• Title/Summary/Keyword: 서지

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A thermal stability testing and analysis for a surge protector installed in residential distribution board (주택용 분전반에 설치되는 서지보호기의 열적 안전성 시험 및 분석)

  • Kim, Ju-Chul;Park, Jang-Bum;Ki, Che-Ouk
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.10a
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    • pp.339-341
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    • 2009
  • Surge Protective Device(SPD) is installed by increasing information and communication equipments and home network equipments by individual home, and the amount of SPD used is increasing by revision industry regulations and strengthening equipotential grounding system. Parts of SPD installed in residential distribution board has ZnO varistor, voltage constraint type devices, but it is exposed to Temporary Overvoltage Characteristic. This thesis analyzes products through Thermal Stability test for SPD for general house and suggests the better method. As results of analysis, Gas Discharge Tube(GDT) to cut off from a leakage current and more than two kinds of safety devices to protect Thermal Runaway were needed.

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A Study of the Conceptual Modeling of MARC (MARC의 개념 모델링 연구)

  • Lee Hyun-Sil;Jeon Yang-Seung;Han Sung-Kook
    • Journal of Korean Library and Information Science Society
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    • v.36 no.3
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    • pp.275-289
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    • 2005
  • In this paper, the conceptual model for bibliographic Information consistent and compatible with MARC is presented. The modeling requirements are derived from MARC-related models such as MARC21, MARCXML and MODES. To meet these requirements, this paper proposes the conceptual model based on MARC formalism. The model composed with aggregation relationships among bibliographic data elements can use semantic tags of XML. As the model can be realized into diverse structures, it will be effectively applied for the development of bibliographic information management systems. Since MARC defines only record format and has the limitations in semantic representation, the metadata system that can expand bibliographic data elements in MRAC into metadata level is strongly required.

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A Study on Direction of Next Generation Bibliographic Network (차세대 서지네트워크의 방향성 모색)

  • Cho, Jane
    • Journal of Korean Library and Information Science Society
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    • v.42 no.2
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    • pp.85-103
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    • 2011
  • Bibliographic Network has been a goal about not only to support resource sharing within libraries but also to pursue economic efficiency of cataloging. But nowadays, as resources in diverse media and format have been poured out, printed resources based union catalog should change to new resources finding system which include diverse type of resources. This study analyzes changing factors of bibliographic network and strategies for LC, NII, OCLC, NLA who try to turn over a new service. Finally basis on these findings, suggest task for Korean new generation bibliographic network service which is focused on introducing new collaborating model and developing new resource finding system.

Countermeasure on the Suppression of Micro Surge and Noise for a Induction Motor Driven by Commercial Inverter (상용인버터 구동 유도전동기의 마이크로 서지 및 노이즈 억제에 관한 대책)

  • Kim, Duk-Hyun;Choi, Jeong-Won
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.10
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    • pp.111-117
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    • 2008
  • Generally, speed control for Induction motor widely used in industrial field is accomplished by commercial inverter. Induction motor driven by commercial inverter causes the micro surge voltage because of high speed switching of inverter. Micro surge brings about not only the breakdown of motor but also noise in PLC control system. And they court the enormous interference in activity for production. In this paper, we suggest the suppressible countermeasure for the breakdown of motor after the consideration of productive mechanism about micro surge. Experiment is performed by inverter with LCR filler in its output terminal. As a result, we confirmed that micro surge voltage is reduced. And the suppressible countermeasure for the noise of PLC control system is suggested by theoretical consideration.

A Study on Domestic and Foreign Children's Secondary Materials (국내외 어린이 관련 이차자료에 관한 연구)

  • Lee, Lan-Ju
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.20 no.4
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    • pp.17-29
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    • 2009
  • This study investigated secondary materials of children and young adults materials produced by domestic and foreign countries. In order to do that, characteristics and present states of bibliographies, indexes, union catalogs, major journals were examined while bibliography, index and catalog were defined. This study results showed that there were no bibliography and index for children and young adults materials but only recommended book catalogs and award book catalogs were produced in Korea. There were however many various second materials in foreign countries.

Bibliographic Attribute Analysis of Reading Material Based on Book Usage Data (도서이용 데이터에 기반한 독서자료의 속성 분석)

  • Jiyoung Shim
    • Journal of the Korean Society for information Management
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    • v.40 no.4
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    • pp.279-306
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    • 2023
  • This study analyzed bibliographic attributes related to the selection and use of reading materials based on data on books borrowed or purchased together in order to understand the properties of reading materials that have complex user needs from various perspectives. As a result of creating co-occurrence matrices of bibliographic attribute terms by dividing them into 26 sub-attribute units related to KDC main class, target reader, and user age, and performing network analyses, the details and prominent mediating role of bibliographic attributes of reading materials were identified. The results of this study will be helpful in designing facets of reading information systems, including library OPAC, in the future.

The Design Technology of DC Arrester for Track Line (전차 선로용 DC 피뢰기 설계 기술)

  • Han, Se-Won;Cho, Han-Goo
    • Proceedings of the KIEE Conference
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    • 2001.11a
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    • pp.259-261
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    • 2001
  • 전차 선로용으로 적용되는 직류 피뢰기의 설계 기술을 소개하였다. 현재 국내에 사용되는 전차 선로 서지 보호용 직류 피뢰기는 전량 수입에 의존하고 있다. 안전한 피뢰기를 설계하기 위해서 적용 구간의 임펄스 서지 환경을 파악하고 이에 맞는 적절한 내량의 피뢰기를 설계하는 것이 요구된다. 특히 직류 구간의 경우 과도 서지 발생의 형태가 기존 계통 환경과 다르기 때문에 피뢰기 보호범위와 정격의 설정에 주의가 요구된다.

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Analysis of Switching Surge by Recloser Operation in Distribution System (배전계통에서 재폐로 동작으로 인한 개폐서지 영향 분석)

  • Lim, Kyong-Sub;Yeo, Sang-Min;Seo, Hun-Chul;Seong, No-Kyu
    • Proceedings of the KIEE Conference
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    • 2008.11a
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    • pp.315-317
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    • 2008
  • 배전계통에서 발생한 사고의 80% 이상은 순간고장이다. 따라서, 배전계통에서 재폐로는 계통의 회복 및 신뢰도 향상을 위하여 반드시 필요한 사항이다. 그렇지만, 재폐로 순간 차단기의 동작으로 인하여 개폐서지가 발생할 수 있다 따라서 본 논문에서는 EMTP를 이용하여 고장 발생 시 차단기의 재폐로 동작을 모의하여 재폐로 동작 시 발생하는 개폐서지를 분석하였다.

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A Study on Hypertext-based Bibliographic Information Retrieval System Using Internet (인터넷을 이용한 하이퍼텍스트 기반 서지정보검색 시스템에 관한 연구)

  • 박지연
    • Journal of the Korean Society for information Management
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    • v.12 no.2
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    • pp.171-192
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    • 1995
  • In this study, we constructed a hypertext-based bibliographic information retrieval system, which is very usell tool to browse and retrieve structured data. We minimized the problem of the use; s disorientation with the keyword retrieval technique. We also presented the potential advantages of this system which could be obtained by implementing it on WWW.

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대학도서관에 있어서 서지교육을 위한 지침

  • Lee, Byeong-Mok
    • KLA journal
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    • v.19 no.6
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    • pp.17-17
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    • 1978
  • 다음 지침은 미국도서관협회 대학 및 연구도서관부회 서지교육지침작성위원회에서 작성한 것으로 1977년 1월에 열린 ACRL 이사회 동계회의에서 ACRL의 정책으로 승인되었다. 지침작성위원회는 본 단명서가 훌륭한 지침교육 프로그램에 들어가야 할 수필적인 요소들을 정확하게 반영한 것이라 믿는다. 더욱이 이러한 형태의 지침은 서지교육 프로그램을 개선하거나 개발하고자 하는 대학도서관을 도와주기 위해서도 필요한 법이다. 본 지침 ARCL이 대학도서관봉사를 개선코자 추진하고 있는 역할의 일환으로 채택하였다.

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