High-Speed Rail Operations on an Existing Network: An Assessment Model for China

High-speed rail operations have the potential to reduce the long-term decline in rail passenger travel demand for the medium to long distance inter-urban markets. Such decline has been evident through most of the industrialized countries where air and road transport tend to be the dominant modes. In China, the operations of long distance high-speed rail on fully dedicated track is not very easy to implement, due to the high proportion of passengers who travel between high-speed and conventional railways. An alternative approach would be to allow for mixed operations with trains of various speeds on the same track. This article puts forward a simulation model designed to allow an evaluation of the most efficient distance for high-speed rail operations under mixed train speed scenarios. The model takes into account the main operating parameters such as passenger volumes, train speeds, capital and maintenance costs, train operating costs and energy consumption. The distance of high-speed train running on conventional rail that will yield the most economic benefit can be estimated using the model. The article includes the results of using the model for a specific example. It is concluded that large-scale high-speed trains have the potential to be successfully operated on conventional rail networks.     

Ranking of factors contributing to higher performance in the ocean transportation industry: a multi-attribute utility theory approach

The North American Free Trade Agreement (NAFTA) signed by Canada, the U.S.A. and Mexico and which came into effect on 1 January 1994, is a significant move towards further integration of the North American economies. This paper examines the likely impact of NAFTA on Canadian ports. Three channels of impact are identified. First, there are direct impacts on trade flows between Canada and its North American trading partners. In this regard we find that ports do not typically handle the types of products that are likely to be affected by NAFTA, and so the direct impacts may be minimal. Second, and more significantly, port catchment areas are likely to undergo substantial changes as they respond to a more competitive environment within the free trade area. Third, the transportation sector has itself been included in NAFTA, and Canadian ports will face increased competition from land based transportation modes. We conclude that ports in Canada must learn to work more consciously as agents of regional economic development.     

Damage detection of offshore jacket structures using frequency domain selective measurements

The development of damage detection techniques for offshore jacket structures is vital to prevent catastrophic events. This paper applies a frequency response based method for the purpose of structural health monitoring. In efforts to fulfill this task, concept of the minimum rank perturbation theory has been utilized. The present article introduces a promising methodology to select frequency points effectively. To achieve this goal, modal strain energy ratio of each member was evaluated at different natural frequencies of structure in order to identify the sensitive frequency domain for damage detection. The proposed methodology opens up the possibility of much greater detection efficiency. In addition, the performance of the proposed method was evaluated in relation to multiple damages. The aforementioned points are illustrated using the numerical study of a two dimensional jacket platform, and the results proved to be satisfactory utilizing the proposed methodology.     

An assessment of advanced transport telematics evaluation procedures

This paper reviews and critically assesses procedures which have been adopted to evaluate Advanced Transport Telematics (ATT) projects. The importance of such a review at this juncture stems from the changing position of ATT in transport planning. ATT is no longer simply a field for experimentation, where technical feasibility and user acceptance are dominant concerns. Rather it is a potential mainstream contributor to the functioning of road transport systems. For this reason, ATT project appraisal needs to be developed to the same form, level of sophistication and consistency as the appraisal of conventional transport infrastructure investment. Based on the review set out here, we argue that appropriate methods have not yet been established which, in turn, poses a number of challenging questions, since current socio‐economic evaluation procedures are not directly suited to either measuring or evaluating many of the impacts which ATT schemes are implemented to achieve.     

Simulation-based dynamic adjustments of prices and subsidies for transportation PPP projects based on stakeholders’ satisfaction

Transportation - Public–private partnership (PPP) has been well acknowledged by many as an innovative approach to the procurement of public projects. In their long-term concession periods,...     

基于手机传感器数据的交通出行调查实证评估

应用手机传感器与调查问卷, 同步采集了校园内高校学生2周的真实出行轨迹; 考虑了真实出行环境下的手机传感器数据特征, 结合高斯滤波预处理数据, 根据轨迹点的时空聚类特性, 用时空聚类算法识别了出行端点和出行时间, 结合轨迹点速度、加速度特征, 利用支持向量机识别了出行方式; 将手机传感器数据与调查问卷、查核线数据对比, 分析了手机传感器数据出行特征识别的准确程度, 验证了出行特征的提取效果。分析结果表明: 手机传感器与问卷调查识别出行链的成功匹配比例为81.66%, 说明手机传感器数据可有效记录出行轨迹; 时空聚类算法参数中核心点空间半径为26.92 m, 最小样本点为129, 时间约束为129 s时, 出行端点识别准确率为93.02%, 出行时间识别准确率为90.84%, 说明手机传感器识别出行端点和出行时间的效果较好; 当支持向量机设置类型为经典支持向量机, 核函数为径向基函数, 惩罚系数为0.797, 核参数为2.260时, 出行方式识别准确率为89.86%, 即利用手机传感器能够有效识别出行方式。可见, 手机传感器数据识别结果合理, 能为手机传感器数据应用于实际出行调查做支撑。      

Low-aspect ratio appendages for wind-assisted ships

Journal of Marine Science and Technology - Wind propulsion for commercial ships has been identified as a key component in the energy transition for the maritime industry. The sailing hybrid ship...     

A fractional perspective to the modelling of Lisbon’s public transportation network

Transportation - Urban growth originates multiscale spatial patterns, such as those of transportation networks. Here, the public transportation network (PTN) of the city of Lisbon is analysed from...