• 한국과학교육학회지
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• 제17권1호
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• pp.21-29
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• 1997

Many middle school students have difficulty in understanding biological concepts because too many concepts are presented in the textbook compared to limited school hours. So, it is necessary to select concepts which are indispensable. The purpose of this study is to select key concepts in the unit 'The Continuity of Life' by surveying students' and teachers' cognition on the concepts. In this study, 78 concepts were extracted from 'Science 3', unit II 'The Continuity of Life'. To survey how students and teachers think the concepts, Likert type questionnaires were made. 300 third grade middle school students and 34 biology teachers were selected by random sampling and the questionnaires were applied. The following results were obtained:1. Students thought 59 concepts out of 78 were important and the mean score of important level of the concepts was 3.60. Students thought 26 concepts out of 78 were difficult and the mean score of diffculty level'of the concepts was 3.26. The more they think the concepts important, the more they think them difficult (r=0.7462, p<0.001). 2. Teachers thought 55 concepts out of 78 were important and the mean score of important level of the concepts was 3.82. Teachers thought 33 concepts out of 78 were difficult and the mean score of diffculty level of the concepts was 3.31. The more they think the concepts important, the more they think them difficult (r=0.6138, p<0.001). 3. The selected concepts were considered more important by teachers than by students(t=2.0150, p<0.05). However, there was no significant difference in evaluating the difficulty level of the concepts(t=0.7327, p>0.05). 4. It was found that students have difficulty in understanding concepts when they are presented in the textbook to require formal preparation than concrete preperation(t=2.6612, p<0.05).

• 대한화학회지
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• 제58권1호
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• pp.126-129
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• 2014

본 연구는 과학학습의 어려움이나 낮은 흥미도의 한 원인으로 과학 교과학습에서의 중요한 통로 혹은 입구에 해당하는 문지방개념의 존재를 가정하고 특히 화학의 어떠한 개념들이 여기에 해당하는지를 알아보았다. 또한, 각 개념의 속성이 무엇이며 개념을 이해하고 "아~하"의 깨달음을 얻는 경험은 어떠했는지도 함께 알아보았다. 이를 위해, 화학 II를 학습한 239명의 고등학생이 연구에 참여하였고 설문에 대한 응답으로 화학 교과의 어려운 개념이 무엇인지, 문지방에 해당하는 개념이 무엇인지, 혹은 문지방개념을 이해한 경험이 화학 학습에 어떠한 영향을 주었는지를 설명하였다. 몰과 원자구조가 화학 교과의 문지방개념으로 제시되었고 구체적으로는 제시된 두 개념이 문지방개념이 되는 속성이 무엇인지를 집중적으로 분석하였다. 문지방을 극복하고 이해하는 것은 각자의 경험에 따르지만, 문지방개념을 분석하는 기준은 각각의 경험에 일정한 준거를 제시하여 서로 다른 경험들을 객관화 시킬뿐 아니라 개념의 과학적 의미와 본성을 잘 드러내어 준다. 특히, 교사가 제시하는 화학의 문지방개념을 조사한 사전연구와의 비교는 문지방개념의 통합적 속성이 학생들의 학습과 과학흥미도 증진에 중요함을 보여준다.

• 대한수학교육학회지:학교수학
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• 제17권4호
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• pp.571-591
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• 2015

분수는 초등학교 수학의 수영역에서 중요한 개념 중 하나임에도 불구하고 자연수와 다른 양적 개념과 표기법, 다양한 분수 개념으로 인하여 교수 학습이 어렵다. 따라서 분수의 교수학적 변환은 중요하며, 이를 연구하기 위해 한국 교과서에서 사용하고 있는 분수의 교수학적 개념이 어떠한지 살펴볼 필요가 있다. 본 연구는 한국, 대만과 중국의 초등학교 수학 교과서를 비교하여 각 나라의 교과서에 나타난 분수 개념이 교수학적 개념에 따라 지도 시기와 순서가 어떻게 달라지는지, 양적 개념에 따른 지도 방법의 차이는 어떠한지 알아보았다.

• 한국과학교육학회지
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• 제6권2호
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• pp.35-42
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• 1986

Recent studies on the learning of the science concepts indicate that most students have misconceptions of the science concepts. The misconceptions have their roots in the various aspects of teaching and learning situations. The textbooks used in schools have been substantiated as one of the sources of the misconceptions. Genetics has been recognized as one of the most difficult areas for high school students to learn. Therefore, this study had its objective to identify the misconceptions of genetics held by high school students and analyze the high school biology textbook as the source of the misconceptions. In order to indentify the misconceptions of the genetic concepts, the volunteer students were interviewed and genetic content and its sequence in the high school biology textbooks were analyzed. The misconceptions identified in this study are as follow: gamete formation, mitosis, trait expression, and allele and gene behavior in meiosis. This study found that the high school biology textbooks might be the source of those misconceptions. Based on the misconceptions identified, this study proposed direction for efficient instruction of genetics in high schools.

• Journal of Radiation Protection and Research
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• 제20권3호
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• pp.201-213
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• 1995

비이온화방사선(NIR)에 대한 방어는 증가되는 관심의 주제가 되고 있지만, 방사선의 유형이나 그 적용간의 의존되는 아주 다른 개념의 사용은 이 분야에서의 통일된 방법의 자료편집에 어려움을 주고 있다. 이 논문의 주된 목적은 비 이온화방사선 방어의 목적으로 확실하게 사용하는 개념, 양, 단위 및 전문용어를 제공하기 위해서이다. 그 외에 방사선방어의 표준과 피폭한도를 양으로 나타내는데 사용되는 특별한 개념과 주어진 양들의 체계적인 분류와 비교를 요약하고 또 논하였다.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제13권2호
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• pp.75-90
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• 2009

There are concepts in calculus which are difficult to teach and learn. One of these concepts is integration. However, problem posing has not yet received the attention it deserves from the mathematics education community. There is no systematic study that deals with teaching of calculus concepts by problem posing oriented teaching strategy. In this respect this study investigated the effect of problem posing on students' (prospective teachers') academic success when problem posing oriented approach is used to teach the integral concept in Calculus-II (Mathematics-II) course to first grade prospective teachers who are enrolled to the Primary Science Teaching Program of Education Faculty. The study used intervention-posttest experimental design. Quantitative research techniques were employed to gather, analyze and interpret the data. The sample comprised 79 elementary prospective science teachers. The results indicate that problem posing approach effects academic success in a positive way and at significant level.

• 대한지리학회지
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• 제37권4호
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• pp.425-441
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• 2002

본 연구는 협동적 상호작용 중심의 교수-학습을 통해서 학습자의 지리개념과 근접발달영역이 어떻게 발달하는가를 살펴보았다. 연구 결과, 학습자의 개념발단은 인지구조 수준이 논아질수록 일상적인 개념에서 벗어나 지리적 개념을 표현하는 과정으로 이루어졌다. 지리적 개념의 표현은 구체적인 사실들에서 하위요소개념. 그리고 기본요소개념의 위계적인 순서로 상향 발달하였으며, 발달 과정에서 학습자가 인지구조로 내면화하는데 가장 어려운 개념은 기본요소개념이었다. 학습자의 수도권 개념에 대한 근접발달영역은 9개 유형으로 나타났다. 근접발달영역은 사전 인지구조가 지리적 개념을 얼마나 더 많이 그리고 더 체계적으로 표상하는가의 질적 차이에 따라 다르게 발달했다. 지리개념 발달은 학습자의 사전 인지구조보다는, 교수-학습을 통해서 자신의 인지구조를 얼마나 적극적이고 능동적으로 재구성하느냐에 달려 있었으며, 표상한 개념의 양적 증가를 바탕으로 한 질적 변화의 과정으로 이루어졌다.

• Journal of Mechanical Science and Technology
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• 제19권5호
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• pp.1072-1079
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• 2005

Conceptual design is the first step in the overall process of product design. Its intrinsic uncertainty, imprecision, and lack of information lead to the fact that current conceptual design activities in engineering have not been computerized and very few CAD systems are available to support conceptual design. In most of the current intelligent design systems, approach of principle synthesis, such as morphology matrix, bond graphic, or design catalogues, is usually adopted to deal with the concept generation, in which optional concepts are generally combined and enumerated through function analysis. However, as a large number of concepts are generated, it is difficult to evaluate and optimize these design candidates using regular algorithm. It is necessary to develop a new approach or a tool to solve the concept generation. Generally speaking, concept generation is a problem of concept synthesis. In substance, this process of developing design candidate is a combinatorial optimization process, viz., the process of concept generation can be regarded as a solution for a state-place composed of multi-concepts. In this paper, genetic algorithm is utilized as a feasible tool to solve the problem of combinatorial optimization in concept generation, in which the encoding method of morphology matrix based on function analysis is applied, and a sequence of optimal concepts are generated through the search and iterative process which is controlled by genetic operators, including selection, crossover, mutation, and reproduction in GA. Several crucial problems on GA are discussed in this paper, such as the calculation of fitness value and the criteria for heredity termination, which have a heavy effect on selection of better concepts. The feasibility and intellectualization of the proposed approach are demonstrated with an engineering case. In this work concept generation is implemented using GA, which can facilitate not only generating several better concepts, but also selecting the best concept. Thus optimal concepts can be conveniently developed and design efficiency can be greatly improved.

• Industrial Engineering and Management Systems
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• 제15권2호
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• pp.181-195
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• 2016

In a product environment where various product-service systems (PSSs) are already being provided, the provision of a different type of PSS is difficult for second movers but necessary for their sustainability and differentiation. Despite the importance of providing distinguishing PSSs to market, prior PSS studies have not effectively considered the influence of existing PSSs in their methods. In response, we suggest an approach to generate new PSS concepts by employing general needs (GNs) and business system evolution patterns (BSEPs). Our approach 1) identifies customer GNs fulfilled by existing PSSs, 2) generates advanced PSS ideas from an evolutionary perspective by mapping the existing PSSs onto BSEPs, and 3) selects PSS ideas that can meet the unfulfilled or insufficiently considered GNs using a GN-PSS linking matrix, thereby generating new PSS concepts based on the selected ideas. The workings and practicability of this approach are illustrated using a PSS case study of furniture industry. This approach would provide PSS planners with an ability to generate the differentiated PSS concepts that handle the customer needs that have been untapped throughout a product's lifecycle. In addition, this approach as a module will have a synergetic effect when incorporated with other PSS methodologies.

• 한국수학교육학회지시리즈A:수학교육
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• 제46권3호
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• pp.315-329
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• 2007

The concepts of ratio, rate, and proportion are used in everyday life and are also applied to many disciplines such as mathematics and science. Proportional reasoning is known as one of the pivotal ideas in school mathematics because it links elementary ideas to deeper concepts of mathematics and science. However, previous research has shown that it is difficult for students to recognize the proportionality in contextualized situations. The purpose of this study is to understand how the mathematical concept in the middle school mathematics curriculum is connected with ratio, rate, and proportion and to investigate the characteristics of proportional reasoning through analyzing the concept including ratio, rate, and proportion on the middle school mathematics curriculum. This study also examines mathematical concepts (direct proportion, slope, and similarity) presented in a middle school textbook by exploring diverse interpretations among ratio, rate, and proportion and by comparing findings from literature on proportional reasoning. Our textbook analysis indicated that mechanical formal were emphasized in problems connected with ratio, rate, and proportion. Also, there were limited contextualizations of problems and tasks in the textbook so that it might not be enough to develop students' proportional reasoning.