• 한국학교수학회논문집
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• 제7권2호
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• pp.67-79
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• 2004

교육/학습의 질이 실질적으로 향상되려면 연구가 교육 현장과 밀접하게 연계되어 실천 가능한 지식, 도구, 기술 등을 제공하여 주어야 한다. 실천적인 활용을 최우선으로 하는 설계-실험 연구의 다양한 연구 방법, 원칙, 주제 , 활동 내용 그리고 주요한 특징, 연구 사례 등을 소개한다.

• 아동학회지
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• 제31권5호
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• pp.131-149
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• 2010

The purpose of this study was to examine research trends in articles of preschooler peer relationships carried in domestic academic journals. This was done in an attempt to suggest alternative directions for peer relationship studies in the early childhood education sector and lay the foundation for future studies. 131 articles that appeared in seven domestic academic journals related to early childhood education were selected and analyzed in order to better understand the general trends in the filed and the specific trends in terms of their content and methods. Our results indicate that the observation method was most common in the quantitative studies, and participant observation was most prevailent among qualitative studies. As for instrumentation, international instruments were most widely utilized, and the most dominant analysis method was descriptive statistics. In terms of reliability, internal consistency was checked most often, however, the majority of the studies failed to provide any information on validity and post-hoc analysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2640-2642
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• 2002

In this paper, we show the channel characteristics measurement system the frequency range up to 30MHz for medium voltage Power Line Grid. Power line channel characteristics are investigated by means of various measurement instruments. Measurement system consists of medium voltage coupler, impedance measurement part, noise measurement part, voltage sensing part and communication part. Measured data will be used for PLC channel modeling and PLC network system design.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.259-260
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• 2008

In this paper, we fabricated elastomer epoxy specimens by added liquid elastomer to improve the mechanical and electrical properties instead of previous high-voltage epoxy materials. As increased additive contents, glass transient temperature (Tg) was continually decreased in DSC (differential scanning calorimetry). Among specimens, 15 phr sample showed the mechanical and electrical properties similar of high-voltage epoxy in modulus, break-down and arc test. From the optimized condition of elastic epoxy, we confirmed a chance of application for high-voltage materials and power electrical instruments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.2135-2137
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• 2000

Usually arc phenomena are not easily characterized due to unstable behavior very short existence-times, high temperature and the required isolation of measurement instruments. This paper presents some arc-behaviors in a rotary arc gap-switch(RAG) using a 500kJ capacitor bank. It includes the speed variations of the rotating arc, the impacts of the oscillating current on the arc initiations and re-ignitions. Changes in the arc-dimension with respect to time and current magnitudes are also analyzed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2172-2174
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• 2001

Induction motors are a critical component of many industrial machines and are frequently integrated in commercial equipment. The many economical losses and the deterioration of system reliability might be caused by the failure of induction motors in industrial field. Based on the reliability and cost competitiveness of driving system (motors), the faults detection and diagnosis of system is considered very important factors. In order to perform the faults detection and diagnosis of motors, the vibration monitoring method and motor current signature analysis (MCSA) method are emphasized. In this paper, MCSA method is used for induction motor fault diagnosis. This method analyzes the motor's supply current, since this diagnoses the motor's condition. The diagnostic system is constructed by using LabVIEW of National Instruments.

• 한국엔터테인먼트산업학회논문지
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• 제14권6호
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• pp.151-160
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• 2020

클래식 음악은 '작곡가가 쓴 그대로 연주해야 한다'란 엄격함이 존재했다. 그러나 다양한 개성과 사고를 중시하는 21세기 포스트모더니즘 시대에 들어서면서 전통 클래식 무대를 제외하곤 그 엄격함의 무게가 더 이상 유의미하지 않게 되었다. 클래식의 기품은 간직한 채 엄격한 규칙대신 대중음악의 친숙함을 접목시키며 크로스오버 된 오페라 아리아는 그 동안 어렵게만 느껴졌던 오페라 아리아가 대중들에게 한층 쉽게 다가가며 클래식의 대중화를 이끌어내는 큰 역할을 하게 되었다. 그럼에도 불구하고 클래식 음악을 크로스오버 음악으로 탈바꿈시키는 편곡기법에 관한 연구는 부족한 상황이다. 따라서 본 연구는 객관적 음악분석 방법인 화성, 리듬, 악기 편성 중심으로 기존 선행연구의 연구범위를 확대한 오페라에 대한 크로스오버적 편곡기법을 연구하였다. 분석결과, 원곡과 팝페라 버전은 리듬, 화성에는 유사성을 보이고 있으나 악기 편성에서는 차이점을 보이고 있다. 재즈 버전은 아프로큐반 리듬의 발라드 계열인 볼레로 리듬, 재즈 어쿠스틱 악기 중심의 구성, Tension을 많이 사용한 Voicing을 통해 클래식컬한 느낌을 없애고 재즈의 느낌으로 연출하여 원곡과의 차별을 보이고 있는 것이 특징이었다. 본 연구가 클래식컬 크로스오버 편곡기법 연구 자료로서 유용하게 쓰이길 바란다.

• The Journal of Advanced Prosthodontics
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• 제8권3호
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• pp.224-228
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• 2016

PURPOSE. This study aimed to investigate whether dentin surface preparation with diamond rotary instruments of different grit sizes affects the shear bond strength of resin-bonded restorations. MATERIALS AND METHODS. The buccal enamel of 60 maxillary central incisors was removed with a low speed diamond saw and wet ground with silicon carbide papers. The polished surfaces of the teeth were prepared with four groups of rotary diamond burs with super-coarse (SC), coarse (C), medium (M), and fine (F) grit sizes. Following surface preparation, 60 restorations were casted with nickel-chromium alloy and bonded with Panavia cement. To assess the shear bond strength, the samples were mounted on a universal testing machine and an axial load was applied along the cement-restoration interface at the crosshead speed of 0.5 mm/min. The acquired data was analyzed with one way ANOVA and Tukey post hoc test (${\alpha}=.05$). RESULTS. The $mean{\pm}SD$ shear bond strengths (in MPa) of the study groups were $17.75{\pm}1.41$ for SC, $13.82{\pm}1.13$ for C, $10.40{\pm}1.45$ for M, and $7.13{\pm}1.18$ for F. Statistical analysis revealed the significant difference among the study groups such that the value for group SC was significantly higher than that for group F (P<.001). CONCLUSION. Dentin surface roughness created by diamond burs of different grit sizes considerably influences the shear bond strength of resin bonded restorations.

• 비파괴검사학회지
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• 제25권4호
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• pp.254-261
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• 2005

지금까지 한국인의 치아 통계는 매우 부족한 상태이고, 대부분 치아형태의 정보를 얻기 위해 방사선학적 방법을 이용하거나, 치아를 절단하는 등의 방법으로 연구를 해왔다. 이와 같은 방법은 오랜 시험 기간을 필요로 하고 정밀도가 낮고 파괴적인 방법을 주로 이용한 것이므로, 이제는 한국인의 표준 치아에 대한 정밀한 데이터를 얻기 위해 새로운 비파괴적인 시험이 필요하다. 이를 위하여 각각의 하악 제1소구치를 미세단층촬영기(Micro-CT, SkyScan, Belgium)를 이용하여 $21.31{\mu}m$의 해상도로 교합면에 대한 수평면으로 0.022mm 로 Scan을 하였다. 이를 통하여 내 외부 형태학적 중요부위를 측정하였으며, 영구 치아의 평균 치수표로 사용했었던 G. V. Black(1836-1915)에 의해 제시된 수치와 비교하였다.

• 한국환경과학회지
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• 제13권4호
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• pp.339-347
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• 2004

This paper asks the question: what choice of environmental policy instruments is efficient to reduce sulfur dioxide from stationary sources\ulcorner: In Korea, command and control has been a common way of controlling $SO_2-emissions.$ When compared to the non-incentive environmental policy instrument such as command and control, economic incentive environmental policy instrument has been the advantage of making polluter himself flexibly deals with in marginal abatement cost to develop environmental technology in the long view. Therefore, the application possibility of the incentive environmental policy instrument was studied in this research to realize the countermeasure for controlling of $SO_2-emissions.$ As a result, enforcement of the countermeasure such as flue gas desulfurizer by command and control would be suitable because power generation is performed by the public or for the public in source of air pollution and thus, economic principle is not applied to the polluter. In the source of industrial pollution, enforcement of fuel tax is found to be suitable for the countermeasure for the use of low sulfur oil in terms of the flexibility of demand for the price in the long tenn. For the permissible air pollution standards applicable to all air pollutant emitting facilities, enforcement of incentive environmental policy such as bubble, off-set, banking policy or tradeable emission penn its would be ideal in long terms according to the regional characteristics and the number and scale of air pollutant emitting facilities.