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961.
一种新的结构可靠度通用计算方法   总被引:1,自引:0,他引:1  
根据可靠度指标β的几何定义,运用具有全局优化能力的改进遗传算法,提出一种新的结构可靠度通用计算方法。针对可靠度几何优化模型搜索区域大而可行区域小的特点,在可靠区域和失效区域分别产生初始种群,在两种群之间通过不断迭代的二分法,使二分点不断接近极限状态曲面(线),从而产生可行解。对可行解进行选择、交叉、变异,最后求出全局最优解。该方法不需要使用结构功能函数的偏导数,对于功能函数不能明确表达的可靠度问题尤为适用;对于功能函数可以明确表达但求导复杂的问题,可省去求导过程;可任意设定初始值,且不受结构功能函数凹凸性的限制;通过算例验证,所提方法具有较高的精度和效率。  相似文献   
962.
电子废弃物已成为城市环境的新压力。本文从加强立法、生产者负责制以及建立健康绿色的废旧电子回收体系三方面分析电子废物变废为宝的绿色途径,从而推动电子废物资源化、无害化发展。  相似文献   
963.
Abstract: A decision support system for sustainable water resources management in a water conflict resolution framework is developed to identify and evaluate a range of acceptable alternatives for the Geum River Basin in Korea and to facilitate strategies that will result in sustainable water resource management. Working with stakeholders in a “shared vision modeling” framework, sustainable management strategies are created to illustrate system tradeoffs as well as long‐term system planning. A multi‐criterion decision‐making (MCDM) approach using subjective scales is utilized to evaluate the complex water resource allocation and management tradeoffs between stakeholders and system objectives. The procedures used in this study include the development of a “shared vision model,” a simulated decision‐making support system (as a tool for sustainable water management strategies associated with water conflicts, management options, and planning criteria), and the application of MCDM techniques for evaluating alternatives provided by the model. The research results demonstrate the utility of the sustainable water resource management model in aid of MCDM techniques in facilitating flexibility during initial stages of alternative identification and evaluation in a basin suffering from severe water conflicts.  相似文献   
964.
新疆生产建设兵团(简称兵团)的中小企业在兵团经济中占有重要地位,但在企业发展的同时,在污染负荷中所占的比例也在相应地上升。本文分析了兵团中小企业的发展现状及带来的环境问题,并提出了解决对策。  相似文献   
965.
We present a multi-model ensemble study for the Baltic Sea, and investigate the combined impact of changing climate, external nutrient supply, and fisheries on the marine ecosystem. The applied regional climate system model contains state-of-the-art component models for the atmosphere, sea ice, ocean, land surface, terrestrial and marine biogeochemistry, and marine food-web. Time-dependent scenario simulations for the period 1960–2100 are performed and uncertainties of future projections are estimated. In addition, reconstructions since 1850 are carried out to evaluate the models sensitivity to external stressors on long time scales. Information from scenario simulations are used to support decision-makers and stakeholders and to raise awareness of climate change, environmental problems, and possible abatement strategies among the general public using geovisualization. It is concluded that the study results are relevant for the Baltic Sea Action Plan of the Helsinki Commission.  相似文献   
966.
Assessing the sustainability of large public investment projects within the general framework of three-pillar thinking is a complex affair. Such ventures involve multiple actors – e.g. planners from various disciplines such as engineers, economists and social scientists, in addition to politicians, users and other people affected – each carrying with them particular agendas and priorities, and corresponding understandings of the concept of sustainability. In this paper, we propose to frame the concept of sustainability assessment within the context of investment projects, in order to enable communication between the multiple actors, to assess different impacts of an investment project against one another in a meaningful way and, ultimately, to enhance the commensurability of investment project alternatives. Our main idea is that there exist different levels according to which the assessment of sustainability ought to refer – operational, tactical and strategic – and that properly addressing these levels can permit the different actors to comprehend one another, and thereby allow for more clarity and positive action.  相似文献   
967.
以曼么村为例 ,从环境经济学的观点出发 ,对热带森林 -砂仁生态系统的可持续性从经济及环境、生态等方面进行了分析。发现种植砂仁后 ,砂仁的经济效益的递增率不如资源环境成本的递增率快。生态环境的破坏 ,大大降低了砂仁的产量 ,从而更使得种植砂仁的经济效益停滞不前。由砂仁的外延式生产转为内涵式生产 ,采用轮作的经营方式 ,能很好地实现砂仁的持续种植  相似文献   
968.
This paper presents the externalities of sulfur dioxide (SO2) in the Taichung metropolitan, Taiwan. The human effects of SO2 from stationary sources are a key element for local air quality management. A methodology to evaluate those effects in monetary term had been adapted and applied. This method was modified from the EU-based impact pathway approach link to the skill of geographic information systems. The studied area was divided into 66 districts and the quantity of SO2 was allocated to each district. Then, the ambient concentration of SO2 was estimated by using the ordinary kriging method. A risk analysis was employed to characterize the health impacts caused by SO2. Finally, a monetary transfer approach based on the European data was conducted to estimate local damage costs per ton of SO2. Health impacts, especially acute mortality, dominate in term of costs. The calculation showed that damage costs ranged from 0.56 to 7.38 USD/kg SO2 based on the 2002 emission data. The results could be used in the internalization of SO2 externalities and management of the stationary sources in the studied area. This paper also concludes that the externalities caused by stationary-related SO2 emissions are some 28.5 million US dollars in Taichung metropolitan (Taiwan) in 2002.  相似文献   
969.
碳减排是当前国际政治、经济和环境保护战略斗争的新领域。昌吉州的碳减排工作在新疆具有一定的示范意义,昌吉州目前所排放的二氧化碳主要来自于燃煤、建筑取暖、农业生产及居民生活等方面。现阶段可通过发展循环经济、走可持续发展道路,加强节能减排和植树造林,提倡节约、减少浪费,发展绿色生态农业,积极开发清洁能源,发展新能源等方式来发展低碳经济,降低昌吉州的二氧化碳排放量,为国家减少碳排放的战略目标做出自己的贡献。  相似文献   
970.
结合主要污染物"十二五"总量控制规划编制工作经验,对新疆畜禽养殖业主要污染物的减排潜力及途径进行分析,宏观测算出新疆畜禽养殖业"十二五"期间的减排潜力,并提出新疆畜禽养殖业的减排途径及方法,为新疆主要污染物"十二五"减排工作提供合理化建议。  相似文献   
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