• 천문학회보
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• 제41권1호
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• pp.61.3-62
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• 2016

An asteroid family is a group of asteroidal objects in the proper orbital element space (a, e, and i), considered to have been produced by a disruption of a large parent body through a catastrophic collision. Family members usually have similar surface properties such as spectral taxonomy types, colors, and visible geometric albedo with a same dynamical age. Therefore an asteroid family could be called as a natural Solar System laboratory and is also regarded as a powerful tool to investigate space weathering and non-gravitational phenomena such as the Yarkovsky/YORP effects. We carry out time series photometric observations for a number of asteroid families to obtain their physical properties, including sizes, shapes, rotational periods, spin axes, colors, and H-G parameters based on nearly round-the-clock observations, using several 0.5-2 meter class telescopes in the Northern hemisphere, including BOAO 1.8 m, LOAO 1.0 m, SOAO 0.6 m facilities in KASI, McDonald Observatory 2.1 m instrument, NARIT 2.4 m and TUG 1.0 m telescopes. This study is expected to find, for the first time, some important clues on the collisional history in our Solar System and the mechanisms where the family members are being transported from the resonance regions in the Main-belt to the near Earth space.

• 복식
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• 제64권8호
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• pp.179-190
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• 2014

In traditional costume, colors have been used to express the religion, society, culture, custom, and other aspects of a country. This is mainly due to color being the most conspicuous visual factor of a costume. In Thailand, there is a symbolic color for each day of the week, and the purpose of this study is to contribute to deeper understanding of the Thailand culture in regards to color and its costumes. The study method is as follows: literatures and photos were researched for social and religious background of the seven days Buddha history, which was the source of the color a day culture, symbols and significance of each Buddha were studied and precedent studies were reviewed. The study attempted to investigate the effect of the symbolic color on costumes as it passed down from generations. Originally, the symbolic colors of seven days Buddha in Thailand was a religious component that was exclusive to the upper class. However, it has expanded to the lower classes today. Currently, it obtains an aspect of health and wealth gospel for oneself or others as well as being used to express individual personality because people regard certain color as their symbolic color.

• 치과방사선
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• 제28권1호
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• pp.285-297
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• 1998

This report details a case of 8-year-old girl showing failure of odontogenesis after chemo-radiation therapy for the rhabdomyosarcoma at the age of 4. The observed results were as follows : 1. Past history revealed that she had received for a total radiation dose of 4430cGy, 29 fractions in 6 weeks and chemotherapy with vincristine, actinomycin D and cytoxan, followed as maintenance phase for 2 years. 2. The patient was symptom -free and appointed for the treatment of multiple dental caries. 3. Oral examination showed hypoplastic enamel on whole erupted permanent teeth and showed retarded eruption. 4. Conventional radiograms showed failure of root development including abrupt cessation of root formation and root agenesis, and microdontia, missing teeth, irregular enamel, dislocation of the impacted teeth. Additional finding showed good healing bone pattern on the left mandibular ramus and angle area. 5. Cephalometric analysis revealed failure of bite raising due to incomplete eruption of all the first molars and made it possible to suspect entrapped mandibular growth and then Class II tendency growth. 6. There was correlation between the time of chemo-radiation therapy and the damage of the teeth.

• 한국지진공학회논문집
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• 제19권1호
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• pp.1-11
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• 2015

In order to perform a soil-isolation-structure interaction analysis of seismically isolated nuclear power plant (NPP) structures, the nonlinear behavior of a seismic isolation system may be converted to an equivalent linear model used in frequency domain analysis. Seismic responses for seismically isolated NPP containment structures subjected to a simple artificial acceleration history and different site class earthquakes are evaluated for the equivalent-linear and nonlinear models that have been applied to lead-rubber bearing (LRB) modeling. It can be observed that the maximum displacements of the equivalent linear model are larger than that of the nonlinear model. From the floor response spectrum analysis for the top of NPP containment structures, it can be observed that the spectral acceleration of an equivalent linear model at about 0.5 Hz frequency is about 2~3 times larger than that of a nonlinear model.

• 천문학회지
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• 제36권3호
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• pp.123-144
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• 2003

The 8m class telescopes in the ground-based optical astronomy together with help from the ultra-sharp eye of the Hubble Space Telescope have enabled us to observe forming galaxies beyond red shift z = 5. In particular, more than twenty Ly$\alpha$-emitting galaxies have already been found at z > 5. These findings provide us with useful hints to investigate how galaxies formed and then evolved in the early universe. Further, detailed analysis of Ly$\alpha$ emission line profiles are useful in exploring the nature of the intergalactic medium because the trailing edge of cosmic reionization could be close to z $\~$ 6 -7, at which forming galaxies have been found recently. We also discuss the importance of superwinds from forming galaxies at high redshift, which has an intimate relationship between galaxies and the intergalactic medium. We then give a review of early cosmic star formation history based on recent progress in searching for Ly$\alpha$-emitting young galaxies beyond red shift 5.

• Archives of Plastic Surgery
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• 제34권4호
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• pp.501-503
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• 2007

Purpose: The authors report unusual one case of a patient presenting with maxillary sinus mucocele who had underwent Lefort I procedure 7 years ago. Methods: Case report and literature review Results: A 25 year old man came to us with fullness, pain and nasal obstruction on his left cheek area. He had a history of multiple operations due to cleft lip and palate since birth. Two jaw surgery was performed for correcting class III malocclusion 7 years ago. Computed tomography showed haziness, and fluid filled cystic mass on left maxillary sinus. Nasoendoscopy revealed the bulging of inferior turbinate and mucosa coincided in medial wall of maxillary sinus. Antrostomy with Caldwell-Luc approach was performed. Mucin contaning brownish exudate was leaked out. Severe inflammation of maxillary inner wall and exposure of 2 screws fixed previously were noticed. The curettage and marsupialization were accomplished. The symptoms of patient were improved after that procedure. Conclusion: Maxillary sinus mucocele is related with Lefort I procedure and it may occur even long after that procedure.

• 공학교육연구
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• 제22권5호
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• pp.29-36
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• 2019

Here we analyze a case of redesigned course named "Prospect of Nuclear Engineering" as an example of student-entered education which came to the fore of university education innovation. This course was reformed from lecture-based to student-centered class by changing the context as follows: Stimulating students by addressing various problems or episodes behind scientific and mathematical concepts in the history; Offering experimental project to perceive the importance of differential equations; Exploring the research status and issues of nuclear engineering and the ways of attacking them by discipline; Discussing the public acceptance of nuclear power plants. Small group activities using 'small group discussion' and 'peer-learning' have been applied in this course to enhance students' critical and creative ability. In the survey, students rated highly in the fact that they could actively interact with the peers and that they could think for themselves through 'small group discussion' and 'peer-learning' which is not just the way of conveying knowledge.

• 철학연구
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• 제146권
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• pp.79-114
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• 2018

이 글은 세간에 잘 알려져 있지 않은, 그렇지만 한국의 실천철학사에서 반드시 유념해 봐야할 인물, 무엇보다 '철학적 반면교사(反面敎師)'로 삼아야할 사회철학자로서의 김두헌의 철학(함)의 본질적 실상을, 그의 실천철학 체계의 핵심 얼개를 이루고 있는 '가치론적 변증법'에 초점을 맞추어, 비판적으로 규명해 보는데 일차적 목적이 있다. 이러한 작업은 해방 이후 이제껏 70여 년 이상 한국 사회에 군림하며 무소불위의 통치 권력을 행사해온 소위 '친일 독재 세력'의 정치적 지배 권력을 비호하고 정당화한 주도적인 이데올로그 가운데 한 사람으로서 그 철학자적 역할을 수행해 나갔던 김두헌의 실천적 철학함 방식과 그 철학적 여정에 관한 비판적 고찰을 통해 이루어질 것이다.

• 기록학연구
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• 제62호
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• pp.109-138
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• 2019

국가기록원 나라기록관은 2008년 개관 이후부터 현재까지 기록문화프로그램을 운영하고 있으며, 대통령기록관이 세종으로 이전하기 전에는 대통령기록관과 나라기록관이 함께 기록문화프로그램을 공동으로 운영하기도 하였다. 기록문화프로그램은 국가기록원 나라기록관 뿐 아니라 행정기록관, 역사기록관, 대통령기록관에서도 운영하고 있으며, 각 소속기관의 실정에 따라 운영횟수 및 기획, 구성 등의 방식은 다소 차이가 있다. 여기서는 성남 나라기록관에서 운영되어온 프로그램 구성과 내용 등 운영 현황을 파악하고, 이에 대한 분석을 토대로 앞으로 지향해야 할 아카이브의 기록문화프로그램의 방향에 대한 제언을 하고자 한다.

• Structural Monitoring and Maintenance
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• 제7권4호
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• pp.367-392
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• 2020

The specific characteristics of near-field earthquake records can lead to different dynamic responses of bridges compared to far-field records. However, the effect of near-field strong ground motion has often been neglected in the seismic performance assessment of the bridges. Furthermore, damage to horizontally curved multi-frame RC box-girder bridges in the past earthquakes has intensified the potential of seismic vulnerability of these structures due to their distinctive dynamic behavior. Based on the nonlinear time history analyses in OpenSEES, this article, assesses the effects of near-field versus far-field earthquakes on the seismic performance of horizontally curved multi-frame RC box-girder bridges by accounting the vertical component of the earthquake records. Analytical seismic fragility curves have been derived thru considering uncertainties in the earthquake records, material and geometric properties of bridges. The findings indicate that near-field effects reasonably increase the seismic vulnerability in this bridge sub-class. The results pave the way for future regional risk assessments regarding the importance of either including or excluding near-field effects on the seismic performance of horizontally curved bridges.