• 농업생명과학연구
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• 제43권5호
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• pp.73-82
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• 2009

한국의 농업분야에는 여러 가지 인증제도가 존재한다. 그 예로 유기농산물 인증, GAP인증, KPGI인증, TOP푸르트/TOP라이스 인증 등이 있다. 이러한 인증제도는 소비자에게 안전하고 고품질의 농산물을 보장하기 위해 시행되었다. 하지만 각 인증제도가 명확한 목적을 보유함에도 불구하고 이러한 인증제도들이 소비자에게 관련정보를 수반하는데 성공적이지 못하다는 평가를 받고 있다. 그 이유로는 현존하는 몇몇의 인증제도가 오히려 소비자들을 혼란스럽게 하고 있다는 것이다. 그리고 각각의 인증제도를 별도로 유지하고 홍보하는 것은 더 많은 비용을 발생시킨다. 이 연구에서는 여러 인증제도를 활용하여 이러한 문제를 해결하고자 하는데 그 목적을 두고 있다.

• 한국기후변화학회지
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• 제8권1호
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• pp.63-71
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• 2017

It is recognized that tetrafluoromethane ($CF_4$) has a great influence on global warming. The $CF_4$ is known to have a large impact on climate change due to its large global warming index. In this study, a waterjet plasma scrubber (WPS) was designed and manufactured for the $CF_4$ decomposition. The WPS is a novel technology which is combined a gliding arc plasma and water injection at the center of the plasma discharge. This can give an innovative way for $CF_4$ decomposition by achieving larger plasma columnand generating OH radicals. A performance analysis was achieved for the design factors such as waterjet flow rate, total gas flow rate, consumption electric power, and electrode gap. The highest $CF_4$ decomposition and energy efficiencies were 64.8% and 6.43 g/kWh, respectively; Optimal operating conditions were 20 mL/min of waterjet flow rate, 200 L/min total gas flow rate, 5.3 kW consumption electric power, and 4.4 mm electrode gap. As for the 2 stage reactor of the WPS, the $CF_4$ decomposition efficiency improved as the 85.3% while the energy efficiency decreased as the 5.57 g/kWh.

• 대한전자공학회논문지TC
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• 제39권9호
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• pp.35-43
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• 2002

본 논문에서는 협소한 갭이 있는 마이크로스트립 링의 특성을 분석하였으며, 이를 주파수가변(tunable) 마이크로파 밴드갭(Microwave bandgap：MBG) 구조로 제안하였다. 마이크로파 밴드갭(MBG)의 중심주파수는 링의 반지름에 의해 결정되었으며 링 공진기의 홀수 모드에 해당하는 주파수영역에서만 저지대역이 존재하였다. 제안된 마이크로스트립 MBG 링에서 저지대역은 링에 있는 협소한 갭에서 전자기파의 반사로 인해 형성되며 갭 사이에 부착한 리액티브 성분의 값을 변화시킴으로써 저지대역이 형성되는 영역을 결정 할 수 있다. 갭 사이에 부착한 캐패시터는 저지대역의 중심주파수를 낮은 주파수영역으로 이동시켰고 인덕터는 저지대역의 중심주파수를 높은 주파수영역으로 이동시키는 결과를 보였다. 이렇게 갭 사이에 배랙터(varactor)를 부착한 마이크로스트립 MBG 링은 마이크로파 스위치로 유용하게 사용 할 수 있을 것이다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.857-860
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• 2004

Cubic CdS thin film with the strongest XRD peak (111) at diffraction angle $(\theta)$ of 26.5 was well made at substrate temperature of $150^{\circ}C$. At that time, lattice constant a of the thin film was $5.79{\AA}$, grain size of that was more over ${\mu}m$ and it's resistivity was over $10^3{\Omega}cm$. And the peak of diffraction intensityat miller index (111) of CdS:In thin film with dopant In of 1 atom% was shown higher about 20 % than undoped CdS thin film. Also, CdS:In thin film had in part hexagonal structure among cubic structure as secondary phase. Lattice constant of a and grain size of secondary phase of the film with dopant In of 1 atom% was $5.81{\AA}$ and around $1{\mu}m$ respectively The lowest resistivity of $5.1{\times}10^{-3}{\Omega}cm$ was appeared on dopant In of 1.5 atom%. Optical band gap of undoped CdS thin film was 2.43 eV and CdS:In thin film with dopant In of 0.5 atom% had the largest band gap 2.49 eV.

• 컴퓨터교육학회논문지
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• 제15권6호
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• pp.43-52
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• 2012

학습자의 정보활용능력은 학습자의 창의성을 신장시키는 자기주도학습을 가능하게 한다. 그러나 중등학교에서 정보소양 및 정보활용교육은 2009년 개정 교육과정이 시행되면 없어 질 것으로 예상된다. 따라서 중등학교에서 학습자의 정보활용능력 계발은 교사의 교과 수업을 통해 이루어질 수밖에 없을 것이며, 교사의 정보활용능력은 매우 중요한 능력으로 간주되어야 한다. 본 연구에서는 현직교원과 예비교사의 정보활용능력 실태를 조사하고 이들간 정보활용능력 격차를 분석하였다. 연구 결과, 현직교원과 예비교사의 종합 정보활용능력 지수는 각각 74.4점과 50.5점으로 나타났다. 예비교사의 정보활용능력은 현직교원의 약 68% 수준인 것으로 분석되었다. 따라서 시 도교육청 및 교원양성기관은 예비교사의 정보활용능력 향상을 위한 방안을 수립 운영하여야 할 것이다.

• 동아시아식생활학회지
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• 제24권3호
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• pp.359-367
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• 2014

This study analyzed phytochemicals, including various carotenoids, tocopherol and L-ascorbic acid, in green, yellow and orange paprikas (GP, YP and OP) and measured the preventive effects of lipophilic extracts from different colored paprikas on the blockage of gap junctional intercellular communication (GJIC), which is known as a cellular event associated with tumor promotion. Main carotenoids were lutein and ${\beta}$-carotene in GP, lutein, ${\beta}$-carotene, capsanthin, violaxanthin, ${\beta}$-carotene and capsorubin in YP, and lutein, ${\beta}$-carotene, cryptoxanthin and zeaxanthin in OP. Total carotenoid contents were $65.54{\pm}15.87$ mg/100 g dw in OP, $11.98{\pm}0.69$ mg/100 g dw in YP and $10.30{\pm}1.43$ mg/100 g dw in GP. Tocopherol contents were highest in GP compared with in YP and OP, whereas L-ascorbic acid contents were very high in all paprikas. We determined the non-cytotoxic levels of paprika extracts by MTT assay, which showed less formation of reactive oxygen species (ROS) induced by $500{\mu}M$ $H_2O_2$ for 1h. Finally, we showed that pretreatment of paprika extracts prevented inhibition of GJIC induced by $500{\mu}M$ $H_2O_2$ by the scrape-loading/dye-transfer technique. In conclusion, each colored paprika has unique phytochemicals and showed a protective effect on inhibition of GJIC.

• 대한치과기공학회지
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• 제42권3호
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• pp.234-239
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• 2020

Purpose: We investigated the marginal fit between abutment and metal copings according to impression technique, wax block types, and metal types. Methods: We selected the traditional impression method of using rubber impression materials and the digital impression method of using oral scanners, three types of wax blocks, and two types of metal, both of which were domestically and commercially available, were selected to produce metal copings, and the marginal fit was determined through the use of silicon replication. Results: The measurements of axial wall fit revealed that the IYV specimens had the best fit, with a mean gap of 24.11±5.95 ㎛, followed by CEV, CHV, CSS, CSV, CES, CHS, and IYS specimens (mean: 33.44±8.41 ㎛). The differences were not statistically significant. The marginal gap measurements showed that the CEV specimen had the smallest gap, 17.25±4.13 ㎛, followed by the CSV, CHV, CSS, CES, CHS, IYV, and IYS specimen (mean: 43.47±15.63 ㎛). The differences were statistically significant. Conclusion: The axial wall fit of the metal coping (VeraBond2V; Aalba Dent, Inc., Fairfield, CA, USA) produced by the lost wax technique with the traditional impression method was excellent. The marginal fit of the metal coping (VeraBond 2V) produced by wax milling with the use of an oral scanner was also excellent. The marginal fit of the metal coping was within the clinically acceptable limits in all groups.

• 대한지역사회영양학회지
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• 제14권1호
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• pp.43-54
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• 2009

The purpose of the study was to investigate the status of the nutritional education program on educational perception, facilities, contents and systems, which were focused on the school obesity education in the elementary school. A five point Likert scale was used to evaluate the importance and performance of each item in four sections of the survey and Importance-Performance Analysis (IPA; gap between importance and performance) matrix analysis was applied to determine improvement priority. The findings from IPA matrix analysis are in the following. The items of the sections to be improved intensively are recognition of parents and in-charge teacher, availability of the education place, preparation of consulting room, preparation of various teaching media, interest of an education program, meal adjustment of overweight children, combination with education and exercise, education for psychological factors, development of scientific and systematic education program and reduction of meal service duty for education. Accordingly, the IPA matrix analysis suggested that an intensive improvement area should be excessively concentrated on for better performance. The regional gap between importance and performance showed significant difference for textbook and diet of overweight children in Kyunggi-Do. There were significant differences for the government perception, dietary habits and food-life education, fast-food education, education for breakfast importance, and education of school meal indication system and method to read food nutrition indication in Chollabuk-Do. As for the age gap between importance and performance, the twenties showed significantly bigger gaps in perception of school dietitians and linking between school meals and diet education. Therefore, more proactive efforts for the education for obesity prevention are necessary to prevent childhood obesity in elementary school and to help children to possess better health throughout their entire lives.

• Food Science and Biotechnology
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• 제18권3호
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• pp.630-635
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• 2009

This study was performed to analyze various antioxidants, to evaluate the antioxidative activities, and to measure the protective effect for gap junction intercellular communication (GJIC) to assess the functional potency of the cherry tomato. The ascorbic acid, lycopene, and ${\beta}-carotene$ were measured at $503.4{\pm}9.6$, $39.7{\pm}1.5$, and $7.4{\pm}0.3$ mg/100 g d.w., and ${\alpha}-$, ${\beta}+{\gamma}-$, ${\delta}-tocopherol$ contents were measured at $8.3{\pm}0.1$, $1.7{\pm}0.0$, and $0.1{\pm}0.0$ mg/100 g d.w., respectively. Cherry tomato extract using hexane/acetone/EtOH (2:1:1, CTE) exhibited a ABTS radical scavenging activity with an $IC_{50}$ value of $48.83{\pm}0.30\;{\mu}g/mL$. The cherry tomato protected against the inhibition of GJIC induced by $H_2O_2$ in WB-F344 rat liver epithelial cells, and the reduction in phosphorylated Cx43 was most clearly correlated with the concentration of CTE. These results demonstrated that the cherry tomato harbors a wealth of potent antioxidants and might be protect human body against the inhibition of the GJIC by toxic components.

• Advances in materials Research
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• 제2권2호
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• pp.77-91
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• 2013

High quality nanoparticles of neodymium barium niobium ($NdBa_2NbO_6$) perovskites have been synthesized using an auto ignition combustion technique for the first time. The nanoparticles thus obtained have been characterized by powder X-ray diffraction, thermo gravimetric analysis, differential thermal analysis, Fourier transform infrared spectroscopy, Raman spectroscopy and transmission electron microscopy. UV-Visible absorption and photoluminescence spectra of the samples are also recorded. The structural analysis shows that the nano powder is phase pure with the average particle size of 35 nm. The band gap determined for $NdBa_2NbO_6$ is 3.9 eV which corresponds to UV-radiation for optical inter band transition with a wavelength of 370nm. The nanopowder could be sintered to 96% of the theoretical density at $1325^{\circ}C$ for 2h. The ultrafine cuboidal nature of nanopowders with fewer degree of agglomeration improved the sinterability for compactness at relatively lower temperature and time. During the sintering process the wide band gap semiconducting behavior diminishes and the material turns to a high permittivity dielectric. The microstructure of the sintered surface was examined using scanning electron microscopy. The striking value of dielectric constant ${\varepsilon}_r=43$, loss factor tan ${\delta}=1.97{\times}10^{-4}$ and the observed band gap value make it suitable for many dielectric devices.