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921.
922.
Marine intertidal organisms in Prince William Sound were exposed to crude oil following the T/V Exxon Valdez oil spill in 1989. The intertidal communities were also subjected to mechanical disturbance during invasive oil spill remediation and cleanup efforts. Using monitoring data collected from 1989 to 1997, impacts and eventual recovery were assessed at oiled but uncleaned sites and oiled and cleaned study areas. A statistical model where recovery was defined as parallelism between the time profiles at control and oiled sites was evaluated. Statistical analysis and graphical presentations of the data suggest intertidal epibiota communities recovered from the oil spill by 1992 at the oiled sites and by 1994 at the oiled and remediated sites. Empirical data from the intertidal monitoring program supports the use of tests of parallelism in evaluating recovery and the need to avoid simply the comparison of sample means from control and oiled sites.  相似文献   
923.
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   
924.
小型油水分离器的设计及试验   总被引:2,自引:0,他引:2  
简要介绍了CYF-0.1/CYF-0.05型油水分离器的基本原理、主要参数、设计计算及台架试验情况。  相似文献   
925.
介绍了中国石油天然气集团公司 (CNPC)建立 HSE(健康、安全、环境 )管理体系的基本思路、现状和发展趋势。CNPC基于国际石油工业勘探和开发 (E& P)论坛 HSE指南及中华人民共和国石油和天然气工业行业标准《石油工业健康安全环境管理体系》(SY/ T62 76- 1 997)建立的HSE管理体系 ,有机的融入了 ISO90 0 0、ISO1 4 0 0 0 ,以及 OHS(职业安全卫生 )管理体系的内容 ,经过3年多的实践 ,在健康、安全与环境管理方面取得了显著的绩效  相似文献   
926.
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   
927.
The 2017 Ahmedpur Sharqia oil tanker explosion and fire, costing 219 lives, is one of the biggest ever road transportation disasters in history. This paper presents a detailed investigation and analysis of the accident circumstances and the series of events that contributed to the calamity. The investigation follows a holistic approach that examines the whole system including driver management, vehicle design, road design, and police management of the spillage scene.The analysis shows that although the first cause was driver dozing off behind the wheel, it was a complete system failure which created a domino effect. If all safety systems were in place, there would have not been any serious consequences of that first error. The investigation revealed that there were serious lapses in the design and fabrication of the vessel and truck in violation of UN-ADR safety standards and Pakistan's OGRA-RT standards andno proper protocols or SOPs were followed for driver workload and shift management by Shell Pakistan Ltd. and its contractors. Mismanagement of the post crash scenario by local law enforcement agencies was also a major serial failure. The study provides crucial lessons on the domino nature of such disasters.  相似文献   
928.
《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   
929.
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   
930.
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   
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