• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.427-427
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• 2010

전색 디스플레이의 배경조명과 일반조명으로 응용 가능한 백색 유기발광소자를 제작하기 위해서는 삼원색을 혼합하는 방법과 단색광원의 색변환을 이용하는 방법등이 제안되었다. 삼원색을 혼합하는 방법의 연구가 접근방법 및 효율개선이 용이하기 때문에 많은 연구가 진행되어왔다. 그러나 색변환 방법을 사용하는 구조는 삼원색을 혼합하는 방법에 비해 공정이 단순하며 공정 가격이 낮아지고 안정적인 구조라는 장점이 있기에, 본 연구에서는 무기물 형광체를 청색유기발광 소자에 결합하여 제작된 백색 유기발광소자의 전기적 성질과 광학적 성질을 규명하는 연구를 진행하였다. 본 연구에서는 나노크기의 균일한 형광체를 제작 할 수 있는 졸겔 방법으로 적색 형광체를 제작하였다. 졸겔 방법으로 제작된 형광체에 대한 주사현미경 측정 결과 입자의 표면이 고르며 크기가 작고 균일 하였고, 높은 온도 열처리에 따라서 용매제가 대부분 제거되었기 때문에 형광체 발광 특성이 잘 일어났음을 확인 할 수 있었다. 제작된 형광체의 광학적 성질을 조사하기 위해 형광 루미네센스 측정을 하여 발광특성을 분석하였으며 실제 청색 유기발광소자에 적용하기 위해 tris((3,5-difluoro-4-cyanophenyl)pyridine)iridium (FCNIr)-doped 3,5-bis (N-carbazolyl) benzene (mCP)를 발광층으로 사용하는 진청색의 인광 유기발광소자 배면에 무기물 형광체를 결합하여 인가한 전압에 따른 전계발광분광특성의 변화를 조사하였다. 유기발광소자와 결합된 적색 무기물 형광체는 진청색 인광 유기발광소자에서 발광된 청색빛의 일부를 흡수하여 적색으로 색변환을 하였고 이는 무기물 형광체내에 첨가된 Mn 원자에 의해 색변환이 이루어졌음을 확인하였다. 무기물 형광체를 사용한 백색 유기발광소자의 색변환 메카니즘 및 효율 증진에 대한 연구는 고효율 유기발광소자 제작을 가능하게 할 것이다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.938-940
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• 2003

고출력 반도체 레이저(500mW)의 출력광 파장 809nm과 반도체 레이저로 여기되는 Nd:YVO4레이저의 출력광 파장 1064nm를 공진기 내부에서 비선형 광학 소자인 KTP(Potassium titanyl posphate : KTPiOPO$_4$)를 사용하여 합주파 발생 실험을 행하여 459nm의 청색레이저를 얻었다. 제2의 위상 정합 정합조건($\psi$=90$^{\circ}$, $\theta$=90$^{\circ}$)에서 반도체 레이저의 입력광 세기가 400mW일 때 청색레이저의 최대 출력 0.95mW를 얻었으며, 청색레이저의 발진문턱입력 세기는 120mW이었다.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1733-1735
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• 2000

평판 디스플레이 소자인 후막 전계발광소자는 평판형 조명부터 LCD 백라이트에 응용되고 있다. 후막 전계발광소자에 사용되는 ZnS:Cu 형광체는 저주파수에서는 녹색 발광을 하며, 고주파수에서는 청색 발광을 가진다. 본 연구는 저주파수에서도 청색을 가지는 소자를 제작하기 위하여 형광체와 염료의 혼합 비율에 따른 발광특성을 조사하였다. 염료의 혼합 비율은 0$\sim$5 wt%로 하였다. 소자의 발광현상을 고찰하기 위하여 발광 스펙트럼과 휘도를 측정하였다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2004.05a
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• pp.67-71
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• 2004

400~450nm 파장 범위의 청색광을 검출하는 Si 포토다이오드에서 $SiO_2$, $Si_{3}N_{4}$, $SiO_{2}/Si_{3}N_{4}$를 광반사 방지막으로 사용하는 경우 광반사 방지막의 두께에 따른 표면 광반사 손실을 이론적으로 계산하였다. 400~450nm 청색 파장에서 $SiO_2$, $Si_{3}N_{4}$ 단일막에 대한 최소 광반사 손실은 각각 $d(SiO_2)=700~750{\AA}$ 와 $d(Si_{3}N_{4})=500${\AA}$에서 나타났으며, $SiO_{2}/Si_{3}N_{4}$ 이중막에 대한 최소 광반사 손실은 $d(SiO_{2}/Si_{3}N_{4})=750{\AA}/(180~200){\AA}$에서 나타났다.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.133-134
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• 2006

본 논문에서는 ITO/Glass 기판에 스핀 코팅법(Spin Coating)과 열 증착법(Thermal Evaporation)을 이용하여 ITO/PEDOT:PSS/PVK/PFO-poss/Li/Al 구조를 갖는 청색 고분자 유기전계발광소자를 제작하였다. 청색 고분자 유기발광다이오드 제작시 ITO 전극을 $O_2$ gas를 이용한 Plasma Treatment와 Heat Treatment를 실시하여 기판처리가 제작된 소자의 전기, 광학적 특성에 미치는 영향에 대하여 조사하였다. Plasma와 Heat Treatment를 동시에 처리한 소자에서 가장 우수한 전기, 광학적 특성을 나타냈으며, 기판처리를 하지 않은 경우는 전기, 광학적 특성은 크게 감소하였다.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.2
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• pp.123-133
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• 2020

Four LEDs (blue, green, red, and white light) were tested to identify the most attractive wave length to utilize as the forecasting tools for the B. tabaci in glass houses. Attractiveness was evaluated by the total number of the B. tabaci attached to a yellow sticky trap. In the condition of no host plant supplement, the attraction efficacy was ordered from high to low as blue light (107.3±2.5), white light (83.0±12.1), red light (58±21.8), and green light (39.7±8.1). In the supplement of the host plant, the attraction was observed in the order of blue light (52±17.4), red light (38.7±5.8), green light (12.7±1.5), and white light (11.7±5.0). In both experimental conditions, blue light showed the highest attraction. In terms of the host plant effect to LED attraction, it varied following as white light (85.9%), green light (68.1%), blue light (51.6%), and red light (33.3%). This result suggests that red light is the least affected by the host plant. In the evaluation of the relative control efficacy, it was determined following as red light (66.7%), blue light (48.5%), green light (31.9%) and white light (14.1%) (F_3,8 = 14.7, P = 0.001). Taken together, blue light had a very high initial attraction, and red light was revealed low attraction effect by the supplement of the host plant. In field demonstration experiments, a high attractive efficacy was not observed due to low-temperature conditions, but similar higher attractive efficacy was observed in blue and red lights compared to the control. The commercialization of LEDs using red and blue in the future is expected to provide important information regarding B. tabaci population density forecast in glass house.

• Journal of Mushroom
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• v.21 no.3
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• pp.132-139
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• 2023

Light plays an important role in fruit-body development and morphology during Pleurotus spp. cultivation. To understand the effects of light color on fruit-body properties, we evaluated the fruit-body characteristics of Pleurotus spp. Varieties cultivated under blue, red, and purple LED light sources. The main results are as follows: The overall fruit-body shape showed differences depending on the color of the LED light. The fruit-bodies of mushroom cultivated under blue and purple light were generally similar to the mushroom shapes typically produced, while those of mushroom cultivated under green light were abnormally shaped, probably due to the absence of effective light source. The average cap lightness of mushrooms cultivated under blue, green, and purple LED lights was 57.0, 57.4, and 59.4, respectively. The average cap lightness of all varieties except Wonhyeong1ho and Hwang-geumsantari cultivated under the three LED light sources were statistically significantly different (P<0.05). The cap redness varied significantly depending on the LED lighting and variety. Only Gonji7hoM, the cap color mutant of Gonji7ho, showed negative cap redness values under all three LED light sources. Among the eight varieties excluding Gonji7ho, the highest cap redness was observed when cultivated under the blue LED. The average harvest weight of the varieties cultivated under purple, blue, and green LED light were 68.0, 58.3, and 50.1 g, respectively. The yield of Gonji7ho, the mushroom variety with the highest yield, cultivated under blue, green, and purple LED light were 92.8, 77.1, and 98.6 g, respectively. The earliness when grown under the purple, blue, and green LED lights were 5.3, 5.8, and 5.8 days, respectively. Among the varieties, six, three, and two cultivars showed the shortest earliness under the purple, green, and blue LED, respectively. The fruit-body lengths were 66.4, 51.8, and 46.8 mm when cultivated under green, purple, and blue lights, respectively. These results are expected to serve as a foundation for producing mushrooms with traits demanded in the market.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.388-393
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• 2015

Buckwheat sprouts are a vegetable; a functional food should provide health benefit and enhance performance as high nutritionally important substances. Buckwheat noodles are the major buckwheat food in Japan, Korea and China. In addition, Buckwheat as preventive medicine has undergone a great advancement in the last decade. Comparison of the functional properties distribution and utilization in tatary buckwheat is required of understanding the metabolites. The study was conducted to identify the sorts of phenolic compounds and metabolites in tatary buckwheat seedling at 4, 7, and 10 days seedling under the different combinations of light-emitting diode (LED) such as blue, red, mix (red, blue, and white), dark, and natural lights in stem and leaves. After breaking the dormancy, buckwheat seeds were grown in culture room under lights for 14 hrs and the dark condition for 10 hrs, at $25^{\circ}C$ for 10 days. Length of buckwheat was gradually increased under all of the conditions. Using HPLC, rutin was highest at 7 days under mix and natural light in stem and leaf, respectively. Quercetin was highest at 4 and 7 days under natural light in both. Chlorogenic acid was highest at 7 days under mix and natural in stem and leaf, respectively. Taken Together, this study indicates that phenolic compounds and metabolites present in those plants could be helpful for the human health and nutritional additive.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.427-431
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• 2002

Lateral roots of soybean sprout might reduce the quality. The study was done to measure the effect of light quality treated during 24 hour imbibition or 6 day culture on growth and development of soybean sprouts on the 6th day after culture. With the soybean seeds imbibed in 4 ppm benzyladenopurine (BA) solution for last 6 hours of the imbibition, blue and red lights were treated during the imbibition, but during 6 day culture, blue and red or far-red light treatments were done for 50 minutes or 5 hours a day, respectively, the periods taking for their cotyledons to turn green color, On the 6th day after culture, the soybean sprouts were classified by 4 categories on the base of hypocotyl length;＞7cm, 4 to 7cm, ＜4cm and non-germination, and their lateral roots, hypocotyl diameters and fraction dry weights were measured. Blue and red lights treated during the imbibition completely blocked lateral root formation regardless of the lights treated during the culture, and showed nearly the same rate of hypocotyls of longer than 4cm. The period of each light treatment forced during the culture did not influence the growth of soybean sprouts. far-red light treated for 5 hours everyday, however, had the least rate of seed germination and hypocotyls of longer than 7cm of the light quality treatments. In addition, red and far-red lights almost equally having the commercial soybean sprouts of longer than 4cm hypocotyls move elongated and selenderized than blue light and dark treatment, meaning the growth and morphology of soybean sprouts was affected by light treatments during the culture.

• Journal of Chest Surgery
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• v.31 no.10
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• pp.945-951
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• 1998

Background: Although profound hypothermia with total circulatory arrest(TCA) is a valuable maneuver in cardiac surgery, its applications have been limited due to serious complications, especially cerebral damage. In this study, the possible role of creatinine kinase-BB(CK-BB), an index enzyme of ischemic cerebral damage, was assayed as a parameter for the assessment of the cerebral complications after TCA. Hemoglobin(Hb), ionized calcium(Ca++), and blood glucose levels were also assessed as clinical parameters involved in cerebral damage. Materials and methods: Among patients with congenital heart disease, 18 patients who had been operated on with TCA were randomly selected and divided into two groups: 6 with acyanotic and 12 with cyanotic heart disease. Arterial blood from each patient was collected before and after TCA at scheduled times(15 min., 30 min, 1, 2, 4, 8, and 12hr). The levels of CK-BB, Hb, Ca++, and blood glucose were assessed in each sample. Results: As a whole, correlation between CK-BB level and blood sampling time after TCA was not statistically significant. Also, the difference in the level of CK-BB after TCA was not significant between the acyanotic and cyanotic groups. The levels of Hb and CK-BB correlated significantly. Conclusions: The results, which showed no correlation between the alterations in CK-BB level and the TCA duration, suggest that the single assay of the CK-BB level is not a representative measurement for the assessment of cerebral damage after TCA. Also, the cyanotic congenital heart disease group is not more vulnerable to cerebral damage induced by TCA.