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91.
Many developing countries such as Turkey are still making an effort on building an infrastructure for waste of electrical and electronic equipment (WEEE) reverse logistic network design (RLND) processes. It is obvious that policies/laws/regulations related to WEEE management provide a sustainable framework for implementation in the RLND. The question is here: Does the implementation of WEEE directives make sense in terms of reducing the total cost of the network in the long term? This study aims to compare regulatory and non-regulatory situations of WEEE RLND in developing countries by formulating two models named as ‘regulatory’ and ‘non-regulatory’. Model 1 is considered as sustainable with economic, environmental and social goals, and the quotas imposed by the environmental directive are taken into consideration as the data of product return amount. In Model 2, only economic goal is considered, and product return amount is forecasted using Artificial Neural Network (ANN). A case study is conducted in a recycling company in order to evaluate performance of the proposed models. This study contributes to the relevant literature by (1) comparing the regulatory and non-regulatory situations RL models explicitly and (2) proposing ANN model to forecast EEE product return or WEEE quantity for non-regulatory situation.  相似文献   
92.
It has been suggested in recent years that developing countries need not pass through the dirty stages of industrial growth that marred the past of today's developed countries. Instead, they may be able to bypass these by leapfrogging straight to modern, clean technologies as an integral part of capacity addition. This article critically reviews existing approaches to leapfrogging. It argues that they are not only characterized by considerable ambiguity, but also based on an incomplete understanding of the technological and policy requirements of cleaner industrialization. Consequently, the article goes on to offer a number of suggestions as to how current approaches might be advanced so as to better meet the challenge of leapfrogging. Amongst these suggestions is greater clarification of the specific targets for leapfrogging and policy intervention to accelerate the development of technological capabilities needed to select, absorb and innovate leapfrog technologies.  相似文献   
93.
目前我国钾矿资源紧缺,生产的钾肥不足,因而农业严重缺钾。为了改变这种局面,本文从战略的高度提出了对策:理顺和拓宽我国找钾新思路,扩大找钾领域,充分发挥和利用国内外两种资源、两个市场的互为补充举措,投资开发周边邻国钾矿资源和开辟国内液态钾矿-富钾卤水的勘查开发,是解决我国钾矿资源短缺的两个重要的有效途径。  相似文献   
94.
This paper discusses the conceptual basis for linking development policies and climate change adaptation and mitigation and suggests an analytical approach that can be applied to studies in developing countries. The approach is centred on a broad set of policy evaluation criteria that merge traditional economic and sectoral goals and broader social issues related to health and income distribution. The approach is inspired by institutional economics and development paradigms that emphasise human wellbeing, resource access, empowerment, and the arrived freedoms. It is outlined how indicators of wellbeing can be used to assess policies that integrate development and climate change policy objectives, and this approach is discussed in comparison with other work that rather have been inspired by sustainable development aspects of manmade, natural, and social capital. The experiences and results from case studies of development and climate that have done a first attempt to use human wellbeing indicators are reported and discussed. The studies include work from India, China, South Africa, Brazil, Bangladesh, and Senegal. A number of policy examples in the energy-, food-, and water sectors in these studies have shown up to demonstrate numerous linkages between development policies and climate change. Various analytical tools have been used in the studies including quantitative and qualitative scenario work as well as detailed micro-based analysis. The methodological conclusion that can be drawn from these studies, is that it is possible to apply wellbeing indicators to the more detailed policy assessment, but a link to more general national and regional scenario work is not yet established.  相似文献   
95.
The principles of hydrocarbon exploration and production provide well-established and tested principles and technologies to investigate storage of fluids in the subsurface. CO2 can be stored in the subsurface using settings of: (A) thick permeable coal seams; (B) depleted oil and gas fields; (C) saline aquifers of regional extent, with an overlying seal. The North Sea Sleipner project shows that CO2 can be injected into the pore space of deep geological aquifers deeper than 800 m at 1 Mt/yr, using established technology. Suitable sediment sequences of saline aquifers exist in all hydrocarbon-producing areas, are volumetrically much larger than exploited oil and gas fields, and hold the potential to easily store all worldwide CO2 emissions until 2050. Geological principles are established to assess entire continents for candidate sites of CO2 storage. This shows that opportunity may be widespread, but needs more specific local investigations. Onshore sub-Saharan Africa is considered the most problematic region – but even here there are potentially viable sediment sequences. No demonstration projects currently exist for CO2 capture and storage using small-scale onshore facilities. A simple estimate, assuming CO2 value of $20 per ton, suggests that single boreholes onshore may be viable over 20 years with supply rates of 100,000 ton CO2 per year. In principle, atmospheric CO2 could be captured by cultivated biomass, and co-fired in existing power stations. Or energy crops could be grown, CO2 to be used, and stored deep below ground, in a country distant from an original fossil-fuel CO2 emission site.  相似文献   
96.
本文根据联合国粮农组织(FAO)提出的3大目标,以及关于本世纪末实现小康目标的要求,阐述了常熟市农业可持续发展的对策,以及克服制约当地农业可持续发展的主导因素而采取的措施和取得的成效.  相似文献   
97.
Livestock production and the use of synthetic fertilizer are responsible for about half of the global emission of NH3. Depending on the animal category between 10 and 36% of the N in animal excreta is lost as NH3. The current annual NH3 emission in developing countries of 15 million ton N accounts for of the global emission from animal excreta. In addition, 7.2 million tons NH3N of synthetic N fertilizers are lost as NH3 in developing countries. This is 80% of the global NH3 emission from synthetic fertilizer's use. Along with human population increase and economic growth, livestock production in developing countries may even increase by a factor of 3 between now and 2025. The net result of rapid increase of livestock production combined with higher efficiency is an increase in NH3 emissions of only 60% from 15 to 24 million tons NH3N between 1990 and 2025 in developing countries. Livestock production is an important consumer of feedstuffs, mainly cereals, thereby inducing additional demand for synthetic fertilizers. Despite the projected major increase of synthetic fertilizer use from 42 to 106 million ton N between 1990 and 2025, the NH3 loss in developing countries may decrease if a shift towards other fertilizer types, that are less vulnerable to NH3 volatilization, is realized. According to the scenario, the total emission of NH3 associated with food production in developing countries will increase from 22 to 30 million ton N yr−1 between 1990 and 2025. Although the NH3 emission increases more slowly than food production, in particular, animal production may show geographic concentration in certain regions, which may lead to high local emission densities and associated environmental problems.  相似文献   
98.
国家作出了污染物总量控制的决策,它要求必须建立完善的污染物控制体系。文章结合了发达国家环境管理的成功经验,以框架方式论述了大气固定污染源的控制体制和支持系统。对固定源的管理体制论述包括环境标准、最佳控制技术、最大限度削减排放的原则、排污许可证制度、宽限期、公众参与、监测、处罚等项;支持系统论述包括管理人员、法规与标准、技术支持等项。  相似文献   
99.
论农村居民点用地混合利用的研究框架   总被引:1,自引:0,他引:1  
土地混合利用倡导不同使用性质/功能用地的混合布局,是提高经济发展活力与土地利用集约度的重要途径。当前,土地混合利用主要应用于城市用地演变与规划实践领域,伴随着城乡互动加剧,城乡界限趋于模糊,经济发达地区的农村居民点用地内部结构与功能逐渐多样化,也呈现显著的混合利用特征。基于此,尝试将土地混合利用应用到农村居民点用地演变与规划中,在回顾土地混合利用理论及其应用的基础上,按照“内涵特征—定量测度—驱动机理—实践路径”的逻辑思路,对经济发达地区的农村居民点用地混合利用进行系统解析,并以天津都市郊区的姚村为例实证本文提出的研究框架,在理论上丰富农村居民点用地转型的内容与方法,在实践中为编制村庄规划、助推乡村振兴提供科学支撑。  相似文献   
100.
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