• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.168-169
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• 2009

본 연구에서는 ITO 표면 개질에 의한 유기 발광 소자의 특성 변화에 대해서 연구하였다. ITO 전극은 발광 소자의 투명 전극으로 널리 사용되고 있으며 이러한 발광 소자의 특성은 ITO의 표면 상태에 따라 민감하게 반응한다. ITO 표면 개질은 ITO와 유기물 사이의 쇼트기 장벽을 감소시키며, 전극과 유기물의 점착을 향상시켜 준다. 본 실험에서는 습식 처리 방식으로 self-assembled monolayer(SAM)을 사용하였다. 유기 발광 소자의 특성은 SAM 처리에 의해 향상 되었다. 유기 발광 소자는 ITO/SAM/TPD(50nm)/$Alq_3$(70nm)/LiF(0.5nm)/Al(100nm)의 구조로 제작하였으며, ITO의 표면 특성은 일반적인 특성 기술에 의해 연구되었다. SAM 처리된 소자는 SAM 처리하지 않은 소자에 비해 구동 전압, 발광 세기, 외부 양자 효율 등이 향상되었다. ITO의 SAM 처리 시간을 0/10/15/20/25분으로 하여 소자를 제작하였다. 15분간 SAM 처리한 소자는 SAM 처리하지 않은 소자에 비해 외부 양자 효율과 전류 효율이 2.6배 상승하였다. 본 실험을 통하여 ITO 표면 위에 SAM층을 삽입한 걸과, 구동 전압, 발광 세기, 효율 등이 향상됨을 알 수 있었다.

• Journal of the Korean Chemical Society
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• v.41 no.10
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• pp.524-534
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• 1997

Analysis of additives in cured rubber is often a difficult task for analytical chemists because of a wide variety of complex components. Conventional analyses of additives and rubbers have been done in multistep, off-line processes with large sample size and extensive sample preparations. The coumarone-indene resin, resorcinol-formaldehyde resin, and prevulcanization inhibitor have been characterized by their pyrolysis pathways and mass spectra of characteristic pyrolyzates. Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) was used in the identification of additives without any sample pretreatment. This result shows that several organic additives in cured rubber can be directly analyzed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.3
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• pp.547-554
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• 2008

In this paper, two-stage pipelined floating-point multiplier (FP-MUL) is designed. The FP-MUL processor supports single precision multiplication for 3D graphic APIs, such as OpenGL and Direct3D and has area-efficient and low-latency architecture via saturated arithmetic, area-efficient sticky-bit generator, and flagged prefix adder. The FP-MUL has about 4-ns delay time under $0.13{\mu}m$ CMOS standard cell library and consists of about 7,500 gates. Because its maximum performance is about 250 MFLOPS, it can be applicable to mobile 3D graphics application.

• Korean Journal of Poultry Science
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• v.29 no.1
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• pp.45-52
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• 2002

Cryoprotective effects on chicken surimi during storage were investigated. Chicken surimi from mechanically deboned spent layer meat was prepared with 4 volumes of 0.5% NaCl washing, and then blended with or without cryoprotectants (8% trehalose, 8% oligosaccharide) prior to frozen storage at $-18^{\circ}C$ to 10 weeks Redness (a) of all surimi decreased during storage. Color stability increased during storage when lightness increased but redness decreased. At this Point, surimi maintained a better color quality as followed order; trehalose > oligosaccharide ) non-additive. Gel strength such as compressive force, hardness, adhesiveness and gumminess tended to decrease during frozen storage. Cryoprotectants provided significantly better textural properties than non-auditive. Surimi with trehalose showed the highest adhesiveness. In conclusion, trehalose and oligosaccharide seemed to be good cryoprotectants of chicken surimi. Especially, trehalose resulted in better cryoprotectant than oligosaccharide because of better color stability, better textural properties, and lower sweet characteristics.

• Journal of the Korean GEO-environmental Society
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• v.14 no.10
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• pp.39-47
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• 2013

Recently, there have been various domestic construction activities related to the reclamation of the dredged soils to expand the land use. However, the reclaimed grounds made of the dredged soils cause various problems due to highly compressible and low shear strength nature. Particularly, this nature induces huge problems in case of the harbor facilities and road construction on the reclaimed sites. Furthermore, in the reclamation activities, the marine dredged soils are often used instead of the well sorted sand, which induces problems of compressibilities. Therefore, in this study, the mechanical characteristics of artificial soil mixture of kaolinite representing the marine dredged soils and the pond ash. A large consolidometer is designed and manufactured to produce the artificial soil mixture. To represent various mixing ratio between the fly ash and bottom ash in the pond ash, six samples with the same stress history are made with different mixing ratio among kaolinite, bottom ash and fly ash. Isotropically consolidated and undrained compression tests are performed to investigate the shear characteristics of soil mixtures. Based on the experimental results, as the components of mixed ash increase, the friction angle increase and the cohesion values decrease. Also, the porepressure parameters at failure, Af increase with the mixing components of the pond ash. The portion of bottom ash has more impact on the shear behavior than that of fly ash.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.64-64
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• 2003

대구 인공종묘 생산 기술 개발의 일환으로 수정란에 기생하여 폐사를 유발하는 세균 및 세균 감염 경로를 파악함으로써 수정란의 생존율과 부화율 향상을 위하여 본 실험을 실시하였다. 세균 감염 경로를 파악하기 위하여 난소와 정소 자체 세균 감염 여부를 조사하였다. 일반배지 (BHIA)와 비브리오 선택배지 (TCBS)를 사용하여 세균검사를 실시하였다. 난소의 세균 검사는 생식소 내부를 일부 절개한 후 멸균 roop를 찔러 세균을 검사하였고, 정소는 채정하기 전 복부를 절개하여 멸균 roop로서 적출하여 배지에 도말한 후 배양하였다. 수정란 내 세균 수는 수정란을 각각 20개씩 샘플하여 난 외부에 기생하는 세균을 제거하기 위하여 난소독제로 이용되고 있는 benzalkonium 0.1%로 1분간 소독한 후 멸균 생리식염수로 3회 세척하여 호모게나이즈하여 검사하였다. 호모게나이즈한 액 중 100${\mu}\ell$를 pipetting하여 일반배지(BHIA)에 도말하여 인큐베이터에서 배양하였다. 난소와 정소 내에서 세균이 검출됨에 따라 수정 시 세균 감염을 억제하기 위하여 자외선 살균해수와 일반해수를 수정액으로 사용하여 발생율을 비교 시험하였다. 수정 시간은 1분으로 동일하게 적용하였으며, 수정 용기는 멸균 처리된 일회용 100$m\ell$ 플라스틱 용기를 사용하였다. 수정 후 과다한 정자를 제거하기 위한 세란은 1$\ell$ 멸균 비이커에서 5회 30분 가량 실시하여 정자를 제거하였고 멸균 봉으로 저어주면서 수정란의 점착력을 제거하였다. 수정란은 100$\mu\textrm{m}$ 그물망으로 수정란 유실을 방지한 플라스틱 용기에 수용하여 유효수량 270$\ell$ FRP 수조에 수용하여 3$\ell$/min 환수하였고, 수온은 자연수온 1$^{\circ}C$로 유지하였다. 발생율은 만능투영기로 3회 측정하였다. 수정 후 세균과 기생충에 의한 수정란의 폐사를 억제하기 위하여 수정 직후, 수정 후 1일, 2일째 oxytetracycline과 iodine 처리에 따른 발생율 변화를 조사하였다. 발생율은 만능투영기로 조사하였고, 시험구별로 3회 측정하였다. 경과 일수별로 약제 처리는 약제 미처리 수정란 중 정상적인 발생이 이루어지고 있는 것을 선별하여 조사하였다. 약제 처리에 따른 배체 발생 단계는 수정 후 1일째는 상실기, 2일째는 포배기였다. 수정란 및 대구 자어에서 분리된 V. splendidus 에 의한 폐사를 예방하기 위해 in vivo에서 oxytetracycline 외 5종의 항생제를 대상으로 96well plate에서 최고 농도 250ppm부터 2 fold로 단계 희석하여 $25^{\circ}C$에서 48시간 배양하여 MIC를 조사하였다. 세균 감염경로 파악을 위하여 난소, 정소 및 정자에서 세균을 분리한 결과 일반배지 및 비브리오 선택배지에서 모두 균이 검출되었고, 균 동정 결과 터봇 자어에서 검출된 것으로 보고된(Gatesoupe et al., 1999) V. splendidus로 나타났다. 수정액과 정자 및 미수정란의 세균 분리 결과 일반배지에서 3$\times$10/ml ~ 7$\times$10/ml로 균이 검출되었다. 수정액을 일반해수와 자외선 살균 해수를 사용하여 발생율을 비교한 결과 수정 후 3일째 발생율은 자외선 살균해수 72.3%, 일반해수 52.7%였으며, 수정 후 7일째 40.9%와 25.1%로 자외선 살균해수가 유의적으로 높게 나타났다. 수정 후 경과 일수별로 oxytetracycline과 Iodine을 처리한 결과 수정 직후 처리한 시험구는 7일째 19.8%와 18.9%로 대조구 23.1%와 유의적인 차이가 없는 것으로 나타났다. 수정 후 1일째 처리한 시험구는 54.5%와 56.8%, 수정후 2일째 처리구는 47.9%와 50.6%로 두 시험구 모두 대조구와 수정 직후 처리구보다 유의적으로 높게 나타났다. 수정란 및 대구 자어에서 분리된 V. splendidus 에 의한 폐사를 예방하기 위해 in vivo에서 항생제 종류별 MIC 조사 결과 oxytetracycline이 0.48ppm으로 가장 효과가 높은 것으로 나타났다.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.489-500
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• 2018

Rural Development Administration (RDA) is promoting the AFACI IPM (Asian Food & Agricultural Cooperation Initiative program). AFACI consist of 12 countries including Bangladesh, Cambodia, Thailand, Vietnam and so on. The main goal of the AFACI IPM project is 'Establishment of an international cooperative network for the best management of migratory rice planthoppers and setting data-base of pests occurrence information. As a result of the suvey, Planthoppers were increasing all the way from tillering stage to ripe stage and do not appear to be peak of one or two like korea case. In detail, 1,673 of BPH (Nilaparvata lugens) occurred in survey site of Svay Reang, Cambodia, followed by 1.237 at Dobila, Bangladesh. In the case of White backed planthopper (Sogatella furcifera), 1,163 of WBPH occurred in survey site of Dobila, Bangladesh and 849 WBPH were collected at Hamkuria, Bangladesh. It is expected to verify the occurrence and movement patterns of hoppers among member countries in the future.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.120-126
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• 2012

Two experiments were designed and executed to measure the effectiveness of the two-fluid fogging system in controlling whiteflies in tomato cultivation. The two-fluid fogging system that lowers temperature and raises humidity in greenhouses provides an eco-friendly method of preventing damages from whiteflies. The first experiment elucidated the effect of fogging treatment on the elimination of whiteflies and investigated the sectional distribution of whiteflies. The second experiment analyzed the vertical distribution, the motility of whiteflies and reduction of the number of whiteflies under the fogging system. The result of the experiments showed that the fogging system lowered the number of whiteflies and decreased their motility significantly. It affected the vertical distribution of whiteflies as well. Based on these experiments, we strongly recommend using the fogging system to prevent and control whiteflies in greenhouses, in addition to installing yellow sticky traps in the areas that have the highest density of whiteflies.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.947-954
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• 1992

Polyethylene glycol (PEG) grafted poly (γ-benzyl L-glutamate) (PBLG) was synthesized by the substitution reaction of PBLG and PEG having primary amino groups at both ends. PEG-g-PBLG films containing hydroxyl group were also prepared by the substitution reaction of PEG-g-PBLG film and ethanolamine (EA). Adhesion of platelets and activation of plasma proteins on the copolypeptide films were studied. The results showed that platelets are less adhered and activated on the PEG-g-PBLG than on other polypeptides and plasma recalcification time (PRT) on the PEG-g-PBLG was longer than that on other polypeptides. These results were consistent with those of blood clotting time and thrombus formation on the polypeptides. As a results, PEG-g-PBLG surfaces showed better blood compatibility than PBLG or PEG-g-PBLG-EA surfaces.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.256-264
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• 2018

The purpose of this study was to investigate the relationship between oral health behaviors and the results of the oral dysentery test for dental hygienists and students at Gyeonggi - do and Chungcheongnam - do. Self - filling questionnaires and oral diseases. The following conclusions were obtained. The most common toothbrushing frequency was three times a day (60.2%), and the most dominant frequency of eating between meals was once or less(49.7%). The most common snack that they had was stickiness-free sweetened food(66.5%), and the type of beverage that they had the most was sweetened beverages(49.7%). The average stimulated saliva flow rate was 9.41ml, and they got a mean of 9.52 in the buffering capacity of saliva. The average glucose clearance time was a mean of 12.02. When they took a streptococcus mutans colony count test, 80.1 percent belonged to the low-risk group(<$10^5$), and 82.6 percent belonged to the low-risk group(<$10^5$) when a lactobacillus test was conducted. There was a positive correlation between the irritant saliva fraction and the non-irritating saliva and saliva buffering ability. In the fluoride application experience, the glucose retention time was 10.66 minutes and the fluoride application experience was 13.33 minutes. (P = .008). The importance of oral health, which is directly linked to general health, should be emphasized in order to improve the quality of life as well as the life expectancy. For oral health, which is directly linked to systemic health, it is necessary to provide opportunities for oral health education that can be easily accessed by the public, and to continuously develop and provide oral health care programs for a lifetime.