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991.
ABSTRACT: Typically, infrastructure agencies build massive water projects to serve expanding populations in emerging country cities, but collect and treat only a fraction of the resulting wastewater. This effluent often overwhelms existing sewerage systems and fouls waterways. Cleaning urban waterways requires large investments over long terms and the political will to make and sustain them. This challenge - difficult in advanced countries - becomes daunting with the scarce resources and weak institutions typical of emerging countries. This paper presents a framework to structure such a strategy, and applies it to Madras, India. It consists of three parts: (1) setting a vision through a participatory process; (2) macro investments mainly in wastewater treatment that use least-cost methods; and (3) micro investments in small projects that involve local people and galvanize public support. The macro investment, $350 million for Madras, appears very large, but averages out to $66 per capita, far below the $1,000-$2,000 typical of advanced country cities. Micro projects to be undertaken by Non-Governmental Organizations (NGOs) included an independent wastewater monitoring program, sanitary upgrading of slums along waterways banks, a cattle waste demonstration project, and an industrial pollution survey. Together, a macro/micro strategy promises the funding and political will to achieve a balanced vision of waterways quality.  相似文献   
992.
以福州市主城区1988年和2008年的TM影像为基础,对福州市主城区土地利用/覆被变化特征进行分析.结果表明:研究区1988-2008年期间土地利用结构发生了很大的变化,不同土地利用类型之间相互转化,其中建设用地面积剧增,导致不透水层的大面积增加.结合土地利用/覆被变化的水文效应分析表明,主城区土地利用/覆被变化对洪水的产流、汇流过程及河网水系结构产生很大的影响.  相似文献   
993.
秦祖兵 《四川环境》2000,19(4):35-36
经实验比较了涤沦仿真丝污水治理中常见的两种工艺即“厌氧酸化+好氧酸化”和“加酸沉淀+好氧生化”的处理效果,提出了后一种工艺才能真正治理污染的观点。加酸沉淀可去除CODcr77%左右,同时大大提高了污水的可生化性。  相似文献   
994.
In the recent decades, there have been frequent conflicts between groundwater resources and environmentally hazardous activities. An example is the construction of the new highway through the important glaciofluvial esker aquifer Nybroåsen, which passes the protection zone of the water supply for the Kalmar municipality, in the southeastern part of Sweden. The decision to build the new road through this important aquifer has been strongly questioned by the municipality and the public because the value of the water resources in Nybroåsen was not taken into consideration during the first phase of the decision-making process. Multicriteria decision aid (MCDA) is applied as a tool to structure and analyze the four road alternatives proposed in the environmental impact assessment for the above conflict. The alternatives, including the existing road, are in conflict with water resources, agriculture, natural, and cultural values. The impacts on the water resources have been predicted by a two-dimensional physically based time-variant flow and solute groundwater model, which has been calibrated and evaluated. The MCDA illustrates how it can be used to identify (1) actors and their concerns, (2) ranking of alternative road scenarios according to actors preferences, and (3) coalition groups of actors, i.e., groups that have similar views with regard to the road alternatives. The analysis shows that the two best compromise solutions obtained in the MCDA were unacceptable by the strongest coalition group, showing that either the family of criteria was not well chosen or new alternatives should have been developed.  相似文献   
995.
烟气脱硫技术的模糊评价   总被引:4,自引:1,他引:4  
应用模糊数学原理,将素质决策与数量决策相结合,以三种典型烟气脱硫技术为例,对所涉及的定性和定量指标进行处理,经模糊线性加权变换,评估和优选出适合我国国情,具有较好的环境,社会,经济效益的烟气脱硫技术,比较表明,模糊决策方法在脱硫技术的评估和优选中优于单一的素质决策或数量决策方法,是一种有前途的科学的定量化决策方法。  相似文献   
996.
模糊评价数学模型在企业安全评价中的应用   总被引:13,自引:1,他引:13  
模糊评价是利用模糊数学的基本理论--隶属度将模糊信息定量化,再对其进行定量评价得出科学结论的一种方法。该方法运用较普遍。介绍了该方法的基本原理,通过实例论述了它在企业安全评价中的应用。  相似文献   
997.
基于Petri网的城市突发事件应急联动救援系统性能分析   总被引:7,自引:3,他引:7  
随着我国城市化进程的加速,城市规模的日益扩大,城市需要及时有效地应对各种突发事件,满足城市居民对公共安全的需求.近年来,我国政府已开始在部分城市建设应急联动系统来处理可能发生的各种突发事件.笔者引入Petri网,对我国典型的城市重大突发事件应急联动系统的应急性能进行分析,初步建立城市重大事件应急联动系统的性能分析的Petri网模型.对Petri网模型更加深入的研究,将在后续课题中进一步开展.  相似文献   
998.
    
Accidents involving contractors continue to occur with regular frequency. By using the standard set within the PSM 29 CFR 1910.119(h) regulations, it has been identified that certain aspects of the way contractors do work are not up to the stipulated regulatory requirements especially regarding matters like not providing mandatory personal protective equipment (PPE) to the workers, not discussing hazards related to handling procedures with the workforce and improper control of non-routine activities during changes in shifts. The PSM 29 CFR 1910.119(h) regulations promulgated in 1992 provides standards that covered processes to obtain and evaluate data regarding contractors' health and safety programs as well as the contractors' performance evaluation. Many of the accidents involving contractors are direct result of poor training of contractors and/or poor control of the contracted work. Even though most organizations have their own contractor management systems, there are issues in meeting the requirements of PSM. The PSM standard only state “what to do” not “how to do it”. This is known as self-regulatory policy which depends on the industries understanding to interpret the standard that also contribute to this problem. This paper presents a structured and easy technique to plan and implement a practical and comprehensive contractors' management system in process industries that will comply with OSHA CFR 1910.119. A model has been developed based on this technique and its application has been tested in a pilot plant for compliance to PSM regulation. The model is beneficial to the process industries as any deficiencies in the PSM contractors' management program will be highlighted by the model which will then easily correct the identified deficiency so as to minimize and prevent catastrophic accidents.  相似文献   
999.
中国石油数字化应急预案系统研究   总被引:1,自引:0,他引:1  
中国石油高度重视应急预案体系建设工作,集团公司和所属企业均在风险分析的基础上,建立了“横向到边、纵向到底”的应急预案体系,为有效应对各类突发事件提供了重要的支持.旨在对文本应急预案的数字化应用技术进行研究,以进一步提高应急预案的可操作性.首先,探讨了数字化应急预案的概念,分析了国内外数字化应急预案系统技术的研究现状.其次,基于中国石油数字化应急预案系统的需求分析,从业务流程设计、系统部署设计和系统功能设计等三个方面对其进行了研究和分析.最后,立足于中国石油应急信息系统建设实际,提出了中国石油建设数字化预案系统建设的实施步骤.  相似文献   
1000.
为更深入研究无信号控制路段行人过街的交通特性,通过激光雷达采集行人过街过程中来车的运动状态数据,考虑外部因素对行人过街决策的影响及行人对安全过街的心理需求,利用人车间距、车辆速度和可穿越间隙等参数分析直接过街和等待过街2种决策结果下的数据特性。基于上述参数建立行人过街安全心理距离模型和多元Logistic回归决策模型,并验证模型有效性。结果表明:当人车间距越大、车速越低、可穿越间隙越大时,行人过街概率越大;相同可穿越间隙下,车速越快,行人过街概率越大;所建立二模型均有较高有效性。研究成果可为车载行人预警系统的优化提供依据。  相似文献   
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