We made the open well biochemical analysis system using piled up Carbon nanotubes (CNTs) as the reaction fields on a porous glass substrate. The effects of the structures of CNTs and the surface activation using 02 plasma to the sensitivity are evaluated. In this study, the reaction fields of CNTs piled up layer of 0.2 [mg] showed twice higher sensitivity than that of 0.1 [mg], and three times higher sensitivity than reaction fields of plane Si wafer. 02 plasma irradiation after making the CNTs reaction fields also increased the sensitivity of this open well system of biochemical analysis. These increases mean more absorption of proteins on the CNTs reaction fields, and that can be caused by the larger surface area of CNTs and the activation of CNTs surface.

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In the conventional sensor using localized surface Plasmon resonance, the metallic particle has only allocated on substrate in two dimensions. We attempted that Gold nanoparticles allocated on the substrate in three dimensions were fabricated by growing CNTs on the Si substrate by the CVD method, and modifying gold nanoparticles by the PVD method. Concretely, we fabricated High density and low density CNTs on the substrate by the CVD method, and modified gold nanoparticles to each CNTs by thermal deposition and vacuum deposition. Evaluation of applicability to bio-sensor was carried out by using protein absorption. BSA of 0.1g/1 as a protein was applied to the absorption test. Absorption spectra of before and after were compared by the LSPR analysis. After BSA adhesion, a spectrum shift to the infrared region was seen in low density CNTs that gold nanoparticle was modified by thermal deposition.

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We propose a long-term cell culturing device for controlling the micro-environment, and evaluate cell proliferation potency in the selective change of chemical/physical conditions. The conventional studies about the cytotoxicity have evaluated complex effects with these chemical and physical factors such as the channel material, the cell concentration, the channel dimension, the pressure and the flow rate. So, it has not been individually clarified that each chemical/physical factor affect the proliferative capacity of biological cells. In this study, we evaluated the proliferative capacity of biological cells affected by each chemical/physical factor by controlling the micro-environment using the proposed portable microdevice. The proposed device integrates a portable perfusion system composed of a culturing channel, a micropump with batteries, and a reservoir for replacing and storing culture medium with suspended cells. It was confirmed that the proposed device selectively controls the physical and the chemical factors due to high portability and controllability by minimizing the dead volume.

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Microfluidic devises fabricated by polymer MEMS (Micro Electro Mechanical Systems) technology have been widely used in interdisciplinary field study such as chemical and biochemistry experiments. Especially, the extension to include filtration membranes in microfluidic devices attracted biophysicists and bioengineers because filtration is an important step in bio-applications. Thus, the authors proposed the epoxy-based filtration membrane fabricated by only 3D photolithography process. This paper describes mechanical properties such as the elastic modulus and hardness of epoxy-based chemically-amplified negative resist, e.g. SU-8 or TMMF (hereafter photoresist) toward a design of nano-filtration membrane made of semi-cross-linked photoresist. So far, many dedicated experiments have been conducted on the characterization of mechanical properties of highly polymerized photoresist. However, the mechanical properties for semi-cross-linked photoresist have not been investigated, and not evaluated in terms of the cross-linked ratio which is the index of the membrane permeability. In the present experiments, a 30 gm thick dry-film type photoresist (TMMF, TOK Co., Ltd.) was employed for sample fabrication, and the indentation test was conducted by DUH-W201 (Shimadzu Cooperation). The elastic modulus for the membrane varied from 4.3 GPa to 4.9 GPa according to the cross-linked ratio of 0.5 to 0.75. Furthermore, it was confirmed that the mechanical properties have obviously correlated with the cross-linked ratio.

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We have fabricated the high aspect ratio X-ray grating for X-ray phase imaging. In past study, we used X-ray lithography technique. However, it is very high cost to obtain the high aspect ratio X-ray grating. In this research, we discuss the new fabrication process of X-ray grating using ICP-RTE technique. Si dry etching technology makes it possible to fabricate high aspect ratio rectangular structures by repeating two steps of etching process and protection process. Therefore, our research introduces the ability of Si dry etching technology in order to fabricate un-tapered, high precision Si microstructures containing rectangular patterns. Au absorbing part for the X-ray grating was formed by electroforming. In order to obtain the high aspect ratio structure, Au electroforming was realized from the bottom of the structure groove. These resulted in the successful formation, about 20 .tm thick, void-free Au film in a space as narrow as 2.6 I..tm in large effective area of 60 mm squares.

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As development of micro-electro-mechanical-systems (MEMS) technology, microforming is gaining attention because of some advantages such as material and structural flexibility, low prices, and high production rate. Heat assisted microforming not only the improve material formability and the tools life but also decrease the energy consumption because the heat capacity is very small in microforming. However, the forming accuracy is decreased by heating tools and equipment. Therefore it is necessary to satisfy the energy efficiency and the forming accuracy for practical stage application. We designed the heat assisted microforming equipment with resistance heating which is capable of heating only workpiece material without tools. The performances of the equipment were evaluated by measuring the relationship between the temperatures and the energy at different contact conditions with tools. The heat loss energy was also evaluated and considered to the effect of thermal deformation of tools. The drawing tests were carried out and the results showed the equipment is capable to improve the formability at elevated temperatures.

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Shape memory polymers (SMP) have excellent properties including light weight, large deformations, and easy formability to form arbitrary shapes. In particular, polyurethane series SMPs work stably and have the added advantage of being able to tailor the glass transition temperature (Tg) to an arbitral temperature. We applied the polyurethane series SMPs to MEMS actuators. However, for SMP actuators, after the memory shape is formed, it is necessary to return it back to the original shape by some method. We used two kinds of SMPs with different glass transition temperatures (Tgi, Tg2, Tgl<Tg2) and used the memory shape of Tg2 for canceling the memory shape of Tgi by making the memory shapes of Tg2 reverse of that of Tgi. We applied this mechanism to cantilever beam samples coated with SMP layers on the surface. We confirmed that the beam deforms around To and then the deformation disappears around Tg2. Arrayed actuators with unified thin-film heaters are also proposed.

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A microelectromechanical systems (MEMS) combined sensor measuring two-axis accelerations and an angular rate (rotation) has been developed for an electronic stability control system of automobiles. With the recent trend to mount the combined sensors in the engine compartment, the operation temperature range increased drastically, with the request of immunity to environmental disturbances such as vibration. In this paper, we report the combined sensor which has a gyroscopic part and two acceleration parts in single die. Especially, we focused on the structure design of the deformation-robust gyroscope which has three sets of symmetrically arranged folded beams as a main topic. The developed gyroscope has less than 0.6% temperature dependant variation of mode frequencies as well as less than 0.04% variation of the difference between driving and sensing mode frequencies.

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The microactuator that makes electrostatic energy/force collaborate with the elastic energy/force was previously proposed. It had the non-linear leaf spring that was designed to work effectively, and the vertical electrodes that moved horizontally (in parallel to the substrate). We propose the new type of microactuator that has the horizontal electrodes moving vertically to generate more powerful electrostatic energy/force. It is necessary to design vertically movable non-linear micro leaf spring in order to make the microactuator highly effective, and it is also needed to develop the fabrication process which uses gray tone lithography to form the non-linear leaf spring. In this paper, the vertically movable non-linear leaf spring was designed and its characteristic was evaluated by using the FEM analysis. The fabrication process of the vertically movable non-linear spring was developed, and its validity was evaluated, too.

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Silicon dioxide electret induced by highly doped potassium ions will be demonstrated by forming on a comb-drive actuator. The comb-drive actuator made of a silicon on insulator (SOI) substrate is oxidized with bubbling stream of KOH solution to form a silicon oxide film including potassium ions on the etched side-walls of comb electrodes uniformly. After bias-temperature (BT) procedure at about 800 K and 100 V was applied to the device, we have confirmed 40 V built-in potential difference between the opposing comb electrodes. The gradual decay of the potential have been observed, but 35 V built-in potential was maintained even after 1 month.

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It was investigated that the etching characteristics of lead-free (K,Na)Nb03 (KNN) thin films by the ICP-RIE (Inductive Coupled Plasma ・Reactive Ion Etching) with Ar-C4F8 mixture for the reactive gas. The Ar-C4F8 mixing ratio fixed 10:1, and the chamber pressure was 0.5Pa during the etching. The KNN etching depth has linear relationship as the function of the etching time. The etching rate increased with increasing the antenna power and the bias power. The antenna and the bias dependence of the etching rate show good linearity. These linear relationships indicate the good controllability of the etching. The KNN/Pt selectivity increased with increasing antenna power and decreasing bias power. Thus, the high KNN etching rate was obtained at high antenna power and high bias power condition. The high KNN/Pt selectivity was obtained at high antenna power and low bias power condition. The maximum KNN etching rate and KNN/Pt selectivity were 371.6nm/min. and 85.8, respectively. These results are comparable to that of the conventional piezoelectric PZT films.

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The biggest factor of the difference of worked angle is occurrence of springback. To solve this problem, in this study, the ultrasonic-vibration assisted bending was performed on stainless steel foils (SUS304) to explore the springback reduction effect and its size effect of superimposed ultrasonic-vibration during bending. Size of the specimens were 10 X 5mm. Experimental parameters were frequency (1570 9410Hz), applied vibrating time (2s and 5s) and thickness (100pm and 50pm). Experimental results show that according as the frequency increases, springback decrease ratio gets higher. Thus springback reduction doesn't depend on applied vibrating time but frequency. This study also made proposal for mechanism of springback reduction effect from the aspects of compressive force and diffusion of dislocations made by ultrasonic vibration. In the case of thickness 100pm, compressive force produced by the impact loading contributes to springback reduction. On the other hand, in the case of thickness 50gm, diffusion of dislocation contributes to springback reduction. These results show that the higher frequency you use, the more you could decrease springback.

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The plasma is applied to the light source, such as fluorescent lamp. When the wavelength is short in deep UV, LD is difficult to realize. In this research, Si device for atmospheric plasma light source is designed and fabricated. The size of the device is 2x8 mm2, the width of light emitting area is 150 pm and depth of that is 200 p.m. For enhancing the ignition, the floating electrode is designed to be in the micro gas channel. This electrode has the bow tie shaped projection part disturbing the laminar flow. The device is placed near the copper spiral coil, which is connected to 100MHz high-frequency power source via the impedance matching box. When the magnetic field from the coil passes through the patterned metal in the device, the induced voltage occurs. The plasma ignites in the device. The input power is 138W. He gas flow rate is 49.0m1/min.

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In order to improve the quality of life of persons who lost their own limb due to an accident or sickness, many myoelectric artificial arms have been proposed. These myoelectric artificial arms are controlled based on EMG signals. If muscles which are used to move a target joint remain, EMG signals can be measured at the muscles. On the other hand, if these muscles do not remain, EMG signals must be measured at other muscles. In this paper, the control method of elbow joint motion of a myoelectric arm for an above elbow amputees is proposed. The proposed myoelectric arm uses EMG signals of the biceps brachii and the triceps brachii muscles as input for elbow joint motion. However, since both the biceps brachii and the triceps brachii muscles are the biarticular muscles between the shoulder joint and elbow joint, the EMG signals of these muscles are affected depending on the motion of the shoulder joint. To remove the influence of the shoulder joint motion on these EMG signals, a neuro-fuzzy modifier is used in the proposed control method. The effectiveness of the proposed method was evaluated by performing experiments.

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In previous studies, we developed a system composed of an experimental apparatus and a computer program and we have performed a series of psychophysical experiments using the different types of stimulus. The experimental result shows that variation in the difference threshold (Difference Limen; DL) has a local minimum point in the relationship between DL and noise. Therefore, the tactile sensation's just noticeable difference (JND) is decreased by appropriate external noise. Since JND denotes the scale divisions of sensation in the human mind, the present result shows that precise tactile sensations are enhanced by the appropriate external noise. According to the experimental results, we introduce a neural network model composed of nonlinear neurons with the bi-stable equilibrium condition to explain this result. Although original sensor data do not represent the morphology of the fine texture, the neural network model extracts the morphology and distinguishes the wave amplitude of the fine texture.

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In the case of some elderly persons, the environment perception ability is sometimes deteriorated. To assist the daily living motion of those people, power-assist robots with the perception-assist have been proposed. The power-assist robot with the perception-assist assists not only the user's motion but also the user's interaction with an environment, by applying the modification force to the user's motion if it is necessary. The effectiveness of the performed perception-assist is judged by the EMG signals. In this paper, we measure the EMG signals and EEG signals at the same time to observe the features of these signals when users use the power-assist robot. Specifically, in order to use EEG signals as the criteria of the effectiveness of the perception-assist in addition to EMG signals, these signals are observed when the robot performs the perception-assist.

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In order to obtain mechanical condition for generation Velvet Hand Illusion (VHI), which is one of tactile illusions, we investigate VHI using a motorized apparatus to generate passive VHI and Thurstone's paired comparison method. Experimental results show that the strongest intensity of VIII is occurred when the wire spacing almost equals to the movement stroke of two wires. However, strength of VHI is reduced in both of less and larger movement strokes than the wire spacing. Although VI-11 requires mainly compressive stimulus and additional tangential stimulus acts as trigger of VHI, excessive tangential stimulation prevents the occurrence of VHI. Although the tangential stimulus is effective even if it is apart from area applied to compression, VIII becomes the largest intensity when both of compressive and tangential stimuli are applied simultaneously.

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The steering feeling's evaluation of the automobile is evaluated subjectively by the test driver in the every design object, and the technology which can objectively quantify using the physiology index is desired. The purpose of this research is to establish the objective evaluation using the surface myoelectricity for the reaction torque from easiness of the human physiology measurement as the basic technology. In this paper, it is designed collision avoidance warning by the steering torque using myoelectricity measurement.

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In this study, we derive a curvature output type vehicle handling model for the theoretical study of a driver-vehicle system in the lane following driving mode, and the parameters are set using the stability of the whole system as the optimization index. We employ Pade approximants to account for the time delay element in the human model, and the bicycle vehicle model is reduced to a second order system. We determine the gain constant from geometric relations between the vehicle, lane and point of regard. The characteristic equation of the whole system is derived; this equation is rearranged as algebraic relations that correspond to the quintic root of the characteristic equation. The system of equations is solved to determine the parameter values for a given condition. Further, we show the basic characteristics of the model by means of numerical examples for a single lane change.

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This study examines the braking assistance system for train drivers when stopping at a station. The conventional assistance system informs only a predicted stopping position calculated by vehicle velocity and deceleration. The assistance system proposed in this study informs whether the driver can release a brake handle for riding comfort. This assistance system makes the driver aware not only the predicted stopping position, but also the appropriate braking operation. Train-driving simulator experiments are examined with several subjects who are required train driving with mental calculation assumed mental workload. Subjects with the proposed assistance system can stop the train with small deceleration, while subjects with the conventional assistance system cannot stop the train with small deceleration.

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This paper deals with the information presentation interface in a parallel two-wheel vehicle. This vehicle has the feature of integrating with man and moving. Therefore, we proposed for man to change information into the movement of the vehicle, and to tell it. A signature wave was added to change the behavior of the vehicle. Finally, the difference of the recognition rate of an existing technique and the interaction was clarified by the experiment.

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These days, personal mobility vehicles (PMV) for the new individual transportation device are proposed at home and abroad. It is very important to ensure the safety of a PMV especially when a PMV runs in pedestrian flows. In this research, the affinity between pedestrians and the compact PMV of which concept is an extension of walking is investigated using the simulations. The simulation model was built by introducing personal space (PS). PS is the space that creates the psychological strain due to the invasion by others. In order to evaluate the affinity, the invasion ratio that is the original index is proposed. Comparing with the previous experimental results that show the pedestrians' discomfort and fear level by questionnaires, it was shown that the average invasion ratio, the maximum invasion ratio and the crossing time could be the elements to express the affinity. For the derivation of the affinity between PMV and pedestrians, further experiments and PS data acquisition are the future tasks.

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This paper discourse about Nonlinear Finite Element Analysis of the container stack on the carrier deck in storm condition.Now a days many container using for maine transportation, and carrier ship became a large scale to tackle increasing traffic volume. But container stack on the deck is moving by wave, sometimes it clash each other and container brake, stack is disrupted. Using numerical analysis to this problem, research how to behivor container stack and validate by experiment using stack in transporting.

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Recently, the energy-saving driving or "eco-driving" has attracted attention in the research communities. The previous studies on the eco-driving are limited in that they take into consideration own vehicle's statuses and driver's driving behaviors. However, circumstances such as traffic conditions, road alignments or traffic lights should also be considered, because the optimum eco-driving is depend on conditions of both a driver and circumstances. In this work, we propose a quantitative evaluation technique based on probability statistics for the energy-saving driving which takes into account not only own vehicle's statuses or driver's behaviors but also circumstances. This paper mainly describes the outline of a proposed technique.

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An electric vehicle has several distinguishing characteristics. Not only zero emission but also independent, high response and accuracy drive control derived from in-wheel motors is the remarkable point. The right and left in-wheel motors have the capability of driving vehicle even if one side is in trouble. In this paper, we propose the fault tolerant drive control system using steer-by-wire. This control system is able to drive with acceleration and deceleration even if in trouble. The effectiveness of this method has been verified in simulation.

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The direct yaw moment control (DYC) poses an optimization problem for the determination of tire force distribution. One of us has derived an algebraic solution to a minimax optimization problem that is characterized by the requirement of the traction braking force difference between the left and right wheels together with the minimization of the maximum value of tire workloads. In this study, we apply this solution to a generalized optimization problem in which we consider the yaw moment due to the steering of the front and rear wheels. In this formulation, the total value of the moments generated by two different mechanisms is specified. The proposed numerical approach that uses the golden section method rapidly converges and determines the tire force for the four wheels that generates the required traction/braking force, lateral force, and the total yaw moment, and thus the maximum value of the tire workload is minimized. Further, we demonstrate the effect of relaxation of the tire force distribution problem through a numerical example.

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To evaluate driving performances of aged drivers, driving experiments were executed for the elderly drivers with white matter lesions (WMLs) and without WMLs, respectively, in the same ages, and young drivers without WMLs. Before driving experiments, all of them undertook dynamic vigilance checker (DVC) test, a visual cognitive test. In the experiment, as an additional task, paced auditory serial addition test (PASAT), a calculation task given by voice, was imposed on drivers to examine the effect of the additional task on the driving performance. The driving skills were scored by an authorized police examiner, while driving parameters such as the steering angle, velocity of the car were measured by using a controller area network (CAN). The results showed that the drivers imposed with PASAT made more mistakes than when the drivers without PASAT, and scores of DVC test decreased with the growth of ages. Besides, the experiment indicated the possibility to estimate the driving skills by using CAN.

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This paper discribes a investigation of the nonlinear filter which can change a high frequency gain and delaying phase independently. There have been a lot of the investigation of the driver-vehicle closed-loop system. But, even the optimal relationship between gain and phase are not yet found. For example, there is a proper value of the delaying phase in the vehicle dynamics. And when the delaying phase is too small, the driving easiness is reduced. However, generally in a linear system, a high frequency gain becomes larger as phase becomes smaller. It is impossible to define which is the main factor of driving difficulty, gain or phase. So, we tried to change a high frequency gain and delaying phase independently and experimented. Therefore, we applied the nonlinear filter to the driving simulator, and examined a change the subjectivity evaluation of the vehicle maneuverability and the experimental data.

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In this experiment, whether that flexibility of medical treatment and the food can be distinguished was examined. Using the air jet, it was done that the proposal of the method for measuring the flexible thing and the equipment was developed. The experiments were carried out using skin of human being gel and food. By measuring the position and the angle of the inflection point, it was proven that the discriminant of the flexible thing was possible.

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An effective method for sensitivity analysis of uncertain parameters in space reflectors is presented. In the method, the sensitivities of uncertain parameters with respect to structural modes are explicitly derived by utilizing the singular value decomposition of sensitivity matrix, which can predict which modes are excited due to the variation patterns of uncertain parameters. A simple numerical example, the model of which is a radial rib and hoop cable antennas that consists of 60 radial ribs, are provided to verify the effectiveness of the presented method.

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In this study, a system for high-accuracy estimation of surface error properties is developed. In the system, a photogrammetric measurement such as stereo-vision is mounted on a slider and its movement is precisely measured by a laser displacement sensor. Deformations of a target object are measured repeatedly using the photogrammetric measurement at different slider positions. Correction methods of the measurement errors and estimation methods of the surface error properties are derived.

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Design of a very precise space structural system requires an accurate estimation of uncertainties on structural and environmental parameters. For the purpose, high accurate estimations of uncertainties of the structural parameters and the effect of the paremeter uncertainties on the structural response uncertainty are required. Then, the robust design optimization based on the accurate estaimation is required. This study focuses on the former part, a high accurate estimation of the uncertainties. The applicability of a bootstrap method known as a nonparametric technique is investigated to estimate the confidence intervals of the uncertain parameters related to vibration responses of simple structures. The target structure is a cantileverd bow-shaped structure composed of beam and tether that is a breadboard model of a lightweight space reflector. The confidence intervals identified from several numbers of vibration tests is compared by the nonlinear finite-element analysis.

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A method is proposed for solving a set of simultaneous equations with an ill conditioned coefficient matrix to apply system identification. To find an approximate solution, the coefficient matrix is regularized by adding a small positive value e to its diagonal elements. A regularized matrix is provided in different expressions that depend on the coefficient matrix. This paper regularizes a rectangular coefficient matrix and then a square coefficient matrix. Improvement of solution accuracy is possible by removing the very small singular values. Therefore, rank estimation of the coefficient matrix is a key to obtain an accurate solution. This paper describes a method that estimates the rank by setting an appropriate value of E.

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Sensitive plant (Mimosa pudica) is one of the most unique plants, because the petioles moves downward and leaflets unfolds rapidly as response to any mechanical, thermal or electrical stimulus. The folding motion of the leaflet looks like very complicated including twisting motion to overlap each other as making one line for compact spacing. For a design of man-made actuator, therefore, it is quite interesting and useful to understand the mechanism of sensitive plant leaflet motion. In this study, the manner of leaflet connecting to the midrib, the location of pulvinus and the cross-sectional shape of midrib etc. were observed by using various optical microscopes. From the observation, it was found that the leaflets accomplish the complex closing motion by their one-way rotation with the ingenious combination of three installation angles relating to the leaflet, midrib and pulvinus. These are a, /3 and ywhere a is the apex angle of the midrib cross-section, /3 is the angle connecting the pulvinus with the midrib, and y is the angle between the axis of pulvinus and the rachis of leaflet.

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The effects of UV fluence on strength properties of PEEK films were investigated based on tensile tests. Elongation at break clearly decreased with increasing UV fluence although yield strength and elastic modulus were almost same before and after irradiation. Surface observations during tensile tests and fracture surface observations clarified that small cracks with a depth of a few ttm initiated at irradiated surface, and that true stress at which crack initiated decreased with increasing UV fluence. The analyses of chemical structure at UV irradiated surface by using FT-IR method confirmed the increase of carbonyl bonding at the depth corresponding to the small cracks, which caused the embrittlement of the surface layer. Small cracks initiated at the thin embrittled layer propagated and coalesced each other during tensile tests. This phenomenon can be the main reason for the decrease of elongation at break of UV irradiated PEEK films.

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Biaxially stretched films of poly(aryl ether-ketone)'s (PAEK) are manufactured and investigated its properties. Glass transition temperature (Tg) of PAEK resins rise about 25 degC with biaxial stretching which achieves to let them be one of the most thermally durable plastic films. This thermal property provides low dielectric loss tangent (tans) at the temperature of 160-170 degC. Furthermore, the biaxial stretching achieves to obtain very thin films of several microns with enough strength. Taking advantage of these properties, it is expected that special electric devices application (with high energy density) or some structural application in aerospace development activity.

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Polyimide (PI) films have been applied to construction materials for space film structures such as flexible solar arrays and solar sails. In this research, mechanical properties degradation of PI films by atomic oxygen (AO) were experimentally evaluated with tensile tests and predicted with fracture mechanics methods. Then, the experimental values and the predicted ones were compared to confirm effectiveness of the fracture mechanics methods. AO is the main atmospheric components in a low earth orbital (LEO) environment and can erode polymer materials surfaces; polymer materials attached by AO exhibit a rough texture. Tensile strength of PI films irradiated by AO using a ground facility reduced concomitantly with increased AO fluence (FAQ). In the rupture of the PI films, cracks originated from the AO-irradiated surfaces which had rough textures because of AO erosion and grew unstably after a stable growth. The tensile strength of the PI films was calculated with fracture mechanics methods. Mirror regions observed on the fracture surfaces were considered to fracture defects and fracture toughness equations for a strip with a semi-elliptical surface crack were applied in the calculation. The predicted values almost corresponded with the experimental ones. Additionally, in the PI films exposed to the LEO environment, the tensile strength predicted with the fracture mechanics methods was comparable to the experimental data. These results indicated that this method is an effective tool for strength analysis of PI films exposed to a space environment.

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Voids, that could be the origin of fractures in composite materials, are likely formed in between filaments during resin impregnation. To reduce these microvoids, it is important to clarify the mechanism of microvoid generation. In our previous study, we constructed an experimental model using a microfluidic-device in which many pillars have been arranged hexagonally and observed the flow behavior during microvoid generation. Our results showed that microvoid generation correlates to velocity, viscosity of the fluid and geometric distance between adjacent pillars. To evaluate these relationships without cumulative effects arisen from surrounded pillars and random shape of the flow front, we constructed another microfluidic-device in which two pillars are aligned with a distance along the flow direction. Using this simplified experimental model, our results showed that there is velocity criterion in determination of microvoid generation.

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A new testing system for high temperature structural materials and components used for gas turbine has been developed. The system consists of an advanced combustion system and a servo-electro hydraulic material testing system, and it can give thermo-mechanical loadings to a test sample in simulating actual combustion environment. By means of this new apparatus, failure behavior of a thermal barrier coating (TBC) specimen was studied under a condition of cyclic burner heating together with a constant tensile loading. The experimental results demonstrated that the failure behavior was sensitive to the temperature distribution of specimens and to the combustion gas flow. The present testing system would be very helpful to evaluate the damage of the TBCs under in-service conditions close to actual advanced gas turbines engine operation.

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It is impossible to design structures without Young's modulus value. Structures in space is put under low temperature condition around ・70 -C. And when a spaceship returns back to the earth, outer material of the ship is exposed to very high temperature near 1400 -C. Then a design for structures in space needs Young's modulus value over wide range of temperature. We have proposed a method to measure Young's modulus value employing impact sound. The method needs small rectangular specimen, 4x5x50. Putting a specimen into atmosphere filled with liquid nitrogen vapour or heated up by furnace, Young's modulus values on steel, pure cupper and aluminium alloy were measured with ease employing the method over -190-C to room temperature and over room temperature near to melting point temperature of the materials.

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Functionally Gradient Material, FGM is a composite constituted by two components, characterized by a compositional gradient from one component to the other. The strength and functional properties of FGM differ from simple bonded dissimilar material between two different components. In the present study, FGM based on Ni and Zr02 were manufactured by powder molding method and the Vickers hardness tests were carried out. The creep tests were also carried out at about 2100K using the plasma jet equipment. It was shown that Vickers hardness and creep rupture life of Ni Zr02 FGM increase with increasing the sintering time during manufacturing process of this FGM.

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The linear shaped charge is shaped charge using V-liner. The shape charge makes high-velocity metal jet in the shape of a rod, and the metal jet used breaking. The linear shaped charge compared with shaped charge is the metal jet in the shape of linear. Therefore, the linear shaped charge is used as means to cutting and breaking solid rocket motor, geothermal scale and etcetera. In this paper, it was a high-speed photography and cut examination, with a shaped charge of the linear and arc. From the result, generation, a flight and the cutting mechanism were examined. And the Linear shaped charge which laminated a metal plate was developed for metal jet of the arbitrary shape. It was tested in a linear, arc and combination model linear shaped charge. The result shows success for the cutting of the steel sheet, steel tube and geothermal scale.

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Wrinkles and collapse of inflatable tubes have effect on the structural properties. The collapsing process and the deformation of the inflatable tube subject to bending moment are discussed by FEM analyses. The nonlinear properties for the growth of the collapse through the wrinkles on the inflatable tube are examined in detail by both the deflections and the strain distribution of the tube. The result of the load-deformation properties by FEM analysis is good agreement with the experimental result by considering the axial stiffness due to the friction force. Before collapsing, as bending load increases, the amplitude of the wrinkle increase without changing the wavelength of the wrinkle. After collapsing, some large wrinkles are dominated for the deformation of upper part of the tube. Also the configuration of wrinkles for collapsing inflatable tube coincides with experimental result qualitatively.

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We propose a wing which is constructed by two solar cell films and a gas-inflatable beam. The two solar cell films correspond to the upper and the lower surface of the wing, and the beam is putting between the two films. The two films are flat plate before the beam is inflated by gas pressure. After the beam is inflated, the films become like shell with curvature. We produce a prototype wing and perform bending and twist experiment to demonstrate a structural characteristic of the proposed wing. Also, we perform geometric nonlinear finite element analysis based on the plate theory considering shear deformation. As a result, the result of both bending and twist experiment shows that separation of linear part and nonlinear part in load-deflection curve is not clear, and we observe deflection of our wing for the large applied load. Our numerical analysis result correspond to the experimental result.

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The object of this study is to propose the updated design method for the thin-film solar cell panel, and to clarify the influence of heterogeneity of the material of the thin film panel on the proposed design method. We proposed a hinge-less, ultra-light-weight deployable solar array paddle as a functional/structural integrated structure. In the actual solar panel, many functional materials such as solar cell, cover glass, and circuit lines are integrated and laminated. Therefore, we performed a structural analysis to compare structural characteristics of the homogeneous material with that of the heterogeneous material. We found that the actual thin panel is also improved the bending rigidity by giving the curvature, however, the actual panel structure shows polygonal shape in the cross-section area. Consequently, different modes arise in heterogeneous material. We found that, we must carefully consider the influence of the polygonal shape on the vibration modes in the proposed right-weight design method by mode control.

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In SCOPE mission, flexible extendable rod antennas are equipped along the spin axis of satellite. For the extendable function, STEM (Stowable Tubular Extendable Member) is used as the rod antenna. The apparent natural frequency of the STEM changes depending on the spin-rate. Furthermore, bending and torsion of the STEM are coupled because the STEM has open section. The dynamic characteristics of the STEM are clarified through analysis and tests. Especially, the coupled vibration of bending and torsion, and the effect of spin motion on apparent natural frequency of the STEM are investigated. As a result, it was shown that the effect of spin motion can be quantitatively predicted by simple analytical model. In addition, it was found that the characteristics of the vibration are strongly affected by the boundary condition of the STEM.

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The relationship between the stress o and time t of an SUS303 round bar was measured using an intelligent universal test machine. The elasticity plasticity transition point o ・ which was a stress of the boundary of plasticity and elasticity, was obtained by the analysis of the measurement result. As the coordinates of the complementary energy Ec , the horizontal axis shows the load P and the vertical axis shows the deformation 8. Moreover, the analysis of the complementary energy Ec was carried out. The difference in the complementary energy Ec of each stress as a step stress a St was calculated twice. The elasticity plasticity transition point a ep was obtained by this method. A static torsion test on an FCD370 round bar was also carried out. The difference in the complementary energy Ec of the FCD370 round bar was calculated twice similarly to that of the SUS303 round bar. The elasticity plasticity transition point r ep of the FCD370 round bar was obtained.

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Considering space utilization of the fine-grained metals, we have investigated an influence of the nano-scale voids on mechanical behavior of Cu fine-grained metals based on molecular dynamics (MD) method. Focusing on the dislocation activity enhancement due to void growth, grain size and temperature dependence of the mechanical behavior change have been evaluated. MD simulations have shown the following results: (1) Dislocation activity around the void at the initial void growth stage has an influence on the change in yield stress. (2) Dislocation activity enhancement due to void growth during and after yielding conducts increased ductility by improved plastic deformability. (3) Amount of ductility enhancement is larger at low temperature than at room temperature.

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Efect of stress ratio on fatigue properties was investigated for Ni base super alloy 718 forging. Fatigue tests were conducted under stress ratios of R = -1, 0.01, 0.5 and under the condition fixing the maximum stress at 0.2% proof stress (6,,, =Co2 test). The internal fracture occurred in all test condition. The fracture sites of the internal fracture revealed the carbide inclusion and several facets. The fatigue limits determined at 107 cycles were below a modified Goodman line under R=0.01, although they were above under around R=0.5 and 0.7.

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The effect of mean stress or the stress ratio, R, (ratio of minimum stress to maximum stress) on the high-cycle fatigue properties of Ti-6A1-4V extra-low interstitial (ELI) forging was investigated at 293 K and 77 K. Fatigue tests were carried out for up to 107 cycles at stress ratios of R=-1, 0.01 and 0.5, and also under the condition where the maximum stress was fixed at 0.2% proof stress ( Crmax = cr02 test). The high-cycle fatigue strength at 107 cycles decreased at each temperature as the stress ratio increased, when the fatigue strength was evaluated in terms of stress amplitude (aa). In the R=0.01 and 0.5 tests, however, the high-cycle fatigue strength at 107 cycles exhibited deviations of aa below the modified Goodman line at both temperatures, indicating that this alloy exhibited an anomalous mean stress dependency. In particular, the amounts of negative deviations from the modified Goodman line at 77 K were larger than those at 293 K. Thus, it is concluded that the anomalous mean stress dependency of this alloy becomes remarkable at low temperatures.

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