钢轨闪光焊接亮灰斑的成因及消除

钢轨闪光焊接产生亮灰斑,特别是灰斑露头和灰斑超标,对焊头质量产生极大危害,是导致焊头断裂的主要因素之一。通过探讨灰斑物质来源,明确闪光焊接过程中灰斑的形成过程,采取措施有效解决实际生产中的灰斑问题,总结归纳有效消除亮灰斑的思路和方法。     

轨道式水泥混凝土摊铺机的使用

通过对轨道式水泥混凝土摊铺机的使用,找到了一些正确的使用方法,给出了影响平整度的因素及注意的问题,以及水泥混凝土本身对摊铺质量的影响,同时给出了提高摊铺质量的方法.     

Modeling a rail transit alignment considering different objectives

An optimization model for station locations for an on-ground rail transit line is developed using different objective functions of demand and cost as both influence the planning of a rail transit alignment. A microscopic analysis is performed to develop a rail transit alignment in a given corridor considering a many-to-one travel demand pattern. A variable demand case is considered as it replicates a realistic scenario for planning a rail transit line. A Genetic Algorithm (GA) based on a Geographical Information System (GIS) database is developed to optimize the station locations for a rail transit alignment. The first objective is to minimize the total system cost per person, which is a function of user cost, operator cost, and location cost. The second objective is to maximize the ridership or the service coverage of the rail transit alignment. The user cost per person is minimized separately as the third objective because the user cost is one of the most important decision-making factors for planning a transit system from the users’ perspective. A transit planner can make an informed decision between various alternatives based on the results obtained using different objective functions. The model is applied in a case study in the Washington, DC area. The optimal locations and sequence of stations obtained using the three objective functions are presented and a comparative study between the results obtained is shown in the paper. In future works we will develop a combinatorial optimization problem using the aforementioned objectives for the rail transit alignment planning and design problem.     

Evaluating web site service quality in public transport: Evidence from Taiwan High Speed Rail

More and more public transport system passengers plan their trips by using website services. The passengers’ perceived service quality of a website plays a crucial role in recognizing the satisfaction of a transportation service chain. This study aims to investigate the passengers’ perception of electronic service quality (e-SQ) delivery through the Taiwan High Speed Rail’s (THSR) website, by adopting the Rasch measurement model to measure a subjective latent construct: perceived e-SQ. The Rasch model can compare person parameters with item parameters, which are then subjected to a logarithmic transformation along a logit scale to clearly identify which e-SQ measurement items are appreciated by certain passengers. Analytical results show substantial differences between the perceived e-SQ of various personal characteristics such as age, income, and trip types. Empirical results also demonstrate that passengers are most satisfied with the website’s accuracy of information and introduction to the THSR stations’ surrounding area, but are not satisfied with instructions when a transaction fails as well as the carriage layout of the THSR. Our analytical results also identify which service items lead to the perceived e-SQ difference between business trip and leisure trip passengers. The relationship between the two main attribute dimensions – quality of transportation information provided and quality of website services – are also further examined. The empirical results can help a transportation system service operator to better understand how passengers perceive e-SQ and to suggest what should be improved.     

引导新城发展的轨道交通分层分级策略研究

新城建设是目前许多大城市缓解城市问题的主要手段之一,轨道交通在引导新城发展中发挥了重要作用.本文通过对轨道交通"点"、"线"、"面"三层的等级结构进行分析,着重分析了轨道交通点层枢纽、线层走廊对新城的引导策略,指出轨道交通在引导新城点层开发、轴向扩展方面的重要作用.     

深圳市轨道交通二期线网票价研究

为制定深圳市轨道交通线网票价方案,首先分析了现行票价所存在的问题。通过分析轨道交通票价制定的相关影响因素,提出了深圳市轨道交通票价制定原则。同时,借鉴国内外典型城市轨道交通票制票价经验,结合深圳市轨道交通发展现状,提出了轨道交通票制宜采用里程分段计价,确定了合理的票价方案。最后,对深圳市轨道交通线网票价提出了几点建议。     

灰色GM(0,N)法在轨道交通噪声预测中的应用

以实测样本数据为基础,根据灰色系统理论对列车车速、距轨道中心的距离两个因素进行灰色关联度分析,发现前者对线路侧方噪声级的影响要强于后者;分别建立线性回归模型和GM(0,N)模型,将预测值和实测值进行比较,发现灰色GM(0,N)模型的预测方法性能良好,是一种优秀的噪声预测方法.研究成果对轨道交通噪声影响因素的主次识别、降...     

大件货物海上运输的惯性力研究

绑扎是保证重大件货物海上运输安全的必要手段之一,而计算货物运动惯性力是绑扎设计的前提.通过介绍基于船级社协会统计数学模型得出的经验公式和基于船舶谐摇运动方程的理论公式两种海上货物运动惯性力计算方法,简要分析了其不同的思路和特点,指出现行的国际海事组织<货物积载与系固安全实用规则(CSS规则)>是经验公式中货物重心距船舶水线-2.4～11.5 m范围内的惯性力计算规范.并通过三个不同的典型大件货物运输实例,指出经验方法在理论公式中所对应的最大横摇角和最大纵摇角范围分别为15.～25.和5.～7.5°,结论可用于指导重大货物海上运输的系固绑扎设计,并为运输重大件货物的风险控制提供参考.     

抗浮锚杆在U型槽中的应用

宁远道口下穿立交设计中,地下水位高,道路U型槽设计中,岩层较浅的条件下,利用抗浮锚杆起到抵抗地下水浮力的作用,通过理论计算和现场试验来确定锚杆的入岩深度,已达到经济、便捷、安全的效果。     

关于城市轨道交通运营维修施工计划管理模式研究

城市轨道交通运营维修施工是一项非常重要的运营生产组织活动,一个合理、科学的运营维修施工计划管理模式既可以确保维修施工安全、提高维修施工作业效率,又可以减少对正常运营的影响程度和范围。本文通过对国内已开通轨道交通城市运营维修施工计划管理模式的分析、探讨,研究厦门轨道交通运营维修施工计划管理模式。