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排序方式: 共有419条查询结果,搜索用时 876 毫秒
131.
车站信号表示盘系统是车站调度人员进行作业调度的重要设备.本单位和西安铁路信号工厂联合开发了一种新型计算机联锁表示盘系统,介绍了该表示盘系统的硬件结构和软件结构,对CAD软件中涉及到的搜索算法进行了详细的阐述.该系统较好地满足了现场调度人员的要求,已通过有关电务部门的鉴定. 相似文献
132.
Despite the current interest in using fuel taxes as an instrument for climate policy, there has been little study of current automotive fuel tax regimes. We expand on two earlier cross-sectional studies on why fuel taxes differ across countries by using OECD panel data and employing heterogeneous panel cointegration and long-run panel Granger-causality techniques. We confirm some of those earlier studies’ conclusions. Further, we find that governments that rely on consumption-based taxes for revenues will have higher gasoline tax rates (than governments that rely on income and wealth/property-based taxes). But more significantly, we determine that higher gasoline demand among consumers “causes” democratic governments to set lower gasoline taxes—a finding with important implications for today’s climate/energy policy debate. 相似文献
133.
Aviation is a fast growing sector with increasing environmental concerns linked to aircraft emissions at airports and noise nuisance. This paper investigates the factors affecting the annual environmental effects produced by a national aviation system. The environmental effects are computed using certification data for each aircraft-engine combination. Moreover, we also take into account for the amount of environmental effects that is internalized at the airport, mainly through noise regulation. We study a dataset covering information on Italian airports during the period 1999–2008. We show that a 1% increase in airport’s yearly movements yields a 1.05% increase in environmental effects, a 1% in aircraft size (measured in MTOW) gives rise to a 1.8% increase and a 1% increase in aircraft age generates a 0.69% increase in environmental effects. Similar results but with smaller magnitudes are observed if airport internalization is considered. Our policy implications are that the tariff internalizing the total amount of externality is about euro 180 per flight, while the tariff limiting only pollution is about euro 60 and the one reducing noise is about euro 110. Moreover, our airport examples show that managers should prefer to address additional capacity by increasing frequency rather than aircraft size, since the former strategy is more environmental friendly. 相似文献
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A spatial and temporal analysis of travel diary data collected during the State of California Telecommuting Pilot Project is performed to determine the impacts of telecommuting on household travel behavior. The analysis is based on geocoded trip data where missing trips and trip attributes have been augmented to the extent possible. The results confirm the earlier finding that the Pilot Project telecommuters substantially reduced travel; on telecommuting days, the telecommuters made virtually no commute trips, reduced peak-period trips by 60%, total distance traveled by 75%, and freeway miles by 90%. The spatial analysis of the trip records has shown that the telecommuters chose non-work destinations that are closer to home; they exhibited contracted action spaces after the introduction of telecommuting. Importantly, this contraction took place on both telecommuting days and commuting days. The telecommuters distributed their trips, over the day and avoided peak-period travel on telecommuting days. Non-work trips, however, show similar patterns of temporal distribution on telecommuting days and commuting days. Non-work trips continued to be made during the lunch period and late afternoon and evening hours. 相似文献
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在悬索桥中再度研究设计应用板式加劲梁 总被引:1,自引:1,他引:0
根据悬索桥的基础理论及其加劲梁基本结构形式的发展演变和设计流派的研究,结合美国塔科玛桥板式加劲梁悬索桥的风毁工程实例,着重对板式加劲梁结构的抗风稳定性和工程措施再度研究分析。在此基础上,结合实桥设计将研究成果分别应用于预应力板式加劲梁悬索桥和钢板式加劲梁悬索 相似文献
139.
在机车的显示与诊断系统中,使用高分辨率平板显示器已成为一种趋势。本文详细介绍了等离子体显示屏及其驱动系统的工作原理。 相似文献
140.
针对PZXI型智能电源屏存在的交流模块故障时不能自动切换,无法给出正确故障表示的设计缺陷,进行改进。 相似文献