In this research, two anodized aluminum plates were bonded with unsaturated polyester resin, and the influence of the anodizing conditions on bonding strength was investigated. For this purpose, aluminum was anodized on two conditions in 4mass% oxalic acidic solution. Conditions 1, voltage was fixed by DC25V, solution temperature was changed from 20℃ to 70℃, and maximum anodization time was 10.8ks. Conditions 2, solution temperature and anodization time were fixed in 40℃ and 3.6ks, respectively, and voltage was changed from DC 3V to 45V. In result, in order to enlarge the bonding strength, it was important to enlarge the surface porosity of a film, and for this, it is thought that high solution temperature, long anodization time, and low voltage anodization were effective.

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Tissue engineering is a promising alternative for treating bone defects. In order to precisely match the irregular boundaries of bone defects as well as facilitate clinical application, scaffold design should be improved. In this study, the scaffold was fabricated by a salt leaching-phase inverse technique of shape memory Polyurethane (SMPU). Different sizes of salts were evaluated in order to obtain scaffolds of different pore sizes. Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray micro-computed tomography (μ-CT) demonstrated that the three-dimensional porous polyurethane scaffolds were obtained. Mechanical properties and biocompatibility of scaffolds were analyzed by Compression Test Machine (KES-FB3), thermal mechanical analyzer (TMA) and cell experiment with Osteosarcoma MG-63 cells. Thus, this scaffold represents a potential application prospect in the field of bone tissue engineering.

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The purpose of this study is to consider the optical properties of thin film materials by the spectral characteristics of optimized multi-layer thin film structure. When designing a multi-layer film, it is essential to consider the optical properties of thin film materials, such as wavelength dispersion of refractive index and absorption. We propose a method to design a multi-layer thin film structure composed of the substructure with high reflectivity for a certain wavelength using a genetic algorithm. The effect of the optical properties of materials to the spectrum is examined based on the results obtained by design optimization.

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The purpose of this study is to generate the gait of a two-legged robot. Stepping points are determined optimally under the conditions of maximizing walking speed and minimizing energy for walking. The gait generation problem is reduced to a combinatorial optimization problem solved by using genetic algorithm. Orbits of toes and hip between stepping points are generated by means of parametric modeling. In the previous research the transition behavior of the walking speed which changes from acceleration to constant speed and from constant speed to deceleration is generated by using optimization method. In this paper, we report the results of a multi-objective optimization that takes into account the target speed of transition pattern and energy consumption minimization.

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For residential windows, transparency and lighting properties are required at the same time. It is also necessary to have thermal barrier ability. To achieve both transparency and thermal barrier effect, it is necessary to control independently the transmission of visible light and near-infrared light spectrum. If the curtain having such a light control function by loading the window of the housing, windows can achieve high functionality at low cost. In this study, optimum design of a multilayer film structure that can transmit visible light and shield against heat.

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Light can be controlled by using sub-wavelength periodic structures. Subwavelength periodic structure is the structure as small as the wavelength of light. This technology is based on the optical phenomena in the nano-structures. There are variety of optical functions depending on controlling wavelength and structure. Maltipropose design techniques are desired, which can be designed the sub-wavelength periodic structures in consideration of various design specifications. We propose a design system to obtain the design value of the sub-wavelength periodic structure to realize the design specifications.

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Structural color comes out of scattering and interference on specific wavelength light by microstructure, it's differ from pigments. If structural color can visualized, it lead to solution of relation between structure and color. In structural color, the color generally evaluated by reflection spectrum. But it's difficult that understand or confirm a color intuition only a graph of reflection spectrum. In this study, structural color is visualized in CIE color system and HSV color system. Reflection spectrums of a male adult Red-flanked bluetail's feather that calculated by finite element method (FEM) are indicated by the two color systems. If absorption is not present, a result color was bluish color. If absorption is present, a result was greenish color. These results agree with a shape of reflection spectrum.

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This work describes transient heat transfer characteristics from a horizontal heated cylinder at a uniform temperature, placed in a cylindrical container filled with cold water. The scaling analysis has demonstrated three different heat transfer regimes as the heat process advances with time. The times that differentiate the three regimes have been identified and derived as a function of the Rayleigh number and the geometric aspect ratio between the inner cylinder and the cylindrical container diameters. The numerical experiment has been performed in order to prove the correctness of the scaling analysis. It is shown that the results derived by the scaling analysis agree well with those from the numerical experiments.

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The flow of the viscous fluid which circles between the rotating cylinders is maintaind to be balanced by pressure, gravity and the surface tension on the fluid surface. However, the wave phenomenon is occurred on the free surface when the Reynolds number is increased. The Taylor vortex flow in an asymmentric system is a Couette flow state when the Reynolds number is smaller than a critical Reynolds number. Then, the flow is demonstrated to move to the inner wall of the outer cylinder by the action of the centrifugal force with the increment of the Reynolds number. Moreover, the surface flow develops to the complicated wave phenomena. So far, the instability and the development of this surface flow with the Reynolds number has not been clarified. This resaearch is to clarify the development of the surface flow of the fluid circulating between the cylinders with the Reynolds number experimentally.

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Quartz glass high aspect ratio hole by drilling. In the case of the machining of quartz glass, a chipping is occurred caused by the machining stress due to its high hardness and brittleness. On the other hand, electrical discharge machining has a small machining stress. Therefore, in this study, a micro hole machining of the quartz glass was carried. The effect of capacitance of RC discharge circuit was investigated and a high aspect ratio micro hole machining was tried. In this study, an RC discharge circuit was used for machining. The quartz glass was machined using an assisting electrode method, because of its high insulating properties. An Assisting electrode was adhered on the workpiece surface, and the discharge was occurred to the surface. An electrical conductive layer was formed by the thermal decomposition carbon derived from the work oil. A power supply path was formed on the electrical discharge machined surface, and the machining was continued. The removal rate was increased with a decrease in capacitance. And the electrode wear ratio was indicated low in each capacitance. The micro hole drilling of high aspect ratio was carried out by capacitance of 1.1 nF. In this machining, removal rate was decreased as the high machined hole depth.

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A mold material is required strength, machinability, lightness, and corrosion resistance. However, both is difficult for single material. Therefore, a surface treatment technology is demanded. In the EDM, the tool electrode material is adhered to the workpiece. In the case of the using a tungsten tool electrode, it is possible that high hardness machined surface. In this study, in order to obtain high hardness EDMed surface, the effect of discharge current and tungsten powder grain size on the Vickers hardness was investigated. Spark plasma sintered compact was used as the tool electrode. The hardness of the EDMed surface was increased with an increase in discharge current. The coated layer of the EDMed surface was contained by tungsten. The coated layer thickness of the EDMed surface was increased with an increase in discharge current. In the case of the large tungsten powder grain size, the EDMed surface was indicated high hardness.

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This study attempted to reduce the crack on machined surface for Polybenzimidazole (PBI) in slow cutting speed by using orthogonal tool under laser assisted machining (LAM). As traditional cutting method causes the crack on the surface usually, strength of PBI decreases as compared with inherent. Though the condition that cutting temperature is approximately 693K can reduce the crack, it requires extremely fast cutting speed as 2400 m/min, so it's difficult to realize this method in general machine tool. From this experiment, LAM indicated fluid area where there is no crack on surface although cutting speed is as slow as 500 mm/min. In addition, laser irradiation to local area didn't cause heat influence at machined surface. Bringing the laser spot close to the tool is effective in order to spread this fluid area. However, method of changing laser diameter is better way than it for changing distance between laser and tool. As the larger the spot diameter is, the more the temperature becomes uniform, the area of crackless is increased.

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Recently, cutting has replaced grinding in finish processing of hardened steel. However, tool damage is a major problem in high-efficiency operations that use high-speed cutting and high-feed rate conditions rather than the more commonly used cutting conditions. Therefore, a new cutting technique that can realize high-efficiency cutting is desired. In the previous report, processing efficiency has been improved 3 to 5 times compared with conventional cutting by rotary cutting of hardened steel. Furthermore, in order to attain high efficiency, the wear resistance and oxidation resistance of tool material need to improve. In this study, the cutting performance of Al rich coated tool which improved oxidation resistance was investigated on fast cutting speed conditions. Based on the obtained results, the flank wear of conventional TiAlN coated tool and Al rich tool were less than 50μm with cutting speed 1.67m/s even in cutting length 5.0km. Additionally, the each tool wear advanced progressively without flaking. Although the cutting performance of Al rich tool is the same as that of the conditions of cutting speed 1.67m/s even if cutting speed increases to 2.51m/s, conventional TiAlN coated tool indicated serious failure at cutting length 3.0km. It is thought that the difference of the oxidation resistance of both tools influenced the cutting performance.

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This study deals with non-axisymmetric curve surface turning (NACS-Turning). This novel turning method realizes efficient turning of a workpiece which is composed of non-circular surface such as a cam of internal combustions by synchronizing the X axis with spindle rotation at a spindle speed of 750 min-1. In our previous study, we constructed the fundamental machining process for NACS-Turning, and its effectiveness was confirmed. However, since acceleration of the X-axis slide depends on the workpiece profile, it was recognized that the X-axis slide sometimes exceeded its allowable acceleration. Therefore, in that case, a solution which divides the machining process into two times, CW and CCW, is an idea. In this report, the division method considering acceleration excess is proposed.

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The effectiveness of a diamond burnishing method with rotating tool, which is proposed by the authors, is investigated. A developed hybrid-type parallel mechanism with spherical 5-degree-of-freedom range and force control was used as a burnishing machine. A diamond tipped tool, which is rotated by the high-speed-motor spindle, was used as a burnishing tool. A hardened die steel surface was targeted. The fundamental characteristics of the proposed method were evaluated by the surface profile, appearance of the burnishing mark and glossiness of the burnished surface, and the advantages of the proposed method were clarified by comparing with the conventional method, which is without the tool rotation.

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In this research, a polynomial chaos method is utilized for aerodynamic uncertainty analysis of 2D supersonic biplane airfoil. In this method, all uncertain variables / parameters are replaced with a set of orthogonal polynomials, and then governing equations are expanded for each random mode. Finally, uncertainty analysis can be performed efficiently by solving the expanded governing equations directly. The input uncertainties are given on the freestream Mach number and angle of attack as normal distributions. The stochastic distributions of static pressure of the polynomial chaos method show qualitative agreements with full non-linear Monte-Carlo simulation result. The obtained probability density functions of aerodynamic coefficients also show qualitative agreements with that of Monte-Carlo simulation by increasing the order of polynomial chaos.

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