• Physical Therapy Korea
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• v.19 no.1
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• pp.86-93
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• 2012

The purpose of this study was to assess the feasibility of task-oriented arm training for chronic hemiparetic stroke patients. The experimental design in this study was the pre-test and post-test with control group for 4-week intervention. Thirty patients with chronic hemiparetic stroke were recruited from 2 rehabilitation units. The subjects were divided randomly into experimental and control groups. The experimental group conducted task-oriented approach, involving 3 subparts of upper extremity activities, and the control group involved in the general upper extremity exercises. Functional movements of the upper extremities were assessed using clinical measures, including the Fugl-Meyer Assessment-Upper Extremity Section, Box and Block Test, and Action Research Arm Test. The score of Fugl-Meyer Assessment showed greater increases in the experimental group than in the control group after training. The improvement in Box and Block Test between pre-test and post-test measurements was significantly greater after task-oriented arm training compared to general upper extremity exercises. Action Research Arm Test scores also improved after task-oriented arm training compared to exercises in the control group. The task-oriented arm training improves the gross and fine motor activities and encouraging the use of the paretic arm through activity dependent intervention expedites the recovery of functional activities in the upper extremities for chronic hemiparetic stroke.

• Nuclear Engineering and Technology
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• v.44 no.8
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• pp.889-896
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• 2012

Recent progress in the computational fluid dynamics methods of two- and multiphase phase flows has already started opening up new exciting possibilities for using complete multidimensional models to simulate boiling systems. Combining this new theoretical and computational approach with novel experimental methods should dramatically improve both our understanding of the physics of boiling and the predictive capabilities of models at various scale levels. However, for the multidimensional modeling framework to become an effective predictive tool, it must be complemented with accurate mechanistic closure laws of local boiling mechanisms. Boiling heat transfer has been studied quite extensively before. However, it turns out that the prevailing approach to the analysis of experimental data for both pool boiling and forced-convection boiling has been associated with formulating correlations which normally included several adjustable coefficients rather than based on first principle models of the underlying physical phenomena. One reason for this has been the tendency (driven by practical applications and industrial needs) to formulate single expressions which encompass a broad range of conditions and fluids. This, in turn, makes it difficult to identify various specific factors which can be independently modeled for different situations. The objective of this paper is to present a mechanistic modeling concept for both pool boiling and forced-convection boiling. The proposed approach is based on theoretical first-principle concepts, and uses a minimal number of coefficients which require calibration against experimental data. The proposed models have been validated against experimental data for water and parametrically tested. Model predictions are shown for a broad range of conditions.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4395-4407
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• 2023

Bubble columns are widely encountered in several industries, especially in the field of nuclear safety. The Eulerian-Eulerian and the Eulerian-Lagrangian methods are commonly used to investigate bubble columns. Eulerian approaches require additional tasks such as strict volume conservation at the interface and a predefined well-structured grid. In contrast, the Lagrangian approach can be easily implemented. Hence, we introduce a fully Lagrangian approach for the simulation of bubble columns using the discrete bubble model (DBM) and moving particle semi-implicit (MPS) methods. Additionally, we propose a rigorous method to estimate the volume fraction accurately, and verified it through experimental data and analytical results. The MPS method was compared with the experimental data of Dambreak. The DBM was verified by analyzing the terminal velocity of a single bubble for each bubble size. It agreed with the analytical results for each of the four drag correlations. Additionally, the improved method for calculating the volume fraction showed agreement with the Ergun equation for the pressure drop in a packed bed. The implemented MPS-DBM was used to simulate the bubble column, and the results were compared with the experimental results. We demonstrated that the MPS-DBM was in quantitative agreement with the experimental data.

• Journal of Korean Elementary Science Education
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• v.34 no.2
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• pp.252-263
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• 2015

This study analyzed the effects of science outdoor activity applying a Brain-Based Evolutionary (ABC-DEF) approach on elementary school students' interest and academic achievement. Samples of the study were composed of 3 classes of 67 sixth graders in Seoul, Korea. Unit of 'Ecosystem and Environment' was selected as a object of the research. Textbook- and teachers' guidebook-based instruction was implemented in comparison group, brain-based evolutionary approach within classroom in experimental group A, and science outdoor learning by a brain-based evolutionary approach in experimental group B. In order to analyze the quantitative differences of students' interests and achievements, three tests of 'General Science Attitudes', 'Applied Unit-Related Interests', and 'Applied Unit-Related Achievement' were administered to the students. To find out the characteristics which would not be apparently revealed by quantitative tests, qualitative data such as portfolios, daily records of classroom work, and interview were also analyzed. The major results of the study are as follows. First, for post-test of interest, a statistically significant difference between comparison group and experimental group B was found. Especially, the 'interests about biology learning' factor, when analyzed by each item, was significant in two questions. Results of interviews the students showed that whether the presence or absence of outdoor learning experience influenced most on their interests about the topic. Second, for post-test of achievement, the difference among 3 groups according to high, middle, and low levels of post-interest was not statistically significant, but the groups of higher scores in post-interest tends to have higher scores in post-achievement. It can be inferred that outdoor learning by a brain-based evolutionary approach increases students' situational interests about leaning topic. On the basis of the results, the implications for the research in science education and the teaching and learning in school are discussed.

• Earthquakes and Structures
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• v.14 no.6
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• pp.551-565
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• 2018

Experimental testing is considered the most realistic approach to obtain a detailed representation of the nonlinear behaviour of masonry-infilled reinforced concrete (RC) structures. Among other applications, these tests can be used to calibrate the properties of numerical models such as simplified macro-models (e.g., strut-type models) representing the masonry infill behaviour. Since the significant cost of experimental tests limits their widespread use, alternative approaches need to be established to obtain adequate data to validate the referred simplified models. The proposed paper introduces a detailed finite element modelling strategy that can be used as an alternative to experimental tests to represent the behaviour of masonry-infilled RC frames under earthquake loading. Several examples of RC infilled frames with different infill configurations and properties subjected to cyclic loading are analysed using the proposed modelling approach. The comparison between numerical and experimental results shows that the numerical models capture the overall nonlinear behaviour of the physical specimens with adequate accuracy, predicting their monotonic stiffness, strength and several failure mechanisms.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.1084-1087
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• 2000

This paper presents a new approach to evaluate the maximum number of simultaneous switching gates of a given combinational circuit. The new approach is based on an iterative method proposed by Sinogi et al. and applies a simulated annealing strategy to search jot a new solution. The experimental evaluation using ISCAS’85 benchmark circuits shows that the proposed approach has attained an excellent improvement compared with other rotated methods including the iterative method.

• Physical Therapy Korea
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• v.18 no.2
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• pp.18-26
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• 2011

The purpose of this study was to investigate the effects of a task-oriented approach on weight-bearing distribution and muscular activities of the paretic leg during sit-to-stand movement in 18 chronic stroke patients. Both groups were received neurodevelopmental treatment for 30 min/day and then the experimental group ($n_1$=9) followed additional a task-oriented approach (sit-to stand training with controlled environment) and the control group ($n_2$=9) followed a passive range of motion exercise for 15 min/day, five days/week, for four weeks. Weight-bearing distribution and muscular activities of the paretic leg during sit-to-stand movement were measured before and after four weeks of training. There was significantly improved weight-bearing distribution of the paretic leg during sit-to-stand movement in the experimental group compared with that of the control group after four weeks of training (p<.05). But electromyographic activities of the quadriceps and the tibialis anterior of the paretic leg were not significantly different (p>.05). Thus, it is necessary to apply a task-oriented approach to improve the weight-bearing distribution of the paretic leg during sit-to-stand movement in chronic stroke patients.

• Journal of the Korea Concrete Institute
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• v.12 no.1
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• pp.3-12
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• 2000

A fracture energy concept proposed by Ouyang and Shah's fracture mechanics approach was used to predict cracking of reinforced concrete members subjected to tension. In this approach, fracture properties in plain concrete which incorporate the presence of the fracture process zone are first determined from the generalized size effect method, then fracture energy required for crack propagation with the same dimension and material properties are evaluated using an R-curve. Subsequently taking into account the material properties in Ouyang and Shah's approach, a theoretical analysis to predict the mechanical behavior of reinforced concrete members subjected to tension was performed and compared to observed experimental results. It is seen that the predicted average crack spacing curves agree well with the experimental results, whereas the analytical method seems to predict lower values for this study. The analytical approach predicts well responses of stress-strain curves before and after the first crack is formed. It is concluded from this study that a fracture energy concept based on the R-curve and the generalized size effect method is a rational approach to predict cracking of reinforced concrete members subjected to tension.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.7
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• pp.977-985
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• 2004

An evaluation of fatigue life of welded components is complicated due to various geometrically complex welding details and stress raisers in vicinity of weld beads, ego under cuts, overlaps and blow holes. These factors have a considerable influence on the fatigue strength of welded joints, as well as the welding residual stress which is relaxed depending on the distribution of local stress at the front of the stress raisers. To reasonably evaluate fatigue life, the effect of geometries and welding residual stress should be taken into account. The several methods based on the notch strain approach have been proposed in order to accomplish this. These methods, however, result in differences between analytical and experimental results due to discrepancies in estimated amount of relaxed welding residual stress present. In this paper, an approach that involves the use of a modified notch strain approach considering geometrical effects and a residual stress relaxation model based on experimental results was proposed. The fatigue life for five types of representative welding details, ego cruciform, cover plate, longitudinal stiffener, gusset and side attachment joint, are evaluated using this method.

• Korean Journal of Child Studies
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• v.33 no.1
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• pp.165-181
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• 2012

The purpose of this study was to verify the effects of the Orff Approach to music education programs on singing ability, the ability to play musical instruments, physical expression ability, musical improvisation ability as well as overall musical expressiveness in 5 year old children. The test subjects for this study consisted of fifty-eight children. They were arbitrarily assigned to the experimental group of 31 children and the control group of 27 children. The experimental group was engaged using the Orff music education program for a total of 16 sessions, while the control group conducted music activities according to the annual music education plan of M kindergarten. The main results of this study were as follows : The Orff Approach to music education program was effective in improving abilities in the sub-factors of the four kinds of musical expression ability (singing, playing musical instruments, physical expression and musical improvisation) as well as overall musical expressive abilities. These results indicate that the Orff Approach to music education programs can create positive effects in the developing musical expressiveness of young children.