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The paper presents one of the initial steps in the evaluation process towards possible implementation of an innovative taxiway intersection design at Munich Airport apron. A roundabout is proposed as a potential solution for the 12-line intersection area expected at redesigned Apron 3. Although it is a common solution used in road transport for complex intersections, the roundabout has never previously been used for airport surface operations nor has its possible use been considered or analyzed. The paper presents preliminary design and operations concepts of the apron roundabout, followed by its capacity evaluation under Munich Airport operating conditions. The aim was to analyze whether a roundabout is suitable to replace a conventional intersection, in terms of capacity. 相似文献
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调查发现视屏显示终端操作者主诉有神经衰弱、易感冒、眼和肌肉骨骼不适。客观呈现眼视力下降,颈肩腕肌肉压痛。生殖系统调查有月经异常和先兆流产、自发性流产率增高。研究揭示,视屏显示终端室内外温差大,空气阴离子减少,臭氧很少,固定式的桌椅和不良的坐姿等是影响视屏显示终端操作者健康的主要因素。符合卫生标准的环境和工效学原则的规范化操作,可保护视屏显示终端操作者的健康。工间休息能使视力恢复,不良的健康反应得以消除。 相似文献
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田少民 《筑路机械与施工机械化》1992,9(2):17-20
液力传动工程机械的整机出力不足时,要判明其原因是发动机输出功率不足,还是传动系有故障,这是现场经常遇到的一个问题。本文介绍的本机现场失速性能测定法,使用一只光电转速表即可评定原机稳定工况下的发动机功率,是一种判断机械出力不足故障原因的有效方法. 相似文献
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论述轨道交通运营客流数据对城市轨道交通的规划设计和运营管理的重要作用,讨论城市轨道交通运营客流数据的用途,主要包括票务清分、统计规律、调配运力、辅助预警等。结合客流分析过程中数据采集的时效性、准确性和完备性,针对数据分析方法和标准等方面的不同缺陷进行研究,归纳出产生的原因主要来自于自动售检票(AFC)系统、运营管理、分析方法和标准等方面。提出应对缺陷的措施包括统一数据平台和标准、提高AFC系统可靠性、改进运营管理手段、增加数据采集手段、改进数据分析方法和指标等。通过这项研究,以期保障城市轨道交通运营安全,并提高运营效益。 相似文献
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罗慧刚 《铁道标准设计通讯》2019,(3):90-95
我国快速发展的经济对铁路运输能力的要求不断提高,既有铁路重载扩能运输改造进程不断推进,随之提高的列车轴重必然会降低既有铁路桥梁的活载储备量,从而导致T梁的整体刚度和耐久性下降。通过对不同跨径桥梁活载储备量的计算分析,进而选取跨度12 m混凝土T梁作为研究对象进行静力适应性分析,对梁体跨中截面主筋应力、梁体跨中截面上翼缘混凝土压应力及梁体跨中底板裂缝宽度进行检算;并且建立动力有限元模型,分析不同列车荷载作用对跨中横向加速度及横向振幅的影响规律,并与试验实测结果进行对比分析。研究结果表明:在270 k N和300 k N轴重重载列车作用下,梁体受拉钢筋最底部主筋应力均超过容许值;结构动力响应随着车辆轴重增大而增大; 12 m跨低高度简支钢筋混凝土梁横向动力适应性优于普通高度简支梁,两者均满足开行大轴重重载货车要求。 相似文献
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结合现场实际情况,在系统层面对于全电子计算机联锁系统进行更加客观准确的运营安全评估,综合考虑系统的风险严重度及风险可能性,提出一种基于最优组合权重计算法的云模型安全评估方法。首先从人员、设备、环境、管理、维修5个方面建立安全风险评估体系,在专家评估的基础上运用最优组合权重法计算体系中的底层指标权重,再将权重代入评估云模型的计算中,分别得到系统的风险可能性和风险严重度评估值,综合得出系统的运营安全风险容忍等级。将该方法引入全电子联锁系统的运营安全评估中,通过对实际数据的计算,证实该方法能够克服以往评估方法的主观性和片面性,使得到的结果更加准确和直观,实现真正意义上的“综合”评估。 相似文献
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杨立彬 《铁路通信信号工程技术》2010,7(6):32-33
主要讨论在联锁系统出现异常的情况下,控显子系统通过增加逻辑判断,帮助值班人员快速定位故障,并提出了初步的实现思想。 相似文献
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The increasing global warming is most likely to affect the magnitude and pattern of wind at a regional level and such an effect may or not follow the trend predicted at the global scale. Regional level exercises are therefore necessary while making decisions related to engineering infrastructure. In this paper an attempt is made to know the extent of change in design as well as operational wind conditions at two offshore locations along the west coast of India. The design wind speeds with return periods of 10, 50 and 100 years derived for two 30-year time slices in the past and future are compared. In two separate exercises the past and future wind at the local level is simulated by empirical downscaling as well as by interpolation of the general circulation model (GCM) output. Both sets of past and future data are fitted to the Generalized Pareto as well as Weibull distributions using the peak over threshold method to extract long term wind speeds with a specified return. It is noticed that at the given locations the operational and design wind may undergo an increase of around 11%–14% when no downscaling is adopted and 14%–17% when the GCM data are downscaled. Although these figures may suffer from a certain level of statistical uncertainty the study points out to take a relook into the safety margins kept in the design and operation of ocean structures in the light of global warming. 相似文献