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951.
ABSTRACT: A typical single family residence in Tucson, Arizona, was retrofitted to incorporate low-water-use fixtures and water reuse systems. The use of municipal water was reduced by 53 percent to 53 gallons per capita per day (gpcd) and total water use at the home was reduced by 33 percent to 74 gpcd.  相似文献   
952.
ABSTRACT: The search for an adequate methodology to quantify environmental trade-offs led to a simulation technique, the Priority Evaluator Technique (PET). The PET was applied to determine values and trade-off preferences for environmental variables related to a proposed reservoir project. The PET simulates real world situations and allows the respondents to evaluate their preferences within a fixed cost framework. It systematically checks the respondents's perception of the existing conditions and compares the changes sought. From the responses obtained via interviewing, one can establish the extent to which respondents are satisfied with the prevailing conditions, the magnitude and direction of changes sought, the quality trade-offs, and the relative value of different situations. The PET is flexible and can accommodate alternative planning decisions, prices, incomes, and end factors. The promise shown by this application of the PET should encourage further exploration and evaluation.  相似文献   
953.
石油化工储运系统的清洁生产   总被引:2,自引:0,他引:2  
介绍石油化工储运系统推行清洁生产的情况。运用浮顶罐技术,光纤或光导技术、高低液位报警技术等先进技术,实施清污分流,污污分汉及污油回收,消灭火炬回收炼厂气等方法,达到节约原材料,降低成本,清洁生产的目的。  相似文献   
954.
Contrary to earlier forecasts, the global greenhouse gas market will initially be characterised by low prices and a strong competition between the different Kyoto Mechanisms. The CDM involves higher transaction costs than the other mechanisms and has lost a considerable share of its ‘early start’ advantage due to the continuous delays in defining the CDM rules on the international level. Host countries will have to compete intensively for CDM investments. Thus the development of effective institutions is crucial to reap benefits from this market, especially if a unilateral strategy is chosen. Countries should develop approval criteria and sectoral priorities in a broad stakeholder consultation. Moreover, capacity building of local actors, information exchange as well as marketing has to be organised. Experience from several countries shows that clear competencies are crucial to get investor confidence. Long-term professional staff is also an important asset. Fights between ministries will scare off investors. The optimum institution will be a CDM Office that is independent but has full approval powers. A second-best solution is a two-tiered system. A CDM Board with representatives of ministries would define criteria and priorities whereas a CDM Secretariat would evaluate (and possibly approve) project proposals and do outreach and marketing. Small countries would preferably use the existing focal point of the UNFCCC and flexibly involve consultants if project proposalscome in. Even under an optimal institutional structure, CDM projects will only be implemented if financing and contractual issues can be resolved. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
955.
中国南方石灰岩荒山开发利用新探   总被引:11,自引:0,他引:11  
我国南方石灰岩荒山分布范围广阔,目前荒山上的植被和自然环境在人类长期掠夺性农业活动的干预下向逆向演替。对这种生产力十分低下的荒山如何合理利用是一个远未解决的问题。本文在对石灰岩山地环境逆向演替的过程、根源与危害和现有的各种利用方式作出系统分析与评价的基础上,提出了一种在石灰岩荒山发展豆科灌木饲料的新的利用方式。这种新的利用方式将有可能为石灰岩荒山的开发利用开创一条新路,也是南方石灰岩山区一项有深远意义的绿色工程。  相似文献   
956.
Abstract: The sufficiency and usefulness of Effective Efficiency (EE) as a water resources index is shown through conceptual formulation of a generalized EE and practical applications. Two EE models are proposed: one is based on water quantity and the other on quantity and quality, with the possibility of considering water reuse (recycling) in both. These models were developed for two scales: the first is called Project EE and the second Basin EE. The latter gives the influence of the project on the water resources systems of the basin while the former does not make such connection to the whole basin. Such considerations give proper signals as to the adequacy of any intervention to increase efficiency. A crucial distinction is made between depletion and diversion water savings. Classical Efficiency (CE) models are analyzed and compared with the various EE models. CE results in values that are less than EE because of not considering water reuse and water quality in its calculation. Some authors, pointing to these problems – particularly the first problem – have advocated the use of hydrological “fractions” instead of efficiency concepts. This paper defends the use of a proper efficiency model such as EE and suggests putting an end to the use of the CE indicators. To test the models, they are applied to five cases of irrigation and city water use in the United States and Egypt. The analysis of the results demonstrates all the points mentioned above and the potential of the EE models to adequately describe the water resources efficiency and sustainability at a location.  相似文献   
957.
根据《京都议定书》关于清洁发展机制(Clean Development Mechanism,CDM)的目标、设立条件、步骤和监管制度的规定,指出了中国在实施清洁发展机制中所获得的环境、社会和经济方面的巨大利益,同时,也分析了目前中国实施清洁发展机制在项目发展规模、潜在项目识别、额外行证明、CER法律权属界定、项目签发等方面存在的问题。文章结合国际社会清洁发展制度的趋势走向,预测在今后相当长的时期内清洁发展机制仍将作为全球温室气体减排的有效制度而存在,并将对CDM宗旨重新定位和完善CDM项目具体实施制度。还根据国际形势变化,对2012年后中国清洁发展机制的法律制度建设提出了具体的建议:应尽快出台一部能源基本法,使得包括清洁能源机制在内的应对气候变化的措施能够有法可依。立法中应重点确立能源可持续发展原则,具体规定CDM项目适格标准、改变传统一元所有权模式,明确CER法律权属和所有权、完善CDM项目监管制度,以限制CDM项目单纯追求经济效益的危险性、加强CDM服务行业规范,提高CER签发率。  相似文献   
958.
以乌鲁木齐市区高压输变电工程为研究对象,重点论述了城市高压输变电工程电磁辐射产生的机理、特征及危害,并通过实地监测,说明了城市高压输变电工程电磁辐射水平现状及发展趋势,以国家电磁辐射环境保护法律法规及技术标准为准则,从多方面提出了城市高压输变电工程电磁辐射的污染防治措施。  相似文献   
959.
高速公路建设-运营-移交(BOT)项目风险管理研究   总被引:2,自引:0,他引:2  
从风险的普遍性和特殊性出发,分析高速公路建设-运营-移交(BOT)项目的风险特征;笔者认为,基于我国高速公路BOT实施现状分析,指出相关法律法规不完善、市场理念缺乏、风险意识淡薄、风险分担责任不明和缺乏相应的风险管理人才是目前我国高速公路BOT项目实施存在的主要问题;树立风险意识、完善市场体系、监理健全法律法规、合理分担风险、培养和引进专业风险管理人才是高速公路BOT项目风险管理的有效对策。  相似文献   
960.
交通建设工程安全评价技术现状及趋势研究   总被引:5,自引:3,他引:2  
综述我国交通建设工程安全生产现状,详细描述常用安全评价技术在我国交通建设工程中的实用状况,对专家论证、安全检查表、作业条件危险性评价等常用安全评价方法的适用范围及优缺点加以分析。系统研讨安监系统及建设部门制定涉及安全评价的相关规定及其应用情况。对国内外工程建设安全评价方法的定量化、软件化等研发进展进行讨论,同时对我国交通建设工程安全评价技术发展趋势给以展望。  相似文献   
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