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With the acceleration of urbanisation in China, preventing and reducing the economic losses and casualties caused by urban rainstorm waterlogging disasters have become a critical and difficult issue that the government is concerned about. As urban storms are sudden, clustered, continuous, and cause huge economic losses, it is difficult to conduct emergency management. Developing a more scientific method for real-time disaster identification will help prevent losses over time. Examining social media big data is a feasible method for obtaining on-site disaster data and carrying out disaster risk assessments. This paper presents a real-time identification method for urban-storm disasters using Weibo data. Taking the June 2016 heavy rainstorm in Nanjing as an example, the obtained Weibo data are divided into eight parts for the training data set and two parts for the testing data set. It then performs text pre-processing using the Jieba segmentation module for word segmentation. Then, the term frequency–inverse document frequency method is used to calculate the feature items weights and extract the features. Hashing algorithms are introduced for processing high-dimensional sparse vector matrices. Finally, the naive Bayes, support vector machine, and random forest text classification algorithms are used to train the model, and a test set sample is introduced for testing the model to select the optimal classification algorithm. The experiments showed that the naive Bayes algorithm had the highest macro-average accuracy. 相似文献
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Risk assessment of rainstorm and flood disasters in China between 2004 and 2009 based on gray fixed weight cluster analysis 总被引：3，自引：0，他引：3
Rainstorm and flood disasters frequently occur in China, causing heavy losses for people’s lives and property and reducing the capability of sustainable development of the national and local economy. In this study, the risks of the rainstorm and flood disasters are assessed for the Chinese mainland, excluding Hong Kong, Macao, and Taiwan and also employ the historical data of seven indicators, including the affected area of crops, the affected population, the direct economic loss, and etc., from 2004 to 2009. Based on the large 1,302 historical sample data, the impact of rainstorm and flood disasters were analyzed using the methodology of gray fixed weight cluster analysis according to disaster losses, which were divided into the three gray classes of high, medium, and low. The regional differences of the risk assessment of the rainstorm and flood disasters are discussed, and the dynamical risk zoning map is conducted. The results show a consistent conclusion with the actual losses of rainstorm and flood disasters over each administrative district, which can provide more scientific evidence for the relevant departments of disaster prevention and mitigation. 相似文献
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研究了灰区间偏好的群体决策问题.在专家灰区间偏好群体意见集结过程中,常规的灰区间运算会产生决策信息的失真.为了避免这一缺陷,首先引入了灰区间调节参数的概念,通过建立求解调节参数的二次规划模型,确定专家灰区间判断的真值.建立了专家客观权重求解的二次规划模型,并给出了专家客观权重的最优解.此外,从另外一个角度同时考虑调节参数与客观权重,建立求解灰区间真值与专家客观权重的群体最优决策模型.气象敏感性行业专家群体评估决策的算例表明,决策策略是有效的. 相似文献
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Shah Ashfaq Ahmad Wu Wenya Gong Zaiwu Pal Indrajit Khan Jahangir 《Natural Hazards》2021,105(2):1977-2005
Natural Hazards - Children spend more than two-thirds of their total daytime in schools and becoming more persuasive in shielding them from potential hazards. Schools have a responsibility to... 相似文献
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In this paper, the data envelopment analysis (DEA) method is introduced to analyze the input–output efficiency of energy consumption and economic indicators in Beijing city under the influence of short-term climatic factors. Total energy consumption, fixed asset investment, average temperature, precipitation, sunshine hours, average wind velocity and the average pressure being employed as the input variables, gross domestic product (GDP) and per capita disposable income being employed as the output variables, effective technology and the validity of the scale of DEA of 31 decision-making units (DMUs) under the influence of the short-term climatic factors are analyzed, and the inefficient DMUs are improved. Empirical analysis shows that both energy consumption and economic growth are sensitive to short-term climate condition, and the reasonable employing of extreme climatic conditions is a question worthy of consideration. This study provides effective basis for the scientific and reasonable arrangement of Beijing city’s short-term climatic resources and energy–economic development. 相似文献
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This paper studies the border effects and sensitivity of the economic output of manufacturing in Jiangsu, China, caused by meteorological and environmental factors. The meteorological data, environmental data and annual manufacturing data of Jiangsu from 1993 to 2011 are used as input for this paper. Based on the Douglas production function and the grey correlation analysis method, this paper discusses the typical relationship among meteorological disaster factors, environmental regulations and the economic output of manufacturing in Jiangsu, China. The empirical analysis shows that the development of typical manufacturing in Jiangsu, China, is influenced by meteorological and environmental factors. 相似文献
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This paper analyzes the relationship between meteorological catastrophic factors and gross domestic product (GDP) growth rate of Nanjing city (China). The sample spans the period 1980–2010, including GDP growth rate and meteorological catastrophic factors (extreme precipitation, extreme temperature and extreme wind speed). We utilize econometric methods to take co-integration analysis and Granger causality test among GDP growth rate and the time series of meteorological catastrophic factors of Nanjing city processed by buffer operators. Finally, the paper shows the short-term changes in minimum atmospheric pressure, extreme high temperature, and minimum relative humidity, which has a positive impact on GDP; the cumulative effect of extreme precipitation and GDP affects each other to some extent, they are mutually Granger causes. Moreover, at the 95 % confidence level, we believe that maximum wind speed is the Granger causation of GDP growth rate. 相似文献
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In this paper, we introduce the gray correlation method of risk evaluation in meteorological disaster losses based on historical disaster data in China (mainland) and apply the improved gray relational analysis model (the triangular gray relational model) to the risk evaluation of rainstorm and flood disaster losses. In addition, we divide the risk grade standards of rainstorm and flood disaster losses according to 186 rainstorm and flood disaster data of four optimization indexes (disaster area, suffered population, collapsed houses, and direct economic losses), evaluate the extent of dynamic rainstorm and flood disaster losses in 31 provinces of China (Hong Kong, Macao, and Taiwan exclusive) comprehensively, and draw China’s zoning map of rainstorm and flood disaster from 2004 to 2009. The method provides reasonable and effective references for national disaster preventions which can be used in other researches focused on risk evaluation of meteorological disaster losses. 相似文献
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将数据包络分析法（DEA）应用于陕西气象资源效率评估,计算全省气象行业2007—2009年运行的综合效率值、技术效率值和规模效率值,得出综合效率和规模效率有所下降,而技术效率有所提升。其中,2009年技术效率均值为3年来最高,而2007年技术效率值为3年来最低。构造基于面板数据的气象计量经济模型对各影响效率的因素进行计量分析,气象服务用户群及公众满意度指数、农业产出GDP值占区域GDP总值的比重和资金投入强度与气象部门产出的综合效率值呈正向关系,学术论文发表数量与综合效率值呈反向关系。据此提出提升资源效率有效性的对策。 相似文献