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1.
马玲 《石油工业技术监督》2005,21(9):12-14
介绍了燃料乙醇仿真系统软、硬件的结构,着重阐明了它的设计思想和技术特色;标准、适用、灵活是该系统的最重要的特点;实现了全流程的仿真;该系统既可用于培训,还可用于运行指导. 相似文献
2.
We present the results of flight simulator experiments (60 runs) with randomly selected airline pilots under realistic operational conditions and discuss them in light of current fuel regulations and potential fuel starvation. The experiments were conducted to assess flight crew performance in handling complex technical malfunctions including decision-making in fourth-generation jet aircraft. Our analysis shows that the current fuel requirements of the European Aviation Safety Agency (EASA) are not sufficient to guarantee the safety target of the Advisory Council for Aviation Research and Innovation in Europe (ACARE), which is less than one accident in 10 million flights. To comply with this safety target, we recommend increasing the Final Reserve Fuel from 30 min to 45 min for jet aircraft. The minimum dispatched fuel upon landing should be at least 1 h. 相似文献
3.
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
4.
采用全生命周期评价方法,对菜籽油制生物柴油的二氧化碳排放量和经济性进行了评估,旨在说明用菜籽油生产生物柴油对环境的影响及其经济价值。结果表明:在用菜籽油生产生物柴油的全生命周期过程中,排放入大气中的二氧化碳量远低于从大气中吸收的二氧化碳量,油菜籽制生物柴油是一种环境友好的燃料;就经济性而言,菜籽油制生物柴油的生产成本较高,每吨约高出0#柴油3178.2元,生物柴油的商业化应用尚需等待原料成本的降低。 相似文献
5.
作为得自于动植物油脂的脂肪酸甲酯,即所谓的生物柴油是一种来自于动物或植物的可再生燃料资源。目前在世界各国正掀起一开发利用生物柴油资源的热潮。对目前国际上生物柴油开发和利用现状进行了介绍,同时也对中国生物柴油的开发和应注意的问题进行了阐述。 相似文献
6.
中国旅游产业对国民经济的贡献研究 总被引:1,自引:0,他引:1
文章采用旅游增加值剥离测算法估算2000~2008年中国大陆31个省级单位的旅游产业增加值,并测量旅游产业增加值对国民经济的贡献率和拉动幅度,旨在分析旅游产业在国民经济中的地位。结论有三:第一,我国旅游产业以高于国内生产总值的增长速度快速成长,波动较大且存在地区差异;第二,旅游产业的发展与国民经济的整体发展水平密切相关,在以旅游产业作为先导产业的省份中,旅游产业对国民经济的拉动作用较为显著;第三,我国大部分地区的旅游产业对GDP贡献率主要集中在3%~8%,而拉动系数则保持在0.5至1.5个百分点之间。 相似文献
7.
8.
《Futures》2017
Climate projections are based on emission scenarios. The emission scenarios used by the IPCC and by mainstream climate scientists are largely derived from the predicted demand for fossil fuels, and in our view take insufficient consideration of the constrained emissions that are likely due to the depletion of these fuels. This paper, by contrast, takes a supply-side view of CO2 emission, and generates two supply-driven emission scenarios based on a comprehensive investigation of likely long-term pathways of fossil fuel production drawn from peer-reviewed literature published since 2000. The potential rapid increases in the supply of the non-conventional fossil fuels are also investigated. Climate projections calculated in this paper indicate that the future atmospheric CO2 concentration will not exceed 610 ppm in this century; and that the increase in global surface temperature will be lower than 2.6 °C compared to pre-industrial level even if there is a significant increase in the production of non-conventional fossil fuels. Our results indicate therefore that the IPCC’s climate projections overestimate the upper-bound of climate change. Furthermore, this paper shows that different production pathways of fossil fuels use, and different climate models, are the two main reasons for the significant differences in current literature on the topic. 相似文献
9.
Sustainable Jet Fuel (SJF) represents an important component of the airline industry's strategy to simultaneously reduce GHG emissions while meeting a growing demand for international air travel. SJFs also have the potential to provide fuel supply diversification and security, enhance fuel price stability and provide regional/rural economic development benefits. This paper measures and ranks perceived drivers and barriers to an economically viable SJF industry in a unique U.S. region, the U.S. Pacific Northwest (PNW), through personal interviews with key aviation fuel supply chain stakeholders conducted from June to September 2015. In addition to providing a fertile arena for this first effort to systematically assess these drivers and barriers, the U.S. PNW is unique due to the region's long strategic focus on aviation innovation and its importance to the regional economy, the seminal efforts in the region to outline a path forward on SJF beginning in 2010, and the relatively small population spread over a large geographic area with a limited number of “hub” airport nodes which geographically concentrates aviation fuel demand and distribution. Nineteen stakeholder interviewees acknowledge that, in order for regional SJF adoption-diffusion to occur, airline jet fuel buyers must drive the process, particularly as they deal with greenhouse gas (GHG) emission issues and related policy considerations. Important perceived barriers to SJF industry scale-up in the U.S. PNW include the high production costs of SJF and related issues, such as fuel logistics and quality control in the transport, storage, and blending of SJFs. Perceptions around chain-of-custody issues, such as blending, tracking, and crediting of SJFs and future SJF market share projections for the year 2030 were also examined. Incorporating stakeholder input into discussions about adding blended SJF into the U.S. aviation fuel supply provides needed insight for the biofuels industry, policymakers, and researchers. 相似文献
10.
本文通过构建简单的总供给一总需求模型,分析石油数量调控政策、潜在产出水平与均衡价格上涨之间的数理逻辑关系,进而间接得到液态生物质燃料适度规模问题的一般分析框架,为进一步的定量分析打下坚实基础。研究结果表明:为达到潜在产出水平和一定的价格上涨水平,不同的现实条件要求政府实行不同的石油数量调控政策。 相似文献