• Journal of KIISE:Software and Applications
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• v.26 no.9
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• pp.1095-1104
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• 1999

객체지향 시스템의 개발은 클래스를 통해서 이루어진다. 즉, 문제 영역에 존재하는 중요한 대상 또는 개념을 클래스로 모델링하고, 이로부터 생성된 객체들 사이의 메시지 교환을 통해서 시스템은 구축된다. 또한, 클래스는 정보 은닉을 제공함으로써, 객체지향 시스템의 재사용성과 유지보수성에 상당한 기여를 한다. 그러나, 설계 단계에서 실세계의 대상을 부적절하게 모델링하거나, 또는 유지보수 단계에서 클래스에 무분별한 변경을 가하는 경우 클래스의 품질은 악화될 수 있고, 이는 결국 시스템을 유지보수 하거나 확장하는데 상당한 장애를 초래한다.응집도는 모듈의 구성 요소들 사이의 연관성 정도를 나타내는 척도로서 전통적으로 모듈의 품질을 평가하기 위한 기준으로 사용되어 왔다. 이 논문에서는 클래스의 품질을 평가하는 방법으로서의 클래스 응집도를 제안한다. 즉, 클래스가 실세계의 대상을 적절하게 모델링한다면, 그 구성요소들 사이에 밀접한 관련이 있고 결국 높은 응집도를 가지게 될 것이다. 반대로 실세계의 대상에 대한 적절한 모델이 아니라면, 그 클래스의 구성 요소들 사이에는 밀접한 관련성이 없을 것이고 따라서 낮은 응집도를 보일 것이다.Abstract Object-oriented systems are developed by means of classes; that is, classes captures the essential entities or concepts in the problem domain, and the system is embodied by the interactions of objects instantiated from the classes. In addition to the basic units of object-oriented systems, classes serves as the units of encapsulation, which considerably promote the modifiability and the extensibility of them. However, improper modeling in the design phase or uncontrolled changes during the maintenance phase can degrade the quality of classes, which leads to systems cumbersome to maintain and extend.Cohesion refers to the degree of connectivity among the elements of a single module, and is being used as a factor which characterizes the quality of a module. In this paper, we propose a new cohesion metric for assessing the quality of classes. If a class captures properly the essential features of objects, the members of the class surely have strong relationship among them. On the contrary, the poor relationship among class members can indicate that the class is not a proper model of objects.

• Journal of Korean Elementary Science Education
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• v.23 no.1
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• pp.50-60
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• 2004

The purpose of this study was to define teachers' learning motivation strategies and students' responses by analyzing science classes and interviews. The subjects were first grade and sixth grade teachers and students of an elementary school. The analysis tools are based on Keller's ARCS theory. The differences of teachers' motivation strategies were analyzed by grades and teachers' and students' backgrounds. The interviewers were composed of three teachers and three students of first grade, and three teachers and three students of sixth grade. The data were collected by recording of the classes using tape recorders, video cameras, and notebooks written by researchers. The results are as follows. First, teachers had their own styles of teaching strategies in their classes. Especially teachers' teaching backgrounds affected on the teachers' instructional strategies. The teachers who had long teaching experiences of lower grade students used to show a lot of attention strategies. While the teachers with long teaching experiences of higher grade students used to show few learning motivation strategies. Especially, sixth grade teachers used to show fewer confidence strategies than first grade teachers. Second, all of the teachers used to show few satisfaction strategies commonly in all the classes observed. Third, the students' recognition of the motivation strategies were not different according to their conceptions or activities of the classes. Commonly first grade students focused on the attention strategies, while sixth grade students focused on negative motivation strategies. Fourth, the teachers who believed that students need detail guidance and control recognized the needs of satisfaction strategies by students' autonomous activities after observing video tapes of other teachers' classes.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.1
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• pp.99-109
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• 2014

The purpose of this study was to obtain consensus from the expert community on the aims of Elementary Science Classes for the Gifted(ESCG) and teaching professionalism of Elementary Science Teachers for the Gifted(ESTG). For the delphi study, nineteen experts were consulted with open-ended and closed questions. Delphi research was conducted a total of 3 times. The Delphi survey was done by e-mail. The experts can express their opinions freely during the research. The results of this study were as follows : First, there were six aims for ESCG. The six aims of ESCG are scientific inquiry ability growth, creative problem solving ability growth, primary science gifted's giftedness development, the future science-talented-children training, the growth of attitudes toward science, scientific attitudes growth. Second, there were four teaching professionalism about teaching professionalism of ESTG. Four teaching professionalism are understanding the characteristics of primary science gifted, the ability to understand and apply the learning methods suitable for primary science gifted education, professional knowledge and ability to understand the science curriculum, the ability to develop and apply primary science education programs.

• Journal of Korean Elementary Science Education
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• v.34 no.4
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• pp.372-381
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• 2015

Mathematics and science are very closely related. Among the science areas, physic is strongly linked with mathematics. As the related mathematics skills were alloted later than the science contents in the national curriculum, students often suffer from science classes. Accordingly, an opinion have been claimed to teach the related mathematics skills prior to the science classes. However, it would be hard to arrange all science and mathematics contents in order. Instead of that, in this research, we taught students mathematics contents that are crucial for learning speed through science classes. We called that teaching strategy an integrated science and mathematics class. Then, we examined students' achievement in science as well as skills of mathematics to know the effectiveness of the strategy. We found that the average mathematics score of the whole class went up meaningfully. We also found that their science achievement was above than basic level. Moreover, the homeroom teacher of the students observed 3 aspects which showed the students were better than previous students. Finally, we divided the students into 4 groups by their science and mathematics achievement score and interviewed each group. As a result, we knew that interesting and confidence in science and mathematics quite exerted influence on their achievement.

• Journal of Korean Elementary Science Education
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• v.17 no.2
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• pp.91-101
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• 1998

The purpose of this study was to find out how to be pursued elementary teachers' science instruction according to their understanding toward science. Sixty elementary teachers were involved in the questionnaire, investigating understanding on the nature of science and the science teaching. Two elementary teachers' science classes are observed. Their instructional objectives were analyzed. And their understanding toward science was measured. Teacher A had consistent modern philosophical views of science on the nature of science and science teaching, and teacher B had not consistency Klopfer's science educational objectives category was used to analyse instructional objective. The ideal proportions of the instructional objectives of the observed classes were established from science education specialist group. You ideality index was calculated. You ideality index indicate how far from the ideal proportions of the instructional objectives the observed instruction is. Relative proportions of instructional objectives appeared in science classes were compared with ideal instructional objectives. Instructional objectives containing the modem views appearing classes observed were compared according to teachers' understanding toward science. As results, teachers' understanding toward science showed lack of consistency, which is consisted of modern philosophical view of science on science teaching: modem and classical philosophical view of science on nature of science. Teacher A's instruction was approached more closely to the ideal proportions of the instructional objectives, showing fewer You ideality index. Instructional objectives containing the modern views are more appeared and closer to ideal proportions in teacher A's classes than in teacher B's. A teacher having modern understanding on nature of science would instruct science with modern scientific philosophical perspectives. Therefore teacher preparation programs should include more contents about modern philosophical understanding on the nature of science.

• Journal of The Korean Association For Science Education
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• v.31 no.2
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• pp.239-255
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• 2011

As a case study on the use of coteaching in science instruction for science-gifted elementary students, this paper analyzed the characteristics of coteaching science instruction for science-gifted elementary students by plan, performance, and reflection-evaluation stages of the classes. To do this, we observed two teachers' coteaching science instruction for science-gifted elementary students during twelve classes and analyzed the taped videos, their journals, and the transcripts for in-depth interviews with them. The results indicated that the characteristics of the coteaching science instruction, in the planning stage of the classes, showed improvement in the quality of the sciencegifted education programs, the reduction of the psychological burdens of developing the programs, and some efficiency loss due to the joint preparation of the classes. The characteristics in the performance stage of the classes include the seamless progression of the classes through the division of roles, the increase of the students' opportunity to explore, the supplement of the teachers' inadequate descriptions and the overlooked contents, the increase of the interaction between teachers and students and/or the interaction among students, the reduction of the risk of accidents in experiments, and the reduction of the responsibility for teaching. Finally, the characteristics in the reflectionevaluation stage of the classes could be attributed to the diversity of the evaluation viewpoints, the increase of the learning opportunities to develop the teaching professionalism, and the increase of the fear for assessing my own classes.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.2
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• pp.192-202
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• 2014

The purpose of this study was to examine the effects of science lessons using mind mapping on creativity and academic achievement in science. The subjects of this study were fifth-grade students selected from four classes of an elementary school located in Busan. For ten weeks, the experimental group of 40 students were taught using the mind mapping technique. The comparative group, also of 40 students, was taught in normal classes which used a standard text-book. Children were given a test on science processing skills and academic achievement in science to measure the effects of mind mapping. The Likert scales were used to gather student's feedback on creativity and academic achievement in science. Through these procedures, the following results were obtained: First, mind mapping had a greater effect on science processing skills than the normal classes, where a text-book was used. Second, mind mapping was effective in improving the student's academic achievements in science at a greater level than the normal classes where a text-book was used. Third, after viewing results of the Student Recognition Investigation, we found that the students showed a higher level of interest in science lessons that used mind mapping, and were better able to understand the scientific theories. As a result, the elementary science class with mind mapping developed greater science processing skills and saw higher academic achievement in science. We conclude that science classes that use mind mapping have the potential to develop better science processing skills and improve academic achievement in science.

• Journal of Science Education
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• v.47 no.1
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• pp.88-106
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• 2023

This study aims to investigate the disparity between the teacher's perception of student-centered inquiry classes and the actual implementation of such practices. Specifically, we compared an elementary science teacher's self-perception of her science lessons with the observers' evaluation using the Reformed Teaching Observation Protocol (RTOP) of the "Temperature and Heat" unit. Research data were collected through classroom teaching survey, interview, and science lessons video which were analyzed using the RTOP. As a result of the study, the teacher recognized that she was practicing inquiry-oriented/student-centered classes, but the results judged by the RTOP score were found to be transitional/student-affected classes by a slight difference. Teacher H planned and practiced classes based on a high understanding and content knowledge of the curriculum and created a science classroom culture that promotes active interaction among students as well as students and teachers. However, teacher-led aspects were still emphasized in teaching design and implementation, and the project theme and content were inappropriate to improve the quality of students' science inquiry experience. In the end, the slight difference between teacher's perception of inquiry-oriented/student-centered classes and actual implementation is related to how student-centered "lesson design" is and how to plan and implement classes supported by "procedural knowledge" for students' experience in the science inquiry process. These results indicate that the teacher's self-evaluation alone is not enough to determine whether the teacher's intentions and efforts are actually being implemented, and that it is necessary to conduct objective analysis, evaluation, and discuss the results of science classes by the external observers.

• Journal of Science Education
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• v.42 no.2
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• pp.230-241
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• 2018

This study was conducted to see how science classes using astronomical observations software could affect elementary students' scientific learning motivations and academic achievements. For this, 24 sixth graders of G Elementary School were designated as experimental groups to provide classes in which astronomical observation software was used. The experimental treatment period was 4 weeks and the results were as follows. First, elementary science classes that used astronomical observation software were effective in boosting scientific learning motivation. Second, elementary science classes that used astronomical observation software were effective in enhancing academic achievements. From these study results, we could confirm that elementary science classes that used astronomical observation software were effective for elementary school students' motivation and academic achievements.

• Journal of Korean Elementary Science Education
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• v.29 no.4
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• pp.427-440
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• 2010

The purpose of this study is to develop a science writing teaching strategy, and to apply it to the fourth-graders in elementary science classes. We examined its effect on their motivation, attitude, and understanding of science concept. For the research fourth grade children were grouped into three classes: an experimental class A of 27 children, an experimental class B of 24 and a comparative class of 27. All of them are from H elementary school in Seoul, Korea. Experimental class A learned science writing with a newly developed strategy while experimental class B learned science writing in a traditional method. Comparative class did not learn science writing. As a result, class A showed positive changes on students' science motivation, attitude, and understanding of science concept. In addition, class B with even one science writing task for a chapter had higher achievement in the understanding of science concept than the comparative class had.