• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.16-22
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• 2008

on-line system for preconcentration and separation of lead(II) is presented. The method is based on the complex formation of Pb(II) with adsorbed Methyl thymol blue on activated carbon. The conditions of preparing the solid phase reagent and of quantitative recovery of Pb(II) from diluted solutions, such as acidity of aqueous phase, solid phase capacity, and flow variables were studied as well as effect of potential interfering ions. After preconcentration step, the metal ions are eluted automatically by 5 ml of 0.5 M HNO3 solution and the lead ions content was determined by flame atomic absorption spectrometry. Under the optimum conditions, the lead ions in aqueous samples were separated and preconcentrated about 1000-fold by the column. The detection limit was 0.001 g mL-1. Lead has been determined in river and tap water samples, with recovery of 98 to 102%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3412-3418
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• 2013

The Purpose of this study was to evaluate by comparing the dose change and build up characteristic according to delay time in 30 days of glass dosimeter processed preheat and non preheat when measuring accumulation dose of radiation by using glass dosimeter over the long haul. For obtaining low dose with 0.1 mGy, 1 mGy and 5 mGy, we employed diagnostic generator AccuRay-650R. We compared the build up characteristic over the long haul by exposuring radiation to 30 glass dosimeters sorted into 10 glass dosimeters per tube voltage and current. In Non preheat glass dosimeter, initial measured dose was inferior to exposed dose but as time goes on, was close to exposed dose steadily. In 72 hour after experiment end, non preheat glass dosimeters were not indicated the difference from preheat glass dosimeters and statistical analysis were meaningful (p>0.05). Initial measured dose for low glass dosimeter processed preheat was close to exposed dose and stable. After 15 days dose was gradually increased. Previous study characteristics of glass dosimeter were with respect to characteristic of glass dosimeter in high dose of high energy area. However, in this study, we make a judgment to measure the dose of glass dosimeter without preheat processing when measuring the accumulation dose of low dose in conclusion.

• 한국정보교육학회:학술대회논문집
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• 2004.01a
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• pp.458-467
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• 2004

본 연구 개발은 초등학교 예비 교사에게 국어과 ICT 교수 학습에 대한 이해와 과정안 개발 및 수업에서의 활용 능력을 길러주고, 아울러 향후 ICT를 활용한 국어과 교육을 교육과정에 반영할 경우 제기될 수 있는 문제점을 짚어보고 개선 방안을 모색하는 데 그 목적을 두었다. 연구 개발의 내용은 국어과 ICT 활용 교육 관련 문헌 및 자료 탐색, 자료 및 수업 운영 실태 분석, 국어과 국어과 6학년 1, 2학기 180차시에 대한 학습 내용 및 목표 분석과 국어과 6학년 1, 2학기 180차시에 대한 ICT 교수 학습 과정안 개발, ICT 교수 학습과정안 개발 결과물의 수정 검토 및 서버 탑재, ICT 교수 학습 과정 개발 과정의 교육과정 적용 방안 모색이다. 본 연구 개발을 위하여 2003년 2학기 강좌인 '국어과 교재 연구(2학점)'와 통합하여 교수 학습 과정안 개발을 추진하였다. 본 강좌에서는 과정안 개발에 필요한 모형 안내, 과정안 작성 방법 지도, ICT 활용 수업의 분석, 과정안 개발에 필요한 컴퓨터 소양 교육이 이루어졌으며 과정안의 개발은 학기 과제로 추진하였다. 본 연구 개발 과제의 수행을 통하여 최종적으로 국어과 6학년 ICT 교수 학습 과정안 180차시와 연구 보고서 1종을 산출하였다. 본 연구 개발의 성과는 다음과 같다. 첫째, 예비 교사에게 국어과 ICT 교수 학습 모형 및 과정안에 대한 이해를 높이고 교수 학습 과정안의 작성 능력을 길러주었다. 둘째, 연구 보고서에 제시된 국어과 ICT 자료 개발 및 활용 실태, 예비 교사의 ICT 교수 학습 과정안 개발을 위한 강의 계획과 개발을 위한 실제 지도 과정은 향후 관련 강의나 연구를 설계하고 교육과정을 마련하는 데 도움을 줄 수 있다. 셋째, 예비 교사들이 개발한 자료는 현장 교사들이 국어과 수업을 운용하는 데 활용할 수 있다. 본 연구 개발 결과 드러난 문제점과 보다 나은 연구와 강의를 지향하기 위한 개선 방안을 제시하여 보면 다음과 같다. 첫째, 예비 교사의 특성과 개발 내용에 비추어 볼 때 ICT 교수 학습 과정안 개발 기간이 짧았다. 따라서 강의 시수를 늘리는 방안, 관련 강좌를 추가로 개설하는 방안, 기존 강좌를 통합하여 운영하는 방안을 고려해 보아야 한다. 둘째, 예비 교사의 수준을 고려할 때 여러 가지 '부가 자료'를 포함하는 ICT 교수 학습 과정안을 1인 1차시씩 개발하도록 하는 것은 학생들에게 상당한 부담을 안겨 주었다. 대안으로는 개발 관련 강자를 1년 단위로 계획하여 운용하는 방법, 학생 4-5명 당 1차시씩 개발하도록 하는 방법, ICT 교수 학습 과정안 자체만 개발하고 학습지, 교사연구자료, 자율학습 자료 등은 생략하는 방법 등이 있다. 셋째, 학생들의 컴퓨터 소양 기능이 부족한 상태에서 ICT 교수 학습 과정안 개발을 과제로 부과할 경우 좋은 결과물을 기대할 수 없다. 따라서 현재 교육대학의 교육 과정 편성 체제를 감안하면 컴퓨터 강좌와 교과 교육 강좌를 통합 강좌 형태로 운영하는 방법을 고려해 볼 만하다. 넷째, 교수 학습 모형의 경직성과 실제 교수 학습 변인을 고려한 활용이나 변형에 대한 탐구가 여전히 부족했다는 점이다. 앞으로는 이를 몇 가지의 모형 틀 속으로 자꾸 끓어 내려고 하는 것보다는 기존의 모형을 다양하게 변형할 수 있도록 그 틀을 열어줄 필요가 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.418-430
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• 2017

This study examined the process, difficulties and understanding of making teaching materials by investigating the pre-service early childhood teachers' experience of making such materials. The results of the study would help in the design direction and methods of education for pre-service teachers in how to make materials. A total of 30 university students, who took the course of 'Early Childhood Educational Materials and Research Method' in B university, participated in the study. At the exploration stage, the pre-service teachers utilized the teacher guidance of Nuri curriculum, major books, internet materials, and their observation experiences in kindergartens. At the planning stage, they considered chiefly the children's interest and level, explored materials sufficiently, and selected the production method carefully. At the production stage, they performed basic hard work to prevent rework and tended to stick to the basics beyond their initial ambition as the work progressed. The difficulties that they faced, feeling pressured, were making materials based on their imagination without experiencing much from the infants, feeling embarrassed when things did not progress as planned, and feeling a sense of loss when comparing with other friends. Through these difficulties, the importance of precise planning, executing the process thoroughly, and repeatedly checking and reviewing the entire process of making textbooks and materials were realized. In addition, there is a need to search for a better development direction for the effective development of teaching textbooks and materials.

• Journal of the Korean earth science society
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• v.40 no.5
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• pp.538-547
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• 2019

This study analyzes the conceptual understanding of in-service and pre-service earth science teachers about the H-R diagrams and evolution of stars using conceptual status analysis categories. The results show that (a) many teachers use unscientific language in the Intelligibility range, (b) teachers are categorized in Low scientific inquiry ability related to graph creation and unscientific analogy for scientific concept which is hightly corelated to the possibility of misunderstanding in the teaching process, and (c) pre-service teachers lack the understanding of the secondary science curriculum. It is necessary to develop pre-service curriculum that can be applied to the school site. In the category of Plausibility range, (d) both groups understood the cosmological meaning of stellar evolution. However, pre-service teachers do not specifically explain the mechanism of a star. In the category of Fruitfulness range, in-service teachers come up with educational problems reflecting the academic characteristics of earth science and apply their knowledge to actual problem solving. On the other hand, pre-service teachers show high nonresponse ratio, they do not see the H-R diagram and the evolution of stars as a practical concept. In the analysis process, both groups are found to have many unscientific conceptions about the H-R diagram and evolution of stars. Therefore, it is suggested that caution be used in developing a professional development program of earth science teachers.

• Journal of Science Education
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• v.47 no.1
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• pp.52-62
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• 2023

This study examines how prospective earth science teachers perceive the concept of "equilibrium" and "interaction between Earth's spheres" in understanding Earth's radiative equilibrium and tries to identify their misconceptions. For this purpose, a questionnaire was designed and put to them to look into their thought flow based on the items that appeared in the national level evaluation. As a result of analyzing their answers, even though all the prospective teachers correctly described the concept of radiative equilibrium, about 90% of them did not apply the concept of radiative equilibrium to the new environment of the Earth without atmosphere. They do not seem to be able to smoothly derive the concept of a new 'interaction' between the changed regions and a new 'equilibrium' that will be reached over a long period of time. In this respect, it is likely that the textbooks had some influence on the formation of their concepts. In particular, high school Earth Science textbooks describe the Earth's radiation equilibrium in a quantitative manner, focusing on the heat budget of the equilibrium state rather than the process of reaching radiation equilibrium. Such an approach of textbooks might be an obstacle to fostering students into creative convergence-type talents pursued in the 2015 revised curriculum. Meanwhile, in order to eliminate the misconceptions of students often found in the understanding of Earth's radiation equilibrium, this study suggests that the core concepts need to be dealt with more attention even in college courses for training prospective teachers.

• International Area Studies Review
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• v.13 no.2
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• pp.66-88
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• 2009

This paper studies optimal discretionary monetary policy in the presence of uncertainty in the housing sector. In particular, we allow two possible regimes regarding the evolution of housing price inflation and the effects of housing price inflation on the aggregate demand. Estimation results with the US data confirm the presence of two distinctive regimes, one 'normal' and the other more akin to the housing price 'bubble' state. The optimal policy is 'asymmetric' in that the optimal responses in the 'normal' regime require the central bank to lean against the wind to inflationary pressure from CPI and housing inflation, while the central bank is recommended to accommodate it in the other regime.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.765-766
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• 2017

본 논문은 유럽의 Galileo 시스템에 대한 특성을 분석하고, 추진 계획된 30기의 위성(24+예비6) 중에서 현재까지 구축된 18기 위성으로 위치측정이 가능한지 기하학적 배치 상태를 확인하기 위하여 DOP를 분석하였다. 분석결과, 하루 24시간 중 17시간은 양호한 DOP로 정상적인 위치측정이 가능하였으며, 7시간은 위성 수가 3개로 부족하여 위치측정이 제한되었다.

• Journal of Music and Human Behavior
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• v.16 no.1
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• pp.25-46
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• 2019

This pilot study involved a single session of song-based music therapy to relieve the anxiety of intensive care unit (ICU) caregivers. Six caregivers of ICU patients participated in the intervention session individually. During the initial stage of the intervention, the participants' current emotional states were identified. Then they listened to familiar songs and playing a tone chime, which was intended to help them relax their body and reduce their psychological resistance. During singing experiences as an essential part of the intervention, the participants discussed the lyrics of songs in an attempt to find the meaning related to them. Also, they sang the songs with a live accompaniment in which their emotional states were reflected with changes in musical elements (e.g., tempo, dynamics, rhythm, or chords). In the final stage, they identified personal application to their everyday lives. To analyze the results, the State-Trait Anxiety Inventory (STAI) and a visual analog scale on emotional states were completed by participants before and after the session, and participants' verbal responses during the session were also recorded. According to the results, STAI anxiety scores significantly declined following the session. Also, they showed significant increases in positive emotions and significant decreases in negative emotions. This suggests that short-term music therapy can be an effective intervention for relieving the psychological distress of ICU caregivers.

• Water for future
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• v.26 no.2
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• pp.99-105
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• 1993

A practical flood forecasting model(FFM) is suggested. The output of the model is the results which the initial condition of meteorological parameters and soil moisture are projected on the future. The physically based station model for rainfall forecasting(RF) and the storage function model for runoff prediction(RP) are adopted respectively. Input variables for FFM are air temperature, pressure, and dew-point temperature at the ground level and the flow at the rising limb(FRL). The constant parameters for FFM are average of optimum values which the past storm events have. Also loss rate of rainfall can predicted by FRL.