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Risk evaluation of Natural disasters based on connection function

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Chinese Journal of Population,Resources and Environment 2013年第2期11卷 118-124页

作者： Zhengwei Pan Juliang Jin Li Liu Xiaowei Liu School of Civil and Environmental Engineering Anhui Xinhua University School of Civil Engineering Hefei University of Technology School of Environment Beijing Normal University

There are many uncertain factors,such as stochastic,fuzzy and gray information in the risk analysis on Natural hazard.The set pair analysis(SPA)deals effectively with the various uncertain factors contributing to evaluation of the risk level of Natural disasters.The evaluation indicators and standards of Natural disasters risk are analyzed by identity-discrepancycontrary(IDC).The result,the connection numbers,still has uncertainty information.Thus,yielding the risk evaluation model of Natural disasters based on connection function,which construct a set pair relation between the indicators of connection numbers and comprehensive evaluation standards,and describe uncertainty of the connection numbers by using connection function.The study showed that the proposed model takes into account only the uncertainty of risk evaluation indicator identification on Natural disasters,also the uncertainty of result connection numbers.This approach gives full consideration to the uncertainty of systematic evaluation process along with the actual meaning of comprehensive evaluation functions.Therefore,this means it is able to reduce the uncertainty of final evaluation results and improve the accuracy and reasonability of evaluation results.This model is capable of reflecting actual situation of the risk evaluation on Natural disaster affected by various uncertain factors and has a promotional value in the Natural disaster risk assessment.

关键词： set pair analysis connection function Natural disaster risk level system comprehensive evaluation

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液化天然气池火固体火焰模型及预测工具

消防科学与技术 2015年第1期34卷 120-122页

作者：刘昌华党文义化学品安全控制国家重点实验室山东青岛266071 中国石油化工股份有限公司青岛安全工程研究院山东青岛266071

通过对陆上和水上LNG大尺寸火灾实验测试结果进行分析,得到影响LNG池火灾热辐射的关键参数,包括最大燃烧速率、最大表面热辐射能及LNG池火燃烧速率、表面热辐射能、火焰形状和传输率预测模型,并据此开发了基于固体火焰模型的LNG池火热... 详细信息

通过对陆上和水上LNG大尺寸火灾实验测试结果进行分析,得到影响LNG池火灾热辐射的关键参数,包括最大燃烧速率、最大表面热辐射能及LNG池火燃烧速率、表面热辐射能、火焰形状和传输率预测模型,并据此开发了基于固体火焰模型的LNG池火热辐射预测工具LNGFHR。与LNGFIRE 3模型的计算结果进行对比,表明LNGFHR在陆上圆形LNG池火灾热辐射预测值与LNGFIRE 3接近;对于水面LNG池火,LNGFHR采用了最新的大尺寸LNG水面池火实验的研究结果,其预测结果大于LNGFIRE 3模型的预测值。

关键词：液化天然气 LNG池火热辐射安全评估固体火焰模型 LNGFIRE 3 liquefied Natural gas (LNG) LNGFIRE 3

Spatial-temporal variations of Natural suitability of human settlement environment in the Three Gorges Reservoir Area A case study in Fengjie County,China

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Frontiers of Earth Science 2019年第1期13卷 1-17页

作者： Jieqiong LUO Tinggang ZHOU Peijun DU Zhigang XU Key Laboratory for Satellite Mapping Technology and Applications of State Administration of Surveying Mapping and Geoinformation of China Nanjing UniversityNanjing 210023China Jiangsu Provincial Key Labomtory of Geographic Information Science and Technology Nanjing UniversityNanjing 210023China Jiangsu Center for CoUabomtive Innovation in Geographical Information Resource Development and Application Nanjing 210023China School of Geographical Sciences Southwest UniversityChongqing 400715China Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education) Chongqing 400715China

With rapid environmental degeneration and socio-economie development,the human settlement environment (HSE)has experienced dramatic changes and attracted attention from different communities.Consequently,the spatial-temporal evaluation of Natural suitability of the human settlement environment (NSHSE)has become essential for understanding the patterns and dynamics of HSE,and for coordinating sustainable development among regional populations,resources,and environments.This study aims to explore the spatialtemporal evolution of NSHSE patterns in 1997,2005,and 2009 in Fengjie County near the Three Gorges Reservoir Area (TGRA).A spatially weighted NSHSE model was established by integrating multi-source data (e.g.,census data,meteorological data,remote sensing images,DEM data,and GIS data)into one framework,where the Ordinary Least Squares (OLS)linear regression model was applied to calculate the weights of indices in the NSHSE model.Results show that the trend of Natural suitability has been first downward and then upward, which is evidenced by the disparity of NSHSE existing in the south,north,and central areas of Fengjie County. Results also reveal clustered NSHSE patterns for all 30 townships.Meanwhile,NSHSE has significant influence on population distribution,and 71.49% of the total population is living in moderate and high suitable districts.

关键词： Natural suitability of human settlement environment ordinary least squares model global and local spatial autocorrelation analyses Three Gorges Reservoir Area (TGRA) Fengjie Cotmty

Virtual screening and optimization of typeⅡ inhibitors of JAK2 from a Natural product library

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中国药理学与毒理学杂志 2015年第S1期29卷 98-99页

作者： Dik-LungMA DanielShiu-HinCHAN GuoWEI Hai-jingZHONG HuiYANG LaiToLEUNG ElizabethA.GULLEN PaulineChIU Yung-ChiCHENG Chung-hangLEUNG Department of Chemistry Hong Kong Baptist University Hong Kong China Department of Chemistry and the State Key Laboratory of Synthetic Chemistry University of Hong Kong Hong Kong China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical Sciences University of Macao Macao China Department of Pharmacology Yale University School of Medicine New Haven CT 06520 USA

OBJECTIVE To utilize a structure-based lead optimization approach to generate novel Natural product-like typeⅡ inhibitors of JAK2 using the DOLPHIN protocol.METHODS Initially,the DOLHPIN computational protocol was employed to convert an active(DFG-in)conformation of JAK2 into a typeⅡ-compatible conformation,which was used as a model for the structure-based virtual screening of 150 000 Natural product-like compounds in silico.The novel biflavonoid analogues were designed and synthesized based on the structure of lead compound and then tested for JAK2 and STAT3 inhibitory activity,cytotoxicity and HCV antiviral activity.RESULTS The top eleven highest-scoring compounds were generated from the initial high-throughput virtual screening.Amentoflavone 1a,a biflavonoid from the Chinese plant Gingko biloba,emerged as a promising candidate for further biological evaluation.In dose-response experiments,amentoflavone 1ainhibited JAK2 activity in a concentration dependent fashion with an IC50 value of 5μmol·L-1.As a proof-of-concept,we designed nine analogues 1b-1j with the addition of one or more aliphatic side chains to the biflavonoid scaffold of 1a.The octyl(C8)analogue 1bdisplayed superior potency against JAK2 activity and HCV activity compared to the parent compound 1a,validating the structure-based lead optimization approach used in this study.Moreover,kinetic analysis indicated that analogue 1bexhibited a non-competitive mode of inhibition,suggesting that this compound may be a putative typeⅡ inhibitor of JAK2.CONCLUSION Amentoflavone 1ahas been identified as a JAK2 inhibitor by structure-based virtual screening of a Natural product library.In silico optimization using the DOLPHIN model yielded analogues with enhanced potency against JAK2 activity and HCV activity in cellulo.Molecular modeling and kinetic experiments suggested that the analogues may function as typeⅡ inhibitors of JAK2.

关键词： JAK2 Natural products virtual screening structure-

Changes of Population, Built-up Land, and Cropland Exposure to Natural Hazards in China from 1995 to 2015

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International Journal of Disaster Risk Science 2019年第4期10卷 557-572页

作者： Yimin Chen Wei Xie Xiaocong Xu School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China Guangdong Key Laboratory for Urbanization and Geosimulation Sun Yat-sen UniversityGuangzhou 510275China

By using the latest China population grid and land-use data,we assess the changing exposure of China’s population and land uses to the hazards of storm surges,droughts,earthquakes,floods,and landslides from 1995 to2015.We found that the single-hazard areas and the multihazard areas covered 43%and 26%of China’s territory,respectively.Population grew faster in the hazard-prone areas than in the non-hazard areas.Built-up area expanded more rapidly in the areas prone to earthquakes and landslides.Cropland changed rapidly in many hazard-prone areas.The hazard-prone areas affected by floods featured the highest cropland loss rates,while the areas prone to earthquakes and landslides featured the highest cropland growth rates.We detected areas with significant exposure changes by using hot spot analysis.It was found that population and built-up land in the Pearl River Basin were increasingly exposed to storm surges,floods,and landslides.The Haihe River Basin and Huaihe River Basin also showed a consistent increase of population and built-up land exposure to droughts and earthquakes.These findings can provide a foundation for the design and implementation of protection and adaptation strategies to improve the resilience of Chinese society to Natural hazards.

关键词： China Exposure to Natural hazards Population change Built-up land Cropland

Study on Laminar Natural Convection Heat Transfer from a Hemisphere with Uniform Heat Flux Surface

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Journal of Thermal Science 2019年第2期28卷 232-245页

作者： ZHANG Jian LIU Jie LU Wenqiang School of Engineering Science University of Chinese Academy of Sciences

By employing the modified model based on Bejan et al., laminar Natural convection heat transfer from a hemisphere with uniform heat flux surface has been numerically investigated. Extensive results of two different surface boundary conditions are obtained for a wide range of Grashof numbers(10 ≤ Gr ≤ 10~7) and Prandlt number of 0.72. The characteristics of heat transfer and fluid flow are analyzed in terms of isotherm contours and streamline patterns, radial and tangential velocities, dimensionless temperature profiles, local friction and pressure drag coefficients, as well as local and average Nusselt numbers. Meanwhile, the effects of Grashof number and adiabatic surface on flow motion and heat transfer have been studied. No recirculation zone or flow separation generates over the top of the hemisphere compared to the isothermal sphere. Owing to the curvature effect, the maximum values of local friction and pressure drag coefficients appear at the corner point B. Comparisons with the previous results are also reported in detail. All the results are in good agreement with the numerical data. Moreover, both local and average Nusselt numbers show a positive dependence on Grashof number. The values of the non-adiabatic case are smaller than that of the adiabatic case due to the preheating effect. Finally, two precise and general correlations of average Nusselt number varying with Grashof numbers have been presented, which can provide an effective prediction for the heat transfer rate in engineering applications, and offer academic values for the future research.

关键词： numerical simulation Natural convection hemisphere uniform heat flux heat transfer correlations

The Nature of “Natural Disasters”: Survivors’ Explanations of Earthquake Damage

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International Journal of Disaster Risk Science 2019年第3期10卷 293-305页

作者： Alessandro Massazza Chris R.Brewin Helene Joffe Department of Clinical Educational and Health PsychologyUniversity College London

The distinction between Natural and human-made disasters is ingrained in everyday language. Disaster scientists have long been critical of this dichotomy. Nonetheless,virtually no attention has been paid to how disaster survivors conceptualize the causes of the disasters they experience. In this mixed-methods longitudinal study, 112 survivors of the2016–2017 Central Italy earthquakes completed questionnaires 3 and 16 months following the earthquakes, with the aim of assessing attributions of blame for the earthquake damage. In-depth interviews were also conducted with 52 participants at the 3-month mark to explore representations of causation for the earthquake damage. The distinction between disasters caused by nature and disasters caused by humans was not supported by survivors of the earthquake. In the longitudinal surveys, building firms and the State were assigned as much blame as nature for the earthquake damage, at both 3 months and 16 months after the earthquakes.Corroborating this complexity, in the interviews, the causes of the earthquake damage, rather than being understood as purely Natural, were perceived as a complex mosaic composed of political, technological, Natural, and moral factors.This empirical work shows that disaster survivors combine both nature-based and human-based explanations of disasters, rather than subscribing to one or the other. These findings have practical implications for disaster risk reduction and response.

关键词： Amatrice Attributions Disaster causes Disaster survivors Human-made disasters Natural disasters 2016–2017 Central Italy earthquakes

An Analysis of Social Vulnerability to Natural Hazards in Nepal Using a Modified Social Vulnerability Index

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International Journal of Disaster Risk Science 2019年第1期10卷 103-116页

作者： Sanam K.Aksha Luke Juran Lynn M.Resler Yang Zhang Department of Geography Virginia Tech Virginia Water Resources Research Center Virginia Tech Urban Affairs and Planning Virginia Tech

Social vulnerability influences the ability to prepare for, respond to, and recover from disasters. The identification of vulnerable populations and factors that contribute to their vulnerability are crucial for effective disaster risk reduction. Nepal exhibits multihazard risk and has experienced socioeconomic and political upheaval in recent decades, further increasing susceptibility to hazards.However, we still know little regarding social vulnerability in Nepal. Here, we investigate social vulnerability in Nepal by adapting Social Vulnerability Index(SoVI) methods to the Nepali context. Variables such as caste, and populations who cannot speak/understand Nepali were added to reflect the essence of the Nepali context. Using principal component analysis, 39 variables were reduced to seven factors that explained 63.02% of variance in the data.Factor scores were summarized to calculate final SoVI scores. The highest levels of social vulnerability are concentrated in the central and western Mountain, western Hill, and central and eastern Tarai regions of Nepal, while the least vulnerable areas are in the central and eastern Hill regions. These findings, supplemented with smaller-scale analyses, have the potential to assist village officers, policymakers,and emergency managers in the development of more effective and geographically targeted disaster management programs.

关键词： Disaster risk reduction Natural hazards Nepal Principal component analysis Social Vulnerability Index

Phase-field-lattice Boltzmann simulation of dendrite growth under Natural convection in multicomponent superalloy solidification

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Rare Metals 2020年第2期39卷 147-155页

作者： Cong Yang Qing-Yan Xu Bai-Cheng Liu Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The thermosolutal convection can alter segregation pattern,change dendrite morphology and even cause freckles formation in alloy solidification.In this work,the multiphase-field model was coupled with lattice Boltzmann method to simulate the dendrite growth under melt convection in superalloy solidification.In the isothermal solidification simulations,zero and normal gravitational accelerations were applied to investigate the effects of gravity on the dendrite morphology and the magnitude of melt flow.The solute distribution of each alloy component along with the dendrite tip velocity during solidification was obtained,and the Natural convection has been confirmed to affect the microsegregation pattern and the dendrite growth velocity.In the directional solidification simulations,two typical temperature gradients were applied,and the dendrite morphology and fluid velocity in the mushy zone during solidification were analyzed.It is found that the freckles will form when the average fluid velocity in the mushy zone exceeds the withdraw velocity.

关键词： Dendrite growth Natural convection Phasefield model Lattice Boltzmann method