• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.6
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• pp.71-75
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• 2006

The application of focused ion beam (FIB) technology in micro/nano machining has become increasingly popular. Its usage in micro/nano machining has advantages over contemporary photolithography or other micro/nano machining technologies such as small feature resolution, the ability to process without masks and being accommodating for a variety of materials and geometries. The target of this paper is the analysis of FIB sputtering process according to tilt angle, dwell time and overlap for application of 3D micro and pattern fabrication and to find the effective beam scanning conditions using Taguchi method. Therefore we make the conclusions that tilt angle is dominant parameter for sputtering yield. Burr size is reduced as tilt angle is higher.

• International Journal of Fluid Machinery and Systems
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• v.10 no.1
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• pp.54-62
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• 2017

The Savonius wind turbine has a lower performance than other types of wind turbines which may attract more study focus on this turbine. This study aimed to improve wind turbine performance by combining a conventional blade with an elliptical blade into a combined blade rotor. The analysis was performed on three blade models in computational fluid dynamics (CFD) using ANSYS_Fluent Release 14.5. Then the results were verified experimentally using an open wind tunnel system. The results of the numerical simulation were similar to the experimental and showed that the combined blade rotor has better dragging flow and overlap flow than the conventional and elliptical blade. Experimental verification showed that the combined blade was to increase the maximum coefficient of power ($Cp_{max.}$) by 11% of the conventional blade and to 5.5% of the elliptical blade.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.14 no.2
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• pp.182-185
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• 2014

GM1 gangliosidosis is a rare autosomal recessively inherited metabolic disease due to deficiency of ${\beta}$-galactosidase caused by mutations in the GLB1 gene. There have been three clinical subgroups in GM1 gangliosidosis, however it is difficult to differentiate because there is considerable overlap between classical phenotypes and clinical and imaging findings among the subgroups. Here, we report a Korean girl with type 2 GM1 gangliosidosis, who showed dysostosis multiplex and progressive neurological deterioration. Developmental regression was first noted at the age of 9 months, and she was diagnosed as GM1 gangliosidosis by ${\beta}$-galactosidase enzyme analysis and GLB1 mutation analysis at the age of 16 months.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.535-546
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• 2017

국가 R&D 사업에 대한 예비타당성조사 시 R&D 중복성에 대한 검토는 중복된 투자를 방지하여 재정 투자의 효율성을 높이는데 중요하다. 본 연구에서는 예비타당성조사 담당자들을 대상으로 중복성 검토에 대한 중요요인, 개선사항, 판단기준, 판단주체에 대한 설문조사 분석을 진행하였고, 외부 전문가 그룹의 인식차이와 비교하였다. 설문조사 결과에 대한 통계 분석을 통해 중복성 검토에서 가장 중요한 요인은 '중복성 판단기준, 시스템의 데이터베이스 및 검색 알고리즘'으로 확인되었고, 3가지 요인에 대한 개선이 중복성 검토를 개선하는데 가장 중요함을 확인하였다. 또한 다중회귀분석을 통해 주요 요인들이 중복성 검토결과의 정확성에 미치는 영향성을 분석하여 요인들의 유의성에 대해 확인하였다. 본 연구를 통해 예비타당성 조사 시 R&D 중복성에 대한 검토가 향후 어떤 방향으로 개선되어야하는지에 대해 시사점이 제시된다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.71-74
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• 2008

In order to resolve the problems which appear after the clean large ingot production process, the impurities which are involved in the steel smelting process should be removed by developing cleaner materials. Through the rationalization of cogging process that is the first forging process of large ingot the quality is to be improved. For the sake of the optimization of an open die forging process and the improvement of the subject matter frequency ratio, a hazard precise die forging process must be developed and a Near Net Shape Forming accomplished. As a result, energy can be reduced by minimizing an after control process. In order to produce large axes and other forming parts, processing techniques are to be developed. In this context, this paper is a study about a reduction ratio, dies width ratio and rotary angles, the amount of overlap, and intends to analysis cogging processes, utilizing Deform-3D cogging module

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.616-621
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• 2005

Most machine element, such as gears and bearings, are operated in the mixed lubrication region. Contact between two asperities has an effect on machine life by increasing local pressure. To estimate fatigue lift exactly, asperity contact should be considered as a factor of fatigue liff because this happening produce friction, abrasion and make flash temperature. In this paper, asperity contact is considered as a result of film breakdown when lubricant pressure is not enough to separate two asperities. Contact pressure is calculated to asperity overlap region and added to lubricant pressure. For this model, numerical procedure is introduced and the result on surface roughness and velocity for wheel bearing is presented. Results of EHL analysis for wheel bearing show that asperity contact is occurred at the edge of EHL conjunction where has a insufficient lubricant pressure to separate two surface.

• International Journal of Highway Engineering
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• v.14 no.1
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• pp.95-102
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• 2012

This study has been conducted to characterize the relations between the accident rate and the overlap section elements where the horizontal alignment and vertical alignment are overlapped. The researches were performed on Horizontal curve sections of 4-lane highways with 100km/h of design speed and speed limit. Korea Highway Corporation's Geographic Figurative Information System was adopted for geometric organization and Highway Traffic Accident Statistics was used. The results reveal that sections made of a single slope without vertical curve has greater accident rate than those with vertical curve, and that sections with 1 vertical curve are higher in the accident rate than those with over 2 vertical curve. For the sections with 1 vertical curve, SAG sections are higher than CREST sections and for the previous straight section of horizontal curve are higher than curved ones. In particular, when the road surface is wet, the accident rate is closely related with SAG vertical curves or leftward horizontal curved sections. This study will have meanings that it proposes the importance of design of road alignment by taking consideration of 3D synthetic alignment conditions for improvement of the road safety.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.4
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• pp.30-39
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• 2010

Since Diffusion tensor from Diffusion Tensor Magnetic Resonance Imaging(DT-MRI) is so sensitive to noise, the principle eigenvector(PEV) calculated from Diffusion tensor could be erroneous. Tractography obtained from PEV could be deviated from the real fiber tract. Therefore regularization process is needed to eliminate noise. In this paper, to reduce noise in DT-MRI measurements, the Dyadic Sorting(DS) method as regularization of the eigenvalue and the eigenvector is applied in the tractography. To resort the eigenvalues and the eignevectors, the DS method uses the intervoxel overlap function which can measure the overlap between eigenvalue-eigenvector pairs in the $3\times3$ pixel. In this paper, we applied the DS method to the three-dimensional volume. We discuss the error analysis and numerical study to the synthetic and the experimental data. As a result, we have shown that the DS method is more efficient than the median filtering methods as much as 79.97%~83.64%, 85.62%~87.76% in AAE, AFA respectively for the corticospinal tract of the experimental data.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.872-880
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• 2016

The purpose of this study is to find the research trends relating to flipped learning through keyword network analysis. For investigating this topic, final 100 papers (removed due to overlap in all 205 papers) were selected as subjects from the result of research databases such as RISS, DBPIA, and KISS. After keyword extraction, coding, and data cleaning, we made a 2-mode network with final 202 keywords. In order to find out the research trends, frequency analysis, social network structural property analysis based on co-keyword network modeling, and social network centrality analysis were used. Followings were the results of the research: (a) Achievement, writing, blended learning, teaching and learning model, learner centered education, cooperative leaning, and learning motivation, and self-regulated learning were found to be the most common keywords except flipped learning. (b) Density was .088, and geodesic distance was 3.150 based on keyword network type 2. (c) Teaching and learning model, blended learning, and satisfaction were centrally located and closed related to other keywords. Satisfaction, teaching and learning model blended learning, motivation, writing, communication, and achievement were playing an intermediary role among other keywords.

• The Research Journal of the Costume Culture
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• v.24 no.5
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• pp.561-576
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• 2016

Born in the 19th century as an intermediate between the past and the future, steampunk provides a strong feeling of fantasy. The objective of this research is to understand the utilization of steampunk in all realms through an in-depth literature review and empirical study. Taking the findings as a foundation, we will analyze examples shown in fashion designs that are put into real production, and those designs that can provide inspiration for further design development. The research methodology will constitute a major analysis of advanced research, internet materials, and literature. Photo materials will be collected from professional websites for steampunk. The product method such as follows. Firstly, we will classify the internal meaning of characteristics in steampunk that are similar to the characteristics that are being researched, then take it as the standard and arrange to integrate all five features: restoration, pluralism, duplicity, resistibility and abnormality. We will spread out the design based on images from advanced research. Secondly, in order for to design a steampunk product, I decided on four themes: devastated environment, brutal wars, cool-headed machinery, and the overlap of the future and the past. Inspiration was acquired from representative movies and animations featuring steampunk. Thus, new directions for fashion design with steampunk features can be discovered. It raises the feasibility of this combination in modern society. In the future with the development of technology, it functions as a design that is easy for users to approach.