In this work, tightening axial force, Vickers hardness and microstructure of torshear-type high strength bolts heat-treated in various conditions were studied. As a result, it was found that the bolts heated at up to 673K did not show a significant decrease in tightening force and Vickers hardness and the bolts heat-treated at the temperature higher than 673K did. This is because the tempering temperature for the bolts after quenching in manufacturing process is close to 673K. However, the bolts heated at 1073K and subsequently water-quenched showed a significant increase in Vickers hardness due to the formation of martensite phase by quenching from austenite phase. Moreover, the slip factors of friction-type high strength bolted joints with pre-heated bolts were studied. As a result, it was found that the slip factors almost kept constant when using the bolts heated at up to 673K, but the factors fell below 0.5 when using the bolts heated at 773K and 873K.

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The purpose of this study was to consider expertise among social workers by identifying attributes, antecedents and consequences of expertise. A literature review was conducted based on the findings of 13 articles which expressed the concept of expertise among social workers. The extracted attributes of expertise in social workers included respect for clients, deep understanding through advanced interview skills, flexible relationships between clients, specific skills in difficult situations of clients, multiple information gathering and planning, approach to the environment by using multiple social resources, other cooperation of organizations and multiple professionals, rich expertise, metacognition and wide vision, evidence-based practice and prospective supports. Antecedents of expertise in social workers included enthusiasm for social work, self-improvement and self-reflection. The consequences of expertise in social workers included establishment of self-identity, trust and reputation of coworkers, wide network of contacts and human resource development. The findings of the study may aid in the development of vocational rehabilitation service providers.

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Electric precipitators have used widely for industrial use. Some designs are built around empirical formulas from some experimental results of past researchers, and there is enough data to calculate the discharge current, charging, and dust collection processes. In this study, we made an electric precipitator on a desk and operated it on numerical calculation software, and examined whether the performance could be evaluated. The performance evaluation for transient operation will be discussed in the next report. In this report, while comparing the calculation process and the problems of the electrostatic precipitator, it was compared with the experimental results. The numerical calculation software used MATLAB / Simulink, however it is also possible to use Excel to perform with steady-state operation.

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Aim of using an electrostatic precipitator, there is reducing the generation emission under emission standard for industrial using. On the other hand, an air cleaner in home use, it is required to lower the concentration in the closed space with low power. Corona discharge is used in the pre-charger of the electrostatic precipitator, and the ozone is emitted. The increase in ozone concentration must also be required in the enclosed space. In this study, the reduction of the particle concentration when the electric precipitator was applied to the open and the closed spaces with calculated using MATLAB/Simulink. The differential equations were modeled and calculated. It is considered that this model can be developed to a model-based control of the electrostatic precipitator in the future.

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This study checked the instruction method to perform 5S activity for students of the production of ability for Okinawa occupation development colleges electricity system technology department voluntarily. A training method reproducing a shop floor for education training in the applied course of the ability for occupation development college was used. The instruction method that assumed that a student is engaged in the hygiene management of the shop floor safe as a leader in the future in that is necessary. Therefore I performed two training about instruction of the 5S activity for trying it as a sample and confirmed the effect because questioner survey did a change of the consciousness of the student. This study shows a curriculum, the teaching materials, the instruction method used for the trial program for 5s activity.

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