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161.
An innovative approach is introduced for helping developing countries to make their development more sustainable, and also to reduce greenhouse gas (GHG) emissions as a co-benefit. Such an approach is proposed as part of the multilateral framework on climate change. The concept of sustainable development policies and measures (SD-PAMs) is outlined, making clear that it is distinct from many other approaches in starting from development rather than explicit climate targets. The potential of SD-PAMs is illustrated with a case-study of energy efficiency in South Africa, drawing on energy modelling for the use of electricity in industry. The results show multiple benefits both for local sustainable development and for mitigating global climate change. The benefits of industrial energy efficiency in South Africa include significant reductions in local air pollutants; improved environmental health; creation of additional jobs; reduced electricity demand; and delays in new investments in electricity generation. The co-benefit of reducing GHG emissions could result in a reduction of as much as 5% of SA's total projected energy CO2 emissions by 2020. Institutional support and policy guidance is needed at both the international and national level to realize the potential of SD-PAMs. This analysis demonstrates that if countries begin to act early to move towards greater sustainability, they will also start to bend the curve of their emissions path.  相似文献   
162.
《Climate Policy》2013,13(2-3):247-254
Abstract

Continued growth and the privatisation of Brazil's electricity system, which is largely based upon hydropower, is projected to lead to big expansion mainly of natural gas but also coal power stations with a resulting huge growth in greenhouse gases (GHG) emissions unless steps are taken to avoid this. The Brazilian National Program of Power Conservation and Efficient Use of Electrical Energy in terms of avoided GHG emissions (PROCEL), originally created in 1985, is a multi-stakeholder program coordinated by Eletrobrás aimed to reduce the waste of electrical power on both supply and demand side. Initially crippled by lack of funds, a new finance structure introduced in 1994 has greatly increased PROCEL's impact. Here we develop scenarios that suggest that continued expansion of PROCEL's programme, including resources that might be drawn through clean development mechanism (CDM) projects, to meet projected PROCEL targets over the next two decades could avoid approximately one-third of the GHG emissions from the Brazilian power sector. This contribution demonstrates the significant global environmental benefits of PROCEL in addition to national benefits of this innovative programme.  相似文献   
163.
从宽带脉冲泵浦光的光谱及滤光片的滤光特性参数出发,分析了自发参量下转换(SPDC)产生纠缠光源的系统中各类滤光片对剩余脉冲泵浦光的滤除效率。分析结果表明,适当组合不同类型的滤光片可以有效地滤除剩余脉冲泵浦光,并从实验上验证了分析结果的正确性。该研究为脉冲泵浦光条件下SPDC过程产生的纠缠光源的有效测量提供了理论指导和实验验证。  相似文献   
164.
根据印度洋西北部鸢乌贼(Symplectoteuthis oualaniensis)作业渔场的现场调查数据,分析了作业水深、作业时段、摄食等级和月相等因子对手钓上钩率的影响。统计表明,晚上、午夜和凌晨3个不同时段和不同作业水深对手钓上钩率均有显著性影响。3个时段中,其摄食等级呈先低后高再低的现象。午夜和凌晨,上钩率的变化趋势与摄食等级的变化趋势呈显著的负相关。在月相的影响下,离朔日三四天之前,手钓产量呈上升趋势;离望日五六天之前,手钓产量呈明显的下降趋势。  相似文献   
165.
INTRODUCTIONInmoststudies,growthrateoffishwasfoundtodecreasewithincreasingdensity ,especiallywhenthedensitywasaboveacriticalpoint (RefstieandKittlesin ,1 976;Refstie,1 977;Trzebia towskietal.,1 981 ;VijayanandLeatherland ,1 988) .However,inacold watercarnivorousfish ,theA…  相似文献   
166.
几种网络体系结构中数据包的效率比较分析   总被引:1,自引:0,他引:1  
介绍了一种新型网络体系结构SUNA,并将它的数据包与其它两种层次型网络体系结构中的数据包进行了组成和效率上的比较分析。说明了在这方面,SUNA的数据处理效率的优势。  相似文献   
167.
Fourteen popular, representative infiltration models, some physically based, some semi‐empirical and some empirical, were selected for a comparative evaluation. Using the Nash and Sutcliffe efficiency criterion, the models were evaluated and compared for 243 sets of infiltration data collected from field and laboratory tests conducted in India and the USA on soils ranging from coarse sand to fine clay. Based on a relative grading scale, the semi‐empirical Singh–Yu general model, Holtan model and Horton model were graded respectively as 6·52, 5·57 and 5·48 out of 10. The empirical Huggins and Monke model, modified Kostiakov and Kostiakov model were graded as 5·57, 5·30 and 5·22, respectively. The physically based non‐linear and linear models of Smith–Parlange were graded as 5·48 and 5·22, respectively. Other models were ranked lower than these models. All the models generally performed poorly in field tests on Georgia's sandy soils, except the Robertsdale loamy sand. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
168.
Linear system theory can be used to model and predict watertable responses to precipitation inputs in an artificially drained field. The response function is mathematically equivalent to the Unit Hydrograph concept familiar to hydrologists. This paper shows that it is possible to derive such response functions, and comments on the problems encountered in their derivation. Response functions for two contrasted sites are presented, and the possibilities for their use discussed.  相似文献   
169.
分析了技术要素按贡献参与分配的基本依据和存在问题 ,提出了技术要素按贡献参与分配的建议 :1.在企业分配领域 ,鼓励技术要素以多种形式参与收益分配 ,鼓励体制创新 ,推进技术股份化。 2 .在政府分配领域 ,政府财政科技投入比例与其科技发展对经济贡献增长率挂钩 ,科技财税政策与产业政策、税源经济吻合 ,营造科技奖励的软环境。 3.在社会分配领域 ,充分发挥技术评估部门和行业管理部门的作用 ,对进入技术市场的技术的成熟度和科技含量进行有效的测试和监管 ,保证技术商品的品质 ;技术交易当事人应具诚信态度和法制观念 ;重视中介的作用 ,把技术市场搞活。  相似文献   
170.
This paper attempts to explore the temporal and spatial nature of the marginal revenue of land, total factor productivity (TFP) change and its three components: technical change (TC), technical efficiency change (TEC) and scale efficiency change (SEC) as seen in Chinese agricultural production from 1995 to 1999. Based on county-level data, the study utilized both stochastic frontier and mapping analyses methods. The results show that growth in the marginal revenue of land was diverse across various regions, where most gain occurred in eastern coastal zone, while loss was in Northwest and North China. China has experienced moderate decreases in annual TFP change (-0.26%) with considerable regional variations. Specifically, the administrative intervention in grain production and the deterioration of the agricultural technology diffusion system led to a moderate drop in annual TFP change. County-level mapping analyses took into account interregional variances in TFP and its components. Regarding components of TFP, TEC differences explain the majority of regional dispersions in TFP. As developed areas in China, the Huang-Huai-Hai region and the Beijing-Tianjin-Tangshan economic zone face the challenges of land conversion and grain security amidst the process of urbanization.  相似文献   
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