• 한국산학기술학회논문지
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• 제7권5호
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• pp.852-857
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• 2006

본 논문은 디지털 지도를 이용하여 산악지형의 전계강도를 정밀하게 분석하는 방법을 제시한다. 일반적으로 전파의 전계 강도는 직접파와 수평면 반사를 주로 고려하였으나, 산악지역에서는 직접파와 수평면 반사 외에도 산악지형의 수직면에 의한 반사도 고려해야 한다. 이러한 점을 고려하여 산악지형에서 전파를 송신할 때 일어나는 직접파와 수평면 반사파, 산악 지형에 의한 수직면 반사파의 합성 전계를 전파의 편파 특성과 위상 특성을 고려하여 계산한 결과를 제시하였다.

• Nuclear Engineering and Technology
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• 제52권4호
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• pp.856-862
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• 2020

Defect inspection system for industrial applications takes the important portion. Non-destructive inspection method has been significantly improved. Infrared thermography, as one of method for non-destructive inspection, can provide relatively precise data and quick inspection time. This study, it was performed to measure defect according to the measurement limit of the non-visible areas such as the back surface of the pipe using reflection plate using reflection plate based on Infrared thermography. The materials of the reflection plate were determined in consideration of the space limitation and the thermal characteristics, and defects were detected by the manufactured reflection plate. Detection of defect in non-visible area using the candidate materials for reflection plate was conducted.

• 동력기계공학회지
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• 제15권3호
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• pp.18-24
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• 2011

In this study, the reflection of the L(0,2), axially symmetric guided elastic wave from defects in pipes above ground is examined using finite element method. Phase and group velocity dispersion curves for the pipe were presented for the selection of the excitation mode. Some simple signal processing was applied to determine the amplitude of each of the reflected waves and to calculate the reflection coefficient. The results show the reflection coefficient of this mode is very close to a linear function of the circumferential extent of the defect. The motivation for the work was the development of a technique for inspecting chemical plant pipelines, but the study addresses the nature of the reflection function and its general applicability.

• 한국안광학회지
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• 제3권1호
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• pp.201-207
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• 1998

눈의 cornea, crystalline의 reflection pattern을 알기 위해 matrix를 이용하여 image의 위치, size를 이론적으로 계산하였고, 3개의 light source와 reflex camera를 이용하여 reflection pattern를 측정할 수 있는 system을 만들었다. 단일 광원을 이용하여 retina에서 반사 pattern으로부터 눈의 원시 및 근시 등을 측정하였고, 2개의 광원을 이용한 reflection pattern으로부터 cornea, crystalline의 curvature를 측정하였다.

• International Journal of Human Ecology
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• 제9권1호
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• pp.71-79
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• 2008

Service-Learning pedagogy includes community service and reflection as main components. Students can learn integration and application of knowledge beyond specific fields through experiences and reflection. The purpose of family and Consumer Sciences Education is related to connect theory and practice to improve individual, family, and community life. The curriculum focuses not only on content mastery in subjects, but also application of that knowledge to the real lives of students. Considering the purpose of service-learning as integration and application of knowledge, service- learning pedagogy can contribute to rethink family and Consumer Sciences Education. Reflection as a key component is examined for service-learning pedagogy. Exploring a deeper meaning of reflection in aspects of community connection, critical thinking, and transformative learning would extend the value of it and provide implications for implementing reflection in service-learning pedagogy in Family and Consumer Sciences Education.

• 반도체디스플레이기술학회지
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• 제20권1호
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• pp.108-112
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• 2021

Undesired reflection removal from an image captured through glass window is widely needed with the prevalence of camera. In this paper, we present and implement a reflection removal algorithm, which is specially designed for smart devices. Our implementation requires smart phone application to take two input pictures of the same target, one with flash light on and another with flash light off. Then, we find a flash spot in the picture, match the features to align the input pictures, transform the color space, and finally combine the pictures. As the result, we get a resulting image with removed reflection, achieving the visually pleasant.

• 한국안광학회지
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• 제1권1호
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• pp.93-102
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• 1996

렌즈의 광학계의 분광투과률을 높이기 위한 방법으로 무반사막의 다층화에 의한 광대역화와 낮은 반사률이 중요하다. 그러나 잔류반사광이 발생하여 반사색광이 미약하게 나타난다. 이런 반사색광은 두께, 굴절율, 층수, 입사광의 파장, 기판물질 등의 구조에 의한 반사광의 파장 영역을 제어할 수 있다. l층, 2층 구조에서 ${\lambda}s/{\lambda}$=1.0인 조건하에서 무반사시키면, 다른 영역에서 나온 반사광들이 색혼합된 반사색광을 얻을 수 있고, 3층 구조에서 ${\lambda}0/{\lambda}$가 $PI{\ll}1$, $P2{\gg}1$ 에서 무반사시키면 P1< ${\lambda}0/{\lambda}$

• 한국지역사회생활과학회지
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• 제24권3호
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• pp.301-312
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• 2013

The purpose of this study was to investigate the differences between attentional networks according to sex and reflection-impulsivity in the cognitive styles of young children. The subjects of the study were 78 5-year-old children from the kindergarten or daycare center in Busan(with 40 in the reflection group, and 38 in the impulsivity group). The tests were conducted by using the Mating Familiar Test and the Attentional Network Test for young children. The study has used two independent t-tests to find out the differences between attentional networks according to sex, and reflection-impulsivity in the cognitive styles of young children. The results of this study were as follows. First, the boys with reflection cognitive style were significantly slower than the girls with the same style(t=2.18, p<.05). Second, young children with reflection cognitive style were significantly faster in the case of alerting effects than those with impulsivity cognitive style(t=-2.53, p<.05). The young children with reflection cognitive style were slower than those with impulsivity cognitive style in the case of orienting effect(t=2.04, p<.05). Children with a combination of both conflict effect and reflection cognitive style were significantly faster than those with impulsivity cognitive style(t=-2.89, p<.01). The results of the study suggested that there was a difference between attentional networks according to sex and reflection-impulsivity cognitive styles of young children.

• 대한기계학회논문집B
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• 제23권11호
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• pp.1473-1480
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• 1999

In the case of Impingement of plane moving shock wave over concave or convex double wedges (pseudo-stationary flow) and cylindrical walls (truly non-stationary flow), it Is expected that there are transitions from regular reflection to Mach reflection or vice versa In shock wave reflections. In these connections, it is necessary to verify the various of reflection process and transition angle for the reflection problems In double wedges, and to verify the transition angle, effects of curvature radius and initial wall angle on it for the reflection problems In cylindrical walls. Especially, we focused our attention to confirm the existence of hysteresis phenomenon induced by the different transition processes, and Neumann paradox, which is a small discrepancy between theoretical and experimental transition angles. Experiments were carried out by using the shock tube of $6{\times}6cm^2$, and high speed photographic technique consisted of delay unit, triggering system, light source of Xe lamp and so on was used for flow visualization.

• ETRI Journal
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• 제21권3호
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• pp.41-48
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• 1999

We have calculated differential reflection coefficient for isolated well structure of micro-scale, etched on dielectric surface. The differential reflection coefficient is computed using Green's second integral theorem. The purpose of our computation is to find a class of well profiles which give maximal diffusive scattering. To have such a maximal effect, we have concluded that the waist radius of Gaussian beam and its wavelength should be comparable to the well width and that well depth has to be larger than a wavelength. Exact calculation of differential reflection coefficients of dielectric surface with isolated structure on it may be used for the examination of dielectric surfaces and also in making simple but efficient diffuser.