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891.
基于群决策的河流允许排污量公平分配博弈模型   总被引:3,自引:2,他引:3  
为解决河流水质管理中允许排污量的公平分配问题,建立一个由排污者群体决策的博弈模型.其基本原理是在现有被普遍接受的公平分配准则基础上,排污者按照一定的顺序,根据个体利益最大化原则依次选择分配准则并获得相应的允许排污量,同时考虑所有排序方式,求取平均值作为最终分配结果.案例研究结果表明,模型综合考虑了多种分配准则,无需人为给定准则的权重,保证了分配依据和分配过程的公正,由排污者群体决策而得出最终结果,是一种较为公平合理的允许排污量分配方法.模型求解与博弈论的Shapley解法类似,计算量呈随排污者个数阶乘递增趋势.  相似文献   
892.
含砷污泥制砖的毒性浸出试验研究   总被引:2,自引:0,他引:2  
将含砷污泥和粘土按一定比例混合制砖,并对样品砖的毒性浸出进行了研究。结果表明对As、Zn、Pb、Cd离子的固化效果好,浸出毒性低于国家标准。还分析了浸出液的pH值、Eh和溶解氧对重金属离子浸出浓度的影响。  相似文献   
893.
The transition towards a circular bioeconomy (CBE) in the European Union is not without contestation. In particular, research has highlighted potential trade-offs of the large-scale production of bio-resources, for instance with environmental quality goals. To date, however, it remains underexplored in the CBE literature how controversies develop throughout a transition process. To address this gap, this paper explores where controversies are situated in a transition, how they change throughout, and how they influence the transition process. First, we suggest that controversies can be situated on and between different system layers within a transition. Second, we offer an explanation of how controversies evolve, as actors confirm, integrate, disintegrate and polarize underlying storylines. Third, these controversies can have both productive and unproductive outcomes while they unfold throughout a transition. We illustrate this understanding with the example of biorefineries as CBE key technology and discuss a research agenda on controversies in sustainability transitions.  相似文献   
894.
In this research, the impact of several water conservation policies and return flow credits on the fate of water used outdoors in an arid region is evaluated using system dynamics modeling approach. Return flow credits is a strategy where flow credits are obtained for treated wastewater returned to a water body, allowing for the withdrawal of additional water equal to the amount returned as treated wastewater. In the return credit strategy, treated wastewater becomes a resource. This strategy creates a conundrum in which conservation may lead to an apparent decrease in water supply because less wastewater is generated and returned to water body. The water system of the arid Las Vegas Valley in Nevada, USA is used as basis for the dynamic model. The model explores various conservation scenarios to attain the daily per capita demand target of 752 l by 2035: (i) status quo situation where conservation is not implemented, (ii) conserving water only on the outdoor side, (iii) conserving water 67% outdoor and 33% indoor, (iv) conserving equal water both in the indoor and outdoor use (v) conserving water only on the indoor side. The model is validated on data from 1993 to 2008 and future simulations are carried out up to 2035. The results show that a substantial portion of the water used outdoor either evapo-transpires (ET) or infiltrates to shallow groundwater (SGW). Sensitivity analysis indicated that seepage to groundwater is more susceptible to ET compared to any other variable. The all outdoor conservation scenario resulted in the highest return flow credits and the least ET and SGW. A major contribution of this paper is in addressing the water management issues that arise when wastewater is considered as a resource and developing appropriate conservation policies in this backdrop. The results obtained can be a guide in developing outdoor water conservation policies in arid regions.  相似文献   
895.
This article deals with the use of the procurement or purchasing power of governments to protect the environment. The focus is on South Africa and the aim is to show that South African organs of state can use procurement as an environmental policy tool to contribute to sustainable development as they have commendably done so to address past discriminatory policies and practices. It is argued that such use does not fall outside the current legislative framework governing procurement and suggestions are made as to how environmental considerations could be incorporated throughout the procurement process, namely the preparatory stage; the drawing up of tender or technical specifications; ensuring the capability or responsibility of contractors; the use of criteria to compare different tenders; and ensuring that eventual performance under a contract is environmentally sound.  相似文献   
896.
Mineral development has contributed greatly to China's economic and social development. Many challenges remain, however, including environmental pollution and resource waste in practice, as well as a dearth of systematic theoretical research. The goal of this study is to analyze the economic and social effects of various mineral developments in China from diversified perspectives, so as to provide the basis for the formulation of China's mineral development policy. The input–output effects, industrial linkage effects and income distribution effects of different mining industries are quantitatively analyzed by adopting basic hypotheses of input–output economics, industrial linkage model and income distribution antitheses based on the latest available official data from China Statistical Yearbook from 2004 to 2010 and the 2007 Input–Output Table of China. The empirical results obtained in this study indicate that all mineral development industries, especially coal mining and washing, and petroleum and natural gas extraction industries, have given a strong impetus to the increase of China's fixed asset investment and GDP. Moreover, they have provided a large number of jobs, thereby alleviating ongoing employment pressure, and they have also played a positive role in promoting China's technology investment. The analysis of industrial linkages demonstrates that mining industries are basic to the national economy and produce a significant impetus to its downstream industries, but create weak pull effects in terms of national economic development. From the perspective of income distribution, mining industries play an important role in increasing China's fiscal revenue and per capital income. Hence, China's mineral development policy should (1) encourage additional investment in technology for exploration and development to insure sufficient supply and expand the input effects; (2) attract additional talent to work in remote regions; (3) optimize the industrial structure and promote the industrial transformation in resource regions; (4) adjust the interest distribution between the central and local governments to enable the local regions to become more self-sufficient; and (5) enhance the legal environment so that companies can more readily undertake their social responsibilities voluntarily.  相似文献   
897.
我国城市大气污染控制综合管理对策   总被引:19,自引:0,他引:19  
为探索"十二五"期间我国大气污染控制途径,本文针对我国大气颗粒物污染的区域性、复合性、复杂性特征和控制与治理任务的严峻形势,在回顾、总结和系统分析我国大气污染控制的历程和经验基础上,解析我国大气颗粒物的主要来源和途径,探讨大气颗粒物控制综合管理模式,提出大气颗粒物污染控制的相应政策建议。当前颗粒物成为我国大气污染最主要的污染物,且成为城市环境质量达标的关键指标,而目前大气环境质量管理体制和政策不能有效地解决颗粒物污染问题。因此,必须以保护人民身体健康为出发点,以改善城市和区域大气环境质量为目标,以削减一次颗粒物排放量为主线,以控制PM10、PM2.5以及其他污染物为重点,以科学的环境政策和产业与能源战略优化经济发展,综合运用法律、经济、信息、行政、技术等综合措施,尽快制定实施《城市环境空气质量综合管理办法》和《城市环境空气质量达标规划编制技术指南》,构建全国大气颗粒物污染控制政策措施体系。  相似文献   
898.
论龙须草的开发价值及在我国的利用现状与展望   总被引:14,自引:0,他引:14  
龙须草(Eulaliopsis binata)是中国、印度等亚洲少数国家特有的野生资源植物,在我国西南山区极富有开发价值。本文从龙须草的经济效益、生态效益、社会效益诸方面详细论述了龙须草在促进山区人民脱贫致富、解决山区剩余劳动力、缓解造纸原料短缺现状、增加纸张品种与品位、治理水土流失、恢复生态平衡等方面的独特作用;分析了我国开发利用龙须草资源的现状,指出“建立全国性生产、供销、科学研究一体化协作组织”、“开展驯化龙须草为栽培作物的系统研究”、“开展国际学术交流”等为当前龙须草开发与应用急需解决的7大课题。  相似文献   
899.
我国二恶英和多氯联苯的研究现状及对策分析   总被引:1,自引:0,他引:1  
为了解二恶英(PCDD/Fs)和多氯联苯(PCBs)在中国的研究水平、研究能力和驱动力,本文对有关研究论文的数量、题材、内容、资助来源和研究机构进行了系统调查和分析。调查发现,国内相关研究尚处在起步阶段,研究的方向和重点还需要进一步调整,研究能力有限,研究机构间合作交流不充分。针对这些问题,提出了相应的对策建议。  相似文献   
900.
基于多属性决策方法的饮用水健康风险全面评价   总被引:2,自引:0,他引:2  
分别从整体和单个指标两方面对饮用水的健康风险进行全面评价。整体评价方面,引入多属性决策方法对饮用水进行覆盖全部指标的健康风险评价。在给出指标不达标阈概念的基础上,提出了一个以指标从达标到不达标阈的敏感度为依据计算指标权重的方法。单个指标的健康风险评价方面,应用目前美国环保局推荐的健康风险评价模型对饮用水中的重金属指标进行健康风险评价,改进饮用水中污染物为有机物的健康风险评价模型达到对饮用水中的有机物指标进行健康风险合理评价。最后给出一个算例对所提方法进行了验证。结果表明,将多属性方法与目前普遍使用的健康风险评价方法结合起来使用能够实现从整体上和单个指标上对饮用水健康风险进行全面评价,从而更具实效性。  相似文献   
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