• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.97-113
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• 2004

In this paper we shall study moving boundary problems, and we introduce an approach for solving a wide range of them by using calculus of variations and optimization. First, we transform the problem equivalently into an optimal control problem by defining an objective function and artificial control functions. By using measure theory, the new problem is modified into one consisting of the minimization of a linear functional over a set of Radon measures; then we obtain an optimal measure which is then approximated by a finite combination of atomic measures and the problem converted to an infinite-dimensional linear programming. We approximate the infinite linear programming to a finite-dimensional linear programming. Then by using the solution of the latter problem we obtain an approximate solution for moving boundary function on specific time. Furthermore, we show the path of moving boundary from initial state to final state.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.713-716
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• 1996

Managers are constantly facing problems. Some problems are treated with special connotation. Others are solved as a daily routine. While other problems disppear into the realm of oblivion without even recognized by managers. Some of the unrecognized or overlooked problems may cause a serious failure. It is also likely that there is a better solution approach even though we have been using a generally accepted method. Problem identification is a neglected area by researchers and managers, although they are facing problems everday. This paper provides a review of the theories pertained to problem definition and problem identification as the beginning stage of the problem solving process. Based on these theories, we provide an expert system which can assist managers for a better problem solving. Knowledge base for problem identification and recommaendation of tools for the problem solving is the key ingredient of the expert system.

• Journal of the Korean earth science society
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• v.23 no.2
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• pp.147-153
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• 2002

Reasonable and reliable assessment method is one of the most important issues in science education, Partial credits method is an effective tool for assessing students' science inquiry problem solving. The purposes of this study were to classify the Problem solving types based on the analysis of the thinking Process, and how much the related science concept and the science process skills were used in solving science inquiry problems, and to describe the possibility and rationality of the assessment method that gives partial credit 128 high school seniors were selected and their answers were analyzed to identify science concepts they used to solve each problem, and the result was used as the criterion in the scientific concept test development. Also, to study the science inquiry problem solving type, 152 high school seniors were selected, and protocols were made from audio-taped data of their problem solving process through a think-aloud method and retrospective interviews. In order to get a raw data needed in statistical comparison of reliability, discrimination and the difficulty of the test and the production of the regression equation that determines the ratio of partial credit, 640 students were selected and they were given a science inquiry problem test, a science process skills test, and a scientific concept test. Research result suggested it is more reasonable and reliable to switch to the assessment method that applies partial credit to different problem solving types based on the analysis of the thinking process in problem solving process, instead of the dichotomous credit method.

• Journal of IKEEE
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• v.23 no.4
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• pp.1150-1156
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• 2019

This paper explores a model-free value-based approach for solving survival gridworld problem. Survival gridworld problem opens up a challenge involving taking risks to gain better rewards. Classic value-based approach in model-free reinforcement learning assumes minimal risk decisions. The proposed method involves a hybrid on-policy and off-policy updates to experience roll-outs using a modified Q-based update equation that introduces a parametric linear rectifier and motivational discount. The significance of this approach is it allows model-free training of agents that take into account risk factors and motivated exploration to gain better path decisions. Experimentations suggest that the proposed method achieved better exploration and path selection resulting to higher episode scores than classic off-policy and on-policy Q-based updates.

• Korean Journal of Child Studies
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• v.25 no.3
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• pp.1-14
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• 2004

This study focused on the development and application of learning cycle model for promoting children's creativity and problem solving ability. The learning cycle approach consists of four phases : awareness, exploration, investigation, and concept application. The program consists of 20 scientific activities. A total of 70 children participated the 10 week program to examine the effectiveness of this model. The experimental design included a pretest, treatment, and posttest. Results showed that the experimental group children scored significantly higher on the creativity and problem solving tests in the posttest than the control group children.

• Educational Technology International
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• v.6 no.2
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• pp.69-85
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• 2005

The purpose of the article is to address a new instructional approach to a complex engineering course. We design a novel instructional method that combines mobile technology, simulation program, collaborative teamwork, problem-solving process, and a variety of evaluation techniques. We suggested five instructional principles that might be required to change the fundamental educational process by which learning is done. The proposed instructional method is expected to aspire for new perspectives on complex learning environment. Nevertheless we solely began by the research on the development of students' complex problem-solving performance in a complex engineering course, the new instructional method in the article can promote the adoption of new instructional methods and strategies across different knowledge domains. In addition, the instructional method can provide a valuable bridge to acquisition and transfer of problem solving, motivation, and meaning learning.

• Journal of Elementary Mathematics Education in Korea
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• v.14 no.2
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• pp.315-335
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• 2010

The goal of this research was to study the effects of the Mathematical Problem Generating Program on problem solving ability and learning attitude. The experiment was carried out between two classes. One class was applied with the experimental program (treatment group), and the other continued with normal teaching and learning methods (comparative group). In this study, two 5th grade elementary classes participated in Seoul city. In this study, the students were tested their problem solving abilities by the IPSP test and learning attitude by the Korean Education Development Institute (KEDI) before and after use of the program. The collected results were t-tested to find any meaningful changes. The results showed the followings. First, use of the mathematical generating program showed meaningful progressive results in problem solving ability. Second, the students that used the program showed positive results in learning attitude. In conclusion, learning mathematics using the problem generating method helps students deeper understand and solve complex problems. In addition, problem solving abilities can be improved and the attitude towards mathematics can be changed while students are using an active and positive approach in problem solving processes.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.394-401
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• 2003

We consider a PCB grouping problem arising from the electronic industry. Given a surface mounting device, several types of PCBs and a number of component feeders used to assemble the PCBs. the optimization problem is the PCB grouping problem while minimizing setup time of component feeders. We formulate the problem as an Integer programming model and propose a column generation approach to solve the Integer programming formulation. In this approach we decompose the original problem Into master problem and column generation subproblem Starting with a few columns in the master problem. we generate new columns successively by solving subproblem optimally. To solve the subproblem. we use a branrh-and-rut approach. Computational experiments show that our solution approach gives high quality solutions in a reasonable computing time.

• Journal of applied mathematics & informatics
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• v.8 no.1
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• pp.151-164
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• 2001

In this paper, a new approach for finding the approximate solution of the Stokes problem is introduced. In this method the problem is transformed to an equivalent optimization problem. Then, by considering it as a distributed parameter control system, the theory of measure is used to approximate values of pressure are obtained by a finite difference scheme.

• Education of Primary School Mathematics
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• v.17 no.2
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• pp.95-111
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• 2014

The purpose of this study is to determine the relationship between metacognition and math creative problem solving ability. Specific research questions set up according to the purpose of this study are as follows. First, what relation does metacognition has with creative math problem-solving ability of mathematically gifted elementary students? Second, how does each component of metacognition (i.e. metacognitive knowledge, metacognitive regulation, metacognitive experiences) influences the math creative problem solving ability of mathematically gifted elementary students? The present study was conducted with a total of 80 fifth grade mathematically gifted elementary students. For assessment tools, the study used the Math Creative Problem Solving Ability Test and the Metacognition Test. Analyses of collected data involved descriptive statistics, computation of Pearson's product moment correlation coefficient, and multiple regression analysis by using the SPSS Statistics 20. The findings from the study were as follows. First, a great deal of variability between individuals was found in math creative problem solving ability and metacognition even within the group of mathematically gifted elementary students. Second, significant correlation was found between math creative problem solving ability and metacognition. Third, according to multiple regression analysis of math creative problem solving ability by component of metacognition, it was found that metacognitive knowledge is the metacognitive component that relatively has the greatest effect on overall math creative problem-solving ability. Fourth, results indicated that metacognitive knowledge has the greatest effect on fluency and originality among subelements of math creative problem solving ability, while metacognitive regulation has the greatest effect on flexibility. It was found that metacognitive experiences relatively has little effect on math creative problem solving ability. This findings suggests the possibility of metacognitive approach in math gifted curricula and programs for cultivating mathematically gifted students' math creative problem-solving ability.