• Journal of Technologic Dentistry
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• v.36 no.2
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• pp.91-96
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• 2014

Purpose: The purpose of this study was evaluate the validity of polyurethane model fabricated by intra oral scanning method. Methods: Ten sam cases of stone models were manufactured from master model, and polyurethane models were made with the intra oral scanning and CNC milling method. One examiner individually measured 6 distances(intercanine distance, intermolar distance, two dental arch lengths(right, left) and two diagonal of dental arch lengths(right, left) on the stone models and the polyurethane models. The Mann-Whitney U test(${\alpha}$=0.05) were used for statistical analysis. Results: The mean difference between measurements made directly on the stone models and those made on the polyurethane models was 0.31-0.38mm. No statistically differences between the two groups were founded 4 distances(p>0.05), but 2 distances were statistically significant(p<0.05). Conclusion: Stone models showed larger than polyurethane models fabricated by intra oral scanning method.

• Publications of The Korean Astronomical Society
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• v.31 no.2
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• pp.21-34
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• 2016

There were two books on astronomy published in 1908. One is "Astronomy (天文學)" written by Jeong, Yeong-Taek (鄭永澤, 1874 ~ 1948), an educator. The other is "Introduction to Astronomy(텬문략 )" written by William Martyn Baird (裵偉良, 1862 ~ 1931), an American missionary. It was known that these two books were translated into Korean as astronomical textbooks of the Korean Empire. We investigated the life of translators, the motivation of writing textbook, and the translators' specialty in astronomy. We also compared the two books in terms of content, orthography of terminology, scale of units, and so forth. We suggest that these books were really utilized as textbooks of astronomy in the modern school in the early $20^{th}$ century in Korea. We also conclude that in astronomy education these two textbooks bridged the gap between the traditional Chinese astronomy of the middle age and modern astronomy from the West.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.56.4-57
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• 2017

The GMT-Consortium Large Earth Finder (G-CLEF) is the very first light instrument of the Giant Magellan Telescope (GMT) to be commissioned in 2022. The instrument is a fiber feed, optical band echelle spectrograph that is capable of extremely precise radial velocity measurement. Korea Astronomy and Space Science Institute (KASI) has been involved in the development of the G-CLEF as one member of the international consortium consisted of five astronomical institutes including Smithsonian Astrophysical Observatory (SAO), Observatories of the Carnegie Institution of Washington (OCIW). It is scheduled to have KASI side Critical Design Review in December 2017. In this presentation we will report the recent progress on the critical design activities for the G-CLEF Flexure Control Camera (FCC).

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.48.2-48.2
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• 2017

우리는 문화재청에서 제공한 보물 840호의 3D 스캔 자료를 이용하여 이 해시계의 위도와, 영침의 길이와 형태, 그 위치에 대해 분석하였다. 국립고궁박물관에는 조선후기 돌널판에 제작된 지평일구가 남아있다. 보물로 지정된 두 유물 중 840호에 새겨진 신법지평일구라는 명문에 의거하여 이 해시계 명칭이 사용되었다. 서양의 구면천문학을 적용하여 제작된 이 지평일구는 단지 시각선과 절기선이 새겨져 있고, 그 밖에 핀 모양의 홈과 깊은 구멍 하나가 흔적으로 남아 있다. 우리는 지평일구의 시각선이 수렴하는 점을 직교좌표의 원점으로 삼았다. 3D 스캔 자료에서 시각선의 연장선은 한 점이 아닌 원점 근처에서 수 mm 이내에서 분산되었다. 각 시각선마다의 원점을 설정하여 계산한 해시계의 위도는 평균 $37^{\circ}\;15^{\prime}{\pm}26^{\prime}$을 보였고, 이는 보물 840호 명문의 37도 39분과 24'의 차이를 나타내었다. 우리의 분석에 따르면 시반의 구멍은 영표가 서있는 위치였으며, 영표의 길이는 $43.7{\pm}0.7mm$로 핀 모양 홈의 길이인 43.1 mm에 근접하였다. 이를 통해 이지평일구는 북극을 지시하는 삼각영표가 아닌 수직의 핀 모양의 영침이 설치된 것을 확인할 수 있었다.

• Korean Journal of Biological Psychiatry
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• v.13 no.2
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• pp.59-69
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• 2006

Bidirectional relationships exist between cancer and depression; the prevalence of depression in cancer patients is higher than in the general population, and depression predicts cancer progression and mortality. The mechanisms through which depression contributes to the progression of cancer are related with dysregulation of the hypothalamic-pituitary-adrenal axis and impairment of immune function. However, depression in cancer patients tends to be underdiagnosed and not appropriately treated. The methods of diagnosis and assessment of depression in cancer patents have been debated because physical symptoms of depression mimic both cancer symptoms per se and the side effects of cancer treatment. Many studies have shown that various psychosocial and/or pharmacological interventions are effective at improving de-pressive symptoms and quality of life in cancer patients. Furthermore, antidepressant treatments are effective for various physical symptoms related to cancer, such as fatigue, anorexia, pain, hot flashes, and itching. This article reviews and discusses current knowledge about depression in cancer patients.

• BMB Reports
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• v.48 no.8
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• pp.479-484
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• 2015

In this study, we report that one of the antimicrobial peptides scolopendrasin VII, derived from Scolopendra subspinipes mutilans, stimulates actin polymerization and the subsequent chemotactic migration of macrophages through the activation of ERK and protein kinase B (Akt) activity. The scolopendrasin VII-induced chemotactic migration of macrophages is inhibited by the formyl peptide receptor 1 (FPR1) antagonist cyclosporine H. We also found that scolopendrasin VII stimulate the chemotactic migration of FPR1-transfected RBL-2H3 cells, but not that of vector-transfected cells; moreover, scolopendrasin VII directly binds to FPR1. Our findings therefore suggest that the antimicrobial peptide scolopendrasin VII, derived from Scolopendra subspinipes mutilans, stimulates macrophages, resulting in chemotactic migration via FPR1 signaling, and the peptide can be useful in the study of FPR1-related biological responses. [BMB Reports 2015; 48(8): 479-484]

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.11 s.254
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• pp.1084-1092
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• 2006

Shape optimization of airfoil in WIG craft has been performed by considering the ground effect. The WIG craft should satisfy various aerodynamic characteristics such as lift, lift to drag ratio, and static height stability. However, they show a strong trade-off phenomenon so that it is difficult to satisfy aerodynamic properties simultaneously. Optimization is carried out through the multi-objective genetic algorithm. A multi-objective optimization means that each objective is considered separately instead of weighting. Due to the trade-off, pareto sets and non-dominated solutions can be obtained instead of the unique solution. NACA0015 airfoil is considered as a baseline model, shapes of airfoil are parameterized and rebuilt with four-Bezier curves. There are eighteen design variables and three objective functions. The range of design variables and their resolutions are two primary keys for the successful optimization. By two preliminary optimizations, the variation can be reduced effectively. After thirty evolutions, the non-dominated pareto individuals of twenty seven are obtained. Pareto sets are all the set of possible and excellent solution across the design space. At any selections of the pareto set, these are no better solutions in all design space.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.286-291
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• 2001

Most cracks in the structure occur under mixed mode loadings and those propagation depend on the stress ratio very much. So, it is necessary to study the fatigue behavior under mixed mode loading as stress ratio changes. In this paper, fatigue crack propagation behavior was investigated respectively at stress ratio 0.1, 0.3, 0.5, 0.7 and we change loading application angle to $0^{\circ},\;30^{\circ},\;60^{\circ}$ to apply various loading. mode. The mode I and II stress intensity factors of CTS specimen used in this study were calculated by displacement extrapolation method using FEM(ABAQUS). Using both the study through the experiment and the theoretical study through FEM analysis, we studied the relation between crack propagation rate and stress intensity factor range at each loading mode due to the variation of stress ratio. Also, when the crack propagated under given stress condition and given loading mode condition, we studied what the dominant factors of the crack propagation rate were at each case.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.137-142
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• 2003

In this study, the propagation behavior of fatigue crack effected hole defects was investigated under mixed-mode I+II loading. To create mixed-mode stress field at crack tip, the compact tension shear (CTS) specimen and loading device were used in this tests. The propagation experiments of fatigue crack were performed by changing of the loading application angle(${\phi}$) and the distance(L) estimated from pre-crack tip to hole center located side by side by side with a pre-crack. As L changes, the variation for propagation aspect of fatigue crack, fatigue life and crack propagation rate were examined under mixed-mode loading. Under mixed-mode loading, the propagation rate of fatigue crack increased while the propagation direction changed dramatically because of the interference of hole defects.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1586-1591
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• 2006

조선사는 선주와의 계약에 의한 수주 생산방식으로 계약시 명시된 작업시작일, 도크작업시작일 진수일, 인도일을 지키기 위한 공정별 목표 생산완료일을 결정하게 되고, 각 공장별로 목표 생산완료일을 지키기 위한 일정계획을 수립하게 된다. 생산되는 선박은 선종, 선형에 따라 구성되는 블록의 수가 다르고 그 형태도 매우 다양하다. 그러므로 선박을 건조하기위해 제작되는 블록의 정확한 작업공기와 공수를 예측하기가 매우 어렵다. 본 논문에서는 불확실한 작업공기와 공수를 이용하여 작업장의 공간제약을 고려한 일정계획을 수립하는 문제에 대하여 기존의 공간제약 문제에 대한 연구에서 나아가 실행 단계에서의 운영프로세스를 개선하여 적용하는 연구를 수행하였다. 이번 연구의 결과로 목표 생산계획과 부서계획, 실행 실적을 과거 데이터와 비교분석 하여 개선된 운영프로세스의 효과를 검증하였다.