• Journal of Technologic Dentistry
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• v.23 no.1
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• pp.9-19
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• 2001

Microstructure and phase transformation of Ti-Ni-Cu alloy powders produced by using attrition milling method were studied. Mixed powders of Ti-(50-X)Ni-XCu ($X=0{\sim}20$ at%) in composition range were mechanically alloyed for maximum 20 hours by using SUS 1/4" ball in argon atmosphere. Ball to powder ratio was 50: 1 and impeller speed was 350rpm. Mechanically alloyed with attrition millimg method. powder was heat treated at the temperature up to $850^{\circ}C$ for 1 hour in the $10^{-6}$ torr vacuum. Ti-Ni-Cu alloy powders have been fabricated by attrition milling method. and then phase transformation behaviours and microstructual properties of the alloy powders were investigated to assist in improving the the high damping capacity of Ti-Ni-Cu shape memory alloy powders. The results obtained are as follows: 1. After heat treating of fully mechanically alloyed powder at $850^{\circ}C$ for 1hour. most of the B2 and B 19' phases was formed and $TiNi_3$ were coexisted. 2. The B 19' martensite were formed in Ti-Ni-Cu alloy powders whose Cu-content is less than 5a/o. where as the B19 martensite in those whose Cu-content is more than 10at%. 3. The powders of as-milled Ti-Ni-Cu alloys whose Cu-contents is less than 5at% are amorphous. whereas those of as-milled Ti-Ni-Cu alloys whose Cu-content is more than 10at% are crystalline. This means that Cu addition tends to suppress amorphization of Ti-Ni alloy powders.

• Journal of the Korean Geographical Society
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• v.48 no.3
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• pp.466-481
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• 2013

The purpose of this research is to propose a model for education for sustainable development (ESD) within the geography curriculum. The study consists of two parts. The first part discusses the normal view of a model to assess the curriculum, namely the content and the cognitive dimensions. The ESD component necessitates an action program with skills and citizenship considered as the Objective Dimension. The second part of the paper examines the means for adding the Objective Dimension which follows a taking action approach through knowledge, skills, and citizenship that are consistent with ESD goals. The research procedure applied the methodology of the Delphi process. The theoretical model was initially developed by the researchers based on current practices in geography assessment in South Korea and the U.S. The model was tested using the Delphi technique by high school geography teachers and geography education faculty members in both countries who were recognized experts in their field. The research complements the curriculum and instructional activities that have been under way with the United Nations Decade of Education for Sustainable Development (UNDESD). The model may be used to deliberate proposals for building an ESD component into existing assessment practices.

• Korean Journal of Environment and Ecology
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• v.19 no.2
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• pp.83-89
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• 2005

To investigate the vegetation structure of mountain ridge from Bubong to Poamsan, 16plots$(400m^2)$ set up with random sampling method were surveyed. Two groups of Quercus mongolica-Pinus densiflora community, Quercus variabilis-Pinus densiflora-Quercus mongolica community were classified by cluster analysis. Quercus mongolica was a major woody plant species in the ridge area from Bubong to Poamsan, and Quercus variabilis and Pinus densiflora were partly occupied in lower elevations. High positive correlations were proved between Lespedeza maximowixcii and Pinus koraiensis, Fraxinus sieboldiana and Rhododendron mucronulatum, Acer mono and Weigela subsessilis, and relatively high negative correlations were proved between Symplocos chinensis for. pilosa and Fraxinus sieboldiana, Rhododendron mucronulatum. Species diversity(H') of investigated groups were ranged from $0.9066\~1.0821$, and it was relatively low value compared to that of mountain ridge area of other national parks.

• Journal of the Korean School Mathematics Society
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• v.10 no.4
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• pp.471-485
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• 2007

In this study, a 27 class hour prescribed program for the fourth grade students is to be developed and applied by extracting the contents associated with basic operations studied prior to the fourth grade level of mixed calculations. After analyzing the results of the research, the following conclusions are obtained. First, the prescribed program for mixed calculations brought about the improvement in the mixed calculation problem solving ability of the students. Second, applying the prescribed program for mixed calculation resulted in an increase in students' interest and concentration on problem solving. In synthesis of the above conclusions, the development and application of the prescribed program for mixed calculation improved the students' concentration on the problem and the students' problem solving ability.

• Journal of The Korean Association of Information Education
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• v.10 no.3
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• pp.289-298
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• 2006

Computer education is important to learn functions of computers, and it is necessary to enhance the ability such as high-power intelligence ability, originality, and positive thoughts on the future. In other words, not only is it important to learn functions to calculate using computers but also it is important to understand the principle of the way computers calculate and enlarge other abilities to solve other problems through understanding of the principle. Accordingly, this study aims to teach search and sort of data structure to a primary-school children. In addition its purpose is to design teaching and learning methods and teach according to the methods and find out whether primary-school children can understand the contents. Intelligent field was assessed through equivalent test before and after the test and emotional field through students' impressions after a lesson. The test showed that search and sort algorithm of data structure could be taught to children. That is, it presented the learnability of search and sort of data structure as a learning element of elementary school computer education.

• Journal of The Korean Association of Information Education
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• v.10 no.3
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• pp.341-351
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• 2006

Robot education is the learning instrument suitable for the logical thinking and problem solving ability of students, but in the elementary school, research data for curriculum, teaching material developing, and special teacher for the purpose of efficient robot education is rare. So this study investigated and researched on the educational use of robot as the instrument for enhancement of the logical ability and the problem solving ability of elementary school students. In order to introduce contents related to robot in the elementary, I investigated and analyzed what is discussed. I analyzed their opinions for the efficient robot education of the elementary school student through the questionary survey of the elementary school teacher in charge of robot education in the discretion activity class. and I suggested the condition of robot, proper contents, the form of robot, and teaching & learning method suitable for introduction in the elementary school curriculum based on analyzed contents.

• Journal of The Korean Association of Information Education
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• v.14 no.1
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• pp.111-121
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• 2010

The aim of this study is to investigate the effects of game-based robot education on the elementary students' logical thinking ability and academic achievement. 12 boys in the 6th grade from S elementary school from Namhae, Kyungnam participated in the study. The game-based robot education was applied to the participants 32 times in the procedures. The results from pre- and post-logical thinking tests and pre- and post-academic achievement were analyzed. After participating in the game-based robot education activities, there were meaningful statistical differences in the participants' logical thinking ability. The results of the study suggest that the game-based robot education has positive impact on students' ability to think logically. In addition, the game-based robot education improved children's motivation in learning.

• Journal of The Korean Association of Information Education
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• v.22 no.1
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• pp.131-140
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• 2018

The KAIE computing system curriculum consists of information equipment, operating systems, and information and communication fields, and covers basic understanding and principles of computer science. The role of the teacher is important to achieve the curriculum achievement standards. Therefore, we examined the factors affecting the teaching capacity of the KAIE computing system curriculum. The results of this study show that the teaching methods of teachers through the literacy of information and communication technology have a statistically significant effect on the teaching competency of the computing system curriculum. Also, male teachers perceived higher perceived factors than female teachers. The differences in teaching competency between teacher groups of less than 5 years and less than 5~10 years were significant. Based on these results, it is necessary to develop collaborate SW teaching strategies and mentor - centered training programs that can strengthen ICT and SW professors' competence and encourage participation of low - career teachers and female teachers.

• Journal of The Korean Association of Information Education
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• v.23 no.6
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• pp.561-571
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• 2019

Programming education generally includes problem analysis process, automation through algorithms and programming, and generalization process. It is a good software education method for students in improving computing thinking. However, it was found that beginners had difficulties in understanding instruction usage, writing algorithms, and implementing programming. In this study, we developed a game programming education model and curriculum for programming education of pre-service teachers. The 4E model consisted of empathy, exploration, engagement and evaluation. In addition, it is configured to learn game core elements and core command blocks by each stage. To help the pre-service teachers understand the use of various programming blocks, a three-step teaching and learning method was presented, consisting of example learning, self-game creation, and team-based projects. As a result of applying and verifying the curriculum for 15 weeks, it showed significant results in the 4E model and pre-service teachers' perception of block programming competence and the level of computational thinking on the submitted game project results was also high.

• Journal of The Korean Association of Information Education
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• v.23 no.6
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• pp.573-581
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• 2019

In order for education to be effective, it is necessary to properly evaluate the subjects. In order to increase the effectiveness of SW education, it is necessary to reconstruct the curriculum by analyzing the students' satisfaction with education and refluxing the results. Therefore, this study designed and developed the SW education satisfaction measurement tool to accurately measure students' satisfaction with SW education. The categories and items of satisfaction measurement tools were developed, validity was verified through expert verification and AHP analysis, and final items were selected through preliminary examination. Through this study, we developed a tool to measure the satisfaction of SW education, and it is expected that it can be helpful for meaningful education design.