• Title/Summary/Keyword: 김선미

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A Study on the Turbulent Flow Characteristics in the Wake of Transom Sterns using PIV Method (동일입자추적기법을 이용한 트랜섬선미 후류 난류유동특성에 관한 연구)

  • Lee, Gyoung-Woo;Gim, Ok-Sok
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.4
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    • pp.352-359
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    • 2012
  • An experiment was carried out to figure out the turbulence flow characteristics in the wake of the transom stern's 2-dimensional section by 2-frame grey level cross correlation PIV method at Re= $3.5{\times}10^3$, Re= $7.0{\times}10^3$. The angles of transom stern are $45^{\circ}$(Model "A"), $90^{\circ}$(Model "B") and $135^{\circ}$(Model "C") respectively. The depth of wetted surface is 40mm from free surface. Strong turbulence intensity appears at the interaction between the flow separation of the bottom of a model and the free surface. This study provides statistic flow information such as turbulence intensity, Reynolds stress and turbulence kinetic energy. Model C type (Raked transom) has low Reynolds stress and turbulence kinetic energy.

The Comparison on Resistance Performance and Running Attitude of Asymmetric Catamaran Changing Angle of Inclination of Tunnel Stern Exit Region (비대칭 고속 쌍동선의 선미터널 출구영역의 경사각 변화에 따른 저항성능 및 항주자세 분석)

  • Kim, Sang-Won;Seo, Kwang-Cheol;Cho, Dea-Hwan;Kim, Byung-Jae;Lee, Gyeong-Woo
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2017.11a
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    • pp.232-233
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    • 2017
  • In this research, tunnel stern was applied on the asymmetric high-speed catamaran to evaluate vessel's hydrodynamic performance by numerical method, and the tunnel stern types are distinguished by angle of inclination of tunnel exit region into 3cases ($0^{\circ}$, $3^{\circ}$ and $6^{\circ}$). Consequently, it is confirmed that the total resistances of tunnel stern which have $0^{\circ}$ of inclination are lower about 4.8-17.9% than the bare hull in the wide speed range, but those of $3^{\circ}$ and $6^{\circ}$ of inclination tunnel stern are higher than bare hull about 5-14% and 5-29%, respectively. On the other hand, trim angles of $0^{\circ}$ of inclination tunnel stern show similar trend with those of bare hull in whole ranges of FnV but those of $3^{\circ}$ and $6^{\circ}$ of inclination tunnel stern are stabilized and declined respectively after FnV=1.54. These phenomena indicated that increasing angle of inclination of tunnel exit region had negative influence on resistance performance, however, it could make vessel's operation performance better than bare hull.

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Trends in Network and AI Technologies (네트워크와 AI 기술 동향)

  • Kim, Tae Yeon;Ko, Namseok;Yang, Sunhee;Kim, Sun Me
    • Electronics and Telecommunications Trends
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    • v.35 no.5
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    • pp.1-13
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    • 2020
  • Recently, network infrastructure has evolved into a BizTech agile autonomous network to cope with the dynamic changes in the service environment. This survey presents the expectations from two different perspectives of the harmonization of network and artificial intelligence (AI) technologies. First, the paper focuses on the possibilities of AI technology for the autonomous network industry. Subsequently, it discusses how networks can play a role in the evolution of distributed AI technologies.

CC RI processing and Final Interpretation Analysis (CC RI 처리절차 및 Final Interpretation 분석)

  • 김선미;김상호;김태훈;노병규
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 2003.07a
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    • pp.195-198
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    • 2003
  • 공통평가기준(CC: Common Criteria)은 1999년에 국제표준(ISO/IEC 15408)으로 채택되어 우리나라를 포함한 미국, 캐나다, 영국, 프랑스, 독일, 네덜란드 둥에서 사용되고 있는 IT제품 및 시스템의 보안성 평가기준이며, Interpretation 과정을 통하여 지속적으로 수정 및 보완되고 있다. 본 논문에서는 공통평가기준의 문제점 요청 및 Interpretation 제정 절차를 소개하고 현재 발표된 공통평가기준 버전 2.1의 Final Interpretation을 분석하였다.

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Designing a Personalized Portal Model based on Enterprise 2.0 (Enterpise 2.0 기반의 업무 맞춤 포털 모델 설계)

  • Song, Sang-Sup;Kim, Sun-Mi;Kim, Sun-Ho;Kang, Yoon-Soo
    • 한국IT서비스학회:학술대회논문집
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    • 2008.05a
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    • pp.364-367
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    • 2008
  • Cyber office is a personalized enterprise portal model for knowledge workers. The key services of cyber office are both personalization and emergent collaboration. Personalization service is provided by choosing service from service repository and then dropping it in the cyber office. Service repository contains various kinds of services supporting business activities. Cyber office provides blog service and profile service for knowledge workers to participate in knowledge based collaboration voluntarily.

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Wing Flutter Analysis for 4-Seat Canard-Type Small Aircraft (4인승 선미익형 경항공기 날개 플러터 해석)

  • Lee, Sang-Wook;Shin, Jeong-Woo;Kim, Jin-Won;Shim, Jae-Yeul
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.680-683
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    • 2005
  • The wing component model for flutter analysis consisting of stiffness, mass, and aerodynamic model has been constructed based on the full airframe finite element model for 4-seat canard-type small aircraft. A study on wing flutter characteristics has been investigated based on the wing component model constructed using PK method in MSC/NASTRAN for flutter analysis. In addition, wing flutter mechanism for the aircraft under consideration has been analyzed based on the results of normal mode and flutter analysis.

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