• Journal of Institute of Control, Robotics and Systems
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• v.6 no.3
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• pp.329-337
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• 2000

This study describes a pressure tracking control of hydroforming process which is used for precision forming of sheet metals. The hydroforming operation is performed in the high-pressure chamber strictly controlled by pressure control valve and by the upward motion of a punch moving at a constant speed, The pressure tracking control is very difficult to design and often does not guarantee satisfactory performances be-cause of the punch motion and the nonlinearities and uncertainties of the hydraulic components. To account for these nonlinearities and uncertainties of the process and iterative learning controller is proposed using Cerebellar Model Arithmetic Computer (CMAC). The experimental results show that the proposed learning control is superior to any fixed gain controller in the sense that it enables the system to do the same work more effectively as the number of operation increases. In addition reardless of the uncertainties and nonlinearities of the form-ing process dynamics it can be effectively applied with little a priori knowledge abuot the process.

• Journal of the Korea Society of Computer and Information
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• v.23 no.2
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• pp.117-123
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• 2018

This article is to investigate the possibility that project-based classes introducing mobile phones can replace the monotony of traditional classes led by teachers as well as they can encourage students to take active part in the classes to some extent. The students in groups choose a genre for their own video projects (e.g., movie, drama, news, documentary, and commercial) and produce the video contents using a mobile phone for presentation made at the end of a semester. In the sense that the students are allowed to do video-based mobile phone projects, they can work independently outside of class, where time and space are more flexible and students are free from the anxiety of speaking or acting in front of an audience. A mobile phone project consists of around five stages done both in and outside of the classroom. All of these stages can be graded independently, including genre selection, drafting of scripts, peer review and revision, rehearsals, and presentation of the video. Feedback is given to students. After the presentation, students filled out a survey questionnaire sheet devised to analyze students' responses toward preferences and level of difficulty of the project activity. Finally, proposals are made for introduction of a better mobile phone-based project classes.

• Journal of the Earthquake Engineering Society of Korea
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• v.27 no.4
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• pp.171-180
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• 2023

This study proposed a seismic reinforcement of RC columns with non-seismic details, a fiber reinforcement method of aramid sheets and MLCP (high elasticity aromatic polyester fiber material) with different characteristics, and 4 full-size column specimens and conducted experiments. The results show that a non-seismic specimen (RC-Orig) rapidly lost its load-bearing capacity after reaching the maximum load, and shear failure occurred. The RC column reinforced with three types of aramid did not show an apparent increase in strength compared to the unreinforced specimen but showed a ductile behavior supporting the load while receiving a lateral displacement at least 1.57 to 1.95 times higher than the unreinforced specimen. The fracture mode of the specimen, according to the application of lateral load, also changed from shear to ductile fracture through aramid-based reinforcement. In addition, when examining the energy dissipation ability of the reinforced specimens, a ductile behavior dissipating seismic energy performed 4 times greater and more stably than the existing specimens.

• Journal of the Korea Convergence Society
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• v.11 no.8
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• pp.33-38
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• 2020

Modern society needs to think in new directions and solve problems by grafting problems from diverse fields with computers. Abstraction and automation of various problems using computing technology with your own ideas is called computational thinking. In this paper, we analyze how to diagnose and improve knowledge information based on computational thinking through the process of presenting a variety of problems in programming education situations and finding several problem-solving methods to solve them. To pretest the learners, they were diagnosed using a measurement sheet and a LightBot. By determining the correlation between the evaluation results and LightBot results, the learners' current knowledge statuses were checked, and the correlation between the evaluation results and the LightBot results, based on what was taught according to the problem-solving learning technique, was analyzed according to the proposed technique. The analysis of the group average score of the learners showed that the learning effect was significant. If the method of deriving and improving knowledge based on computational thinking ability for solving the problem proposed in this paper is applied to software education, it will induce student interest, thereby increasing the learning effect.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.3
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• pp.327-337
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• 2014

In this research, a subject substitute STEAM program was developed in context of a trend of STEAM education and a new science contents in a 2009 revised curriculum, which can replace the 2009 revised curriculum contents of 'Sound' unit in the third and the fourth grade. The developed program was taught to the 4th graders in a field. After applying the program, how students acknowledge the subject substitute STEAM program was analyzed through questionnaire. The research results were as follows. First, the subject substitute STEAM program of 3 sub programs was developed with centered around 'sound' unit for 4th graders. Second, students made a positive estimation of the STEAM program because of various activities and learning subject related to daily life. Third, they considered difficult term, necessary craft skills in creative design, understanding scientific principle and a lot of necessary time as difficulties of the STEAM program. And they also recognized that making stuff activity and learning aid material like activity sheet, picture and video helped to understand a lesson. Lastly, students had a positive thinking or negative thinking about STEAM program before they learn. But after learning the STEAM program, all of them showed their positive attitude to the STEAM program.

• Journal of Elementary Mathematics Education in Korea
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• v.22 no.1
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• pp.93-114
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• 2018

The purpose of this study was to analyze mathematical the effects of problem posing activities on students' characteristics toward mathematics to encourage active learning. We will also examine various examples of the characteristics of the problems made by students with different mathematical characteristics. We chose one 6th grade group to conduct this research. From the results of this study, we obtained the following conclusions. First, problem posing activities are effective in improving students' mathematical interest and confidence, value recognition. Second, Students with different mathematical characteristics showed different results in problem posing activities. We confirmed the effectiveness of problem posing activities on students' positive characteristics of mathematics. In this regard, we were able to confirm examples of various problems that students made. In the future, we would like to propose generalization by conducting research on students of various school ages.

• Journal of the Korean Society of Earth Science Education
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• v.1 no.1
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• pp.1-13
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• 2008

The purpose of this research is to accomplish the goal of science education based in the seventh science course of study by suggesting the plan for development of executable method in the learning process of Earth Science education and establishing a practical model to evaluate its achievement. Furthermore, the idea of this research is to recognize a way of using and consideration at practical use of the model. Since the purpose of the educational evaluation is to maximize the efficiency of school studying, there are some negative aspects in our current method of evaluation to achieve the purpose. New system has been introduced into the educational evaluation to resolve such a critical issue. Despite some positive aspects in the system, it could not be escaped from the multiple choice and pens examination. This could be caused by in various limitations, especially the insufficiency of teachers' awareness and the data about the Performance assessment. This research is to develop and use the practical model for the Performance assessment in consideration of current educational circumstances of Junior and High school. The model of the Performance assessment in this research is to sufficiently evaluate student's ability and skill in the learning process of Earth Science education. Hence, it is dedicated to the education for human being and improve quality in the learning process of the Earth Science education among the modern society, which is characterized globalization and information. Furthermore, it may promote the growth of various character of students and increase creativity and skill for the problem solving.

• Journal of Elementary Mathematics Education in Korea
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• v.17 no.1
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• pp.165-184
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• 2013

In order to utilize Sphinx Puzzle in shape education or deductive reasoning, a lesson employing Dienes' six-stage theory of learning mathematics was structured to be applied to students of 6th grade of elementary school. 4 students of 6th grade of elementary school, the researcher's current workplace, were selected as subjects. The academic achievement level of 4 subjects range across top to medium, who are generally enthusiastic and hardworking in learning activities. During the 3 lessons, the researcher played role as the guide and observer, recorded observation, collected activity sheet written by subjects, presentation materials, essays on the experience, interview data, and analyzed them to the detail. A task of finding every possible triangle out of pieces of Sphinx Puzzle was given, and until 6 steps of formalization was set, students' attitude to find a better way of mathematical deduction, especially that of operational thinking and deductive thinking, was carefully observed and analyzed.

• The Journal of Korean Association of Computer Education
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• v.6 no.4
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• pp.85-93
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• 2003

This paper proposes an item based learning system using e-mail in order to motivate learners effectively and avoid the bottleneck problem under highly competitive access situations such as the traditional web based learning. The proposed system has th ree features as follows: first, through e-mail, a learner receives test items depending on his/her level, submit an answer sheet, and then identify an assessment with help messages. Secondly, on the web, an instructor easily constructs item database without any other tools and monitors the status of each learner by identifying the learners' record. Finally, an easy-to-use interaction mechanism enhances the inter-activity between learners and instructors, and the usability of Q&A(Question and Answer) service by incorporating e-mail into the web bulletin board.

• The Journal of the Acoustical Society of Korea
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• v.43 no.2
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• pp.207-213
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• 2024

In this paper, we study how to improve the performance of a machine learning-based automatic music transcription model by adding musical information to the input data. Where, the added musical information is information on the number of pitches that occur in each time frame, and which is obtained by counting the number of notes activated in the answer sheet. The obtained information on the number of pitches was used by concatenating it to the log mel-spectrogram, which is the input of the existing model. In this study, we use the automatic music transcription model included the four types of block predicting four types of musical information, we demonstrate that a simple method of adding pitch number information corresponding to the music information to be predicted by each block to the existing input was helpful in training the model. In order to evaluate the performance improvement proceed with an experiment using MIDI Aligned Piano Sounds (MAPS) data, as a result, when using all pitch number information, performance improvement was confirmed by 9.7 % in frame-based F1 score and 21.8 % in note-based F1 score including offset.