Mechanical brakes are often used by an electric train. It has a few problems like response speed, coefficient of friction, maintenance cost and so on. Therefore, methods using regenerative brakes actively are required. In this paper, the authors propose pure electric brakes which mean ordinary brakes by only the regenerative brakes without any mechanical brakes at high speed. DC-electrification system with regenerative substations can regenerate energies to commercial power system. And a train can use the full regenerative braking force. The authors furthermore evaluate the effects running time and energies with regenerative substations in proposal method.

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With respect to the reduction of the interior noise of railway vehicles, most of the countermeasures taken have been mainly passive procedures based on the mass law. As to application of the 'active noise control' to railway vehicles, only a few experiential tests have been carried out so far. This paper proposes a system to reduce the interior noise in view of the characteristics of the railway vehicles. Moreover, through evaluating in which the proposed noise reduction system as applied to a deck of the Shinkansen, the effectiveness of the system will be apparent.

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Methods for detecting any unusual conditions affecting a driver, based on driving behavior, are proposed in this paper. This study analyses driving behavior of train drivers using a train driving simulator that simulates train operation. We focus on braking behavior when approaching a station. The method of detecting unusual braking operation is examined by giving drivers mental calculation problems as a mental workload. The variance of the brake-handle operation was significantly larger when a mental workload was imposed, indicating the possibility of determining the driving characteristics of individuals. We examined the possibility of detecting unusual driving by evaluating the deceleration trajectory.

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We developed a textbook of human factors and we have been promoting safety education and training with the textbook. In this paper, we introduce the summary of this textbook and the educational program. Furthermore we show the results of questionnaire about understandability, satisfaction, difficulty and motivation of the educational program.

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To verify the accuracy of subjective risk and subjective estimation of environmental factors of possible overruns likely caused by train drivers, and to clarify the age difference that relevant to such a subjective risk, we conducted the survey on train drivers' subjective risk of overrun and environmental factors which they assumed. We compared them with the objective number of overrun and analyzed them by age-groups. The results revealed that drivers' subjective risk was a kind of accuracy, that drivers' subjective estimation of environmental factors of overrun was also accurate, and that younger underestimated the risk of overrun more than senior.

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Sensory evaluation of ride on a railway vehicle is performed based on international standards such as ISO2631. However, it is expected that this evaluation would be insufficient because of the development of technologies of a railway vehicle. The evaluation for sight and sound from the viewpoint of ergonomic and psychological perspectives might be needed as well as traditional evaluations in the future. Authors focused on the relation between sight and motion of the railway vehicle. The experiment in sensory evaluation of ride on a railway vehicle using a motion simulator was performed. In this paper, the way and results of the experiment and the environmental psychologic analysis are described.

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The adhesion level between wheel and rail has been since the beginning of railway a crucial parameter in the design and operation of rail vehicles. In the last decades, many railway organizations have suffered from low adhesion problems as consequence of the increased exploitation of the rail infrastructure. Leaves and water have been widely reported as major causes of low adhesion. Among the practical measures adopted, friction modification is one of the most popular used to enhance adhesion levels to the required minimum during traction and braking. In this paper, some results of investigations carried out with two friction modifiers are presented. Further, some of the desired properties of the friction modifiers to optimally overcome the slippery rails problem are discussed.

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This paper describes the outline of prediction method including the model for train/track/tunnel and that of wave propagation in the ground, which has been developed to predict the subway-induced vibration propagated to the ground surface in consideration of frequency characteristics. Prediction example and verification by field measurement are also carried out at a subway shield tunnel.

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The purpose of this study is to formulate the equation of dynamic interaction between heterogeneous railway track and train using two dimensional models. A new numerical method of movable load analysis for composite, long structures modeling railway tracks is suggested

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Rail grinding is a widely used rail industry technique for maintaining the quality and safety of railway track. Rail grinding can be used to restore the profile of the rails, remove surface plastic damage and remove or reduce in size very early stage surface breaking rolling contact fatigue cracks. This paper focuses on the use of rail grinding to extend the safe life of a rail that would otherwise be limited by rolling contact fatigue (RCF) defects. The optimum grinding strategy for a variety of conditions has been investigated using a model that predicts the growth of surface breaking cracks in rails loaded by rail vehicle wheel contacts, taking into account natural wear of the rail and rail grinding. It was found that a grinding strategy which removes incipient cracks in a specific period of time without being over-conservative and producing excessive material loss must take into account all traffic using the line, not just the traffic perceived to be most damaging. A mixed traffic case is modelled, revealing the potential for interaction between different vehicle types in determining maintenance requirements.

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The 3-D simulation of cyclic vertical loading tests of a full-scale railway ballasted track is attempted using the finite element method (FEM). The ballast layer is modeled as the continuum body of which the elastoplastic behavior is described by the subloading surface model with rotational hardening. The variation tendency in the relation between the vertical displacement of the bottom of the sleeper and the vertical load can be simulated using the present FE model. The simulated permanent displacement is comparable to those of test results. The large plastic strain extends from the edge of the sleeper to the bottom of the ballast layer; the frictional sliding zone can be found in the ballast layer.

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Due to higher bridge piers and massive girder loads, long span bridges over rivers tend to have a longer natural period of equivalence. Therefore, during an earthquake, train-running quality is impaired on the railway long span bridges. In this study, the authors analyzed numerically dynamic behavior of a train running on a long span bridge, and clarified the following items: Firstly, the train-running quality on the bridge becomes lower on girders in the middle of the bridge. Secondly, folding displacement at edges of the bridge did not largely affect the train-running quality. In addition, the authors studied on improvement measures by taking rigidity of piers and bearing as a parameter, and clarified that the train-running quality can be improved with provisions of a large-size caisson or a sliding bearing.

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This paper provides the influence of a pile on ground vibration induced by a moving train in underground tunnel. A coupling of the 2.5-D and the 3-D boundary element method (BEM) is used for obtaining the displacement amplitudes on the surface around the top of a pile. Numerical results show that it is possible that the presence of a pile may cause an increase of the ground vibration level around the top of a pile at low frequencies.

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Each block of continuous railway RC (reinforced concrete) rigid frame viaducts vibrates at a different natural frequency when an earthquake occurs; therefore, it is not only a vibration displacement of each block but also a angular rotation occurring at the boundaries of structures, which causes a decrease in train-running quality. In this study, a relationship between the angular rotation and train-running quality during an earthquake is formulated based on a numerical analysis.

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HSST system is a kind of urban maglev, of which maximum speed is 100km/h. We consider raising maximum speed of HSST vehicle and achieved a preliminary test run of HSST vehicle on the track of Tobu Kyuryo Line at the speed which exceeds a little more than its designed maximum speed. The result of the test has encouraged us to develop the system to a higher speed system.

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The paper describes a sensor optimisation systematic framework approach and a Fault Tolerant control scheme for sensor failures applied to an EMS maglev system. The aim is to find the minimum number of sensors that can be used in order to optimise the performance, reduce complexity and offer sensor fault tolerance. The concept is verified via simulations with the non-linear model of an EMS system.

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The study compares interdisciplinary aspects of high speed transportation systems: the respective impact on urban and regional development; demands on networkability and compatibility; the influence of current market paradigms. Societal trends and technical-ethical aspects also play a major role in the evaluation. As a conclusion, the study suggests that Maglev technology for high-speed transport should be seriously considered for new infrastructure projects in certain cases. The Maglev option should prove itself in a hard, fair qualitative competition against existing wheel/rail technology, on a project level. The results indicate that good chances can be expected for maglev, if the system comparison is fair and not biased. If maglev high-speed systems should come to be used as a new boundary-breaking transit technologies on chosen routes, this could cause significant economic and ecological changes in land usage, travel comfort and choice of type of travel.

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As a cooperative research group of 3-1 subject, which aims to improve track structures, of the Urban Maglev Program in Korea, authors are responsible for the development of rapid construction technology of maglev guideway girder for a 6.1km demonstration line. In this paper, development of maglev guideway by using precast decks, which are superior to the cast-in-place decks in quality, durability and rapidity of work in construction fields, are dealt with especially in horizontally curved routes.

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An experiment apparatus using a reduced-scale model of a Maglev vehicle was constructed, that is expected to be useful in examinations of control methods to reduce vehicle vibrations and to generate data useful in eventually improving the precision of computer simulations. This report provides an overview of the Maglev vehicle model experiment system.

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The superconducting magnets (SCM) of electromagnetic vibration apparatus for MAGLEV ground coils operate in a persistent current mode for long periods of time. In addition, almost all of the time, the current lead of the SCM acts as a route for heat leak to the inside; therefore, the authors have developed low-heat-load current lead equipment. This equipment consists of a high-temperature superconductor (HTS) lead and the low-duty metallic lead allows the SCM to magnetize and demagnetize without a gas cooling system. This realizes a simplification of work procedure and reliable operations for magnetizing and demagnetizing the SCM. This result is also valuable for further improving the SCM of the MAGLEV vehicle.

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The GFRP fastening devices are presumably effective to prevent from not only abrasion of resin but also relaxing axial tension of fastening bolts. Ground coils are applied a certain type of stress, for example electromagnetic stress, thermal stress, fastening stress, residual stress and foreign substances impact stress. We describe about the strength evaluation test results for the PLG ground coil with GFRP fastening devices on the point of the stress which caused by the electromagnetic force, thermal expansion and fastening deformation.

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Using a high-temperature superconducting wire in an on-board superconducting magnet for the maglev train has several advantages: improvement in the stability of the superconducting magnet, improvement in reliability through simplification of the magnet structure, and decrease in the mass of the superconducting magnet and the energy consumed by the on-board cryocooler. Therefore, we examined the feasibility of using 2G wires with a high critical current density in a high magnetic field. We performed numerical analysis to calculate the mass of the superconducting magnet and the energy consumption of the on-board cryocooler, taking into consideration the characteristics of 2G wires. Furthermore, we are now carrying out critical current measurements of 2G wires, while varying experimental conditions such as temperature, magnetic field, magnetic field directions and bending stress and so on.

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The RTRI conducted a study to develop a superconducting magnetic bearing applicable to the flywheel energy-storage system for railways. The study is intended for improving the driving efficiency by decrease in the frictional loss and solving the problems concerning the maintenance by applying the superconducting technology to the bearing part. In the first step of the study, the thrust rolling bearing was selected for application, and adopted liquid nitrogen cooled HTS-bulk as a rotor, and adopted superconducting coil as a stator for the superconducting magnetic bearing. Load capacity of superconducting magnetic bearing was verified up to 10 kN by static load. After that, rotation test of that approximately 5 kN thrust load added was performed with maximum rotation of 3000rpm.

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The resonance modes of the on-board superconducting magnet for the JR Maglev system actually obtained at the durability test were two in number (propulsion and levitation modes). To reduce the durability test period of the specimen by half, it was investigated in this study how those two resonance modes were simultaneously reproduced. It appears that those two resonance modes are simultaneously reproducible if the three accelerating points to reproduce its levitation mode are used, and if proper beams to shift the resonance frequencies of its propulsion and levitation modes are added.

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For the purpose of effectively compensating feeding voltage drops and reducing electricity consumption, we are developing a "Railway Static Power Conditioner for Sectioning Post (SP-RPC)". Firstly, to examine SP-RPC validity, we measured the actual train load. In addition, we simulated to compare equipment capacity. Secondly, we developed the control principle of SP-RPC. Thirdly, in order to use SP-RPC control for practical application, we developed a SP-RPC control program, manufactured the CPU boards, and conducted function confirmation tests using an actual machine panel. Finally, we carried out performance confirmation tests with a mini-model device.

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It is important to avoid the slip and to use adhesion phenomenon effectively for acceleration and deceleration in railways. A re-adhesion control system model based on a static, non-linear table is studied for investing fundamental behavior of single motored axis electric rolling stock. It is assumed that characteristic of tractive coefficient decided by microscopic relative velocity between rim of wheel and rail. The dynamic re-adhesion operation is numerically under these conditions. In addition, we make sensitivity analysis from the two parameters change of non-linear torque reductive table.

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In recent years, many different technologies that are expected to contribute to the reduction in energy consumption of DC electric railways. In this paper, the author attempts to give an overview and comparison of these technologies, and to discuss how these technologies can contribute to lower energy consumption of DC railways. The author believes the emergence and application of these technologies will eventually lead to the re-designing of the whole energy supply systems for railways.

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At DC railway substations high-voltage DC ground fault relay (hereafter referred to as a 64P relay) are currently used to detect DC ground faults within the substation. When a ground fault occurs at the substations, the 64P relay send a command immediately to open all related circuit breakers. However, some ground faults can cause damage to surrounding facilities as well as the point of the accident. At the same time, they could also possibly hamper ground fault protection due to contact faults with auxiliary energizing source. We have therefore conducted development of a ground fault relay that needs no auxiliary energizing source (DC110V) to achieve a protection system where power supply is stopped without fail in case of ground faults. We have thus-far finished production of a prototype and confirmed that the target performance has been met.

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The ability to predict the criticality of internal cracks in railway wheels requires accurate knowledge of stress intensity factors K_I, K_<II>, K_<III> under contact loads. These factors depend both on the total load acting on the wheel and on how the load is transmitted through the wheel/rail interface, that is to say, they depends on the pressure distribution between wheel and rail. However, till today the solutions commonly used consider a theoretical (Hertzian) pressure distribution, even though the real contact patch may be far different for most of the lifespan of the wheel due to wear or to the dynamic conditions. In this paper an approach is developed with the aim of solving the case of an internally cracked wheel subjected to an arbitrary contact patch and pressure distribution. In particular, attention is focused on the case of hollow wear, which makes it possible to obtain very conformal contacts. The results are discussed and compared with the analytical solutions that consider Hertzian pressure distributions with the same total load.

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The main reason for the abnormal wheel flange wear for passenger cars running on Qinghai-Tibet line is discussed. On the basis of the worn wheel profiles measured in field, the initial LM profile is suggested to be replaced by a new wheel profile called QZ, which is designed to compromise wheel flange wear for wheels running on 60kg/m rails and 50kg/m rails. In consideration of economic inspection and repair, wheel profile QZ-28 is designed with 28mm thickness wheel flange. The results show that wheel profile QZ-28 can greatly decrease the wheel flange wear than that of wheel profile QZ and LM. The results also show that to reduce the longitudinal primary stiffness of the bogies from 12.5MN/m to 10.5MN/m can greatly improve the wheel flange wear conditions, while the hunting speed and ride comfort of the passenger cars can also meet the requirement of operation.

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This paper describes methodology for assessment of minimal quality requirements for Global Navigation Satellite System (GNSS) intended for utilization in railway telematic applications. The elaborated methodology enables to provide specification of quantitative requirements for GNSS system by means of railway attributes RAMS. This process generally represents contribution for GNSS system certification, when it is necessary to demonstrate that the GNSS system meets requirements, and the system outputs are correct. In the second level, certification of the specific GNSS application must follow subsequently.

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Understanding of wheel/rail contact conditions is one of the most fundamental problems for railway vehicle dynamics. In this paper, the comparison of experiments with a full scale test track and an actual bogie, and numerical simulations which are based on the numerical procedure which the authors propose and which can be used for three-dimensional two-point contact analysis are conducted.

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Joetsu Shinkansen was the first high speed train in the world to be derailed due to an earthquake. Fortunately, the train stopped without collateral damages such as a knife-edge buckling and vehicle deviation from tracks and there were no fatalities. In this paper, some experiments on the derailment behavior using the scaled train model have been carried out in order to investigate the behaviors of the derailment of a high speed train as a trainset. Uneven distributions of the braking force caused different behaviors of a trainset.

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To prevent such dangerous situations, as the workers on the track are exposed to the risk of being hit by an oncoming train, JR West has developed and implemented a GPS-linked train approach alarm system and put it in practice. Under this system, each train lookout carries two mobile phones that automatically measure their position through the Global Positioning System (GPS). The phones trigger a train approach alarm attached to them if a train is detected on the track circuit specified in advance for each work site.

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Heavy Haul usually leads to many new problems, such as wheel wear, larger wheel/rail force and structure fatigue. Huge force caused by freight brings large elastic deformation and severe vibration of carbody. A kind of harmful high frequency vibration called chatter appears in heavy haul carbody, which is potential threat for operation safety and freight security. In order to analyze the mechanism of car body chatter, the carbody is considered as elastic body and rigid-flexible coupling system dynamics model of a certain type of gondola car which includes nonlinear friction force is established. The vibration of body in different velocity and loads case are researched and coupling parameter between freight and car is investigated.

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This paper deals with a positioning system based on the GNSS (Global Navigation Satellite System) and systems of local elements, which there is possible to be used for safety related applications in railway. In this paper namely several designs of the architecture will be described. Firstly - with three independent positioning channels - GPS/EGNOS, local pseudolites and inertial sensors system with only two independent channels - GPS/EGNOS/pseudolites together and inertial sensors and also design of the architecture with local GNSS reference station.

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This paper describes a method to predict wear rates and time until fatigue crack initiation. A computer simulation of ratcheting wear is used to model the accumulation of plastic shear deformation in the rail and predict the wear rate, based on wheel-rail contact conditions. Contact data for two types of high speed trains at two sites on the East Coast Mainline, U.K., have been obtained from multi-body simulations of train-track interaction. Together with fracture mechanics models for larger cracks, these models provide guidelines for rail grinding in order to optimize rail life and safety.

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It is known to all that derailment is the vital problem in railway transportation. As the increase of vehicle speed, the possibility of derailment due to the lateral impact between the wheel flange and the rail increases. An impact model for the impact between the wheel and rail together with an accurate kinematic analysis are presented in order to shed some light on the wheel lift derailment of high-speed vehicles.

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We have developed an on-car platform detection system using ultrasonic sensors. If a crew member tries to open the train doors when all or part of the train is not at a platform, this system could prevent passengers from falling from the train. But irregular reflection of the ultrasonic waves, due to the roughness of the slab of platform, caused unstable detection. Therefore, we have improved the system.

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Risk management is an important part of system assurance. It is widely used in safety-related system to guarantee its safety. Safety is one of important goals of railway system. The method based on risk management can find and solve the security issues of railway system more effectively. This paper introduces the basic conception of risk management, studies the whole risk management process and related tools and techniques and discusses some key points qualitatively combining with the particularity of railway system.

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This paper presents study on the detection of signs of wheel climb derailment. The sensing method and detecting algorithm were examined. A 1/10-scale model of railway vehicle including one car body and two trucks as well as a special device that can simulate various climb-up derailments only for the chosen wheel are designed and made. Based on experimental derailment tests, sensing method and algorithm for detecting signs of derailment beforehand were proposed. It was found that the peak threshold of pitch angular rate and the integral threshold of roll angular rate of truck flame can be possible to detect of signs derailment.

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The purpose of this study is to investigate the mechanism of wheel load variation of a high-speed train running on rail track with short-wavelength irregularity effecting on the running safety. In order to investigate the mechanism, the numerical simulation is conducted. The simulation model consists of the two-axle bogie and the track. The track consists of rail, rail pad, sleeper, ballast. The rail is expressed as the flexible beam described using the Absolute Nodal Coordinate Formulation in order to obtain the rail deformation more precisely. As a result of this study, we obtained further the information of the wheel load variation while two wheels passing on the rail with irregularity. That is, the wheel load variation rate of two-axle bogie model at 270km/h becomes larger in the case of the irregularity wavelength 1.1-1.2m as well as one-axle bogie model. However, the difference between the leading wheel and the trailing wheel occurs in terms of the magnitude. And the magnitude relation between the leading wheel and the trailing wheel changes according to the wavelength with the irregularity. We discuss the mechanism of these phenomenon obtained by the simulation.

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In order to design the appropriate crashworthy structure of locomotive vehicle, the two-layer thin-walled structures were taken as research objects. The efficient non-linear explicit dynamic finite element analysis software, ANSYS/LS-DYNA, was adopted to research energy absorption characteristics of the one-layer thin-walled structure and the two-layer thin-walled structure. The results have shown that the evaluation parameters (the energy-absorbing efficiency, the buffer index) of energy absorption characteristics of two-layer thin-walled structures are better than those of one-layer structures. An idea of using two-layer thin-walled structure as energy-absorbing element of crashworthy vehicle is put forward. The results of simulation on two-layer thin-walled structures with different shapes and lengths have also shown that the inner-layer length has effect on energy absorption characteristics.

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In October 2004, a Shinkansen train derailed in Japan as a result of the Niigataken Chuetsu Earthquake. This was the first Shinkansen derailment, and was caused by the earthquake during the high-speed running of the train. The East Japan Railway Company and the Railway Technical Research Institute joined forces to conduct a detailed investigation into the derailment. Following the accident, there were widespread calls for safety measures against earthquakes. It is presumed that the derailment was caused by the response motion of a viaduct resulting from the seismic motion. In this study, computer simulation was used to estimate the seismic ground motion at the site of the derailment, the response motion of railway structures and the dynamic behavior of the vehicles. The results explain the cause of the derailment in the Niigataken Chuetsu Earthquake, and indicate that the vehicles were in the motion of rocking derailment - a term meaning derailment in which the wheels jump off the rail. This paper outlines the simulation models and explains the dynamic behavior of the vehicles during the earthquake in detail.

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This paper discusses improvements to the reliability of configuration data for ensuring the safety of railway signalling systems. The authors focused on human operations in the configuration data management in order to develop an error-proof system capable of preventing inadvertent operations. The first objective of this paper will be to analyse the error-proof system by assigning hazard levels to required items, by classifying required qualities into work phases, and by mapping the error-proofing principles onto error-proofing cases. The second objective is to develop metrics from the analysis of the error-proofing cases.

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For over 40 years since commencing operation in 1964 the Tokaido Shinkansen has served as Japan's main artery of transportation. The operation of the train which was safely stabilized by ATC ( automatic train control device ) in this interval has been continued. The ground equipment of ATC met the obsolescence replacement time in 2004, and the latest technology was adopted, and in addition, new ATC system which raised reliability and efficiency was introduced, and use was begun in March, 2006. It introduces the outline of new ATC on-board equipment which operates the signal which continued in the on-board by the utilization of the position detection function of which the accuracy is high.

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More and more functional realizations rely on software in real time control systems, such as railway signalling system. In this paper, a modeling and verification methodology is presented for the object-oriented software system of railway signalling system. The methodology combines UML (Unified Modeling Language) and Petri nets to model and verify the specification requirements. The device specifications of railway interlocking system are modeled with UML, and dynamic behaviors are modeled and analyzed with Petri nets. We try to show the feasibility of improving the reliability and reducing revalidation efforts when designing and developing a decentralized railway signalling system.

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In the thesis, the scheme of the system which incorporates the transportation dispatching system with the interlocking part was designed for the industrial railway. The modeling method based on the technique of the workflow was studied to realize the automation of the working process, the general workflow net (GWFN) was defined and expanded based on the standard workflow model to model the complex system, In the expanded model GWFN, the color was used to represent the messages flowed in the workflow net, the compounded color identifier variable was used to represent the individuals. The workflow model of the dispatching and controlling system of the industrial railway was testified, and the GWFN, was proved to be a better model with the better structure, better abstracting capability.

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The system improves the safety and efficiency of railway transport, combining the advanced axle-counter with single-track semiautomatic block. Using computer, to accomplish relay-based semiautomatic block logic operation and axle-counter to check section status, it will further increase the performance of railway transport. Safety-related communication is one of the important topics in railway signal system. By referring to relevant safety-related communication standards, to research on safety-related communication of Micro-computer automatic block between Railway Stations System, the thesis introduces the basic requirements, concept model, codes, and the process, etc.

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To realize high-speed data transmission for railway signaling systems, we propose a novel modulation method combining code-division multiple access (CDMA) and quadrature amplitude modulation (QAM), called the CDMA-QAM method. We evaluated the effectiveness of the proposed method and developed a CDMA-QAM rail transmission system based on DSPs and an FPGA. In addition, we conducted a field trial using an actual rail.

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