This section describes differences between usual and renewed parameters for the traffic piston action, used in the decision of the necessary ventilation volume, and methods to derive such new parameters are clarified.

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This investigation targets a tunnel that has an enlarged part in the cross section in which jet fans are installed. The purpose of this investigation is to confirm a simple theoretical formula of pressure gain that we proposed for this kind of tunnel. Wall friction inside the tunnel was examined using numerical simulation, and pressure gain was re-estimated by considering the effect of this friction. As a result, the estimated pressure gain agreed with numerical simulation, so that the present formula is considered useful to estimate the pressure gain in this kind of tunnels.

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The aim of this investigation is to evaluate of transverse ventilation system for road tunnels. Developed tunnel simulator had a main duct and 390 air-nozzles for air supply and exhaust. In order to control flow rate of the main duct, the small nozzles were consisting of brass tubes and stainless steels with small orifice. The pressure distribution of the main tunnel can be evaluated by using this simulator. Measured pressure distributions of longitudinal and full transverse ventilation were good agreement with predicted value obtained from the momentum theory. However, in the case of semi-transverse ventilation, the experimental results differ from the theoretical one. In order to modify the accuracy of prediction, the current equation requires some revision by experiment data. Various transverse ventilation systems are available under the present experimental system.

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Recently, road tunnel in urban area tends to be complicated. In such a tunnel, various study for securing visibility environment for safe escape is necessary with regard to ventilation system. Therefore it is necessary to develop a ventilation control simulator and to examine control of longitudinal air velocity in the ventilation system. The simulator we have built is constructed with the solver of a set of ordinary differential equations with regard to the airflow velocities. In order to cope with the complexity of the tunnel topology, graph theory is introduced, in which the tunnel was modeled with links and nodes. We examined the air flow velocity by solving the differential equations. Simulation was carried out to clarify the behavior of longitudinal flow in fire under various ventilator operations, including imbalance operations, so that the airflow velocity can be properly manipulated for securing a safe evacuation environment. And, we report a. result applied to the Shinjuku Tunnel with the simulator we have built.

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In order to improve environment of road tunnel portals, performance of the central exhaustion system are numerically evaluated by using the sliding mesh technique. Since the moving vehicles disappeared at outer boundary, mass and energy balance is not satisfied. In order to solve this problem, averaged concentration value is calculated around the car near the outer boundary. The modified simulation can be estimated flow around continuously moving vehicles in the road tunnel. Numerical results show the central exhaustion system effectively reduced the gas emission at the tunnel portal.

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Based on the Stochastic Inclined Rods Model (SIRM) proposed by H. Matsuura and M.Nakano, we study the microscopic motion of actin myosin system including the motion of the G-actin. Our model is composed of an inclined spring (rod), a myosin head, a myosin filament and G-actins. We discuss the stochastic resonance between the myosin head and random noise. The results of calculation show that the model can convert the random motion to one directional motion, and the myosin head works as a resonator of random noise which absorbs the energy through the stochastic resonance. The intermolecular potential between the myosin head and G-actin and the inclined rod play a key role for the muscle's motion. The energy consumed by the motor is directly supplied from the surroundings (I.e., the thermal motions of water molecules). Moreover, a stripe shrinkage macro model was made, and it experimented on the experimental environment as the thermal motion of water molecules. Result of comparing these experiment and calculation was corresponding.

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We have proposed the strand-muscle actuator, which drives joints by antagonist muscles with nonlinear elastic properties like mammals. Hence the actuators realize joint angle/stiffness control easily. Having simple mechanism multiple mounting of them to make multi-D.O.F. fault-tolerant joints is also very easy, and moreover it is expected that the joints flexibly realize complex motions and adapt to environment. We have manufactured an insect-like 6-legged robot using the strand-muscle actuators for rhythmically walking. In this report the robot called SRF-3 are introduced. Their leg mechanism and walking control are described, and it is presented how the elasticity of actuators and inertia of the body or leg are efficiently utilized for walking.

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Knowledge-Array-based Reinforcement Learning (KARL) constructs a knowledge array as a knowledge database that holds optimal .motion parameters to realize requested tasks and information for seeking better learning. In this report knowledge refinement using simplex method is proposed as a method for accelerating the learning. The KARL with the knowledge refinement is applied to learn dribble and shoot behavior in hockey by a wheeled robot as a demonstrative example. The simulation result shows the behavior is successfully learned by KARL and the knowledge refinement is effective.

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The point which should be paid attention in discussing the safe driving of the vehicle is driving force between the tire and the road. Therefore, it is very profitable to know the road state as the advanced safety driving support system, and is done a variety of reports as a road state estimation method in recent years. However, the research paper which considers adaptability corresponding to the change in the road has been still little. Then, this paper proposes the system which can more quickly react to the road change than a past methodology by predicting and estimating beforehand the change in the road where a vehicle runs using the visual information from the vehicle.

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The patellofemoral joint surface of the femur of New Zealand white rabbit was drilled to create a cylindrically shaped full-thickness defect (4(φ)×7(l)). A hydroxyapatite-based scaffold for born regeneration, so-called Neobone developed by Myoui et al., was implanted into the defect with bone morphogenetic protein (BMP). Eight and thirteen months after the implantation, the cylindrically shaped cartilage/bone plug was extracted from the joint surface, and was used for static and dynamic compression tests and a friction test. Results revealed that, 13 months after the implantation, the tangent modulus of the regenerated cartilage almost recovered to control level in static compression test although the deformation rate remained much higher than control level in dynamic compression test. The friction coefficient of the regenerated cartilage recovered to control level 8 months after the implantation. These results suggest that the mechanical properties of the cartilage regenerated by Neobone with BMP for 1 year recover well except for dynamic compression property.

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Steel plates subjected to cold drawing, represented by steel plates for automobiles, are conveyed on rollers to undergo many processes, such as rolling, plating, coating and drying. In the handling system described above, occurrence of coating nonuniformity and flaws are a problem should be solved. Therefore, we fabricated equipment which enables the generation of elastic vibration via forced input of disturbance to levitation of a thin steel plate, so that the vibration isolation effect on the elastic vibration could be examined. In this study, we aim to develop a noncontact support system of the thin steel plate as high robustness using sliding mode control, which is tolerable to factors such as disturbance with .respect to variation of parameters of the system.

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The containerless processing technologies make it possible to keep the levitating material n undercooled condition and also make it possible to measure physical properties in high accuracy. However, there is a possibility that the surface deformation and internal flow of droplets can influence the undercooled condition and measurement of the physical properties. In the present study, preliminary experiments are conducted to measure the characteristic of large droplet surface deformation and the internal flow. At first, levitation experiments with a water and a melted Lauric acid droplets are conducted at normal gravity condition. Secondly, the experiments with a water droplet are conducted at microgravity condition. Thirdly, the difference of the surface behavior between a water droplet and a Lauric Acid droplet is examined with critical Weber number theory. Finally, linear perturbation theory is applied to the droplet surface deformation.

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This paper presents a dual-arm mobile manipulator in which two manipulators are mounted atop a wheeled mobile platform. Combination of the two arms' manipulation capability and mobility provided by the locomotion can extend its applicability to a broader field of applications. Here we describe the structure and control scheme of the mobile manipulator system developed. We also discuss how the two manipulators and locomotion can be coordinated in order to execute a given task in a meaningful manner.

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Homogeneous Charge Compression Ignition (HCCI) combustion has attracted considerable interest in recent years as a new combustion concept for internal combustion engine. On the other hand, two combustion concepts proposed for two-cycle SI engines are Active Thermo-Atmosphere Combustion (ATAC) and Activated Radical Combustion (ARC). The authors undertook this study to examine the similarities and differences between HCCI combustion and ATAC (ARC) combustion.

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Recently, along with high-end products, users demand high quality and high added value of steel plates manufactured by the continuous steel plate process. In the factory, the continuous thin steel plate subjected to iron and steel processes is supported on a series of rollers during processes such as rolling; the thin steel plate moves on the rollers at a speed of 10 m/s or more. In the plating process, the steel plate is conveyed 20-50 m in the vertical direction for drying, during which the steel plates are negligibly supported by rollers and other mechanisms. Therefore, plating nonuniformity due to the generation of vibration and other factors prevents the increase of productivity. To solve this problem, we have developed a new noncontact guide system for parts of the steel plate at which its traveling direction changes by applying an electromagnetic force from the direction of the edge of the thin steel plate. In this study, experimental consideration in change of bias current was carried out.

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The diamond-like carbon (DLC) films were deposited on SUS440C substrate using a plasma CVD technique. The friction and wear properties were evaluated using a pin-on-disk type reciprocating friction tester in water, changing curvature radius of counterpart. The friction coefficient did not depend on curvature radius of counterpart, and was less than 0.1. The wear of DLC films decreased with increasing the curvature radius. The wear of counterparts did not depend on curvature radius of counterpart.

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Spontaneous vapor explosion can occur when a layer of the high temperature molten material lies on the water pool or on the moisture floor. This is so-called base-triggered vapor explosion. The base-triggered vapor explosion is supposed to occur in the case of a severe accident in various facilities. It is very important to clarify the base-triggered vapor explosion from the viewpoints of the prediction and the prevention of the vapor explosion. In order to evaluate the behavior of the base-triggered vapor explosion, the experimental apparatus is designed and constructed. The experiments using U-Alloy95 as a simulating substance are conducted. Consequently, the behavior of the molten material can be observed in detail with this experimental apparatus. The digital auto-correlation method and PIV are also applied to the visual observation data obtained on the experiments in order to evaluate the velocity distribution of the molten material. Based on the velocity, the pressure at the vapor explosion is also evaluated.

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This paper investigates multiple wheeled mobile manipulators coordinating with each other under a potential collision situation. In our previous work we derived kinematic and dynamic maniuplability measures for multiple mobile manipulators transporting a common object. Main objective of this paper is to extend the previous approach to a system consisting of two mobile manipulators carrying a common object while avoiding the a collision. A newly developed simulation tool is introduced where a variety of simulation options are available. One can use such a tool for a high-level task planning as well as a low-level trajectory planning. Another objective is to verify the simulation results by conducting experiments on a real robot system. The experiment results show a good agreement with the simulation results.

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