• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.1238-1243
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• 2002

In this study, the validity of the acoustic impedance model and the estimation model by electro-acoustic analogy suggested by Maa for predicting the absorptive performance of multiple layer perforated plate systems is investigated. From the comparison between the experiment and calculation for the absorption performance of double layer perforated plate system, the calculated results of using Rao and Munjal's impedance model and transfer matrix method are closer to the experimental values than those of using Maa's impedance model and electro-acoustic analogy. Therefore, in order to apply the acoustic impedance model and the estimation model by electro-acoustic analogy suggested by Maa to the multiple layer perforated plate systems, it is necessary that the suggested acoustic impedance and estimation models should be re-examined.

• 한국소음진동공학회논문집
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• 제13권3호
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• pp.180-185
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• 2003

The equivalent electroacoustic circuit approach has been conventionally used for the analysis of the multiple layer perforated plate system. However, it is found that an analogy error has been involved in the equivalent electroacoustic approach proposed by previous researchers for the element of straight pipe. Although the pipe between the perforated layers is a distributed element in the analogy, it has been treated as a parallel element by previous investigators. The analogy error is demonstrated by comparing the calculated absorption coefficients based on the parallel circuit and the distributed circuit, respectively, with the measured values by the two-microphone impedance tube method.

• 한국과학교육학회지
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• 제21권1호
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• pp.114-121
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• 2001

본 연구에서는 다중 비유의 사용 방식이 중학생들의 과학 개념 이해에 미치는 효과를 조사하였다. 7학년 학생 127명에게 다중 비유의 사용 방식(비유물의 개수, 비유물과 목표물의 대응 회수, 비유물간 유사성 비교)이 다른 네 가지 유형의 비유 학습 교재 중 하나를 무선 배포하여 읽게 한 후, 개념 검사를 실시하였다. 분석 결과, 비유물이나 대응 과정을 2번 사용하는 것은 과학 개념의 회상 및 응용에 유의미한 영향을 주지 않았다. 그러나 비유물간의 유사성 비교는 과학 개념 응용에서 유의미한 효과가 있었다. 이에 대한 교육학적 함의를 논의하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.890-895
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• 2002

The equivalent electroacoustic circuit approach has been conventionally used for estimating the absorption coefficient of a single layer perforated plate system. When the single layer system is extended to the multiple layer ones, however, it is found that an analogy error has been involved in the equivalent electroacoustic parallel circuit approach proposed by previous investigators. The analogy error is demonstrated by the corrected equivalent electroacoustic circuit approach in this study.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.387.2-387
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• 2002

The equivalent electroacoustic circuit approach has been conventionally used for estimating the absorption coefficient of a single layer perforated plate system. When the single layer system is extended to the multiple layer ones, however, it is found that an analogy error has been involved in the equivalent electroacoustic parallel circuit approach proposed by previous researchers. The analogy error is demonstrated by the corrected equivalent electroacoustir circuit approach proposed en this study.

• 한국과학교육학회지
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• 제19권3호
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• pp.471-478
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• 1999

In this study, the relationships among learners' cognitive variables, motivational variables, and conceptual understandings in learning with analogy were investigated. The instruments regarding analogical reasoning ability, field dependence-independence, mental capacity, and logical thinking ability were administered. Some subtests (self-efficacy, expectancy, self-concept of ability, and value) of the Patterns of Adaptive Learning Survey were administered. After students learned with a worksheet that included analogy, a conception test regarding 'stoichiometry that included limiting reagent' was also administered. It was found that learners' conceptual understandings were significantly correlated with the logical thinking ability and the field dependence-independence among the cognitive variables, and the self-efficacy and the self-concept of ability among the motivational variables. The multiple regression analysis of the cognitive variables on conceptual understandings revealed that the logical thinking ability was the most significant predictor. The field dependence-independence also had predictive power. In the analysis of the motivational variables, the self concept of ability was the only significant predictor.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제17권1호
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• pp.1-16
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• 2014

본 연구는 유추 거리 및 수학적 지식과 학습의 전이 사이의 관계를 규명하기 위해 수행되었다. 구체적으로 유추적 거리에 따라 구분된 세 가지 전이 문제 해결에서 차이를 보이는지, 그리고 각 전이 문제를 성공적으로 해결하는데 기여하는 수학적 지식은 무엇인지를 분석하였다. 분석 결과 세 가지 종류의 전이 문제 해결에서 통계적으로 유의한 차이를 보였으며 유추 거리가 증가할수록 성공률은 점차적으로 감소하였다. 또한 사실 지식 보다는 개념적 지식이 전이 문제를 해결하는데 긍정적으로 기여하였다. 이상의 결과를 토대로 본 연구는 학습의 전이를 위해 수학 수업은 어떠한 점에 초점을 맞추어야 하는지, 그리고 유추 거리라는 새로운 구인을 찾고 그것이 전이에 미치는 영향을 실증적으로 규명했다는 점에서 의의를 찾을 수 있었다.

• 대한화학회지
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• 제45권2호
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• pp.177-182
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• 2001

비유 추론의 도식 이론과 요소 과정 이론을 바탕으로 다중 비유를 요소 과정에 따라 사용한 MACP 수업 모형을 고안하였다. 이 모형은 다중 비유물 소개, 비유물의 공통 속성 추출, 목표 상황 제시, 비유물고 목표물의 대응, 목표 개념 도출, 다른 상황에서의 적용 등 6단계로 구성되었다. 이 모형의 교수 효과를 학생들의 개념 이해와 학습 동기의 측면에서 TWA 모형에 의한 수업 및 비유를 사용하지 않는 수업과 비교하였다. 중학교 2학년 3개 반을 선정하여 MACP 집단, TWA 집단, 통제 집단으로 무선 배치한 후, 화학 변화와 화학 반응에 대한 수업을 10차시 동안 실시하였다. 공변량 분석 결과, MACP 집단의 과학 개념 검사 점수가 통제 집단에 비해 유의미하게 높았으나, 학습 동기 검사 점수는 집단간에 유의미한 차이가 나타나지 않았다.

• 한국자동차공학회논문집
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• 제12권4호
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• pp.65-73
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• 2004

Fatigue crack growth from surface defects is one of the most important subjects for the evaluation and the assurance of safety in pressure vessels, piping systems, LPG/LNG fuel tank and other various structures. This paper attempts to analysis some practical or general problems such as the estimation of crack growth life to penetrate the plate thickness, based on fatigue crack growth a single surface flaw and the interaction of multiple flaws. An experiment on the coalescence of multiple undercuts was carried out under cyclic tension condition as a attempt to the analysis of multiple crack problems. It is noted that the fracture strength is characterized by the analogy to that in a single crack growth.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.317-322
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• 2001

A mathematical modelling technique is proposed for estimating the additional bending stresses of tube(s)-in-tube structures due to tube-tube interaction, which has a significant effects on the shear-lag phenomenon. The proposed method simulates the framed-tube structures with multiple internal tubes as equivalent multiple tubes, each composed of four equivalent orthotropic plate panels. Hence, the tube(s)-in-tube structure can be analysed by using an analogy approach where each tube is individually modelled by a continuous beam that can account for the flexural and shear deformations as well as the shear-lag effects. The numerical analysis is applicable for the structural analysis of framed-tube structures with single and multiple internal tubes, as well as those without internal tubes. The shear-lag phenomenon of such structures is studied with additiona] bending stresses and shear-lag reversal points.