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61.
Despite overwhelming scientific consensus, millions of Americans fail to view climate change as a pressing threat. How can we address this disconnect between science and public opinion? In the present study, we investigated the role of metaphorical framing in shaping attitudes toward climate change. Participants read a brief article that metaphorically described US efforts to reduce carbon emissions as a war or race against climate change, or non-metaphorically described it as the issue of climate change. We further manipulated whether these emission-reduction goals emphasized the relatively near or distant future. We found that, compared to the race frame, the war metaphor made people perceive more urgency and risk surrounding climate change and express a greater willingness to increase conservation behavior, irrespective of the time horizon. Those who read the non-metaphorical report tended to respond in between these two extremes. We discuss the implications of these findings for climate communications.  相似文献   
62.
通过设计出的评价指数表 ,运用模糊综合评判原理 ,建立城市生活垃圾处理工程模式的逻辑推理数学模型 ,并利用Delphi6 .0高级编程语言研制出工程模式模糊综合评判系统 ,以确定可选择的城市生活垃圾处理工程模式  相似文献   
63.
城市火灾案例库辅助决策方法的研究   总被引:6,自引:1,他引:5  
在对城市火灾事故案例进行全面调查、统计和分类分析的基础上,提出一种城市火灾案例特征属性的表示框架,对特征属性进行了层次化和结构化,同时对属性值的取值进行较为科学而严格的定义,进而应用混合相似度度量方法和粗糙-模糊集方法提炼案例中蕴涵的灭火救援知识,给出一种灭火救援辅助决策过程模型;通过查找最相似案例和案例库提炼出相关的灭火救援规则进行灭火救援辅助决策;成功进行了实例验证。该模型的建立可为城市火灾案例智能决策系统的研究提供参考。  相似文献   
64.
吉林省松花江中下游污染物排放总量控制   总被引:1,自引:0,他引:1  
分析了实施总量控制的理论依据 ;并以此研究吉林省松花江中下游污染物总量控制以及吉林市控制单元的总量控制方案 ;最后探讨了总量控制措施。  相似文献   
65.
66.
简要论述了国内外防震减灾信息和辅助决策系统的发展状况。以大庆油田防震减灾信息和辅助决策系统为基础,详细探讨了分布式防震减灾系统的框架研究,包括ArcIMS的应用、系统框架的二次开发、数据库的远程连接和调用和系统框架的集成等。同时阐述了分布式网络GIS已经成为防震减灾信息和辅助决策系统建设的一个重要发展方向和它的应用价值。  相似文献   
67.
Abstract: A primary water quality problem caused by non-point source pollution (NPSP) is eutrophication, from excess nutrients in receiving water bodies. The control of nutrients arising from NPSP is difficult because the source areas can be hard to identify and typical treatment methods are infeasible due to the distributed nature of the pollutants. It may be possible to reduce nutrient related water quality problems through the restoration of highly disturbed watersheds with best management practices (BMPs). While restoration attempts may provide significant returns, they can be costly to implement and often are met with resistance in agricultural communities. Extending model results beyond the range of calibration to model future conditions such as for restoration scenarios requires the use of physically-based models that include the important processes that generate streamflow and material transport, uptake, loss, transformation, and recycling of nutrients and other material. The research and development objectives of the US. Army Engineer Research and Development Center (ERDC) in Vicksburg, Mississippi, are to develop a watershed assessment and management model to simulate transport, uptake, loss, transformation, and recycling of nutrients such as nitrogen and phosphorus and associated material such as sediment and organic matter. In this study we will discuss current efforts at the ERDC's Environmental Laboratory to develop a state-of-the-art watershed water quality model.  相似文献   
68.
The paper presents a novel transdisciplinary approach to investigate non-sustainable civilisation–nature interactions in the context of global change. The approach rests on the decomposition of intricate dynamics of Global Change into problematic patterns civilisation nature interactions (‘syndromes’) this is done by an iterative process of observations, data and theoretical system analysis and GIS-based modelling attempts. These syndromes of global change characterise endangering and risky developments of civilisation nature interaction and represent a baseline for measuring and indicating ‘non-sustainability’; in order to have a sustainable development it is necessary to have a far-reaching absence of syndromes. They encompass the core problems of global change, e.g. soil degradation, climate change, threats to biodiversity or global deforestation. Patterns are defined as characteristic constellations of global change trends (‘symptoms’). Cause–effect schemes of symptoms and their interrelations are constituted as complex phenomena resulting from interactions over the different spheres of the Earth system (biosphere, atmosphere, hydrosphere, population, pedosphere, economy, psychosocial sphere, social organisation, science and technology). The approach is illustrated by an analysis of civilisation–nature interaction patterns relevant for global deforestation. Global forest ecosystems have been chosen for this investigation because of their important role in the global carbon cycle and their importance for biological diversity. The resulting geographical patchwork of the combined dispositions and intensities of the different syndromes describes current and future regional threats to forests by their underlying global cause–effect patterns of civilisation–nature interaction.  相似文献   
69.
ABSTRACT: The NRCS curve number approach to runoff estimation has traditionally been to average or “lump” spatial variability into a single number for purposes of expediency and simplicity in calculations. In contrast, the weighted runoff curve number approach, which handles each individual pixel within the watershed separately, tends to result in larger estimates of runoff than the lumped approach. This work proposes further enhancements that consider not only spatial variability, but also the orientation of this variability with respect to the flow aggregation pattern of the drainage network. Results show that the proposed enhancements lead to much reduced estimates of runoff production. A revised model that considers overland flow lengths, consistent with existing NRCS concepts is proposed, which leads to only mildly reduced runoff estimates. Although more physically‐based, this revised model, which accounts directly for spatially distributed curve numbers and flow aggregation, leads to essentially the same results as the original, lumped runoff model when applied to three study watersheds. Philosophical issues and implications concerning the appropriateness of attempting to disaggregate lumped models are discussed.  相似文献   
70.
人类活动影响下的黄河流域水资源演化规律初探   总被引:12,自引:2,他引:10  
应用分布式流域水文模型WEP-L模型初步分析了人类活动影响下的黄河水资源演化规律。通过2000年现状下垫面条件下的评价结果与历史系列条件下的评价结果比较,以及考虑与不考虑人工取用水条件下的模拟结果比较,初步发现:黄河流域在强烈的人类活动影响下,水资源量及其构成均发生了显著变化,地表水资源量衰减,而不重复地下水量增加;在狭义水资源衰减的同时,伴随着有效蒸散即降水有效利用的增加,流域广义水资源量有一定幅度增加。研究成果对黄河的治理规划和水安全战略具有参考价值。  相似文献   
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