• 대한치과교정학회지
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• 제23권4호
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• pp.619-631
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• 1993

Tooth movement by segment is one of the means which are frequently used in daily orthodontic practice. When we retract or intrude a tooth or teeth, we should recognize the center of resistance of the certain tooth or teeth. There have been many studies about the center of resistance of a single tooth, not so much was about the tooth-segment. At the present study the center of resistance of the maxillary anterior segment is experimentally investigated by using laser reflection technique and metal splints on the human dry skull. The variables of intrusive force magnitude are divided into two groups, 50g and 100g groups. The results were as follows ; 1. The center of resistance of the maxillary anterior segment composed of the central and lateral incisors was at the mesial portion of canine crown at the coronal level. 2. The center of resistance of the maxillary anterior segment composed of the central and lateral incisors and canines is between the canine and the 1st premolar crowns at the coronal level.

• 한국지역지리학회지
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• 제17권4호
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• pp.459-476
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• 2011

본 연구는 반성방법의 차이에 따른 예비 지리교사의 수업전문지식 변화를 파악하는 데 목적을 두고 있다. 연구 목적을 달성하기 위해 l차 모의수업 결과를 토대로 통일한 수준에 있는 데 명의 예비교사들을 선정한 후, 각각 상이한 반성을 거쳐 2차 모의수업을 실시하도록 하였다. 이 때 각각의 수업에 대한 동료평가를 실시함으로써 예비교사들의 수업전문지식 구비정도를 파악했고, 1차 및 2차 수업 간의 점수를 비교함으로써 반성방법의 차이에 따른 수업전문지식의 변화 양상을 파악했다. 연구 결과는 다음과 같다. 먼저, 1차와 2차 모의수업을 비교해본 결과 모든 예비교사의 평균점수가 상승했지만, 반성하지 않거나 자기반성을 행한 예비교사에 비해 전문가와의 협력적 반성을 행한 예비교사의 점수가 큰 폭으로 향상되었다. 다음으로 자기반성을 통해 반성적 성찰지를 작성한 예비교사의 경우 반성적 사고는 가능했지만 반성적 실천으로 이어지는 데에는 한계가 나타났다. 마지막으로 통계적으로 유의미한내용지식의 향상은 전문가와의 협력적 반성을 행한 예비교사에게만 나타났다. 특히 영역과 학습자에 대한 이해 영역에서 유의미한 통계 값이 나타났다. 이를 통해 내용이나 상황영역 부문은 예비교사 스스로의 자기반성 및 반복적 수업 실연을 통해서도 향상될 수 있지만, 영역과 학습자에 대한 이해 영역은 조력자의 도움이 필요하다는 사실을 도출할 수 있었다.

• 동서간호학연구지
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• 제22권2호
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• pp.113-120
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• 2016

Purpose: The purpose of this study was to explore the levels of self-reflection, self-esteem, and empathy and identify influential factors on happiness index in nursing students. Methods: The data was collected using questionnaires from a convenience sample of 275 nursing students. The data was analyzed with descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and multiple regression. Results: Mean scores of self-esteem, empathy and happiness index were 3.55, 2.89, 3.43, and 66.76, respectively. Self-understanding, self-esteem, and economic status had significant positive effects with a 42% of explained variance of the happiness index. Conclusion: The results suggest that self-understanding, self-esteem, and economic status should be considered as factors when developing intervention strategies to increase the level of the happiness index among nursing students.

• 한국소음진동공학회논문집
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• 제13권3호
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• pp.217-224
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• 2003

In this study, the adaptive triangular beam method(ATBM) considering different sound reflection coefficients and angles of a triangular beam on two or more planes as well as diffraction effect is suggested. The ATBM, subdividing a tracing triangular beam into multiple triangular beams on reflection planes, gives reliable and convergent sound-field analysis results without the dependancy on the number of initial triangular beam segmentation to search sound propagation paths from source to receiver. The validity of the method is verified by the comparison of numerical and experimental results for energy decay curve and steady-state sound pressure level of rooms having direct, reflective and diffractive sound paths.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.255-259
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• 1997

The essence of meridian collateral and acupoints is an overall physiologic unction with the level of multiple unctional states. However it is a pity that until present, so in this paper described about some experimental results of physical reactions of meridian and acupoints. In order to verify meridian pathway and channel theory of energy in body. It is suppose that substance of meridian is pathway channel of the meridian materials. In basic examination, It was analyzed spectrum of reflection waves after beat or continuos vibrate to meridian point and non-meridian point meridian line and non-meridian line. The characteristics of reflection waves similar to flow channel in hydrodynamic. So it be able to suggest that the meridian is pathway and channel in body.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.183-188
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• 2003

This study is to make the fundamentals of sound quality evaluation in regard of acoustical characteristics of passenger compartment. The deviation of frequency response function level within audible frequency is evaluated at receiving point in the research of room acoustics. In this study, frequency response function is the one between speaker and driver's ear positions. The positions of driver and audio speakers are optimized by analysis of acoustic mode of acoustic cavity. The main reflection planes are determined by analysis sound ray path diffused at optimized speaker positions. Finally, designer selects acoustical material by analysis of absorption effect of acoustical materials on the main reflection planes in order to avoid to distortion and fluctuation of frequency response function..

• 한국군사과학기술학회지
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• 제13권3호
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• pp.413-420
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• 2010

An Estimation of VHF data link range for EW(Electronic Warfare) equipment in the sea environment was studied to predict the data link range between transmitting and receiving station. The theoretical estimation predicts within 3% error with actual measurement of VHF data link range at sea. Data link range factors including refraction and reflection are added in the basic wave propagation equation. The effect of refraction and reflection to the range is analysed with quantity level.

• 한국전자통신학회논문지
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• 제3권1호
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• pp.12-18
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• 2008

본 연구에서는 우리는 레이저 변위 측정에서 보다 정밀한 측정(high precision)을 하기 위한 방법을 제시하였다. 제시한 기법은 측정하고자 하는 물체에서 반사되어 나오는 레이저 반사 신호 레벨의 변동에 의한 오차 원인을 찾아 이를 보상하는 방법이며 이를 레이저 변위 측정기에 적용하여 설계하였다.

• 한국초등과학교육학회지:초등과학교육
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• 제32권4호
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• pp.527-534
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• 2013

This study investigated elementary school teachers' understanding of the image formation by converging lens, pinholes camera, mirror and water. In each case teachers were asked to draw the ray diagram to indicate the position of the image. Teachers' ray diagrams were analyzed in accordance with the scientific process of image formation. Results of analysis showed that teacher's conceptions were classified into five levels for each situation. And most of the teachers were in level 3 and level 4 in each case. Because they had difficulties in the appling scientific conception(propagating path of light, diffused reflection from each object point, role of the eye, ray tracing) to finding location of image. Also most of teachers didn't know how to apply the law of reflection and refraction to each situation. The study finally discussed the teacher training program of the optical image.

• 한국전자파학회논문지
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• 제23권1호
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• pp.29-37
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• 2012

본 논문에서는 능동 위상 배열 안테나(APAA: Active-Phased Array Antenna)의 능동 반사 계수(ARC: Active Reflection Coefficient) 개선 및 보호 회로 구성을 통한 안정적인 시스템 운용에 관하여 연구하였다. 수동 위상배열 안테나에서와 달리 APAA는 복사 소자와 송수신 모듈이 결합된 형태로 일반적인 수동 위상 배열 안테나의 반사 계수 특성과 차별된 새로운 ARC의 정의가 적용되어야 한다. ARC는 방사하는 소자로부터의 자기 반사계수 외에 인접한 방사 소자로부터 유기되는 결합량의 중첩을 고려한 반사 계수이다. 이는 능동 위상 배열 레이더(APAR: Active-Phased Array Radar) 시스템의 특성을 예측하고 분석하는데 중요한 파라미터가 된다. 운용 중 발생하는 높은 ARC는 시스템 성능 열화에 직접적인 원인이 된다. 본 논문에서는 APAR의 안정적인 운용을 위한 방안으로 ARC의 성능을 개선시키는 방안과 보호 회로를 통한 열화 방지 방안에 관하여 분석하였다. 실제 제작한 능동 위상 배열 안테나의 실험 결과를 통해 두 방안의 유효성을 검증하였다.