Train rescheduling during disrupted service is a substantially significant task for urban railway operators. This task typically depends on the experiences and personal decisions of the professional operators. The operators use neither systematic methodologies for modifying train schedules nor quantitative criteria for measuring the quality of the rescheduled plans. Thus, operators have requested assistance in the form of a computer-aided train-rescheduling program. The authors have created a computer-aided train rescheduling system that seeks to minimize passenger inconvenience. Themethod of passenger flow for train rescheduling is discussed for realistic analysis.

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We introduce a train timetabling algorithm which determines both the number of trains and their arrival/departure times at each station. This algorithm directly takes passengers demands as an input and produces a non-cyclic timetable considering the loss of the society as a whole so that the resultant timetable is optimal both from the viewpoints of passengers and train operating company. We have conducted several experiments for actual railway lines and shown that the algorithm can produce timetables which properly fit the passengers' demands. We assume that by using this algorithm as appropriate according to the passengers demand at each occasion, meaning not to provide a fixed timetable every day, we can provide better transportation service at a more reasonable cost.

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Taking vehicle system, track system, tunnel structure and aerodynamic effort into consideration, an approach based upon the Arbitrary Lagrangian-Eulerian (ALE) scheme is presented to study the impact of aerodynamic effect on train dynamic performance in tunnels, and then analysis of lateral vibration of the train due to the loadings and irregularities is presented. The present results show that the lateral vibration of the tail car is more sensitive to aerodynamic effort than the middle car's; compared with other vibrations modes of car body, the yawing vibration of car body is more prominent. Aerodynamic effect has a greater influence on the safety performance of tail car with reference to the criteria of the derailment coefficient and reduction ratio of wheel-load.

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A static test for a CTRL-DS vehicle is described in this paper. We needed to carry out the static test according to the UK Railway Group Standard (RGS) to ensure the vehicle would operate safely before an on-track test. A new vehicle for the UK, the CTRL-DS, has been developed and we carried out a wheel-unloading and a sway test. The results from the wheel-unloading test revealed that the maximum wheel-unloading ratio was within the criteria specified in RGS. We compared the test and calculated results for the wheel-unloading and sway tests. We found that the calculated results agreed well with the test results and a calculation model could express the vehicle response for the static test. We thus concluded the CTRL-DS vehicle complied with the static test in RGS and the CTRL-DS vehicle was accepted in regard to the static test.

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A combination of increased vehicle speeds and non-improved railway tracks may have a negative impact on passenger comfort. Active technology can replace the conventional passive solution of the secondary suspension of a rail vehicle in order to maintain good passenger comfort even when vehicle speed is increased and track conditions are inferior. This paper focuses on the benefits of using a so-called Hold-Off-Device (HOD) function in the lateral secondary suspension. On-track tests have been performed with the active secondary suspension concept implemented in a two-car Regina train during the summers of 2007 and 2008. The evaluated measurement results have been very satisfactory and the device will be implemented in long-term tests in service operation. These tests will be carried out in the beginning of 2009.

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In order to verify the validity of "the Detailed Equation," we conducted a full scale experiment. The Detailed Equation is an equation of the equilibrium of the forces that act on a railway vehicle, which is similar to an equation for solving the overturning problem of a rigid body, but the external forces and the displacement of the car body are taken into account in detail. In the full scale experiment, we loaded lateral force (assumed to be crosswind) on the test vehicle, and examined the behavior of the vehicle. As a result, it has been verified that the Detailed Equation is valid for evaluating the critical wind speed of overturning or the wheel unloading ratio.

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Focusing on the larger wheel unloading and poor derailment problems in dynamic performance of the new multi-axle wagon on test lately,the paper studies extensively the multi-axle wagon dynamics of the whole vehicle system. The dynamic models of the multiple-axle wagon system are constructed. The dynamic curving negotiation of the wagon is studied through the computer simulation, and the influence of tack parameters on runing safety is analyzed. The simulation and test results show that the main reason of the resulted larger wheel unloading is due to the larger track slop of 2.86‰.

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From 2006 to 2007, 204 third generation Series 313 cars were manufactured, continuing on and enhancing the concepts of "thorough efficiency" and "improved service" of the first and second generation Series 313 (manufactured from 1998 to 2000) as well as aiming for stepped-up "passenger service" in order to bolster competitiveness vis-a-vis other competitive means of transportation. This study reports on the decrease in the level of internal vehicle noise and reduction in body ground-borne vibration, aspects which were addressed for stepped-up "passenger service."

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On JR Central's conventional lines, approximately 190km of track are replaced annually as one aspect of the company's line maintenance. The replacement work uses rails having a length of 25 meters, which are called standard-length rails, and those having a length of 200m or 150m, which are known as long welded rails. The standard-length rails are transported by rail from the Nagoya Port Materials Center and the long welded rails from the Hamamatsu Rail Center. Previously, this rail transport was carried out using three electric locomotives (EF64, EF58), one diesel locomotive (DD51), and 41 flat cars (open railroad freight cars). However, over 30 years have passed since these vehicles had been manufactured and alternatives were needed because these vehicles have become obsolete, so a railway diesel car type rail transport car was newly developed. [photograph] Standard-length rail transport car & [photograph] long welded rail transport car Figure 1: Series Kiya 97 rail transport carIn developing a rail transport car, use requirements are considerably different from those for passenger vehicles, so the design was implemented so as to take into account factors such as loading conditions, impact of rails laid across cars, and the circumstances during rail unloading. This report will focus particularly on the newly developed bogie and the parts related to the new constant low speed function.

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The problem of carbody excitation of railway vehicles due to mass imbalance of wheelsets has been discussed in this paper. Displacement-dependent rubber bush is proposed to treat this problem by introducing small gap between rubber and inner fixture. The effectiveness and validity of the rubber bush are confirmed by numerical calculation and excitation test using a full-scale test vehicle in the rolling stock testing plant.

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To develop a more suitable method of evaluating ride comfort of high speed trains, a fundamental study was conducted on sensitivity of passengers to various frequencies of vibration with respect to ride comfort. Experiments were performed on 55 subjects using an electrodynamic vibration system that can generate vibrations in the frequency range of 1 to 80 Hz in the vertical direction. Results of experiments indicated that the subjects tend to experience greater discomfort when exposed to high frequency vibrations than that presumed by the conventional Japanese ride comfort assessment method, the "Ride Comfort Level."

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We think it is difficult for an active suspension with pneumatic actuator to improve lateral riding comfort on higher speed trains because of the air consumption and the response. Then instead of pneumatic actuator we adopt an electro mechanical actuator, EMA. We evaluate the performance of EMA on our full-scale equipment modeling one car. As the result we can get the improvement of riding comfort by EMA greater than pneumatic actuator.

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We developed a model running facility to study the flow of the under floor of railway car because the flow is a main cause of ballast flying phenomena and snow accretion. The facility was set up in the test section of the Towing Wind Tunnel Facility where we can eliminate disturbances, such as natural wind by a hood. By using an automobile for the propulsion of the model train, we can make it start, run, and stop without complex, large and expensive apparatus. The model train runs smoothly on the rails because it is tracked with wire ropes.

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A coupled vehicle-track dynamic mode is put forward to investigate the effect of crosswind on high speed railway vehicle running safety. The model considers the track motion respect with to the vehicle running on it, therefore characterizes the effect of the rail support by the periodical discrete sleepers on the vehicle/track interaction. The steady aerodynamic forces caused by crosswind are modeled as the ramp shape external forces exert on the car body. The numerical analysis investigates the effects of the crosswind speed and the vehicle speed on the dynamic behavior of the vehicle/track in detail. Then, the vehicle overturning criteria and the wheel rise with respect to the rail are calculated and used to assess the railway vehicle running safety. The numerical results obtained indicate that the crosswind has a great influence on the whole vehicle running safety when the vehicle is just entering the steady crosswind scenario.

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This paper describes the analysis of the vibration characteristics of the seat with backrest in high frequency domain. In this paper, running test, impulse hammer blow test and 3D shaking table test are carried out in order to clarify the dynamic characteristics of the seat with backrest of a high speed railway vehicle, for example Shinkansen bullet train. The measurement test is done to identify the stiffness of backrest. In addition, the analysis model produces around 10 Hz translational vibration and around 30 Hz torsional of the backrest. The results from numerical analysis are compared with experimental analysis for model validation. In conclusion, the mechanism of vibration occurrence of the backrest is clarified and it gives fundamental design procedure for passenger seat.

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Aim of this paper is to explore the possible benefits brought by the use of active control of the airspring secondary suspension for high speed railway vehicles. The concept of the active suspension is developed and a prototype is tested. Then, the benefits of active suspension control are assessed by means of multi-body simulation.

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Active railway suspensions offer significant improvements in performance, but their take-up in service operation worldwide has been very small. This paper explores the possibility of mounting the actuators between vehicles rather than the conventional position across the secondary suspensions, saving weight, power and cost through a reduction in the number of actuators required. A three-vehicle train is modelled using Mathworks' MatLab software and the performance of inter-vehicle actuators is compared to conventional actuators, initially using idealised actuators for control strategy development but also using realistic actuators.

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Nowadays, extruded aluminum part is widely used for high speed train because it helps to enhance the light weight with relatively high strength. In this research, the extruded underframe part of the high speed train (Fig.1) is investigated considering the anisotropy issue with respect to its extrusion direction that is evolved during the extrusion process. In order to figure out the anisotropic characteristics, experimental approach based on the uniaxial tensile tests is proposed to evaluate the anisotropy of the extruded part, and, the directionality is analyzed by the deformation-induced anisotropy during the extrusion process considering the process characteristics. Moreover, the extruded part has the several numbers of seam line because it is produced by porthole die extrusion, so, the effect of seam line is also considered.

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