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621.
622.
ABSTRACT: A macroscale hydrologic model is developed for regional climate assessment studies under way in the southeastern United States. The hydrologic modeling strategy is developed to optimize spatial representation of basin characteristics while maximizing computational efficiency. The model employs the “grouped response unit” methodology, which follows the natural drainage pattern of the area. First order streams are delineated and their surface characteristics are tested so that areas with statistically similar characteristics can be combined into larger computational zones for modeling purposes. Hydrologic response units (HRU) are identified within the modeling units and a simple three‐layer water balance model, Soil and Water Assessment Tool (SWAT), is executed for each HRU. The runoff values are then convoluted using a triangular unit hydrograph and routed by Muskingum‐Cunge method. The methodology is shown to produce accurate results relative to other studies, when compared to observations. The model is used to evaluate the potential error in hydrologic assessments when using GCM predictions as climatic input in a rainfall‐runoff dominated environment. In such areas, the results from this study, although limited in temporal and spatial scope, appear to imply that use of GCM climate predictions in short term quantitative analyses studies in rainfall‐runoff dominated environments should proceed with caution.  相似文献   
623.
The article presents household vulnerability, local community adaptive capacity, and government’s response to tidal flood hazard in the Semarang coastal area, Central Java Province, Indonesia. Using data gathered from a survey of households, the study revealed a number of important factors about the interaction between people and flood. The coastal community has been experiencing problems related to tidal floods. They have adapted to tidal flooding with structural measures, such as increasing the floor level, making small dams in front of houses, increasing yard and street levels in the neighborhood area, and creating dykes around residential areas. Tidal flood mitigation in the Semarang coastal area should incorporate governmental action and local community capacities for proper protection of the population.  相似文献   
624.
《Environmental Hazards》2013,12(3):194-212
Emergency management tends to be planned for legal, resident populations that are responsive to mainstream channels of communication and enforcement. For many areas prone to extreme events and emergencies, populations are also composed of transitory tourists, temporary visitors and migrant workers. This latter group may be a large population and, while not completely invisible to residents, may prefer obscurity and concealment within the social landscape. Tending towards poverty, technologically disconnected and linguistically isolated, undocumented migrants seek employment and attempt to avoid local law enforcement and immigration officials for fear of imprisonment and deportation. In this context, the behaviours prompted by developing public emergencies will be different for undocumented migrants than for the population at large. We examine the experience of 135 Hispanic undocumented migrants in the coastal zone of Houston-Galveston, Texas to understand the factors and issues that influence decision making and behaviours under region-wide mandatory evacuation conditions. Undocumented migrants’ decisions to evacuate rest upon: the presence (or absence) of family and/or children, their access to risk information that they find meaningful and rational and is in harmony with their pre-conceptions about their circumstances, their openness to information that either confirms their experiences or confronts rumour-generated biases they carry, their familiarity with social groups and governmental agencies and the services they offer, and the outcome of their risk analyses that consider the dangers of remaining in situ against the danger of exposing themselves to discovery as ‘illegal aliens’. The results suggest that emergency management plans ought to promote the dispelling of rumours that weaken the effect of emergency communication, promote non-emergency outreach to peripheral populations through community groups, and promote better, basic, non-technical, Spanish-language media through mainstream conduits (i.e. the most commonly watched non-Spanish television channels) that do not require high-tech devices or advanced understanding of visual media tools.  相似文献   
625.
This paper deals with the applicability of seismic passive control in major-hazard chemical installations. The objective is to show numerically and experimentally the applicability of Passive Control Techniques (PCT) in industrial plants. Consequently, the main components of a process plant are classified and collected into a limited number of classes; for each class, the main damages caused by past earthquakes are described and the most vulnerable components are identified. A synthesis of the effects of earthquakes on the different typologies of process components is also presented and the most suitable innovative seismic protection systems, in particular passive control techniques (PCT), are acknowledged. Finally, the effectiveness of PCT in reducing the seismic response of process plant components is proved by three representative case studies: a base isolated above-ground storage tank, a distillation column connected by elastoplastic dampers to the adjacent service frame and an application of non-conventional Tuned Mass Dampers to a support frame.  相似文献   
626.
为通过计算机技术低成本的、高效的、准确的解决建筑火灾安全问题,对计算机技术在建筑结构火灾安全上的综合应用进行研究,并以某一小学教学楼为例将应用成果进行展示。首先,通过FDS软件对该建筑某火灾场景进行了火场数值模拟。基于FDS的数据,利用RCFire程序进行了结构构件内部温度计算和结构火灾反应计算。最后,在Vega的虚拟现实平台上将构件内部温度和结构火灾反应的结果进行了动态图形展示,并实现了结构火灾反应的同步漫游。本文将建筑火场模拟技术、结构火灾反应计算技术和场景表现技术上综合应用到同一建筑上,形成了一个更为准确的结构火灾反应模拟系统,同时也为进一步的建筑火灾场景仿真奠定了基础。  相似文献   
627.
Abstract: Hundreds of epiphytic bromeliads species are harvested from the wild for trade and for cultural uses, but little is known about the effects of this harvest. We assessed the potential demographic effects of harvesting from the wild on 2 epiphytic bromeliads: Tillandsia macdougallii, an atmospheric bromeliad (adsorbs water and nutrients directly from the atmosphere), and T. violaceae, a tank bromeliad (accumulates water and organic material between its leaves). We also examined an alternative to harvesting bromeliads from trees—the collection of fallen bromeliads from the forest floor. We censused populations of T. macdougallii each year from 2005 to 2010 and of T. violaceae from 2005 to 2008, in Oaxaca, Mexico. We also measured monthly fall rates of bromeliads over 1 year and monitored the survival of fallen bromeliads on the forest floor. The tank bromeliad had significantly higher rates of survival, reproduction, and stochastic population growth rates (λs) than the atmospheric bromeliad, but λs for both species were <1, which suggests that the populations will decline even without harvest. Elasticity patterns differed between species, but in both, survival of large individuals had high elasticity values. No fallen bromeliads survived more than 1.5 years on the forest floor and the rate of bromeliad fall was comparable to current harvest rates. Low rates of population growth recorded for the species we studied and other epiphytic bromeliads and high elasticity values for the vital rates that were most affected by harvest suggest that commercial harvesting in the wild of these species is not sustainable. We propose the collection of fallen bromeliads as an ecologically and, potentially, economically viable alternative.  相似文献   
628.
The main objective of this article is to determine key factors that may have a significant effect on the verbal abuse, emotional abuse and physical assault of health care workers in north-eastern Turkey. A self-administered survey was completed by 450 health care workers in three well-established hospitals in Erzurum, Turkey. Because of the discrete and ordered nature of the dependent variable of the survey, the data were analysed using four distinctive ordered response models. Results revealed that several key variables were found to be a significant determinant of workplace violence, such as the type of health institution, occupational position, weekly working hours, weekly shift hours, number of daily patient contacts, age group of the respondents, experience in the health sector, training against workplace violence and current policies of the hospitals and the Turkish Ministry of Health.  相似文献   
629.
This study sought to determine if spatiotemporal skills, represented by success in high level sport, transfer to driving and, if so, whether such transfer is mediated by the gender of the driver. Using an emergency-braking test, we compared the driving ability of male and female athletes and non-athletes and showed that athletes achieved significantly longer and therefore superior durations for time-to-contact. The advantage of athletic participation thus did not appear in movement time but rather in the ability to produce desirable performance in context. We found that males and females did not differ significantly with respect to driving, however, involvement in sport apparently transfers to aspects of driving and so provides benefits beyond the intrinsic reward of the sports activities themselves.  相似文献   
630.
近些年,境外中资企业员工遭遇武装袭击、绑架劫持事件屡有发生,如何加强境外公共安全管理,有效保障企业员工生命和设备财产安全成为了所有走向海外企业必须面对的一道严峻课题.以2012年3月26日中资公司施工队应对北南苏丹边界1/2/4油区爆发的军事冲突事件为例,详细描述了该中资公司队伍紧急避险和快速撤离的过程,对应急行动成功的经验进行了分析和总结,并进一步提出做好境外公共安全管理工作的重点.案例不但为境外中资企业应对和处置境外公共安全突发事件提供了样板,更为广大境外中资企业强化境外公共安全管理提供了借鉴和参考.  相似文献   
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