• Structural Engineering and Mechanics
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• 제73권1호
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• pp.75-82
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• 2020

In this study, the problem of torsion of bars with open cross section surrounded by corrugated boundaries is analyzed. An approximate analytical solution is given using perturbation technique. First, the stress analysis for circular open cross-section for arbitrary opening angle is formulated and the problem is analytically solved. Second, the open cross-section with corrugated cross section is analyzed using perturbation method. First order contributions to the stresses and the torques have been added. The results have been exemplified and compared by considering special examples.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제20권1호
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• pp.117-145
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• 2006

수학 영재들은 타고난 수학적 소질과 적성, 지적인 능력과 창의성을 바탕으로 참신한 과제에 대한 도전적이고 창조적인 호기심을 가지고 있다. 영재아들의 창의적인 사고력을 길러주기 위해서는 다양한 방법으로 문제 해결에 접근하게 하고 전략적 시도를 할 수 있도록 만들어주어야 한다. 이런 관점에서 볼 때 개방적이고 비정형적인 문제를 영재 교육프로그램의 과제로 선정하는 것은 바람직하다 할 수 있다. 본 논문에서는 다양한 유형의 개방형 문제를 구안하고, 이를 토대로 영재 학급에서 학습 활동을 전개한 후, 문제해결 과정에서 영재아들의 수학적 사고 능력의 특성과 문제 해결 전략 사례를 분석하여, 개방형 과제를 활용한 초등학교 영재 수업에 관한 시사점을 얻고자 하였다.

• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3803-3810
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• 2022

OpenMC is a community-driven open-source Monte Carlo neutron and photon transport simulation code. The Weight Window Mesh (WWM) function and an automatic Global Variance Reduction (GVR) method was recently developed and implemented in a developmental branch of OpenMC. This WWM function and GVR method broaden OpenMC's usage in general purposes deep penetration shielding calculations. However, the Local Variance Reduction (LVR) method, which suits the source-detector problem, is still missing in OpenMC. In this work, the Weight Window Generator (WWG) function has been developed and benchmarked for the same branch. This WWG function allows OpenMC to generate the WWM for the source-detector problem on its own. Single-material cases with varying shielding and sources were used to benchmark the WWG function and investigate how to set up the particle histories utilized in WWG-run and WWM-run. Results show that there is a maximum improvement of WWM generated by WWG. Based on the above results, instructions on determining the particle histories utilized in WWG-run and WWM-run for optimal computation efficiency are given and tested with a few multi-material cases. These benchmarks demonstrate the ability of the OpenMC WWG function and the above instructions for the source-detector problem. This developmental branch will be released and merged into the main distribution in the future.

• 한국학교수학회논문집
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• 제10권3호
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• pp.303-322
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• 2007

교과서에서 사용되는 문제는 주로 정형화된 폐쇄형의 문제로 학생의 문제해결력을 육성하거나 학생의 자주적인 학습을 촉구하는데 제한적이다. 본 연구는 문제해결력을 육성하기 위해 개방형 문제를 해결해가는 과정을 폴리아의 문제해결단계를 따라 학생에게 나타나는 학습변화를 관찰하였다. 학생은 문제를 더욱 신중히 읽고 이해하는 과정에서 단순화하였고 계획수립과정에선 처음엔 익숙하지 않았지만 다양한 방법으로 해결하려는 시도와 체계적으로 되돌아보는 인지과정을 나타냈으며, 실행과정에서는 오류를 통한 계획수립의 재시도가 일어나 통제가 향상되는 과정을 보였다. 반성단계는 점검만하는 수준을 벗어나 다른 해결방법을 무엇인지 등의 반성단계의 필요성을 인식하였고 개방형문제의 실생활 적용과 일반화하는 과정을 통해 문제 해결력이 더욱 향상됨을 알 수 있었다.

• 한국수학교육학회지시리즈A:수학교육
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• 제55권2호
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• pp.209-232
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• 2016

This study analyzed the process of steps in a program introducing Renzulli's enrichment triad model and various levels of posing open-ended problems of those who participated in the program for mathematics-gifted elementary students. As results, participants showed their abilities of problem posing related to real life in a program introducing Renzulli's enrichment triad model. From eighteen mathematical responses, gifted students were generally outstanding in terms of producing problems that demonstrated high quality completion, communication, and solvability. Amongst these responses from fifteen open-ended problems, all of which showed that the level of students' ability to devise questions was varied in terms of the problems' openness (varied possible outcomes), complexity, and relevance. Meanwhile, some of them didn't show their ability of composing problem with concepts, principle and rules in complex level. In addition, there are high or very high correlations among factors of mathematical problems themselves as well as open-ended problems themselves, and between mathematical problems and open-ended problems. In particular, factors of mathematical problems such as completion, communication, and solvability showed very high correlation with relevance of the problems' openness perspectives.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제10권3호
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• pp.215-227
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• 2006

After reviewing China's appearance and research on the Math open-ended problems, together with the application of those problems in mathematics test of Shanghai Senior Middle School Entrance Exams (SSMSEE) since 1999, this paper points out the difficulty in establishing an evaluation system for such problem. Through comparative study, the paper gives an operational definition of open-ended problem, and it attempts to establish an evaluation system and non-systematic competence targets that are appropriate to Math open-ended problems. Meanwhile, it describes the performance feature of those targets. By applying the standard international grading system of difficulty, it discusses the elements of difficulty in Math open-ended problems, and puts forward an evaluation as well as a level-of-difficulty forecasting system that is appropriate to the Middle School Entrance Exam.

• 한국가정과교육학회지
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• 제12권3호
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• pp.19-38
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• 2000

This study is about open and secondary level Home Economics Education which is applicable to field and which includes the characteristics, purpose and problems of each open education, secondary education and home economics education. Based on the ideology of open education this study will identify the meaning of openness in terms of Home Economics Education reconstructing meaning purpose, characteristics, curriculum paradigm and curriculum. The instructional model and module which use web, will be presented as the results o the reconstruction works. The open instructional module in Home Economics Education which will be operated on the web is consisted of 1) setting the orientation of curriculum development 2) instructional model development 3) rebuilding the Home Economics Education curriculum 4)development of instructional modules and web-based materials and 5)construction of the web-site. Six instructional module begin with critical/emancipatory curriculum paradigm in open Home Economics Education use module as a unit of class management instead of 1 class, facilitates nest-type integration which is applied from open education keeping the nature of Home Economics Education and focus on practical problem and problem solving through reconceptualization with dialectical perspective on individual, family and society. The practical problem solving model has four steps: Identifying practical problems. Understanding the contexts of problem, Searching for solutions and examining its consequences, Action and evaluation. The web-site has to be developed based on the six instructional module includes those issues : self-identification for reinforcing autonomy and self-esteem, living with family living with friends, autonomous living healthy living and understanding sexuality.

• 아동학회지
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• 제33권2호
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• pp.185-201
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• 2012

The purpose of the present study was to investigate the structural relationships between adolescent problem behaviors and related variables. The subjects of this study consisted of 250 to second graders from a middle school in S city in the Gyeongbuk province of South Korea. The sample variance-covariance matrix was analyzed using AMOS 20.0, and a maximum likelihood minimization function. The results were as follows : First, marital conflict in terms of the father's open communication model indicated both a direct and indirect effect upon adolescent problem behaviors. Marital conflict in terms of the father's problematic communication model revealed an indirect effect upon adolescent problem behaviors also indicated that these behaviors were also mediated by the father's problems communication. Second, a open communication style on the part of the father indicated a partially mediating effect on the relationship between marital conflict and adolescent problem behaviors. The problematic communication model on the part of the father revealed a very clear mediating effect on the relationship between marital conflict and adolescent problem behaviors.

• 산업경영시스템학회지
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• 제33권3호
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• pp.30-39
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• 2010

This paper considers a problem of optimizing torch paths to cut stock plates nested with open contours. For each contour, one of the two ending points is to be selected as a starting point of cutting with the other being the exit point. A torch path is composed of a single depot and a series of starting and ending points of contours to be cut. The torch path optimization problem is shown to be formulated as an extended version of the standard travelling salesman problem. To solve the problem, a hybrid genetic algorithm with the local search of torch paths is proposed. The genetic algorithm is tested for hypothetical problems whose optimal solutions are known in advance due to the special structure of them. The computational results show that the algorithm generates very near optimal solutions for most cases of the test problems, which verifies the validity of the algorithms.

• 충청수학회지
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• 제35권1호
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• pp.33-37
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• 2022

In this short note, we prove an open problem for the interval (-∞, ∞), related to a reverse trigonometric Masjed-Jamei inequality presented in [2] and establish a new inequality of a similar kind.