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851.
To save lives immediately after a catastrophic earthquake occurs, it is essential for an urban transportation system to retain
its functional performance in order to carry injured people to hospitals. Recent seismic assessment studies have mostly been
based on cost-benefit analyses, carried out in monetary terms that are reasonable for long-term considerations. However, many
problems of seismic risk management still remain. For example, attributing a monetary value to a human life is considered
impossible. Also, requirements for functioning of a transportation system are different in the period immediately after an
earthquake. This paper concentrates on how to assess the importance of an urban transportation system as it relates to saving
human life, and what system enhancements should be made to improve performance.
This paper proposes a risk assessment method for the functional reliability of a transportation system immediately after an
earthquake. In that period, system malfunction adversely affects the saving of lives as a result of time delays when moving
injured people to medical facilities. A system dynamics simulation of transporting injured people is incorporated in the method,
which uses two assessment approaches to evaluate the differences of cumulative injured people who receive medical care. In
deciding on the destination of medical facility in the simulation, two ways of deciding are addressed; one uses information
only on the road network, and the other uses information on both road network and hospital availability. Results of an application
to an actual target area show the most vulnerable road links and differences of the two decision-making processes. A way to
mitigate the loss due to damage to road links is examined. The paper also summarizes future developments in advanced information
technology for emergency transportation systems. 相似文献
852.
Environmental justice laws protect certain populations against discriminatory actions that may result from a myriad of enterprises, including transportation activities. Previous environmental equity studies examining the effects of transportation‐engendered externalities have been criticized on several points, including (1) that the choice of a reference population for comparison to the criterion variable may influence the outcome of research results and (2) that the selection and use of inappropriate methodologies intended to identify and characterize populations may foreordain research outcomes. This article examines the potentially confounding effects of selected spatial scale and population assignment strategies as applied to a study of excessive noise levels at a large Midwestern airport, finding that reported outcomes can vary significantly as a function of methodological choices. 相似文献
853.
Accessibility and land-use patterns at the forest fringe in the northeastern part of the Philippines 总被引:8,自引:0,他引:8
Accessibility is considered to be one of the most important determinants of use and land-cover change. In rural land-use change studies, the accessibility situation is often described by simple measures of the distance to a location of interest. In this paper, different measures of access are tested for a rural area at the forest fringe in the northeastern Philippines. The accessibility measures addressed range from simple distance measures to land-use type specific transport costs and a population potential measure. The different measures are tested based on their capacity to explain the spatial pattern of different land-use types. A comparison of the findings based on a spatial analysis and an analysis of household level data is made. It is concluded that the relation between land use and accessibility is dependent on the specific characteristics of the different land-use types. The (dis-)advantages of the use of the different accessibility measures are discussed. 相似文献
854.
National carbon dioxide emissions: geography matters 总被引:1,自引:1,他引:1
Eric Neumayer 《Area》2004,36(1):33-40
This article examines the role of geographical factors as determinants of cross-country differences in per capita carbon dioxide emissions. Such differences have been explained by economists mostly in terms of per capita income. Geographical factors on the other hand have been neglected by economic analysis. We examine the effects of cold and hot climates, transportation requirements and the availability of renewable energy sources on emissions. We find that with the exception of cooling requirements as measured by hot climates, all these geographical factors are statistically significant determinants of emissions in accordance with our expectation. Furthermore, cold climates and the availability of renewable resources are also substantively important. 相似文献
855.
南极冰盖下流动水、活跃冰下湖的活动对冰动力学、接地线稳定性和冰盖物质平衡都有重要影响。本文结合ICESat和CryoSat-2测高卫星数据集,分别运用重复轨道法和差分DEM法,对Byrd冰川流域17个活跃冰下湖进行长达16年的监测,并计算其平均高程和平均水量变化,总结活跃冰下湖的水文特征。根据水势方程获取了此区域的冰下排水路径图,结合冰下湖的位置和活动情况分析其相互间的水文联系。结果表明Byrd冰川流域多个活跃冰下湖间存在明显的水文联系:Byrd1和Byrd2冰下湖具有以2~3年为周期的储排水活动规律,并且Byrd1冰下湖主要受到上游Byrd2冰下湖活动的影响;Byrds9和Byrds14分别受到上游Byrds11和Byrds15冰下湖排水的补充,使湖水水量持续上升。 相似文献
856.
基于1979—2008年NCEP/CFSR再分析耦合数据集,研究了冬季MJO对ENSO事件的影响。结果表明,在年际时间尺度以及长期的年代际时间尺度上,热带印度洋MJO活动的强弱性都可以影响热带中东太平洋ENSO事件的发生和发展。在年际时间尺度上,ENSO发生前期征兆的赤道中东太平洋的西风爆发事件(Westerly Wind Burst,WWB),作为MJO影响ENSO的主要途径,存在着显著的次季节时间尺度的变化。相对于气候平均的赤道太平洋西部暖池区上升而东部下沉的Walker环流,MJO正位相东传后的西风异常,减弱了低层东风和赤道东太平洋海水上翻。这一上升海流的减弱导致了中东赤道太平洋的海温升高,从而有利于ENSO暖海温事件的发生。而在年代际时间尺度上,MJO范围和强度在1998年前后出现了明显的转变,1998年之前MJO的东移范围更东,强度更强,从而导致了西太平洋西风爆发区的次季节西风异常事件更加显著,在Bjeknes正反馈机制下对应了年代际时间尺度下的强尼诺事件出现,1998年之后则与之相反。冬季MJO对ENSO影响的这一年代际特征主要体现在晚冬季节,而在早冬伴随着印度洋的增暖,MJO强度一直在逐年增加。 相似文献
857.
忠县地面石质文物风化病害形式有:裂隙状风化、页片状风化、絮粉状风化、松胀状风化。其中以絮粉状风化对文物破坏最为严重。控制风化的主要因素是:岩性和岩体结构、气候和气象条件、人为的污染。现场简易强度测试数据表明,风化石材的力学强度明显下降。最后提出了三峡水库蓄水前,对石质文物搬迁和保护的建议。参加研究工作的还有王金华、陈超平、唐毅烈、邓修甫、卞大巍、黄明元等人。表13处文物概况Table1SurveyofthethreestoneculturalrelicsinZhongxianCounty表2石材的化学成分(%)Table2Chemicalcompositionsofrockmaterials注:丁房阙石样已非新鲜岩石。表3石材岩块的主要物理力学性质指标Table3Mainphysical-mechanicalparametersofrockmaterials注:灰绿色砂岩试验成果取自三峡工程库区环境地质研究有关资料。2石质文物的风化病害分析受自然地质环境及人文环境的制约,3处石质文物的主要环境病害是风化病害。2.1风化病害形式[1](1)裂隙状风化。这是一种典型的物理风化形式,见于无铭阙和临江岩摩崖造像。无 相似文献
858.
859.
Yang Wuyang 《地理学报(英文版)》1995,(3)
Behing(N0rthCapital)issituatedatthenoItl1emextren1ityoftheNortl1ChinaPlainandl40kintoitssoutheaststretcllesh1eB0haiSea,aninlandseaofPacific.ItisshLifinbymoUntainsonthenortheast,nortl1andwest.Threerivers0fYongding,WenyuandChaobaiflowacrossh1ecounrysidetoth… 相似文献
860.
论经济地理研究中的运输化问题 总被引:1,自引:0,他引:1
本文提出运输化是工业化的重要特征,也是伴随工业化而发生的一种经济过程,经济发展的运输化过程受一定客观规律的支配。应当重视运输化进程与生产力布局、经济空间结构改善之间的关系,把对不同区域运输化发展水平及运输化进一步走向的分析,与经济发展规划结合起来。 相似文献