A container terminal consists of many agents. They include gantry cranes, transfer cranes (TCs), internal trucks, and external trucks. Many containers are moved from the coastal terminals of Japan to inland sites and vice versa. The workload distribution among storage blocks (container stacking areas) changes over time in a container terminal. Therefore, TCs, which are mobile cranes for container handling in storage blocks, have to move appropriately among blocks according to the distribution, and the efficiency of yard operations depends heavily on the productivity of TCs. In the proposed method, we use a look-ahead methodology to determine the dynamic deployment of TCs, in which the workload distribution is estimated with simulated operations of TCs and adequate movement of TCs is obtained with searching methodology in real time. The simulation results from 10 hours of operation with 600 containers show that the proposed method can improve the efficiency of yard operations (average waiting time of trucks) by 65% in comparison to cases without movement of TCs and by 42% in comparison to the simple rule-based method. These results demonstrate the effectiveness of the proposed method.

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Pressure fluctuations on the sides of narrow (1067 mm) gauge trains running in tunnels are measured for the first time to investigate the aerodynamic force acting on the trains. The present measurements are compared with earlier measurements obtained with the Shinkansen trains. The results are as follows: (1) The aerodynamic force, which stems from pressure fluctuations on the sides of cars, puts the energy into the vibration of the car body running through a tunnel. (2) While the pressure fluctuations appear only on one of the two sides of the trains running in double-track tunnels, the fluctuations in opposite phase on both sides in single-track tunnels. (3) The on-track test data of the narrow gauge trains show the same tendency as those of the Shinkansen trains, although it is suggested that the pressure fluctuations develop faster along the narrow gauge trains than the Shinkansen trains.

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Continuous unloaders play an important role in handling bulk materials at ports and so should be fitted with antiseismic devices to protect them in case of emergency by severe earthquakes. Continuous unloaders usually have a hinged-leg type structure and their posture changes over a wide range during operations. For the seismic design of continuous unloaders and to optimize antiseismic devices for them, these features must be taken into consideration and the dynamic behavior of unloaders under representative earthquakes must be clarified. This paper proposes an antiseismic device using linear ball bearing and laminated rubber bearings installed between the traveling gears and the fixed legs on the land side. To clarify the dynamic behavior of a continuous unloader in hinged-leg structure under representative earthquake excitations, experiments using a 1/15-scale model of an actual unloader, modal analysis and time history response analysis using the finite element method were conducted, and the performance of the proposed antiseismic device was investigated. The validity of the finite element analysis was evaluated by experiments using the 1/15-scale model, and the effects of posture on dynamic behavior were also studied in the analysis. The time history of the response acceleration, displacement and the response reaction force at leg points as well as the natural frequencies and modes were calculated and discussed.

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In this paper, we report the development of an adaptive torque distribution control system for a light duty truck with a parallel hybrid system powered by a diesel engine and an electric motor. This control system analyzes the current driving conditions in real time on an on-board electric control unit and calculates the optimal torque distribution for fuel efficiency accordingly. We verify the effects of adaptive torque distribution control through simulation and experiment, and show that in a variety of usage environments, fuel efficiency is improved in comparison with a conventional control system.

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In this paper, we developed a lateral dynamic model of an unmanned vehicle by using a system identification method and designed a lateral controller. The system input is the steering wheel angle of the vehicle with constant longitudinal speed and the output is the yaw of the vehicle. With the system identification method using subspace method, to achieve a control objective, we designed a robust lateral controller using the model equation. We, also compared the robust control performance designed by using the system identification method with that of the physically modeled system.

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The drive force of engine cooling fan increases in the proportion of engine size and operation velocity. It's one of the reasons of engine power consumption and is the main source of engine noise and vibration. Generally, insufficient fan revolution results in overheating and poor cooling operation. In case of engine overcooling the driving horse power decreases and results in engine noise. If a fan is kept in operation continuously, poor fuel economy, unwanted noise and battery dead will be caused. In case of cooling fan by thermostatic coil spring, even the advantages of viscous cooling fan clutch, it's impossible to control precise engine temperature and fan revolution velocity because of its only On/Off function for valve lever by bimetallic spring with two different thermal coefficients. Hence, it's imperative to apply high edge electronic systems to solve strict technology issues and it's essential to apply electronic sensor and actuator for vehicles which requires high environmental protection and reliability in harsh service areas. In this paper, the optimization of engine management system (EMS) controlled viscous cooling fan was investigated to control cooling fan drive and its velocity by direct engine temperature and engine management system according to PWM signals.

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In this paper a brief review on the observability and estimability analysis of GPS/INS is presented. There have been various analysis results on the observability of INS errors. However different INS error dynamics models and reference frames of INS mechanization have been used in the observability analysis. Moreover, the analysis framework was not unique. In this paper, known observability analysis results are summarized first. Then relatively general analysis tools to handle system model perturbation on the observability and estimability is given.

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In recent years, high speed railway vehicle technologies have been studied and investigated in order to develop their performances with the objectives of improving riding comfort, noise reduction and high efficiency from environmental perspective. One of the essential performances is current collection stability. Operating at high speed conditions, the current collection system which consists of contact wire and pantograph suffers from contact force variation. In order to reduce such variation, pantograph design should be comprised by active control thus realizing stability. Numerical analysis can be applied to model the current collection and in particular simulate the contact force variation itself. In this study, Finite Element Method and Absolute Nodal Coordinate Formulation are used to model the wire. A free vibration experiment that focuses on the tension of wire is performed to validate the numerical models. The validated result from the experiment demonstrates the accuracy of the numerical analysis in modeling the wire. The techniques are then applied to model the contact wire for the contact force investigation. The result indicated the availability of pantograph design via simulation to achieve steady contact force.

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