• Journal of Conservation Science
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• v.27 no.2
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• pp.135-144
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• 2011

When metal artifacts have to undergo conservation treatment, the person in charge of the treatment selects and uses various coating mixtures based on his judgment regarding their condition, material, or environment. Since the kinds of coating mixtures or solvents make a difference in the set time of cyanoacrylate adhesives, they have something to do with the efficiency of the conservation treatment. This study examines the effects and causes that affect the set time of cyanoacrylate adhesives according to the kinds of coating mixtures and solvents and suggests ways to increase the set time. As a result, it is thought that as the surface roughness gets flatter, the wettability of adhesive is improved further, which increases the set time. Moreover, the C-F binding of V-Flon, C-O-C absorption peak, molecular weight of the coating mixtures, and glass transition temperature (Tg) were the factors that significantly affected the set time. According to the result of measuring the set time based on the result of superficial and chemical analysis, relative difference was shown according to the kind and viscosity of adhesive, but all the adhesives indicated the following order of the set time: V-Flon > Paraloid B-72 (in xylene) > Paraloid NAD-10 > Paraloid B-72 (in acetone).

• Journal of Korean Society of Steel Construction
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• v.27 no.1
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• pp.23-30
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• 2015

Developed in this study were Octagonal-hollow-section(OHS) struts, whose compressive strengths against flexural and local buckling is higher than H-shape or rectangular-hollow-section(RHS) struts with the same unit weight. OHS members are also advantageous in handling and storing compared to circular hollow sections(CHS). OHS members were fabricated from HR Plates by cold forming and fillet welding. 5 numbers of 20m long OHS struts were assembled, each of which consist of two 9.6m long OHS member and two end connection elements made of cast iron. The compressive strength of the OHS strut was evaluated by comparing the test results, design codes and FEM analysis each other. Test results show that all of the struts have almost same or larger compressive strength than Korean Road Bridge Design Code(KRBDC) (2012). The initial imperfections can be estimated by using measured strains and are turned out to be less than L/450 for all the struts tested. The results of FEM analysis show that the variation of initial imperfection has less effects on the compressive strength for struts with vertical surcharge than for those with self-weight only, while the strength decreases as the initial imperfection increases. As the result of this study, the allowable initial imperfection for 20m long OHS struts is recommended to be less than L/350 on job sites.

• Journal of the Korean Home Economics Association
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• v.43 no.5 s.207
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• pp.131-147
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• 2005

The purpose of this study was to provide a better understanding of foreign-born Korean children's early school adjustment in the U.S. The interaction between the foreign-born Korean children in the U.S. and several of the children's microsystems, including family, school, and peer was assessed to meet this purpose. The study subjects were 43 foreign-bom Korean children who were sampled from Korean Sunday Language schools and who attended local schools in the Boston area, MA, USA. Quantitative analysis was conducted to identify which variables of interest predicted the early adjustment of this group of children. Furthermore, in-depth interviews were conducted with mothers of the children from the top and bottom groups 1) the most successful (in the top quartile) and 2) the least successful adjustment groups (in the bottom quartile) sorted by scores on the Peabody Picture Vocabulary Test-Revised (PPVT-R). The interview results were analyzed to elicit maternal perceptions/beliefs on education, in general, and those of home-school relationships, in specific. Several conclusions can be drawn from both the quantitative and qualitative analyses. The results of multiple regression and path analysis showed that the children's language development predicted their adjustment, but the effects of the other two variables, peer relationships and school experiences, on the adjustment of children, were mediated through the children's language. Moreover, common themes and patterns in the responses to a series of open-ended questions emerged from the interviews with the two groups of mothers. The two mothers of the least successful group were concerned about their children's future and school success, but thev did not show anv responsive attitudes toward achieving this goal. By contrast, the mothers from the most successful group were self-determined with regard to their children's education and had strong beliefs and values on how to raise their children in the new culture. The implications were discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.945-952
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• 2018

Recently, bass fishing has become a marine leisure sport in Korea. There are 4 major fishing associations in Korea, and each association holds 10-15 tournaments each year. However, supply of 17 ft bass boats, which are preferred in leagues, depends 100 % on imports. In this study, we have derived the main specifications to develop the initial hull forms of a 18.5ft bass boat through statistical analysis based on mothership data. In addition, CFD numerical analysis was carried out according to deadrise angle and longitudinal center of gravity, which strongly influenced the resistance and planing performance. For numerical analysis, design speed was set to $Fn=3.284 (Re=9.858{\times}10^7)$, the deadrise angle was set from 12 to $20^{\circ}$, and the longitudinal center of gravity was set in the range of 0 to $8%L_{wL}$ from the center of buoyancy to the stern. Based on the numerical results, we first set the range of these factors by resistance performance and immersion keel length. Furthermore, using a correlation graph of Savitsky's Drag-Lift ratio, we derived the deadrise angle ($14-16^{\circ}$) and longitudinal center of gravity ($4-6%L_{wL}$).

• Journal of the Korean association of regional geographers
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• v.8 no.3
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• pp.347-363
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• 2002

The purpose of this study is to analyse the formation process and spatial structure of the mountainous village in the historic process as the case study on Yowon-village, Gyeongbuk province. The findings are summarized as the follows. The traditional location of the Yowon mountain village has been strongly influenced by local topology, drinking water, the form and time of the early setters. The spatial structure of the village was changed by the construction of road and accessibility to the road after the introduction of commercial agriculture. The form of the village consists of small scale of concentrated villages and dispersed. villages. Specifically, Yowon 1 ri has been restructured as a small scale of concentrated village and Yowon 2 ri as a dispersed one. The facilities both located in the center of the traditional village and related to communal life were moved outside while those for commercial agriculture were located in the center of the village. In sum, the village had been traditionally life-oriented and closed, but it was production-oriented and open particularly after the introduction of commercial agriculture.

• Review of KIISC
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• v.13 no.6
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• pp.37-54
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• 2003

안전한 정보시스템 사용 환경 구축을 위하여 미국이 TCSEC을 개발한 이래 국가별로 자체 정보보호시스템 평가기준을 제정하여 사용하였다. 유럽에서는 영국, 독일, 프랑스가 중심이 되어 ITSEC을 개발하였으며, 이후 미국, 캐나다 및 유럽 4개국이 공동으로 모든 IT 보안성 평가에 적용할 수 있도록 CC를 개발하였다. 대부분의 국가는 초기에 정부 기관에 의해 평가가 이루어졌으나 평가수요 확대 및 시장성장 등에 따라 민간 평가기관을 지정하여 운영하고 있다. 본 고에서는 국외 민간평가기관에 의한 평가 현황을 분석하여 평가 동향 및 향후 전망을 살펴본다.

• Defense and Technology
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• no.3 s.133
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• pp.20-33
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• 1990

우리나라 조병기술 발전의 자취를 살펴, 미래상 정립에 일조를 함은 물론 관계인사 미 독자 여러분께 좋은 자료로서 제공하고저, 본 지 창간 11주년기념 특집시리즈로서 꾸며 보았습니다. 이 글은 총 3편으로 구성되며, 조선시대부터 1980년까지를 대상으로 하였습니다. 지난 '90년 1월호(통원 제131호)에서는 조선시대부터 창군초기까지를 살펴보았으며, 이번 호는 휴전이후인 1954년에서 ADD 창설이전까지를 위주로 다루었습니다. 다음 호에서는 국방과학연구소(ADD)의 설립배경과 초창기 연구개발 활동을 중심으로 꾸며볼 계획입니다

• The monthly packaging world
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• s.253
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• pp.104-108
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• 2014

일본에서 포장기계의 시작은 주로 종전 후의 시기로, 사탕이나 비누의 포장 등의 자동화에서부터 시작됐다. 국산 기술에 의한 개발도 다수 있었지만, 식품의 서양화, 슈퍼마켓의 발달 등 서양에서부터의 도입과 관련해 초기의 포장기계는 유럽과 미국에서부터의 수입, 기술 제휴, 또는 어느 기종을 모티브로 한 국산화 등에 의한 보급이 중심이 되었다. 본 고에서는 당시 일본시장에 존재하지 않았던 포장기계(시스템)를 시장 조사, 기술 제휴, 또는 수입 판매로 일본 시장에 도입하고, 그 후 어려운 보급 기간을 거쳐 약 40년 후인 현재 대표적인 포장기계로 확립된 포장기계 3종류를 소개하고자 한다.

• 정보화사회
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• s.177
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• pp.36-37
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• 2005

"항상 어려웠던 시절을 잃지 않는 초심경영과 신규아이템 개발에 적극 투자한 것이 지금의 이레전자를 있게 한 원동력입니다" 설립 15주년을 맞은 이레전자산업 정문식 사장(43)의 말이다. 이 회사는 1990냔 창업초기 무선전화기 및 휴대폰 충전기 사업을 거쳐 지난 2000년 사업다각화의 하나로 CDMA단말기 생산 및 디지털 디스플레이 사업분야를 중심으로 집중적인 마케팅을 펼치고 있다. 특히 2000년 LCD모니터, 2002년 PDP 그리고 2003년에는 LCD TV시장에 진입하며 세계 디스플레이 시장을 적극공략, 현재는 DTV 중소업계의 선두 위치에서 매출 2000억원 대를 바라보고 있다.

• Electronics and Telecommunications Trends
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• v.28 no.2
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• pp.70-76
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• 2013

인체통신 기술은 유선통신 기술에서와 같이 기기들 간의 연결을 위한 다양한 형태의 케이블이 필요하지 않으므로 기존 유선통신 기술에 비해 편리한 우월성을 가진다. 그렇지만 보안성과 신뢰성은 유선통신의 장점을 넘을 수는 없을 것이다. 무선통신 기술은 초기 네트워크를 구성하기 위하여 서로 복잡하게 주고 받는 절차단계가 필요한 반면, 인체통신 기술은 사용자의 간단한 접촉만으로 통신이 서로 이루어지기 때문에 보다 더 간편하게 연결되며, 사용자 중심의 서비스를 용이하게 제공할 수 있다. 본고는 최근의 인체통신 기술의 기술 동향과 시장 전망 및 표준화 동향을 살펴보고자 한다.