• Journal of the Korean Magnetics Society
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• v.26 no.5
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• pp.159-167
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• 2016

We have examined the perceptions of 6th grade elementary school students' conceptions on the magnetic fields of a permanent magnet by cognitive style. Students' conceptions on the magnetic fields of permanent magnet after the iron powder experiment are grouped into four models; Partial Distribution Model (PDM), Pole Separation Model (PSM), Homogeneous Distribution Model (HDM), and Field Model (FM). After the experiment to observe the magnetic field of the permanent magnet with compass, the students' conceptions are grouped into three models; Pole Separation Model (PSM), Complex Homogeneous Distribution Model (CHDM), and Field Model (FM). And after the application of the alternative experimental method to observe the magnetic field with only one compass, students' conceptions on magnetic field has been enhanced in both field-dependent and general-cognitive groups of students.

• Journal of Korea Water Resources Association
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• v.30 no.3
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• pp.279-291
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• 1997

This study is to evaluate the accuracy and practicality of the existing four conceptual models, two linear models of Clark and Nash model and two nonlinear models of Laruenson and WBN model, and to select an appropriate model to simulate the rainfall-runoff process in a given catchment. The variability of parameters for linear models is generally larger than that of nonlinear models. The errors in peak discharge are similar among the four conceptual models buy the errors in time to peak are quite different. Nonlinear models produce better results for time distribution than linear models. A comparison of the conceptual models to predict overall hydrograph using Friedman two-way analysis of variance by rank test indicates that nonlinear models are slightly better than linear models.

• Journal of The Korean Association For Science Education
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• v.24 no.3
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• pp.621-637
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• 2004

In science education, the research on students' conceptions has been started in early 1970. From the early 1980, the research on students' conceptions stimulated the research on conceptual change. Recently, mental model has been a theoretical background in concrete arguments on "how students' conceptions are constructed or created?" Mental model has been studied early in cognitive psychology, and several researchers have studied it partially in science education area. In this study, we compared different theories that explained students' conceptions in, mainly, physics. Further we discussed the possibility of mental model as a theory that could integrate different explanations about students' conceptions from different theory.

• Journal of The Korean Association For Science Education
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• v.30 no.5
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• pp.557-575
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• 2010

The purpose of the study was to suggest the characteristics and goals of the science teaching model for use as criteria in selecting the appropriate teaching model for science in secondary schools. These characteristics and the goals have been organized based on the analyses of the literature on the teaching and/or instructional model. The teaching models have been classified into four areas, and the characteristics and goals of each area have been summarized as follows: $\cdot$ Traditional models: teaching of scientific knowledge through lectures, acquisition of scientific knowledge through discovery, acquisition of inquiry process skills through inquiry-based teaching/learning $\cdot$ Transitional models: demonstration and discovery as teaching strategies, acquisition of inquiry process skills through inquiry approach, acquisition and change of scientific knowledge $\cdot$ Modernistic model - conceptual change models: differentiation of scientific knowledge, exchange of misconceptions for scientific concepts - learning cycle models: conceptual differentiation, exchange of misconceptions, acquisition of science process skills Also described in this paper are the model's characteristics and goals that can be used as the criteria for selecting the appropriate teaching model for the subject that will be taught.

• Korean Journal of Cognitive Science
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• v.17 no.1
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• pp.53-74
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• 2006

Similarity has been considered as one of basic concepts of cognitive psychology which is useful for explaining cognitive structure and process. MDS models(Shepard, 1964; Nosofsky, 1991) and Contrast model(Tversky, 1977) were proposed as early models of similarity comparison process. But, there have been a lot of theoretical doubts about the conceptual validity of similarity as a result of empirical findings which could not be explained by early models. Goldstone(1994) assumed that similarity could be defined by alignment processes, and suggested structural alignment as a prospective alternative for solving conceptual controversies so far. In this study, basic assumption and algorithms of MDS models(Shepard, 1944; Nosofsky, 1991) and Contrast model(Tversky, 1977) were described shortly and some theoretical limitations such as arbitrariness of selective attention and correlated structures were discussed as well. The conceptual characteristics and algorithms of SIAM(Goldstone, 1994) were described and how it has been applied to cognitive psychology areas such as categorization, conceptual combination, and analogical reasoning were reviewed. Finally, some theoretical limitations related with data-driven processing and alternative processing and possible directions for structural alignment were discussed.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.99-99
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• 2015

본 연구에서는 금강 유역을 대상으로 토양저류함수모형기반의 개념적 강우유출모형의 장기 유출모의를 평가하였다. 연구유역인 금강 22개 계측유역을 주요 유역특성인자(면적, 경사도, SCS-CN등)을 수문학적 거리 산정방법을 활용하여 3개의 유역그룹을 선정하였다. 적용모형인 개념적 강우유출모형은 3개의 토양저류함수모형[확률분포모형(PDM: Probability Distributed Moisture), 유역습윤지수모형(CWI: Catchment Wetness Index), 수정펜맨타입모형(MP: Modified Penman type model)]과 3개의 유역추적모형[병렬2선형 저류지 유출 모형(2PAR: 2-conceptual reservoirs in parallel), 빠른 지표하 흐름을 고려한 병렬 2선형 저류지 유출모형(2PMP: 2Macro-pre Approach parallel structure), 병렬 3선형 저류지 유출모형(3PAR: 3-conceptual reservoirs in parallel)]의 조합인 9개의 모형을 사용하였으며, 2006년부터 2012년의 일자료를 바탕으로 검정(Calibration), 2001년부터 2005년의 일자료를 검증(Validation)을 Monte carlo method(Uniform Random Sampling)로 수행 후, 모형의 성능은 NSE(Nash sutcliffe Efficiency)로 평가하였다. 분석결과 유역그룹에 대한 모형성능의 편차는 작아서 유역그룹에 대한 토양저류 함수모형의 뚜렷한 상관성을 확인할 수 없었다. 이는 금강 유역을 단일 유역 그룹으로 적용할 수 있음을 제시하고 있다. 검정 검증성능 및 검정매개변수의 개수를 바탕으로 적용성 평가를 실시한 결과에서 토양저류함수모형인 확률분포모형(PDM)과 유역추적모형의 병렬2선형 저류지 유출모형(2PAR)와 빠른 지표하 흐름을 고려한 병렬2선형 저류지 유출모형(2PMP)의 조합이 금강 22개 유역에서 적용성이 우수함을 확인하였다. 향후 이 모형을 바탕으로 금강유역의 대표적인 강우유출모형을 개발하고자 한다.

• Journal of The Korean Association For Science Education
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• v.31 no.5
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• pp.734-744
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• 2011

The purpose of this study was to identify middle school students' mental models on plate tectonics and to compare the mental models of verbal-learning-style students with those of visual-learning-style students. 94 student participants in 9th grade were requested to draw and explain three topics; generation of magma, the formation of the mountain range and the interior of the Earth. The criterions for analyzing the mental models are derived from the data of the drawing task. The research results were as follows: The mental models on the generation of magma were classified as 'unstable model,' 'partial casual model,' 'causal model,' and 'conceptual model.' On the other hand, the mental models on the interior of the Earth were classified as 'static unstable model,' 'dynamic unstable model,' and 'conceptual model.' Students holding 'unstable model' were unable to relate the plate collision and the magma generation. They showed a variety of alternative conceptions of study areas, such as 'magma is generated from the core' and 'the mountain is formed by rising of the plates themselves.' Also, visual-learning-style students showed higher proportion of conceptual models and lower proportion of unstable mental models than verbal-learning-style students on three topics. The findings revealed that the students tend to have different concepts on the plate tectonics depending on their learning style.

• Journal of Korea Technology Innovation Society
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• v.18 no.1
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• pp.204-231
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• 2015

This study aims to present a conceptual model for technology valuation based on market approach. We first propose a transition model in which technology itself is endowed with its intrinsic value based on its technology- and market-specific features, which subsequently goes through a transition to the market perceived value. We also discuss the model's logical validity. Based upon the transition model, we develop market approach based technology valuation models by identifying factors comprising each component of the transition model for each case of fixed royalty and running royalty. We also show that the proposed model can be used to describe the relationship between cost, income and market approaches for technology valuation.

• Journal of the Korean earth science society
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• v.28 no.6
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• pp.645-654
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• 2007

The purpose of this study was to investigate students' mental models and alternative conceptions about the Earth's interior. A total of 126 10th grade students participated in this study. They were requested to draw Earth's interior tasks and were interviewed about their mental models. A coding frame was designed to classify the students' drawings and interview responses, and then a four step cognitive model was established based on the frame of coding. In addition, the relationship of mental models was compared in terms of students' gender, and the type of alternative conceptions was analysed. The research results showed a variety of alternative conceptions on the interior of the Earth. The classified mental models showed naive mental model (11%), unstable mental model (81%), conceptual model (8%), while 69% of all sampled students accounted for the static process. The gender difference in the cognitive model showed no statistical significance.

• Journal of Distribution Research
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• v.9 no.2
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• pp.101-122
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• 2004

In this study, two alternative models are developed and tested in order to investigate the relationship between retailer image and its private brand attitude. The halo effect model hypothesizes that retailer image is related as a halo in private brand evaluation and the summary construct model hypothesizes that retailer image functions as a summary construct of private brand evaluation. The results indicate there are moderating effects of 1) familiarity with a private brand and 2) the characteristics of a product category High familiarity is related with the summary construct model and low familiarity the halo effect model. In private brand food, the summary construct model fits better and explains more adequately that private brand evaluation influences retailer image as a summary construct. In private brand clothes, however, the halo effect model performs better in explaining the relationship between retailer image and private brand attitude.