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141.
This paper discusses the social science and engineering dimensions of search and rescue (SAR) in collapsed buildings. First, existing information is presented on factors that influence the behaviour of trapped victims, particularly human, physical, socioeconomic and circumstantial factors. Trapped victims are most often discussed in the context of structural collapse and injuries sustained. Most studies in this area focus on earthquakes as the type of disaster that produces the most extensive structural damage. Second, information is set out on the engineering aspects of urban search and rescue (USAR) in the United States, including the role of structural engineers in USAR operations, training and certification of structural specialists, and safety and general procedures. The use of computational simulation to link the engineering and social science aspects of USAR is discussed. This could supplement training of local SAR groups and USAR teams, allowing them to understand better the collapse process and how voids form in a rubble pile. A preliminary simulation tool developed for this purpose is described. 相似文献
142.
143.
Chrastansky A Callies U Fleet DM 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):194-198
Chronic oil pollution by illegal oil dumping in the North Sea is difficult to quantify. Beached, oil-contaminated sea birds, however, may be used as an indirect indicator. Reconstructing the drift of oil slicks and sea bird corpses in the southern North Sea for the period 1992-2003 by means of a two-dimensional numerical transport model driven by re-analysed weather data, we show with an example of two common sea bird species that the variability observed within the number of corpses registered during beached bird surveys for the German coast primarily reflects the inter-annual variability of prevailing weather conditions. This should be taken into account when interpreting the data. We propose normalisation of beached bird survey data based on numerical drift simulations to improve the recognition of trends in the level of chronic oil pollution. 相似文献
144.
145.
A preliminary investigation was performed to estimate the effect of the degree of treatment in Sewage Treatment Plants (STPs) on the status of pollution along the coastlines of the Mediterranean Sea. Data from questionnaires and the literature were collected and processed (a) to identify 18 approximate 1D surface coastal currents, (b) to estimate their prevailing direction and average flow velocity and (c) to estimate the water pollution loads and identify their locations of discharge. Then, a simplified 1D water quality model was formulated and applied for the existing conditions and two hypothetical scenarios: (1) all coastal cities have STPs with secondary treatment and (2) all coastal cities have STPs with tertiary treatment to determine BOD(5), TN and TP concentrations in the 18 surface coastal currents. Calculated concentrations were compared and discussed. A main conclusion is that, to reduce pollution in the Mediterranean Sea measures should be adopted for upgrading the water quality of the rivers discharging into the Mediterranean Sea, along with the construction of STPs for all the coastal cities. 相似文献
146.
Bioregional classifications are used extensively for conservation management and monitoring programs. This study used generalised dissimilarity modelling (GDM) to test the ability of different regional classifications of four groups of aquatic biota to be used as surrogates for each other. Classifications were derived for aquatic macrophytes, macroinvertebrates, freshwater fish and frogs using community-level modelling, or GDM, which relates the biotic assemblage structure with environmental variables. Six regions were defined for each biotic group for the State of New South Wales. Regional classifications differed markedly between the different biotic groups because the environmental drivers that were related to species turnover throughout the region differed among groups. Altitude and rainfall were the strongest drivers of species turnover among the groups. Results suggest that physiographic variables should be incorporated in reserve design and monitoring programs to explicitly address differences in classifications between similar biotic groups. 相似文献
147.
This study examines the impact of flooding on land of high conservation value located along part of the southern shoreline
of the River Clyde Estuary in western Scotland. This paper hypothesizes that, over the next 50 years, the frequency and extent
of coastal flooding will increase due to the gradual effect of global warming and the consequent rise in sea-level and increase
in storminess. It is argued that because of the great cost of constructing new flood defence systems it will not be possible
to protect all land areas to an equal extent from flooding. A means of ranking different land use will be necessary so that
society can make a rational judgement concerning which sections of coastline will be worth protecting. This study provides
a methodology that combines an objective ranking of conservation areas using non-economic indicators with a GIS model of flood
potential, and permits accurate forecasts of flood losses to conservation areas of different ecological value. The conservation
case study used in this paper proposes the use of an ecological weighting value based on five ecological variables each of
10 categories. Tables and maps identify the sites that have been highlighted as consisting of the most ‘valuable’ conservation
sites. The methodology makes extensive use of geographical information systems (GIS) to model the predicted areas of flooding
and to calculate conservation weighting values of the land areas. 相似文献
148.
This paper describes one example of how the UK National Air Quality Strategy (NAQS) is implemented in a local urban environment. The paper reviews the beginning of this process, by examining the review and assessment procedures of the NAQS in the London Borough of Barnet. By the application of available UK tools of local air quality management (LAQM), the process began through analysis of the levels of local emissions and progressed onto modelling of current and future air quality. A map showing combined emission hotspot areas for the Borough indicated and higher emission rates occur in the south of the Borough and along the major transport corridors, as road sources dominate emissions. Dispersion modelling studies were also conducted for this purpose, using the screening models GRAM, PGRAM and ADMS Urban for an in-depth assessment. These analyses found that some local point sources and the majority of Borough roads with over 20,000 vehicles per day produced exceedances of the future objectives for air quality for some pollutants.Recommendations for the progression of LAQM in the Borough are made and include the update and expansion of the emissions information held for use in future modelling studies. The paper demonstrates the experience of implementing the Strategy, using the tools and procedures available for this purpose, in a local urban environment that is similar to many in the UK. 相似文献
149.
An Integrated Approach Towards Assessing the Value of Water: A Case Study on the Zambezi Basin 总被引:1,自引:0,他引:1
The aim of this paper is to develop a methodology for assessing the value of water in the different stages in the water cycle.
It is hypothesised that if a cubic metre of water provides some benefit in some spot at a certain moment, this cubic metre
of water has a certain value not only at that point in space and time, but in its previous stages within the water cycle as
well. This means that, while water particles flow from upstream to downstream, water values ‘flow’ in exactly the opposite
direction. The value of water in a certain place is equal to its value in situ plus an accumulated value derived from downstream. This value-flow concept is elaborated for the Zambezi basin.
It is found that water produces the smallest direct economic benefits in the upper part of the Zambezi basin. However, water
flows in this part of the basin − due to their upstream location − have the highest indirect values. Return flows from the
water-using sectors are particularly valuable in the upstream sub-basins. The analysis shows that the value per unit of river
water increases if we go from downstream to upstream. Another finding of the study is that percolation of rainwater is generally
more valuable than surface runoff. Finally, a plan to export water from the river Zambezi to South Africa is evaluated in
terms of its opportunity costs.
The results of this study show that the value-flow concept offers the possibility of accounting for the cyclic nature of water
when estimating its value. It is stressed, however, that for the current study many crude assumptions had to be made, so that
the exact numbers presented should be regarded with extreme caution. Further research is necessary to provide more precise
and validated estimates.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
150.
Sanna Syri Antti Lehtil Tommi Ekholm Ilkka Savolainen Hannele Holttinen Esa Peltola 《International Journal of Greenhouse Gas Control》2008,2(2):274-285
The achievement possibilities of the EU 2 °C climate target have been assessed with the ETSAP TIAM global energy systems model. Cost-effective global and regional mitigation scenarios of carbon dioxide, methane, nitrous oxide and F-gases were calculated with alternative assumptions on emissions trading. In the mitigation scenarios, an 85% reduction in CO2 emissions is needed from the baseline, and very significant changes in the energy system towards emission-free sources take place during this century. The largest new technology groups are carbon-capture and storage (CCS), nuclear power, wind power, advanced bioenergy technologies and energy efficiency measures. CCS technologies contributed a 5.5-Pg CO2 annual emission reduction by 2050 and 12 Pg CO2 reduction by 2100. Also large-scale forestation measures were found cost-efficient. Forestation measures reached their maximum impact of 7.7 Pg CO2 annual emission reduction in 2080. The effects of uncertainties in the climate sensitivity have been analysed with stochastic scenarios. 相似文献