• 한국초등과학교육학회지:초등과학교육
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• 제42권4호
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• pp.538-559
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• 2023

본 연구에서는 과학교육 전문가 5인으로 구성된 포커스 그룹 토의(FGD)를 활용하여 모델 및 모델링에 관한 의미를 토의하는 과정에서 주요 주제로 다루어진 '모델과 이론의 관계'를 탐색하였다. 7회 수행된 FGD는 과학교육 연구에서 활발히 진행되고 있는 '모델 및 모델링'과 관련하여 '모델 혹은 모델링이란 무엇인가'라는 질문을 출발로 하여 토의가 전개되었다. 토의 과정에서 이론과의 관계를 중심으로 모델 및 모델링에 관한 몇 가지 주요한 논제가 제기되었고, 본 연구는 그 논제를 중심으로 전개된 토의의 흐름을 추적하였다. 이 연구에서 주목한 것은 FGD에서 연구 참여자들의 이론과 모델의 관계에 대한 토의가 하나의 주장으로 수렴되지 않고, 그와 관련된 몇 가지 논제들이 새로 불거져 나오는 상황은 그 논제에 대한 기존의 개념을 탈바꿈하고 새로운 이해를 추구하는 시도로 이어졌다는 점에 있다. 연구 결과는 세 가지 논제, '모델 혹은 모델링이란 무엇인가?', '모델과 이론의 관계는 어떠한가?', '이론에 기반하지 않은 모델링은 가능한가?'를 포괄하며, 특히 모델과 이론의 관계는 1) 모델이 이론 연역적이고, 모델링이 이론을 현상에 적용하는 것으로 이해되는가, 2) 모델이 이론으로 귀납되는가, 3) 모델링이 특정 구조를 갖는 바탕이론(경험적 지식의 틀)을 기반으로 출발하거나 혹은 바탕이론이 명시적으로 드러나지 않은 채 여러 가지 다른 자원들의 연결로 이해되는가로 토의되었다. 연구의 결과를 토대로, 과학철학과 과학교육, 그리고 과학교육 연구자와 과학교사 교육에 대한 함의가 제시되었다.

• 한국과학교육학회지
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• 제35권5호
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• pp.919-929
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• 2015

본 연구에서는 지질구조에 대한 모델링기반 학습 프로그램을 개발하고 모델링기반 학습에서 나타나는 논증패턴과 학생들의 정신모형 수준과의 관계를 밝히고자 하였다. 고등학교 2학년 126명을 대상으로 대륙이동설, 해령, 변환단층, 단층의 특징에 대하여 4회의 모델링기반 학습을 실시하였다. 연구대상 중에서 2개 학급은 실험집단으로 모델링기반 학습을 실시하였고 나머지 2개 학급은 비교집단으로 교사중심 설명식 수업을 실시하였다. 모델링기반 학습 후 실험집단과 비교집단의 사후 성취도와 학생들의 정신모형 분포를 정량적으로 비교하였다. 실험집단 중 5개 조의 논증활동을 녹음 전사한 자료에 대하여 본 연구에서 설정한 분석틀을 근거로 정성적으로 분석하였다. 본 연구의 분석틀은 TAP의 5가지 요소와 학생들의 대안개념이 포함되는 요소 5가지 등 총 10가지의 코딩 요소로 구성하였다. 정신모형 유형을 조사한 결과, 실험집단에서 단면 인과모형과 입체형 모형의 비율이 높게 나타난 반면, 비교집단에서는 2차원 모형과 단면 단순모형의 비중이 높게 나타났다. 논증유형을 분석한 결과, 주장의 빈도가 높을수록 논증활동이 성공적으로 이루어졌고 정신모형의 수준이 높게 나타났다. 반박이 제기된 경우, 만든 모형을 다시 관찰하여 자료를 수정하고, 이에 따라 주장을 다시 전개하였다. 이로써 모델링기반 학습에서 모형이 학생들의 논증 과정에 긍정적으로 작용함을 확인할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.310-312
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• 1994

A partial shunt regulator (PSR) which is the power regulator of KOREASAT is modeled. The modeling of the PSR consist of solar array, power circuit, controller. and load models. To realize simple structure. a voltage source of the PSR controller is used the output voltage of the PSR. The model of the PSR has very complex structure with two additional coupled feedback loops. The complex model is simplified to a simple meaningful model with only main feedback control loop. The proposed model is compared to a PSR model with DC voltage source at the PSR controller. The proposed PSR model is verified by comparing the model with SPICE simulation for small signal analysis.

• KIEE International Transactions on Power Engineering
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• 제4A권2호
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• pp.51-57
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• 2004

This paper describes the dynamic performance of a variable speed wind turbine system responding to a wide variety of wind variations. Modeling of the wind generation using power electronics interface is proposed for dynamic simulation analysis. Component models and equations are addressed and their incorporations into a transient analysis program, PSCAD/EMTDC are provided. A wind model of four components is described, which enables observing dynamic behaviors of the wind turbine resulting from wind variations. Controllable power inverter strategies are intended for capturing the maximum power under variable speed operation and maintaining reactive power generation at a pre-determined level for constant power factor control or voltage regulation control. The components and control schemes are modeled by user-defined functions. Simulation case studies provide variable speed wind generator dynamic performance for changes in wind speed

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.1268-1275
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• 2005

The computerization works and environment have been changed from simple transaction and data process request to system connection request, from data computerization to application work automation and process computerization through IT development and Internet spread. Recently, BPM(Business Process Management) concept has been widely propagated. It is expanding interest of business subject. Korea Railroad is operating train operation management system through 5 regional headquarters and organizations under the influence of each regional headquarter. But integrated operation and management of communication each department, work flow management and resources of depot equipment and materials have to need a lot of effort and time in huge organization as Korea Railroad. Therefore, this article realized Web Based BPM Group Ware. This article will define Korea Railroad organization and business process in using this Group Ware. And it will introduce Korea Railroad computer manage system of this Group Ware and efficient Korea Railroad Business Process through modeling and operating department work and resources management in Korea Railroad.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1266-1271
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• 2009

Formwork layout is perceived as important due to its strong tie to site works. But, most formwork is done manually and influenced by worker's skill and thus, a lot of construction errors occur. The introduction of BIM (Building Information Modeling) enables acquiring more precise information on the building shape, dimension, structure, etc. than 2D-based drawings and thus, the increased productivity, such as reduction of workload and work times, and the economic efficiency, such as reduction of formwork types and form dimensions with the consideration of constructability, are expected. This study reviewed the previous studies and formwork layout systems to derive this study's differentiations and factors to be first considered for formwork planning were derived by analyzing priorities against consideration factors. Last, a flow chart and algorithm were developed to apply the derived factors to the formwork layout module.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.587-592
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• 2009

Construction companies in Korea have shown interest in BIM (Building Information Modeling) even if late, adopted it, and applied it to several projects. But, it is hard to figure out the status of BIM implementation. Thus, this study is to figure out the status of BIM implementation in Korea by surveying major construction companies in Korea and comparing with similar surveys abroad. The survey result shows that only 11 companies in Korean construction industry adopted BIM. The clash check (73%) was mostly used among various BIM functions and other functions were used less than 30%. As of 2008, only 8 construction companies have used BIM in 27 projects and thus, Korean companies are in the BIM introduction period. Therefore, successful introduction of BIM is required by benchmarking the BIM introduction process of overseas construction industries

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.139-144
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• 2005

A rigorous research is underway in our team, for the design and development of high figure of merits (ZT= 1.5${\sim}$2.0) micro-thermoelectric coolers. This paper discusses the fabrication process that we are using for developing the $Sb_2Te_3-Bi_2Te_3$ micro-thermoelectric cooling modules. It describes how to obtain the mechanical properties of the thin film TEC elements and reports the results of an equation-based multiphysics modeling of the micro-TEC modules. In this study the thermoelectric thin films were deposited on Si substrates using co-sputtering method. The physical mechanical properties of the prepared films were measured by nanoindentation testing method while the thermal and electrical properties required for modeling were obtained from existing literature. A finite element model was developed using an equation-based multiphysics modeling by the commercial finite element code FEMLAB. The model was solved for different operating conditions. The temperature and the stress distributions in the P and N elements of the TEC as well as in the metal connector were obtained. The temperature distributions of the system obtained from simulation results showed good agreement with the analytical results existing in literature. In addition, it was found that the maximum stress in the system occurs at the bonding part of the TEC i.e. between the metal connectors and TE elements of the module.

• 연구윤리
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• 제2권1호
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• pp.19-24
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• 2021

Purpose: The purpose of this study is to check the direction of KODISA's pursuit of complex and convergence studies by confirming the research trends of KODISA's direct academic journals such as JDS, JIDB, JBEES and JAFEB. To this end, we tried to compare and confirm the research trends of the papers in four academic journals targeting keywords. Research Design, data and methodology: The analysis was conducted from 2014 to 2020 on 867 papers from JDS, 315 papers from JIDB, 120 papers from JBEES, and 867 papers based on the publication year of the most recently published journal from JAFEB. For the analysis, frequency analysis, word crowding, topic modeling, and frequency analysis by applying weights for each year group were performed on the keywords crawled using Python. Results: The results of frequency analysis showed that each journal is properly oriented toward its target direction. In addition, it was confirmed that the results of topic modeling significantly reflected the results of frequency analysis. Finally, it could be concluded that the results of frequency analysis using the weights of keywords by year group were also developing in the direction the target journals were analyzed. Specifically, in the case of JDS, 20 keywords such as Service Quality, Distribution were found to increase continuously according to the year group. Meanwhile, the keywords that continued to increase according to JIDB's year group were India, Social Capital, and Job Stress. The keywords that continued to increase according to the year group of JBEES were Micro Finance Institutions and Microfinance, and the keywords that of JAFEB were confirmed to be Vietnam and Service Quality. Conclusion: It was confirmed that KODISA's direct management journals responded appropriately to convergence issues. In particular, it was confirmed that researches in various fields of JDS are continuously increasing. However, it seems that JIDB needs to deal with various issues additionally in the service industry field and JBEES in the environment field. Finally, it was found that JAFEB needs to be wary of the relatively low level of interest in some countries such as Kazakhstan and India in recent years.

• 한국과학교육학회지
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• 제39권6호
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• pp.799-807
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• 2019

이 연구는 과학중점학교의 1학년 프로그램이 학생들의 과학과 핵심역량과 과학학습동기를 향상시키는지 확인하기 위하여 진행되었다. 과학중점학교 1학년 프로그램은 과학탐구 기초교육, 조사 발표, 심화실험, 소논문 기초교육 등으로 구성된다. 프로그램 참여자는 총 262명이며, 설문 검사를 모두 수행한 학생은 169명이다. 집단중심 추세모형 분석을 통해 유사한 점수 변화 보이는 집단으로 구분하였다. 연구 결과 과학중점학교의 1학년 프로그램은 학생들의 과학과 핵심역량과 과학학습동기를 유의미하게 향상시켰다. 집단중심 추세모형분석 결과 약 40~60%의 학생들이 프로그램의 효과를 보았다. 인문계열을 선택한 학생들 중에서도 효과가 나타나는 학생들이 있었으며, 과학중점 계열을 선택한 학생 중에서도 교육적 효과가 나타나지 않는 학생들도 일부 있었다. 집단중심 추세모형 분석을 통해 개별 학생들의 변화 과정을 확인할 수 있는 방법론적 효과를 확인하였다. 이 연구는 과학중점학교 정책의 긍정적 효과를 통계적으로 확인하였으며, 과학중점학교 프로그램의 효과 분석을 위한 사례로서 의미가 있다.