Railway systems use computers in various fields. Software development for these systems requires not only a high level of safety, but also swiftness. One method of developing software is software prototyping. Prototyping can prevent discrepancies arising in the interpretation of system specifications among stakeholders, so that users' needs are more closely reflected in the specifications. On the other hand, computer systems need software updates. While updating software, the data to be updated needs to be loaded into the computer system. To achieve this, we are developing an Online Loading System. Although prototyping is usually applied at the stage of defining requirements, in this study we applied prototyping at the stage of examining specifications by a client, and we verified the effect of the prototyping by using it in the development of the Online Loading System. The Online Loading System consists of a Loading Management Device, Device A, and Devices B with eight functions. Digital prototyping using Microsoft Excel was employed as a user interface of the Loading Management Device. Six functions were used as targets for the prototyping because these functions are implemented via operations executed on the Loading Management Device. which has a user interface for an operator. In order to verify the effect of the prototyping, we investigated the analysis results of reviewing the prototyping for all six functions. In terms of revision categories, the number of revised items with the category "addition" was the largest, accounting for 60% of the total items. The second most common revised items had the category "change", accounting for 31%. There were few items with the category "delete", accounting for only 9%. This result shows that the prototyping is particularly useful for finding omissions in the specification. We also demonstrated that most of the items revised in the prototyping were found in the initial stage of reviewing.

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In order to cope with recent changes in the environment surrounding railways and railway signalling systems as represented by Communications-Based Train Control (CBTC) systems, integrated train control systems that can evolve as customer needs change are now under development. Conventional systems have a vertical structure in which individual pieces of equipment such as Automatic Train Control (ATC) equipment, electronic interlocking equipment and facility monitoring equipment operate independently. However, this vertical structure has raised some problems due to the structural complexity, functional overlaps and different principles between different pieces of equipment. In contrast, integrated train control systems are horizontally and hierarchically structured, consisting of a "function layer", a "network layer and a "terminal layer. This horizontal hierarchical structure is intended to make the systems lean, simple and evolvable according to customer needs.

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We introduce a case study of IT security analysis for the wireless transmission system of JRTC-W, a communication based train control system. We used the "attack tree" method together with an IT security risk evaluation procedure of IEC15408 (CC) to assess potential threats to the wireless transmission system of JRTC-W in conformity with the lifecycle safety management process of IEC62278 (RAMS). Attack Tree is an FTA-like purpose-oriented tree-form analysis method of hierarchical decomposition of complex attack scenarios into simple and non-divisible (assets). We identified 43 attack methods for individual wireless communication (from Zone controller to On-board controller) for instance, and classified 10 different kinds of assets. We report how the analysis has been done.

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In Japan long waiting times at level crossings is a social issue. To solve this problem effectively we have developed a microelectronic level crossing controller with built-in constant warning time control logic. Conventional logic would require extensive design and construction as well as testing would as logic is different at each crossing. We succeeded constructing logic without track circuit information and standardizing logic by implementing two train counting logics. Next we carried out indoor tests. For this test, a number of test patterns based on the experience and knowledge of developers were systematically examined and implemented. In this test we have systematically examined many test patterns which were restricted within human experience and knowledge conventionally. Specifically, possible events are listed at each stage of the life cycle of RAMS (IEC62278), and test items are described with both top-down FTA (Fault Tree Analysis) approach and bottom-up FMEA (Failure Mode and Effect Analysis) approach. Moreover we narrowed down the test patterns by focusing on both number of items and number of procedures to carry out in a limited period of time. Finally we carried out a field test to evaluate functions and environmental resistance during long-time operation in the field environment at Hikawa crossing between Omiya and Toro on the Tohoku line over 8 months. As the result of the indoor test and field test were successful, we are planning to commercialize our level crossing controller in fiscal 2015. By using our development, we expect to reduce time for design, construction and testing. Furthermore, we also expect to reduce the number of relays and lead to reductions in cost. By the above-mentioned effect, our development leads to promote introduction of constant warning time control for level crossing and contribute to society.

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In Japan, automatic train control (ATC) systems, one type of railway signaling system, transmit train control information by using analog signals based on amplitude modulation (AM) in the audio frequency band. To realize highly functional train control by increasing the data transmission speed, there have been many studies on digital ATC that transmits train control information by using digital signals based on phase shift keying (PSK), and these systems are employed in some railway lines. In practice, however, it is difficult to install digital ATC because it is impossible to ensure another transmission band for digital ATC signals due to the existing track circuit configuration and interoperability conditions, and there are many railway lines in which analog ATC is still employed. To overcome this restriction, we proposed a novel railway signaling system using mixed digital and analog signals. We employed quadrature PSK (QPSK) for digital signals and developed a transmission device using digital signal processors. We evaluated the transmission characteristics by conducting a basic experiment. In addition, it is important to improve the performance of digital ATC systems after they were completely shifted by using mixed digital and analog signals. Therefore, we also studied a performance improvement method by applying quadrature amplitude modulation (QAM) and code division multiple access (CDMA) in which the increase of data transmission speed is realized.

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To meet the growing demands of further broadband communications even in the railway scenarios, millimeter (mm)-wave radio communication is a promising solution. In order to establish its system we have to consider some fundamental issues: mm-wave radio propagational properties, handovers across cells especially for high-speed railways, and spectral efficiency. We here propose a novel mm-wave train radio communication system based on our linear cell concept. To simultaneously satisfy both two different aspects "bandwidth-guaranteed" and "broadband" as a train radio system, i.e. both the passenger use and operational use, we raise five key enablers for realization of our concept. Through the discussion in this paper, we reveal the benefit and significance of the focused key enablers comprising our mm-wave linear cell concept.

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The southern part between Shin-Aomori Station (at the north end of Main Island) and Shin-Hakodatehokuto Station (at the south end of Hokkaido Island) of a new high-speed train line called Hokkaido Shinkansen was nearly completed by the end of 2014 and will be opened in 2016. In a range of 37.3 km at the south end of Hokkaido Island, a number of various types of geosynthetic-reinforced soil (GRS) structure were constructed: i.e., 1) GRS retaining walls (RWs) having full-height rigid facing for a length of about 3.5 km, having fully replaced the conventional type RWs; 2) in total 29 GRS bridge abutments, having fully replaced the conventional type bridge abutments; 3) a GRS integral bridge, the world-first one at Kikonai; 4) three GRS box culvert structures integrated to adjacent GRS RWs; and 5) nine GRS protection structures at the tunnel entrance. These GRS structures have been constructed most densely ever for railways, which is definitely so for high speed trains. This paper describes the design and construction of these GRS structures with several lessons learned from this project are summarized.

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A concept for a novel track switch arrangement has been developed at Loughborough University, which, through a novel locking arrangement, allows parallel, multi-channel actuation and locking functions for the first time. This switch has been developed as part of the REPOINT project, and is referred to as the REPOINT switch. Existing track switches generally use a single-channel actuator and lock, and undergo an intensive maintenance and inspection regime to ensure an acceptable level of reliability/availability. This paper demonstrates, through mathematical modelling with very conservative assumptions, that an increase in switch availability is possible alongside a corresponding decrease in ongoing maintenance intensity using the REPOINT multi-channel approach. The paper firstly introduces the theory behind the design of the REPOINT switch, using a switch with 2-out-of-3 redundant actuation and sensing channels as an example. An existing switch is analysed using real-world data as a benchmark. Availability is determined by the target time in which Maintenance Teams must have replaced any failed components, expressed herein as τ. Availability measures are obtained as functions of τ which show the range of possible switch availability against maintenance response times, for the given set of assumptions. The results show that for a REPOINT installation, gains in system availability are possible even when response times are set many times longer than current standards, indicating a significant reduction in ongoing maintenance cost.

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The maglev train is the strongest candidate for the next-generation railroad system. Among the advantages, lesser vibration and noise due to the non-contact mechanism and the eliminated possibility of derailment are noticeable merits for a high-speed train. It should be noted that the air gap is affected by dynamic behaviors of the maglev train and guideway. Their behaviors also influence to the air gap. Therefore, accurate and precise physical model for the maglev train-guideway interaction system including a control algorithm of the air gap is indispensable for the reliable air-gap control and maglev-train operation, especially for the safe and reliable operation of a maglev train. In the present study, dynamic responses of an urban maglev train-guideway interaction system including a control algorithm are rigorously investigated. The train is represented by a mass-damper-spring system which is levitated electro-magnetically. The guideway is modeled by a three-dimensional frame structure. The electromagnetic forces between the train and guideway are assumed to have small fluctuations from their static values and linearized with respect to the values. In order to control air gaps for levitation, the active control algorithm which was used for the urban transit maglev system in Korea is employed. Dynamic governing equations for the maglev train-guideway interaction system including the control algorithm are derived. Dynamic responses of the system are examined using the governing equations. These analytical results are also verified with the comparison of field measurement tests at Incheon Airport Maglev Railway.

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The conventional seismic standard specifies that the seismic inertia force acting on a train is modeled as a uniformly-distributed load which has the upper limit force of 30% of railway vehicle weight assuming that railway vehicles produce damping effects or do not always oscillate in the same phase as structures. However, the damping effect has not been specifically identified and the upper limit is unreliable, because actual railway vehicles and structures provide the complicated vibration system. The object of this paper is to evaluate dynamic effects of railway vehicle and concentrated load effects of the moving train on the maximum displacement response of structure during earthquakes, and to develop a reasonable modeling method of running railway vehicle in seismic design. As the result of numerical simulations, it was found out that the dynamic effect of vehicles affects the structure response during earthquakes, and the effect depends on the characteristics of the earthquake, the degree of the plastic behavior of the structure and the yield frequency. The structure response varies in the range of from -50 to 20% due to the dynamic effect of railway vehicles when the weight ratio of the structure to the vehicle is 1. In addition, the concentrated load effect of the moving train significantly increases the structure response in the case where the four wheelsets sandwiching the coupler are placed on the structure at the time of the maximum acceleration of earthquakes as compared to the case assuming train weight to the distributed load, although it is a rare case, and the displacement response varies in a range between -70 and + 100% approximately when the weight ratio of the structure to the vehicle is 1. Finally, an equivalent weight method that can evaluate the dynamic effect of the railway vehicle using the equivalent weight ratio β_<eq> was proposed for enabling a simple and reasonable modeling in practical seismic designs.

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Friction Management has become an integral part in daily operations of many railways. Friction Management includes the combined application of a gauge face lubricant and a top-of-rail (TOR) friction modifier. This paper will deal with the friction modifier aspect of friction management. The general concept of a friction modifier for TOR application will be highlighted and explained. The key properties of a friction modifier include optimized friction conditions between wheel and rail and positive friction/traction characteristics over a wide creepage range and different application rates. Furthermore, the effects of a friction modifier are discussed in this paper by referring to extensive laboratory and track testing. The reduction of lateral forces will reduce wear and damage of track components, namely the rail and wheel. The positive friction characteristics will impact squeal noise appearance, vibration emissions and corrugation development. The optimized friction conditions will mitigate derailment potential, improve ride quality and will allow for reductions in energy and fuel consumption. This differentiates a friction modifier from a gauge face lubricant that simply aims at reducing the coefficient of friction to a minimum value. Finally this paper will highlight the importance of considering friction management as a part of the railway system and not as a stand-alone solution in order to achieve the maximum system benefit.

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In this study, in order to clarify characteristics of dynamic wheel load on open steel girder bridge, a numerical simulation of the dynamic interaction between vehicle and bridge has been carried out focusing on open steel girder bridges. Consequently, it has been clarified that the correlation between the curvature of the track irregularity and the maximum wheel load is not a simple proportional relationship by influence of beam deflection on steel girder bridges.

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The FE-based coupling method with ballast settlement elastoplastic analysis and track vibration analysis considering unsupported sleepers is developed to accurately evaluate the sleeper-ballast interaction force in deteriorated track. The present method is used to investigate the evolution of the ballast settlement around a junction of concrete slab and ballast layer. In the analysis considering unsupported sleepers, the maximum of the sleeper-ballast interaction force at the sleeper away from the junction increases in progression of the number of loading cycles at higher rate than that without loose sleepers. A larger maximum force causes a larger permanent deformation of ballast layer. This is because the progression of ballast settlement leads to an increase in the number of unsupported sleepers in neighborhood of a supported sleeper.

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For expansion of adaptable sections of continuous welded rails, we should confirm the limit value of the gap of a rail breakage. The limit value of the rail gap was set at 70mm based on the running tests on a straight track and a fundamental study about condition of wheel/rail contact on straight tracks. On the other hand, examinations to justify this limit value on a high speed track or a curved track have not been implemented. The purpose of this study is development of a numerical dynamic simulation model that is capable of simulating the behavior of a vehicle at the time of its passing a rail gap. This study is concerned with a rail gap on a curved track in high speed railway. In order to construct the model, it is necessary to calculate the contact force between wheels and rails with high accuracy. For its purpose, this study uses a contact model using the finite element method to evaluate the wheel/rail contact force. The creep force necessary for verification of the simulation model was calculated using the analysis model to simulate the creep force characteristics test with use of full-scale wheelset, which incorporates the proposed wheel/rail contact model. Also running tests on rail gaps were carried out, to confirm the accuracy of the simulation model. The analyzed wheel load and lateral force and the result of these tests were in good agreement with each other. According to the results of verifications, the proposed simulation method is capable of simulating behavior of a vehicle at the time of its passing a rail gap with high accuracy. In conclusion, it is possible to clarify the relationship between rail gaps and rail contact forces with the newly developed method. In the future, we are planning to establish the limit values of the rail gaps with more improved accuracy of the simulation.

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The purpose of this study is to improve a sharp curving performance through the use of the torsion equalizer mechanism. When cars pass through a curved section with a small cant transition ratio on a sharp curve, the change of wheel load distribution would be caused due to carbody torsion. Particularly, the outer wheel load on a leading axle would be decreased at an exit of transition curve. The torsion equalizer mechanism is configured by two mechanical links or two containment fluid circuits which join between front and rear bogie bolsters in lateral directions of the front and rear bolsters. When one wheel unloading is caused in a transition curve, the mechanical link or hydraulic circuit would work between front and rear bogies. In case that the wheel load on a leading axle is decreased, the link or cylinder would be extended and generate downward reaction force to the bogie frame. Consequently the wheel load on a leading axle would be recovered. The effect of this mechanism could be confirmed that the wheel load distributions on sharp transition curves of a car equipped with the torsion equalizer mechanism are improved by the stationary test of an actual scale vehicle. Also confirmation of the robustness of the torsion equalizer mechanism (such a car weight including passengers, air springs deflated / inflated, and change of primary suspension characteristic due to aging) was obtained through the use of multi-body dynamics simulation to support an effect of the torsion equalizer mechanism.

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Improving running safety in sharp curves, especially in transition curve, reducing lateral force and wheel load variation are very important. In this paper, the newly developed system "a Torsion Equalizer mechanism (T.E.)" for reduction of wheel load variation and the results of on-track tests to evaluate the effect of this system are introduced. It is common that the wheel unloading phenomena are caused by rail twist due to reduction of superelevation in transition section of sharp curves. Because of the reduction of superelevation at a transition curve, rail twist occurs between each position of the front and rear bogies on a car. Because the carbody cannot be transformed to follow a rail twist, large wheel unloading is occurred at outside wheel of leading wheelset in a car. In order to improve the curving performance, the authors installed T.E. that reduces wheel unloading caused by the rail twist due to the reduction of superelevation. The side bearers of bogie bolster on the same lateral sides are joined by the containment hydraulic circuit so as to be coupled. At the exit of a transition curve, the side bearer in the rear bogie on high rail side is forced up. Then the upward force generated in the rear bogie is transferred to the side bearer in the front bogie through the containment hydraulic circuit. Finally the side bearer in the front bogie on high rail side is pushed down and the wheel load in the front bogie on the high rail side is recovered. T.E. was equipped on Tokyo-metro Chiyoda line train, series 16000, and performed on-track tests to investigate the effect of this system. The wheel unloading in transition curves were improved at most 16pt in the tests.

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Shinkansen has been one of the world's safest and most reliable means of transportation. Its high reliability is based on high technology and experience developed over the past years. We have conducted a research on the brake system to improve braking performance by the optimization of the braking system. When we optimized the brake system, we should consider both of the hardware and the software side technology. The former is like the structure and materials of brake disc and pad, and the latter is like the skid controller and the shearing rate of brake force. When an earthquake occurs, mechanical brake is the only brake system available for Shinkansen since regenerative brake system cannot be used due to power cut.The heat load to the brake disc and the brake pad increases drastically when mechanical brake is applied. Therefore, brake discs and brake pads are required to have sufficient durability against the damage which accumulates in them during deceleration from the maximum velocity to the complete stop. In other words, they are required to have high wear resistance, high heat resistance, high strength, and high toughness, while providing stable braking force.This study is aimed at improving braking performance by developing a new brake disc and brake pad with new structures and aterials.In this paper, we report the development of the brake disc and pad which showed higher braking performance and reduced temperature rise in laboratory and commercial-line testing.

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Rolling stock manufacturer increasingly seek to sell their products outside Japan. And one target market with a high potential for railways components, systems or even complete new vehicles is the European market. However, a particular challenge for European market entry is the complex approach and the homologation process. The harmonization of European railways, started during the early 90's, created its solid foundation based on European directives, regulations as well as on national rules and laws in every member state. The paper shows the challenges during the commissioning of rolling stock based on European and national regulations using Fire Safety as an example. As Fire safety is one of the main research fields in railway transport systems and due to a high number of passengers by unit area and delayed evacuation conditions, ambitious requirements on material characteristics, vehicle design and safety systems are laid down in standards, such as series EN 45545 as well as the requirements of "Technical Specifications for Interoperability" (TSIs). The requirements are based on a holistic approach with particular emphasis on personal safety (i.e. passenger and staff on board). Additional requirements can also arise from a fire risk analysis needed, for e.g. running capability performance of the respective train. To ensure a correct verification process as well as adequate and coherent product design documentation, independent inspection bodies must be involved in the initial project phase. These "third parties" support the manufacturer during the entire design and approval process and finally confirm the product's compliance to applicable standards as required by the respective authority.

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When railway vehicles run at exit transition curve, track twist produce wheel load variation. Especially if vehicle has air suspension, behavior of leveling valve increases diagonal differential pressure (Twist component of unbalance of air suspension pressure). Increase of wheel load variation makes margin of tight curve passing safety small. In order to improve running safety, reducing wheel load variation is very important. In this paper, authors have developed newly secondary suspension "connecting of front and rear air springs" for reducing wheel load variation in transition curve. This valve system can flow small amount of air at low differential pressure and flow large amount of air at high differential pressure. The developed air suspension system has evaluated with trial running in the test line. The test data show diagonal differential pressure is improved proximately 40%.

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Improving running safety in sharp curves, especially in transition curve, reducing wheel load variation is very important. When railway vehicle runs in transition curve section, superelevation gradually reduces continuously and the plane consisted of right and left rail is twisted. This track twist produce diagonal differential pressures of secondary suspensions in the car which makes unbalance of wheel load in the car. So we developed newly system "connecting front and rear air springs" to reduce wheel load variation. Connecting front and rear air springs has an effect of cancellation of diagonal differential pressures, which can be realized by additional air pipings and differential pressure valves. We installed this system in Tokyo Metro Chiyoda line train, and carried out test run to evaluate the effect of this system. The test data show wheel load variation rate of proposed system was improved compared to conventional system. And the diagonal differential pressure (equal to car body twist) was significantly improved with this system.The test results show that wheel load variation rate is improved approximately from 20% to 30%, as a result, derailment coefficient data was improved approximately from 15% to 25% for each curves in the test.

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Flange climb derailment is considered to be profoundly influenced by friction coefficient between wheel flange and rail. However, the coefficient varies greatly according to the surface condition of a wheel and rail, atmospheric conditions, and the frequency that a wheel passes over the rail. And it is also deemed to be hard to directly measure the coefficient as the process of derailment has not been made clear yet. Flange climb derailments were achieved by the authors using EMUs in practical use equipped with newly turned wheels. To find the cause of the derailments in the experiments, the EMUs were repeatedly operated on a sharp curve track and such values as the derailment coefficient, the attack angle of the wheel to the rail and the wheel lift-up value from the rail were continuously measured under the critical wheel-climb conditions. The results of the experiments are reported in this paper.

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Railway is an important transportation in the world and its safety is highly valued. The wheels and axles are key components on locomotives and rolling stocks in China railway, so the failure of the wheel or axle may lead to severe accident, especially in high speed or heavy haul application. To avoid train accident, daily check and regular inspection are necessary. The surface condition of wheel and axle, parameter of wheel such as diameter and wheel profile can be checked by train operator using eye or instrument. Magnetic particle testing is used regularly to find the surface defect generated during wheel and axle application. For detecting inner defects of wheel and axle, such as material defects or cracks, ultrasonic inspection is applied usually on production line during manufacturing, and different ultrasonic inspection methods and equipment are also applied regularly to find the defects in different checking maintenance levels to ensure the safety of train operation. Now, the condition of all the CRH wheel and axle is under monitor and control. The similar wheel and axle safety guarantee system is under construction for Chinese heavy haul locomotives.

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Railway safety is of vital importance, researchers strive to improve the safety of railway vehicles using various approaches. This paper concerns the development of a sign detection system that detects abnormal conditions leading to the flange-climb derailment of a railway vehicle negotiating a sharp curve at a low speed. This research is the continuation of previous research completed at the University of Tokyo. In previous research, a basic detection algorithm was developed using 1/10-scale vehicle experiments. Following the development of a sign detection algorithm from the scaled model, verification of the sign detection algorithm was then completed using real-scale bogie experiments and Multi-body dynamics simulation. This paper focuses on additional improvements completed on the detection algorithm to shorten the detection time. The improved algorithm was verified by using past situational and experimental data published by Japan Transport Safety Board. Verification of the improved algorithm though conducting experiments using a real-scale bogie is also discussed in this paper.

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The friction heat generated by twenty thousand tons freight trains during emergency braking process or long ramps velocity modulation braking process affects brake shoe was researched by ANSYS and scanning electron microscopy. Also, the limit amount of wear about shoe was calculated theoretically. The temperature and stress fields of shoe was simulated by ANSYS, friction and wear state of shoe's friction surface was watched with scanning electron microscopy. The results show that the highest temperature of non-wear shoe is 206.2℃ in the 28^<st> second of the whole emergency braking process, the maximum stress is 15.4Mpa in the 32^<st> second. Yet, the highest temperature and maximum stress appears at the end of the long ramps velocity modulation braking process, which is 651.1℃ and 62.4Mpa separately. When the wear reaches certain extent, the highest temperature of shoe is more than 900℃. During the braking process due to fiber breakages and the base material drops caused by fiber fracture, the friction surface of shoe forms defects and tiny hot cracks. Under the condition of the gradient is -12‰ and the limit speed is 80km/h the amount of wear on the brake shoe reaches 20.96mm per ten thousand kilometers. Reducing compression modulus and increasing the thermal conductivity of the brake shoe moderately both reduce the heat storage for brake shoe. Also, improving the adhesive strength between reinforced fibers and the substrate can avoid emerging the defects and cracks on the friction surface premature.

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In this study, we have constructed a detailed contact model between a wheel and track structure to express the post-derailment railway vehicle behavior more accurately, and then we have incorporated the model into the numerical program DIASTARS III which is able to analyze dynamic interaction between the vehicles and structures, and post-derailment railway vehicle behavior. Firstly, we have proposed a method by which the running track is divided into several strips along the rail direction, and the geometric track irregularity and the contact spring between the wheel and the track structure for the each track strip are discretely defined as a function of the position in the rail direction. Secondly, we have proposed a method which can express the phenomenon that the derailed wheel collides with or jumps over the rail. Finally, to verify the proposed methods, we have carried out derailment analyses by using DIASTARS III. We have confirmed the post-derailment vehicle behavior responding to the variation of the geometric irregularities of the running track and the contact springs between the wheel and the track structure. In addition, we have confirmed that the proposed methods can express the phenomenon that the derailed wheel collides with or jumps over the rail.

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West Japan Railway Company continuously conducts research and development for further safety of the car from various aspects and has developed the passengers' fall from platform prevention equipment at the coupling section between head cars as one of the valuable result. Already the anti-falling safety barriers at the coupling section of intermediate cars had been equipped, but there was no such measure between head cars coupling section. Just simply attached side cover in front of the head car may prevent driver's visibility and capture strong wind influence that will cause the head car specific technical problems. But there was the passenger falling down accident between head cars coupling section. It strongly promoted the development of countermeasure preventing such accident for further safety improvement. At the developing stage, we analyzed the passengers falling process from the platform as in three phases which are "precaution against falling", "prevention against falling" and "countermeasure at falling" As the result, we decided to introduce on the service cars by developing the "falling prevent sound alarm system" as the precaution meaning and the "falling accident prevention equipment" as the falling prevention measure. This paper will introduce the developing process of the passengers falling down preventing measures at the between head cars coupling section.

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SPARCS (Simple-structure and high-Performance ATC by Radio Communication System) is a train control system based on radio technology independently developed by Nippon Signal Co., Ltd. The system allows movement blocking operation and single line bidirectional operation suitable for high density carrier transportation which is required in urban traffic lines. SPARCS provides the core ATP (Automatic Train Protection) functions of CBTC (Communication Based Train Control) systems and ground-train bidirectional data communication control functions. The stability of the wireless communication function is the most important to operate CBTC system stably. SPARCS possesses some characteristics necessary for radio communication of the train control system. They are the stability, robustness and the secrecy. SPARCS was installed in Beijing subway line No.15 and the signal system is operating for stability since December, 2011. This paper describes the technical features of the SPARCS radio communication network. Also it shows an overview of the signaling system of the Beijing subway line No.15.

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In order to guarantee the safety and efficiency of the train, a dynamic time warping (DTW) algorithm was introduced to train axle temperature monitoring in this paper with respect to abnormal data of the train axle temperature. After the corresponding data's preprocessing, different axle temperature sequences were recorded into pattern bases as reference sample in the training phase. In the process of recognition, we compared the similarity of real-time train axle temperature and reference sample in the pattern bases. And dynamic time warping distance according to the ideology of dynamic programming is calculated, then we can get two quantitative index of sequences similarity, so as to obtain the condition monitoring results. The simulation results show that the response time is less than 0.4 second and the false alarm rate is less than 3%., meanwhile, it also eliminates the influence of noise and jump.

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Objective safety assessments by ISA (Independent Safety Assessor) in agreement with international standards including concepts of SIL, RAMS, etc., are required for guided transportation systems (e.g., railways) intended for overseas expansion from Japan. In this paper, a study on standard safety assessment methods which are internationally acceptable is reported. IEC 62425 (Safety Case) and IEC 62278 (RAMS) were selected as preferred international standards with which the standard assessment methods of this study were required to be in conformity. As an ISA, NTSEL has been carrying out many safety assessments and confirming that the probability of seriously dangerous events is sufficiently low. The assessment criteria used to be the equivalent of the excellent safety achievements of Japanese railways or higher, but recently, numerical criteria, such as SIL4, are employed. Application of FMEA and FTA is recommended by IEC 62425, and procedures of FMEA and FTA are described in IEC 60812 and IEC 61025 respectively. Such descriptions about FMEA and FTA in these international standards match with NTSEL's traditional safety assessment methods, and, therefore, these NTSEL's methods will continue to be adopted. As stated above, a basic structure of standard ISA's safety assessment reports has been presented.

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Japanese railway had an extremely successful safety record in comparison with that of other countries. However, this excellence in safety is not necessarily favorable for railway export. Under the condition that conformity to several international standards, RAMS standard (IEC 62278) in particular, is required for development of railway export, design balance is important between safety and reliability. This paper describes the consideration of design balance between safety and reliability for future Japanese railway.

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In recent years, the rapid development of Chinese rail transit has gathered profuse scanty practical experience. At the same time, it also has encountered a series of problems during the rapid development, especially major issues such as the safety of rail transit. To conduct in-depth research on the major issues in a timely way is of great significance to the perfect construction and healthy development of operations of Chinese rail transit in such a critical period of development.This subject take the research and breakthroughs in rail transit safety guarantee system as a starting point, focusing on major issues related to the development of the national rail industry. On the basis of a detailed analysis of the present situation of rail transport, carry out research, and formed a number of specific recommendations. The Recommendations are: redesigning and improving rail transportation safety guarantee system from the system level, focusing on the whole life cycle of rail transit safety control, but not rigidly adhere to the local, individual parts, which is in order to establish the basic framework and basic requirements of the whole rail transit safety system. Developing different rail transit safety system, different safety standards and different security technologies according to different train types and different speed grades conditions. Specific comments are as follows:(1)perfect China's rail transit safety guarantee system, achieve security control of the whole life cycle;(2)improve the level of railway transit safety technology, establish scientific safety technical standards;(3)develop rail transit RAMS evaluation technology, build RAMS control system of the whole life cycle.

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In recent years, heavy rainfall in Japan has been increasing due to global warming although it originally has high precipitation. Over the past years, some underground stations were inundated due to heavy rainfall. Moreover, there is a possibility that more underground stations would be inundated in the future. Therefore, it is important to consider appropriate measures against inundation because flood in underground stations would cause serious damages which endanger the safety of passengers. In this research, we developed the prototype of system to evaluate measures against inundation at underground stations in case of flood damages with the simulation technique. We carried out case studies to verify the effects of some prevention against inundation by this prototype-system. As a result, by the prototype of system, we can calculate the time required for evacuation, the number of passengers who walk through inundated spots and, finally evaluate the effects of measures against inundation. Also, by case study with the developed system in a virtual station, we confirmed that it is possible to verify the effects of combinations with each countermeasure against inundation. In conclusion, we could achieve some positive results in the development of this system. However, our system is not enough practical to be utilized at this stage. At this stage, we are considering to improve flood damage model in order to be system based on the actual phenomenon than the present. Finally, we would like to develop this system continuously to be utilized practically in order to contribute to promote countermeasures against inundation in existing stations.

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This paper introduces the new methods for train operation control in strong winds at East Japan Railway Company (JR East) based on previous papers. In order to secure running safety of trains in strong winds, JR East implements operation control such as speed control and operation suspension at prescribed wind speeds. In the new method of wind observation, the spatial average of instantaneous wind speeds observed at the same time by three anemometers is applied. Furthermore, the 3-second time average wind speed by an anemometer has almost equal performance to the spatial average wind speed observed by three anemometers. In the new method of calculation of critical wind speed of overturning, the Railway Technology Research Institute (RTRI) Detailed Equation is employed. The methods have already been introduced on some sections on the advance of other lines.

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In order to assess a railway safety technology, it is required to examine, among other criteria, the efficiency of the technology. Therefore, it is necessary to analyze causes of rail accidents to quantify the risks and furthermore, to reduce them if is possible. Because of this topicality, an important component of risk evaluation is the economic allocation of train accident damage costs. In other words these allocations enable to calculate the value of preventing a casualty (VPC) or to justify safety technology investments. One objective of the article is to present a method for analyzing past accidents, their causes and to allocate them to the corresponding accident category. This method should help to justify investments in the safety infrastructure. The accident reports of the National Investigation Bodies (NIB) and the information of databases like the European Railway Agency Database of Interoperability and Safety (ERADIS) or the National Transportation Safety Board (NTSB)-Database of the United States, which are partially based on these reports, were used for the examination of the relevant accidents. In addition to the common known UIC categorization of accident causes, a third level of accident causes were added to evaluate the accidents accurately enough. So accident causes can be allocated to the equivalent safety technology. This method of allocation is described in the paper. For testing the hypothesis, that a allocation of accident causes and safety technology is possible with this method, the method was used as example for the analyzes of the hot box detection technology. The results of the evaluation support the assumption. It is possible, based on the analyzed accident information, to find out and to examine the relevant accidents causes for the related safety technology and to calculate the costs of these specific accidents.

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This paper provides the statistical analysis results of ropeway accidents in Japan in the past ten years from 1999 to 2008. Statistical analysis includes (1) analysis of conditions in which ropeway accidents occurred, (2) cause analysis of the accidents and (3) analysis of conditions in which similar accidents occurred. Conventional analysis of ropeway accidents in Japan was mainly focused on the case analysis of each ropeway accident. Aim of this paper is to prevent the recurrence of ropeway accidents based on the above statistical analysis results. The result shows that occurrence of similar ropeway accidents is remarkable and accounts for about 94% of the overall ropeway accidents. Authors find reduction of ropeway accidents requires reduction of similar ropeway accidents.

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Parametric instability of a wheel moving at a constant speed on a railway track is discussed. For this purpose, this paper presents an analytical formulation in which the damping is considered in rail supports. Since the dynamic behavior of a railway track depends on the rail axial load arising from the temperature change, this effect is also taken into account in the present mathematical model. Through numerical analyses, it is found that the eigenvalue which characterizes the quasi-steady-state dynamic reaction of the moving wheel and track is translated toward the positive imaginary number under the existence of damping. The range of unstable velocity is then narrowed by the introduction of dissipation into the track structure. Moreover, the critical damping at which the instability zone vanishes is obtained. Although the compressional rail stress reduces the instability speed, its contribution to the critical damping is insignificant.

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A restraint on the wear of train wheels and rails of a railway is required to improve running safety and reduce maintenance cost. Wear is one of the problems that need to be settled in managing railway property. In order to deal with this problem, it is fundamental that we understand the mechanism of wear between rail and wheel. For this purpose, in this study an experimental approach to wear development using test stand that has controlled environment with respect to contact parameters and factors influential in causing wear is taken. In the experiments conducted, a 1/5 scaled rolling stock test stand consisting of a wheel set and two rail rollers is used. A comparison was made of the worn wheel surfaces and the creep force under various contact interface conditions such as coefficient of friction and radius of curvature. The contact interface conditions included a dry surface condition and a friction modifier-applied condition, in which low coefficient friction and high positive friction were used as friction modifiers. By studying photographs of worn wheel surfaces and the creep forces under various conditions, the mechanism of wear development at the rail/wheel contact point is examined. In particular, we clarify the influence of the creep force on the wear coefficient and the status of the worn wheel surfaces.

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Each of four wheel in one bogie has a different wheel/rail contact point because of understeering in a sharp curve negotiation. In general, the gauge corner of outside rails and the top of inside rail are lubricated in a shape curve. Each of wheel/rail contact points makes different friction coefficients. Therefore, a bogie has several curving performances according to the each of wheels friction conditions. In this study, an ideal condition in a sharp curve negotiation is proposed by selecting a lubrication combination for each of wheel/rail contact points. The result of stand tests about the influence on curving performance of conditions of wheels lubrication and the evaluation of wheel/rail contact force above are also reported.

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A series of experiments on the traction between wheel and rail were carried out for the purpose of obtaining the fundamental knowledge of how to prevent the occurrence of wheel slips in driving and wheel slides in braking. A twin disc rolling contact machine was used for the experiments by varying the surface roughness and the temperatures of wheel and rail discs, as well as the sprayed water. Adhesion coefficient acquired from the relationship between slip parameters and traction coefficients which can be obtained by experiments and film parameter which is the minimum EHL film thickness with smooth contact surfaces divided by the combined roughness were estimated. Relationship between the adhesion coefficients and combined roughness shows that the adhesion coefficients have a local maximum or almost constant values at 1〜3μm combined roughness and become large with an increase of the temperature of the wheel disc in the range where adhesion coefficients have a local maximum or almost constant values, however, the influence of temperature becomes smaller with the decrease of the combined roughness in the region of less than 1μm. Re-adhesion which is a phenomenon characterized by the dramatic increase of the traction coefficient occurs in some experimented conditions.

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Induced airflow from passing trains will generate the adverse impact to the environment or people near the train. Especially the aerodynamic forces on the human body generated by the high-speed train wind would endanger the safety of pedestrians or roadside workers. In addition to the scene that the train runs in the open air, the scene that the train passes by the tunnel or trains pass by each other in the tunnel also can generate strong train wind, which is also named as piston-wind. The train wind could deteriorate rapidly for the train passing the tunnel and trains passing by each other in the tunnel, compared to that generated by the train running in the open air. Consequently, the train wind could be an important issue for the running safety of the train in these scenes, and could also be a threat to the workers in the tunnel. In the present paper, the characteristics of train wind for the train passing by the tunnel and passing by each other in the tunnel is studied. Three-dimensional numerical simulation is performed, and the dynamic mesh technique is also utilized to simulate the passing process. Several speeds are investigated, which includes the speed of 160 km/h, 200 km/h, 250 km/h, 300 km/h and 350 km/h. Numerical results reveal that a linear relationship exists between the running speed of the train and the speed of the train wind for both scenes. For the train passing the tunnel, the maximum speed exists at the entrance of the tunnel, while the train wind in the middle of the tunnel keeps relatively constant. The speed of the train wind increases with the speed of the train with the slope of 0.097. For trains passing by each other in the tunnel, maximum speed exists both at the entrance and exit of the tunnel, while a relatively low speed for the train wind could be observed in the middle of the tunnel. The speed of the train wind increases with the speed of the train with the slope of 0.073.

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A large moving model rig was constructed in Institute of Mechanics, Chinese Academy of Sciences in 2014 which possesses the functions such as a bidirectional operation of 1:8 scaled of three-car train model, the maximum experimental speed of 500km/h. It uses the compressed air and the eddy-current magnetic braking technique to accelerate and decelerate the train model, respectively. The rig can use for the train aerodynamic investigations of different scenes such as single-train or two trains passing by each other with Mach number similarity in open air and in tunnel et al. At present, the measurement system of tunnel pressure waves has also been established. The principle of moving model rig realization and the relative experimental results of tunnel pressure wave measurement are introduced in the paper.

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Independently rotating wheels are usually used in LRVs so that passengers can get on and off it easily. LRVs have high risk of derailment on tight curve sections existing in LRT because independently rotating wheels give few self-steering ability to LRVs. In order to smoothly negotiate tight curve sections, LRVs need high self-steering ability. In addition, they also need high running stability for its operation around urban area. Independently rotating wheels with negative tread conicity (negative tread IRW) are proposed as wheel design to get high self-steering ability. It has wheels with negative tread gradient and gives high self-steering ability to LRV by using outwardly gravitational restoring forces. In previous research, it is confirmed experimentally that a LRV with negative tread IRW can run on tight curve section smoothly. On the other hand, in another previous research, it is confirmed that a LRV with negative tread IRW causes unstable oscillation in high speed running. In this research, independently rotating wheels with oblique axle (oblique axle IRW) is proposed to improve running stability of negative tread IRW. Oblique axle IRW can get outwardly gravitational restoring forces with camber angle of wheels. In addition, it has few tread gradients. This paper clarifies that improvement effect of running stability on LRV by use of oblique axle IRW with numerical analysis.

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Since the Law for Promoting Easily Accessible Public Transportation Infrastructure for the Aged and the Disabled was enacted to ensure the convenience and safety of elderly and handicapped people travelling with the use of public transportation, a short time ago, Partial-Height Platform Screen Doors designed to ensure the safety of passengers has drawn attention. As Partial-Height Platform Screen Doors become widely used, safety is required to be ensured under different installation conditions. Among them, ensuring the safety at curving points on the platform is one of the major challenges. Gap filler is used for ensuring the safety of passengers at those points by filling the gap between trains and the edge of the platform. Before the development of this equipment, equipment was operated manually by station staff. Thanks to the development of this equipment, automatic control operation without operation by station staff has become available. As Gap Filler is installed within the structure gauge, the development includes not only safe motion of the equipment but also enhancement of the reliability of the system. This paper provides an outline of Gap Filler, required specifications and its reliability and safety. This paper also introduces the system used in conjunction with Partial-Height Platform Screen Door and refers to the latest trend.

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Wireless charging technology for heavy-duty vehicles, such as electric buses, has been actively investigated with a view to accelerating deployment of an important form of eco-friendly transportation. Major standardization bodies recently chose the 85 kHz band as a global common frequency band for light-duty PHEV/EV, based on extensive studies on co-existence with other radio systems. The usage of the common 85 kHz band for a wireless charging system for heavy-duty vehicles would lead to rapid introduction of the wireless charging system while avoiding potential interference with other radio systems. We developed and evaluated a prototype wireless power transfer system for rapid charging of electric buses using the 85 kHz band. The rapid wireless charging system is composed of four components: a power transmission circuit generating 85 kHz band high-power signal from a commercial power source, two sets of transmit and receive charging pads that resonate in the 85 kHz band, a receive circuit that transfers 85 kHz band high-power signal to DC and charges the battery, and a control circuit that uses 2.4 GHz wireless LAN for communication. Achievement of the target by prototyping and evaluating this wireless charging system was confirmed: the maximum electric power received was 30 kW or more, the maximum misalignment tolerance of the transmit and the receive charging pads was +/-10 cm or more, and the longest transmission distance between the transmit and the receive charging pads was 12 cm or more.

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Most passengers take fixed routes commuting to a place of work or to school every day. In Japan, nevertheless, they are often confused when train operations are disrupted due to some accidents, even with these daily itineraries. Because in urban areas there are a large variety of different types of trains such as local, rapid, express, etc. which are operated on a certain single line and stop different stations, the arrival sequence of these trains can become disrupted even with a small delay. For this reason, passengers have to gather relevant information in order to decide which train they should to get on. Today, however, the railway operators provide limited information regarding operation conditions of each train. In this paper, therefore, the questionnaire survey carried out targeted daily commuters in urban areas, for whom train operations were most likely to be disrupted and for whom the need for more information at such times is the greatest, in order to seek an appropriate method of providing information that is desirable for both operators and passengers. The survey was conducted assuming that the schedule disruptions were slight enough to not need traffic operation rescheduling on a virtual rail route. The respondents answered about their own decision making for train choice and their reasons for choosing them when they obtain the detailed information about the situations of individual trains. It shows that passengers' decision make and behavior for train choice deeply depends on a combination of the items of provided information, which can suggests that how railway companies provide information to passengers for appropriate train choice.

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Urban railway lines, upon which large conurbations crucially depend, suffer from chronic congestion and prolonged travel times during peak hours, and improvement of capacity and reduction in travel times are desperately needed. Also, competition with other modes of transport is ever intensifying. These necessitate the realization of a very high performance railway, called in this paper as "ultra-convenient rail transport" (UCRT), which can provide services that much better fit individual passengers' needs. Because needs of the passengers are very diverse, so should the services provided by UCRT. This naturally leads to the conclusion that ultra-high frequency operation is essential for UCRT. In this paper, the authors present the discussions on possible new technologies that can be used to realize UCRT, and the impact they may have on the attractiveness of the services provided by the new railway system. The techniques upon which the authors would discuss in this paper are: (1) moving block signalling systems, (2) on-board turnouts and (3) soft coupling. In the discussion, the pure moving block system (PMB) which stands inside the so-called 'brick wall' assumption and the relative moving block system (RMB) that breaks the 'brick wall' assumption are compared, and significant improvements in performance may be achieved when RMB is combined with on-board turnouts. These techniques contribute to further reduction of headways between trains, and thus contribute to the realization of UCRT.

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The authors propose the development of "Ultra-Convenient Rail Transport (UCRT)" to make a drastic improvement of passengers' convenience (or reduce their inconvenience) on rail transport and thus strengthen its competitiveness over other modes of transport, especially road transport with the expected emergence of autonomous (driverless) cars into the market in the near future. UCRT is expected to have the capability to better meet individual needs of the rail passengers; in order to do that, drastic increase in train frequency to the level high enough to be called "ultra-high frequency" would be essential. In this paper, the discussions are made as to how this drastic frequency improvement can be made possible, especially by means of the introduction of new scheduling techniques. Realizing ultra-high frequency train operation would require some breakthroughs, such as synchronization control of trains under the moving block signalling system, together with the introduction of the concepts of scheduling schemes designed for higher frequency operations, such as the "zonal separation" schemes for radial commuting railways or "skip-stop" schemes for more general cases. In this paper, the adoption of the synchronization control to replace a single long train in a railway schedule under conventional scheduling scheme with a group of shorter trains under the synchronization control, and demonstrated that the passenger inconvenience can be reduced by the introduction of this new scheme. Other discussions, including the resilience of the high frequency train operations, are also made in this paper.

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In this paper, a model of the mixed heterogeneous traffic is used for the determination of the optimal freight train inserting. The optimization problem is based on maximum energy effectiveness of the accelerate run of some the forcibly delayed passenger services. This adjustment is suitable to fast recovery the punctuality of the passenger trains. A heuristic algorithm for selecting the optimal time-slot for the freight train assumes to multiple shifts the line its travel from the no penalty position. We examine the case of using the proposed methodology to determine the insertion point for the freight train travel in real operating situation. The analysis shows that the insertion of the freight train into the middle part of the light trains' packet is the most effective solution on the energy criterion.

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In large urban areas, such as Tokyo metropolitan area, multiple railways compete with each other in a densely developed railway network. Given the proximity among lines and stations, catchment area of stations can easily be overlapped. This means that it is difficult to identify station catchment areas quantitatively which usually play an important role in developing station-based passenger demand forecasting models with adequate accuracy. In order to overcome the abovementioned issue, the SCAD model to specify quantitatively station catchment areas has been developed. The station demand forecasting model with SCAD model can predict the future volume of station users changing in accordance with the progress of urban renovation projects within the target station's catchment area in a relatively short term. The method was then applied to several stations in the central district of an urban area in Japan to demonstrate prediction of station uses volumes. Combination of the developed model, passenger flow survey data and passenger flow simulation system can be applied for considering which kind of countermeasures is appropriate, when these should be implemented. Additionally, this paper also discusses the direction of improving SCAD model in a near future.

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How has the frequency distribution of domestic leisure travel changed in the past few decades? Where has change occurred? What effects has the new HSR (High Speed Railway) service had on of travel generation patterns? In order to answer these questions, we analyzed temporal changes in the travel frequency distribution of overnight and one-day leisure travel by the Japanese from 1991 until 2011. The results of the temporal analyses indicated that the average frequency of overnight travel decreased over 20 years, the zero frequency ratio increased, and the inequality of travel frequency among individuals also expanded. Moreover, the authors propose a travel frequency model and explain spatiotemporal change in terms of three effects (age, birth cohort, and period in each prefecture). The analyses using the model indicated that the travel frequency distribution was very different among prefectures. We then compared the spatiotemporal change of the frequency distribution with HSR construction. As a result, we did not observe any positive effects of the new HSR services on travel frequency. This indicates that HSR service may affect only destination choice or mode choice, not on travel generation patterns of leisure travel.

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