Surface design is important when designing micro/nano-scale devices as their function and performance are largely determined by the surface properties of adhesion, friction, wear, and wettability, etc. For the purpose of surface design, we have developed a method to pattern molecularly thin liquid lubricant films coated on solid surfaces with ultraviolet irradiation through a photomask. To investigate the effect of patterning on depletion and replenishment properties of lubricant films, we performed pin-on-disk type wear tests for patterned 2.0-nm-thick perfluoropolyether Zdo14000 films coated on magnetic disk surfaces. The pattern shape included radial, circumferential, and dotted ones, and the pattern linewidth included 0.5, 5, and 10μm. We found that the depletion and replenishment properties were mainly affected by pattern linewidth and pattern shape, respectively. The 0.5-μm patterned films showed lower depletion than the 5 and 10-μm patterned films, and the radial-patterned films showed faster replenishment than the circumferential-patterned films.

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This study aims to clarify the cause of the friction when the ball array slides on a plane including its directionality. A physical model was constructed to explain the friction based on ratchet theory. To verify the anisotropy, the sample was a line-and-space structure, of which length was 40 mm and spacing between arrays was 20 mm. Also, in the way of that curvature radius of microspheres was 0.3-10 mm and load was 1-10 N, it compared the experimental values and simulation that the impact curvature radius and load on friction coefficient. It was found that the experimental results are well correlated with simulation except extremely lower contact pressure.

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We examined the friction properties of the nanostripe structures under dry conditions. The nanostripe structure had multilayer film consisting of soft metal (Ag) and hard metal (Cr) that was deposited on a micron scale slope array on a Si substrate. The thickness of each film was ranged from approximately 20 nm to 180 nm. We measured the friction force on the nanostripe structures by rubbing with six kinds of slider (Mo/Ni/Ti pin, SUJ2/Al_2O_3/Si_3N_4 ball) using a reciprocating friction tester. The specific wear rate was examined from the depth of wear track on the nanostripe structure that was measured by laser microscope. The nanostripe structures showed stable friction coefficients of about between 0.2 and 0.3 in a vacuum (2×10^<-4>Pa). When increasing the thickness ratio of Cr, the friction coefficient became more stable and the wear rate decreased.

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Fluororesin exhibits low friction by making a transfer film, which leads to sliding of the same kind between fluororesins, on the counterpart surface. In this study, in order to improve in both fluororesin transfer ability and retention ability, periodic structures with submicron scale periodical pitch and groove depth were formed on the counterpart surface. The effects of the periodic structures on transfer of fluororesin and friction coefficient were verified. As a result, it was confirmed that the periodic structures oriented along the sliding direction are effective in reducing friction, wear and adhesion because of firm fluororesin transfer film formed on the periodic structures.

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CO(carbon onion particles) are spherical carbon nanoparticles that have a mechanical strength and a reducing effect of friction. By these properties, CO are expected as a new lubricant materials to lead frictional parts to a high function and a lifelong duration. But the problem is shown that CO on sliding surfaces are come off just after sliding. To solve this, these were carried out so far that surface modification of OC and addition of nanometer structure onto sliding surface. These studies have problems that are degeneration of friction property of OC and high fabrication cost. Thus, this paper focuses on fine grooves which can trap lubricant on sliding surfaces with easy techniques. And when I identify surface roughness as fine grooves, the ball-on-disk tribology test to sliding surfaces that CO dispersed was carried out due to investigating effects of additive amount of CO and surface roughness of a substrate on its tribological performance. As results, small roughness of sliding surface was better in terms of minimum friction coefficient, and large one was in terms of stability of friction coefficient. Wear track observation after the friction tests revealed that OC were confirmed along grooves on the surface having large roughness but few CO confirmed on small roughness. Therefore, this revealed that tribological performance of CO maybe affected by interrelationship of additive amount of CO and the depth of fine grooves.

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Effects of cutting tool surface textures with short pulse laser on friction between a tool rake face and chip are investigated. One is a sub-micron size texture which is well-known as LIPSS(Laser Induced Periodic Surface Structure) fabricated with femtosecond laser. Another is 10 micron sized ordered structure with large depth. Some Experimental results indicated that former developed hydrodynamic effect adjacent to cutting point if lubricant is supplied and a groove direction of LIPSS is inclined against cutting edge. Moreover, latter indicated significant reduction in cutting forces even in dry cutting condtion if the texture is positioned about twice the uncut chip from the cutting edge.

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In our study, we challenged to apply the established techniques to fabricate nano-composite materials using C_<60> to TiAlN, which is harder than TiN. Development of the synthesis method of C_<60>/TiAlN nano-composite must give effective industrial contributions. C_<60>/TiAlN nano-composite thin films with constant thickness 200 nm were deposited on Si(100) water-cooled substrates using by the same method with both Ti and Al sputtering targets for 30 minutes. The concentration of C_<60> molecule powder were changed in the range from 0.5 to 40 wt.%, and the evaporation temperature was controlled in the range of 523-723 K. The structure analyses of all nano-composite thin films showed that XRD patterns indicated only TiAlN crystalline structure, and FT-IR analyses clarified kept of C_<60> molecule structure at all concentration . From these results, the microstructures of C_<60>/TiAlN nano-composite thin films were confirmed to consist of both C_<60> molecule and TiAlN crystalline metallic compoumd. Nano-indentation hardness made clear that the value of the composite films of 2.0 wt.%C_<60>/TiAlN showed the maximum hardness of 20 GPa and this value was increased up to 20 % larger than that of TiAlN thin film. Furthermore, the wear resistance of this composite thin film showed improvement of 4.5 times

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Functional group on silica surface is controlled for modification of wettability. Silica substrate is firstly terminated with trifluoromethyl group (-CF_3) by silane coupling treatment, which exhibits high hydrophobicity. The surface is then modified by laser irradiation with various power and scan speed to control quantity of released -CF_3 group. Contact angle decreases with the increasing of irradiated laser energy from 110° to 40°. The quantity of the released -CF_3 group is evaluated by X-ray photoelectron spectroscopy (XPS) and the result indicates gradual decreasing of the group. Its trend is well corresponding to the decreasing of the contact angle. Transmittance of visible light and surface morphology observed by SEM are not changed by the laser irradiation, therefore it is indicated that there is not physical damage during the modification. The proposed modification is applied to surface channel drawing by laser and purified water selectively expands within the modified area.

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Atomic force microscope (AFM) has been widely used as a tool, not only for the measurement of surface topography and the characterization of localized surface properties at nanometric scale, but also for nanolithography and nanostructure fabrication. In this paper, we propose a novel nanofabrication technique for a wide variety of polymer-based materials such as biomolecules (DNA, protein, etc.), living cells, and engineering plastics based on highly localized photochemical oxidation with a TiO_2-coated AFM tip. As a fundamental study, we optimized deposition conditions for preparing single phase anatase TiO_2 thin films by a sol-gel method and by anodic oxidation of sputtered Ti thin films. The photocatalytic decomposition of fluorescently labeled DNA molecules immobilized onto a TiO_2 substrate can be performed under UV irradiation. Moreover, the photocurrent originated from the photoelectrocatalytic oxidation of DNA molecules can be detected. We also demonstrate the ability of a TiO_2-coated AFM probe to perform highly localized photochemical oxidation of organic compounds.

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To date, a number of useful techniques for nanolithography and nanostructure fabrication based on atomic force microscope (AFM) have been studied and developed; they include mechanical modification, local anodic oxidation (LAO), and metal-assisted chemical etching of germanium (Ge) surfaces in water by using platinum (Pt)-coated AFM tips. However, the use of a catalytically active AFM tip for material removal process for silicon (Si) based on chemical etching strategy was never reported before. We propose a novel nanofabrication technique for Si based on highly localized chemical catalysis with a Pt-coated AFM tip. Nanoscale grooves can be fabricated on a Si surface at room temperature via Pt-assisted catalytic chemical etching in just water without adding any chemicals. In the process, we found that dissolved oxygen present in the water must be a key element to drive the chemical reaction of Si with water. In addition, the oscillating cantilever must be required to overcome oxygen mass transfer limitations.

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Every material has sensory features, such as coldness, softness, and heaviness. We define "Void materials" as unrealized materials involving untouched combinations of sensory features, such as "cold and soft". We proposed a methodology to find Void materials in a multi-dimensional space of the sensory features. To confirm the existence of Void materials, we virtually synthesized different combinations of visual, tactile, and weight using a half-mirror apparatus that we developed in our previous study. We asked participants to answer material cognitions of synthesized samples regarding all combinations of aluminum and PMMA in the shape of cylinder. From the experiment, the participants frequently found Void materials in the combinations involving acryl-like features in touch and metal-like features in sight or weight. Moreover, participants preferred synthesized material involving transparent, high thermal conductivity and heavy weight as characters. These results suggest that proposed method can compose favorable Void material by synthesizing combinations of existing materials.

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Quantitative relationship between Kansei and physical quantity is necessary to design Kansei Quality. In general, such relationship is obtained from sensory evaluation with participants. Number of samples that participants can evaluate is limited. Thus, efficient experimental design under limited number of samples is required. In this study, we consider prior estimation of experimenters and past experimental data. We adapted QFD matrix to obtain experimenter's prior estimation or intuition and combined design parameter using the matrix. We apply Bayesian Statistics to integrate the prior estimation. We used hierarchical Bayesian model to model individual variation of regression coefficients, which often occur in human Kansei. We modified Kernel density estimation to construct confidence index for regression function in consideration of function sensitivity.

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A product form that consumers perceive as attractive is currently being developed by architects and designers based on their experience and intuition. To design a product form that is aesthetically appealing to the consumers, it is necessary to understand the process by which humans process information relating to aesthetic sensibilities, including unconscious processes. This study aimed to elucidate the cognitive and neural processes relating to aesthetic sensibilities vis-a-vis product forms, using subjective evaluations and brain function measurements. Electroencephalogram (EEG) measurements were performed while the participants were fixated on an image of a product (the front mask of a car) and were aesthetically evaluating the product form (cool, cute, or beautiful). Participants also evaluated the subjective impressions of a product form, using a variety of adjective pairs. We showed that the process of information processing differed for each aesthetic evaluation of a product form (cool, cute, or beautiful). Since activities were observed in the prefrontal area immediately after the image of a product was shown, it was suggested that the participants were cross checking the product form with their own evaluation criteria from the early stage. The findings of our study have shown the possibility that design elements of an attractive product form may be understood from cognitive and neural processes.

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In recent years, the way to alleviate the disease by using of music that is so-called music therapy, has become popular in Japan. The music therapy is a therapeutic pedagogical technique which is carried out towards the recovery of cognitive and emotional disorders by using of music. Due to awareness of health in the super-aging society of Japan, demands for music therapy is increasing. However, it is difficult to appeal a preference of music for patients who have disorder of speech. Therefore, objective measurement method of emotion, like a measurement method of brain activity, is necessary for provision of music that fit each patients. In this paper, we conducted analysis of brain activity by using of Near-infrared spectoroscopy during listening to music. In our experiment, subjects listened to six kinds of music that combined various tempos and keys. The result shows that each combination of keys and tempos caused different brain activity. It reveals that emotions during listening to music can be identified by using of brain activity.

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Recently, view point of service has been widespread. In learning domains, service providers have been required to adopt it and to provide values co-created by teachers and learners. The current study aims conceptualization of learners states extracted from utterance contents agreed by a teacher (mentor) and a leaner along with conversation analysis in the previous study. As a result, we proposed ontological descriptions which clarify ASIS/TOBE states perceived by teachers and learners.

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For the quality assurance of design and development of suspension with inerter, we performed the validation of 1DCAE with uncertainty modelling through ASME V&V 10-2006 Guidelines based on V-model with V&V. Especially, an example of an assessment process for an behavior of real inerter, that composes bowl screw and some bearing. In this paper, we reported about obtained knowledge and discussed through an assessment process of the validation based on V-model.

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This paper shows analysis of safety requirements for automated vehicles from System of Systems (SoS) perspective using SysML and assurance cases. Interactions among automated vehicles, other constituent systems and environments are very important for realization of the safety. The SoS architecture described with SysML are analyzed using assurance cases to derive the safety goals for each actor of constituent systems. Finally the safety requirements for automated system are derived and the relationships among the safety goals and constituent systems are shown.

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In this paper we describe a system model to clarify the relationship among frequency transfer characteristics and the design parameters. By using SysML (Systems Modeling Language) the system architecture of a mirrorless interchangeable-lens camera is modeled from the view point of its shutter sound. Parameters that affect the frequency transfer functions related to input-output of each component for the system are clarified from the parametric diagram. Through considering the design procedure that includes verification of the architecture from the different design views, the sound quality target is achieved utilizing simulations efficiently.

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When a train travels through a tunnel with a high speed, a compressional wave is generated in the entrance of the tunnel. The compressional wave, which reaches the tunnel exit, causes the noise problems. The formation of this compressional wave can be predicted by using Computational Fluid Dynamics on Body-fitted grid, but this method requires high computational cost. Therefore, this study proposes a CFD on Cartesian grid using virtual flux method. In this paper, for the first stage of this study, we evaluated accuracy of the numerical simulation on the formation of compressional wave in a tunnel when a train running at Mach number of 0.2 enters the tunnel on 2-dimensional Cartesian grid, by comparing pressure variation at an inside of the tunnel with the presence of a tunnel entrance hood. As a result, we report that this method can simulate the tendency that the tunnel entrance hood can suppress a pressure rise. However the simulation overestimates the pressure rise, because of 2-dimensional simulation. To predict the compressional wave more accuracy, we need to analyze with this method on 3-dimentional simulation.

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Rail squats are surface initiated rolling contact fatigue cracks due to the repeated passage of the train wheels. At first, they propagate inside the rail head at a shallow angle to the surface, which are called horizontal fissures. When the cracks reach a certain length, they start to form branched cracks at steep angles relative to the surface. Even after the branching occurred, horizontal fissures continue to grow near the rail surface. Branched cracks, which are called transverse fissures, can lead to catastrophic failure if they are left to grow. It is difficult to find a transverse fissure in the standard ultrasonic flaw detection technique owing to the presence of shallow angled cracks. Therefore, numerical prediction of critical crack size and crack growth rate is an essential to prevent rail from failure and develop cost effective rail maintenance strategy. In this paper, simulation of simultaneous propagation of horizontal and transverse fissures in rail squats has been performed by using Boundary Node Method and Boundary Element Method.

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Vehicle following model is very effective for increasing the traffic capacity and enhancing the traffic safety. This paper describes the vehicle velocity control model of the four-vehicles through intersection. Traffic flow simulation of four LEGO Mindstorms is performed. The experiimental result is compared with the simulation result in order to confirm the validity of the model.

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When the earthquake occurs, the vehicles near shore should move to inland quickly. The algorithm to determine the effective escape route for vehicles is presented in this study. The traffic amount is maximized by changing the escape route of vehicles. Tobishima pier at the port of Nagoya is considered as the object domain under consideration. At the different vehicle density, the escape route is determined. The results show that the present algorithm can find the adequate route.

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In order to reduce accidents with pedestrians or bicycles, hazard anticipatory driving system has been proposed for situations where pedestrians cannot be detected directly due to occlusion. Since a vehicle with the system decelerates to prepare for the undetectable pedestrian at every blind corner, the frequency of deceleration is increased by the hazard anticipatory driving system. Therefore, adverse effect on traffic flow is a concern. This study aims at quantitative evaluation on the effect of the vehicles equipped with hazard anticipatory driving system on traffic flow when they are mixed with vehicles without the hazard anticipatory driving system. This study focuses on traffic capacity as the evaluation index of traffic flow. The traffic capacity is calculated with simulations using a vehicle tracking model and the hazard anticipatory driving system.

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Driving simulators have many benefits as exemplified by easiness of securing safety and repeatability. Therefore, they have been used for driver training and vehicle development. High sense of reality, that is, a sense that one is driving a real car is required for a driving simulator. If the sense of reality is poor, it is difficult to reproduce the operations that subject drivers do with real cars. Therefore improving the reality of driving simulators has been demanded. To improve the reality of driving simulator, researches for improving body sensory information and visual information have been promoted. Stereoscopic technology is currently being focused on because it gives information about depth of space by binocular parallax. However, studies using stereoscopic technology in driving simulator have not been done much. This study focuses on the stereoscopic technology, and investigates the effectiveness of the stereoscopic technology for driving simulator by experiments. As a result, in terms of distance recognition, primacy of 3D images over 2D images was not confirmed in conditions of experiments conducted in this study. However, it was confirmed that 3D images make it easy to perceive anteroposterior movement of objects under certain conditions.

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It is quite important, in industrial communities, to design devices in order to let them have required capabilities. In the design process, we sometimes use the topology optimisation, which is considered as the most flexible computer-aided design method. For the topology optimisation in wave problems which is defined in infinite domain, the boundary element method (BEM) is considered as the most suitable numerical method because of its capability of dealing with the infinite domain. Since the numerical complexity of the BEM is at best O(N^2), where N is the degree of freedom, the BEM is required to be combined with an acceleration technique. As one of the most accepted acceleration techniques, we usually use the fast multipole boundary element method (FMBEM) whose computational complexity is O(N log^α N) with small α. In the FMBEM, an algebraic equation Ax=b is solved with an iterative solver in which matrix-vector products are carried out with the fast multipole method (FMM). It is, however, not appropriate to use the iterative-solver-based FMBEM for the optimisation problems since, in the optimisation problems, it is required to solve two boundary value problems (BVP), called the forward and the adjoint problems. Hence, in this study, we utilise a direct-solver-based FMM to solve the BVPs, in which the coefficient matrix A is compressed with an algebraic method. We show that the proposed direct solver can effectively compute the topological derivative in the optimisation process and can solve a topology optimisation problem for 2D acoustics with the impedance boundary conditions.

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In this paper, we propose a design method for carpet cloaking devices. The carpet cloak is a technology to hide a bump on a semi-infinite boundary by arranging cloaking materials arounde the objdect. We apply a topology optimisation to the design problem of carpet cloaking devices. The topology optimisation is the most flexible configuration optimisation method, which enables us to find an optimal configuration based on mathematical vertification. In the topology optimisation the finite element method is generally used. The FEM, however, takes a lot of numerical costs to generate a mesh and cannot treat an open domain strictly. From these points of view, the boundary element method (BEM) can be said more suitable for the topology optimisation for carpet cloaking devices. In the BEM, mesh is generated only on the boundary and open domain can be evaluated exactly. We show a numerical example of BEM-based topology optimisation for carpet cloaking devices. From the result, we confirmed the efficiencly of the proposed method.

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The aim of this research is to construct a design methodology of a heat control device that has recently attracted attention in the research filed of electric devices. The heat control device is typically employed to control the temperature distribution of an electronic board on which various electric devices, e.g., the transistor and diode, are intricately put. For the appropriate evaluation of the heat control devices, previous study [Ercan M. Dede et al (2013)] proposed performance indexes, the so-called focusing and cloaking. The aim of focusing is to concentrate the heat flux to a target region on the electric board. On the other hand, the aim of cloaking is to avoid the influence of an obstacle that disturbs the temperature distribution. To radically improve these performances, we propose a topology optimization method for the design of highly efficient heat control devices, in which the performances of focusing and cloaking are maximized as the objective functional in the formulation of the optimization problem. In addition, we further define a new objective functional, the so-called uniforming, which aims to uniform the temperature distribution at a target region on the electric board. Based on the above formulations, we construct the optimization algorithm, in which the governing equation of heat conduction is solved using the finite element method, and the design sensitivities are derived based on the adjoint variable method. Furthermore, we use a level set boundary expression for completely eliminating grayscale in the optimal configurations [T. Yamada et al. (2010)]. Several numerical examples are provided to demonstrate the validity of the proposed method.

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To realize a topology optimization based on the Adaptive System as a general optimization framework, the APBA(Adaptive Plan system with Bat Algorithm) has been developed by converting the Genetic Algorithm of APGA(Adaptive plan system with Genetic Algorithm) into the Bat algorithm of Nature-Inspired Approaches as a global search. For first trial of a feasible study, we optimized a mean compliance by embedding a topology optimization of a mechanical structure in the APBA. As a result, the topology similar well to the analysis solution of Michell truss problem was obtained as an optimal topology of a cantilever. This paper describes these results which were obtained via using the APBA.

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This paper presents a numerical solution to shape identification of unsteady natural convection fields to control temperature to a prescribed distribution. The square error integral between the actual temperature distributions and the prescribed temperature distributions in the prescribed sub-boundaries is used as the objective functional. Shape gradient of the shape identification problem is derived theoretically using the Lagrange multiplier method, adjoint variable method, and the formulae of the material derivative. Reshaping is carried out by the traction method proposed as an approach to solving shape optimization problems. The validity of proposed method is confirmed by results of 2D numerical analysis.

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Graphene sheets (GSs) have been supposed to be a base material for nanoelectromechanical systems (NEMS). In this study, we carry out the shape optimization design of GSs to improve their stiffness for applications. According to the Tersoff-Brenner force field theory and a link between molecular mechanics and solid mechanics of C-C bond, we model GSs as continuum frame structures at first. Then, we optimize the shape of the atomistic finite element model based on the free-form optimization method for frame structures. In the optimization process, we use the compliance as objective function and minimize it under the volume constraint. We assume each equivalent continuum beam to vary in the off-axis direction to the centroidal axis and derive the shape gradient function for determination of the optimal design velocity field. Hence, the optimum shape of GSs can be determined without shape parametrization using the derived optimal design velocity field. The results show that, the compliance of GSs can be significantly reduced using the free-form optimization method, which would be helpful for designing GSs for the application in NEMS.

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In this study, we intend to propose a shape optimization method for elastic buckling load maximization of a frame structure. The 1st buckling load factor is maximized under a volume constraint. The problem is formulated as a distribute-parameter shape optimization, and the shape gradient function for this problem is theoretically derived using the Lagrange multiplier method, the adjoint variable method and the formulae of the material derivative. The derived shape gradient function derived is applied to the free-form optimization method for a frame structure, a gradient method in the Hilbert space, where the optimal shape variation is calculated as the displacement field of the linear elastic of the fictitious frame structure. We use the H^1 gradient method for frame structures, in which the nodes can fluctuate and the design flexibility is not restricted. The proposed method, the optimal free-form arbitrarily formed frame structure can be obtained without any shape parametrization. Hence, the problem of large-scale search design space by increasing design variables can be settled and it is possible to determine the optimal shapes with non-parameter. The repeated eigenvalue and Euler buckling of each member are also considered. The results show the validity of this method to determine the optimal free-form of a frame structure for the elastic buckling design problem.

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Spot welding is widely used for manufacturing sheet metal structures such as automobiles. This paper presents an optimization method for determining the welding positions. The spot welding is assumed to be movable in the in-plane direction of the sheet metal structure, or the tangential direction to the plate surface. The squared error norm of maximum principal stress around the spot welding is defined as the objective functional. The optimization problem is formulated as a distributed-parameter shape optimization problem, and the shape gradient function is derived for this problem using the material derivative method. The optimal position is determined by applying the shape gradient function derived to the H^1 gradient method. We confirm the proposed method is effective for designing the welding position of sheet metal structures through design examples.

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In this paper, we propose a robust shape optimization method for a linear elastic structure with unknown loadings. The concept of principal compliance for minimizing the maximal compliance in the unknown loadings is applied to a shape optimization problem of a linear elastic structure. The principal compliance minimization problem is transformed to the equivalent maximization problem of the fundamental eigenvalue, and the problem is formulated as the distributed-parameter shape optimization problem based on the variational method. The derived shape gradient function is applied to the H^1 gradient method to determine the optimal shape variation, or the optimal free-form of the linear elastic structure. With this method, the optimal shape can be obtained without shape parameterization, while maintaining the surface smoothness. It is confirmed that the obtained shape has high and uniform stiffness in all directions. We confirm the proposed method is effective for designing the robust shape with high stiffness of a linear elastic structure with unknown loadings.

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With reference to the Sea deep water jack-up off shore platform, designs an experimental model of offshore platforms. Modal experimental system is developed, the vibration mode experiment of similar model is done. TMD design of tuned mass damper (TMD) for damped linear structures has attracted considerable attention in recent years. Some approximate expressions of optimal tuning ratio of a TMD attached to a damped linear structure have been proposed tuned mass damper (TMD) has been extensively used in vibration control of engineering structures.Experiment results show that TMD can greatly reduce the response of elastic structures under wind, water waves, and earthquakes. Vibration experiment of a offshore plant modeled as a single-degree-of-freedom (SDOF) system subjected to the 1940 HACHI-NS earthquake vibration. It is demonstrated that TMD can reduce the peak displacement effectively. The current study also shows that the TMD performs well in a low-intensity earthquake,in which the TMD is inactivated due to friction.

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The low frequency vibration and noise plays a great effect on human's health. In this study, we used of vibrating table and vibrating insulating box to design experiments on measuring of low frequency vibration noise beyond of human's earshot. And with the measured results we analyzed the characteristic of the low frequency vibration.

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In hybrid or electric automobiles which is environmentally-friendly, noise induced by an engine is decreased, but road noise has relatively come to stand out. Damping sheet and sound-proof materials are widely used in multi-layered structures to suppress vibration and noise in automobiles. The number of combinations of multi-layered structure are too enormous to calculate all combinations. Therefore, this paper calculates efficiently for lighter and better sound proofing efficiency multi-layered structures than existing multi-layered structures. Finite element method to agree quantitatively with the experimental results is used to calculate vibration, but it takes a very long time to calculate the analysis results. We employ transfer matrix method that is shorter time than finite element method. In transfer matrix method, multi-layered structures are expressed by transfer matrix using Biot's model to analyze efficiently. Lighter and better sound proofing efficiency multi-layered structures were efficiently calculated by using a multi-objective genetic algorithm having four objective functions that are mass per unit area, sound pressure level, transmissivity and absorption coefficient.

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Improvement of the quiet performance of the car is an important factor for comfortableness. In particular, Running vibration influences ride quality. There are two solutions of this kind of vibration. These are vibration damping effect by damping material and vibration suppression because of stiffness enhancement by structural material. On the one hand, reduction in weight of vehicle is also required from the point of view of the environmental performance. For this reason, damping and structural materials shouldn't be used more than necessary. Appropriate material arrangement becomes important. The body structure which makes the vibration attenuation effect maximize has been developed without sacrificing quiet performance and roadholding ability by the body weight saving. Propagation of vibration to compartment of the car is suppressed by using damping frame structure which consists of damping and structural materials. The weight saving, usability enhancement, noise and vibration reduction effect are made possible by damping frame structure. The purpose of this study was to build Multi-material topology optimization of damping and structural materials for improvement of vibration suppression effect.

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In Magnetic Resonance Imaging (MRI) apparatus, pulse current is energized to the gradient coils in a strong static magnetic field generated by the static magnetic poles. Since electromagnetic force (i.e. Lorentz force) is generated in the gradient coils, the MRI magnet system vibrates. On the other hand, vibration of the MRI magnet system is affected by electromagnetic force caused by static magnetic poles vibration. As the vibration of MRI magnet system causes magnetic field disturbance (so-called "error magnetic field") and affect image quality, it is important to evaluate them in the design process. In this study, a varying magnetic field evaluation method for MRI magnet system was developed. Vibration and electromagnetic force is considered in the weak coupling formation using the Modal Magnetic Dumping (MMD) method. In the eddy current analysis by vibration, the displacement was considered in the magnetic field changes in the finite elements. Error magnetic field caused by equipment vibration was obtained by superposition of the static magnetic field fluctuation and the eddy current magnetic field. The open type MRI magnet was evaluated by the proposed methodology. As a result, vibration of static magnet poles were suppressed by magnetic dumping at 50Hz or less and eddy current magnetic field was dominant at 50Hz or more.

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A multiobjective optimization method considering uncertainty such as a reliability-based multiobjective design(RBMO) is useful for huge or complicated design problem considering uncertainty such as aerospace structures. In RBMO, the reliability constraint is evaluated through the reliability analysis such as the first order reliability method (FORM). The reliability analysis generally requires the probabilistic distribution parameters of random values such as material properties or applied loads. For example, the FORM converts the probabilistic distribution into the standardized normal distribution. However, under the actual design conditions, it is sometimes difficult to estimate the probabilistic parameters with high accuracy because of lack of information such as the limited number of experiments. In that case, the distribution parameters also have considered as uncertainties that can be evaluated through the confidence level. Then, this study proposes the distribution parameter estimation method considering uncertainties. This study addresses to investigate the effect of the parameter uncertainties on the RBMO using the confidence interval of Pareto solutions.

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This paper provides method of an elasto-plastic analysis for practical seismic design of nuclear piping system. JSME started up the task to establish method of an elasto-plastic analysis for nuclear piping system. The benchmark analyses have been performed in the task to investigate on method of an elasto-plastic analysis. And our company has participated in the benchmark analyses. As a result, we have settled on the method which simulates the result of piping exciting test accurately. Therefore the recommended method of an elasto-plastic analysis is shown as follows; 1) An elasto-plastic analysis is composed of dynamic analysis of piping system modeled by using beam elements and static analysis of deformed elbow modeled by using shell elements. 2) Bi-linear is applied as an elasto-plastic property. Yield point is standardized yield point multiplied by 1.2 times, and second gradient is 1/100 young's modulus.Kinematic hardening is used as a hardening rule. 3) The fatigue life is evaluated on strain ranges obtained by elasto-plastic analysis, by using the rain flow method and the fatigue curve of previous studies.

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Due to design complexity in manufacturing industries, simulation data by parametric study like DOE and optimization includes many kinds of parameters that are design variables, control parameters, requirements, targets, constraints, conditions, so on. In order to make reasonable decision making from those simulaton data, interactive, intuitive and visual data analysis tool is required and inpires design thinking to assume and find new types of combinations of parameters.

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Ground-penetrating-radars (GPRs) are used for surveying underground-buried objects. Methods for estimating buried objects can be classified into two categories. Non-parametric methods are, firstly, employed so that rough sketches of buried objects is reconstructed where no models with buried objects are used. The rough sketches inform us the buried object models. Next, based on the formulas of the model, parametric methods are employed so that parameter values of the models are estimated. In this paper, the authors proposed a method for 2-D reconstruction of upper surface contours in the vertical section of buried objects as a set of line elements. The proposed method is based on multi-bistatic B-scope images being recorded under multiple transmitter-receiver offsets. The line elements are obtained based on the condition that multiple ellipses provided by the different B-scope images touch internally: the ellipses are defined by a constraint deduced from time-of-flight information in B-scope image. Furthermore, the effectiveness of the proposed method was confirmed through a laboratory experiment: using a non-linear least-squares method, position and radius of a buried object were estimated from the contour line elements reconstructed by the proposed method.

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Stochastic resonance (SR) is an effect caused on non-linear systems and enhances signal sensitively through an adequate external noise. Since it is well known that non-linear neuron models have a capability to generate SR, we comprise a parallel network of artificial neurons formulated by Hodgkin-Huxley. A series of numerical simulations were performed through changing number of neurons 1 to 1000. Calculated results demonstrated that increase of neuron number enlarges region of noise intensity capable of causing SR and that noise having independent noise history enhances SR effect.

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Since the confidence of psychophysical experimental result depends on human subjects' mind, evaluation of concentration degree is important to enhance reliability of the experimental result. In this paper, we evaluate the concentration degree using brain machine interfaces such as electroencephalogram (EEG), near infrared spectroscopy (NIRS) and hemoencephalography (HEG). In our experiments, human subjects perform a small object manipulation task using limited visual information on a screen and a tactile mouse with or without tactile sensation. Among these three interfaces, NIRS provided the best evaluation for brain activity appeared by the object manipulation task.

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This paper describes a wire tension sensing mechanism for wire-pulley drive system. In the mechanism, steel wires (φ0.45mm, 100〜150mm long) were periodically excited, and then, the tensions of the wires (5〜50N) were measured by their resonance frequency. By applying square-wave electromagnetic pulse (On-timelms, 10V_<p-p>, offset +5V), the wires were successfully excited. When applied tension was changed in the range of 5-50 N, resonance frequency of 150 mm and 100 mm long wires changed 230-670Hz and 60 to 1000 Hz, respectively. A microphone was conducted to detect the vibrations of the wires. The 150 mm wire generated a sharp resonance peak with a sound pressure of 18dB at 50N tension. In the case of 100mm long wire, the sound pressure level was about 10 dB when applied tension was smaller than 30N. The resonance peaks of multiple wires was able to be separately detect by a microphone, indicating that tensions of multiple wires can be monitored by this sensing method.

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We have developed a wearable tactile sensor using a PVDF film, which detects skin-propagated vibration based on the mechanical interaction between the fingertip and the object. The sensor allows users to touch the object with bare fingertips. The output from this sensor involves in each user's skin mechanical properties as well as touch object and behavior such as contact force and scanning velocity. The sensor has a potential of the evaluation of individual tactile sensations and tactile communications. In this paper, influence of the contact force on the sensor output is investigated. The result shows that the contact force affects the intensity and frequency response of the sensor output.

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This paper addresses a novel assist paradigm for cooperative tasks by multiple operators. The assist is based on Concern For Others: CFO defined as the difference between t of input command of a cooperative task and of the solo task with same manner. The input command in the solo task is estimated by human model with recurrent neural networks. Thus, the CFO can be measured in real time during the cooperative task. In this paper, the quantification technique for CFO is proposed and the validity of the CFO is verified.

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Power-assist robots are useful for physically weak people such as elderly people. On the other hand, in the case of elderly person, not only physical ability but also cognitive ability such as sight or hearing is often deteriorated. For this reason, they might get injured in the accident. For example when they try to sit down on a chair which is not located in the proper position, they fall down. In this paper, the perception-assist method is proposed for sitting motion. In the proposed method, the lower-limb power assist robot detects the position of the chair and estimates user's motion intention. When the chair is not located in the proper position and the user is sitting down movement, the robot assist to avoid falling down by adding the additional force to change the user's posture to the safe posture.

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The objective of this study is to develop a novel mouse device that can present slippages to fingertip skin, named "active wheel mouse": it is a mouse that embodies an active wheel being rotatable in any directions, with any speeds and duration times. As a fundamental study, we examined slippage-perception characteristics by the use of cutaneous sensation on finger-pad: the slippages are induced by wheel rotations. Especially, towards the improvement of the perception characteristics, we examined an edge effect by changing the thickness of the wheel and a slip-and-shear effect by attaching a thin sheet between the wheels and the finger-pad skin. As the first step to optimize the edge effect and the slip-and-shear effect, a preliminary psychophysical experiment was conducted. As a result, we could not clarify the edge effect and the slip-and-shear effect on the perception of lengths and angles.

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This paper deals with a study on the intelligent cooperation control system with human operators. Especially resilient cooperative system in the case of the unexpected damage to the system devices is discussed. The remote operation of the robot arm by human operator are considered as a simplified resilient system. In the experiments, the operator controls the robot arm while viewing the monitor. Suddenly, only auditory information without looking at the monitor situations are happened. Subjects make a scene to operate the robot arm with only auditory information. After studies, operation with the auditory information feedback will be effective.

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