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国外通用航空运行及未来发展趋势 总被引:2,自引:0,他引:2
<正>在欧、美国家除公共运输飞机和军用飞机 外,其他飞行器均属通用航空范畴。通用航空飞 行器作为生产工具可进行航空作业,作为运输 工具可进行客、货、邮件的航空运输,其应用主 要有:公务飞行、训练飞行、农林业和工业航空 作业飞行、通勤飞行、出租飞行、私人飞行以及 其他的飞行,概括地说,通用航空由航空作业和 通用航空运行两个部分组成。在此,仅就国外的 通用航空运行部分及21世纪发展先进的通用 航空运输系统作些粗浅介绍。 一、西方国家的通用航空运行 目前,在欧、美国家普遍采用航空作业运行 以外的通用航空运行模式,使用通用航空飞机 相似文献
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在航班运行过程中,飞行员作为飞行任务的执行者,是保障飞行安全的最后一道防线。但如今飞机自动化程度越来越高、运行环境逐渐复杂,为了有效提高飞行员的综合素质,更好地保障飞行安全、提升飞行品质,通过查阅文献、问卷调查、结构性访谈等,对飞行学员的核心胜任力进行了深入探究,最终确定了飞行学员的八大核心胜任力,19项二级评价指标。利用SPSS分析、AHP层次分析和灰色关联法,最终构建出飞行学员核心胜任力评价模型,可以作为飞行学员进行准确的自我定位和不断提升自我的有效工具,更为民航院校对飞行学员的核心胜任力进行全面的评估分析提供了有力的支持。 相似文献
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文章以北京地铁15号线南法信站-石门站盾构区间右线为工程背景,分析了选择加压开舱技术的理由,提出加压开舱的气压、泥膜和人员等为控制重点要素;论述了加压开舱的原理和工作流程,即根据承压水细中砂地层特点配置适合的泥浆,运用静止土压力理论并考虑土压和水压设定开舱气压,经过一定的流程形成掌子面及周边密封的泥漠,通过在人舱内一定速率的加压和减压,最终完成加压开舱检查刀盘的工作.实践证明,工程中制作的泥漠及设定的压力,有效地控制了土舱内的压力,保证了掌子面和地面的稳定,并且人员的选择、工艺的安排,在很大程度上提高了工作效率、缩短了工期、节省了成本,显现了加压开舱的优点. 相似文献
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在复合地层中土压平衡盾构机开舱是一项比较危险的作业。文章系统地介绍了开舱作业风险源,并提出了相关的风险控制方法;分析了深圳地区的地质、水文情况对开舱条件的适宜性,以及对各种条件下开舱点选择的风险防范;最后介绍了深圳地铁2222标侨-香区间的7次开舱经验,并对其开舱进行分类、总结。 相似文献
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列车运行阻力是影响列车能耗的主要因素,文章基于车辆运行阻力公式以及线路附加阻力公式,通过对跨座式单轨车辆运行阻力的分析及其与地铁车辆运行阻力的对比,得出跨座式单轨车辆的基本阻力与线路附加阻力关系、单轨跨座车辆与地铁车辆运行阻力的关系等特点,可为跨座式单轨交通项目的牵引能耗计算以及节能分析工作提供参考。 相似文献
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文章以深圳地铁2号线东延线2222标段工程中采用的带压开舱换刀试行方法为依托,针对NFM土压平衡盾构机的设备情况,总结出了相关的技术方案,主要包括开舱前的准备工作和带压开舱换刀作业的整个实施流程及相关技术要点。 相似文献
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Investigating the joint choice behavior of intercity transport mode and high‐speed rail cabin with a strategy map
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This paper investigates the joint choice behavior of intercity transport modes and high‐speed rail cabin class within a two‐dimensional choice structure. Although numerous studies have been conducted on the mode choice behavior, little is known about the influence of cabin class on their intercity traveling choice. Hence, this study is conducted with a revealed preference survey to investigate the intercity traveling behavior for the western corridor of Taiwan. The results of nested logit model reveal that a cabin strategy has a more significant influence on cabin choice than on mode choice. Furthermore, this study proposes a new strategy map concept to assist transport operators in defining and implementing their pricing strategies. The results suggest that to capture a higher market share, high‐speed rail operators should choose an active price reduction strategy, while bus and rail operators are advised to implement a passive price increase strategy to raise unit revenue. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Abstract The role of the railways in the air transport industry is usually limited to provision of access to airports. However, the development of high-speed rail networks and the congestion and environmental problems faced by the air transport industry suggest the railways could have a greater role in working with the airlines to provide an integrated transport service for medium-distance journeys (up to 800 km). Many air journeys involve two flights and a transfer at a hub airport. The alternative being investigated here would replace air journeys by a rail journey and a flight, and a transfer between them at the hub airport. Such integration could offer a positive alternative to aircraft on some routes and lead to railway journeys to airports becoming part of air transport services, and not only to provide access to them. Integration could therefore provide a better use of available air capacity rather than duplicating some high-speed rail routes and services. 相似文献
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To determine ways to reduce commuters’ ultrafine particle exposure, factors such as ventilation condition, mechanical airflow rate, driving speed, cabin air filter quality, and cabin air filter use are examined. The results show that the in-cabin to on-roadway ratio is reduced by 20% when the fan is set to recirculation-on versus when set to recirculation-off because fewer ultrafine particles are exchanged between the inside and outside of the cabin. Also, when the fan is set to recirculation-off, the ratio is reduced by 40% at lower mechanical airflow rates. The thickest cabin air filter resulted in a 30% in-cabin to on-roadway ratio decrease compared with the thinnest. Thus, driving conditions with the least UFP in-cabin to on-roadway ratio is when a vehicle is operating with a high efficiency cabin filter, the ventilation set to fan-on and recycling is recirculation on, and at a high ventilation airflow rate. Furthermore, recirculating in-cabin air through a high efficiency particulate air filter was found to significantly reduce in-cabin UFP exposure. 相似文献
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结合上海轨道交通网络化运营生产组织工作实际,针对轨道交通生产经营过程中的风险源,对其运营突发事件的应急处置工作进行分析和研究,从风险源分析、能力评估、组织架构及体系建设等方面着手,提出能够适应城市轨道交通网络化运营需求应急处置体系的一些设想。 相似文献
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It is widely known that emissions from aircraft engines, Auxiliary Power Units (APU) and ground handling equipment contribute to air pollution at airports. During the aircraft turnaround process, the main source of emissions is the APU. The use of the APU can be significantly reduced if the aircraft stand is equipped to supply external electrical power and pre-conditioned air to the cabin. This paper analyses the actual duration of APU and external power usage during intraday aircraft turnarounds at 125 airports during June 2015. The data is derived from flight data recording units of more than 200 short-haul, narrow-body jet aircraft, conducting some 25,195 aircraft turnarounds and thus provides the most detailed assessment of aircraft power usage available. A common practice is for the APU to be running for a short period on arrival at the stand (arrival-cycle) and then again for a short period prior to departure (departure-cycle). It is identified in this study that departure-cycle emissions are three times greater than arrival-cycle emissions. These emissions could be reduced if more accurate forecasts of departure times are available to flight crew. The provision of external ground power is found to reduce emissions by up to 47.6%. However, the study also highlights that when the source of external power is a diesel-fuelled mobile Ground Power Unit (GPU), there is a net doubling in emissions of hydrocarbons. APU usage is also observed to vary with outside air temperature (OAT) leading to possible increases in emissions of up to 6%. 相似文献
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This paper analyses how the high-speed rail construction in Northeast Japan (Tohoku) has affected total demand and interregional travel patterns. We use annual interregional passenger data from 1989 to 2012 and apply regression analysis with the demand between Tokyo and the Tohoku prefectures as the dependent variable. We distinguish particularly between the ‘Full-’ and the ‘Mini-’ Shinkansen, where the latter are branch services running with reduced speed. We find that the ‘Full-Shinkansen’ quickly increases rail and total public transport trips and generates additional rail demand year on year. The ‘Mini-Shinkansen’ impacts are less pronounced. Furthermore, our analysis shows that the Shinkansen has shifted some demand from air to rail once it started operation and increased rail share gradually. We therefore suggest that predictions of demand impacts should carefully distinguish immediate from gradual impacts. We also discuss differences in regional demand in that not all prefectures have gained equally from Shinkansen construction. 相似文献
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The objective of this study is to provide a strategic evaluation of the mitigation of CO2 emissions via modal substitution of high-speed rail for short-haul air travel on the Sydney–Melbourne, Australia city-pair from a life cycle perspective. It has been demonstrated that when considering CO2 emissions from vehicle operations, the modal shift from air to high-speed rail on this city-pair has the potential to provide a means of CO2 mitigation. However, uncertainty exists with regard to the level of mitigation potential when considering the whole-of-life performance of the systems. Given the significant difference in the infrastructure requirements between the air mode and the high-speed rail mode, this study quantifies the life cycle CO2 load attributable to each system and examines the effect on CO2 mitigation potential. The study concluded that while the inclusion of the linehaul infrastructure did increase the CO2 load associated with high-speed rail mode, it did not equate to or exceed the CO2 load per trip as experienced by the air mode. The avoided annual life cycle CO2 emission in the target year 2056 was 0.37 Mt representing an 18% reduction when compared to the air mode only on the city pair. In fact, the scenario comparison indicated that the substitution of high-speed rail for short-haul air travel on the city pair resulted in CO2 emissions avoidance throughout the longitudinal period. 相似文献
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高铁货运逐渐兴起,本文对货运动车组开行方案优化进行了研究。针对高铁运输安全、快捷、运输成本较低等特性,提出以货运动车组及客货混编动车组为主,客运动车组捎带运输为补充的开行模式,结合运输需求、线路通过能力等限条件,以运输成本最小和货主满意度最大为目标,建立多目标综合优化模型,运用线性加权组合法,以lingo软件为依托进行求解。通过算例给出具体开行方案,并对同一运输区间各种运输方式的单位成本及用时进行对比分析。结果表明,相对于传统运输方式,高铁货运综合运输成本较低,用时更短,能够兼顾运输企业与货主的双重要求;所建模型优化效果明显,可为未来货运动车组的开行提供参考。 相似文献