• Korean Journal of Pharmacognosy
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• v.45 no.2
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• pp.135-140
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• 2014

A simple and reliable reverse phase HPLC method was developed to determine pharmacologically active marker compounds of Epimedii Herba, Atractylodis Rhizoma Alba, and Polygalae Radix. The stability test of water-extracts of the three natural medicines has been evaluated for six months. However, no significant changes in the content of the marker compounds of each extract were observed during the time of investigation.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.37.1-37.1
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• 2010

망원경을 사용하여 천체를 관측할 때, 관측할 천체가 있는 위치로 망원경을 정확히 구동하여야 하고, 관측하는 시간 동안 충분히 정확히 추적하여야 한다. 그러나, 망원경은 다양한 재질의 많은 종류의 기계적인 부품들을 조립하여 만들어져 있기에, 필연적으로 기계적인 오차를 가지고 있다. 망원경 구동제어 장치는 수학 연산과 다양한 펄스 특성에 기인한 제어 오차를 가지고 있다. 그리고, 영상을 획득하는 부분은 시간 지연과 상의 왜곡이나 전자적인 잡음의 영향을 받는다. 또한, 바람이나 진동 등 예기치 않은 외부적인 요인에 의한 오차가 유발되기도 한다. 이러한 다양한 요인들로 인하여, 망원경이 천체를 정확히 찾아가고 추적하는 것을 어렵게 만든다. 우리는 자동제어공학에서 사용하는 제어해석 기법을 사용하여 망원경 제어 모형을 만들어 나가고자 한다. 특정 망원경에 있어, 오차 유발에 어느 요인이 가장 큰 영향을 주는지, 또한, 어떤 특성을 조절하고, 어느 정도의 제어 시간 간격을 주어야 하는지 등, 추적오차에 주는 영향들을 정량적으로 분석하고 제어에 반영하여 가장 최적의 제어를 할 수 있도록 하고자 한다. 그 첫번째 시도로, 김해천문대 독일식 적도의 방식 200mm 망원경과 이전 연구에서 개발한 PLC 기반의 망원경 제어 장치(강용우 외, 2008) 및 AP8 CCD 카메라를 사용하여, 지향 및 추적 관측 실험을 하였다. 그 결과를 분석하여 경험적 제어 모형을 만들고, 그 해석을 수행한 내용을 소개하고자 한다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.5
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• pp.627-633
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• 2001

Characteristics of a diesel spray impingement with the variation of ambient temperature, wall temperature and ambient pressure were investigated through shadowgraphy method by using high speed camera. The radial penetration of spray was increased with ambient temperature and wall temperature. It is resulted from the decrease of ambient gas density caused by the increase of temperature. The height of spray was also increased with ambient temperature and wall temperature, because the height of stagnate region is noticeably increased, although height of wall jet vortex is decreased. At the same ambient pressure, the area ratio of impinging spray of room temperature environment to high temperature environment was increased, as the temperature difference between room temperature and high temperature increases. And the increment of area ratio was higher at low ambient pressure than high ambient pressure.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.93.2-93.2
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• 2012

연료전지는 전기화학반응을 이용한 발전 장치로서 기존 장치에 비하여 발전 효율이 높아 화석연료를 사용하면서 현재 당면 과제인 $CO_2$ 배출량 절감이 가능하고, 환경 보전성이 우수하여 미래의 전원으로 많은 연구개발이 진행되고 있다. 특히 제3세대 연료전지라 불리는 고체산화물 연료전지(Solid Oxide Fuel Cell이하 SOFC)는 고가의 외부 개질 장치 없이도 연료가 갖는 화학에너지를 연소과정 없이, 공기와 $H_2$, CO, $CH_4$와 같은 환원성 가스를 공급받아 $600{\sim}1000^{\circ}C$에서 전기화학적 반응을 통하여 직접 전기를 얻는 방식이며, 낮은 소음과 진동으로 인하여 온 사이트(On-site) 발전이 가능한 장점이 있는 연료전지이다. Decalcomanie는 전사용지에 Screen printing하여 건조 후 coating하는 방법으로 기존의 여러 coating 방법보다 다전지셀 제작이나 Buffer layer의 적용이 용이하고, 소재의 크기나 두께조절이 간편하며, 구성층의 표면조도나 굴곡에 대응이 용이한 방법이다. 새로운 Decalcomanie를 사용하여 평관형 다전지식 SOFC Cell 제작 및 각 Buffer layer에 적용, Screen printing법과 동일한 Cell 제조 후 MPD와 Impedance 분석을 통하여 Support 위에 전사지를 이용, 적층한 Cell의 전기화학적 특성에 관하여 분석하였다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.217-220
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• 2005

햄버거 패티에 기능적 특성을 부여하고자 실크 펩타이드를 첨가하여 햄버거 패티를 제조한 후 품질특성 및 최적 실크 펩타이드 첨가량을 평가하였다. 실크 펩타이드가 햄버거 패티의 가열 감량에 미치는 영향을 분석한 결과 실크 펩타이드 첨가량이 증가함에 따라 가열감량이 유의적으로 감소하는 것으로 나타났다. 실크 펩타이드가 첨가된 햄버거 패티의 경도, 탄성 및 점착성을 분석한 결과 경도는 실크 펩타이드 첨가량이 증가함에 따라 감소하는 경향이었으나, 탄성과 점착성의 경우 실크 펩타이드 첨가에 의해 영향을 받지 않는 것으로 나타났다. 또한, 색도 측정결과 실크 펩타이드 첨가량이 증가함에 따라 명도(L) 및 적색도(a)는 유의적으로 증가하였으며, 황색도(b)는 감소하는 것으로 나타났다. 실크 펩타이드를 첨가한 햄버거 패티의 관능적 특성을 분석한 결과 실크 펩타이드가 첨가된 햄버거 패티는 외관, 후각, 미각, 조직감 및 종합적 기호도 등 모든 평가항목에서 무첨가구에 비해 높게 나타났다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.252-257
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• 2011

A compact microstrip dual-band bandpass filter with controllable bandwidth for each passband is proposed. Each passband is independently designed using two different dual-mode resonators. The proposed dual-band bandpass filter has three transmission zeros. Two transmission zeros are generated by each dual-mode resonator. An additional transmission zero is generated by input/output port coupling. The dual-band bandpass filter application is designed for 2.4/5.7 GHz WLAN. Experimental results are presented to validate theory.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.400-407
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• 2010

Zoysiagrass (Zoysia japonica Steud.), also called Korean or Japanese lawngrass, is the most popular warm-season turfgrass in Korea and is widely used for home lawns, parks, roadsides, golf courses and athletic fields. Its use is rapidly expanding in Korea and the other countries, due to its excellent characteristics which include tolerance to heat, drought and salinity. As the utilization area of this turfgrass increases, there is an increase in the demand for improved cultivars with disease and insect tolerance or with herbicide-tolerance or with extended greening periods. Conventional breeding methods have been used to improve the traits described above with limited success. However, with the advances in biotechnology, genetic transformation can be utilized for turfgrass improvement. In this paper, we review recent progress in biotechnological improvement of zoysiagrass and discuss future molecular breeding of this species.

• Journal of Child Welfare and Development
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• v.16 no.2
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• pp.67-85
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• 2018

The purpose of this study was to analyze the trends in the studies on safety education of infant-early childhood teachers in order to provide basic data for a variety of studies in the field of child education. We consulted a total of 59 dissertations and journals articles on the safety education of infant-early childhood teachers published from 2008 to 2018. Our results were as follows: First, we found that the largest number of studies concerned safety awareness, followed by status and awareness, safety actions, safety education analysis, safety accidents and countermeasures, emergencies, development of programs, and teacher education. Second, we found that the most popular targets were child-care of teachers, followed by teacher-trainees, and center directors. Third, among the types of studies, we found that investigative quantitative studies were the most prevalent, followed by correlational studies, qualitative studies, and experimental studies. In terms of methods of gathering data, we found that questionnaires were the most commonly used, followed by qualitative studies, literature reviews, qualitative/quantitative studies, and quantitative literature reviews.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.2
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• pp.221-238
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• 2002

Purpose: The purpose of this study was to develop and test the validity of the standardized Korean nomenclature of 260 Nursing Outcomes Classification(NOC) developed by Johnson and Mass at University of Iowa in 2000. Method: The four phases of the study were: (1) translation of the NOC into Korean by the Research Team, (2) nine nursing professors and nurses with various clinical backgrounds reviewed each nomenclature taking into consideration of definitions and outcome indicators. The modified Delphi method was used to determine the most appropriate nomenclature for each term, (3) 307 Clinical expert nurses more than three years field experiences were given a questionnaire to rate each Korean nomenclature using a 5 point Likert scale ranging from very inappropriate to very appropriate, and (4) final accordance of Korean Nomenclature. Result: The team determined that 260 Korean nomenclature was appropriately named. because the mean validity score of 260 outcomes was 3.90 and each of 260 Korean nomenclature had a score more than 3.00. Conclusion: Korean nomenclature of NOC can be used as a standardized language of nursing result in a computerized nursing information system.

• Mycobiology
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• v.33 no.1
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• pp.15-18
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• 2005

Macrolepiota procera, one of edible mushrooms belongs to Agaricaceae of Basidiomycota, has a good taste and good medicinal value. As a preliminary study for the development of artificial cultivation method of edible mushroom, cultural characteristics of M. procera was investigated on various culture media under different environmental conditions. Mycelial growth was compared on culture media composed of various carbon and nitrogen sources, and C/N ratios. The optimal conditions for the mycelial growth were $30^{\circ}C$ and pH 7. M. procera showed the rapid mycelial growth in the PDA media. The optimal carbon and nitrogen sources were maltose and glycine, respectively. The optimum C/N ratio was about 10 : 1 in case that 1% glucose was supplemented to the basal media as carbon source.