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991.
Urban planning involves compromise between the diverse and often contradictory issues supported by the different stakeholders. The literature generally agrees on the need to broaden the participation base to overcome this difficulty. However, participation should not be limited to problem solving, but should also take place in the problem setting phase. This paper proposes a participatory diagnosis process for structuring the problem setting phase. We describe an experiment in a participatory diagnosis conducted with the residents of a Geneva neighborhood. The experiment began by identifying the residents' concerns, which were then reformulated under broader issues. Some 20 spatial indicators were built using GIS tools, and were then applied in a second phase of resident consultations to assess the relative importance of each issue. The ensuing priority issues formed the core of the diagnosis. The approach emphasized comparison between the daily experiences of residents and so-called official information (i.e. census tract, traffic measurement, and so on). The residents were therefore involved in a learning process that allowed them to consolidate or modify their opinions. The process led to the emergence of a clearly defined collective awareness that supplanted individual aspirations.  相似文献   
992.
工业开发区区域环评的特点   总被引:5,自引:0,他引:5  
从工业区域开发与单项建设项目的区别入手 ,阐述工业开发区区域环境评价的特点 ,并提出区域环评中在技术方法上需要进一步丰富和发展的工作内容。  相似文献   
993.
As the nations of the world negotiate future controls on greenhouse gas emissions, a critical environmental policy issue becomes understanding the multiple environmental consequences of these controls. Here we describe an integrated assessment model for quantifying multiple environmental impacts of large-scale environmental initiatives and apply this model to climate change mitigation. Our analysis shows that reductions in global warming will be accompanied by reductions in ozone depletion, acid rain and mercury emissions, and desulfurization waste generation. We also conclude that the largest collateral benefits from reducing global climate change may be in the developing world. This result is critical since it is the developing nations who ultimately control the long-term success of any climate stabilization strategy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
994.
基于空间信息技术的城市环境时空调控范式研究   总被引:1,自引:0,他引:1  
城市环境-生态系统是高度复杂的时空复合动力学系统。通过对城市环境问题的空间动力学机制分析后,提出城市环境可持续发展时空调控的层次途径,并构造了融合遥感、地理信息系统等空间信息技术、环境建模技术、决策支持系统、人工智能等技术的城市生态-环境系统时空调控的体系框架,为城市环境管理及环境空间决策提供新的理论范。  相似文献   
995.
To reduce excess sludge, a Tubificidae reactor was combined with an integrated oxidation ditch with vertical circle (IODVC), and a new integrated system was developed for wastewater treatment. A pilot-scale of this integrated system was tested to investigate the sludge reduction with Tubificidae and the impact on effluent quality and sludge production. The dominant worm was Branchnria Sowerbyi in the Tubificidae reactor after inoculation of Branchnria Sowerbyi and Limnodrilns sp., and the maximal volume density of wet Tubificidae in vessels of the Tubificidae reactor was 17600 g/m3. Two operational modes, treating the excess sludge (first mode) and the returned sludge (second mode) of IODVC by the Tubificidae reactor, were used in this experiment. The results showed that the excess sludge reduction rate was 46.4% in the first mode, and the average sludge yield of the integrated system was 6.19×10-5 kg SS/kg COD in the second mode. Though the sludge returned to IODVC via the Tubificidae reactor, it had little impact on the effluent quality and the sludge characteristics of the IODVC. No new type of recalcitrant substance in the supernatant was discharged into the environment when the sludge was treated by Tubificidae. The experimental results also indicated that no significant changes occurred on the viscosity, specific resistance, and the floc size distribution of the sludge.  相似文献   
996.
Ecosystem risk is a new concept in understanding environmental problems. It is important to study and develop quantitative methods for regional ecosystem risk analysis. In this study, some new indicators and methods for measuring oasis ecosystem risk were established using reliability theory. These indicators are linked to water resource, which is the key restricting factor in arid area oasis ecosystems. They have clear meanings and can also be compared in different arid area oases. A case study in the Liangzhou oasis of the Shiyang River Basin in China shows how to calculate these ecosystem risk indicators. The results of the case study are as follows: the reliability indicator, risk indicator, stability indicator, and integrated loss indicator of the Liangzhou oasis are 0.686, 0.314, 0.743, and 0.301, respectively. This means that the reliability degree of the oasis's ecosystem safety is 68.6%; the degree of risk that it is unsafe is 31.4%; the stability degree is 74.3%; and 30.1% of the oasis's area is supported by over-exploiting underground water and damaging the lower reaches of the ecosystem. This result can be used as a guide in controlling and managing ecosystem risk in the research area.  相似文献   
997.
王斌  余刚  黄俊  胡洪营 《环境科学》2007,28(8):1774-1778
应用种间相关估算(ICE)方法预测50种硝基芳烃缺失的生物毒性数据,对通过ICE计算获得的各种生物毒性数据进行主成分分析(PCA),计算综合毒性因子(ITI),进行综合毒性评价.结果表明,除了黄瓜种子发芽抑制毒性以外,其他各种生物毒性都在1%的显著水平上呈显著的线性正相关.硝基芳烃的这些生物毒性机制基本相似,因此应用ICE方法预测其毒性数据是可行的.QSAR分析表明,ITI与分子最低未占轨道能Elumo有显著的相关性,r=0.869,表明亲电反应性是硝基芳烃的各种生物毒性所综合反映的主要致毒机理.基于ICE和PCA方法计算得到的ITI与基于QSAR和PCA方法计算得到的ITI的大小趋势具有一致性,ICE与PCA方法的联合应用可以成功地评价和预测硝基芳烃的综合毒性.  相似文献   
998.
为解决分接开关故障诊断以主观经验、缺乏系统化流程以及诊断结果与分接开关实际发生故障存在偏差等问题,依据当前分接开关主要故障分类,提出基于模糊Petri网的有载分接开关故障诊断模型,并结合分接开关典型故障案例,验证模型有效性。研究结果表明:基于模糊Petri网的分接开关故障诊断模型能够有效处理故障概率中不确定性因素,具有容错性好、运行效率高等优势,研究结果可为提高分接开关故障诊断的准确性、保障电力系统安全稳定运行提供参考。  相似文献   
999.
曝气-过滤一体化装置将生物反应器与过滤机理有机结合,较好地维持了反应器中的高污泥浓度,实现了水力停留时间(HRT)与污泥停留时间的分离。采用连续流间歇曝气工艺对该装置的脱氮除磷效果进行了研究。实验结果表明:在HRT为8h,运行方式为曝气2h、停曝2h的条件下,COD去除率为95.55%,NH3-N未检出,TN为84.90%,TP为93.69%,出水各项指标都达到了GB8978-1996(污水综合排放标准》一级排放标准要求。  相似文献   
1000.
城市生活垃圾综合管理决策模型研究进展   总被引:1,自引:0,他引:1  
生活垃圾综合管理模型已广泛应用于城市生活垃圾综合管理方案的制订.概述了国外用于城市生活垃圾综合管理决策的主要模型及其研究进展,包括费用-效益分析模型、生命周期评价模型和多目标决策分析模型.在分析国内该领域的研究现状和存在问题的基础上,提出了中国今后开展城市生活垃圾综合管理决策与模型研究的建议.  相似文献   
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