• 한국과학교육학회지
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• 제17권4호
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• pp.461-479
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• 1997

개념도는 학습내용에서 주요 개념들을 추출하여 위계적으로 배열하고 그 관계를 나타낸 것이다. 1995년 개정된 제6차 교육과정에서 고등학교 지구과학 검인정 교과서 10종 중 5종의 내용을 분석하고 1종을 선택하여 개념도를 작성하였다. "III. 우주"단원은 지구 밖의 환경을 다루며 별과 우주에 대한 새로운 개념들이 다양하게 제시되며 천문학의 최근 연구들이 소개된다. 교과서에 있는 내용을 Novak의 방법에 의한 개념도를 작성하여 교과서에 있는 개념 중 학습자의 수준에서 개념을 획득하기 위하여 보충되어야 할 개념을 찾고 문제점을 작성하였고 이를 근거로 개선된 개념도를 작성하였다. 다음과 같은 결론을 얻었다. 첫째, 보다 효과적인 이해를 위해 필요없는 소단원명은 제외하고 내용 전개상 관련있는 개념들 간의 연관성을 살린 재배열이 필요하다. 둘째, 상위 개념과 하위 개념의 체계적인 전개가 요구된다. 셋째, 개념들의 학습이 잘 되도록 학습 개념과 관련있는 실례를 찾아 학습자의 경험과 인식에 관련을 맺도록 해야 한다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.200-202
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• 2007

Improvement of LC mixtures can be realized by the development of new molecules in combination with the identification of advanced mixture concepts. By new high-polar single materials rotational viscosity has recently been improved significantly. Now, a new LC mixture concept for IPS and FFS technology has been identified which additionally improves switching time by up to 10%. This advanced concept is based on a more efficient usage of high-polar materials and Super Low Viscous (SLV) compounds and simultaneous reduction of less efficient materials.

• 한국응급구조학회지
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• 제1권1호
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• pp.87-99
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• 1997

The purpose of this study was to analyze and confirm the correlation between self-concept and the degree of satisfaction on field practice of EMT students. Data were collected from 66 junior college EMT students by quertionaire from August 12 to 13, 1997. The data were analyzed by percentage, mean, t-test, F-test, and Person correlation using SAS program. The results of this study were as follows : 1. Self-concept level revealed to be high as 3.784 of a total score 5.0. 2. Satisfaction level revealed to be low as 2.970 of a total score 5.0. Satisfaction level of teaching revealed to be high and environments revealed to be low. 3. Subject satisfaction, practice time were significant in satisfaction level on field practice. 4. Self-concept was not influenced to the degree of satisfaction on field practice.

• 한국수학교육학회지시리즈A:수학교육
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• 제61권2호
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• pp.323-338
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• 2022

이 연구의 목적은 중학생과 고등학생의 사각형에 대한 개념 정의 이해 정도를 분석하고 개념 이미지에 대한 현상을 탐색하는 것이다. 이를 위해 검사 도구를 개발하고 중학교 2학년 60명, 중학교 3학년 63명, 고등학교 1학년 65명을 대상으로 검사하고, 일부의 학생을 면담하였다. 연구 결과는 다음과 같다. 첫째, 학년이 올라감에 따라 자연적으로 사각형의 개념 정의에 대한 이해도가 향상된다고 볼 수 없다. 특히, 모든 학년에서 다른 사각형과 비교하여 마름모 개념 정의에 대한 이해도가 가장 낮은 것으로 나타났다. 둘째, 정사각형에 대한 개념 정의는 여학생이 남학생보다 더 잘 이해하지만, 사다리꼴, 평행사변형, 마름모, 직사각형에 대한 개념 정의에 대한 이해 정도는 성별로 차이가 없는 것으로 나타났다. 셋째, 사각형 개념 정의를 이해하지 못하는 학생은 학년이 올라갈수록 개념 이미지의 영향을 점점 더 크게 받는 것으로 나타났다. 넷째, 학년이 올라갈수록 학생의 사각형에 대한 개념 이미지 형성에 개념 정의의 영향은 줄어들고 교과서나 교사의 영향이 증가하는 경향을 보여주었다.

• 한국과학교육학회지
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• 제19권3호
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• pp.479-486
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• 1999

중학교 생물의 광합성과 호흡단원에 대해 개인별 또는 협동 학습개념도를 적용한 수업결과를 전통적 강의식 수업결과와 비교하였다. 그 결과 개념도를 적용한 학습이 전통적 강의식 수업보다 효과적이었다. 공분산분석을 실시하여 개인별 개념도 작성그룹과 협동 개념도 작성그룹간(p<.008), 협동개념도 작성그룹과 전통적 강의식 학습그룹간(p<.0001)에 유의성있는 결과를 얻었다. 또한 협동개념도작성그룹이 개인별 개념도 작성그룹보다 효과적이었다(p<.04). 따라서 협동개념도 학습방법이 생물학습에 있어 가장 효과적이었다.

• 한국학교수학회논문집
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• 제4권1호
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• pp.103-114
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• 2001

The purpose of this study is to develop learning materials for functional concept on variable and to verify the effect of how well students could learn functional concept after they studied with those materials. To accomplish the purpose of this study, I developed learning materials and after teaching students with them. I have concluded the followings : First, there was little effect in teaching functional concept on variable between two experimental groups, whereas teaching functional concept had greater effect on forming functional concept in high level groups in those two experimental groups. Second, teaching functional concept on variable had little effect on students' understanding of functional concept and perfecting tables in Black box, graph, and mathematical problems, whereas there was much effect in students' understanding functional concept and solving relation formula, image, and range problems related to everyday life or general things. On the basis of the problems which appeared in the process of this study, the following can be suggested : First, we should develop learning materials fit for low level students so that they could understand functional concept. Second, we should continue to teach the basic problems like solving relation formula, image, and range, and understanding functional concept in graph until students are able to understand them exactly. Third, since the goals of Unit Function in a middle school textbook is to solve problems related to everyday life through functional thinking, there should be change in constructing systematic contents of Unit Function in a middle school textbook.

• 대한가정학회지
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• 제46권9호
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• pp.113-123
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• 2008

The purpose of this study was to investigate how parenting and peer relationships influence the development of adolescent self-concept by using Structural Equation Modeling(SEM). The subjects were 198 first graders (94 male and 104 female) from four high schools within the Seoul area. Descriptive and comparative statistical analysis was conducted with SPSS (Version10.0), while AMOS (Version 4.0) was used to assess structural equation modelling of parenting, peer relationship and the self-concept. Results showed that, in terms of correlation, more positive parenting behaviors induced more positive self-concept. In addition, better peer relationships demonstrated more positive self-concept. Regression analysis showed that peer relationships explained the variance in adolescents' self-concept more effectively than parenting behavior. This was confirmed by the SEM.

• International Journal of Contents
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• 제2권1호
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• pp.17-21
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• 2006

In this paper, we describe a concept-based question-answering system in which concept rather than keyword itself makes an important role on both question analysis and answer extraction. Our idea is that concepts occurred in same type of questions are similar, and if a question is analyzed according to those concepts then we can extract more accurate answer because we know the semantic role of each word or phrase in question. Concept frame is defined for each type of question, and it is composed of important concepts in that question type. Currently the number of question type is 79 including 34 types for person, 14 types for location, and so on. We experiment this concept-based approach about questions which require person s name as their answer. Experimental results show that our system has high accuracy in answer extraction. Also, this concept-based approach can be used in combination with conventional approaches.

• Journal of Power Electronics
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• 제8권4호
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• pp.332-344
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• 2008

High frequency AC (HFAC) power distribution systems delivering power through a high frequency AC link with sinusoidal voltage have the advantages of simple structure and high efficiency. In a multiple module system, where multiple resonant inverters are paralleled to the high frequency AC bus through connection inductors, it is necessary for the output voltage phase angles of the inverters be controlled so that the circulating current among the inverters be minimized. However, the phase angle of the resonant inverters output voltage can not be controlled with conventional phase shift modulation or pulse width modulation. The phase angle is a function of both the phase of the gating signals and the impedance of the resonant tank. In this paper, we proposed a pulse phase modulation (PPM) concept for the resonant inverters, so that the phase angle of the output voltage can be regulated. The PPM can be used to minimize the circulating current between the resonant inverters. The mechanisms of the phase angle control and the PPM were explained. The small signal model of a PPM controlled half-bridge resonant inverter was analyzed. The concept was verified in a half bridge resonant inverter with a series-parallel resonant tank. An HFAC power distribution system with two resonant inverters connected in parallel to a 500kHz, 28V AC bus was presented to demonstrate the applicability of the concept in a high frequency power distribution system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.835-840
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• 2008

Next Generation High Speed Train having a distributed electrical motor system has just been developing to aim the experimental maximum speed at 400km/h since August, 2007. This project is in stage of concept design and so, it needs to take some review and analysis the characteristics of suspensions on the view of concept design. A vehicle modeling is made of modified Korean High Speed Train bogie model with Vampire program and analyzed the effect on the dynamic performances according to the variation of primary and secondary suspension characteristics. The results would be useful to manage the potential risks in the next stage of basic and precision design that will be done by the manufacturing company.