The study has attempted to develop a method for estimating modal share of inter-city express trains focusing on mode choice behavior in inter-regional trips. Firstly, the paper indicates that most travelers are mode captive, who recognize only one transportation mode among various alternatives in their mode choice behavior. Thus, an attempt was made in this paper to develop a PLCS (Parameterized Logit Captivity and Selectivity) model to describe mode choice behavior more appropriately. This study also showed that the method developed to estimate modal share with the PLCS model was sufficiently accurate.

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This paper studies effective algorithms for designing wireless sensor networks to be used for health monitoring of railway structures. The first step reviewed optimization problems arising in railway system and highlighted the importance of maximizing the network lifetime in a poor communication environment and minimizing the total cost of the wireless sensor network in a general communication environment. Basic ideas for a life span algorithm for the network lifetime maximization problem and a Lagrangian heuristic algorithm for the total cost minimization problem are introduced in this paper. Finally these algorithms were verified with randomly generated data for the former problem and data acquired from a real WSN used for railway structural health monitoring for the latter problem.

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When train operations are disrupted due to accidents or incidents, passengers require relevant information in order to decide which train they should take. Research is being carried out on passenger decision making and their behavior when they obtain information regarding individual train situations containing prognostic, such as estimated arrival time or level of congestion on each train, in order to examine the efficacy of information provision for supporting decisions. This paper describes the results of an evaluation test aimed at grasping their train-choice behavior, in cases where train information was provided during travel delays.

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The "interim greasing" method is one of the general solutions for extending the lifespan of grease, and has been adopted for some types of induction traction motors. However, the conventional way of planning interim greasing requires leaving some empty space to refill additional grease due to the limited room. Accordingly, trouble sometimes occurs due to insufficient lubrication during the initial stages of the motor operation. To solve this problem, a new device was designed which enables grease refilling without providing an empty space by replacing the deteriorated grease with the less deteriorated one inside the grease pocket.

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Resin-impregnated bulk melt-processed high-T_c materials have already been used for several practical applications to improve the mechanical performance. A large electromagnetic force acts on the superconductors when they trap large magnetic fields, which occasionally leads to device failure. Epoxy resin can penetrate into the bulk superconductors in certain conditions. Taking advantage of the new technology, a compact, lightweight, and mobile permanent high-T_c superconducting magnet system was designed and built using melt-processed GdBa₂Cu₃O_y rings. The maximum trapped field inside the annular magnet reached 0.75 T to 2.59 T, for one to ten rings, respectively. The results clearly demonstrated that one can construct a permanent magnet system using the melt processed LREBa₂Cu₃O_y compounds. The use of simple superconducting permanent magnet for magnetizing bulk melt-processed materials can open new technological windows in various industrial areas, particular in medicine, railways, space, or naval transport systems.

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The alkali-silica-reaction (ASR) suppression effect of Li-containing zeolite prepared from metakaolin was found to be greater than that of commercial Ca-A type zeolite. Material containing more Li-ABW type zeolite suppressed ASR more effectively when used as an admixture. In contrast, material containing more Li-EDI type zeolite was more effective in suppressing ASR when employed as grout for cracks. Trial samples were made of a new crack grout with Li-EDI type zeolite, which is more effective in suppressing ASR than a commercial crack grout with Ca-A type zeolite. No problems were detected with the physical characteristics of this material when used as grout.

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Differences in flow conditions between wind tunnel tests and actual trains sometimes generate significant errors in the estimation of aerodynamic noise from devices such as pantographs and also of aerodynamic forces acting on them. In this study, turbulent flow conditions around a current collector of an actual running train were measured first. An experimental method was then developed which places obstacles upstream from the test section in a wind tunnel in order to simulate turbulent flows. Finally, the aerodynamic noise and forces acting on a pantograph model were evaluated with and without the obstacles, which confirmed that the proposed method for wind tunnel tests simulated conditions of the actual train well.

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Recently, complaints regarding railway noise have increased from residents living in high-rise buildings facing railway tracks. However, reducing noise for locations high above the tracks with conventional noise barriers is difficult, because the noise sources are directly visible from these elevated positions. This paper investigated the effect on noise of low barriers installed adjacent to rails. It was evident through acoustic tests using scale models and field tests on existing railways that this type of noise barrier is able to reduce noise even in locations high above the track. Furthermore, a prediction model of the effect of these noise barriers was proposed based on the results of the field tests.

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It is generally difficult to install extremely high soundproof walls without drastic reinforcement of the viaduct because the higher the wall, the greater the wind load and moment. A new type of soundproof system was therefore developed. The proposed system comprises a clear soundproof plate and supporting frames. The top of soundproof plate is supported by a rotary axis and all or a part of the other three sides of the plate are fixed by magnetic attractive forces and offers high soundproof performance in ordinary conditions. When the wind load exceeds the safety limit for the viaduct, the plate opens and the appropriate wind load is released. A load test and wind tunnel test were conducted and the wind load reduction mechanism of the developed system was verified.

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