• Journal of the Korean Institute of Telematics and Electronics
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• v.6 no.3
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• pp.8-11
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• 1969

In the precision measurement of the voltage standing wave ratio (VSWR) or reflection coefficient by means of the slotted line technique, one of the important factors is the maximum error due to the discontinuities and multi-reflection in the slotted line. Particularly, this error becomes a critical factor when the VSWR or the reflection coefficient to be measured is very small. In this paper, the exact expression of this error is obtained by means of the Signal flow graph method.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.6
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• pp.55-62
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• 2008

An Estimation of VHF datalink range for EW(Electronic Warfare) equipment in the sea environment was studied to predict the datalink range between transmitting and receiving station. We consider refraction and reflection in addition to the basic radar equation. The reflection especially includes propagation factor in case of spherical earth as well as flat earth. The estimation result can predict the real datalink range within 5% error.

• Current Photovoltaic Research
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• v.8 no.1
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• pp.1-5
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• 2020

The most important factor in enhancing the performance of an optical device is to minimize reflection and increasing transmittance of light for a broad wavelength range. The choice of appropriate coating material is crucial in decreasing reflection losses at the substrate. The purpose of this review is to highlight anti-reflection coating (ARC) materials that can be applied to silicon solar cell and glass substrate for minimizing reflection losses. The optical and electrical behavior of ARC on a substrate is highly dependent on thickness and refractive index (RI) of ARC films that are being deposited on it. The coating techniques and performance of single and multi-layered ARC films after coated on a substrate in a wide range of wavelength spectrum will be studied in the paper.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.170-173
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• 2005

The objective of this paper is to perform measurements of power transmission and reflection coefficients in a coupled plate. The coupled plate has been divided into 2 subsystems. The out-of-plane vibration has been only considered with assumption of relatively small in-plane vibration. The coupling loss factors have been measured with consideration of the power balance condition. The power transmission and reflection coefficients has been estimated from the measured values of the coupling loss factors. The measured power transmission and reflection coefficients have been compared with the corresponding theoretical coefficients in a semi-infinite coupled plate.

• Progress in Superconductivity and Cryogenics
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• v.19 no.2
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• pp.29-32
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• 2017

The use of electronic devices such as mobile phones and tablet PCs has increased of late. However, the power which is supplied through wires has a limitation of the free use of devices and portability. Magnetic-resonance wireless power transfer (WPT) can achieve increased transfer distance and efficiency compared to the existing electromagnetic inductive coupling. A superconducting coil can be applied to increase the efficiency and distance of magnetic-resonance WPT. As superconducting coils have lower resistance than copper coils, they can increase the quality factor (Q-factor) and can overcome the limitations of magnetic-resonance WPT. In this study, copper coils were made from ordinary copper under the same condition as the superconducting coils for a comparison experiment. Superconducting coils use liquid nitrogen to keep the critical temperature. As there is a difference of medium between liquid nitrogen and air, liquid nitrogen was also used in the normal conductor coil to compare the experiment with under the same condition. It was confirmed that superconducting coils have a lower reflection-coefficient($S_{11}$) than the normal conductor coils.

• The Journal of the Korea Contents Association
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• v.13 no.7
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• pp.9-15
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• 2013

In the VnR (Virtual and Real Worlds) of recent virtual reality convergence, the modelling of realistic human face is focused on the facial appearance such as the shape of facial parts and muscle movement. However, the facial changing parameters caused by environmental factors beyond the facial appearance factors can be regarded as important ones in terms of effectively representing virtual avatar. Therefore, this study evaluates user's visual feeling response according to the opacity variation of eye reflection of virtual avatar which is considered as a new parameter for reprenting realistic avatar. Experimental result showed that more clear eye reflection induced more realistic visual feeling of subjects. This result can be regarded as a basis for designing realistic virtual avatar by supporting a new visual realistic representing factor (eye reflection) and its degree of representation (reflectance ratio).

• Journal of the Korean Home Economics Association
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• v.39 no.2
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• pp.97-110
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• 2001

The purpose of this study was to analyze a causal relations of children's self-control, self-concept, reflection, age, sex and mother's parenting. The subjects were 86 children of 5-and 6-year=olds, and their mothers and leachers. The instruments were TSCRS, MFFT, Self-concept inventory and Parenting scale. The major findings of this study were as follows; (1) Children's reflection, social self-concept and mother's control parenting predicted children's self-control. 20% of the valiance of children's self-control was explained by these variables. (2) Children's reflection was the first contribution factor and had a direct positive effect on children's self-control. Children's social self-concept had a direct positive effect on children's self-control. Mother's control parenting had a direct negative effect on children's self-control. (3) Mother's affect parenting had an indirect positive effect through children's reflection and social self-concept on children's self-control. Children's sex had indirect effect through mother's control and affect parenting on children's self control. Children's age had indirect effect through children's reflection and mother's control parenting on children's self-control.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.228-233
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• 2008

The reflection type photoelastic experiment can be used more effectively than the transparent type photoelastic experiment in industrial fields. However, the reflection type photoelastic experiment for orthotropic material has not been studied. Therefore, the reflection type photoelastic experimental hybrid method for the fracture mechanics of orthotropic material was developed in this research. Comparing the results obtained from this method with those from the hybrid method for isotropic material about the same isotropic specimen, the validity of this method was verified. And then, the reflection type photoelastic experiment for orthotropic material was applied to the orthotropic plates with a central crack of the various inclined angle. Using this hybrid method for the orthotropic material, it is able to obtain stress intensity factors and separate stress components at the vicinity of the crack-tip in orthotropic plates from only the isochromatic fringe patterns of isotropic coating material.

• The Korean Nurse
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• v.31 no.5
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• pp.65-71
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• 1992

In nursing, a practice discipline, it has been argued whether the mastery of clinical competence depends on types of learning styles, learning experience, and the use of specialized skills. All these problems are not limited to nursing education. Later educators identified the importance of reflective learning which is a vital element in any form of learning and that teachers and students need to consider how they can incorporate some forms of reflection in the courses. The purpose of this study is to review educational articles for understanding better what reflection in learning is, to identify the theme which is of important relevance to professional practice, from the book, Educating the reflective practitioner, and to discuss the theme within nursing education. Reflection in learning was defined by Dewey(1933) as the process which is involved the perception of relationships and connections between the parts of an experience. This experience is passed on when two people becoming involved with each other in a conversation. schon(1987) emphasized that learning conversation, which is a part of the interaction of student and teacher, is an important factor of the process of reflection-om-actopm. In clinical nursing education, good relationships between teacher and student, faculty's role, interpersonal skills are critical in learning conversation. Then Practing nurses who accept the need to choose nursing actionss on the basis of reflection, who accepet the necessity for understanding and being able to communicate the reasons for action are a powerfful force for the development of nursing into an increasingly more effective profession for the benefit of patients.

• Applied Chemistry for Engineering
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• v.28 no.1
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• pp.35-41
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• 2017

Materials exposed to outside will deteriorate due to various weathering factors such as sunlight, heat, temperature, humidity and so on. Therefore, predicting speed of degradation and life time is a very important issue. This research uses retro-reflective sheets with white and green which are most commonly used colors to conduct the outdoor exposure test and acceleration test of xenon arc in Arizona state in the United States, Chennai in India, Sanary in France and Seosan in Korea to measure the reflective performance of retro-reflection. The accelerated factor was obtained by using regression analysis through reflective values obtained from the acceleration test of xenon arc from Seosan area. Also, by using solar uv program, the accelerated factor of various climate regions were obtained and it was confirmed that the accelerated factor of Senary was 1.04, Arizona 1.82, Chennai 1.92 times higher than that of Seosan.