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871.
城市灭火救援决策支持系统研究述评   总被引:1,自引:0,他引:1  
随着经济的发展和城市化进程的加速,城市火灾危险因素越来越多,火灾仍然是各种灾害中发生最频繁且具有很强破坏性的一种。充分利用现代化的技术手段,包括计算机技术、现代通信技术、管理信息系统技术、地理信息系统技术,建立基于GIS的消防决策支持系统,有效调度和科学利用消防减灾资源,这对于减少火灾造成的损失是十分必要的。本文对灭火救援决策支持系统的国内外研究和应用现状进行了综述和分析,分析了现有灭火救援决策系统存在的问题,并指出了消防灭火救援决策支持系统的发展趋势。  相似文献   
872.
In order to assess whether nitrogen (N) loads in mosses reflect different land uses, 143 sites in North Rhine-Westphalia, the Weser-Ems Region and the Euro Region Nissa were sampled between 2000 and 2005. The data were analysed statistically with available surface information on land use and forest conditions. N bioaccumulation in mosses in the Weser-Ems Region with high densities of agricultural land use and livestock exceeded the concentrations in the more industrialised Euro Region Nissa. In all three study areas agricultural and livestock spatial densities were found to be positively correlated with N bioaccumulation in mosses. In North Rhine-Westphalia, the N concentrations in mosses was also moderately correlated with N concentrations in leaves and needles of forest trees. The moss method proved useful to assess the spatial patterns of N bioaccumulation due to land use.  相似文献   
873.
Landfill siting is a difficult, complex, tedious, and protracted process requiring evaluation of many different criteria. This paper presents a fuzzy multicriteria decision analysis alongside with a geospatial analysis for the selection of landfill sites. It employs a two-stage analysis synergistically to form a spatial decision support system (SDSS) for waste management in a fast-growing urban region, south Texas. The first-stage analysis makes use of the thematic maps in Geographical information system (GIS) in conjunction with environmental, biophysical, ecological, and socioeconomic variables leading to support the second-stage analysis using the fuzzy multicriteria decision-making (FMCDM) as a tool. It differs from the conventional methods of integrating GIS with MCDM for landfill selection because the approach follows two sequential steps rather than a full-integrated scheme. The case study was made for the city of Harlingen in south Texas, which is rapidly evolving into a large urban area due to its vantage position near the US-Mexico borderlands. The purpose of GIS was to perform an initial screening process to eliminate unsuitable land followed by utilization of FMCDM method to identify the most suitable site using the information provided by the regional experts with reference to five chosen criteria. Research findings show that the proposed SDSS may aid in recognizing the pros and cons of potential areas for the localization of landfill sites in any study region. Based on initial GIS screening and final FMCDM assessment, "site 1" was selected as the most suitable site for the new landfill in the suburban area of the City of Harlingen. Sensitivity analysis was performed using Monte Carlo simulation where the decision weights associated with all criteria were varied to investigate their relative impacts on the rank ordering of the potential sites in the second stage. Despite variations of the decision weights within a range of 20%, it shows that "site 1" remains its comparative advantage in the final site selection process.  相似文献   
874.
This paper examines how multiple criteria analysis (MCA) can be used to support multi-stakeholder environmental management decisions. It presents a study through which 48 stakeholders from environmental, primary production and community interest groups used MCA to prioritise 30 environmental management problems in the Mackay-Whitsunday region of Queensland, Australia. The MCA model, with procedures for aggregating multi-stakeholder output, was used to inform a final decision on the priority of the region's environmental management problems. The result was used in the region's environmental management plan as required under Australia's Natural Heritage Trust programme. The study shows how relatively simple MCA methods can help stakeholders make group decisions, even when they hold strongly conflicting preferences.  相似文献   
875.
On-ground natural resource management actions such as revegetation and remnant vegetation management can simultaneously affect multiple objectives including land, water and biodiversity resources. Hence, planning for the sustainable management of natural resources requires consideration of these multiple objectives. However, planning the location of management actions in the landscape often treats these objectives individually to reduce the process and spatial complexity inherent in human-modified and natural landscapes. This can be inefficient and potentially counterproductive given the linkages and trade-offs involved. We develop and apply a systematic regional planning approach to identify geographic priorities for on-ground natural resource management actions that most cost-effectively meet multiple natural resource management objectives. Our systematic regional planning approach utilises integer programming within a structured multi-criteria decision analysis framework. Intelligent siting can capitalise on the multiple benefits of on-ground actions and achieve natural resource management objectives more efficiently. The focus of this study is the human-modified landscape of the River Murray, South Australia. However, the methodology and analyses presented here can be adapted to other regions requiring more efficient and integrated planning for the management of natural resources.  相似文献   
876.
This contribution discusses a site selection process for establishing a local park. It was supported by a value-focused approach and spatial multi-criteria evaluation techniques. A first set of spatial criteria was used to design a number of potential sites. Next, a new set of spatial and non-spatial criteria was employed, including the social functions and the financial costs, together with the degree of suitability for the park to evaluate the potential sites and to recommend the most acceptable one. The whole process was facilitated by a new software tool that supports spatial multiple criteria evaluation, or SMCE. The application of this tool, combined with a continual feedback by the public administration, has provided an effective methodology to solve complex decisional problem in land-use and urban planning.  相似文献   
877.
环境决策支持系统中两类模型方法的整合   总被引:2,自引:0,他引:2  
该文对环境决策支持系统中情景分析和数学优化两类模型方法的优缺点和适用范围进行了比较分析。实例研究表明,两类模型方法的整合使用可以有效地支持较为复杂的决策过程。   相似文献   
878.
Assessing and adapting to the impacts of climate change requires balancing social, economic, and environmental factors in the context of an ever-expanding range of objectives, uncertainties, and management options. The term decision support describes a diverse class of resources designed to help manage this complexity and assist decision makers in understanding impacts and evaluating management options. Most climate-related decision support resources implicitly assume that decision making is primarily limited by the quantity and quality of available information. However, a wide variety of evidence suggests that institutional, political, and communication processes are also integral to organizational decision making. Decision support resources designed to address these processes are underrepresented in existing tools. These persistent biases in the design and delivery of decision support may undermine efforts to move decision support from research to practice. The development of new approaches to decision support that consider a wider range of relevant issues is limited by the lack of information about the characteristics, context, and alternatives associated with climate-related decisions. We propose a new approach called a decision assessment and decision inventory that will provide systematic information describing the relevant attributes of climate-related decisions. This information can be used to improve the design of decision support resources, as well as to prioritize research and development investments. Application of this approach will help provide more effective decision support based on a balanced foundation of analytical tools, environmental data, and relevant information about decisions and decision makers.  相似文献   
879.
While deterministic forecasts provide a single realization of potential inundation, the inherent uncertainty associated with forecasts also needs to be conveyed for improved decision support. The objective of this study was to develop an ensemble framework for the quantification and visualization of uncertainty associated with flood inundation forecast maps. An 11‐member ensemble streamflow forecast at lead times from 0 to 48 hr was used to force two hydraulic models to produce a multimodel ensemble. The hydraulic models used are (1) the International River Interface Cooperative along with Flow and Sediment Transport with Morphological Evolution of Channels solver and (2) the two‐dimensional Hydrologic Engineering Center‐River Analysis System. Uncertainty was quantified and augmented onto flood inundation maps by calculating statistical spread among the ensemble members. For visualization, a series of probability flood maps conveying the uncertainty in forecasted water extent, water depth, and flow velocity was disseminated through a web‐based decision support tool. The results from this study offer a framework for quantifying and visualizing model uncertainty in forecasted flood inundation maps.  相似文献   
880.
小凌河矿回采巷道交叉点支护技术研究   总被引:2,自引:0,他引:2  
为了得出小凌河矿回采巷道交叉点处的支护方案,建立了FLAC3D数值模拟模型。针对南票煤电集团小凌河煤矿-580 m南翼溜煤道处于大倾角、受动载影响的地质条件,理论分析了交叉巷道围岩应力与变形特点,通过FLAC3D数值模拟与工程类比确定了联络巷支护方案。分析了巷道交叉点围岩应力分布和位移规律分布,确定了巷道交叉点处的补强支护方案,顶板采用钢筋托梁组合锚杆支护,并进行锚索补强。交叉的两条巷道在保持原有支护参数的基础上通过增加顶板锚索的根数来提高支护强度。结果表明,在顶板采用钢筋托梁组合锚杆支护和锚索补强,可有效控制围岩离层和结构面变形。数值模拟和传统方法相比,针对性强,更快捷方便。  相似文献   
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