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71.
Keisuke Himoto 《Risk analysis》2020,40(6):1124-1138
Post-earthquake fires are high-consequence events with extensive damage potential. They are also low-frequency events, so their nature remains underinvestigated. One difficulty in modeling post-earthquake ignition probabilities is reducing the model uncertainty attributed to the scarce source data. The data scarcity problem has been resolved by pooling the data indiscriminately collected from multiple earthquakes. However, this approach neglects the inter-earthquake heterogeneity in the regional and seasonal characteristics, which is indispensable for risk assessment of future post-earthquake fires. Thus, the present study analyzes the post-earthquake ignition probabilities of five major earthquakes in Japan from 1995 to 2016 (1995 Kobe, 2003 Tokachi-oki, 2004 Niigata–Chuetsu, 2011 Tohoku, and 2016 Kumamoto earthquakes) by a hierarchical Bayesian approach. As the ignition causes of earthquakes share a certain commonality, common prior distributions were assigned to the parameters, and samples were drawn from the target posterior distribution of the parameters by a Markov chain Monte Carlo simulation. The results of the hierarchical model were comparatively analyzed with those of pooled and independent models. Although the pooled and hierarchical models were both robust in comparison with the independent model, the pooled model underestimated the ignition probabilities of earthquakes with few data samples. Among the tested models, the hierarchical model was least affected by the source-to-source variability in the data. The heterogeneity of post-earthquake ignitions with different regional and seasonal characteristics has long been desired in the modeling of post-earthquake ignition probabilities but has not been properly considered in the existing approaches. The presented hierarchical Bayesian approach provides a systematic and rational framework to effectively cope with this problem, which consequently enhances the statistical reliability and stability of estimating post-earthquake ignition probabilities. 相似文献
72.
AbstractOne of the basic statistical methods of dimensionality reduction is analysis of discriminant coordinates given by Fisher (1936) and Rao (1948). The space of discriminant coordinates is a space convenient for presenting multidimensional data originating from multiple groups and for the use of various classification methods (methods of discriminant analysis). In the present paper, we adapt the classical discriminant coordinates analysis to multivariate functional data. The theory has been applied to analysis of textural properties of apples of six varieties, measured over a period of 180?days, stored in two types of refrigeration chamber. 相似文献
73.
杨晓培 《西南石油大学学报(社会科学版)》2015,34(6):118-122
在沉积微相、储层物性特征分析的基础上,选取孔隙度、渗透率、流动带指数等参数,对泌阳凹陷赵凹油田泌301 井区核三段油层组进行流动单元划分。依据流动带指数的大小,将研究区目的层段划分为A、B、C、D 和E 等5 类流动单元。通过研究发现,各类流动单元与物性、岩性、沉积微相之间具有较好的对应关系,同时对不同流动单元产能进行了分析。研究结果表明,流动单元的划分能够真实客观地反映储层物性差、非均质性强的地质特点,单井产能与流动带指数有较好的乘幂关系,不同流动单元产能差异较为明显,物性最好的A 类流动单元产能最高,物性最差的E类流动单元产能最低。 相似文献
74.
2008年5月12日,举国震动的汶川大地震打破了平静,灾区人民的生命财产遭受巨大损失。灾后重建,八方支援,灾区人民找回失去的幸福。文章采用问卷调查地震灾区重建后家庭幸福感状况,从物质生活幸福感、环境幸福感和精神生活幸福感三因子反映地震后家庭幸福指数,构建因子模型,以期向爱心人士提供灾后重建的家庭幸福感的可靠信息。 相似文献
75.
This article presents an asset‐level security risk management framework to assist stakeholders of critical assets with allocating limited budgets for enhancing their safety and security against terrorist attack. The proposed framework models the security system of an asset, considers various threat scenarios, and models the sequential decision framework of attackers during the attack. Its novel contributions are the introduction of the notion of partial neutralization of attackers by defenders, estimation of total loss from successful, partially successful, and unsuccessful actions of attackers at various stages of an attack, and inclusion of the effects of these losses on the choices made by terrorists at various stages of the attack. The application of the proposed method is demonstrated in an example dealing with security risk management of a U.S. commercial airport, in which a set of plausible threat scenarios and risk mitigation options are considered. It is found that a combination of providing blast‐resistant cargo containers and a video surveillance system on the airport perimeter fence is the best option based on minimum expected life‐cycle cost considering a 10‐year service period. 相似文献
76.
We propose a typology of different meanings of cohabitation that combines cohabiters’ intentions to marry with a general attitude toward marriage, using competing risk analyses to examine whether some cohabiters are more prone than others to marry or to separate. Using data (N = 1,258) from four waves of the German Family Panel (PAIRFAM) and a supplementary study (DEMODIFF), we compared eastern and western German cohabiters of the birth cohorts 1971–73 and 1981–83. Western Germans more frequently view cohabitation as a step in the marriage process, whereas eastern Germans more often cohabit as an alternative to marriage. Taking into account marital attitudes reveals that cohabiters without marriage plans differ from those with plans in their relationship careers, and also shows that cohabiters who plan to marry despite holding a less favourable view of marriage are less likely to realize their plans than cohabiters whose intentions and attitudes are more congruent. 相似文献
77.
Although attitudes toward homosexuality have become more liberal, particularly in industrialized Western countries, there is still a great deal of variance in terms of worldwide levels of homonegativity. Using data from the two most recent waves of the World Values Survey (1999–2004, 2005–2009), this article seeks to explain this variance by means of a multilevel analysis of 79 countries. We include characteristics on the individual level, as age or gender, as well as aggregate variables linked to specificities of the nation-states. In particular, we focus on the religious denomination of a person and her religiosity to explain her attitude toward homosexuality. We find clear differences in levels of homonegativity among the followers of the individual religions. 相似文献
78.
丁金胜 《青岛农业大学学报(社会科学版)》2015,(2)
运用SWOT 分析法对青岛市乡村休闲旅游发展进行分析,结果显示:青岛具有资源丰富、经济发达、交通便利等优势,但同时也存在认识水平不高、农村基础设施落后、产品同质化严重、季节性明显、人才缺乏等劣势;面临旅游新热点形成、政府出台鼓励政策、新型农村社区的建设等新的发展机遇,但周边地区的竞争、生态环境的恶化也对其构成了威胁。在此基础上,提出了提高认识水平、完善基础设施、打造特色品牌、保护资源、培养人才等可行性建议。 相似文献
79.
《Women and birth : journal of the Australian College of Midwives》2015,28(3):e31-e35
BackgroundThe Edinburgh Postnatal Depression Scale (EPDS) is well accepted for detecting symptoms of postnatal depression. The aim of this study was to examine psychometric properties and to evaluate structural models of the Serbian translation of EPDS in pregnant and postpartum women.MethodsThe original English version of the EPDS was translated into Serbian, and checked by means of back-translation. Data were collected via an anonymous online questionnaire posted on a Serbian website devoted to pregnancy topics. The study sample included 201 women (76 pregnant, 125 postpartum). The internal consistency of the scale was measured by Cronbach's α coefficient. Principal component analysis was used to determine scale dimensions while confirmatory factor analysis was used to evaluate model fit.FindingsCronbach α coefficient was 0.84 and 0.83 in pregnant and postpartum women, respectively, which indicated good internal consistency of the Serbian EPDS. Three dimensions of the scale were revealed in both groups of women. Goodness of fit indices described good and excellent model in pregnant and postpartum women, respectively. High level of depression symptoms (score ≥13) was recorded in 27.6% and 24.8% (p > 0.05) of pregnant and postpartum women, respectively. Moderate level of depression symptoms (score 10–12) was recorded in 21.1% and 16.8% (p > 0.05) of pregnant and postpartum women, respectively.ConclusionThe Serbian translation of the EPDS showed good consistency and good model characteristics in pregnant and postpartum women. However, cut-off values, sensitivity and specificity of the scale should be determined in the further studies with more representative samples of women. 相似文献
80.
Evaluation of Inhaled Versus Deposited Dose Using the Exponential Dose‐Response Model for Inhalational Anthrax in Nonhuman Primate,Rabbit, and Guinea Pig 下载免费PDF全文
Bradford W. Gutting Andrey Rukhin Ryan S. Mackie David Marchette Brandolyn Thran 《Risk analysis》2015,35(5):811-827
The application of the exponential model is extended by the inclusion of new nonhuman primate (NHP), rabbit, and guinea pig dose‐lethality data for inhalation anthrax. Because deposition is a critical step in the initiation of inhalation anthrax, inhaled doses may not provide the most accurate cross‐species comparison. For this reason, species‐specific deposition factors were derived to translate inhaled dose to deposited dose. Four NHP, three rabbit, and two guinea pig data sets were utilized. Results from species‐specific pooling analysis suggested all four NHP data sets could be pooled into a single NHP data set, which was also true for the rabbit and guinea pig data sets. The three species‐specific pooled data sets could not be combined into a single generic mammalian data set. For inhaled dose, NHPs were the most sensitive (relative lowest LD50) species and rabbits the least. Improved inhaled LD50s proposed for use in risk assessment are 50,600, 102,600, and 70,800 inhaled spores for NHP, rabbit, and guinea pig, respectively. Lung deposition factors were estimated for each species using published deposition data from Bacillus spore exposures, particle deposition studies, and computer modeling. Deposition was estimated at 22%, 9%, and 30% of the inhaled dose for NHP, rabbit, and guinea pig, respectively. When the inhaled dose was adjusted to reflect deposited dose, the rabbit animal model appears the most sensitive with the guinea pig the least sensitive species. 相似文献