Implementation and application of a stochastic aircraft boarding model

The aircraft turnaround processes is mainly controlled by the ground handling, airport or airline staff, except the aircraft boarding, which is driven by the passengers’ experience and willingness or ability to follow the proposed boarding procedures. The paper uses a prior developed, calibrated, stochastic aircraft boarding model, which is applied to different boarding strategies (chronological order of passenger arrival, hand luggage handling), group constellations and innovative infrastructural changes (Flying Carpet, Side-Slip Seat, Foldable Passenger Seat). In this context, passenger boarding is assumed to be a stochastic, agent-based, forward-directed, one-dimensional and discrete process. The stochastic model covers individual passenger behavior as well as operational constraints and deviations. A comprehensive assessment using one model allows for efficient comparison of current research approaches and innovative operational solutions for efficient passenger boarding.     

Happy or liberal? Making sense of behavior in transport policy design

Appropriate microeconomic foundations of mobility are decisive for successful policy design in transportation and, in particular, for the challenge of climate change mitigation. Recent research suggests that behavior in transportation cannot be adequately represented by the standard approach of revealed preferences. Moreover, mobility choices are influenced by factors widely regarded as normatively irrelevant. Here we draw on insights from behavioral economics, psychology and welfare theory to examine how transport users make mobility decisions and when it is desirable to modify them through policy interventions. First, we explore systematically which preferences, heuristics and decision processes are relevant for mobility-specific behavior, such as mode choice. We highlight the influence of infrastructure on the formation of travel preferences. Second, we argue that the behavioral account of decision-making requires policy-makers to take a position on whether transport policies should be justified by appealing to preference satisfaction or to raising subjective well-being. This distinction matters because of the (i) influence of infrastructure on preference formation, (ii) health benefits from non-motorized mobility, (iii) negative impact of commuting on happiness and (iv) status-seeking behavior of individuals. The orthodox approach of only internalizing externalities is insufficient because it does not allow for the evaluation of these effects. Instead, our analysis suggests that transport demand modeling should consider behavioral effects explicitly.     

交通环境变化下的交通与经济互动性分析

交通和经济是区域的两大职能因素,它们是相互影响并且相互制约的。交通环境的变化将对区域经济产生重要的影响,同时经济发展也将进一步地刺激交通发展。以宜昌市为例,在分析宜昌交通环境变化及交通和经济发展的数据基础上,从对交通和经济相互影响的两个方面的分析,探讨了交通与经济的互动性。     

洋山港建设时期海域通道冲淤变化特征分析

洋山深水港区是由大、小洋山南、北两支岛链组成,形成东窄西宽面向杭州湾开口的喇叭状水域,文章结合洋山港建设以来现场实测水文、地形资料,分析了1998～2007年洋山海域通道内地形冲淤演变情况,将洋山港通道内地形变化特征概括为:随着边界的变化,地形冲淤调整迅速;南北格局呈现出"南淤北冲"的规律;长时间尺度来看,近期地形总体趋于相对平衡,略有冲刷;短时间上看,年内冲淤变化大。为洋山港港区进一步的规划方案论证提供基本依据。     

基于多属性决策的无人驾驶自主变道决策技术研究

在无人驾驶领域,随着车辆上布置的传感器不断丰富,无人驾驶系统可以从周围环境获得更多的信息,从而为车辆的自主判断行为决策带来可能。然而即使是有经验的驾驶员在进行变道动作的时候也需要格外的小心,因此无人驾驶系统的变道行为分析需要做到足够准确和谨慎,才能保证安全性,这也正是目前为止还没有非常完善的无人驾驶变道决策系统的原因。本文提出一种基于多属性决策的无人驾驶自主变道决策技术,帮助无人驾驶车辆在道路行驶中进行更有效、更安全的自主变道决策。     

华北高速公路交通事故的日迹变化与气象要素的关联分析

通过整理华北高速公路3年(2007年3月～2010年2月)逐时的交通事故资料,并与同步气象要素资料进行日迹变化分析,可以看到平均交通事故的日迹变化呈双峰型分布特征。由此,按交通事故双峰型的时间段(5:00～12:00和13:00～次日4:00),分别以年度、春季、夏季、秋季和冬季的平均交通事故与同步气象要素的日迹变化进行相关分析,其中平均气温、平均风速和平均相对湿度与交通事故的相关程度都通过了相应的统计学检验(R>Rα=0.05和F>Fα=0.05),而且在夏季5:00～12:00的交通事故高峰过程中,交通事故与风速呈指数相关的系数高达0.992 3,相当于平均风速每减小1m.s-1,交通事故的增加幅度为0.28次。为将自动气象监测的信息更好地服务于高速公路的交通安全,设计出了高速公路交通事故的气象风险等级指标。由此可见,华北高速公路交通事故的日迹变化与气象要素的分析成果,可为高速公路交通安全提供客观的科学依据。     

等容量血液稀释法治疗急性脑损伤灶周的病理学研究

采用对照试验，对实验性犬脑损伤进行等容量血液稀释（ＩＨＤ）治疗后，分析研究损伤灶周的病理学改变，以判别ＩＨＤ疗法对急性脑损伤的治疗效果。实验选用３２只犬，以钟摆式打击器制成脑挫裂伤模型，随机分４组：对照组，常规组，常规＋低右组及ＩＨＤ组。实验结束对损伤犬脑进行病理学检查并半定量计分。结果显示，ＩＨＤ组损伤灶周围脑水肿及急性损伤反应明显轻于其他组。研究表明ＩＨＤ法治疗急性脑损伤能减轻脑水肿及继发性脑损害，且不增加血管的通透性及出血倾向。     

挖方路堑坡度变更施工浅析

分析了挖方路堑施工中边坡坍塌的原因,并介绍了避免的方法及施工组织方面的技术措施。     

中国古代航运中心的变迁

中华文明虽起源于＂农耕＂,但中华民族的发展离不开航海.中国古代航海事业经历了各个朝代发展,终于在明朝郑和下西洋时达到了顶峰.由于各时期的政局各异、航海技术差别、以及国家对外贸易的策略不同,中国古代航运事业在不同时期是围绕着若干港口区域开展的.     

鸭绿江公路大桥桥区河段平面二维潮流泥沙数学模型研究

为研究在建鸭绿江公路大桥桥墩及施工栈桥等对航道条件的影响,建立了二维潮流泥沙数学模型,对桥区河段水动力条件和河床冲淤变化进行了模拟研究。研究结果表明大桥施工期桥区河段出现的剧烈变形主要由河床自然演变造成,淤积的主要原因是前期冲刷量大、河床自动恢复平衡的结果。施工栈桥和桥墩也对淤积产生一定贡献,拆除后河床会产生一定的冲刷和恢复调整。