• Journal of the Korean School Mathematics Society
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• v.14 no.2
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• pp.123-142
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• 2011

Recently, a number of researches acknowledge the importance of 'reflection' and 'reflective teacher education,' and they highlight the implication of 'reflection' on the teacher's profession or the teacher education. The reflective thought is interpreted as a subject that should be taught or a sort of strategy that a teacher should learn, while the aspect is excluded that reflection is the interaction between the innate knowledge and the practice. As a result, the reflective teacher education programs that increase the level of reflection are developed and practiced, and the reflection is accepted as a tool for increasing teacher professionalism. Reflective teaching is en essential and basic element for the development of teacher knowledge. In particular, such teacher knowledge might be being gradually expanded by a teacher's self-assessment on reflection on his own instruction. For this reason, this study develops an assessment framework on instruction which is comprized of teacher knowledge and instructional process. To accomplish this, in this study, teacher knowledge is considered as a whole practice knowledge combined by subject matter knowledge, understanding of learners, teaching and learning methods and assessment, and instructional environment. Also, success on instruction in mathematics class might depend on the acquisition of teacher knowledge, instructional planning, instructional execution, and furthermore reflection on instruction. Especially, this study emphasizes that 'reflection on instruction', the most important step of instruction be reflected and examined by the teacher himself.

• International Journal of Highway Engineering
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• v.18 no.1
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• pp.57-62
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• 2016

PURPOSES : Reflection cracking has been one of the major causes of distress when asphalt pavement is laid on top of concrete pavement. This study evaluated the reflection cracking resistance of asphalt mixtures reinforced with asphalt embedded glass fiber and carbon fiber using a Texas Transportation Institute (TTI) overlay tester. METHODS : Different asphalt mixtures such as polymer-modified mastic asphalt (PSMA) and a dense graded asphalt mixture were reinforced with asphalt-embedded carbon fiber and glass fiber. For comparison purposes, two PSMA asphalt mixtures and one dense graded asphalt mixture were evaluated without fiber reinforcement. Two different overlay test modes, the repeated overlay test (R-OT) and monotonic overlay test (M-OT), were used to evaluate the reflection cracking resistance of asphalt mixtures at $0^{\circ}C$. In the R-OT test, the number of repeated load when the specimen failed was obtained. In the M-OT test, the tensile strength at the peak load and tensile strain were obtained. RESULTS : As expected, the fiber-reinforced asphalt mixture showed a higher reflection cracking resistance than the conventional nonreinforced asphalt mixtures based on the R-OT test and M-OT test. The dense graded asphalt mixture showed the least reflection cracking resistance and less resistance than the PSMA. CONCLUSIONS : The TTI overlay tester could be used to differentiate the reflection cracking resistance values of asphalt mixtures. Based on the R-OT and M-OT results, the carbon-fiber-reinforced asphalt mixture showed the highest reflection cracking resistance among the nonreinforced asphalt mixtures and glass-fiber-reinforced asphalt mixture.

• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1397-1404
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• 2009

It is the aim of this paper to consider the reflection symmetries of the Genocchi polynomials $G^*_n(x)$. We display the shape of Genocchi polynomials $G^*_n(x)$. Finally, we investigate the roots of the Genocchi poly-nomials $G^*_n(x)$.

• The Journal of Korean Association of Computer Education
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• v.22 no.5
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• pp.27-37
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• 2019

In this study, for the purpose of reflection level analysis of high school students in HW design learning which is based on online simulation, we carried out 5 lessons of HW learning and analyzed there reflection levels for 5 individual time of reflection content. The reflection level analysis results for each time of learning shows that the reflection level of the $3^{rd}$ time learning of D-Flip Flop is the highest score with 1.23. The correlation analysis result between the reflection contents presents that high positive correlation between learning content and task resolving method(r=.781, p<.01), and negative design correlation between task resolving method and alternative resolving method. The HW learning satisfaction survey result shows 4.2, and most of the participant students provided opinions that the HW design learning is required and current learning contents is a bit difficult to follow. We could recognize HW design learning is required to have composition of curriculum with basic and advanced contents, and on-off lines combined.

• Bulletin of the Korean Mathematical Society
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• v.35 no.2
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• pp.269-278
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• 1998

Let ($G,\;{\upsilon}$) be a bounded smooth domain and reflection vector field on $\partial$G, which points uniformly into G. Under the condition that locally for some coordinate system, ${\mid}{\upsilon^i}{\mid}\;i\;=\;1,{\cdot},{\cdot}$,d - 1, where is constant depending on the Lipschitz constant of G, we have tightness for reflected diffusion with jump on G with reflection $\upsilon$ depending only on c. From this, we obtain some properties of L-harmonic function where L is a sum of Laplacian and integro one.

• Journal of Christian Education in Korea
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• v.75
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• pp.59-81
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• 2023

Purpose of study: The purpose of this study is to analyze the experience of writing a learning reflection journal, identify the effects, and propose an effective learning reflection journal activity way. Research content and method: This study examined the theoretical background of the concept and educational effect of the learning reflection journal through literature review in terms of educational and Christian educational aspects, and analyzed the learning reflection journal experience through the interviews with six students. Through this, this study identifies the effectiveness of the learning reflection journal and suggests effective learning reflection journal activity way that can be applied to training that can grow as a Christian educator who practices what he or she know through major classes. Conclusions and Suggestions: For effective learning reflection journal activities, it was proposed to reduce the number of review and reflection questions so that they would not be burdensome, to include questions in a balanced way, to help learners to improve class attitudes. It was also proposed that the submission period and the number of writing journals should be agreed upon with the students at the beginning of the semester.

• Communications of Mathematical Education
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• v.33 no.1
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• pp.35-45
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• 2019

Reflection and Meta-Cognition became the centered interest as main subjects of the mathematics education studies together with problem solving education in the 1980s. And lots of researches who have concerned with them have been even progressed actively. But, the concept of the reflection and particularly meta-cognition has been pointed out continually because of its ambiguity and uncertainty. There is almost no researches intended to reveal the concept itself. Although the status of the reflection and/or meta-cognition in mathematics education. Therefore, it is significant at this point in time that the work of examining the concept of the reflection and meta-cognition be accomplished. By this reason, this study tried to examine and find out the essential nature of the concept of reflection and meta-cognition in aspects of mathematics education.

• Journal of Ocean Engineering and Technology
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• v.1 no.1
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• pp.138-143
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• 1987

Friction welding has emerged as a reliable process for high-production commercial applications with significant economic and technical advantages. But nondestructive test in friction weld was not clearly developed. Therefore the experimental verification is necessary in order to understand the characteristcs of the pulse echo effects according to various change in welding conditions. This paper presents an attempt to determine the relationship between the varios welding conditions and the coefficients of reflection using the ultrasonic pulse echo method in dissibilar metals friction weld. The new approach of calculating the coefficients of reflection based on measured amplitudes of the echoes is applied in this paper. These coefficients provides a single quantitative measurement which involves both acoustic energy reflected at the welded interface as well as transmitted across the interface. As a result, it was known that the quantitave relationship between welding conditions and the coefficients of reflection using the ultrasonic pulse echo exists in dissimilar metals friction weld.

• Journal of Integrative Natural Science
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• v.3 no.3
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• pp.138-142
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• 2010

Polystyrene thin films containing Bragg structures have been successfully obtained by the removal of DBR porous silicon films from the DBR structured porous silicon/polystyrene composite film in HF/$H_2O$ mixture solution and by replicating the nano-structures of porous silicon containing Bragg structure. Polystyrene thin films containing Bragg structures displayed unique optical reflection resonances in optical reflection spectrum. This optical reflection band was resulted from the interference of reflection wavelength at Bragg structure of polystyrene thin films. The wavelength of reflection resonances could be modified by the change of Bragg structure of the master. Polystyrene thin films containing Bragg structures were flexible and maintained their optical characteristics upon bending. The Polystyrene thin films replicate the photonic features and the nanostructure of the master.

• The Journal of the Acoustical Society of Korea
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• v.25 no.1E
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• pp.1-7
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• 2006

This study examines the reflection characteristic of a thin transition layer of the ocean bottom showing variability with respect to depth. In order to model the surficial sediment simply, we reduce the Biot model to the depth dependent wave equation for the pseudo fluid using the fluid approximation (weak frame approximation). From the reduced equation, the difference between the inherent frequency dependency of the reflection and the frequency dependency resulting from a thin transition layer is investigated. Using Tang's depth porosity profile model of the surficial sediment [D. Tang et al., IEEE J. Oceanic Eng., vol.27(3), 546-560(2002)], we numerically simulated the reflection loss and investigated the contribution from both frequency dependencies. In addition, the effects of different sediment type and varying depth structure of the sediment are discussed.