Neutron diffraction is a one of useful technique to measure the residual stress of crystalline materials. The residual stress is that to be left in materials by processing history such as heat treatment and plastic deformation. In the present study, the residual stress of hot deformed bar of structural parts was measured by neutron diffraction.

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Plasma facing materials for fusion experimental devices are required to have high thermal resistance, high thermal conductivity, thermal shock resistance, radiation damage resistance and so on. There are no materials of which properties are sufficient to meet the requirements. Because the plasma facing components are severely exposed to the high heat load and particles with high energy from fusion plasma, the high melting point metal such as a tungsten material is expected as a candidate material. In this study, high energy ions are irradiated to the tungsten joining materials to apply them as an advanced structure material to the next fusion experimental devices. The relationship among the mechanical properties, the microstructures and the effects of radiation damage at the boundary parts of tungsten are made clear by an ultra micro hardness tester, SEM and TEM. And the thermal responses of the tungsten joining materials are also evaluated by electron beam heating tests.

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High strength aluminum alloys are expected as a candidate material of liner materials for high-pressure hydrogen containers. In this study, aluminum alloys of A6061-T6 and A7075-T6 were offered. The Effects of hydrogen on the fatigue properties are evaluated by fatigue tests in air, steam and deuterium atmospheres at 30℃ and 90% relative humidity. As the result, the A6061-T6 aluminum alloy is found to be possible to apply high-pressure hydrogen containers of fuel vehicles, since the increasing rate of the crack growth speed is smaller than that of A7075-T6.

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In recent years, we are paying attention to clean energy because of environmental problems such as the global warming and the exhaustion of fossil fuels. As a way to solve these problems, fuel cell vehicles have been paid attention to because the fuel of the fuel cell vehicle is hydrogen that is one of the clean energy. In the fuel cell vehicles, high-pressure hydrogen gas is stored in a container consisting of aluminum liner and surrounding fiber-reinforced plastic layer. It is only 6061 aluminum alloy that is authorized as a liner aluminum material at present. Since reduction both in the weight and cost is required for the popularization of the fuel cell vehicles, the use of higher-strength aluminum alloy is considered. However, it is known that high-strength metallic materials are prone to suffer from hydrogen embrittlement, the mechanism of which has not been well elucidated yet. For a fundamental understanding of the mechanism of hydrogen embrittlement in high-strength aluminum alloy, in the present study, the behavior of hydrogen invading from the environment have been investigated in a 7075-T6 sheet by means of thermal desorption spectroscopy for specimens tensile-deformed at a low strain rate under air filled with heavy-water vapor. The obtained results have shown that hydrogen invades the specimen up to a deeper region when deformed then when just held in the same environment.

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The use of hydrogen as a clean energy is being highlighted particularly in terms of the prevention of global warming. In this relation, hydrogen fuel cell vehicles have been developed, where aluminum is used as the liner of cylinders for compressed hydrogen gas. For the safety of the vehicle, for the prevention of hydrogen embrittlement of the liner, hydrogen behavior is required to be elucidated. In this study, hydrogen microprint technique, HMPT, has been applied to a series of aluminum alloy containing a single kind of constituent particles, to elucidate the invasion behavior of hydrogen affected by constituent particles as this effect is suggested in some previous reports, particularly in 7075 aluminum alloys. Several Al-Cu-Fe alloys with different fraction of Cu_2FeAl_7 phase, the mail constituent phase in 7075 alloys, have been laboratory-produced into a sheet of about 1mm thickness. Hydrogen atoms permeated from one surface at hydrogen gas of 0.3MPa to the other surface covered with photographic emulsion for HMPT have been observed as silver particles. In Al-11mass%Cu-5mass%Fe alloy, since the hydrogen atoms have been detected only on the Cu_2FeAl_7 particles, hydrogen emission site is confirmed to be only this phase as in the 7075 alloy. However, the emission amount is markedly smaller than in the 7075 alloy, which implies that the other phase consisting of the alloying elements such as Zn and Mg also plays an important role in the process of hydrogen invasion and diffusion.

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As a typical superplastic metallic material, Zn-Al eutectoid alloy has been well known, where fine-grained microstructure required for the occurrence of superplasticity is obtained by solution treatment, water-quenching and subsequent aging at an elevated temperature such as 200℃. Recently thermo-mechanically controlled process (TMCP), where hot rolling is conducted under temperature control, has also been reported to provide a fine-grained microstructure. As the critical cooling rate in this technique is slower than in the above-mentioned traditional process, it can be applied to thick-gage components and product alloy plates have been employed as seismic damper in an actual high-rise building for protection from giant earthquakes. However, condition to obtain fine-grained microstructure and its mechanism has not elucidated yet. Hence in the present study, control conditions in hot rolling such as temperature, total number of passes, reduction in a pass, etc. have been investigated in a Zn-Al eutectoid alloy to obtain fine-grained microstructures. Homogenized ingot specimens were hot-rolled using conventional mill without a heating device from 20 to 2mm in thickness with 9 passes. The specimens were held at 260℃ for 30min before each pass, and water-quenched after the pass. Microstructural observation on the final sheet with 9 passes and that of 3mm thickness with 8 passes showed that equi-axed fine-grained microstructure with grain sizes of about 2μm was observed in the two sheets.

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Gum Metal is a newly developed beta titanium alloy, which has a low elastic modulus, high strength, highly super-elastic characteristics, super-plastic characteristics, Invar and Elinvar characteristics. These special characteristics have been attributed to its plastic deformation manner based on non-dislocation mechanism. The authors previously studied on the behavior of strain-induced grain boundary migration (SIBM) in the Gum Metal that is a popular annealing process in most metallic materials containing medium density of dislocation, in comparison with that in a Ti-15V-3Cr-3Sn-3Al alloy, typical bate titanium alloy, and showed that SIBM tended to be suppressed in the Gum Metal compared with the Ti-15V-3Cr-3Sn-3Al alloy, and that migrating boundaries were pinned by some ellipsoidal particles in the Gum Metal, leaving some spherical particles inside the grain (off the boundary). In the present study, pinning force for a single particle with both morphologies has been assessed, using the obtained results of dimension and morphology parameter of the two types of particles. It has been theoretically confirmed that pinning force of the ellipsoidal particles is larger than that of spherical particles. This has been attributed to the fact that the observed dimension and the area theoretically in contact with the boundary at the same volume is larger in the ellipsoidal particles.

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High bendability as well as high strength and high electrical conductivity has been being demanded in copper alloys for the use of connectors where bending with small radius is performed, as electric and electronic components have been miniaturized. With this trend, speedy and quantitative assessment of bendability has also been being demanded. Although there have been several methods to assess the bendability of metal materials, none of them do not seem to have both speediness and quantitativeness. Two of the authors have recently proposed a new bendability-assessing method in aluminium alloys for autobody sheet based on the principle that the resistivity of the test piece increases because of the decrease in cross section area when cracking occurs during the bending deformation. The aim of the present study is to investigate the applicability of the new assessing method to a Corson series copper alloy that is currently used for connectors but still is required for further improvement in bendability. Test pieces of 0.23mm in thickness were prepared from the alloy sheet solution-treated at 800℃ for 1h and successively treated in three ways: i) water-quenched and subsequently aged at 480℃ for 3h, ii) water-quenched and iii) furnace cooled. Bending was carried out in two steps: firstly up to 90° using a pair of jigs for W-bending, and secondly up to 180°, both with inner radius of 0.0625mm. Resistivity was measured by means of four-terminal method at room temperature, before and after the W-bending and after the final bending. The obtained results showed that the resistivity increases in rough accordance with decreasing the bendability previously reported for the same specimen, and that the resistivity increase corresponds well to the occurrence of the crack on the tension surface as well as the expansion in thickness and reduction in length on the compression surface.

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A wheelchair with the function of lifting has performance of care lift's transfer and electric wheelchair's movement. This system is designed to assist a burden of nursing care, to transfer a severely disabled person who needs care to a wheelchair from a bed and to transfer him/her to a toilet seat from a wheelchair. This system is able to use not only home and institution but also outside location. This system has the possibility to board the car for the exclusive use of wheelchair because it becomes a compact size by folding mechanism. Additionally the system is able to run in the public road.

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A wearable leg support system based on manual control for people with lower limb paralysis has been proposed in this paper. We had developed a wearable leg support system, Manipuleg-1, that the wearer can control leg via a control lever attached at his or her shoulder. We have shown that the wearer can sit down and stand up from a chair using the leg support system by operating the control lever.

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In this paper, we propose a portable care lift. This lift uses no power of actuator's and it is designed to operate by man. This lift needs only one caretaker and supports to transfer a physically disabled from a wheelchair to a bed or the restroom. This lift is convenient, because it is usually equipped behind a wheelchair when folding it compactly. We can use this lift anywhere at indoor flat places such as home and institution. We verify the design's effectiveness through some experiments.

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We have developed a walking prosthetic devices for a person with mildly disabled lower limbs to go up/down steps and to utilize ordinary toilets. This device comprises two modules: a powered knee prosthetic device and a pair of telescopic crutches. We show the conceptual design of the walking prosthetic devices. In this paper we mainly discuss the telescopic crutch. This crutch has no actuator and its length is switched between two levels; it assists the person when standing up and sitting down in the short length state, while it maintains the body stability in a standing position when traveling in the long length state. We also show the results of the withstanding load of the crutches.

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For the severely disabled people who are paralyzed from the neck down, eye-control input device takes an important role as computer input support interface as other tongue, EEG and EMG based input method. The eye input device has an advance in more direct operation feel than EEG.EMG stepping cursor moving input method. On the other hand, eye input device is still costly compare with conventional input device. This study aims at developing a low-priced mouse control which constructs of the goggle and the USB-camera. This study consists of iris tracking performance part and mouse control algorithm part. Here, we adopted the adequate filtering and ellipse fitting for iris tracking. To cancel head motion, this paper proposes the relative displacement based mouse control methods.

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In the past, surrounding situation transmission technology that aims independent walking support for the visually handicapped person has been developed a lot but, technology that transmits surrounding situation of operator has not come to still solve the problem. This study is the developing the device that added function to support active communications by adding the function to transmit the position of the person in surroundings to visual agency walking assistance interface which has been developed in our study group.

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While convenience society advances, it becomes clear that psychological and physical stress gives bad influence to the human body by the factors such as over stressful competition or rapid change of living environment.This study conducts to develop the relaxation device that gives stress relaxation effect to subject while they are lying or asleep.This system considered on the adequate loading stimuli on foot bottom to induce relaxing effect.These representative signals are known as observed in wave sound. 1/f fluctuation is also observed in these phenomena. This study compared wave sound with 1/f fluctuation for investigates relaxation effect.

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The 1/f fluctuations are observed in many healing effects. However, it is still under consideration process as if the 1/f fluctuations induces healing. This study analyzes natural wave sound that is considered giving the healing effects, finds the existence of fluctuations similarity between time domain and frequency domain of natural sound. It proposes two types of method as the algorithm to replicate healing sound for the premise to generate pseudo natural sound as the vibro stimulation. One is the method to recomposite the maximum energy components of power spectrum. The other is the method to adopt fluctuations similarity between time domain and frequency domain.

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In Recent Japan, the Aging and falling birthrate is advancing. From those inuence, the manpower shortage and tax burden increase of the senior citizen welfare from aging people increase become important issue of concern. We need a little eect and simply physical strength measurement, because in a current physical strength measurement, not little eect input is given to the testee. Hence, this study describes physical capability assessment and proposals of the device and the index where physical strength presented by using gait motion for prevention accident of aging people. In this paper, I develope real time gait pattern analysis software to assess the walking performance of testsee. We propose gait assessment indices from walking cycle, up down displacement,and acceleration.

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This study constructs with 2 principal parts. The one is to propose an accelerated point tracking test to assess the mobility performance of human subjects not interfered from self compensative behavior against external load change and background factor. Another is to investigate the causal human mobility factor and fatigue factor of external factor as floor condition, material and other. This test shows the 3 tracking evaluation indices based on the marginal tracking performance and performance efficiency from an energy expenditure rate from EMG. The accelerated point tracking test on the several floor mats are investigated. The result showed mobility'performance mat shows 5-10% higher marginal tracking performance with lower energy expenditure rate than conventional mat.

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Sleep is indispensable to human acts. However, the sleep disturbance is one of the matters of social problem now. The topic concerning sleep came to be often taken up in media. And the attention of bedding has increased. Especially, the pillow attracts a lot of attention. In this study, we focus to the pillow and cervical vertebrae. It aims to examine the dynamic influence that pillow exerts on spine position. The experiment uses the photoelastic method.As a result, the stress in the cervical vertebrae has been understood to concentrate on the top part and the bottom part.

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Recently, the number of foot joint syndromes by an acquired transformation increases. Because loading condition and the structure of foot joint greatly influence them, the clarification of the mechanical property of foot joint is important. Especially, a flatfoot has a lot of patients as an acquired case. In this research, the bone in the arch of a normal foot and a flat foot was reproduced by three -dimensional model, the stress distribution was analyzed by the photoelastic investigation, and it made comparative study of them. The experiment analysis result showed the following things. The remarkable difference was seen by calcaneus. In ground plane, stress concentration caused the normal foot inside. Stress decreased as the normal foot went outside. On the whole, stress increased the flatfoot. And, reduction of the stress in an outside like a normal foot was not seen.

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The maglev technology offers long lifetime and better biocompatibility of the blood pump by eliminating the mechanical contact components from the device. We have developed a miniaturized maglev blood pump to support infants with cardiovascular disease. The pump consists of a self bearing motor and a levitated impeller. The impeller was suspended with self bearing motor in the axial direction. Target pump flow rate is 1 L/min against a head pressure of 100 mmHg. The length of the device and impeller diameter of the pump are 43.4 mm and 25 mm, respectively. The results of CFD analysis show that the developed pump produces target flow rate at a rotating number of 4,000 rpm. It is verified experimentally that the developed maglev motor has sufficient torque performance as an artificial heart for infant.

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We propose new treatment method with artificial heart aimed for recovery of heart function for the acute cardiac failure patients. We have developed the therapeutic artificial heart with the maglev technology which enables higher bypass flow. The pump consists of a levitated impeller and a self-bearing motor which has a magnetic bearing stator and the motor stator. The levitated impeller is set between the magnetic bearing stator and the motor stator. The magnetic bearing stator has four electromagnets, and the levitated impeller has a ring shaped permanent magnet and a yoke to enhance the magnetic power of the bearing. A centrifugal pump was designed based on the computational fluid dynamics analysis. A prototype of the pump was fabricated the actual pump performance was evaluated with a mock loop circuit. The result of experiments indicates sufficient pump performance of the designed centrifugal blood pump.

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Durability and hemocompatibility of MERA monopivot centrifugal pump A durability test and in vitro anti-thrombogenic tests were conducted for a MERA monopivot centrifugal pump made of polycarbonate newly developed for circulatory assist and open heart surgery. The 50 mm impeller is composed of 4 straight paths. A durability test has been conducted for 4 weeks at 300mmHg-4L/min with a closed circuit filled with 37'C saline. In vitro anti-thrombogenic tests were conducted at 200mmHg-4L/min with a closed circuit filled with 37'C bovine blood together with sodium citrate and calcium chloride to keep ACT at 200sfor two hours. As a result, the wear rate was 1.1 μm/day in average. The thrombus found in the female pivot was successfully removed by redesign. It was verified that the MERA monopivot centrifugal pump has sufficient durability and hemocompatibility.

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We have developed oxygenetor for pumpless Extracorporeal Membrane Oxygenation (ECMO) system. It is required low pressure drop, blood priming volume and gas exchange performance in pumpless ECMO. In this study, we performed analysis of oxygenetor using computational fluid dynamics (CFD) for increase in performance. In addition, oxygenetor was fabricated based on the result of CFD. In the CFD, it was calculated uniformity of flow velocity in fiber bundle, low blood pressure and low riming volume. O_2 was fully added to oxygenator, on the other hand, CO_2 removal was difficult in in vitro evaluation. The value of pressure drop was not constant was by nonuniformly of flow velocity. In conclusion, this result indicates that uniformity of flow velocity was depended on gas exchange performance and pressure drop.

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It is important to clarify the relationship between the hemolysis and degree/area of surface roughness under blood shear fields. From our previous study using a rotational shear stressor, we have obtained that the increasing hemolysis was related to the increasing shear stress due to the surface roughness. However we have not yet measured the increasing shear stress amount with the stressor. In this study, we tried to quantify the shear stress level using 6.8 times higher viscous test blood with dextran solution in order to detect the increasing shear stress effectively using a torque sensor of the stressor. As a result, hemolysis caused by surface roughness under shear flow field did not depend on the homogeneously increasing shear stress, but on fluid environment near the surface roughness.

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This paper reports the examination of the basic characteristics of an energy transmission system for an artificial heart when the energy system is placed away from the body. We measured the temperature of the primary coils of a transcutaneous transformer after changing the position of the transformer. Then, we assumed the power required to drive the artificial heart to be 10 W. Consequently, it was found the distance between the axes of the coils was less than 5 cm and the distance between the coils was less than 7 cm when a power of 10 W was supplied to the artificial heart at a temperature of less than 55℃. Therefore, the results of this study are considered useful.

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In this study, the analysis of stress distribution generated by the cornering force caused when turning to the automobile hub. The experiment uses the assumption parts of the same hub and the bearing and the load to the automobile hub has been increased by using the assumption parts of the bearing. The analysis methods are using the photoelastic method with FEM. It is clarify that the stress concentration becomes remarkable from the result by the cornering force the fillet R neighborhood in the boss root, the bolt hole, and beside contact department with the brake plate. Moreover, the FEM analysis lowers to concentration degree though the stress concentration tendency is almost corresponding in both analyses.

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The effect of coat strength on the dimensional accuracy of casting in expendable pattern casting (EPC) process was investigated experimentally. The aluminum alloy casting of the simple shape with the rib was cast by EPC process, and the dimensional change of the casting from the model was measured. When the sand was filled tightly, the dimensional accuracy and the appearance of the casting were good independently of the reduced pressure in the flask. When the sand was filled loosely, the positive different dimension of casting from the model was caused. Under the reduced pressure, this tendency was more remarkable and the leaching of the molten metal by the crack of the coat was observed. When the coat with high bending strength was used, even if the sand was filled loosely the different dimensions of the casting were small.

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The auto air conditioning systems for car ate composed of many sensor and actuator, and are complexly controlled such as the temperature and flow of ventilator, etc. As for the education to maintenance specialist of car in the university, it is necessary to make a simulator for understanding of the control methods to the auto air conditioning system. In this study, we make a prototype of the auto air conditioning system with controlling the system by die para-signal instead of the signal from sensor. The validity and the availability of system for teaching material are investigated in the report

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In the present paper, the erosion rate due to liquid droplet impingement has been evaluated in a small diameter range of tens of micrometers using the newly developed spray-jet apparatus. The erosion rate of aluminum material is tested with respect to the droplet parameters, such as the droplet velocity, the diameter and the number density, which are measured by optical imaging techniques. It is found that the non-dimensional erosion rate increases in proportional to the 5th power of droplet velocity, which agrees closely with that of previous study using large droplet diameters.

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The authors were able to successfully shape gears also with a cylindrical work-piece using the two-step shaping method. This research shaped gear by the method of allowing the plastic flow for outer of the radial direction of a work-piece material using a small outer diameter of work-piece. The specifications of spur gear examined were as follows: module 1.25, number of teeth 18. The outer diameter of work-piece is changed varied in order to examine effect of the reduction in cross-sectional area. Spur gear with complete teeth were shaped on almost all the shaping conditions examined, even when the reduction in area as low as 7% and punch pressure was relatively low.

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Structures of honeycomb sandwich made of aluminum alloy are light weight and high rigidity, and can be expected to improve fuel economy and environmental improvement. If possible, have the plastic machining in the honeycomb material of the plane can be expected expansion of the scope of application. In this experiment, cell size to double the size of sample using the three-point bending, guided bending and conventional size as compared to results, considering. Three-point bending results that conventional size than sharp local transformation has happened. The result guided bending of conventional than size core materials and surface material detachment and easy-to-be was admitted.

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In turning operations, it is effective to use a larger corner radius or a lower feed rate to obtain a good machined surface. However, turning at lower feed rates decreases productivity and it has a negative influence on the turning operation because of the continuous chip. In turning of a shaft having a step of specified corner R, it is important whether the corner radius of the turning insert is the same as specified corner R or lower than it. A turning tool with a large corner radius cannot adapt to cutting a shaft having a step of specified corner R. In this study, the surface roughness, cutting force, and tool wear were experimentally investigated in order to clarify the cutting performance of the turning insert having three-arcs-shaped finishing edge. Work piece material SKD11 was turned with two kinds of turning inserts that had different radii of the arc-shaped finishing edge.The main results obtained are as follows. (1) The machined surface of the insert having three-arcs-shaped finishing edge was better than that of the normal insert. (2) The wear progress of the insert having an arc-shaped finish edge was slightly slower than that of the normal insert. (3) The cutting force of the insert having an arc-shaped finish edge was almost the same as that of the normal insert.

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This is a research of the opening space of the reverse buckling type rupture disk. Determine what affect the opening space at the rupture disk by way of experiment. This time, the examined element is burst pressure, shaping pressure ratio, pressure rising time, disk thickness, burst temperature and primary side volume. The experiment is conducted with the burst examination device in three times at same condition. Result of experiment, It has been understood that burst pressure and shaping pressure ratio influence. It is thought that the influence of pressure rising time, burst temperature and primary side volume is small.

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In this paper, the effect of bond thickness upon the shear strength of epoxy adhesively bonded joints with dissimilar adherends is addressed. The bond thickness, t between the adherends is controlled to be ranged from 0.1 mm to 1.2 mm. Finite element analyses are also executed by ANSYS 11 code to investigate the stress distributions in adhesive layer of adhesive joints. The order of stress singularity is obtained from the analytical solution of Bogy's characteristics equation. As a result, shear strength of adhesive joint reduces with increasing bond thickness. Moreover, the failure of dissimilar adherends bonded shear joint has been initiated at a location with critical stress singularity order which is the interface corner of aluminium/adhesive. It is found that the shear strength prediction can be satisfactorily done by interface corner toughness, Hc parameter.

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In automobiles, suspension bush, a component of aluminum alloy/rubber joints, realizes high level of silence and comfortableness. Gravity-die-cast AC4CH alloys have been applied to this component, and are being expected to be replaced with pressure-die-cast ADC 12 alloy to reduce the cost. However, decohesion arising from the corrosion of ADC 12 at the joint has been reported. This corrosion has been attributable primarily to the high contents of harmful elements for corrosion such as Cu and Fe, and secondarily to the fine microstructure caused by the pressure-die-casting process. Besides, a new corrosion test that shortens the time for the test is required. In this study development of such test has been attempted by increasing the tensile stress applied to the joint. Many test pieces of joints of pressure-die-cast ADC12 and extruded A6N01 (reference material) with NR/BR rubber were attached to three types of jigs that can apply different tensile stresses on the joint, and were subjected to CCT, compound cycle corrosion test, in accordance to JIS K 5621. The results obtained in the CCT by 10 cycles showed that the effect of the tensile stress applied to the joint was smaller than the fluctuation in the corrosion resistance of the test pieces. The increase in the number of cycles might cause the effect of the tensile stress to be appreciable.

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The crack tip opening angle (CTOA) is a viable ductile fracture and could be used for elastic-plastic, crack propagation analysis without the constraint of LEFM. This paper reports on our investigation to correlate CTOA with the stress intensity factor, K, in stainless steel (SUS 316), single edged notch bend (SENB) specimens. The SENB specimens were cyclically loaded at various constant load amplitudes with a load ratio, R〜0.01. Fatigue crack extension rate of the specimens was measured by crack gage, during the fatigue crack extension. The fatigue data was then used to construct a K versus CTOA relation, similar to Paris' law of LEFM, in the presence of small to large crack tip deformation and net section yielding.

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In this research the temperature change of a metal foil according to the load stress was measured using infrared stress measurement method. Metal foil used three kinds (advance, aluminum, and copper). To measure these temperatures, test piece were made. This test piece to make a metallic foil pile to epoxy resin. As a result temperature change could be caught from 0.023[K] to 0.197[K]. The temperature change of all the foils was proportional to the load stress. Therefore the effect of thermo elasticity consists. In addition, stress distribution can be caught from the temperatures fluctuate distribution of the foil, and when an actual stress value is requested.

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The potential drop technique is widely used for the measurement of crack length in a compact-tension (CT) specimen. As the geometric shape of the specimen and the output leads distance have an influence on the relation between the value of potential drop and crack length, finite element analysis was made to derive approximation equation between them. The accuracy was shown to be satisfactory by comparing the calculations with the experimental results.

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Non-destructive evaluation of defect for ferromagnetic structural material SS400 was performed by magnetic flux leakage technique using a fluxgate sensor. Changes in magnetic flux densities could be measured around defect at a lift off height of 2mm, however, the size of the defect could not be evaluated. Especially at around adjacent defects which distance was 3mm, changes in magnetic flux densities of each defect were mixed and each defect could not be distinguished. In order to evaluate defect size quantitatively, inverse analyses of singular value decomposition were preformed. By eliminating smaller singular values properly, and by using the relationship between leakage magnetic flux densities and magnetic moment of defects, magnetic moment was calculated from the measured magnetic flux densities and the defect size was successfully reconstructed.

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A micro-flowmeter has been developed for high-speed and high-precision microfluidic device operations. Flow rate measurements on the blood flow in capillary vessel at fingertips were demonstrated using the prototype laser micro flowmeter. We fabricated the microfluidic devices with surface acoustic wave (SAW), and the microchannels using the ultrashort pulse laser machining system. The performance of controllability of the microfluidic device using SAW was investigated using the flowmeter.

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The phenomenon that the particle or the bubble is captured at nodes of standing wave by sound wave is widely known. Recently the phenomenon is theoretically clarified, and acoustic levitation technology is being established. If the acoustic levitation technology can be applied to the abrasive machining for control of the abrasive movement, an indispensable rotational and liner movement mechanism for the traditional abrasive machining become unnecessary, and the complicated machining in access, for example; the internal finishing of a tube, is able to be realized. In this study, we aim to proposal of a new method the abrasives with acoustic levitation, and develop a new polishing process that excludes machine movement mechanisms of driving. In this paper, the equation and condition of acoustic levitation is derived and acoustic levitation of a polystyrene foam is experimented.

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Dye-sensitized solar cell is a relatively newly developed low-cost solar cell. It is a photoelectrochemical system based on a semiconductor formed between a photo-sensitized anode and an electrolyte. Titanium dioxide, which is well known as one of the photocatalyst materials, is used as its semiconductor material in a form of nano-particles. In this study, it was investigated that the influence of surface micro-structures formed on transparent electrode, which is one of the constituent elements of a dye-sensitized solar cell, on the generating efficiency of dye-sensitized solar cell, because the increase in surface area of transparent electrode might bring an increase in light absorption. The surface micro-structures on the conductive transparent resin electrodes were fabricated by imprint lithography technique using fabricated mold with surface micro-structures. As a result, some improvement was observed in generating efficiency of developed solar cells.

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Today it is increasing the demand of the manufacturing speed, the product accuracy, and the cost of manufacturing, etc. in the parts of machines manufacturing. And the automation of the detection process is an indispensable technology. So this study aim to design and develop the automatic defect detection system on the machine parts list side by the image processing that used the wavelet transform.

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We report on an optical critical dimension and electric conductivity measurement technology for in-line inspection tool on metallization process of microelectronics. The idea of conductivity estimation from optical scattering, whole inspection system including the analyzing method, and demonstrations of critical dimension and conductivity measurements on silver and copper surfaces are presented.

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Synchronization of coupled system is a common phenomenon of nature. Its discovery dates back at least to the time of Christian Huygens, who remarked that two slightly out-of-step pendulum-like clocks become synchronized after they are attached to a same thin wooden board. In this study, two kinds of oscillation systems consisting of one opposite C type cantilever and another beam-shaped cantilever, with and without mechanical element to the support, have been proposed, respectively. The vibration modes, were simulated using a commercial Coventor Ware^<TM> software to guarantee the two resonant frequencies to mutually obey the relation of ω_1≒2ω_2, which are expected to be coupled through a coupling overhang. The synchronization of the fabricated oscillation systems will be further demonstrated and compared.

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Disk-type resonators employing in-plane resonant modes provide high quality factor in air at atmospheric pressure. In this paper, we have fabricated single crystal silicon (SCS) disk-type micromechanical resonators of 200-μm diameter with 150-nm-wide vertical transducer gaps. The gaps have been fabricated through a process including a single deep reactive ion etching (D-RIE) of SCS with a resist mask patterned by electron beam lithography. The resonant frequencies measured for the fabricated resonators agreed well with those predicted by finite element simulations. Furthermore, the D-RIE process conditions for the transducer gaps were improved. Using the improved D-RIE process conditions, less tapered gaps of 2μm deep were successfully fabricated.

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The present study aims to develop a method of forming a functional film for wire bonding by using dry laser plating. The paste containing 82 mass% Ag (100 nm in average diameter) was coated on a Cu lead-frame by a spin coater. After being sintered with an Nd:YAG laser (1064 nm in wavelength), the paste became a bulk structure with a thickness of 3 μm. When a ・25 ・m Au wire was bonded on the pad, average pull strength of 7.4 cN was obtained. This value is similar to that of an electroplated Ag film. However, excessive laser power promotes the diffusion of Cu to the Ag film, resulting in poor wire bondability.

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The novel method of filling complex micromold inserts for both positive and negative structures, i.e. high-aspect-ratio micropillar and deep microcavities are presented. Hollow microneedle array is the target prototype of such a complex replication. The mold features employed in this work are; an array of SU-8 pillars formed on a slope of silicon cavities and two-part insert of silicon cavity array aligned with comb structures. The cavities are fabricated using a combination technique of anisotropic wet etching and deep reactive ion etching. Megasonic agitation is applied during polymer casting into the mold inserts to resize the micro air-bubbles until disappeared.

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