• 센서학회지
• /
• 제20권4호
• /
• pp.266-271
• /
• 2011

A reflection-type fiber-optic pH sensor, which is composed of a pH sol-gel film, plastic optical fibers, a mirror, a light source and a spectrometer, is developed in this study. As pH indicators, a bromthymol blue, a cresol red and a thymol blue are used, and they are immobilized in the sol-gel films. The emitted light from a light source is guided by a fiber-optic Y-coupler and plastic optical fibers to the pH sol-gel film in a pH sensing probe. The pH change in the sensing probe gives rise to a change in the color of the pH sol-gel film, and the optical characteristic of reflected light through the pH sol-gel film is also changed. Therefore, we have measured the spectra of reflected lights, which are changed according to the color variations of the pH sol-gel films with different pH values, by using of a spectrometer. Also, the relationships between the pH values and the intensities of reflected lights are obtained on the basis of the color variations of the pH sol-gel films.

• 대한지구과학교육학회지
• /
• 제14권2호
• /
• pp.159-172
• /
• 2021

이 연구는 온라인 과학 수업에서 실험 활동과 상호작용의 개선을 위한 수업 전략을 계획하고 그 결과를 바탕으로 개선 방안을 제시한 실행연구이다. 이를 위해 2020년 7월7일부터 9월 9일까지 G광역시에 위치한 초등학교 6학년 학생 20명을 대상으로 '지구와 달' 단원 수업을 실행하였다. 수업을 위해 실험 활동 범주에서 스마트 기기와 대체 실험, 상호작용 범주에서 온라인 대화방과 질의응답 전략을 계획하였다. 수집한 자료 중 수업 활동지, 과제물, 성찰 일지, 온라인 대화 내용, 질의응답 내용을 주요 자료로 하여 매트릭스에 입력하고 분석적 텍스트를 작성하여 그 의미를 분석하였다. 실행 결과 스마트 기기와 대체 실험은 탐구의 기회를 제공하였으나 오개념 형성에 대한 위험이 있었고 실험 활동을 방해하기도 하였다. 온라인 대화방과 질의응답은 소통의 기회와 과학 개념의 점검과 피드백 기회를 제공하였다. 본 실행연구를 통해 연구자는 수업 반성 노트를 작성하며 수업을 반성할 수 있었고, 과학 수업의 효과성과 효율성 측면에서 스마트 기기의 역할을 제안하였다.

• 한국자연치유학회지
• /
• 제12권2호
• /
• pp.45-55
• /
• 2023

배경: 음악적 자기돌봄 프로그램은 아동양육시설 생활지도원의 신체적, 심리적 소진을 예방하는 데 활용될 수 있다. 목적: 이 연구는 아동양육시설 생활지도원의 음악적 자기돌봄의 경험과 그 의미를 고찰하고자 질적 사례연구 방법을 적용하여 탐색하였다. 방법: 아동양육시설 생활지도원 4명을 대상으로 2022년 4월부터 2022년 6월까지 5회기의 음악적 자기돌봄 프로그램과 1회기의 심층 면담으로 진행하였다. 자료수집은 음악적 자기돌봄 프로그램과 심층 면담의 전 회기를 녹취하여 전사 자료로 수집하고 수집된 자료를 통해 집합적 사례연구로 분석하여 결과를 도출하였다. 결과: 음악적 자기돌봄을 경험한 연구참여자들의 돌봄 경험을 크게 두 가지의 관점으로 확인하였다. 첫번째는 돌봄 과정에서의 성찰, 두 번째 결과는 돌봄 과정에서의 음악 활용의 유익함이다. 결과를 통해 아동양육시설 생활지도원의 자기돌봄의 필요성을 확인하고, 자기돌봄의 다양한 방식 중 음악을 활용한 자기돌봄 과정이 긍정적인 효과가 있음을 확인할 수 있었다. 결론: 음악적 자기돌봄 과정에서 음악의 개입이 개인의 자기성찰과 자기수용을 바탕으로 하며 동료 간의 소통을 통해 심리적 보상을 얻고, 심리적 회복을 도와 상호협력적인 관계를 형성하도록 하였다. 본 연구는 아동양육시설 생활지도원에게 음악적 자기돌봄의 필요성을 나타내고 사회복지 현장에서 적용되는 사례가 중요하다는 시사점을 제공한다.

• 대한방사선기술학회지:방사선기술과학
• /
• 제31권1호
• /
• pp.55-60
• /
• 2008

목적: 판독용 모니터의 성능을 평가하는데 있어 불필요한 시간 및 인력 등을 줄이고 판독의 최적화 유지와 모니터의 upgrade 시기, 그리고 교체 시기를 결정할 수 있는 시스템을 구축하는데 필요한 적절한 수준의, 일정기간의 성능평가 관리 주기 및 calibration 주기를 결정하고자 하였다. 대상 및 방법: 판독용 LCD 컬러 모니터(CCL350i, Totoku, Japan) 20대를 대상으로 2007년 3월부터 8월(첫 calibration 후 3, 4, 5, 6, 7, 8개월째)까지 매달 1회에 걸쳐 한 달 주기로 총 6회의 성능 평가를 하였다. 성능 평가에 사용된 측정 도구는 휘도계(DTP 94 39630, X-Rite Inc. U.S.A.)와 조도계(LX-101 Q031871, Lutron, U.S.A.) 그리고 모니터 성능관리 프로그램인 AAPM TG 18 protocol를 이용하였다. 성능평가 항목은 기하학적 왜곡(geometric distortion), 반사 테스트(reflection test), 휘도 반응 평가(luminance response evaluation), 휘도 균일도(luminance uniformity), 분해능(resolution), 노이즈(noise), 베이링 그레어(veiling glare), 색도(chromaticity) 등 8개 항목을 포함하였다. 결과: 기하학적 왜곡 평가와 반사 테스트, 휘도 균일도 테스트, 분해능, 노이즈 평가, 베이링 그레어 테스트, 색도 테스트 등은 AAPM TG 18에서 권고하는 기준치에 모두 부합되었다. 휘도반응평가 중 예측되는 최대 휘도와 관측되는 휘도의 편차 항목에서 4개월째부터 25%(4대)의 모니터가 8개월째까지 기준 편차를 벗어나기 시작하였으며, 8개월째에는 다른 모니터 7대에서도 편차를 보이기 시작하여 전체적으로 55%(11대)의 모니터에서 기준 편차를 벗어나고 있었다. 또한 대조도 반응의 편차 항목에서 4개월째부터 예측되는 최대 휘도와 관측되는 휘도의 편차의 기준치를 벗어나기 시작한 4대의 모니터 중 5%(1대)에서 4개월째부터 8개월째까지, 또다른 2대는 8개월째부터 편차를 보여 전체적으로 8개월째에는 15%(3대)의 모니터에서 기준 편차를 벗어났다. 결론: 성능평가의 주기는 calibration 후 4개월째부터 오차 범위를 벗어나는 결과와 모니터 수 그리고 성능 검사에 소요되는 인력 및 시간을 고려할 때 3개월에 한번씩 평가함이 효율적이라고 판단된다. 또한 calibration 주기는 8개월째부터 50% 이상에서 편차를 보인 결과 및 성능평가 주기를 고려할 때 calibration 후 6개월을 주기로 calibration을 다시 시행하여야 할 것으로 판단된다.

• 한국전기전자재료학회논문지
• /
• 제28권5호
• /
• pp.306-313
• /
• 2015

In this study, the change of optical characteristics was studied according to the micro optical pattern provided by photo lithography followed by thermal reflow process. The shape and luminance variation with micro pattern was evaluated by SEM and spectrometers. Also, we analyzed the luminance characteristics using the 3D-optical simulation (Optis works) program. As a result, we found that the radius of curvature(R) in micro pattern is decreased up to 77%($150^{\circ}C$) compared to the radius of curvature at the condition $100^{\circ}C$, which is caused by efficient reflow of organic material without chemical changes. The highest enhancement of brightness with optimum micro pattern was obtained at the condition of $120^{\circ}C$ reflow process. The brightness gain with optical micro patterns is more than 15% at the condition of R=16.95 um, ${\Theta}=77.14^{\circ}$ compared to original optical source. The results of light simulation with various radius of curvature and side angle of pattern shows the similar result of experiment evaluation of light behavior on optical micro patterns. It is regarded that the more effect on light enhancement was contributed by side angle which is effective factor on light reflection, rather than the curvature of micro-patterns.

• 한국정밀공학회지
• /
• 제32권10호
• /
• pp.897-902
• /
• 2015

This study reports on a uniform resin coating method by using a doctor blade type dispenser. For high productivity, continuous imprint-lithography has been studied, and developed fabrication systems are used in several applications such as anti-reflection films, dry adhesives, and water collecting surfaces. In the continuous fabrication field, researchers have typically focused on patterning and demolding procedures. During the roll-to-roll fabrication process, however, the uniform resin coating process is also important in order to obtain a high quality product, which can be evaluated by uniform thickness, precise geometric expressions, and a thin residual layer. To achieve these, a doctor blade type dispenser was designed and fabricated. As a result, thickness of coated resin was well controlled by modulating the flow rate of the resin and blading gap. In addition, a very thin layer coating process (${\sim}10{\mu}m$) was achieved by softly contacting the blade on the substrate.

• 한국운동역학회지
• /
• 제17권2호
• /
• pp.167-176
• /
• 2007

The purpose of this study was to offer suitable model for performing Tippelt motion and data for training Tippelt motion through the quantitative kinematical analysis of Tippelt motion in parallel bars. The results of analysing kinematic variations through three-dimensional reflection analysis of three members of the national team as the objects of the study were shown as follows. 1. It seemed that the shoulder-joints which are stretched as much as possible affects the whole Tippelt motion while one is swinging downward. The time of process of the center of mass for the body reaching to the maximum flection point should be quick and body's moving from the vertical phase to the front direction should be controled as much as possible. 2. While one is swinging upward, the stability of flying motion could be made certain by the control of body's rapid moving to the front direction and stretching shoulder-joints and hip-joint to reverse direction. 3. While one is flying upward, the body should be erected quickly and lessening the angle of the hip-joint affects the elevation of flight. When the powerful counter turn motion is performed, the stable motion could be made. As a result of this study, It seems that sudden fall and the maximum stretch of shoulder-joints is important during performing Tippelt motion in parallel bars. Also, it concludes that the maximum bending of hip-joints at the starting point of upward swing, sudden stretch to the reverse direction of shoulder-joints and hip-joints when one is leaving bars, control of body's moving to the front direction, and lessening the angle of hip-joints at the flying phase is important.

• 천문학회지
• /
• 제36권spc1호
• /
• pp.83-91
• /
• 2003

There are terrestrial signatures of the solar activity cycle in ice core data (Ram & Stoltz 1999), but the variations in the sun's irradiance over the cycle seem too small to account for the signature (Lean 1997; Goode & Dziembowski 2003). Thus, one would expect that the signature must arise from an indirect effect(s) of solar activity. Such an indirect effect would be expected to manifest itself in the earth's reflectance. Further, the earth's climate depends directly on the albedo. Continuous observations of the earthshine have been carried out from Big Bear Solar Observatory since December 1998, with some more sporadic measurements made during the years 1994 and 1995. We have determined the annual albedos both from our observations and from simulations utilizing the Earth Radiation Budget Experiment (ERBE) scene model and various datasets for the cloud cover, as well as snow and ice cover. With these, we look for inter-annual and longer-term changes in the earth's total reflectance, or Bond albedo. We find that both our observations and simulations indicate that the albedo was significantly higher during 1994-1995 (activity minimum) than for the more recent period covering 1999-2001 (activity maximum). However, the sizes of the changes seem somewhat discrepant. Possible indirect solar influences on the earth's Bond albedo are discussed to emphasize that our earthshine data are already sufficiently precise to detect, if they occur, any meaningful changes in the earth's reflectance. Still greater precision will occur as we expand our single site observations to a global network.

• 한국가구학회지
• /
• 제20권4호
• /
• pp.358-373
• /
• 2009

Probability based design(PBD)method has some advantages against current design methods. First, it can provide the quantitative values for the structural safety or capacity through the reliability index, $^{\beta}$. That presented the certainty on the corresponding structure for the designer or user, also that permitted the broad consideration in the safety of structures. In addition, it can give the quantitative lifetime of the related structure in the calculation process of target reliability index. Also, incidental economical efficiency can be expected because decrease of required structural material can be obtained by using the practical material data. Unlikely current deterministic structural design methods, main advantage is the reflection of real condition in the structural design process by application of the data with not small clear specimen but structural size material. Advanced countries, namely America, Canada, Europe, Australia and New Zealand already converted from allowable stress design(ASD) method to PBD method and used as a standard wooden structures code in the late 1980s and 1990s. Other domestic constructions standards such as the steel or concrete constructions accepted and used the PBD methods already. Accordingly, wooden structural design method also should be converted from deterministic ASD to probabilistic LRFD(Load and resistance factor design) in order to keep pace with worldwide demands for PBD. Hence, to suggest the reason of introduction the PBD in domestic wooden structural design and analysis, a brief example was used to show the different reliability index by using the different design methods. Definition, merits and demerits of deterministic ASD and probabilistic LRFD were followed. Also the three examples were presented to show the similarity and differences between ASD and LRFD. Finally, connection problems that might cause a disputation in wooden structural design and analysis were broadly examined.

• 대한원격탐사학회지
• /
• 제27권6호
• /
• pp.677-692
• /
• 2011

Suspended sediment is an important oceanic variable for monitoring changes in coastal environment related to physical and biogeochemical processes. In order to estimate suspended sediment concentration (SSC) from satellite data, we derived SSC coefficients by fitting satellite remote sensing reflectances to in-situ suspended sediment measurements. To collect in-situ suspended sediment, we conducted ship cruises at 16 different locations three times for the periods of Sep.-November 2009 and Jul. 2010 at the passing time of Landsat $ETM_+$. Satellite data and in-situ data measured by spectroradiometers were converted to remote sensing reflectances ($R_{rs}$). Statistical approaches proved that the exponential formula using a single band of $R_{rs}$(565) was the most appropriate equation for the estimation of SSC in this study. Satellite suspended sediment using the newly-derived coefficients showed a good agreement with insitu suspended sediment with an Root Mean Square (RMS) error of 1-3 g/$m^3$. Satellite-observed SSCs tended to be overestimated at shallow depths due to bottom reflection presumably. This implies that the satellite-based SSCs should be carefully understood at the shallow coastal regions. Nevertheless, the satellite-derived SSCs based on the derived SSC coefficients, for the most cases, reasonably coincided with the pattern of in-situ suspended sediment measurements in the study region.