• The korean journal of orthodontics
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• v.29 no.4 s.75
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• pp.445-456
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• 1999

As a result of increased education and communication, the field of orthodontics has recently been expanded to include a greater number of adult treatment procedures. With this increased demand for adult orthodontic treatment, a problem that frequently arises is the placement of appliances on teeth restored with porcelain. But conventional acid-etching is ineffective in the preparation of porcelain surface for mechanical retention of orthodontic attachments. Also, it is possible to damage on porcelain. The purpose of this study was to evaluate the effect of composite bonding materials and the porcelain surface treatment methods on shear bond strength, and to observe the porcelain fracture rates. To accomplish this purpose, this study was carried out with feldsphatic porcelain, Ceram II. Porcelain surface treatment methods were divided into intact glazed porcelain which had not treatment and surface roughening. Surface roughening by etching with Hydroluoric acid(HF), sandblasting with Microetcher II and compound treatment with etching and sandblasting. Bonding materials were Ortho-two and Transbond. All porcelain specimens were applicated with porcelain primer. 1. In comparision according to porcelain surface treatment, surface roughening groups by HF etching and sandblasting had higher shear bond than intact group. No significant difference was found in Transbond group. 2. Ortho-two group had the higher shear bond strength than that of Transbond group in B:.u etching and sandblasting. 3. E(Transbond. Intact)group had the lowest shear bond strength in all experimental group. The bond strength was higher than clinically successful bond strength. 4. Non-treated group had very higher porcelain rates than treated group. 5. This study indicates that porcelain surface-roughening may not be necessary to attachment of orthodontic brackets to porcelain surfaces.

• Journal of Korean Home Economics Education Association
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• v.21 no.2
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• pp.83-107
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• 2009

The purpose in this study was to provide a basic resource for enhancing teachers' professional competence by examining how the Home Economics(HE) teachers had formed, developed, and introspected the pedagogical content knowledge in the HE classes of secondary schools. Data were collected through in-depth interviews with six HE teachers working at secondary schools. NVivo program, a kind of CAQDAS was used to analyze the data inductively. This study revealed that the HE teachers reflectively introspected the pedagogical content knowledge in Home Economics Education(H-PCK) as follows: First, as for knowledge of perspective on Home Economics Education(HEE), the research participants encouraged students to solve practical problems regarding the objective of HEE. They tried to foster the students' critical thinking ability related to the daily life. They made eager efforts to achieve the mission of HEE as a practical science. Second, as for knowledge of HE curriculum, the research participants mentioned that there was lack of systematic approach concerned with curriculum development. While reorganizing, they always paid attention to its relation to the students' daily lives, to the relationship between the curriculum contents and the social context. Third, as for knowledge of teaching strategies on practical problem-based instruction, the research participants developed the practical problem-based instruction skills. They mentioned students' difficulties in relating the practical problem-based instruction, too. Fourth, regarding knowledge of context, as teachers mostly prepared for progressed instruction alone without communicating with colleagues in the same school, they yearned for and also formed networks with other HE teachers in order to overcome their limitations.

• The Korean Journal of Air & Space Law and Policy
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• v.8
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• pp.231-248
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• 1996

이 논문(論文)은 한국(韓國)의 우주(宇宙) 산업(産業) 발달(發達)과 그 과정(過程)을 고찰(考察)하고 현재 진행 중인 통신위성(通信衛星)의 개발(開發)과 그 사업(事業)을 뒷받침해 주는 국가(國家)의 정책(政策)을 살펴보고 있다. KOREASAT라고 명명(命名)된 통신위성(通信衛星) 개발(開發)에 현재 여러 기관이 관계(關係)하고 있으나 그 중 KARI(한국항공우주연구소(韓國航空宇宙硏究所)), ETRI(전자통신연구소(電子通信硏究所)), SERI(시스템공학연구소(硏究所)), KAIST(한국과학기술연구소(韓國科學技術硏究所)) 등이 중추적인 연구(硏究)를 하고 있다. 특히 이 논문(論文)에서는 아래와 같은 문제(問題)를 다루고 있다 첫째, 최근(最近) 한국우주개발(韓國宇宙開發) 상황(狀況) 둘째, 장기(長期) 우주개발(宇宙開發) 계획(計劃) 셋째, 현재(現在) 우주개발(宇宙開發) 상황(狀況)과 미래(未來) 우주개발(宇宙開發)에 관련한 정책(政策)적 문제(問題) 넷째, 한국(韓國) 우주개발(宇宙開發)과 정책(政策) 방향(方向)에 대한 의견(意見) 최근의 한국우주개발(韓國宇宙開發) 상황(狀況)은 크게 한국(韓國)의 통신위성(通信衛星) 사업(事業)인 Koreasat program과 다목적 위성사업(衛星事業)인 KOMSAT로 나타나는데 한국(韓國)의 최초 상업용(商業用) 위성(衛星)인 Koreasat는 1호가 1995년도에 발사(發射)되었으나 정상궤도(正常軌道) 진입(進入)에 문제(問題)가 발생하여 발사업체(發射業體)로부터 보상문제(補償問題)가 제기(提起)되기도 하였으나 2호는 성공리에 발사(發射)되었다. 미국항공우주회사(美國航空宇宙會社)와 공동(共同)으로 개발(開發)중인 새로운 과학위성(科學衛星)인 KOMSAT는 한국우주과학기술(韓國宇宙科學技術)을 한단계 더 발전(發展)시킬 수 있을 것이고 1999년도에 발사(發射) 계획(計劃)이다. 한국항공우주연구소(韓國航空宇宙硏究所) 중심(中心)의 장기(長期) 우주개발(宇宙開發) 계획(計劃)에서 제시(提示)하는 4가지 우주개발(宇宙開發)의 기본목표(基本目標)는 첫째, 우주산업응용산업(宇宙産業應用産業)의 상호협조개발(相互協助開發)에 의한 우주산업(宇宙産業) 육성(育成) 둘째, 한국(韓國)의 현재 우주산업상황(宇宙産業狀況)에 알맞은 특정분야(特定分野)를 선정(選定)하고 이 분야(分野)에서 최단기에 세계(世界) 최고의 기술수준을 성취(成就)하도록 집중(集中) 셋째, 외국과 긴밀한 협조(協助)로 선진기술(先進技術)의 습득(習得) 넷째, 체계적이고 통합(統合)된 장기우주산업발전(長期宇宙産業發展) 계획(計劃) 성립(成立) 등이다. 이러한 계획(計劃)에 주요 사안(事案)으로는 2015년까지 19기의 인공위성(人工衛星) 보유(保有)를 위한 제작계획(製作計劃)과 2010년까지 발사체(發射體) 개발(開發)을 마련하는 것이다 현재 우주활동(宇宙活動)에 관련된 문제(問題)는 주로 Koreasat의 서비스와 사용계획(使用計劃)에 대한 것으로 위성개발사업(衛星開發事業)에 있어서 관련 정부부서간(政府部署間)에 의견(意見)을 달리하고 있는 형태이다. 한국통신(韓國通信)과 정보통신부(情報通信部)는 위성(衛星)의 DBS 트랜스폰더에 대해 디지털 방식(方式)을 적용(適用)할 것을 제안(提案)했지만 공보처(共報處)는 반대(反對)의 입장(立場)을 표명(表明)한 것과 방송국(放送局)의 관리(管理)와 통제(統制)는 공보처(共報處)에 있고 무선통신표준(無線通信標準)에 대한 면허(免許)는 정보통신부(情報通信部)에 있기 때문에 방송국(放送局)에 대한 면허(免許)는 각기 다른 두 단계(段階)로 구성(構成)되는 문제(問題)가 발생(發生)한다. 또한 DBS 서비스에서 사기업(私企業)의 참여(參與)와 관련하여 재벌(財閥)의 참여(參與)를 허용(許容)하느냐의 여부(與否)의 논쟁(論爭)이다. 다음으로 미래(未來) 우주산업개발(宇宙産業開發)에 관한 정책문제(政策問題)를 살펴보면 국가적(國家的) 차원(次元)에서 조직적(組織的)인 육성책(育成策)에 대한 문제(問題)로 현재 주관 부처가 과학기술처(科學技術處)와 통상산업부(通商産業部)로 나뉘어 추진(推進)되고 있다는 점이다. 그리고 차세대(次世代) 통신위성개발(通信衛星開發) 계획(計劃)에 대한 문제(問題)로 최소 2${\sim}$4개의 궤도확보(軌道確保)와 이미 정상궤도(正常軌道) 진입(進入) 실패(失敗)에 따른 Koreasat 1호의 생명단축(生命短縮)으로 새로운 통신위성(通信衛星)을 4년이내에 발사(發射)해야 한다는 문제(問題)이다. 결론적으로 장기(長期) 우주개발계획정책(宇宙開發計劃政策)에 있어서 첫째, 국제적 우주개발사업(宇宙開發事業)에 대한 적극적(積極的) 참여(參與), 둘째, 우주(宇宙)에서 독립적(獨立的)인 활동(活動)을 할 수 있는 국가안보체제(國家安保體制)의 개발(開發), 셋째, 국가(國家) 위상(位相)의 발전(發展)과 우주개발(宇宙開發)을 위한 인력활용(人力活用)의 개발(開發), 넷째, 무한한 우주(宇宙)에 도전(挑戰)할 수 있는 우수(優秀)한 인재(人才)의 교육(敎育), 다섯째, 21세기를 대비(對備)하여 한국(韓國)의 우주개발정책(宇宙開發政策)의 결정(決定) 등이 고려(考慮)되어야 할 5가지 요소(要所)들이다. 그리고 막대(莫大)한 비용(費用)이 드는 우주개발사업(宇宙開發事業)을 효율적으로 추진(推進)하기 위해서는 국가(國家) 최고(最高) 지도자(指導者)의 직접지휘(直接指揮)를 받는 정부기구(政府機構)가 수립(樹立)되어 정부차원(政府次元)에서 추진(推進)하되 산학연(産學硏)이 협조(協助)하여 우주개발계획(宇宙開發計劃)을 추진(推進)하여야 할 것으로 본다.

• Journal of the Korea Convergence Society
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• v.1 no.1
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• pp.41-47
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• 2010

This study was conducted to investigate determinent factors of the internet addiction that have influenced on middle school students. We randomly selected each one middle school in urban and rural areas, and conducted survey in 862 students of 2nd and 3rd grade from September 1 to 15, 2005. By using a statistical program called SPSS10.0, the data collected thereby were analyzed through a series of statistical methods including $x^2$-test, logistic regression analysis. The result of logistic regression analysis showed that the significant variables in urban area were resting time and using time a day. In rural area, sex, economic level, resting time and using time a day were significant variables. Higher status of internet addiction showed significant relationship with physical problems, anxiety, maladjustment to school, insufficient sleep time, fatigue in eyes, headache, pain in neck or shoulder, chronic fatigue, reduced vision, weight reduction, indigestion, xeroderma and adjustment to school. Especially, resting time and using time a day have dominant influence on internet addiction. And in case that the groups who showed high addiction tendency, there were negative health problem by physical, mental and social problem. To prevent internet addiction health education programs of right internet use and time, importance of rest, and health problems must be considered in internet addiction prevention policy.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.381-391
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• 2001

In orthodontic patients, frequently, amalgam restorations are present on the buccal surface of molars. The ability to successfully bond orthodontic brackets and buccal tubes to amalgam restorations would therefore be of clinical value. But the bond strength to total amalgam surface is probably not critical in most instances. Because there is usually a considerable amount of sound enamel surrounding a buccal amalgam filling. The purpose of this study was to evaluate the bond strengths of orthodontic brackets according to surface treatments and size of amalgam restorations. Eighty tooth specimen were assigned to four groups according to amalgam size-1.5mm, 2.0mm, 2.5mm, 3.0mm diameter-and then divided into two groups : one half was sandblasting group the other half was no sandblasting group. After Bracket bonding, shear bond strength for each specimen was determined and bond failure patterns was evaluated. 1. Shear bond strength of amalgam size 1.5mm group was significantly higher than that of the other groups. (p<0.05) 2. There was no significant difference in the bond strength produced by sandblasting. (p<0.05) 3. Shear bond strength of G and H group of which amalgam restoration ratio to the bracket base sizes were $61\%$ were significantly decreased $50-60\% level of that of control group. (p<0.05) 4. There was positive correlation between sandblasting and mARI. (p<0.05) The results of the present study indicate that it may be feasible to bond orthodontic bracket clinically successfully to amalgam restoration with conventional orthodontic resin when its size is less than $50\%$ of that of bracket base.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.9B
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• pp.610-618
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• 2005

As developed Internet and Computer Capability, Many Users take the many information through the network. So requirement of User that use to network was rapidly increased and become various. But it spend much time to accept user requirement on current network, so studied such as Active network for solved it. This Active node on Active network have the capability that stored and processed execution code aside from capability of forwarding packet on current network. So required execution code for executed packet arrived in active node, if execution code should not be in active node, have to take by request previous Action node and Code Server to it. But if this execution code take from previous active node and Code Server, bring to time delay by transport execution code and increased traffic of network and execution time. So, As used execution code stored in cache on active node, it need to increase execution time and decreased number of request. So, our paper suggest ANC caching technique that able to decrease number of execution code request and time of execution code by efficiently store execution code to active node. ANC caching technique may decrease the network traffic and execution time of code, to decrease request of execution code from previous active node.

• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.706-716
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• 2002

The purpose of this study was to compare and analyze the science process skills and teaching methods between the 6th and the 7th elementary school science textbooks. For this study, science textbooks and teacher's guidebooks from the 3rd to the 6th grade were analyzed. In this research the science process skills are divided by basic process skills(BPS) and integrated process skills(IPS). The BPS is composed of observing, classifying, measuring, predicting and inferring skill, which are 5 subcategories. The IPS is composed of problem cognition, formulating hypothesis, controlling variables, transforming data, interpreting data, drawing result, and generalization, which are 7 subcategories. The results found in the analysis of science process skills in the 6th and 7th science textbooks are as follows: 1. The percentage of the BPS was increased, but the IPS was decreased in the 7th than the 6th. 2. The percentage of the IPS was higher than the BPS in the 6th science textbooks, but the BPS was higher than IPS in lower grade and the IPS was higher than the BPS in higher grade in the 7th textbooks. 3. Observing and problem cognition skill were most dominant in the 6th and 7th science textbooks. 4. The percentages of observing(24.8%), classifying(5.4%), measuring(5.6%), inferring(6.0%) in the BPS and interpreting data(4.4%) in the IPS were increased, but predicting(3.8%), formulating hypothesis(0.5%), controlling variables( 1.8%), transforming data( 1.2%), drawing result(0.8%) and generalization(0.9%) skills were decreased in the 7th. And teaching methods suggested in the curriculum are as follows: the percentages of learning by observation(19.2%) and role play(0.1 %) were decreased, but learning by experiment(6.2%), learning by discussion(2.0%), learning by investigation(4.6%) and creative learning(6,4%) were increased in the 7th than the 6th. In conclusion, it was found that the basic process skills were emphasized in the 7th science textbooks than the 6th and the science process skills in the science textbooks of the 7th curriculum were distributed by the grade level of the elementary children.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.149-156
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• 2014

The resistance levels of the green peach aphid, Myzus persicae (Sulzer), against 10 insecticides was checked and selected the applicable insecticide resistance markers. We conducted our study in 5 cabbage cultivation regions (Pyeongchang, Hongcheon, Bongwha, Muju, and Jeju) of Korea, over 3 successive years (2009-2011). We selected a multi-resistant (MR) strain from among the 5 field-collected populations. We analyzed esterase over-expression and mutation(s) in the target sites, by using native isoelectric focusing (IEF) and quantitative sequencing (QS). We detected esterase over-expression and StoF mutation in the acetylcholinesterase 1 gene (ace1) in all of the field-collected populations, including the MR strain. We did not detect the LtoF mutation, which is a well-known knockdown resistance (kdr) mutation in the para-type sodium channel gene (para), in the MR strain; however, the value of the MR strain for bifenthrin was 3,461-fold higher than that of the susceptible strain. Our results indicate that insecticide resistance is more effectively evaluated using molecular markers than by conducting a bioassay. The molecular markers StoF in ace1 and MtoL in para can easily be applied in diagnostic methods such as QS or PCR amplification of specific alleles (PASA). These methods may be extended to management of M. persicae resistance in the field.

• Journal of Music and Human Behavior
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• v.5 no.1
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• pp.19-45
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• 2008

The purpose of this study was to offer fundamental data to manage countertransference, and to research into countertransference management ability by aspects in therapists' experiences in countertransference and their professional characters. For the paper, a survey was conducted on 62 music therapists who provided professional music therapy after finishing graduate school of music therapy through clinical practice and internship, and the result was drawn as follows. Around 84% of participants answered that they had been in trouble by countertransference in the analysis of a questionnaire regarding experience in countertransference. 48% among them first experienced countertransference during the practice in graduate school. 27% and 14% respectively answered that they experienced it within 3 years after graduation and during internship. Also, the result showed that therapists usually had difficulty with adults with mental disease, and the second most difficult clients were children with developmental disabilities. 76% of participants who had difficulty by countertransference answered that they were able to manage it to some degree, and almost all who answered thought that research into countertransference and management were necessary. About the question as to how to manage countertransference, 54% suggested self-analysis and self-therapy. 33% answered that countertransference should be treated through supervision. Finally, 13% of participants answered that it should be handled in graduate school. In this paper, which empirically examined therapists' experience in countertransference and countertransference management ability had meaning in providing essential basic data for music therapists to apply and manage countertransference for therapists themselves, as well as for clients.

• Therapeutic Science for Rehabilitation
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• v.9 no.1
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• pp.69-78
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• 2020

Objective : The purpose of this study was to conduct a comprehensive survey of children's play in parents of disabled and non-disabled children prior to commencing school. This study aimed to further understanding play recognition and to present a specific direction of play necessary to each parent. Methods : A questionnaire based on prior studies was sent to 700 people who had previously agreed to the take part. A total of 596 questionnaires were analyzed. Uncollected and insincere surveys, of which 106 were questionnaires for parents of disabled children, were exclused from analysis. The SPSS Window 23 program was used for data analysis and frequency analysis and the independent sample T test were performed. Results : Disabled children's parents perceived playing with their children as more important than that of non-disabled children's parents(p<0.01). There was no statistical difference between disabled children and non-disabled children's parents, but there were some differences(p=0,053). Both disabled and non-disabled children had more time to participate with their mothers than with their fathers. Mothers with disabilities had more time to play however, fathers with no disabilities had more time. Both disabled and non-disabled children's parents had the most "ordinary" frequency of buying toys and there was very littele difference between the 2 groups. Both disabled and non-disabled children's parents primarily used the internet to acquire play information, and consideration when buying fun was followed by interest inducement, development level and safety. Conclusion : Through this study, it was possible to compare the status of play recognition and participation by parents of children with or without disabilities. Based on this study, parents will be able to find out what they really need to play and will be provided as a basis for future play studies for children.