• 한국과학교육학회지
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• 제21권2호
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• pp.255-263
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• 2001

중학교 '전기와 자기' 에 대한 개방적 탐구 과제는 관찰을 통한 서술적인 결과 처리가 특징인 정성적 과제와, 변인통제를 통한 정량적 결과 처리가 특징인 정량적 과제로 나눌 수 있다. 본 연구의 목적은 두 종류의 과제에 대한 중학교 2학년 학생들의 탐구 수행 특징을 탐구 과정을 중심으로 분석하는 것이다. 학생이 작성한 '탐구 보고서' 및 '탐구 활동 평가서' 그리고 연구자의 관찰 및 면담 자료를 분석하였다. 정성적인 과제에 대한 탐구에서는 자신의 생각과 다른 뜻밖의 관찰을 인지하고 처리하는 것이 어려운 점이었고, 정량적인 과제에 대한 탐구에서는 여러 개의 변인을 다루고, 신뢰롭고 타당한 측정을 하며, 정량적으로 결과를 처리하는 것이 어려운 점이었다. 정성적인 과제에 대한 탐구에서는 자신이 제시한 탐구 방법 및 결과의 부족한 점을 인지하고 있었는데 반해, 정량적인 과제에 대한 탐구에서는 부족한 점을 거의 인지하지 못했다. 이러한 결과는 기존의 실험실습과는 다른 개방적인 탐구를 지도할 때, 정성적인 과제의 경우 뜻밖의 관찰 결과를 신뢰롭고 타당하게 처리하도록 지도하는 것이 중요하며, 정량적인 과제의 경우 여러 개의 변인을 다루는 방법 및 신뢰롭고 타당한 측정 방법을 지도하는 것이 중요하다는 것을 시사한다.

• 정보관리연구
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• 제42권4호
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• pp.1-21
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• 2011

본 연구에서는 국내 학술지의 국제적 이용 활성화를 위한 방안으로서 적합한 모델을 제시하였다. 최근 DOI와 오픈액세스가 국내 학술지의 국제적 노출 및 인용 기회 확대 차원에서 관심 모아지고 있음에 따라, DOI와 오픈액세스의 활용 모델을 분석함과 아울러 국내외적 추진 현황을 조사하였다. 현황 조사와 데이터 분석은 KAMJE, KISTI, DOAJ, SCIMAGO 등의 자료를 활용하였다. 이를 기반으로 국내 학술지의 국제적 이용 활성화를 위해서 학술논문 식별자인 DOI를 활용하고 학술지의 오픈액세스를 동시에 추진하는 방안을 제시하였다.

• Journal of Power Electronics
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• 제9권6호
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• pp.949-959
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• 2009

This paper presents a systematic investigation of the fault-mode behaviors of matrix converter systems. Knowledge about converter behaviors after fault occurrence is important from the standpoint of reliable system design, protection and fault-tolerant control. Converter behaviors have been, in detail, examined with both qualitative and quantitative approaches for key fault types, such as switch open-circuited faults and switch short-circuited faults. Investigating the fault-mode behaviors of matrix converters reveals that converter operation with switch short-circuited faults leads to overvoltage stresses as well as overcurrent stresses on other healthy switching components. On the other hand, switch open-circuited faults only result in overvoltage to other switching components. This study can be used to predict fault-mode converter behaviors and determine additional stresses on remaining power circuit components under fault-mode operations.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2006년도 추계학술발표대회 논문집
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• pp.448-451
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• 2006

Multi-residential housing in Korea has many problems basically because maintenance, management, and remodelling have been done without considering building elapse and residents' needs. Residential open building has been suggested as one of the solutions. Even though the techniques have been actively developed for residential open building in Japan and the Netherlands, some obstacles are still existing. Especially in Korea, due to the lack of studies for facilitating residential open building, the development and popularization of residential open building are delayed. With the concern that the facilitation of process and systems is as important as technical development, the evaluation of process and systems is needed for promoting residential open building. As result, strong investigation of current situation can offer basic foundation to facilitate residential open building. The purpose of this study is to propose plans to facilitate residential open building in Korea through a comparative study between Korean and Japanese system.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권1호
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• pp.56-69
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• 2015

This paper presents a numerical study on investigating on hydrodynamic characteristics of a marine propeller in oblique flow. The study is achieved by RANS simulations on an open source platform - OpenFOAM. A sliding grid approach is applied to compute the rotating motion of the propeller. Total force and moment acting on blades, as well as average force distributions in one revolution on propeller disk, are obtained for 70 cases of combinations of advance ratios and oblique angles. The computed results are compared with available experimental data and discussed.

• 무역상무연구
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• 제69권
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• pp.633-654
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• 2016

Recently open data has been spread rapidly in the world include Korea. Accordingly in international trade field open data and using it became a key point to get competitiveness. In this study, the author make an attempt to suggest the way for quality improvement of international trade information by looking for some problems with crating and using the information. Thus, the problems of using information are can be point out as follows. Firstly the range of open data is narrow. Secondly the management of the open data is not conducted properly. Thirdly the suppliers of the open data didn't prepare some investigation system for their data's usability for user. Expansion of the organizations who open data is one way to solve quantitative problem. There are four suggestions to solve qualitative problems. Firstly the guidelines should be established and operated in each organizations respectively. Secondly the criterion of expenses for open data should be arranged among the concerned parties. Thirdly the ability of the manpower and organization who charged in the quality improvement of information should be reinforced both quantitatively and qualitatively. Lastly the system for data usability for user should be equipped in early stages. Finally the author emphasize the establishment of total management system for using open data in international trade is not needed only the efforts of the specific parties but also all parties led by Ministry of Industry, Trade and Energy in order to carry out above suggestions successfully.

• 대한치과교정학회지
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• 제16권1호
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• pp.35-49
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• 1986

전치개교에 관한 원인과 여러가지 치료법의 장단점을 논의했고 전치개교본태를 객관적으로 이해하는데 강조했다. 진단의 주관적인 해석은 부정교합을 잘못 기술해서 위험한 결과를 흔히 유도하게 된다. 해부학, 생리학, 조직학과 교정기계요법의 역학에 관한 길은 지식을 가진다면 대부분 전치개교치료는 외과적중재 없이 높은 성공율과 안정을 기할 수 있다. 이러한 점에서 지난 20여년동안 임상적으로 정립된 Kim의 MEAW 시술을 설명했으며 전치개교치료증례들이 이 MEAW요법을 입증하는데 제시되었다.

• 한국수학교육학회지시리즈A:수학교육
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• 제43권3호
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• pp.275-289
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• 2004

The purpose of the study is to investigate how children and preservice teachers would make a progress in solving the open-problems related to area. In knowledge-based information age, information inquiry, information construction, and problem solving are required. At the level of elementary school mathematics, area is mainly focused on the shape of polygon such as square, rectangle. However, the shape which we need to figure out at some point would not be always polygon-shape. With this perspective, many open-problems are introduced to children as well as preservice teacher. Then their responses are analyzed in terms of their logical thinking and their understanding of area. In order to make students improve their critical thinking and problem solving ability in real situation, the use of open problems could be one of the valuable methods to apply.

• Smart Structures and Systems
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• 제23권6호
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• pp.553-564
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• 2019

Modeling of magnetorheological (MR) dampers for cable vibration control to facilitate the design of even more effective and economical systems is still a challenging task. In this study, a parameter-adaptive three-element model is first established for a full-scale MR damper based on laboratory tests. The parameters of the model are represented by a set of empirical formulae in terms of displacement amplitude, voltage input, and excitation frequency. The model is then incorporated into the governing equation of cable-damper system for investigation of open-loop vibration control of stay cables in a cable-stayed bridge. The concept of optimal voltage/current input achieving the maximum damping for the system is put forward and verified. Multi-mode suboptimal and Single-mode optimal open-loop control method is then developed. Important conclusions are drawn on application issues and unique characteristics of open-loop cable vibration control using MR dampers.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2005년도 추계학술대회 논문집
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• pp.157-162
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• 2005

It is necessary for us to research and analyze of Open Housing in order to change new housing system, because exiting multi family housing is lack of flexibility and easy remodeling. The purpose of this study is to supply and grasp basic planning and design data for flexibility of Open Housings in Korea. This study is based on the literature survey and actual investigation through visiting 17 open housing sites from 1995 to 2005 in Netherlands, Finland and Japan, which are main Open Housing. We analyzed the planning methods and elements for flexibility of open housing block and unit plan, and described the contents of analyses. We found a lot of planning and design methods-supplying option plan and user participation before occupation, various structural system for openness, common piping shaft location, slab-down and applying access flooring system, movable and demountable partition wall system etc. -applied to the open housings, and findings are applicable to the planning and designing works of apartment housings in Korea.