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991.
Two spatial optimization approaches, developed from the opposing perspectives of ecological economics and landscape planning and aimed at the definition of new distributions of farming systems and of land use elements, are compared and integrated into a general framework. The first approach, applied to a small river catchment in southwestern France, uses SWAT (Soil and Water Assessment Tool) and a weighted goal programming model in combination with a geographical information system (GIS) for the determination of optimal farming system patterns, based on selected objective functions to minimize deviations from the goals of reducing nitrogen and maintaining income. The second approach, demonstrated in a suburban landscape near Leipzig, Germany, defines a GIS-based predictive habitat model for the search of unfragmented regions suitable for hare populations (Lepus europaeus), followed by compromise optimization with the aim of planning a new habitat structure distribution for the hare. The multifunctional problem is solved by the integration of the three landscape functions (“production of cereals,” “resistance to soil erosion by water,” and “landscape water retention”). Through the comparison, we propose a framework for the definition of optimal land use patterns based on optimization techniques. The framework includes the main aspects to solve land use distribution problems with the aim of finding the optimal or best land use decisions. It integrates indicators, goals of spatial developments and stakeholders, including weighting, and model tools for the prediction of objective functions and risk assessments. Methodological limits of the uncertainty of data and model outcomes are stressed. The framework clarifies the use of optimization techniques in spatial planning.  相似文献   
992.
在分析应急预案内容及应急决策特点的基础上,针对应急决策中许多信息无法定量描述的问题,运用模糊集合理论,建立了在事故灾难复杂环境下对应急决策进行动态调整的模糊群体决策方法。该方法包括构造模糊偏好关系、设计备选方案选择的多属性群体决策模型和群体决策一致性的检验标准等内容,可以辅助应急决策者选择最佳决策方案。通过实证表明,该计算方法及实用效果,为突发事故应急预案的制订和事故现场的应急决策提供参考。  相似文献   
993.
论安全科学的若干基本规律与概念   总被引:1,自引:1,他引:0  
对安全问题所涉及客观事物的安全规律性进行了论述。在强调划分"受损事物"和"致损事物"之意义的基础上,给出判断某事物属于"安全"概念范畴的"受损事物"所应满足的4个安全特性,以及判断某事物属于"安全性"概念范畴的"致损事物"所应满足的3个安全特性。这些安全特性构成了安全科学的基本规律。对安全科学的重要概念"风险"和"危险"进行讨论,澄清了模糊认识。指出"风险"概念与受损事物相关,"危险"概念与致损事物相关,并分别给出二者的定义。两个概念不仅适用对象和定义不同,而且安全规律不同,计算方法亦不同,给出了二者的理论计算公式。  相似文献   
994.
“安全科学技术”一级学科修订   总被引:4,自引:2,他引:2  
介绍《学科分类与代码》国家标准中"安全科学技术"一级学科经过5年完成了制定,简述颁布16年后的实施及实践活动。近3年,经过多方研讨、论证,于2009年5月完成了"安全科学技术"一级学科的修订工作。通过该学科重新修订,进一步理顺了下属学科的名称、层次和隶属关系,增设多个(包括公共安全)二级学科和三级学科,使学科内容更加丰富、系统和完整。《学科分类与代码》国家标准GB/T13745—2009(代替GB/T13745—1992)的颁布实施,使"安全科学技术"一级学科在我国科教界的地位进一步巩固、发展和完善。  相似文献   
995.
对早期火灾信息进行研究,提出了一种基于非线性决策树的支持向量机多类分类模型。该模型利用非线性映射将样本投影到高维特征空间,比较每类样本在高维空间的分布情况,进行聚类构造出一个二叉决策树,使容易区分的类别从根节点逐层分类出来,有效克服了错分积累和避免不可分情况;同时,各个节点采用二值最小二乘小波支持向量机,以获得较高的泛化能力。该文将该模型用于早期火灾分类,并与BP神经网络、K近邻法和决策树方法进行比较,实验结果表明,该模型对早期火灾的识别率更高。  相似文献   
996.
Sustainable development, a concept which has been built with the sustainability of economic progression as a main thrust, has been a widely preferred model to traditional developmental models. However, the real meaning of what sustainable development is and should include has been an object of debate. On the one hand, differing from traditional economic developmental models, economic progress does not necessitate the practice of ‘sustainable development'. On the other hand, current levels of science and technology are still unable to solve several problems that arise with economic development. Sustainable development has transferred the responsibility of environmental destruction to that of developing countries. Lastly, instead of utilizing the best technology and leadership into formulating excellent environmental-protection policies, it is more important to create widespread awareness to the public on the need to protect the environment and thereby engage their participation in decision-making to actually realize what is truly ‘sustainable development'.  相似文献   
997.
This paper develops a conceptual model to examine the vulnerability of Inuit food systems to food insecurity as a consequence of climate change. The model illustrates that food system vulnerability is determined by the exposure and sensitivity of the food system to climate-related risks and its adaptive capacity to deal with those risks. The model is empirically applied using a case study from Igloolik, Nunavut. Specifically, the paper focuses on how extreme climate-related conditions in 2006 interacted with the food system to affect food security, using 2006 as a lens to identify and characterize some of the processes and conditions shaping vulnerability, and establishing a baseline for identifying and characterizing processes that are likely to shape future vulnerability. There is a high level of adaptive capacity among Igloolik Inuit, with food sharing mechanisms, hunting flexibility, and store-food access moderating the impact of climatic-risks on food security. However, high fuel and commodity prices, the increasing economic burden of adapting to back-to-back years with unfavorable climatic conditions, underlying community vulnerabilities, and the nature to the climate extremes in 2006, overwhelmed the adaptive capacity of many community members. Those dependent on traditional foods and having limited access to financial resources were particularly vulnerable.  相似文献   
998.
环境税是解决当前日趋严重的环境与经济发展冲突问题的有效手段之一,研究其如何影响投资者进入与退出项目的竞争策略是更好地制定环境税收政策的前提。与现有文献不同,本文应用期权博弈理论,构建煤电项目双寡头期权博弈模型,分进入和退出两种情况分析项目最优转换策略,并且定量分析环境税税率对最优转换临界值的影响。结果表明:环境税税率与最优转换临界值呈正比关系,即环境税率越低,项目越容易进入,并且更加难以退出;当存在竞争威胁时,投资者会加速进入与退出项目,当环境税强度逐渐变大时,将超过项目相互竞争的影响并起主要作用;在进入情况时存在等待、抢先进入和同时进入均衡,在退出情况时存在不退出、抢先退出和同时退出均衡,最后,分别给出各个均衡条件下环境税政策及影响,为政府制定环境税政策提供一种分析思路。  相似文献   
999.
Despite compelling reasons to involve nonscientists in the production of ecological knowledge, cultural and institutional factors often dis-incentivize engagement between scientists and nonscientists. This paper details our efforts to develop a biweekly newspaper column to increase communication between ecological scientists, social scientists, and the communities within which they work. Addressing community-generated topics and written by a collective of social and natural scientists, the column is meant to foster public dialog about socio-environmental issues and to lay the groundwork for the coproduction of environmental knowledge. Our collective approach to writing addresses some major barriers to public engagement by scientists, but the need to insert ourselves as intermediaries limits these gains. Overall, our efforts at environmental communication praxis have not generated significant public debate, but they have supported future coproduction by making scientists a more visible presence in the community and providing easy pathways for them to begin engaging the public. Finally, this research highlights an underappreciated barrier to public engagement: scientists are not merely disconnected from the public, but also connected in ways that may be functional for their research. Many field scientists, for example, seek out neutral and narrowly defined connections that permit research access but are largely incompatible with efforts to address controversial issues of environmental governance.  相似文献   
1000.
A decision support tool aiming to facilitate discussion and transparency in land-use planning processes has been developed. It includes process steps initiating with an analysis of the current situation, identification of relevant actions and sustainability analysis steps. The sustainability was subdivided into human health and environment, resources, and social and economic impacts. The main difference between this risk analysis tool and others is the allowance of comparisons of present risks and consequences of measures early in the process. It also includes assessments from short- and long-term perspectives, such as taking into account climate change. It combines classic risk analysis with life-cycle assessment procedure. It has been developed and tested in co-operation with municipalities. The tests show that the tool is applicable and can be relevant in the planning process. It offers an iterative discussion framework that is systematic, condensed and yet a simplistic way of describing consequences. The criticism is that it is regarded as time demanding, but this can be managed by preparatory work.  相似文献   
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