• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.171-177
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• 2021

In terms of distribution planning, accurate electric load prediction is one of the most important factors. The future load prediction has manually been performed by calculating the maximum electric load considering loads transfer/switching and multiplying it with the load increase rate. In here, the risk of human error is inherent and thus an automated maximum electric load forecasting system is required. Although there are many existing methods and techniques to predict future electric loads, such as regression analysis, many of them have limitations in reflecting the nonlinear characteristics of the electric load and the complexity due to Photovoltaics (PVs), Electric Vehicles (EVs), and etc. This study, therefore, proposes a method of predicting future electric loads on distribution lines by using Machine Learning (ML) method that can reflect the characteristics of these nonlinearities. In addition, predictive models were developed based on actual data collected at KEPCO's existing distribution lines and the adequacy of developed models was verified as well. Also, as the distribution planning has a direct bearing on the investment, and amount of investment has a direct bearing on the maximum electric load, various baseline such as maximum, lowest, median value that can assesses the adequacy and accuracy of proposed ML based electric load prediction methods were suggested.

• 디지털융복합연구
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• 제8권4호
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• pp.151-164
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• 2010

본 연구는 유비쿼터스 생활영어 체험학습장의 학습만족과 관련 있는 변인들 가운데 학습환경, 자신감, 학습흥미, 학습만족간의 연구모형으로 구성하여 이 연구모형의 경로를 분석하여 다음과 같은 결과를 얻었다. 첫째, 연구의 변인들 간에 상관관계를 살펴본 결과 유비쿼터스 생활영어 체험학습장을 이용하는 학습자의 학습환경, 자신감, 학습흥미, 학습만족 간에 상관관계가 있었다. 학습환경과 학습흥미, 학습환경과 학습만족, 자신감과 학습흥미 자신감과 학습만족, 학습흥미와 학습만족 간에 정적상관관계를 가졌다. 둘째, 설정된 요인들 간의 경로를 분석해본 결과, 이론모형이 모형 적합도 지수에 만족하여 경로모델이 도출되었다. 연구모형의 경로는 학습환경${\rightarrow}$자신감의 경로와 학습환경${\rightarrow}$학습흥미의 경로가 유의하였다. 그리고 학습환경${\rightarrow}$학습만족의 경로, 자신감${\rightarrow}$학습만족의 경로와 학습흥미${\rightarrow}$학습만족의 경로가 유의했다. 마지막으로, 유비쿼터스 생활영어 체험학습장의 학습환경은 학습자의 학습만족에 직접영향을 미치는 경로로 나타났다.

• 수산해양교육연구
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• 제26권2호
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• pp.296-307
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• 2014

As an educational trial for pursuit of educational excellence in the disadvantaged gifted, this study was to explore learning styles and task preferences by student's grade and gender. Furthermore, this study sought to present the practical basis to develop programs for disadvantaged gifted students. Total 153 disadvantage gifted students responded items of the Learning Styles Inventory-III and the Task Preferences Scale, which responses were analyzed by student's grade and gender in using MANOVA. As the results, the 1st grade disadvantaged gifted students preferred Direct instruction, Technology, and Learning games to the higher grade level students. There were significant differences in task preferences by students' grade level. The 4th grade disadvantaged gifted students preferred Creative tasks and Difficult tasks more than other grade level students.

• 공학교육연구
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• 제18권4호
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• pp.13-25
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• 2015

The purpose of this study was to investigate structural relationships among engineering self-efficacy, outcome expectation, interest, learning persistence, and career preparation behavior of engineering students. Participants (n=428) completed measures of engineering self-efficacy, outcome expectations, interests, learning persistence, and career preparation behavior. Results from structural equation modeling analysis were found to support the proposed model which included learning persistence and career preparation behavior, influence from engineering self-efficacy, outcome expectations, and interests. In addition, major persistence intention and career preparation behavior of engineering college students are influenced by the direct and indirect effects on engineering self-efficacy, interest, and outcome expectations. The implications of the findings on practice for Korean engineering college students are discussed.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제6권1호
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• pp.1-28
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• 2002

This study explored teachers (n = 219) from northern, central, southern and eastern Taiwan concerning their views about children's learning difficulties, mathematical instruction and school mathematics curricular. Results showed that teachers' mathematics knowledge or their instruction methods had no significant influence on their views of children's learning difficulties. Even though teachers indicated that understanding of abstract mathematical concepts was the most prominent difficulty for children, they tended to employ direct instruction rather than constructive and cooperative problem solving in their teaching. However, teachers' views of children's learning difficulties did influence their instructional practice. Results from in-dept interviews revealed that there were some obstacles that prevented teachers from putting constructiveism perspectives of instruction into teaching practice. Further investigation is needed to develop a better understanding of epistemology and teaming psychology as well as to help teachers create constructive learning situations.

• East Asian mathematical journal
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• 제31권2호
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• pp.245-273
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• 2015

The purpose of this study is to investigate environmental factors that affect mathematics learning of students in multicultural families. For this study, as study subjects, eight elementary school students and one middle school student, who were born and grew up in multicultural families in Korea due to international marriage of Korean father and foreign mother, and their five mothers were selected. To examine factors affecting mathematics learning and interests of students in multicultural families, relationships with parents, friends, and teachers were surveyed, and mathematics attitude test was performed. After conducting one on one interview based on collected questionnaires and results of the attitude test, qualitative data analysis was performed. As a result of survey and interview, positive factors affecting mathematics learning of students in multicultural families included arousing interest in mathematics through mother's mathematics teaching in her mother language and direct teaching, good peer relation, teacher's compliment and encouragement, and lowering the burden of language in accordance with characteristics of mathematics course.

• Journal of Electrical Engineering and Technology
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• 제13권4호
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• pp.1705-1714
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• 2018

This paper develops a novel controller called iterative learning sliding mode (ILSM) to control linear and nonlinear fractional-order systems. This control applies a combination structures of continuous and discontinuous controller, conducts the system output to the desired output and achieve better control performance. This controller is designed in the way to be robust against the external disturbance. It also estimates unknown parameters of fractional-order systems. The proposed controller unlike the conventional iterative learning control for fractional systems does not need to apply direct control input to output of the system. It is shown that the controller perform well in partial and complete observable conditions. Simulation results demonstrate very good performance of the iterative learning sliding mode controller for achieving the desired control objective by increasing the number of iterations in the control loop.

• ETRI Journal
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• 제43권6호
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• pp.1004-1012
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• 2021

The collaboration productively interacting between multi-agents has become an emerging issue in real-world applications. In reinforcement learning, multi-agent environments present challenges beyond tractable issues in single-agent settings. This collaborative environment has the following highly complex attributes: sparse rewards for task completion, limited communications between each other, and only partial observations. In particular, adjustments in an agent's action policy result in a nonstationary environment from the other agent's perspective, which causes high variance in the learned policies and prevents the direct use of reinforcement learning approaches. Unexpected social loafing caused by high dispersion makes it difficult for all agents to succeed in collaborative tasks. Therefore, we address a paradox caused by the social loafing to significantly reduce total returns after a certain timestep of multi-agent reinforcement learning. We further demonstrate that the collaborative paradox in multi-agent environments can be avoided by our proposed effective early stop method leveraging a metric for social loafing.

• 한국수학교육학회지시리즈A:수학교육
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• 제60권4호
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• pp.493-508
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• 2021

본 연구는 중학생이 인식한 학습자 중심 수학수업이 수학자기효능감과 수업참여에 미치는 영향을 분석하였다. 그 결과, 토의토론학습은 수업참여에 직접적인 영향을 미치지는 않았지만 수학자기효능감을 매개하여 간접적인 정적 영향을 미쳤으며, 자기주도학습과 협동학습은 수업참여에 직접적인 영향과 수학자기효능감을 매개하여 간접적인 정적 영향을 미쳤다. 또한 성취 상·하위집단 간 토의토론학습이 수학자기효능감에 미치는 효과, 자기주도학습이 수학자기효능감에 미치는 효과, 그리고 수학자기효능감이 수업참여에 미치는 효과에 있어서 유의한 차이가 나타났다. 이는 학습자 중심 수학수업을 위한 학습의 조력자로서 수학교사의 역할에 의미 있는 시사점을 제시한다.

• 수산해양교육연구
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• 제29권3호
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• pp.909-919
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• 2017

The purpose of this study was to apply the learning clinic program to the maladjusted children to help the cognitive processing style, sense type and learning strategy. The results were as follows. First, the cognitive processing style of low-grade elementary school children is divided into the concept of sequential low-order style, which analyzes information sequentially and consecutively, concrete thinking style that processes real and direct information coming in from outside, and invisible principle or information. The abstract cognitive thinking style improved after the process before the program proceeded. However, There was no meaningful result in the simultaneous processing cognitive style which had excellent intuition and emotion and likes change. Second, the temporal lobe in which the linguistic activity is viewed, heard and spoken in the sensory type, the function of the occipital lobe in which the character or the language is processed is improved, but the function of the parietal lobe in moving and manipulating the body is not significant. Finally, factors that contribute to learning such as sincerity, learning initiative, study method, study habits, and concentration are helpful in learning and school life.