• Journal of Korean Elementary Science Education
• /
• v.41 no.2
• /
• pp.283-294
• /
• 2022

Although the concept of light is important in the elementary school curriculum, substantial research suggests that students and teachers have difficulties in understanding it. Therefore, it is necessary to analyze the reasons for these difficulties-whether it is due to the content or due to the presentation method of contents, structure, and expression. The national curriculum and textbooks of Korea, the US, China, and Japan were comparatively analyzed from the following perspectives: 1) key concepts of light, 2) structure of light units in the textbook, 3) materials, light sources, and optics used in light units. Consequently, there were differences between countries in their inclusion of the concept of light in the curriculum. In particular, the Korean curriculum studies the concept of refraction by a convex lens, whereas the concept of light, light source, and vision is not introduced. Furthermore, countries also differed in their structuring of units. The Korean curriculum was presented segmentally by concept rather than structured according to core ideas or perspectives, and the connection between concepts was unclear. In addition, there were differences between the countries in materials, light sources, and optical instruments to explain key concepts. On using light, the US curriculum provides a purpose and uses light to achieve it, and China and Korea understand the concept. It was divided into the method of using the material to deepen. Based on the results of this analysis, the implications for the elementary science curriculum in Korea were derived as follows. First, it is necessary to introduce concepts sequentially and organize them so that the connection between concepts is well expressed. Second, it is necessary to introduce light and light sources as the predominant concepts. Third, it is necessary to include the principle of seeing objects. Fourth, it is necessary to adjust the material and content level of the refraction concept included in the light and lens unit. Fifth, an integrated approach is required because light has a deep connection with various concepts included in the elementary science curriculum.

• School Mathematics
• /
• v.18 no.1
• /
• pp.159-173
• /
• 2016

In real educational field, there are cases that concrete problematic situations are introduced after abstract concepts are taught on the contrary to process that abstract from concrete contexts. In other words, there are cases that abstract knowledge has to be concreted. Freudenthal expresses this situation to antidogmatical inversion and indicates negative opinion. However, it is open to doubt that every class situation can proceed to abstract that begins from concrete situations or concrete materials. This study has done a comparative analysis in difference of mathematical thinking between a process that builds abstract context after being abstracted from concrete materials and that concretes abstract concepts to concrete situations and attempts to examine educational implication. For this, this study analyzed the mathematical thinking in the abstract process of concrete materials by manipulating AiC analysis tools. Based on the AiC analysis tools, this study analyzed mathematical thinking in the concrete process of abstract concept by using the way this researcher came up with. This study results that these two processes have opposite learning flow each other and significant mathematical thinking can be induced from concrete process of abstract knowledge as well as abstraction of concrete materials.

• Journal of KIISE:Software and Applications
• /
• v.36 no.11
• /
• pp.928-935
• /
• 2009

Ontology schema reasoning is used to maintain consistency of concepts and build concept hierarchy automatically. For the purpose, the search of concepts must be inevitably performed. Ontology schema reasoning performs the test of subsumption relationships of all the concepts delivered in the test set. The result of subsumption tests is determined based on the creation of complete graphs, which seriously weighs with the performance of reasoning. In general, the process of creating complete graph has been known as expressive procedure. This process is essential in improving the leading performance. In this paper, we propose a method enhancing the classification performance by identifying unnecessary subsumption test supported by optimized searching method on subsumption relationship test among concepts. It is achieved by propagating subsumption tests results into other concept.

• Journal for History of Mathematics
• /
• v.21 no.3
• /
• pp.53-66
• /
• 2008

The concepts of ratio and proportion are familiar with students but have difficulties in use. The purpose of this paper is to identify the meanings of the concepts of ratio and proportion through investigating the historical development process of the meanings and representations of them. The early meanings of ratio and proportion were arithmetical meanings, however, geometrical meanings had taken the place of them because of the discovery of incommensurability. After the development of algebraic representation, the meanings of ratio and proportion have been growing into algebraic meanings including arithmetical and geometrical meanings. Through the historical development process of ratio and proportion, it is observable that the meanings of mathematical concepts affect development of symbols, and the development of symbols also affect the meanings of mathematical concepts.

• Journal of Educational Research in Mathematics
• /
• v.26 no.3
• /
• pp.333-354
• /
• 2016

The aim of the present study is twofold. One is to confirm a hypothesis that a student's rate concept influences her conceiving change of a function in the view of rate of change and the other is to build up foundations for understanding the transition process from her rate concept to the concept of rate of change when she investigates the change of concentration as an intensive quantity. We explored how three participating high school students recognized and expressed change of given functions by using their rate concept as a conceptual tool. The result indicates that a change in students' rate concept might have an effect on understanding how function values change in term of rate of change. We also expect that it could be a catalyst for further research for clarifying the relationship between students' rate concept and their development of a concept of rate of change as a foundation for learning calculus.

• Journal of the Korean School Mathematics Society
• /
• v.16 no.4
• /
• pp.841-862
• /
• 2013

This study analyzed issues in the mathematics curriculum concerning the cognitive development of the vector and inner product concepts in the light of Tall's and Watson's research(Tall, 2004a; Tall, 2004b; Watson et al., 2003; Watson, 2002). Some suggestions in teaching the vector and inner product concepts were elaborated in the terms of these analyses. First, the position vector needs to be represented by an arrow on the coordinate system in order to introduce the component form of a vector represented by a directed line segment. Second, proofs of the vector operation law should be carried out by symbolic manipulations based on the algebraic concept of a vector in the symbolic world. Third, it is appropriate that the inner product is defined as $\vec{a}{\cdot}\vec{b}=a_1b_1+a_2b_2$ (when, $\vec{a}=(a_1,a_2)$, $\vec{b}=(b_1,b_2)$) when it comes to considering the meaning of the inner product relevant to vector space in the formal world. Cognitive growth of concepts of the vector and inner product can be properly induced through revising explanation methods about the concepts in the curriculum in the basis of the above suggestions.

• Journal of the Korean Geographical Society
• /
• v.37 no.4
• /
• pp.425-441
• /
• 2002

This study focused on the geographical concepts development and its zone of proximal development(ZPD) through the collaborative interaction. Among the conclusions are: 1) Students who have higher cognitive structure represented the Creator Seoul Metropolitan Area(GSMA) as a geographical concepts, not as a spontaneous concepts. The concepts is developed from concrete facts, subordinate element concept to basic element concept hierarchically. The most difficult concept that the learner should internalize was represented as the basic element concept. 2) Although ZPD of GSMA is individualized, it could be divided into 9 types. The ZPD was developed differently according to the qualitative differences how much more and how systematically represented the geographical concepts. The characteristics shown in this development procedure was that there was a quality change based on quantity extensive.

• Journal of Educational Research in Mathematics
• /
• v.24 no.1
• /
• pp.67-82
• /
• 2014

The term "objectification" has various definitions or perspectives. Nevertheless, it's pursued commonly by groups from various perspectives who emphasize the activities of becoming aware of a process as a totality, realizing that transformations can act on that totality, that is, turning processes into object. The purpose of this study is to identify how students objectify the concept of repetition regarding permutation and combination and find difficulties of objectification focusing on teacher's and students' discourse from common emphasis on previous researches associated with objectification. Students objectified the concept of repetition by replacing talk about processes with talk about objects regarding repetition and using discursive forms that presented phenomena in an impersonal way. The difficulties of objectification were derived from close linkage between the way of using keywords regarding repetition and everyday language.

• Proceedings of the Korean Society for Cognitive Science Conference
• /
• 2005.05a
• /
• pp.177-181
• /
• 2005

기계학습에서 커널을 이용한 방법은 그 응용범위가 기계학습의 전반에 걸쳐 다양하게 이용되고 있으며, 그 성능 또한 기존의 방법들을 앞지르고 있다. 이는 기존의 비선형적 접근을 커널을 이용한 고차원 공간에서의 선형적 접근법으로 바꿈으로써 가능하게 되는 것이다. 다양한 분야에 적용되는 많은 커널들이 존재하며 각 커널들은 특별한 분야에 적용되기 쉽도록 다른 형태를 띠고 있기도 하지만, 커널로서 작용하기 위해 양한정 조건(positive definiteness)을 만족해야 한다. 본 연구에서는 DNA 문제에 직접 적용시킬 수 있는 방법으로서의 새로운 커널을 제시한다. 또한 매트로폴리스(Metropolis) 알고리즘을 이용하여 DNA의 hybridization과정을 모사함으로써 새로운 종류의 커널이 양한정(positive definite) 조건을 만족시킬 수 있는 방법을 제시한다. 새로 만들어진 커널이 행렬값을 형성해 나가는 과정을 살펴보면 인간이 예(instance)로부터 개념을 형성해 나가는 과정과 흡사한 양상을 보이는 것을 알 수 있다. 개념을 나타내는 좋은 예로서의 표본(prototype)으로부터 개념이 형성되어 가는 과정은 표본(prototype)이 아닌 예로부터 개념이 형성되는 과정과 다른 양상을 띠는 것과 같은 모양을 보인다.

• KOMUNHWA
• /
• no.65
• /
• pp.5-29
• /
• 2005

The purpose of this study is to understand a basic concepts and a series of individual processes for the planning of cultural heritage sites management in order to establish effective cultural heritage sites management plans in South Korea. In order to pr