• 한국정보처리학회논문지
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• 제6권4호
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• pp.952-958
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• 1999

본 논문에서는 유전자 알고리즘을 이용하여 퍼지 제어 시스템 설계 방법을 제안한다. 시스템의 성능 평가는 rise-time, settling time 그리고 overshoot와 같은 성능 매개변수를 이용하였다. 제안한 방법은 root-locus 방법을 사용한 제어 시스템과 비교하였다. 기존 제어 시스템은 제어기 설계시 수학적인 처리가 필요하다. 하지만 유전자 알고리즘을 이용한 제어기 설계는 수학적인 모델링을 할 필요가 없다. 그리고 일반적으로 시스템의 비선형 정도는 탐색에 의해서만 알수 있는 성질의 것이므로 본 논문에서는 최적의 탐색 알고리즘으로 널리 인정되고 있는 유전자 알고리즘을 사용하여 전역적인 규칙 공간을 탐색한 후 이를 바탕으로 퍼지 제어기를 완성한다. 제안된 제어 시스템의 효율성은 타스크 트래킹 위치 제어 시스템을 사용하여 안정, 불안정 시스템에서 컴퓨터 모의 실험을 통해서 입증된다.

• 한국학교수학회논문집
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• 제24권2호
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• pp.191-216
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• 2021

본 연구는 2015 개정 수학과 교육과정에 따른 <확률과 통계> 교과서의 통계적 추정 단원에서, 통계적 문제해결과정과 함께 통계적 소양이 어떻게 구현되는가를 분석하였다. 문헌 연구를 통해 통계적 소양의 성장에 기여하는 요소로서 '맥락', '변이성', '수학적·통계적 지식', '공학 도구의 활용', '비판적 태도', '의사소통'을 도출하여 통계적 문제해결과정에 따른 분석 관점을 설정하고, 이를 코드화하여 개발한 분석틀을 토대로 교과서 분석을 실시하였다. 통계적 문제해결과정의 관점에서 분석결과 '자료 분석'에 해당하는 과제가 많이 제시되어 있었고 '결과 해석', '문제 설정'과 관련한 과제가 부족하였다. 통계적 소양의 요소별 반영에 관한 분석 결과 '수학적·통계적 지식'을 요구하는 과제가 가장 많았으며, '비판적 태도', '공학 도구 활용'은 거의 다루어지지 않고 있었다. 이러한 교과서 분석결과를 바탕으로 통계적 소양의 함양 교육을 위한 교육과정 개선 및 교과서 개발에 대한 시사점을 제시하였다.

• 한국수학교육학회지시리즈A:수학교육
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• 제58권1호
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• pp.41-54
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• 2019

The purpose of this study was to examine the effects of career identity on learning persistence and academic achievement, and mediating effect of utility value. To examine the effect of mediating role of utility value, we divided utility value into two types, utility value of daily matters and utility value of career. This study was conducted on 228 senior students in high school, to investigate relations among career identity, utility value, learning persistence and academic achievement in mathematics, by using the structural equation model. The results are as follows. First, career identity positively predicted learning persistence in mathematics. Second, career identity positively predicted the utility value of daily matters and career. Third, both type of utility value in mathematics positively predicted learning persistence in mathematics. Fourth, the utility value of daily matters and career, in mathematics subjects, showed differential predictability toward learning persistence and academic achievement. Both type of utility value in mathematics positively predicted learning persistence, but showed differential predictability toward learning academic achievement. Specifically, the utility value of daily matters in the near future did not predict the academic achievement, but the utility value of career in the distant future positively predicted the academic achievement. Fifth, the utility value was found to play a mediating role in the relationship between career identity and learning persistence. Based on the results of this study, implications for mathematics education were discussed.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제25권4호
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• pp.433-457
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• 2022

본 연구에서는 초등학교 교사 15명과 교사 교육자 1인으로 구성된 교사 공동체에서 전체 논의와 학년별 논의를 바탕으로 Smith와 Stein(2018)이 제안한 5가지 관행을 적용하여 초등 수학 수업을 개선하고자 노력한 사례를 분석하였다. 연구 결과, 교사 공동체를 중심으로 한 활동을 통하여 대부분의 학년에서 관행이 매우 잘 실행되는 4수준을 유지하거나 관행의 수준이 점차 상승하는 것을 확인할 수 있었다. 관행별로 살펴보면, 목표 설정, 과제 선정, 예상하기, 선정하기의 경우 대부분의 학년에서 실행 수준이 상승하거나 4수준으로 유지되었으나, 계열짓기와 연결하기의 경우 실행 수준의 상승, 하락, 유지가 다양하게 드러났다. 또한 점검하기의 경우 잘못 적용하는 요소를 포함하는 2수준을 유지하거나 기껏해야 수준 상승 후 하락하는 경우가 있었다. 이와 같은 연구 결과를 토대로 교사 공동체를 중심으로 효과적인 수학적 논의를 실현하기 위한 시사점을 제언하였다.

• 대한수학교육학회지:수학교육학연구
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• 제8권1호
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• pp.251-568
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• 1998

It is the purpose of this study that is to examine the practice and awareness on the use of calculator and to find the method to utilize the calculator as the tool in elementary school mathematics. Recently, it is recommendes strongly to use technical tools such as calculator and computer for the quiltative development on mathematics education. But we prohibite the usage of calculator and do not have the policy to use the calculator in our country because we have little understanding about it. The following direction for educational development is focused not on the repeat learning through the written computation, but on the ability for students to choose an operator and to perform the task with their own objects and strategies. By using the calculator, We can do the followings : 1)to help the mathematical concept develop, 2)to expand the computational ability from written computation to both mental computation and computational estimation, 3)to use the practical value in the problem situation, 4)to reinforce the problem solving, 5)to obtain the interest and the confedence on mathematics. Therefore, we must endevor actively for the broad usage of calculator in the mathematics class.

• Computers and Concrete
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• 제25권6호
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• pp.565-574
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• 2020

Over the years, several machine learning approaches have been proposed and utilized to create a prediction model for the high-performance concrete (HPC) slump flow. Despite HPC is a highly complex material, predicting its pattern is a rather ambitious process. Hence, choosing and applying the correct method remain a crucial task. Like some other problems, prediction of HPC slump flow suffers from abnormal attributes which might both have an influence on prediction accuracy and increases variance. In recent years, different studies are proposed to optimize the prediction accuracy for HPC slump flow. However, more state-of-the-art regression algorithms can be implemented to create a better model. This study focuses on several methods with different mathematical backgrounds to get the best possible results. Four well-known algorithms Support Vector Regression, M5P Trees, Random Forest, and MLPReg are implemented with optimum parameters as base learners. Also, redundant features are examined to better understand both how ingredients influence on prediction models and whether possible to achieve acceptable results with a few components. Based on the findings, the MLPReg algorithm with optimum parameters gives better results than others in terms of commonly used statistical error evaluation metrics. Besides, chosen algorithms can give rather accurate results using just a few attributes of a slump flow dataset.

• 대한수학교육학회지:학교수학
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• 제19권2호
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• pp.405-421
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• 2017

본 연구는 초등 교사교육의 현장 연계성을 강화하기 위한 방안으로서 예비교사와 현직교사의 협력을 시도하였다. 예비교사와 현직교사의 협력이 예비교사교육의 실질적인 대안으로 자리 잡기 위해서는 구체적인 사례와 효과가 제시될 필요가 있다. 이에 따라 본 연구는 현직교사와 예비교사가 협력하여 수학 수업 과제를 개발하는 사례를 구체적으로 제시하고, 그 과정에서 예비교사와 현직교사의 역할을 분석하여 협력의 가능성을 파악하였다. 연구 결과, 예비교사와 현직교사는 과제를 개발하는 과정에서 학생의 수준과 흥미를 고려하거나 수학적 내용을 고려하였다. 각 주체는 학생과 내용의 상호작용 측면을 직접적으로 고려하지는 않았지만, 각자의 역할이 서로에게 영향을 주면서 과제가 개선되는 모습을 확인할 수 있었다.

• Smart Structures and Systems
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• 제15권2호
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• pp.409-424
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• 2015

Structural nonlinearity is a common phenomenon encountered in engineering structures under severe dynamic loading. It is necessary to localize and identify structural nonlinearities using structural dynamic measurements for damage detection and performance evaluation of structures. However, identification of nonlinear structural systems is a difficult task, especially when proper mathematical models for structural nonlinear behaviors are not available. In prior studies on nonparametric identification of nonlinear structures, the locations of structural nonlinearities are usually assumed known and all structural responses are measured. In this paper, an identification algorithm is proposed for locating and identifying model-free structural nonlinearities and systems using incomplete measurements of structural responses. First, equivalent linear structural systems are established and identified by the extended Kalman filter (EKF). The locations of structural nonlinearities are identified. Then, the model-free structural nonlinear restoring forces are approximated by power series polynomial models. The unscented Kalman filter (UKF) is utilized to identify structural nonlinear restoring forces and structural systems. Both numerical simulation examples and experimental test of a multi-story shear building with a MR damper are used to validate the proposed algorithm.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.894-902
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• 2003

Prebiotics (peptides, N-acetyglucoamine, fructo-oligosaccharides, isomalto-oligosaccharides and galactooligosaccharides) were added to skim milk in order to improve the growth rate of contained Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium longum and Bifidobacterium bifidum. The purpose of this research was to study the potential synergy between probiotics and prebiotics when present in milk, and to apply modern optimization techniques to obtain optimal design and performance for the growth rate of the probiotics using a response surface-modeling technique. To carry out response surface modeling, the regression method was performed on experimental results to build mathematical models. The models were then formulated as an objective function in an optimization problem that was consequently optimized using a genetic algorithm and sequential quadratic programming approach to obtain the maximum growth rate of the probiotics. The results showed that the quadratic models appeared to have the most accurate response surface fit. Both SQP and GA were able to identify the optimal combination of prebiotics to stimulate the growth of probiotics in milk. Comparing both methods, SQP appeared to be more efficient than GA at such a task.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.643-646
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• 2006

This paper addresses the approach to extract linear features from satellite imagery using an efficient segmentation method. The extraction of linear features from satellite images has been the main concern of many scientists. There is a need to develop a more capable and cost effective method for the Iranian map revision tasks. The conventional approaches for producing, maintaining, and updating GIS map are time consuming and costly process. Hence, this research is intended to investigate how to obtain linear features from SPOT satellite imagery. This was accomplished using a discontinuity-based segmentation technique that encompasses four stages: low level bottom-up, middle level bottom-up, edge thinning and accuracy assessment. The first step is geometric correction and noise removal using suitable operator. The second step includes choosing the appropriate edge detection method, finding its proper threshold and designing the built-up image. The next step is implementing edge thinning method using mathematical morphology technique. Lastly, the geometric accuracy assessment task for feature extraction as well as an assessment for the built-up result has been carried out. Overall, this approach has been applied successfully for linear feature extraction from SPOT image.