Recently, the fuel cell vehicle which uses the hydrogen energy has been attracting attention because of environmental problems such as global warming and depletion of fossil fuel. With the spread of fuel cell vehicles, lower cost of each component is required. High-pressure hydrogen container for fuel cell vehicle is composed of a liner of 6000 series aluminum alloy and shell of carbon-fiber-reinforced plastic(CFRP). Higher strength aluminum is demanded in order to decrease the cost of the hydrogen container by reducing the amount of the expensive CFRP. Humid gas stress corrosion cracking test is one of the ways to examine the safety of aluminum alloys. However, the effect of the main alloying elements (Mg, Si, Cu) on the humid gas stress corrosion cracking behavior is not clear. In this study, using aluminum samples of various compositions, we investigated the effect of alloying elements on the humid gas stress corrosion cracking behavior in 6000 series aluminum alloys.

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Now, global warming and depletion of fossil fuels is seen as problems. A vehicle powered by fuel cells get a lot of attention. A vehicle powered by fuel cells uses hydrogen for fuel. Now, a vehicle powered by fuel cells mounts high-pressure hydrogen container. This container is covered with carbon-fiber-reinforced plastic (CFRP) on outside and a liner of 6000 series aluminum alloy on inside. A reduction of carbon-fiber-reinforced plastic (CFRP) is necessary, because carbon-fiber-reinforced plastic (CFRP) is very expensive. More strong a liner of 6000 series aluminum alloy is considered for one of the method of reduction. Humid gas stress corrosion cracking test is good for selection method of candidate material of high-pressure hydrogen container. But, evaluation of humid gas stress corrosion cracking is difficult. In this study, I evaluate humid gas stress corrosion cracking test on aluminum alloys for high-pressure hydrogen container.

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In this research, composite planting has studied using the improved trivalent chromium bath. It is known that various kinds of particles can be introduced into the chromium layers from trivalent chromium baths, though composite plating is generally difficult by the hexavalent plating bath. So, particles of hexagonal boron nitride or zirconium oxide were added and dispersed into the improved trivalent chromium bath and composite layers were electrodeposited．It was found that the hexagonal boron nitride particles were not composited. However, zirconium oxide particles could be successfully composited. The properties of the composite layers obtained were examined and the number of cracks in the layers decreased than that of the non-composite ones.

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High entropy alloys (HEAs) are defined as the alloys with five or more elements with atomic concentration between 5 and 35%. It has been reported that many of HEAs have superior properties, such as high strength, high temperature strength, and good corrosion resistance. However, it is difficult to fabricate HEAs with conventional manufacturing routes, including forging and rolling. Therefore, we experimented in applying electron beam melting (EBM) which is known as a 3D printer for metallic materials to the fabrication of HEAs. We succeeded in producing equiatomic AlCoCrFeNi HEAs by EBM and investigated the microstructure and mechanical properties. As a result, plastic deformability of EBM specimen was much higher than that of the conventional casting specimen due to the constituting fine grains and the formation of ductile secondary phase. On the other hand, it was confirmed that Vickers hardness was varied depending on the product’s build height in EBM process.

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In recent years, the demand of energy is growing and lots of energy are consumed. As a solution of the problems such as global warming, the drain of fossil fuel, etc, effective using of the hydrogen energy and fusion nuclear are expected. In this study, a basic research to elucidate the relationship between hydrogen embrittlement and irradiation damage is carried out. Two materials of an austenitic stainless steel and an aluminum have has been irradiated up to 1[dpa] by Cu²⁺ ions. After a cathodic electrolytic charging, HMPT and TDS are investigated about above materials. As the results, the release of hydrogen from grain boundary was confirmed and the quantity of released hydrogen increased by the irradiation damage.

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Stainless steels are currently used as structural materials for cars, trains, and other various engineering productions. To further improve performance of such products, stainless steels with higher strength and smaller weight are required. In this research, cold rolled stainless steel SUS301 specimens, which have very high tensile strength near 2 GPa, were subjected to SSRT (Slow Strain Rate Technique) tests and effects of test environment on mechanical characteristics were investigated. Effect of test environment on the fracture behavior was also studied using SEM (Scanning Electron Microscope).

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Traditional machining of permanent magnets is difficult because of magnetic forces and the brittleness of the materials. However, electrical discharge machining (EDM), a non-contact thermal machining method, has been successfully applied for the shape machining of magnetic materials. In this study, to clarify the relative degrees of influence of the change in shape and internal temperature in the machining of a bottomed hole in a square magnet, electro chemical machining (ECM) has also been applied to machine a bottomed hole with the same dimensions as that used in EDM. Because the internal temperature does not rise in ECM, only the influence of the shape change should appear in the magnetic pattern. The ECM equipment and machining results are presented herein. The machining results by ECM are compared with those by EDM, thereby allowing to individually study the influence of shape change and internal temperature..

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A new operating lever with bilateral control for the leg support system，Manipuleg-2，for people with lower paralysis is presented in this paper．We had developed a wearable leg support system，Manipuleg-2，that the wearer can control leg via a control lever I attached at his or her shoulder．The conventional control lever for our wearable leg support system has been based on unilateral master slave control，so that the wearer cannot feel the leg motion．The newly developed control lever is using the bilateral control，and the lever is able to sense the motion of leg via his or her hand．

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This paper describes the standing stabilization for people with a disability in lower limbs wearing an exoskeletal robot. There is a problem that people with a disability in lower limbs do not have sense of sole which is important for maintaining standing posture. Zero moment point or center of gravity are presented to the subject using visual and tactile method. As for tactile method, experiments are conducted for various skin part and various distance of adjacent solenoid pins of the tactile device.

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It is one of the significant problems for hospital patients to transfer from the bed to a wheelchair. This study focused on the transfer motion from the bed and developed assist system of transfer motion for the bed user, without lifting motion performed by the caregivers. Thin skin career sheet was inserted below the patient sitting on the bed side, and it was hanged on the cantilever chair equipped on the omnidirectional wheelchair. We propose a method to decrease the friction caused in the inserting the career sheet by changing the patients posture.

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In this study, knee joint torque generated by sports spats in running was estimated by numerical simulation. The fabric materials for sports spats show anisotropic stress strain relations and stress softening in mechanical properties. Therefore, an anisotropic hyperelastic model was applied to numerical simulation. Uniaxial monotonic tensile tests and uniaxial cyclic tensile tests were carried out to estimate material parameters of an anisotropic hyperelastic model. Then, we supposed that the strain of sports spats on human body during running was reproduced using 3-dimensional computer graphic model. As a result, stress and strain distribution were calculated, and knee joint torque produced by sports spats during running was calculated. From the numerical result, joint torque caused by sports spats depended on bending angle of knee.

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In this study, Effect of string diameter on the hitting surface for tennis rackets were evaluated. The newly designed aluminum jigs were developed which were able to evaluate only the mechanical properties of the hitting surface. Two experiments were conducted to evaluate effect of string diameter on the hitting surface. One was tensile test for the string used for tennis. As a result, three kinds of strings did not have the difined difference in the rerlationship between strain and stress. The other is loading test of the hitting surface. As a result, increasing the diameter of the string showed the same effect as increasing the tension of string.

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For the healthy life of the elderly, the health of their teeth is regarded as one of the most significant factor. But it is very difficult to learn the right brushing way, because no one can see the teeth and brush while brushing. The object of this research is to develop a tooth brushing simulator that enables to view the teeth and brush, and to feel the response of the toothbrush for obtaining the right brushing technique. In this paper, as the first step of development of the tooth brushing simulator, a simple simulator with a single hair brush was demonstrated.

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This paper describes an intuitive interface to operate the computer based on upper limb motions. The skeleton information in humans of the Kinect sensor was used for detection of joint positions of upper half of body. From the obtained information, the motion of the operator was recognized to reflect a mouse operation. Here, we constructed the system which could choose two displays, scroll and move the position of the cursor by changing the functions according to the length of the extended right hand, and click with the left hand. In addition, we made the wearable device on the wrist for sensory feedback to user. The operability of the developed system was examined by the trial experiments.

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This paper suggests a new method of recognizing a facial orientation based on tracking a pair of nostrils. Due to the fact that nostril shape is stable compared with other facial parts such as eyes or mouth, the nostril image was treated as a feature point and it was taken in real-time for image processing via an USB camera. When a man faced to up and downward, the darkness areas of both nostrils were increased and decreased, respectively. On the other hand, the difference between both nostril areas could be caused in cases where the face was turn to the left or right directions. The obtained characteristics were utilized for recognition of a facial orientation.

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This paper describes the human face detection based on special feature color. Here, the skin color was picked up as a special feature. The human’s face was observed by the USB camera in real time. First of all, human face images were obtained under the various brightness environments. As a results, it was found that red component of the facial skin is stronger than any other facial parts such as eye, nostril or mouth. In our proposed system, the original image was changed into the rough color image and the smoothing procedure was applied to calculate the weight value of the skin color and eliminate noise. In cases where the head was tilted or the face was turned to the side, it is difficult for the existed method to detect the face, because it was adjusted for the frontal face. On the other hand, our proposed system could detect the tilted face and side face.

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In the conventional motors, the shaft is supported by contact type mechanical bearings. However, there are some problems like a friction loss and generations of dust, vibrations and noises. To overcome these problems, an active magnetic bearing is applied such as the vacuums, extremely low temperatures, and clean environments because of the non-contact levitation control capability by using an electromagnet. The requirement of 5-axis active control for the stable levitation and rotation result in the large size system. Then a self-bearing motor has been proposed to realize the downsizing and high-speed rotation of the system. In this paper, a permanent magnet reluctance (PR) type self-bearing motor is proposed. The rotor of the motor consists of magnetically salient poles with interior permanent magnets for the use of the flux barriers. Then, the motor is applicable for a wide range of variable-speed operation while maintaining low induced voltage. The fundamental characteristics of three types of the analysis models are analyzed and the results are reported.

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A maglev blood pump has been developed to recovery cardiac function of acute heart failure patients. A rotating speed of the levitated impeller of the blood pump is changed synchronizing with heart beat to increase coronary flow of a natural heart and reduce load of the natural heart. Fluid force in the pump causes displacement of the impeller in the radial direction which non-controlled axes. The fluid forces of the impeller are analyzed with setting the impeller model at the position are during pulsatile operation. The fluid force is increased with increasing the radial displacement of the impeller. The maximum fluid force is 0.92 N when the distance between the center of the impeller and the pump is long.

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Thrombus formation in blood pumps is a major problem. It has been reported that the shear rate is closely related to thrombus formation in blood pumps. However, the mechanism of blood coagulation in a shear flow field is not yet fully understood. The purpose of this study is to evaluate the effect of shear loading on the reaction of blood coagulation factors quantitatively. Human blood and porcine blood were used as test blood and loaded shear using a rheometer. After shear loading to the test blood, the activated partial thromboplastin time (APTT), prothrombin time (PT), and reaction time of blood coagulation factors were measured. Results showed that shear loading prolonged the APTT and PT of human blood. Accordingly, the reaction time of human blood coagulation factor V was prolonged. The reaction time of porcine blood coagulation factors after shear loading differed from that of human blood coagulation factors.

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A centrifugal blood pump is used as an extracorporeal circulation pump for severe heart failure patients. An impeller in the centrifugal pump rotates to send blood into the body. When rotates with high rotational speed, hemolysis is occurred, while when rotates with low speed, thrombus formation is generated. However, it is not clear the quantitative relationship between shear stress and hemolysis or thrombosis. Especially, surface roughness on the blood contacting surface increases the amount of hemolysis under shear flow. This paper describes how much degree of shear rate as an indicator of shear stress cause the amount of hemolysis on the roughened surface, and cause reaction time and the amount of thrombus using a rheometer. As results, we obtained that increasing shear rate under 4,320 s^-1 enhanced the amount of hemolysis due to the Ra of surface roughness and inhibited the thrombus formation quantitatively.

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Zeolite/HA composite porous medium was prepared by the Gelation Freezing Method. Montmorillonite was used as a bonding material. Composite porous medium was prepared by freeze-drying a slurry which was added to aqueous gelatin solution to powder mixture of zeolite, HA and montmorillonite. Prepared the complex was heated at 500 ℃ and 800 ℃. The crystallinity was evaluated using X-ray diffractometer (XRD). The surface was observed with a scanning electron microscope (SEM). Flexural strength was calculated by destructive testing. In SEM analysis, it was observed that there is a pore in the all samples. The lower freezing temperature, the smaller pore size becomes.

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Vascular smooth muscle cells (SMCs) actively remodel arterial wall in which they are exposed to mechanical signals. We recently demonstrated that, in SMCs cultured on a flat normal substrate, actin cytoskeleton has a mechanical connection with the cell nucleus and their internal mechanical signals are transmitted directly to the nucleus. This intracellular force transmission mechanism is important for understanding smooth muscle pathophysiology in diseases such as hypertension and atherosclerosis. However mechanical environments around SMCs in vivo are quite different from those of the cultured cells: they show elongated shape and form a tissue aligned in the circumferential direction of the arterial walls, and they exposed to cyclic tensile stress as a result of the pulse pressure. Thus in this study, we developed cell culture systems based on the mechanical environment of blood vessels: we developed the micro-grooved collagen substrate to induce the elongation and alignment of SMCs like in vivo, and developed a cyclic stretching system for applying the mechanical stimulation. By using this system, we found that morphology of actin cytoskeleton and the nucleus were quite different between the cells cultured on the flat normal substrate and the micro-grooved collagen substrate.

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Ultraviolet (UV) radiation exerts adverse effects on genome stability, alters the normal state of life, and causes many kinds of diseases by inducing DNA damage. In this study, we investigated the effects of cyclic stretching mechanical stimulation on the nuclear morphology and UV radiation resistance of DNA in epithelial-like cells derived from Xenopus laevis (XTC-YF). We found that the intracellular actin cytoskeleton and the nucleus became elongated and aligned with the direction of zero normal strain (~62° with respect to the stretch direction) following the cyclic stretch exposure. The UV radiation-induced DNA damage, estimated by the fluorescent intensity of the phospho-histone γ-H2AX, was significantly inhibited following the cyclic stretch exposure. These results indicate that cyclic stretch-induced morphological changes of the nucleus possibly improve the UV radiation resistance in XTC-YF cells.

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We have developed the integrated low-level energy adhesion technique (ILEAT). Heat and pressure are used as the integrated low-level energy. ILEAT can make soft living tissues adhered to each other minimally invasively. In order to reveal the adhesion mechanism, living tissues structural changes by heat and pressure were investigated. The tissue adhered by a heat of 100℃ and a pressure of 1.25 MPa was observed with FIB-SEM. The heated only tissue, the pressed only tissue and the non-treated tissue were also observed. SEM images were converted into binary images and the quantitative data of each tissue structure were obtained. The adhered tissue indicates denser structure than other samples.

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We propose a noncontact defibrillator using magnetic stimulation by a figure-eight coil, which consists of two coplanar coils. In order to stimulate the heart completely, a uniform distribution of the electric field in the heart is required. In this paper, the behavior of the distribution of the electric field in the thorax was analyzed when changes were made to the distance between the two coils, frequency, and outer radius of the coils. It was found that selecting a distance of 30 mm between the coils, a frequency of 1 MHz, and an outer radius of 75 mm achieved an equable distribution of the electric field in the heart. However, taking the SAR (specific absorption rate) into consideration, we note that a frequency under 500 kHz is preferable, because the value of the SAR at 1 MHz exceeds the general public and occupational exposure limit specified in ICNIRP (International Commission on Non-Ionizing Radiation Protection) guidelines.

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We attached strain gauges to three places of the right hand thumbnail. We measured thumbnail strain when striking sponge with a cylinder. We changed diameter of the cylinders. We changed the weight of the cylinders. Thumbnail strain when striking is compared with measured points and differences in diameter, difference in weight.

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We created the three-dimensional upper arm model and simulated the motion of shoulder abduction using this model. We used CT photography for creating the bone models. The muscle models combined the contractile and elastic elements. The ligament models were defined as springdamper model. We evaluated the accuracy of this model by comparing simulation results with measured datum. As a result， this model could simulate the shoulder abduction angle of no less than 30° without considering the motions of scapula and clavicle.

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A three-cluster type mobile robot for ascending and descending stairs is proposed in this papaer. Two-wheeled cluster balancing mobile robots are developed extensively,however they cannot traverse stairs. We have proposed a stabilizing control method for the three-wheel cluster type robot,and shown the effectiveness of the method by simulations.

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In this paper, a wire driven one-legged hopping robot with hip, knee and ankle joints has been developed and the method of stable jumping has been proposed. This robot has a characteristic that each joint of the leg is wire-driven by a motor mounted on the body. In order to achieve a stable jumping, we adopted the virtual leg with the pivot at COG of the robot. In stead of controlling the angle of each joint we control the length and the swing angle of the virtual leg, and the angle of ankle joint. The control law is decomposed into a jumping control law and a posture control law. The length of the virtual leg is controlled the jumping control law, while the swing angle and ankle joint are controlled the posture control law.

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This paper tries to decompose the vector space of muscle contraction forces of robot arms driven by biarticular antagonist muscles into the direct sum of its subspaces. To this end, we define two linear maps: one maps muscle contraction forces to joint torques while the another maps muscle contraction forces to joint stiffness. Then we can prove that the kernel and the image of these maps decompose the muscle contraction force space into the following three subspaces: subspace of contraction forces that contribute motion of the robot arm, subspace that determine joint stiffness, and subspace that have no effect on neither motion nor stiffness.

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This paper deals with the vibration control of buildings with remote seismic data. The active vibration control is known as the vibration control method that achieves the best control performance compared to other vibration control strategies. Mostly, the active vibration control has been realized by as the feedback control only. The feedback control law is obtained based on linear and/or nonlinear control. In this paper, the feedforward control based on the preview control methodology is applied to the active vibration control. The preview data are generated with the artificial neural network that is driven with the seismic data that has already been obtained in the place of the building to be controlled and the remote observatory. With the remote seismic data, the preview control is possible by using the estimated future earthquake disturbance data in the place of the building. Simulation studies shows the advantage of the present approach.

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A networked control system has been developed to realize the distributed all-round active damping system which can be applied for various relatively small-size equipments with add-on style when vibration problems have occurred. This paper describes about development for the networked controller system which is the distributed controller using real-time network (RTN) technology and enable following features: fast response, compact and scalability of I/O number. The result of the experiment using our actual system which consists of 8 input / 8 output is also described. As a result, the response performance was 29.2 us and it was indicated that our system could be applied to the distributed all-round active damping system.

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The flange climb derailment of railway vehicle is caused by the phenomenon that the wheels climb up the rail when the lateral force gets excessive. In particular, the turnout has a structure that the flange climb derailment is likely to occur compared with the general track. In this paper, the running safety of turnout sections is analyzed using the multi-body dynamics analysis tool. As the results, it is showed that the first wheelset on the turnout of trailing direction should be especially noted in terms of the value of the wheel rise. It is also confirmed that the larger the friction coefficient is, the larger the value of the wheel rise.

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The alignment irregularity of the track has major impact on the quality of passenger’s comfort and the running safety. Especially, the alignment irregularity directly affects the value of the derailment coefficient when the vehicle running on a sharp curve. The irregularity is normally measured by a track inspection car. Therefore, the measurement frequency is limited due to the cost of the measurement. In this paper, the alignment irregularity is estimated by using accelerometers attached to the axle-box. Using a multi-body dynamics analysis tool SIMPACK, the fundamental effectiveness of proposed estimation on curved section is mentioned.

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The vibration-assisted cutting was performed to fabricate surface textures composed of numerous periodical concavo-convex patterns at Sub-μm scale anticipating future usage as the micro/nanotexture mold for injection molding. In the experiment, a modeling wax workpice was machined using a sharply pointed triangular diamond indenter tip vibrated by a piezo actuator in the direction of the cutting depth with μm order amplitude. As a result, a textured surface composed of numerous inverted triangular pyramidal impressions surrounded by pileups are successfully fabricated, and their average dimensions are about 60 nm in height and 580 nm and 900 nm in pitches in cutting and feed directions, respectively.

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DNA damage induced by the radiation including ultraviolet (UV) light exerts adverse effects on genome stability, alters the normal state of life, and causes many kinds of diseases. Hear we investigated the effects of the nuclear deformation on UV radiation resistance of DNA in epithelial-like cells derived from Xenopus laevis (XTC-YF). XTC-YF cells spread normally in the space between micropillars whose center to center spacing were 9 μm and their nuclei appeared to be “trapped” mechanically on the array of pillars. The average fluorescent intensity of DNA was significantly higher in the cells cultured between the pillars than that on the normal flat substrates. We found that the UV radiation-induced DNA damage, estimated by the fluorescent intensity of the phospho-histone γ-H2AX, was significantly inhibited in the cells cultured on the pillar substrates. These results indicate that the inhibition of UV radiation-induced DNA damages might be resulted from DNA aggregation caused by the mechanical stress of the nucleus of the cells on the pillars. Our study first demonstrated the nuclear stress-induced inhibition of DNA damages in living cells.

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In this paper, we propose a new method for geometrically simulating a surface ground by the rotary grinding machine. In our method, a grinding operation with a single particle is considered as a milling operation with a very thin ball-end cutter. Geometric milling simulation technology is thus applied to visualize the ground surface realized by many grinding particles. In order to accelerate the computation, the depth buffer mechanism of GPU is used. An experimental simulation system is implemented and its performance is demonstrated. The system can visualize the ground surface with more than 2500 particles in 10 seconds.

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In our previous study, it was found that the wear life of the DLC/AlN hybrid film compared with a DLC film deposited directly onto Al-alloy could be improved by controlling the hardness of the AlN intermediate layer film．However, the hard coating like above films has a possibility to decline the fatigue strength of based material. In the present study, to ensure the fatigue reliability of Al alloy coated with DLC/AlN hardness gradient hybrid film, the fatigue strength and the fatigue failure mechanism were investigated. Fatigue strength of A7075 alloy coated with DLC/AlN hybrid film in lower stress side was higher than the untreated material, but that in higher stress side was almost the same as the untreated material.

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In this paper, a diamond tool is used in the ultra-precision machine. With using a diamond tool in the ultra-precision cutting, the surface roughness can be within 10nm..This paper performes the mirror-like cutting of the aluminum substrate and basic experiments such as the adjustment of the work piece center coordinates. It also disucusses the principle of cutting and the result.

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The 3D printed object is suffering by the layer grooves. We developed the 3D Chemical Melting Finishing (3D-CMF). It can remove the layer grooves effectively and 3D-CMF is able to improve mechanical strength of the 3D printed structure. However there is no suitable process for the complex shape of the 3D printed structure. Therefore we developed the mechanism of the 3D-CMF that can adjust the amount of the processing. In this paper, we developed the automation mechanism of the 3D-CMF that is suitable for the complex shape of the 3D printed structure.

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Electrical Discharge Machining is a process to remove a portion of material by electric discharge in insulating working fluid. The material is melting by discharge and blown off the material by the vaporizing explosion of working fluid. The melting section is conceivable to be blown by the vaporizing explosion. Expanding and contracting of the bubble are affected material removal. The vaporizing explosion power is determined by the input energy, the removal quantity of material is determined by the degree of vaporizing explosion power. By the way, Micro-bubble is a bubble of 50 μm or less in diameter. Micro-bubble has special nature that increasing in interior gas pressure, increasing in ion concentration around the gas-water interface etc. We consider change the characteristics of electrical discharge machining by micro-bubble mixed fluid. The vaporizing explosion is considered to be weakened by micro-bubble mixed fluid and the surface roughness seems to be improved. So we do electrical discharge machining using pure water and micro-bubble mixed fluid and researched characteristics of electrical discharge machining.

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There is ELID grinding method as a processing method using a fine abrasive grindstone. There is a high-efficiency machining method that allows the dressing of the machining and grinding wheel at the same time by applying electrical energy to the grindstone during processing. We contained the carbon dioxide coolant into the grinding fluid in order to improve the surface modification effect.As a result, rubber bonded wheel of no lubrication, it maintain high removal amount improves the dressing effect of the grindstone. Rubber bonded wheel of lubrication, it does not obtained the amount of removal.

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Among the types of finishing ELID grinding wheels, there is metal-resin bonded wheel containing resin balls. We have developed a resin ball wheel to investigate the effect of the surface roughness due to the difference in the bonding material. In this paper, we conducted tests to determine the initial electrolytic dressing characteristics, Result from the electrolytic dressing characteristics experiment shows that by performing electrolysis, the electrical resistance of the grinding wheel surface increased.

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In recent years, competition in the manufacturing industry is growing increasingly intense every year on a global-scale. For this reason, higher performance and miniaturization of products, weight reduction are important challenges to companies. The same demands are also made to tools essential to manufacturing such as grinding wheels. To meet these demands, the authors are developing a system which combines 3D printing and PELID to build grinding wheels, ELID for improving the wheel surface to provide the required grinding wheel performance, PELID (Patterning with Electrostatically Injected Droplet) which is a liquid ejection technique for controlling the distribution of abrasives in the grinding wheel. This report discusses the results of reviewing the system for fabricating grinding wheels.

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According to recent trends, nonspherical shape optical elements is more required by optical instrument is going miniaturization and high-precision. Nonspherical shape optical elements is made by die. So, die is required high-precision. It requires grinding by fine grain whetstone. This experiment purpose making fixed abrasive by fine grain whetstone. This has subject that fine grain whetstone is condensing. The subject can clear by method of PELID. But, this way has new subject. It is repulsion. The method of PELID is using electricity for spraying fine grain whetstone. And it has electricity. It hinder spraying next fine grain whetstone. So, I propose spraying with changing electricity direction. By this way can be laminating fine grain whetstone and making fixed abrasive.

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Profile shape evaluation by detecting tangential angles of the profile can evaluate profiles accurately without any shape references and it has been adopted for evaluating highly accurate objects from ancient. It makes the method to be also competent for evaluating large objects. Here, we use a gyro for detecting the angles. It can evaluate profiles in a horizontal plane, which cannot be evaluated by an inclinometer. It can also evaluate profiles without being limited in its measurement range, while that of an autocollimator is limited by its measurement beam range. Fluctuations of angular signal of the gyro are eliminated by continuous reversal measurement, which is carried out by obtaining second differences of the angular signals from the continuously rotating gyro. The angle of the gyro rotating axis against the axis of the earth rotation can be derived by using two gyros rotating inversely with each other without being affected by the fluctuations.

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Computer simulations are generally used to find any potential problems prior to the actual manufacturing process of workpieces. Most of the workpiece shape is in a Z-map representation, which requires a large amount of data to accurately record a high resolution model. To solve this problem, we propose an irreversible compression algorithm for Z-map models using two-dimensional wavelet transform with a specified maximum error. The input shape data is transformed by using 2D wavelet, and the maximum errors caused by virtual pruning of highfrequency components are recorded simultaneously. Nodes in the wavelet tree are pruned if the absolute value of its error by the virtual truncation is within a tolerance value specified by the user, and the remaining tree nodes are compressed reversibly using gzip compression library.

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This paper presents an investigation of the thermoelectric performance of super lattice structure diamond-like carbon (DLC) Films deposited on glass substrates using unbalanced magnetron sputtering (UBMS). It was measured Seebeck coefficient and resistivity of the DLC film. Then, to evaluate its thermoelectric performance. The super lattice structure DLC films showed a Seebeck effect, and they had p-type semiconductor characteristic. The super lattice structure DLC than a W doped DLC single layer film is the Seebeck coefficient is increased. The superlattice structure DLC than a W doped DLC single layer film is the specific resistance is increased. Power factor (PF) of the superlattice of the DLC film was lower than the W doped DLC single layer. Results show that the PF quality of superlattice structure DLC films was affected strongly by the magnitude of the specific resistance.

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The static and fatigue behaviors of discontinuous carbon fiber-reinforced polyamide (DCF/PA) composite have been examined. Static tension and compression tests are first performed at different temperatures (RT, 70°C and 130°C) to quantify the temperature dependence of basic mechanical properties of the composite. Then, constant amplitude fatigue tests are carried out for different stress ratios (0.1, χ, -1, and 10) at different temperatures (RT, 70°C and 130°C), respectively. The fatigue test results demonstrate that the S-N relationship of the discontinuous fiber composite significantly depends on stress ratio, and the fatigue degradation occurs most rapidly at the critical stress ratio in line with the observations made thus far for continuous fiber composites. Finally, the anisomorphic constant fatigue life diagram approach developed for continuous carbon fiber composites is applied to the DCF/PA composite, and it is proved that this method can successfully be used to predict the fatigue life of the discontinuous carbon fiber composite at different stress ratios.

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Development of an engineering method for predicting the ratcheting in an engineering thermoplastic polyamide 6 has been attempted. For this purpose, the ratcheting behavior of polyamide 6 is studied with emphasis on its temperature dependence. First, mechanical ratcheting tests with different levels of maximum stresses are performed on coupon specimens at different temperatures, respectively. The experimental results show that the accumulation of ratcheting strain in the polyamide 6 is significantly dependent on temperature as well as the maximum level of stress cycles. The ratcheting behavior is similar to the transient creep behavior in all aspects of its stress and time dependence. It is demonstrated that a master curve can be identified for the ratcheting data obtained over a range of temperature by scaling the time axis with the help of a shift factor that depends on stress.

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