• Electronics and Telecommunications Trends
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• v.19 no.4 s.88
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• pp.26-34
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• 2004

국내 디지털방송 서비스는 2001년 디지털 본 방송을 시작으로 디지털방송 서비스와 관련 장비나 수신 단말 장치 등이 점차적으로 성능이나 기능면에 있어 많은 발전이 이루어지고 있다. 또한 디지털방송 분야에서 보다 다양한 서비스를 사용자에게 제공하기 위해 비디오/오디오 방송과 함께 각종 멀티미디어 데이터를 함께 실어 보내는 디지털 데이터방송 기술에 대한 관심이 집중되고 있는 실정이다. 이러한 디지털데이터방송 서비스를 위해 북미, 유럽, 일본 등지에서는 관련 표준을 만들어 사용하고 있거나 사용을 고려 중에 있다. 현재 국내에서도 2001년도에 지상파 데이터방송 서비스를 위해 북미 ATSC에서 승인한 데이터방송 표준인 DASE를 잠정 표준으로만 채택한 상황이다. 그러므로 국내 데이터방송 서비스의 활성화를 위해서는 우선 국내 표준이 확정되어야 할 것이며 이에 비추어 본 고에는 현재까지 진행되고 있는 국제 표준화 기구들간의 데이터방송 기술 및 표준화 동향을 살펴보고 이와 관련된 국내 데이터방송 표준화 동향을 설명하고자 한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2002.11a
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• pp.237-242
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• 2002

DASE(DTV Application Software Environment)는 ATSC의 지상파 방송 표준으로 한국에서는 월드컵과 아시안게임을 거쳐 현재까지 시험방송 중에 있다. 국내에서는 주요한 데이터전송 방식으로 데이터 carousel 프로토콜을 사용하고 있는데, 지금까지는 전송되는 파일의 이름과 content type에 관한 정보가 DST(Data Service Table)에 들어가 있었으나, ATSC 표준이 변경됨에 따라 이 정보가 DII(Download Info Indication)[2]의 descriotor로 위치가 변경되었다. 이로 인해 DII에 삽입해야 하는 데이터의 양이 증가하여 하나의 DII에 삽입 가능한 모듈의 개수가 감소되었고 전송량이 증가하게 되었는데, 본 논문은 base URI와 default content type을 통해 이러한 제약을 완화할 수 있는 방식에 대해 ATSC S13에 제안한 내용을 토대로 기술하였다.

• Journal of Korean Vacuum Science & Technology
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• v.2 no.2
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• pp.118-121
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• 1998

Diisopropylselenide (DIPSe) is employed for the metalorganic vapor phase epitaxy (MOVPE) of ZnSe in order to eliminate premature gas phase reaction while maintaining negligible carbon incorporation and preserving relatively low growth temperature. In combination with dimethylzinc, single crystalline ZnSe layers were grown on GaAs at temperature around 450$^{\circ}C$. Secondary ion mass spectrometry showed a negligible carbon incorporation in ZnSe films grown from DIPSe even at high [Ⅵ]/[II] ratios, in contrast of a carbon concentration of 1021 cm-3 in ZnSe films grown from diallyselenide (DASe). Crystalline and interface quality are demonstrated by secondary electron microscopy, secondary ion mass spectroscopy and double crystal X-ray diffraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.224-228
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• 1990

Cabbage contained high peroxidase activity among tested plant sources. The cabbage peroxi-dase can replace horseradish peroxidase to assay glucose with glucose oxidase. The amount of glucose can be determined quantitatively by glucose oxidase-cabbage peroxidase. The opti-mum pH and temperature for enzymatic glucose determination by glucose oxidase-cabbage peroxidase were 6.0 and 35-45$^{\circ}C$ respectively. The glucose assay was inhibited by addition of various metal salts such as mercuric chloride lead acetate silver nitrate ammonium molyb-date sodium tunstate and cupric sulfate. The relationship between absorbance and amount of glucose was linear up to 8.33 mM glucose in the assay mixture under the assay conditions.

• KSBB Journal
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• v.11 no.2
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• pp.151-158
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• 1996

For the effective ethanol fermentation, the high concentration of sugar as the substrate of microbial fermentation is required. The most important reason in the inefficient hydrolysis; the easy deactivation of enzyme by temperature or shear stress and the severe inhibition effects of its products. In our work, we comprehended the kinetic characteristics of cellulose and ${\beta}$-glucosidase in the progress of hydrolysis, and observed the potential inhibitory effects of the hydrolyzed products and the deactivation of enzymes. We also tried to present the kinetic model of enzymatic hydrolysis of cellulose, which is applicable to process at the high concentration of sugar. Cellulase and ,${\beta}$-glucosidase exhibit diverse kinetic behaviors. At a level of only 5g/$\ell$ of glucose, the ${\beta}$-glucosidase activity was reduced by more than 70%. This result means that ${\beta}$-glucosldase was the most severely inhibited by glucose. Also at l0g/$\ell$ of cellobiose, the cellulose lost approximately 70% of its activity. ${\beta}$-glucosldase was more sensitive to deactivation than cellulose by about 1.6 times. The comprehensive kinetic model in the range of confidence was obtained and the agreement between the model prediction and the experimental data was reasonably good, testifying to the validity of the model equations used and the associated parameters.

• Journal of the Korean Wood Science and Technology
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• v.35 no.5
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• pp.100-108
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• 2007

$\beta$-Glucosidase from Laetiporus sulphureus among the enzymes related to lignocellulosic biomass degradation to sugars for using alternative bioethanol production was characterized. The highest activity of $\beta$-glucosidase was obtained on cellobiose at shaking culture. For the characterization and purification of $\beta$-glucosidase culture solution was concentrated and then purified by FPLC using ion exchange and size exclusion column. According to the results of SDS-PAGE, native PAGE and microfluidic system of purified enzyme, protein band was observed at about 132 kDa. Optimal pH and temperature of purified $\beta$-glucosi-dase were 5.0 and $60^{\circ}C$, respectively. In the kinetic properties of $\beta$-glucosidase on various substrates such as sophorose, gentiobiose and cellobiose, $K_m$ was 0.81, 1.07 and 1.70 mM, respectively.

• Journal of Life Science
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• v.11 no.6
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• pp.503-508
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• 2001

The essential oil of Acorus gramineus(Aracease), which has been used as an antioconvulsant in Korean folk medicine, was evaluated for its effects on antioxidative system in vitro and in vivo. This mixture of terpenes showed inhibitory effects on xanthine oxidase activity with 13.3% at 10 $\mu\textrm{g}$/ml and on aldehyde oxidase activity with 5.0% at 1$\mu\textrm{g}$/ml. Lipid perosidation was inhibited by 49.4% at 1.0 mg/ml of the essential oil in vitro and by 16.7% after 7 days inhablation of an oil as compared to PTZ-treated control group. DPPH radical scavenging activity of this essential oil was ralatively werak.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.3
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• pp.215-221
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• 1995

This study was undertaken to investigate the effect of Taraxacum herba extract on the hepatic xanthine oxidase activity as a oxygen free radical generating enzyme in vitro and in vivo. It was observed that partial purified hepatic xanthine oxidase (type O) activity was strongly inhibited by the addition of Taraxacum herba n-butanol extract in vitro. The Km value of xanthine oxidase without affecting the Vmax value for xanthine was significantly increased by the addition of ta-dase (type O) activity was significantly inhibited by the treatment of Taraxacum gerba n-butanol ex-tract for 5days(over 40mg/kg, i.p), whereas, xanthine oxidase (type D) activity was not changed by the injection of Taracacum herba n-butanol extract. Meanwhile, liver weight / body weight(%), serum alanine aminotransferase activity and hepatic lipid peroxide content in Taraxacum herba n-buta-nol extract-treated rat were not changed. These findings led us to conclude that Taraxacum herba n-butanol extract may regulate the hepatic xanthine oxidase type O activity to prevent toxic effect of oxidative stress by the oxygen free radicals.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.265-274
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• 2014

Physiological characteristics of two Korean golden kiwifruit cultivars, 'Halla Gold' and 'Haehyang', were compared to determine the storage potential of fruit. The soluble solid levels of the fruit were 8.9 and 6.9 oBrix in 'Halla Gold' and 'Haehyang' at harvest, respectively but increased up to 15.4 in 'Halla Gold' and 17.5 oBrix in 'Haehyang' after 2 months of storage. Major sugars were fructose and glucose, and sucrose content was relatively low regardless of cultivar. The edible quality of 'Haehyang' was better than 'Halla Gold' because of higher amount of sugars. Firmness of the fruits gradually decreased as the increase of storage period in 'Halla Gold' in both flesh and core tissue. Th firmness loss of 'Haehyang' fruit was faster in the first 2 months and then became slow. After 75 days of storage, the firmness of 'Haehyang' fruit was only 5.2% at harvest. Core tissue was soften enough to eat at ripe stage. Wall modifying enzyme activities including xylanase, ${\alpha}$-L-arabinofuranosi-dase and ${\beta}$-galactosidase were consistently higher in 'Haehyang' and the activity of pectate lyase was more increased than 'Halla Gold' after 2 months of storage. Respiration rate of 'Haehyang' was higher than 'Halla Gold' and further increased after 2 months of storage. Weight loss was much higher in 'Haehyang' which showed higher rate of the firmness loss. The storage potential of golden kiwifruit was estimated to be about 2 months for 'Haehyang' and 3 months for 'Halla Gold' when determined on the basis of the fruit firmness.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.616-623
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• 2017

The purpose of this study is to examine satisfaction with liberal education at H university. In particular, the study is interested in students' and satisfaction with the courses of and , compulsory liberal studies. As a result of analysis, students were most satisfied with 'the percentage of liberal studies credits', being followed by 'the number of students per liberal studies class' and 'the systemicity of curriculum.' The survey also showed that, in and , students were highly satisfied with 'chance for communication with native faculty, improvement of ral expression skills' and 'improvement of orthography and grammar skill and so on. With regard to items whose satisfaction were low, the survey showed that there was the lack of connectivity between liberal studies and employment in 3 categories in common. Therefore, a direction toward enhancement of efficiency in connection with career center and the like was required in addition to establishing, developing and specifying employment category in liberal studies.