• Title/Summary/Keyword: 문헌 의존도

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Constituents of Collagen Synthesis Activation from the Extracts of Gynostemma pentaphyllum Leaves (돌외 잎 추출물의 콜라겐 합성 증진 성분 규명)

  • Yim, Jun Hwan;Jang, Moon Sik;Jung, Uk Sun;Moon, Mi Yeon;Lee, Ha Youn;Kim, Young Hoon;Lee, Gi Yong;Lee, Nam Ho
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.40 no.3
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    • pp.289-295
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    • 2014
  • In order to discover ingredients for wrinkle-care cosmetics, we prepared 70% ethanol extract from Gynostemma pentaphyllum and examined its activity on collagen synthesis using fibroblast HDFn cells. The G. pentaphyllum extract induced the production of type I procollagen in a dose-dependent manner without showing cell toxicity. The active constituents were isolated from the extract by solvent fractionation and chromatographic purification procedures. NMR data and literature studies led to determine the two isolated compounds as the flavonoid glycosides such as ombuine 3-O-rutinoside (1) and quercetin 3-O-rutinoside (2). The activity screening tests showed that the isolates 1 and 2 induced the production of type I procollagen in a dose-dependent manner. These results suggested that G. pentaphyllum extract containing the flavonoids 1 and 2 could be useful as an active ingredient for wrinkle-care cosmetics.

Selection of extra support points for polynomial regression (다항회귀모형에서의 추가받힘점 선택)

  • Kim, Young-Il;Jang, Dae-Heung
    • Journal of the Korean Data and Information Science Society
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    • v.25 no.6
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    • pp.1491-1498
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    • 2014
  • The major criticism of optimal experimental design is that it depends heavily on the model and its accompanying assumption that often leads the number of support points equal to the number of parameters in the model. Often in the past, a polynomial model of higher degree is assumed to handle the experimental design for the polynomial regression of lower degree. In this paper we searched the possible set of designs which are robust to the departure of the assumed model. The designs are categorized with respect to D-efficiency. The approach by O'Brien (1995) was discussed in univariate polynomial regression model setting.

Information Poverty Viewed Through the Families of Children With Developmental Disabilities (발달장애아 가족의 정보빈곤 양상에 관한 연구)

  • Seo, Ok-Youn;Chang, Durk-Hyun
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.19 no.2
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    • pp.107-128
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    • 2008
  • The purpose of this study is to portray the phenomena of information poverty of the families of children with developmental disabilities. The focus was especially put on investigating their information needs of everyday lives and information-seeking behaviors. The sample group includes six children with developmental disabilities and their families, mainly mothers. The investigation was conducted by the participant observation and in-depth interviews. The study found out that they sought the formal information sources such as medical specialists and special agencies first with which they were not satisfied. As a result, they rather relied on informal information sources. And the information from 'the group of families of children with developmental disabilities' was thought to be the most reliable information for them. In terms of information related behaviors, the strongest information needs were regarding the children's special education, especially to the school education, and they made effort to seek reliable information. They, however, tended to passively treat their personal concerns that are not related to their disabled children. This study found out that their information poverty is in terms of the information environment, information sources and their attitude to information, and that it comes from the external(social) factors as well as internal(individual) ones.

Time Dependent Evaluation of Corrosion Free Life of Concrete Tunnel Structures Based on the Reliability Theory (해저 콘크리트 구조물의 신뢰성 이론에 의한 시간 의존적 내구수명 평가)

  • Pack, Seung Woo;Jung, Min Sun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.3
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    • pp.142-154
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    • 2011
  • This study predicted the probability of corrosion initiation of reinforced concrete tunnel boxes structures using the Monte Carlo Simulation. For the inner wall and outer wall in the tunnel boxes, exposed to airborne chloride ion and seawater directly respectively, statistical values of parameters like diffusion coefficient D, surface chloride content $C_s$, cover depth c, and the chloride threshold level $C_{lim}$ were examined from experiment or literature review. Their average values accounted for $3.77{\times}10^{-12}m^2/s$, 3.0% by weight of cement, 94.7mm and 45.5mm for outer wall and inner wall, respectively, and 0.69% by weight of cement for D, $C_s$, c, and $C_{lim}$, respectively. With these parametric values, the distribution of chloride contents at rebar with time and the probability of corrosion initiation of the tunnel boxes, inner wall and outer wall, was examined by considering time dependency of chloride transport. From the examination, the histogram of chloride contents at rebar is closer to a gamma distribution, and the mean value increases with time, while the coefficient of variance decreases with time. It was found that the probability of corrosion initiation and the time to corrosion were dependent on the time dependency of chloride transport. Time independent model predicted time to corrosion initiation of inner wall and outer wall as 8 and 12 years, respectively, while 178 and 283 years of time to corrosion was calculated by time dependent model for inner wall and outer wall, respectively. For time independent model, the probability of corrosion at 100 years of exposure for inner wall and outer wall was ranged 59.5 and 95.5%, respectively, while time dependent model indicated 2.9 and 0.2% of the probability corrosion, respectively. Finally, impact of $C_{lim}$, including values specified in current codes, on the probability of corrosion initiation and corrosion free life is discussed.

Current Situation and Future Tasks for Collection Development in Public Libraries: With a Special Reference to Policy Issues (공공도서관 장서개발의 현황과 과제 - 정책적 이슈를 중심으로 -)

  • Kang, Eun-Yeong
    • Journal of the Korean Society for Library and Information Science
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    • v.48 no.3
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    • pp.27-53
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    • 2014
  • It is often said that collections of public library are too poor to meet user demands in terms of quantity as well as quality. It is also criticized that this situation is related to the lack of material budget and non-systematic purchasing process. Situated in such context, this study attempted to investigate current policies and regulations that control the material budget allocation and purchasing process in public libraries, because book purchasing process in public libraries is especially influenced by policies and regulations both in national and regional levels. Policies and regulations affecting material budget allocation and purchasing process were analyzed into 4 elements, namely about (1) financial foundation supporting collection development and material budget allocation, (2) the formation of material budget and discount rates, (3) prescribing characteristics of monographs public libraries purchase, and (4) acquisition process.

A Study on Fire and Explosion Characteristics of Propane Gas (프로판가스의 화재 및 폭발 특성치에 관한 연구)

  • Ha Dong-Myeong
    • Journal of the Korean Institute of Gas
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    • v.10 no.2 s.31
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    • pp.33-39
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    • 2006
  • For the safety design and operation of many gas process, it is necessary to know certain explosion limit, flash point, auto ignition temperature and minimum oxygen concentration of handling substances. Also it is necessary to know explosion limit at high temperature and pressure. For the safe handling of propane, explosion limit and autoignition temperature of combustion characteristics for propane were investigated. By using the literatures data, the lower and upper explosion limits of propane recommended 2.0 vol% and 10.0 vol%, respectively. Also autoignition temperatures of propane with ignition sources recommended $450^{\circ}C$ at the electrically heated cruicible fumace(the whole surface heating) and recommended about $960^{\circ}C$ at the local hot surface. The new equations for predicting the temperature and the pressure dependence of the explosion limits of propane are proposed. The values calculated by the proposed equations were a good agreement with the literature data.

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A literature review on clinical/ laboratory misfit evaluation on implant-prosthesis (임플란트와 상부보철물의 임상적/실험적 부적합 평가에 관한 문헌고찰)

  • Kim, Jong-Hoi;Cho, Woong-Rae;Ko, Kyung-Ho;Huh, Yoon-Hyuk;Park, Chan-Jin;Cho, Lee-Ra
    • The Journal of the Korean dental association
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    • v.56 no.9
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    • pp.462-478
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    • 2018
  • The presence of implant-prosthesis misfits can cause various complications. It is very important to detect misfits to prevent such complications. There are various evaluation methods for misfit assessment including clinical methods and laboratory in vitro methods. The clinical misfit evaluation includes radiographic analysis, visual observation, probing, Sheffield test, evaluation with disclosing materials, and screw resistance test. The laboratory in vitro evaluation method includes indirect modelling evaluation and direct metrological visualization. Of the indirect modelling methods, photoelastic stress analysis, finite element analysis, strain gauge analysis, and microbial colonization analysis were reviewed. Of the direct metrological visualization, microscopic analysis, 3-D photogrammetric analysis, coordinate measuring analysis, and radiographic analysis were reviewed. In this review, the characteristics, advantages and disadvantages of each method were evaluated.

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A Study on the Model of School Digital Library Based Differentiated School′s Sizes (학교도서관 디지털자료실의 규모별 모형에 관한 연구)

  • Lee, Byeong-Ki
    • Journal of the Korean Society for Library and Information Science
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    • v.36 no.4
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    • pp.49-67
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    • 2002
  • School libraries are one of the essential parts for high quality education. The Seventh Educational Cumiculum emphasizes the development of creative and autonomous students who can solve problems in a self-directed way. The Ministry of Education and Human Resources Development come into forcing the installation of school digital library since 2001. Also, the Ministry of Education and Human Resources Development has presented the Master Plan of School's Activation in July 2002. In this situation, the research and discussion on effective model of school digital library are very important. Thus, This study aims to design a model of school digital library differentiated School's sizes depending on primary and secondary school's current status. This study is proposed 4 facility model of school digital library based differentiated school's sizes and designed A-type, B-Type model on individual model.

Study on Ways of Overcoming Obstacles of University-Industry Collaboration in Terms of POB(Positive Organization Behavior) (산학협력의 장애요인 및 극복방안에 관한 연구: POB(Positive Organization Behavior) 관점에서)

  • Hong, Eun Young;Choi, Jong In
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.5
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    • pp.185-196
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    • 2015
  • In a study of the existing Collaboration, U-I Collaboration linkage(LINK) has a width of the various channels through continuous mutual cooperation by the path-dependency. U-I Collaboration linkage(LINK) through the various channels is more powerful, whereas this increase trade-related barriers. In other words, It has been discussed in many literatures about the U-I Collaboration linkage(LINK). However, relatively a study on the factor of the barrier about U-I Collaboration linkage(LINK) is a minority. Given the importance of policies to establish an association of industry-university cooperation and support system, the lack of research on the obstacles to U-I Collaboration linkage(LINK) will be a serious obstacle for designing effective policies. This paper examines the existing literature about the width of mutual cooperation and the barrier of U-I Collaboration, analyze to lower the barrier of U-I cooperation through POB(Positive Organization Behavior) of university administration. In conclusion, we would like to suggest the policy implications.

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가축(家畜 Domestic Animal)들의 의사전달(意思傳達 Communication) 행동(1)

  • 김진석
    • Journal of the korean veterinary medical association
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    • v.34 no.10
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    • pp.715-725
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    • 1998
  • 우리 사람들은 자신의 생각을 다른 사람들에게 전하고자 할 때 언어를 주로 이용하고 보조적인 수단으로 몸짓을 한다. 사용하는 언어가 달라 소통이 어려울 때는 부득이 몸짓으로만 서로 의견을 나누게 되는데 손짓과 발짓은 물론 얼굴의 표정까지 동원된다. 물론 언어를 이용한 의사전달 만큼 정확하지도 못하고 시간적으로도 효율적이지 못하지만 그런 대로 급한 문제는 해결할 수 있는 경우가 않다. 동물들이 서로의 의사소통을 위하여 어떤 형태의 언어 및 언어에 가까운 음성기호를 이용할 능력이 있는지에 대하여는 학자들 간에도 논란이 계속되고 있으나 분명한 것은 어떤 방법으로든 동물들도 제나름대로 자신의 의사를 전달하고 또한 상대편이 전하고자 하는 뜻을 파악하여 이에 적절히 대처를 한다는 점이다. 이런 점에서 동물들을 대상으로 하는 학문인 수의분야에서는 우리 인간들에게 익숙한 언어와 행동이 아닌 동물들의 독특한 의사전달 방법을 정확히 이해하는 것이 무엇보다도 중요하다는 점을 인식하는 것이 필요하다 동물의 행동 하나 하나는 인간의 행동과 마찬가지로 나름대로의 의미를 지니고 있다. 이러한 동물의 행동을 인간의 눈 높이에서가 아닌 동물이 표현하고자 하는 행동 언어적인 측면에서의 이해가 필요한 것이다. 야생동물의 행동양식에 대한 연구는 생래학적으로 비교적 많이 이루어진 편이나 가축화된 동물들에 대하여는 체계적이고 비교학적인 연구가 아직도 부족한 실정이다. 특히 우리 나라에서는 이 분야에 대한 연구는 물론 외국의 연구내용에 대하여도 적극적인 소개가 이루어지지 못하였고 아울러 여러 분야에 실제 적용은 더욱 어려웠다. 동물의 건강을 책임지고 있는 우리 수의 분야는 물론, 가축을 사양하는 축산학 분야 및 모든 동물관련 분야에서 효율적이고 바람직한 동물과 인간의 관계를 구축하기 위하여는 무엇보다도 동물의 행동을 인간의 언어사용 측면에서 이해하려는 노력이 필요하다 하겠다. 이러한 일차적인 필요성에 조금이나마 도움이 되고자 하는 바람으로 외국문헌을 중심으로 인간의 생활과 밀접한 관계를 지닌 여러 동물들의 행동과 그 의미를 소개하고자 한다. 아울러, 소개되는 내용은 Domestic Animal Behavior for Veterinarians and Animal Scientists (제3판, Katherine A. Houpt 지음), Animal Behavior (Tim Halliday 지음), Canine and Feline Behavior Problems(Stefanie Schwartz 지음), Journal of Conpendium on Continuing Education for the Practicing Veterinarian,그리고The Merck Veterinary Manual의 Behavior와 같은 참고문헌에 크게 의존하여 기술된 것임을 밝힌다.

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