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131.
Despite widespread global efforts to promote clean cookstoves to achieve improvements in air and forest quality, and to reduce global climate change, surprisingly little is known about the degree to which these actually reduce biomass fuel consumption in real-world settings. Using data from in-house weighing of fuel conducted in rural India, we examine the impact of cleaner cookstoves ⿿ most of which are LPG stoves ⿿ on three key outcomes related to solid fuel use. Our results suggest that using a clean cookstove is associated with daily reductions of about 4.5 kg of biomass fuel, 160 fewer minutes cooking on traditional stoves, and 105 fewer minutes collecting biomass fuels. These findings of substantial savings are robust to the use of estimators with varying levels of control for selection, and to alternative data obtained from household self-reports. Our results support the idea that efforts to promote clean stoves among poor rural households can reduce solid fuel use and cooking time, and that rebound effects toward greater amounts of cooking on multiple stoves are not sufficient to eliminate these gains. We also find, however, that households who have greater wealth, fewer members, are in less marginalized groups, and practice other health-averting behaviors, are more likely to use these cleaner stoves, which suggests that socio-economic status plays an important role in determining who benefits from such technologies. Future efforts to capture social benefits must therefore consider how to promote the use of alternative technologies by poor households, given that these households are least likely to own clean stoves.  相似文献   
132.
田辰洋 《价值工程》2015,(12):164-167
本文主要分析了高速铁路在不同的供电方式下,容易出现的问题及产生的影响,在此基础上提出了解决的措施和建议,希望通过相关的改进措施达到更好地保护铁路沿线人员和设备安全的目的。  相似文献   
133.
刘安兵 《价值工程》2014,(32):48-49
本文对静电的形成原因进行简单讲述,并列举在民航客机中某些部位容易形成静电和该部位中静电的负作用,我们在工作中应如何预防静电的聚集和释放静电。  相似文献   
134.
Modern tools for cost-effective conservation reserve site planning require the planner to have information about spatial distributions of conservation costs and benefits. Climate change creates unprecedented uncertainty about future land values and species habitat ranges, such that conservation scientists cannot map costs and benefits with certainty anymore. This paper contributes to the literature on the economics of conservation in the face of climate change uncertainty. It advances a new method for using modern portfolio theory to choose lands to protect that yield total conservation returns with less uncertainty. It explores the implications for portfolio recommendations of variation in the correlations between ecological and land-value responses to climate change. It also tests the robustness of the method to shortcuts that might be taken to simplify analysis, identifying problems that arise if conservation costs are ignored in portfolio analysis and demonstrating when portfolio recommendations are sensitive to how ecological benefits are quantified.  相似文献   
135.
近年来,国内学者对高校贯彻实践党的群众路线的研究主要侧重于现状分析、意义论证、理念定位和对策探索等方面;对于高校如何结合新的形势实践群众路线,持续深入地开展党的群众路线教育实践活动等问题研究得较少,有待继续深入.  相似文献   
136.
通过文献资料、实地考察、专家访问等方法对我国大学生速度赛马骑师选材指标体系进行研究;为保证大学生速度赛马骑师成才的比例,促进其职业的快速发展,需要在选材时从大学生的身体形态、身体素质、身体机能、运动心理等多方面入手,科学合理地挑选出优秀的速度赛马骑师。速度赛马骑师选材指标的构建可以为赛马业大学生骑师选材提供科学指导,增加选材的确定性和可靠性。  相似文献   
137.
As there are various risks of failure when Web services are deployed in unreliable environment, the execution of a composite Web service (CWS) requires the transaction mechanism to guarantee its reliable execution. However, the existing service selection approaches consider QoS and transaction separately and have not considered that transactional properties may affect the QoS such as the execution time of a CWS. This work addresses the importance of considering transactional properties and how the transactional properties affect the QoS simultaneously in the process of service selection by a QoS-aware and transactional-aware selection approach. First, a performance evaluation method is proposed to calculate the execution time of a transactional CWS. Then, a genetic algorithm based approach, which takes into account the execution time, price, transactional property and successful execution rate of CWS, is presented to achieve global optimisation service selection. Finally, experimental results show the efficiency and effectiveness of the approach.  相似文献   
138.
139.
We analyze a dynamic market for lemons in which the quality of the good is endogenously determined by the seller. Potential buyers sequentially submit offers to one seller. The seller can make an investment that determines the quality of the item at the beginning of the game, which is unobservable to buyers. At the interim stage of the game, the information and payoff structures are the same as in the market for lemons. Our main result is that the possibility of trade does not create any efficiency gain if (i) the common discounting is low, and (ii) the static incentive constraints preclude the mutually agreeable ex-ante contract under which the trade happens with probability one. Our result does not depend on whether the offers by buyers are private or public.  相似文献   
140.
This study considers risky investment projects under adverse selection and examines optimal penalties for erroneous auditing reports to maximize social welfare. These penalties give firms an incentive to choose accounting policies that maximize social welfare. We characterize the optimal penalties such that efficient firms choose an aggressive accounting policy and inefficient firms choose a conservative accounting policy.  相似文献   
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