After the time history analyses, fragility analyses produced probabilistic seismic assessment for the tank model. For the model structure, analysis results were evaluated and compared. In the study, vulnerability of storage tanks in Turkey was determined and the probabilistic risk was defined with the results of the analysis.  相似文献   
32.
1949—1994年中国洪水灾害成灾面积的时序分形特征   总被引:24,自引:3,他引:24  
作者应用1949~1994年中国洪水灾情资料,重构了其嵌入相空间序列,探讨了其时序的分形特征,计算得到了分维数。研究表明:洪水灾害成灾面积的时序分布具有分形特征。研究结果为建立洪水灾害成灾面积的时序预测预报模型提供依据。  相似文献   
33.
To determine the population exposure to PM(10) in Chongqing, China, we developed an indirect model by combining information on the time activity patterns of various demographic subgroups with estimates of the PM(10) concentrations in different microenvironments (MEs). The spatial and temporal variations of the exposure to PM(10) were illustrated in a geographical information system (GIS). The population weighted exposure (PWE) for the entire population was 229, 155 and 211 microg/m(3), respectively, in winter, summer and as the annual average. Indoor PM(10) level at home was the largest contributor to the PWE, especially for the rural areas where high pollution levels were found due to solid fuels burning. Elder people had higher PM(10) exposure than adults and youth, due to more time spent in indoor MEs. The highest health risk due to particulate was found in the city zone and northeast regions, suggesting that pollution abatement should be prioritized in these areas.  相似文献   
34.
The herbicide, glyphosate, has been shown to stimulate growth in a range of species when applied at doses of 5-60 g a.e. ha−1, corresponding to realistic spray drift events. This study investigates growth of shoot parameters over time to detect whether the glyphosate induced growth increase was sustained and had a final effect on reproduction. The results showed that an actual biomass growth rate increase took place within the first week after spraying with glyphosate doses <60 g a.e. ha−1. This initial growth boost kept treated plants larger than untreated plants for up to six weeks, but at harvest there was no significant difference between control plants and treated plants. Possible effects of glyphosate hormesis on the competitive ability of spray drift affected plants are discussed.  相似文献   
35.
蠕变-样条联合模型及其在滑坡时间预报中的应用   总被引:1,自引:0,他引:1  
根据滑坡演化的一般规律并考虑到外动力因素对斜坡变形破坏的影响,提出了一种蠕变与样条的联合模型。通过新滩滑坡和链子崖危岩体的实例分析,采用蠕变-样条联合模型进行滑坡位移数据分析和临滑时间预报。初步研究表明,联合模型与其它模型相比具有使用方便和精度高等优点  相似文献   
36.
Ghoramara Island is located ca. 150 km south of Kolkata, Bay of Bengal, India, in the Sundarban Delta complex. This sparsely populated island is suffering from severe coastal erosion and areal reduction for the last three decades, which results in the loss of major areas on the northwest coast. Both numerous households and a significant area of agricultural land and coastal stretches for fish drying have been lost. This has rendered thousands of people homeless as ‘environmental refugess’. In the present paper an attempt is made to study the erosion and accretion process through time series analysis using a GIS technique. Also, a study of remedial measures to protect the island using a ‘bio-engineering’ technique is reported in this paper. It has been shown that, in the absence of protection measures, the eastern shore will merge with the Indian mainland during the next 25 years, while the western part will be completely washed off.  相似文献   
37.
SBR生物反应器出水溶解态有机物性质特点研究   总被引:2,自引:0,他引:2  
研究中考察了SBR生物反应器处理实际生活污水过程中,反应器内部溶解性有机物的变化情况,重点分析了污泥龄对于SBR反应器出水溶解态有机物性质特点的影响.研究结果表明,生物降解过程中,以分子量650Da、1700Da和2000Da为代表的腐殖质类有机物逐渐积累,小分子量有机物(<200Da)逐渐转化为具有中间分子量(500...  相似文献   
38.
大气环境数据分析预测方法对比研究   总被引:3,自引:2,他引:1  
以西安市2006年9月27日至2008年5月3日每日的SO2平均浓度时间序列为例,应用时间序列分析对前555个数据进行拟合,得到合适的时间序列模型ARIMA(1,1,2);利用神经网络中的BP神经网络和RBF神经网络对同样的样本进行训练,用这三种方法对2008年4月4日至2008年5月3日的SO2日均浓度值进行了预测,并用同样的方法分析预测了同期PM10日均浓度值,最后比较了它们的预测效果。结果表明,利用这三种方法进行浓度预测都是可行的,其中RBF神经网络法的预测误差最小,效果最好。  相似文献   
39.
周家斌 《灾害学》1991,6(2):22-27,64
本文叙述了作者提出的时间序列预报方法的基本原理,介绍了这一方法在应用过程中的发展及在实际部门应用的情况,其中包括异常旱涝灾害预报及方法的改进等最新成果。  相似文献   
40.
Japan Atomic Energy Research Institute has developed an emergency response system WSPEEDI to forecast long-range atmospheric dispersions of radionuclides discharged into the atmosphere. The latest version of WSPEEDI consists of an atmospheric dynamic model MM5 for calculating meteorological fields and a particle random-walk model for atmospheric dispersion. The performance of WSPEEDI was evaluated by data obtained from a field tracer experiment over Europe (ETEX) in this paper. The model validation was done with respect to the following points: (1) the dependence of model accuracy on the temporal and spatial resolutions of the meteorological fields and (2) the superiority of an atmospheric dynamic model over a mass-consistent wind model. Regarding (1), it was shown that the calculation accuracy of the new version with high temporal resolution was improved, especially at the edge of the plume. Moreover, although the increase in horizontal spatial resolution of the old version had no substantial effect on the model performance, increase in horizontal resolution of the new version contributed to the significant improvement of the calculation accuracy. These results showed that the dynamically calculated meteorological field with the spatial resolution of the meso-βγ scale greatly improved calculation accuracy.  相似文献   
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