A high-speed internet connection system applicable to railways was developed to improve customer service and efficiency in railway operation by establishing broadband telecommunication between ground facilities and trains in operation. A mobile communication system was built for use on railways and capable of transmitting data at a transmission rate of nearly 1Gbps by applying laser beam communication technology. Field tests were performed using commercial trains, and results demonstrated a transmission rate of approximately 700Mbps on the TCP layer between the ground and a train running at a speed of approximately 130km/h.

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This paper investigates the reduction in logistics costs and carbon dioxide (CO₂) emissions which can be induced by shifting freight from road to rail, focusing on inter-regional surface freight convoys carrying manufactured goods. The article provides a summary analysis of the areas served by rail freight terminals, the relationships between, regions and a target rail corridor in the light of the rail freight sector's present situation in Japan. Using competitiveness criteria for rail freight based on expense analysis models, the distribution of shipped freight suitable for carriage by rail within the influential area of various terminals in each region is determined for the target corridor. Finally, with the help of a case study we determine the effectiveness of moving freight by rail in terms of reducing logistics costs and CO₂ emissions on the target corridor.

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Railway operators adjust timetables, and reschedule rolling stock allocation and crew duties when train operations are disrupted due to accidents. This paper discusses the problem of rescheduling locomotive assignment to freight trains after timetable adjustment has been completed. The problem is modeled as an integer programming problem with set-partitioning constraints, and is solved by column generation technique. Numerical experiments using real data have revealed that our method provides a locomotive-rescheduling plan of satisfactory quality in acceptable computing time.

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Flame resistance is an important requirement for products used in railway vehicles. Heretofore, a halogen-based fire retardant has been mainly applied; however, halogen acid is known to generate a gas which is poisonous to human beings in a combustive state. Accordingly, there is growing interest in halogen-free fire retardants. In recent years, the flame resistance of polymeric products has been increased remarkably through application of nanocomposites technology because nanocomposites, even in small quantities of additives improve their properties, of which flame resistance. For this reason studies have been carried out the application of nanocomposites to the floor sheet of railway vehicle.

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Cement-based repair materials are generally used as concrete repair patches. However, these repair materials can generate cracks and shelling, and decreasing concrete structure durability. In this study, we carried out, among others, adhesive strength and water permeability tests to improve the durability of concrete structures repaired by the aforementioned materials, to clarify the properties of the interface between the concrete and the repair materials. Results showed that water permeability played an important role in the interface between the concrete and the repair materials. This evaluation makes it possible to improve the durability of repaired concrete structures.

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Rail grinding is a traditional part of maintenance employed to mitigate rail damage such as shelling and corrugation. In order to improve the efficiency of grinding operations in the field, new grinding stones were developed and evaluated in this study. The improvement in grinding capacity of the developed grinding stone compared with the current grinding stone was confirmed, as was its improved grinding performance due to its more moderate impact on rails from a metallographic point of view despite the improved grinding performance. Based on these results, it is expected that the developed grinding stone has the potential to be introduced to field grinding operations.

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Theoretical models, such as TWINS developed in Europe, and microphone array measurements have been widely used to gain better understanding of rolling noise. However, the array measurements are often inconsistent with the TWINS predictions and give less prominence to the rail than the TWINS models. The objectives of this paper are to find out whether the microphone array measurements give a correct estimate of sound power radiated by the rail. Through the analysis of the performance of a microphone array, it has been found that a horizontal array focused normal to the rail cannot detect a large part of the noise from the rail in high frequency range where free wave propagation occurs in the rail. It is concluded that the results obtained by using microphone arrays do not reflect the radiation characteristics of the noise from a rail, and this leads to the underestimation of the contribution of the rail component of noise.

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Prediction of structure-borne noise has been a significant issue for railway viaducts, since it causes an excessive degree of noise attributable to structural member vibration. A new method of flexural vibration analysis expanded to cover whole structure for the prediction of structure-borne noise has therefore been developed. After calculation and measurement of noise in the vicinity of a floor slab of a concrete viaduct constructed on a Shinkansen line, it was revealed that the proposed method can be used as a practical means for predicting structure-borne noise.

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This paper introduces a simple prediction model for a micro-pressure wave emitted from a tunnel portal. A theoretical analysis was made of the micro-pressure wave produced when a high-speed train goes through a tunnel, considering the effects of topography around the tunnel portal. Sources of the micro-pressure wave are expressed in the terms of a monopole and a dipole. Model predictions were consistent with the model experiments where the exact Green's function was determined by the method of image.

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