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861.
This study estimated a series of indicators to assess the energy security of supply and global and local environmental impacts under different mitigation scenarios through 2050 in Brazil, designed with the integrated optimization energy system model MESSAGE‐BRAZIL. The assessment of interactions between environmental impacts and energy security dimensions was complemented through the application of life cycle assessment (LCA) methodology. Overall results imply energy security establishes more synergies than trade‐offs in increasingly stringent mitigation scenarios, especially patent within the sustainability dimension, which increases energy security and provides additional benefits regarding climate change mitigation and air pollution emissions. It is still necessary to extend analysis to other energy sectors in addition to the power supply sector and to promote a better understanding of repercussions of energy scenario expansion in energy security.  相似文献   
862.
基于城市生态安全内涵,运用PSR(压力-状态-响应)模型建立了宁波市生态安全评价指标体系,并以最大信息熵原理(MIEP)为基础,自组织特征映射神经网络(SOFM)为算法,借助MATLAB数学软件为计算平台,从复杂系统结构演化的角度提出了城市生态安全评价模型.最后,用MIEP模型对宁波市2002—2011年的城市生态安全进行评价.结果表明,2002—2011年宁波市生态安全水平逐年提高,2002—2009年处于临界安全状态,2010、2011年处于较安全状态.由于MIEP模型能较好地体现城市生态安全的时空演变动力学特性,连接权值的获取避免了人为设定的主观性,故在城市生态安全评价中有较明显的优势,且在预测上有一定的潜力.  相似文献   
863.
In 2004, as a response to the discovery of Bovine Spongiform Encephalopathy in Canadian cattle and other food scares, the Province of British Columbia (BC) developed a comprehensive set of meat inspection regulations, increasing the requirements for food safety infrastructure. Through a series of interviews with farmers and stakeholders, we highlight some of the unintended consequences for community food security and sustainability that resulted from these stringent safety regulations in rural and remote communities in BC. These include the loss of meat production and processing capacities as well as the erosion of local food practices and traditions through the criminalisation of farm-gate sales. We suggest that food safety regulations intended to protect consumer health may result in negative effects for community food security and rural sustainability and that these consequences should be accounted for when developing food policy.  相似文献   
864.
Despite their opposition to the dominant agri-food system, alternative agri-food initiatives may unwittingly reproduce central features of neoliberalism. Julie Guthman has been a particularly strong proponent of this view, arguing that food activism and neoliberalism have shaped one another dialectically in California in recent decades. This paper responds to her argument, with a view to distinguishing between what it reveals and what it may conceal about the transformative potential of alternative agri-food initiatives in North America. Drawing on primary research on a variety of community-based food initiatives in Eastern Ontario, Canada, we show how a neoliberal lens does help to illuminate some problematic characteristics of these initiatives, including assumptions about market-based solutions and focus on self-improvement at the expense of state involvement. However, this lens underestimates those aspects of community-based food initiatives that may appear commensurate with neoliberal rationalities but which also push in more progressive directions.  相似文献   
865.
Security incidents around the world causes enormous loss in terms of life, economy, and environment. The 9/11 ′triggered the serious onset of research initiatives in the field of security with a more specific focus on the protection of high sensitive and hazardous facilities. It is well known that technology is advancing in a very rapid phase, proportionally increasing the security risk of the facilities. Conventional deterministic risk techniques widely found their applications in the earlier stage but owing to the increasing dynamic nature of the security risk, probabilistic dynamic risk assessment models were developed over time. In this article, the authors attempted to present the evolution of security risk concepts, their present status, and their future scope in a precise and consolidated form. The last 20 years of development in the security risk assessment concept involving deterministic and dynamic risk assessment models and applications in security risk assessment relevant to physical security are discussed in this article. The objective of the article is to outline the past, current and future directions of security risk highlighting their strength, weakness and limitations.  相似文献   
866.
中国区域能源安全供给脆弱性分析   总被引:4,自引:0,他引:4  
随着经济持续快速发展,我国能源需求不断增加,能源安全,尤其是石油安全问题日益突出,而能源安全供给脆弱性是能源安全的核心问题.在对能源安全供给脆弱性概念进行界定的基础上,构建了脆弱性评估模型以及由对外依存度、能源消耗弹性指数、能源储量比、能源生产弹性指数、运输线路长度和人均GDP构成的评价指标体系.采用因子分析法确定评价指标的权重系数,并对全国30个省(市、区)"十五"时期的常规能源(煤炭、石油和天然气)安全供给脆弱性进行定量评估.结果表明:①我国区域能源安全供给脆弱性程度整体上处于中等偏下水平,且呈现出"东高西低"的特征;②能源安全供给风险的应对能力差异是区域脆弱性分异的主导因素.  相似文献   
867.
结合对谭家山煤矿矿区地质环境破坏、环境污染等灾害现状的调查与研究,探讨煤矿生产所导致的地面塌陷及裂缝、矿震、边坡失稳与滑坡、矿区土地损毁、大气污染、水污染、土壤污染等灾害所引发的矿区人居环境安全问题;提出煤矿住区的建设不但要遵循一般的建设原则;还要针对威胁人居安全的各种具体灾害采取特殊的建设技术。笔者认为,可以通过对住区功能环境、环保环境、安全环境、人文环境等方面的建设,来实现矿区人居环境安全的改善,以减轻煤矿区不利的环境因素对住区的影响。  相似文献   
868.
围绕智能建筑的安全防范系统,依据安全防范系统的理论,综合分析安全防范系统的人防、物防和技防三种防范手段,构建了智能建筑安全防范系统的综合分析框架。借鉴系统安全中"人、机、环境"以及管理的分析方法,从人的因素、机的因素、环境因素、管理因素以及其他因素等五个方面出发,建立了智能建筑安全防范系统的评价指标体系。并采用层次分析法和模糊综合评价方法构建了智能建筑安全防范系统的综合评价模型。然后以此为基础,结合实例分析来说明评价指标的有效性,最后针对实例提出了对策措施。  相似文献   
869.
研究地铁施工引起地下管线变形的安全评估方法,分析三点共圆法求算管线变形曲率中测点间距和测量误差的影响,并对其适用性及相关问题进行了探讨;提出利用六次多项式曲线拟合求算管线变形曲率的方法,并结合工程实例阐述其应用.  相似文献   
870.
From the angle of the supply stability and use security, this article has constructed an appraisal indexes system and established the strategic evaluation model for the security of Chinese petroleum by using the gray correlated method. The article then made an empirical research on the bases of the data from 1990 to 2006. The result indicated that the security level of China's petroleum presents an undulatory and slow ascend tendency. This attributed to the combined function of the oil production, the optimization of economical system, and the technology advancement in the energy domain. At the same time, the undulatory slow enhancement from the environmental protection effect, which is led by the conservation of energy in GDP, has greatly influenced the use security of petroleum, and its undulation has attacked the stable function to the humanity effect in the petroleum use security, and it has caused the short-term undulation to the petroleum use security level, as well as the China's petroleum security. It is the most important way for China's petroleum security that synthesis considering the influence factor and the development tendency and promoting the benign function mechanism to be formed to China's petroleum security from the angles of economy growth, petroleum supply, technology advancement, environmental protection, and humanities development.  相似文献   
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