• 한국수산과학회지
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• 제20권4호
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• pp.370-378
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• 1987

Wave reflection control functions of mound for the foundation of composite and perforated break-waters were investigated through the theoretical considerations. The theory developed is based on a simple summation of components of reflected waves. The applicability of the theory is assured by the comparative studies of the theoretical calculation and experimental data on the sea surface elevation in front of a breakwater. It is found that the reflection is mainly controlled by depth and width of the mound. In the design of composite type perforated breakwaters, the width of perforated part of the upright section can be decreased to less than half of the conventional design width for the same reflection by using the reflection control function of mound part and the reflection can be reduced until less than $30\%$ of that in the composite breakwaters. Using the results, a design method of mounds is proposed, by which the reduction of wave reflection is assured under the given wave conditions.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.395-395
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• 2011

일반적으로 태양전지에서 anti-reflection layer는 조사되는 태양 광을 좀 더 많이 사용하기 위하여 nitride나 oxide와 같은 막을 표면에 형성한다. 본 연구는 이 anti-reflection으로 사용되는 nitride와 oxide의 각각의 두께와 굴절률 변화에 따른 특성변화를 SILVACO를 이용하여 전산모사하고 그 특성변화를 분석하였다. Anti-reflection layer가 없을 경우에는 조사된 빛에 따른 available photo current 활용이 낮았으며, 특히 그 경향은 단파장영역에서 두드러지게 나타났다. 따라서 anti-reflection layer의 최적화를 위해서 두께를 가변하여 available photo current를 분석하였으며, 각 물질의 굴절률 변화 및 이중층 구조의 anti-reflection layer를 형성하고 특성변화를 분석함으로써 최적화하였다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.213-216
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• 2008

In this study, reflection coefficients of regular and random waves propagating over multi-arrayed trenchs are calculated respectively. When the row of trench is 3, the reflection coefficient of regular waves is more than 0.7 as maximum value. Similarly, when the row of trench is 3 and $d/L_1$ is 0.22, reflection coefficient of multi-directional random waves is more than 0.4 maximally.

• 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.

• 한국주거학회논문집
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• 제24권6호
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• pp.33-40
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• 2013

Hiroshi Hara is one of the most famous architect in the history of contemporary Japanese architecture. During the 1970's beginning with the Awazu Residence (1972), he designed a series of symmetrical houses, the so called 'Reflection House'. All the houses in this period were based on the method of 'reflection' and 'inversion', which means a radical reversal of the accepted notion that houses are parts of cities. A concept of "A house within a house" is expanded to "A city within a house". The important spatial characteristics of 'Reflection House' are main internal core and valley-like spaces forming internal urban streets by bringing natural elements and the components of streetscape such as plaza, open space, context of street facades and so on. This procedure is called as embedding 'city' into 'house', Hara mentioned. This paper investigates the outline of the 'Reflection House' and analyses the completed works of housing that were based on the theory. Then in the final part of the paper, the implications of 'Reflection House' and its influence on his later works of following period will be discussed.

• 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.

• 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.

• 한국과학교육학회지
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• 제35권3호
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• pp.523-536
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• 2015

본 연구에서는 대학교와 학교 현장의 연계를 통하여 진행된 실험교실의 사례에서, 3년간의 수업 후 평가회에서 나타나는 예비교사 공동체의 반성을 문화역사활동이론의 관점에서 분석하였다. 먼저, $Engestr{\ddot{o}}m$이 제안한 활동 체계를 이용하여 사회문화적 요소를 파악하였고, 반성의 양상을 '반성 주제의 다양성'과 '반성의 실제성'의 측면으로 구분하여 살펴보았다. 그리고 공동체의 반성과 실행의 순환 과정 속에서 나타나는 한계점을 살펴보았다. 분석 결과, 3년간의 수업 후 평가회에서 예비교사 공동체 반성의 사회문화적 요소는 변화하였는데, 수업평가회의 정례화, 도구의 도입, 평가회 운영 주체의 변화가 두드러지게 나타났다. 이 과정 속에서 반성의 주제는 다양해지고, 실제적인 논의가 이루어졌다. 그러나 시간 관리, 학생의 참여, 지도서인 '멘토의 역할'에 대해서는 반성적 실천이 발전되지 못하고 매번 비슷한 패턴의 논의가 반복되었다. 이러한 결과 분석을 토대로 활동체계의 측면에서 예비교사 공동체의 반성적 논의를 촉진시킬 수 있는 방법에 대하여 제언하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1078-1082
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• 2005

In this study, the run-up height and reflection property on slopes of S-berm and smooth slopes breakwaters are investigated by laboratory experiment. The run-up height analyzed the effect of reflection coefficient, surf similarity parameter. Measured reflection coefficients of smooth slope breakwaters are compared with those of S-berm breakwater with variable widths. In general, measured coefficients of S-berm breakwaters are smaller than those of smooth slope breakwaters.