• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.311-323
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• 2001

One of the various mechanics used to treat unilateral Class II malocclusion is head gear with asymmetric face bow. We made the finite element models of unilateral Class II maxillary dental arch and power arm asymmetric face bow. We designed this experiment to observe stress distribution of periodontal ligament, reaction force, and displacement and to understand force system, so to predict the therapeutic effect. On the basis of computerized tomograph of maxillary dental arch of 25 years old male with normal occlusion without extraction and orthodontic treatment history, we made finite element models of maxillary dental arch and periodontal ligament. Then we modified that model to unilateral maxillary Class II malocclusion model of which maxillary left molar displaced mesially. Also, We made finite element model of asymmetric face bow of which right outer bow shorter than left by 25mm(RMO, Penta-FormTM/Medium size, 0.045 inch iner bow, 0.072 inch outer bow). After that, retraction force of 250g, 300b, 350g were applied to maxillary first molar. We concluded as follow. 1. The Net force that both maxillary first molars were received increased as the retraction force increased. Mesially positioned tooth received more force than normally positioned tooth. But, both tooth were received distal force, so distal movement occured. 2. Both tooth received buccal lateral force. In analysis of force element, as the retraction force were increased, force of X-axis at mesially positioned tooth decreased, and force of X-axis at normally positioned tooth increased. so lateral force component moved to the side received less force from more force. 3. There were rotation, tipping with distal movement in maxillary first molar. As retraction force were increased, rotation and tipping also increased. More tipping and rotation occured at the side received more force, that is, mesially positioned tooth. Though it Is small change, displacement of same pattern occur in normally positioned tooth

• Journal of the Korean Society of School Health
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• v.8 no.2
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• pp.293-303
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• 1995

Health has occupied a position of importance in the human history, whether it be in the East or in the West, and it is a subject in which people have been constantly interested. The concept of health has changed continuously as the society has developed, industrialized and become more structured. The perception of health concept can be an esential factor which is to determine the health behaviors. This study is a descriptive inquiry done to identity high school students' perception of health and what they do as health behaviors. The subject consisted of 503 voctional high school seniors, 129 boys and 374 girls, from a school located in An-san Si, kyong-gi Do. The instruments used for this study were open-ended questionnaires and data were collected by having the students fill out the questionnaires which took 10 minutes, in their first class, April 6, 1995. The collected materials were classified and recorded on the cards according to each question using the terms which students had written. After putting statements which had common meanings together, the representative categories were labelled. The results obtained are as follows. 1. Categorizing and labelling of health concepts What high school students descripted as health concepts were classified as the absence of illness, physical comfort, strong physical strength and physique, not having a deformity, resisting power, self control mental-rest(or psychological comfort), wholesome ideas, self-control, harmony in body and in mind, maintenace of daily life, pleasant life, good friends, peaceful family life and realizing objectives. 2. Categorizing and labelling of health behaviors These were classified as preventive life, good dietary habits and regimen, maintenance of clean body, exercises, preventing obesity, rest, environmental balance or control of environment, limit one's tastes, making use of leisure, peaceful mind, sound thought and regular living habits. The result indicates that the health concepts were positive and included not only absence of illness but also harmony in body and in mind and pleasant life; health behaviors which had high frequency were good dietary habits and regimen, exercises and sound thought. It is hoped that these findings well serve as practical references for teachers when they counsel with, and provide the students with guidance programs which include health care.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.67-76
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• 2017

To conduct research using small group learning with advanced technology in school, small group collaborative learning was conducted in virtual reality called Second Life for high school history class to verify the effects of the role of group members (leader, group member) in collaborative learning activities in this study. Two classes of the second grade of high school were selected randomly and 20 groups were also randomly assigned, and each group was consisted of three members (1 leader and two group members). Academic achievement and satisfaction with academic activities were used to verify the effect of the role as measurement tools, and collected quantitative data were tested by independent sample t. As a result, it was found that performing the role of leader in collaborative learning activities in virtual reality was effective in promoting enhancing students' academic achievement and increasing satisfaction level. Lastly, utilization and improvement of small group collaborative learning using virtual reality in the field of education were discussed.

• Communications of Mathematical Education
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• v.30 no.2
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• pp.139-159
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• 2016

This study is the field of mathematics education on the assumption that they can extend outside the classroom. Recent mathematics education is increasing the importance of field experience and various activities based on real-life math education. Thus, it is necessary to consider this situation in pre-service teacher's education. The purpose of this study is to apply the 'Mathematics Field Trips Activities' in the pre-mathematics teacher education. So the specific case of 'Mathematics Field Trips Activities' was analyzed. Mathematics teachers conducted preliminary exploration activities on the historical cultural property which were effective in the following four aspects. First, cognitive effects and second, definitive effect. Third, cultural-mathematical effect. Fourth, the effect on improving math class. Finally they were summarized and divided into classes target content knowledge and teaching knowledge both sides. As a result, the 'Mathematics Field Trips Activities' were found to have significant effects on pre-service math teacher. Finally, ongoing research is needed to settle into a new teaching and learning methods.

• Journal of Korean Association for Spatial Structures
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• v.20 no.2
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• pp.51-58
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• 2020

Recently, deep learning that is the most popular and effective class of machine learning algorithms is widely applied to various industrial areas. A number of research on various topics about structural engineering was performed by using artificial neural networks, such as structural design optimization, vibration control and system identification etc. When nonlinear semi-active structural control devices are applied to building structure, a lot of computational effort is required to predict dynamic structural responses of finite element method (FEM) model for development of control algorithm. To solve this problem, an artificial neural network model was developed in this study. Among various deep learning algorithms, a recurrent neural network (RNN) was used to make the time history response prediction model. An RNN can retain state from one iteration to the next by using its own output as input for the next step. An eleven-story building structure with semi-active tuned mass damper (TMD) was used as an example structure. The semi-active TMD was composed of magnetorheological damper. Five historical earthquakes and five artificial ground motions were used as ground excitations for training of an RNN model. Another artificial ground motion that was not used for training was used for verification of the developed RNN model. Parametric studies on various hyper-parameters including number of hidden layers, sequence length, number of LSTM cells, etc. After appropriate training iteration of the RNN model with proper hyper-parameters, the RNN model for prediction of seismic responses of the building structure with semi-active TMD was developed. The developed RNN model can effectively provide very accurate seismic responses compared to the FEM model.

• Korean journal of communication and information
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• v.68
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• pp.34-64
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• 2014

This paper analyzed the modes of human communication of the Korean enlightenment era through 9 new-style novels with the assumption that the fictitious world of novels reflect the social realities of that time. The most noticeable fact was that the communication environment of that time were remarkably diversified with the new media, such as newspaper, printed book, postal system, telegraph, telephone, and photo. But the communication of most people was mainly relied on traditional oral communication. In oral communication the hierarchical relationship and age were the most important variable as usual but the formality and etiquette were weakened than Late Chosun Dynasty. The distribution of written culture was enlarged especially by women and lower class. The contact with the foreign cultures which had become possible after the opening of ports brought about intercultural communication. In conclusion it can be said that the communication of people in the enlightenment era was mainly by oral communication but the reliance on the media was enlarged gradually.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.41.4-42
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• 2015

Outflows and jets from young stellar objects (YSOs) are prominent observational phenomena in star formation process. Indicating currently ongoing star formation and directly tracing mass accretion, they provide clues about the accretion processes and accretion history of YSOs. While outflows of low-mass YSOs are commonly observed and well studied, such studies for high-mass YSOs have been so far rather limited owing to their large distances and high visual extinction. Recently, we have found a number of molecular hydrogen (H2 1-0 S(1) at 2.12 micron) outflows in the long, filamentary infrared dark cloud (IRDC) G53.2 located at 1.7 kpc from UWISH2, the unbiased, narrow-band imaging survey centered at 2.12 micron using WFCAM/UKIRT. In IRDC G53.2 which is an active star-forming region with ~300 YSOs, H2 outflows are ubiquitously distributed around YSOs along dark filaments. In this study, we present the most prominent H2 outflow among them identified in one of the IRDC cores MSXDC G53.11+00.05. The outflow shows a remarkable bipolar morphology and has complex structures with several flows and knots. The outflow size of ~1 pc and H2 luminosity about ~1.2 Lsol as well as spectral energy distributions of the Class I YSOs at the center suggest that the outflow is likely associated with a high-mass YSO. We report the physical properties of H2 outflow and characteristics of central YSOs that show variability between several years using the H2 and [Fe II] images obtained from UWISH2, UWIFE and Subaru/IRCS+AO188 observations. Based on the results, we discuss the possible origin of the outflow and accretion processes in terms of massive star formation occurring in IRDC core.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.82.1-82.1
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• 2013

The SPICA (SPace Infrared Telescope for Cosmology & Astrophysics) project is a next-generation infrared space telescope optimized for mid- and far-infrared observation with a cryogenically cooled 3m-class telescope. Owing to unprecedented sensitivity and high spatial resolution, the focal plane instruments are expected to perform the confusion-limited observation. The SPICA will challenge to reveal many astronomical key issues from the star-formation history of the universe to the planetary formation. The Korean 5contribution to SPICA as an international collaboration is the development of the near-infrared instrument, FPC (Focal Plane Camera). The Korean consortium for FPC proposed a key system instrument for the purpose of a fine guiding (FPC-G) complementing the AOCS (Attitude and Orbit Control System). The back-up instrument of FPC-G, FPC-S will be responsible for the scientific observations as well. Through the international review process, we have revised the scientific programs and made the feasibility study for the fine guiding system. Here, we report the current status of SPICA/FPC project.

• Journal of the Korean Society of Costume
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• v.52 no.5
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• pp.173-186
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• 2002

Street Style, occurred in British and America, has been expressed the character of the new generation by repeating developments and changes. Nowadays, pop music reflects the phase of society. and simultaneously it has influence on from culture to society. Rock Music was rooted in Country 8l western of America. Upon Country & Western, Afro-Americans Rhythm & Blues was added, and that was the birth of Rockabilly. Rockabilly developed to Rock'n 'roll and it started to change to various forms of Rock since 1950s. As the commercial impact and the breakthrough of teenagers emotion, the rock culture comprised the base of the youth culture. However. it formed the anti-establishment culture against the established value, accepting working class subculture. The teenager culture was affected by the Rock culture, also found relief in the opulence provided by the established generation, imitating it as it was. Simultaneously, it had a contrary aspect as anti-establishment form under the banner of revolt against languor in richness. The youth culture created street style that was escaped from high fashion, every time Rock music had changes. Since Street style was based on resistance of established culture and it fully refused vogue, it was indifferent from high fashion. The results of this study were as following. First, every time Rock music had changes, the new youth culture was concomitant with, the youth culture created street style. Secondly, rockahibilly style was characterized as diamond shaped design, embroidery, extra wide shirt collar, vivid contrast color . Rockers style was represented as metal studs, beads, denim, leather jacket, boots. Fusion of hippies style and Psychedelic, long hair, beads. worn denim were elements of headbangers style. Punks style was characterized as ripped T-shirt. rooster hair, over decorated jacket, short skirt. net or plastic T-shirt. Lastly, the firm relation between popular art and fashion was proved by examining the history of Rock Music and Street Style.

• Journal of the Korean Society of Costume
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• v.64 no.1
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• pp.152-164
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• 2014

Korean people have revered the white color and enjoyed wearing white clothes. Various kinds of white clothes have been worn by the Korean people, ranging from everyday wear(便服), and scholar's robe(深衣) for the upper class, to religious costumes like Buddhist monk's robe(僧服), shaman costumes(巫服) and costumes for ancestral rites(祭服), or mourning(喪服). There have been many differing opinions by historians regarding the background of this Baekeuihosang(白衣好尙, the preference for white clothing) tradition and even now, it is frequently being discussed. This study aims to consider and discuss the background of this Baekeuihosang tradition, focusing on Chang-seon Yoo's Baekeuigo(白衣考, the consideration of white clothing), which was published in Dong-A Ilbo in 1934. The purposes of studying literature such as the Baekeuigo is to analyze the arguments on the origin of Baekeuihosang, to analyze Chang-seon Yoo's claim of its origin, and to discuss the culture of Baekeuihosang. Chang-seon Yoo claimed that the existing discussions on the background of Baekeuihosang based on the lack of dyes, or undeveloped technique, economic privation and national control strayed from historical facts, according to literature review. It is not worth discussing the farfetched arguments such as the use of costumes for ancestral rites as everyday wears, or the nation of sorrow. Baekeuihosang tradition mostly originated from the effects of many religions and the taste for innocence, or naturalness. White clothes were infused with the sorrow and emotion of Korean people and were also worn to show resistance to foreign power as symbols of ethnicity. Therefore, there should be a new view of the discussion of white clothes and Korean aesthetic sense, away from the logic distorted by the Japanese colonial view of history.