• Title/Summary/Keyword: 이태영

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Analysis of PLL Dynamic Characteristics according to Zero Voltage Conditions of Single-phase Grid-connected Inverter (단상 계통연계형 인버터의 영 전압 사고 위상에 따른 PLL 동적 특성 분석)

  • Lee, Taeil;Lee, Kyungsoo
    • Proceedings of the KIPE Conference
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    • 2019.07a
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    • pp.80-82
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    • 2019
  • 태양광발전과 풍력발전으로 대표되는 분산형 전원이 계통에 연계됨에 따라 계통 사고 발생 시에 계통연계형 인버터에 대한 각국의 계통 규정(Grid code)이 더욱 엄격해 지고 있다. 최근 국외 계통 규정에서는 저 전압 사고뿐만 아니라 영 전압 사고 시에 인버터가 일정 시간 계통 연계를 유지하며 무효전류 출력 기법을 통해 계통 복구를 지원할 것을 요구하고 있다. 계통 사고 시, 사고 전압 잔존량에 따라 무효전류를 정확하게 출력하기 위해 인버터의 PLL(Phase Locked Loop) 제어는 중요하다. 그러나 이러한 PLL 제어의 동적 특성은 계통 사고 순간의 전압 강하 및 사고 위상에 따라 영향을 받게 되고 영 전압 사고에서는 위상 추종이 불가능하기 때문에 복합적인 문제가 나타난다. 본 논문에서는 영 전압 사고에서 사고 위상에 따라 각각 다르게 나타나는 PLL 동적 특성을 시뮬레이션을 통해 분석하였다.

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A Study of Heat Flow and Residual Stress Analysis in Pipe-plate Gas Metal Arc Brazing (파이프-평판 GMAB 접합부의 열유동 및 잔류음력 해석에 관한 연구)

  • 이태영;김재웅;이목영;정평석
    • Journal of Welding and Joining
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    • v.19 no.4
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    • pp.413-422
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    • 2001
  • In this study. two-dimensional heat flow and residual stress in arc brazing to join the pipe and plate structure were analyzed by using a commercialized FEM package. Advantages offered by arc brazing are that strong joints can be produced with lower heat input than that of previous gas metal arc welding and narrower heat affected zone can usually be obtained than that in the case of torch brazing. To investigate the effects of process variables and minimize the thermal effects on the structure, this study presents a method for analyzing the heat flow and residual stress in arc brazing process according to variables such as traveling speed, torch angle and position. The simulation results were compared with the experimental ones to verify the numerical analysis method. The experiments include the measurement of HAZ size from the section of joints and residual stresses by using strain gages named 'section method'. A comparatively good agreement between the results of numerical analysis and experimental ones could be obtained in both of the temperature distribution and residual stress of the brazed structure. Using the proposed numerical analysis method, the process parameters were evaluated to get proper arc brazing conditions.

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Construction of harbor foundation using deep mixing method (심층혼합고결처리공법을 이용한 항만구조물 기초설치에 관한 연구)

  • 한우선;이태영;임우성
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.841-846
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    • 2003
  • The purpose of this paper is to present and discuss some of harbor foundation constructed on seashore soft ground by Deep Wing Mixing in deep mixing method. A series of laboratory and field experiments including unconfined compressive strength, permeability, geo-physical survey, sea water concentration, lateral and settlement measurement, field core sample were carried out to check physical, mechanical and environmental characteristics of solidified foundation soil treated by HWS solidifying agent. The results from this research showed that Deep Wing Mixing method could be efficiently applied in the construction site of seashore structure foundation.

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Study on the Information Policy and Online System Development in Korea (한국(韓國)의 도서관정보정책(圖書館情報政策)과 온라안화(化)에 대(對)한 연구(硏究))

  • Lee, Tae-Young
    • Journal of the Korean Society for information Management
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    • v.3 no.1
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    • pp.50-69
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    • 1986
  • Making the efficient Information Supply System has been the essential Research area for developing the Nation's Industry and Culture. With the Information Policy and its System Situation in Europe, America, and Japan, the Present position of Libraries and Information Centers in Korea is Compared and analyzed for the well organized Information System Structure. The result, Coordination Committee between Libraries, Integrated Information Center disseminated various subject and type of Data, and the Support of DNS being possessed by DACOM are required.

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A CASE REPORT OF RECONSTRUCTION USING METALLIC CONDYLAR PROSTHESES FOR THE CORRECTION OF COMPLICATIONS RESULTED BY UNSUCCESSFUL MANAGEMENT OF FRACTURED MANDIBULAR CONDYLE (하악두 골절의 미진한 처치로 인해 metallic condylar prostheses까지 사용한 증례)

  • Chung, Hoon;Sung, Choon-Su;Lee, Tae-Young
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.16 no.1
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    • pp.43-50
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    • 1994
  • It is a generally known fact that the patient can experience mouth opening limitation, mandibular deviation and malocclusion as a result of injury of tissues around the articular disc and complications even after successful open reduction surgery for fractured mandibular condyle. We have experienced a rare case of reconstruction using metallic condylar prostheses for a patient with complications resulted by unsuccessful management of fractured mandibular condyle. The case strongly suggested to us that careful selection of treatment methods should be taken for patient with fractured mandibular condyle. Accordingly, we are presenting a case in conjunction with reviews of fractured mandibular condyle.

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