Patterned fine particles enable a lot of applications. Hydrophobic/hydrophilic patterning with groove on a substrate is effective in site-selective dip coating in which suspension including particles spreads on desired area and then particles assemble with the evaporation of solvent. This paper aims to construct a model of the self-assembly process including the conditions of assembly start or not on such substrate. We investigated the height and shape of suspension spreading over hydrophilic/hydrophobic patterned groove. In addition, critical local contact angle which determines the self-assembly will start or not was modeled. In order to verify this hypothesis, we examined both effects of change in contact angle on hydrophobic region and groove depth on the particles assembly. It was found that the width can be estimated based on the local contact angle of the spreading profile.

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Ultra-precision machine tools for fabricating optical lens and lens molds require highly accurate positioning. However, one concern is that, depending on the workpiece size, fly-cutting using conventional machine tools can often require a large amount of time. To solve this problem, we have developed an ultra-precision 5-axis machine tool, and evaluated its processing performance during free-form, high-speed surface machining of a workpiece with high-precision contour control. We successfully demonstrated a non-rotational cutting process that resulted in a surface roughness of within 2 nm and a form accuracy of within 0.1μm. The processing time was less than half that required by a conventional fly-cutting process. The performance of the machine tool and the results of an evaluation of the machined mold are reported in this paper.

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This paper presents a simple machining method for trimming of CFRP (Carbon Fiber Reinforced Plastic) with an end mill, which can realize significantly high machining efficiency and long tool life with good surface finish. It seems that the conventional problems in the trimming process, such as delamination of trimmed edges, machining efficiency and tool wear, are caused by applying conventional milling conditions for metals without considering strong anisotropic material property of CFRP. In the proposed method, lead and helix angles of the end mill are selected appropriately so that the milling force suppresses the delamination. In order to finish the upper and lower edges on this concept, the upper and lower surfaces are machined separately at different lead angles. It is confirmed experimentally that the delamination is suppressed and tool life is extended at appropriate lead/helix angles, even when the feed rate (machining efficiency) becomes more than ten times higher than the conventional rate.

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The objyective of this investigation is an invention of theory and technics on high precision cylindrical machining with combining ultrasonic vibration cutting on thrust force direction, and superposition superfinishing process. In this report, it is analyzed that multiple precision cylindrical machining is possibly achieved with using insensitive vibration cutting mechanism on thrust force direction, and microgroove self control mechanism on superposition superfinishing . The experiments for precision cylindrical machining have be done, after some testinng for deciding a suitable condition on ultrasonic vibration cylindrical terning on thrust force direction , and superposition superfinishing. In the multiple experiments, roundness 0.3μm∼0.6μm, surface roughness 0.1μmRz∼0.2μmRz could be achieved for aluminum alloy, brass and carbon steel. These results indicates that multiple machining system is appropriate for precision cylindrical machining.

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For machining molybdenum (Mo), Electrical Discharge Machining (EDM) is generally used. However, a molybdenum carbide (MoC and Mo₂C) layer with high hardness and brittleness is formed by EDM in kerosene oil. Therefore, many cracks occurred in the EDMed surface. In this study, in order to obtain crack-less surface, EDM of Mo with silicon (Si) electrode and machining in deionized water have been carried out to determine the effect of crack generation. In case of machining with Si electrode in kerosene oil, cracks in the recast layer were decreased. In case of using Cu electrode in deionized water, many cracks occurred in the base material and recast layer. The cracks in the base material might generate by crystal grain boundary embrittlement. In contrast, using Si electrode, the EDMed surface indicated crack-less. In addition, the recast layer contained molybdenum silicide (MoSi₂). To clarify the effect of recrystallization on cracks in the base material, heat conduction equations were solved to predict the depth of recrystallization region on each setting discharge current. The calculated recrystallization region was equal to depth of cracks in the base material.

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This paper describes about a root cause analysis method in product quality control, especially, when failure data quantity is extremely small. In the root cause analysis, t-test, F-test and Kullback-Leibler (KL) divergence are possible indicators to quantify a difference between pass and failure data distribution. But those are not stable on small sample data such as less than 10 samples. To solve the problem, we have proposed a failure occurrence probability as an estimator of KL divergence. The failure occurrence probability is an intermediate state of KL divergence because the limit of occurrence probability becomes KL divergence.
In the evaluation of rank correlation with actual data, the proposed method shows a highest correlation on 5 sample and 50 sample test cases comparing with other methods. This results comes from the failure occurrence had a smaller variance than KL divergence. In conclusion, the occurrence probability has a possibility to estimate a distribution difference, stably on the small sample data.

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In the 1st report of this investigation, geometric quantities such as the tool-workpiece contact region, distribution of undeformed chip thickness along the cutting edge and the area of cutting cross-section, and cutting speed were analyzed for slot milling where the tool is tilted by one or two axes. Then the variation of these quantities with the tool tilting angle was shown. Furthermore cutting forces under various tool tilting angles were predicted by using a cutting model proposed in previous papers, and relationships among the tool attitudes, the cutting forces, cutting speed and the geometric quantities above-mentioned were systematically explained. In the 2nd report, pick-feed milling process was discussed, and tool deflection was analyzed by applying the predicted cutting forces and a finite element model of a ball end mill for elastic analysis developed in the previous paper. In this paper, the machining error in the pick-feed milling, in which the tool tilting angle ν is specified in the plane perpendicular to the direction of the tool motion, is estimated on the basis of the analytical results of the tool deflection. As a result, it is clarified that where the pick-feed is given to the left side of the direction of the tool motion and the tilting angle ν is specified by a large negative angle, the machining error in pick-feed milling process reduces and increase of the cutting speed is obtainable.

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Nanoparticles are attractive materials in the area of nanotechnology, and there is a need to measure the particle size accurately and easily. We suggest a novel particle sizing method based on fluorescence polarization. Particle size evaluation can be achieved from measuring the rotational diffusion coefficient which is sensitive to the particle size. We develop the rotational diffusion coefficient measurement system using fluorescent DNA probe. We verify the feasibility of proposed method by a fundamental experiment. We measure the rotational diffusion coefficient of gold nanoparticle whose diameter is 8.2nm. The rotational diffusion coefficient decreases by 50% compared to the reference value in the measuring range. The result indicates that nanoparticle, whose diameter is as small as 8.2nm, can be measured.

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