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521.
The technology of correspondence analysis was applied to high-casualty fire data in China. The aim of this study was to investigate the associations between fatality levels and influence factors that involve place, cause, time of day, month, year and province. The variable fatality in a fire has four levels: 3, 4-5, 6-9 and ?10. The results show that hotels, welfare houses and hospitals tend to be strongly associated with fatality level ?10. The fires caused by work-related tasks tend to precipitate a relatively high number of fatalities and are strongly associated with fatality level 6-9. Fires that occur in the daytime (8:00-19:59) are associated with higher fatalities than fires that occur at night (20:00-7:59). The months in the cold season, such as winter or the beginning of spring, tend to be associated with fatality levels 4-5, 6-9 and ?10. CA dynamically portrayed the fatality tendency over the past 8 years, and 2007 tended to be associated with fatality level ?10. Fatality characteristics of provinces are identified, and Beijing, Shandong and Jilin are strongly associated with fatality level ?10. To explore whether associations between influence factors and fatality levels of high-casualty fires in China resemble corresponding associations of HCFs in the United States, data on fires with fatality level ?5 in the two countries were collected. The results of four sets of comparisons indicate that the associations between influences and fatality levels in the two countries present contrasting features. Some practical applications are briefly discussed. 相似文献
522.
恒压变频调速给水方式已普遍被采用,但作为应用在民用建筑供水上的新方式,对其深入研究不多。导致实际使用效果参差不齐。指出了恒压变频调速方式应用在民用建筑供水上出现的问题,详细分析了出现问题的原因,并提出了解决办法。 相似文献
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有毒气体泄漏扩散受很多不确定性因素的影响,为了分析和评估影响毒气泄漏扩散的风速和泄漏速率的变化和不确定性,采用蒙特卡罗模拟和基于Wilks公式容许限的非参数统计法,通过抽样计算得到“95/95准则”下的毒气泄漏扩散地面浓度分布,计算了有毒气体泄漏扩散的不同风险等级的影响范围和风险概率曲线。以氨气泄漏事故为例进行实例分析,结果表明,相对于以确定性参数得出的氨气泄漏扩散浓度分布,引入参数的不确定性评估,更能贴合泄漏现场存在不确定性因素的实际情况,更有利于人员的安全和应急疏散管理。 相似文献
526.
浅论"三表合一"的设想 总被引:1,自引:0,他引:1
毛应淮 《中国环境管理干部学院学报》2004,14(3):71-74
对国家环保总局提出的"三表合一"的设想,从三个方面提出自己的观点。第一,应以排污申报登记核定为基础,客观建立污染源动态数据库;第二,"三表合一"应该是环境统计报表、排污收费报表、污染控制报表等各方面污染源的数据统一到排污申报登记报表;第三,"三表合一"首先应建立统一的污染源指标体系,统一的污染测算方法和统一的基础数据库。 相似文献
527.
ABSTRACT: A strategy for formulating and testing the Poisson partial duration extreme value model is presented. The procedure is demonstrated using recorded Streamflow series from a humid subtropical region of the southern United States. The observed data series are partitioned by climatic causes and tested for both the Poisson assumption and the validity of the exponential as marginal distributions. Several statistical tests are utilized in making these determinations. Some important aspects of the model as applied to humid climates are demonstrated. It was found that a majority of Streamflow series could be represented by the model and that significant differences do exist between the arrival structures of floods resulting from different climatic mechanisms. However, these differences generally do not exist in the distribution of the flood magnitudes. In addition, it is possible that model validity is restricted by drainage basin size. 相似文献
528.
ESTABLISHING STATISTICAL DESIGN CRITERIA FOR WATER QUALITY MONITORING SYSTEMS: REVIEW AND SYNTHESIS1
Robert C. Ward Jim C. Loftis 《Journal of the American Water Resources Association》1986,22(5):759-767
ABSTRACT: Regulatory water quality management has placed fairly extensive information expectations on routine, fixed-station monitoring without a corresponding emphasis being placed on the need to design monitoring systems to meet these expectations. To correct the situation there is increasing interest in developing more quantitative monitoring system design procedures which incorporate the statistical nature of sampling. In examining the development of such quantitative criteria, this paper describes the roles of statistics in a systematic approach to monitoring - initial design and routine reporting of results - and reviews the use of statistics in each. The paper emphasizes the need to tie the two together, via statistical design criteria, in order for the identified information expectations to be met in a statistically sound manner. However, the use of statistics in water quality monitoring is noted as currently being as much an art as it is a science. 相似文献
529.
Vijay P. Singh Kulwant Singh 《Journal of the American Water Resources Association》1987,23(6):1185-1189
ABSTRACT: The principle of maximum entropy (POME) was used to derive an alternative method for parameter estimation for the three parameter lognormal (TPLN) distribution. Six sets of annual peak discharge data were used to evaluate this method and compare it with the methods of moments and maximum likelihood estimation. 相似文献
530.
Yeou-Koung Tung Larry W. Mays 《Journal of the American Water Resources Association》1981,17(2):262-269
ABSTRACT: In order to promote a uniform and consistent approach for floodflow frequency studies, the U.S. Water Resources Council has recommended the use of the log-Pearson type III distribution with a generalized skew coefficient. This paper investigates various methods of determining generalized skew coefficients. A new method is introduced that determines generalized skew coefficients using a weighting procedure based upon the variance of regional (map) skew coefficients and the variance of sample skew coefficients. The variance of skew derived from sample data is determined using either of two non-parametric methods called the jackknife or bootstrap. Applications of the new weighting procedure are presented along with an experimental study to test various weighting procedures to derive generalized skew coefficients. 相似文献