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61.
Carsten Helm 《Environmental and Resource Economics》1998,12(2):185-201
The complexities of international environmental problems are only poorly understood. Hence, decision makers have to negotiate about abatement measures even though they do not know the 'true' model of the ecological system and have only a rough idea about the costs and benefits of their action. It will be analysed to what extent this kind of 'model uncertainty' – where players do not only have incomplete information about the payoff functions of the other players, but also about their own payoff function – affects the prospects of international cooperation. Using a simple game-theoretic model, it is shown how countries can use the veil of uncertainty to hide their distributional interests. The arguments are based on a deviation from the common prior assumption, which seems particularly questionable in a setting comprising various countries with different cultural and scientific backgrounds. Finally the model will prove useful to quantitatively and qualitatively illustrate the central role of model uncertainty in the negotiations of the first Sulphur Protocol signed to combat transboundary acidification. 相似文献
62.
为了解决卫星数据分发系统中雨衰对下行链路的异构性影响,建立了基于再生转发器和多波束技术的卫星数据分发系统简化模型,提出了采用星上自适应分组级FEC(Forward Error Control)的下行链路差错控制方法,针对下行链路的降雨等级自适应选择纠错码率,在不占用上行共享链路的情况下,实现对下行链路差错控制的动态调整,给出了采用RSE码的星上自适应FEC的算法公式,通过MATLAB软件和端到端的FEC技术进行了仿真比较分析,结果表明,当下行链路降雨率小于50%时,网络吞吐率可提高12%~25%。该策略可以为多波束宽带卫星数据分发系统的设计提供参考。 相似文献
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绿色建筑是可持续发展的产物,在节水方面,其倡导使用非传统水源和水资源的循环利用。发展绿色建筑有利于缓解水资源短缺和城市用水量不断增加的矛盾。绿色建筑的水系统及雨水资源利用技术,将绿色建筑及雨水利用结合起来,对生态和可持续发展有重要意义。 相似文献
65.
Phytoplankton as biomonitors: A study of Museum Lake in Government Botanical Garden and Museum,Thiruvananthapuram, Kerala India 下载免费PDF全文
An assessment of the pollution status of Museum Lake in the Thiruvananthapuram Botanical Garden and Museum was conducted. Analysis of different community structures of the planktonic taxa in the lake revealed it is organically polluted, attributable to the organic litter from riparian vegetation. A total of 30 most pollution‐tolerant phytoplankton genera and 24 pollution‐tolerant species were identified. Pollution‐tolerant phytoplankton genera in the lake included Chlorophyceae, Bacillariophyceae, Cyanophyceae and Euglenophyceae. Scenedesmus, Pinnularia, Euglena, Ankistrodesmus, Closterium, Crucigenia, Kirchneriella, Merismopedia and Oscillatoria were some of the phytoplankton pollution tolerant genera whereas, Nitzschia palea, Synedra acus, Scenedesmus quadricauda, Pandorina morum and Trachelomonas volvocina were some of the pollution tolerant species noted. Excessive nutrient loading from the surrounding area is definitely degrading the quality of this urban lake ecosystem. Detailed information regarding the pollution status of a waterbody is very important in this regard, noting it ultimately assists in undertaking proper management of a waterbody. The Palmer Algal Index score for Museum Lake was 37, indicating it is highly organic enriched. The results of different algal indices (e.g. Chlorophycean Index; Nygaard Index) indicated a eutrophic condition for Museum Lake, being attributed to its increased organic enrichment. Canonical correspondence analysis between environmental variables and the microalgal bioindicators also highlighted the influence of the physical and chemical parameters on phytoplankton abundance and distribution in Museum Lake. 相似文献
66.
This paper considers an acid rain differential game. Countries emit sulphur which is partly transferred to other countries. Depositions above critical loads ultimately destroy the soil. Countries face a trade-off between the costs of emission reductions and the damage to the soil due to the depletion of the acid buffers. Because of the transboundary externalities the outcome will depend on whether the countries cooperate or not. This paper presents the cooperative outcome and the open-loop and Markov-perfect Nash equilibria of the acid rain differential game. It will be shown that the depositions always converge to the critical loads but the steady-state levels of the buffer stocks differ. The theory is used to analyse the acid rain differential game for sulphur between Great Britain and Ireland. Finally, some results are given for the whole of Europe. 相似文献
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在全面了解西安市水资源经济系统现状及其内部结构的基础上,结合西安市现状,运用系统动力学方法,构建了西安市水资源经济系统SD模型,预测了西安市雨水资源利用的前景和经济发展趋势。结果表明:如果西安市按照现有模式发展,则未来经济会受到水资源匮乏问题的严重制约;在其他条件不变的情况下,提高农业用水比例、雨水资源投资比例及雨水资源价值系数,从价格和数量两方面促进雨水资源综合利用,可以在增加城市供水量的同时促进经济发展,实现水资源经济协调可持续发展。 相似文献
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