It is necessary to examine tie down systems of wheelchair for user's safety during ride on the bus by enforcing the law for promoting easily accessible public transportation infrastructure for the aged and the disabled. We investigated the safety performance of tie down systems through the traveling test. In addition, we investigated operating time required to tie down respectively. As a result, it has been understood that the current and refined three-point tie down system and backward facing system are suitable for bus tie down system.

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In order to reduce the interior noise in high-speed trains, we have developed a prediction model of interior noise distribution based on statistical energy analysis (SEA) and boundary element analysis (BEA). Experimental results using real cars running at various velocities are used to construct Hybrid SEA model. The developed model can predict internal overall noise within 1.5 dB. A BEA model is also developed to calculate interior noise distribution, which agrees well with the measurement results. These calculation models can be used to find out optimum solutions to reduce interior noise of high-speed trains.

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The globalization and the development of IT in recent years promote the expansion of an international, interactive transportation. Therefore, the concentration of the cargo on the container terminal continues and the importance of ports in distribution increases further. On the other hand, contributing to the decrease of the environmental burden and the construction of the circulation type society is an important issue in the transportation field. In this paper the method of calculating the carbon dioxide emission in the container terminal was examined. The case study was executed for one of the major port in Japan and the amount of the carbon dioxide emission of an each transportation mode of the sea, land and the terminal was evaluated. As a result, the propriety of the proposed calculation model was confirmed.

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This paper proposes a new concept for a tail cordless elevator system. The tail cords bring a vibration and a leaning of the elevator car in skyscrapers because tail cords become long and heavy. The proposed system has rechargeable batteries on the car and electrical energy is supplied at specific floors by a contactless electrical energy transmission. This system needs a transformer which has high coupling rate. This paper shows some simulated results and experimental results of the transformer shapes for a tail cordless elevator system. The developed transformer, which has 10 mm gap, has a coupling rate of 0.88 and can supply the power at 91% efficiency.

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In the Yamanote Line, an examination of the running surface after rail grinding was performed, and the influence of the passing tonnage on some rail characteristics after grinding was investigated. Findings showed that grinding marks disappeared after about one month. Moreover, it turns out that the rail surface becomes hard immediately after grinding, and a gauge corner hardens remarkably. Lastly, it was found that a metal organization is reproduced with the increase in use of the passing tonnage after grinding.

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The terrible derailment accident happened in a Japanese metro in spring, 2000. The accident investigation committee established by the government pointed out several causes of the flange climb derailment which means that a wheel flange climbs up the gauge corner of a high rail usually at sharp curves. One of most difficult causes to understand its characteristics was the coefficient of friction. Measurements of friction coefficient of rails were carried out at 20 track sites. In this paper, the influence of operational frequency of trains, humidity and some other parameters on friction coefficient are described.

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We have developed a instrument for measuring frictional coefficient on wheels, which is called "μ-tester." The measurement procedure of the μ-tester is as follows; 1) Its roller is contacted to a measuring plane by a spring. 2) The roller is slide rotated on the measuring plane by pulling a string twisted around the boss of the roller. 3) The value of frictional coefficient is calculated from the pulling force and the normal load, which are sensed by load cells. The μ-tester can measure various surfaces such as a rail and a roller rig in addition to a wheel by exchanging a fixture. The values of frictional coefficient of a rail measured by the μ-tester were generally in agreement with that measured by a rail tribometer.

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In J-RAIL'02,an experiment was conducted with wet rail to clarify the mechanism of adhesion coefficient reduction by precipitation. During the wet rail experiment, an unexpected increase in adhesion coefficient was observed when a rail surface was cleaned during the test to eliminate the influence of rust on the rail surface. To determine the cause of adhesion coefficient reduction, a remaining section of the rail used for the experiment was put under the same experimental conditions and its cross-section was examined by electron microscope. Pores of 1 to 5μm in diameter were observed, and water getting into the pores might have lowered adhesion coefficient.

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This paper describes the experimental result of traction coefficient between two cylinders in relatively low speed drive range with the circumstances of both dry and wet to simulate rail/wheel operation. The results suggest that the characteristics of traction coefficient under wet condition differs form that under dry condition due to rust.

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The Purpose of this study is to introduce a theoretical contact-model, which can realize the creep force characteristics of Wheel / Rail interaction affected by kinds of materials, e.g. water, iron power, and especially friction modifier. In order to construct the contact model, authors have been carrying out experiments with actual bogie or two-roller-rig testing machine which can realize the contact conditions of real Wheel / Rail interaction. In this paper, authors introduce the results of investigation for the identification method of creep characteristics between Wheel and Rail.

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The concept of controlling car dynamics with the parameter of creep force by using friction modifier was proposed by the authors. The fundamental experiment of evaluating creep force characteristics with or without friction modifier by the two-roller-rig testing machine was performed. On the other, on-board spraying friction modifier system has been developed and equipped with the service car showing the effect of improved carving performance. This paper presents experimental and theoretical results of improved curving performance by the proposed method of friction modification between wheel and rail with scaled model vehicle.

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The equation ω=2V/(r_L+r_R) is commonly used in vehicle dynamics analysis to estimate angular velocity ω of a wheelset, where r_L and r_R are rolling radii of left and right wheel respectively and V is running velocity of a wheelset. However under derailment condition particularly when one side wheel doesn't contact on rail, it is uncertain that the equation is applicable to the calculation. Regarding the problem on these conditions, we introduce an angular velocity equation which is related to coefficients of normal forces acting on surface between wheel and rail. We show our equation's validity by comparing with results of experimental study, and examine its effects on creepage calculation.

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A Timoshenko beam finite element suitable for vehicle/track vibration analysis is proposed. In the present analysis the Timoshenko beam is introduced to model a rail. Since the rail is usually subjected to several moving and stationary concentrated loads, the slope deflection of the Timoshenko beam has discontinuity at the acting points of these concentrated loads. Hence, the use of the finite element (FE) incompatible with the slope discontinuity causes fictitious responses. In this paper the FE which is compatible with the deflection of Timoshenko beam subjected to concentrated loads is developed using the TIM7 element and the pyramid-shape function. Numerical results show that the proposed FE can remove the non-physical response.

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Rail dip joint has been posing a problem with deterioration of track components and track irregularity due to the decrease of flexural rigidity and joint gap, Which has so far caused considerable maintenance cost. in this study static loading tests and wheelset drop tests have been carried out to clarify the difference between fish plate joint structure and standard track structure (no joint). Also, FEM model focusing on the decrease of flexural rigidity of fish plate joint structure was studied comparing with static loading test and wheelset drop test results.

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