• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1346-1355
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• 2012

This study was carried out to investigate the characteristics of black jujube and Zizyphus jujube extracts during lactic acid fermentation. Both extracts were fermented using Lactobacillus fermentum YL-3. As a result, viable cell number rapidly increased until 24 hours, after which it gradually decreased. Before lactic acid fermentation, the $IC_{50}$ of black jujube, which was 0.014 mg/mL, was lower than that of Zizyphus jujube. Further, black jujube showed stronger antioxidant activity (374.21 mg AA eq/g) than Zizyphus jujube. Contents of total polyphenolics in both extracts were 15.46 mg/g and 13.61 mg/g, respectively, whereas contents of total flavonoids were 374.21 ${\mu}g/g$ and 64.25 ${\mu}g/g$. After lactic acid fermentation, there was no significant increase in DPPH or ABTS free radical scavenging activity. Total polyphenolic content of Zizyphus jujube decreased to 12.39 mg/g upon fermentation, whereas flavonoid content significantly increased to 291.58 ${\mu}g/g$. Further, polyphenolic and flavonoid contents of black jujube increased from 15.46 mg/g to 17.46 mg/g and from 374.21 ${\mu}g/g$ to 1,135.29 ${\mu}g/g$, respectively. These results demonstrate that 9-Times Steamed and Dried increased functional components. Especially, lactic acid fermented black jujube showed remarkably high antioxidant activity. These results confirm the potential use of lactic acid fermented black jujube as a valuable resource for the development of functional foods.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.227-234
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• 2010

The vertical response spectra using the observed ground motions from the recent more than 30 macro earthquakes were analysed and then were compared both to the seismic design response spectra (Reg Guide 1.60), applied to the domestic nuclear power plants, and to the Korean Standard Design Response Spectrum for general structures and buildings (1997). 176 vertical ground motions, without considering soil types, were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that response spectrum had strong dependency on epicentral distance. The results also showed that the vertical response spectra revealed much higher values for frequency bands above 5~7 Hz than Reg. Guide (1.60). The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the vertical response spectra revealed much higher values for the frequency bands below 0.2 second (5 Hz) than the Korean Standard Response Spectrum (SD soil condition). These frequency-dependent spectral values could be related to the characteristics of the domestic crustal attenuation and the effect of each site amplification. However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of vertical seismic design response spectrum should be considered more significantly for the frequency bands above 5 Hz.

• Tunnel and Underground Space
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• v.20 no.6
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• pp.399-407
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• 2010

The horizontal response spectra using the observed ground motions from the recent more than 19 macro earthquakes were analysed and then were compared to both the seismic design response spectra (Reg Guide 1.60), applied to the domestic nuclear power plants, and the Korean Standard Design Response Spectrum for general structures and buildings (1997). 130 horizontal ground motions, without considering soil types, were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that response spectrum have strong dependency on epicentral distance. The results also showed that the horizontal response spectra revealed much higher values for frequency bands above 5 Hz than Reg. Guide (1.60). The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the vertical response spectra revealed much higher values for the frequency bands below 0.3 second than the Korean Standard Response Spectrum (SD soil condition). These spectral values dependent on frequency could be related to characteristics of the domestic crustal attenuation and the effect of each site amplification. However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of horizontal seismic design response spectrum should be considered more significantly for the frequency bands above 5 Hz.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.2
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• pp.91-100
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• 2024

Packaging method and storage time play a significant role in maintaining the quality, safety, and shelf-life of food. In this study, the quality such as acid value, peroxide value, total bacterial count, color difference, and flavor of Marsupenaeus japonicus Oranda was evaluated depending on the five packaging methods (T-N, P-N, P-O₂R, P-V, and P-N₂) and storage periods. Changes of acid value and peroxide value strongly depend on the existing oxygen of headspace in the Marsupenaeus japonicus Oranda packages. Regardless of packaging methods, the change in acid value, peroxide value, microbial growth and flavor of the Marsupenaeus japonicus Oranda occurred depending on the storage time. Especially, it is identified the quality changes of Marsupenaeus japonicus Oranda stored with P-N₂ package with less oxygen contents were retarded, compared to the them with T-N packaged with high oxygen contents.

• Journal of Life Science
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• v.29 no.12
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• pp.1378-1385
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• 2019

The nutritional composition and optimal eating stage of the super mealworm, Zophobas atratus (Coleoptera : Tenebrionidae), were investigated to explore its use as a food ingredient. It was determined that 10^th instar larvae were most suitable for eating in terms of nutritional value as well as economic aspects. To improve the quality of powder production, the nutritional value of 10^th instar larvae before and after degreasing was analyzed. After drying the larvae powder, crude protein was the most abundant nutrient both before (52.3%) and after (60.6%) degreasing while crude fat measured 36.3% and 21.7% before and after degreasing, respectively. In terms of essential amino acids, leucine levels were highest and 1.3 times greater after degreasing (4.5%) than before (3.5%). Oleic acid, the highest unsaturated fatty acid in larvae, was 31.7% after degreasing which was 1.1 times higher than before (33.2%). Among various major minerals, potassium was most abundant and 1.4 times higher after degreasing (1267.0 mg/100 g) than before (879.3 mg/100 g). Harmful substances were 1.3 to 2.0 times lower in the degreased larvae, although mercury or pathogenic bacteria were not detected in either group. We therefore conclude that degreased Z. atratus larvae are more suitable for eating than before degreasing.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.243-244
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• 2003

오존은 매우 불안정한 물질로서, 기타의 환경 대기 가스 분석법에서와 같이 해당 성분의 측정기를 표준 가스로 교정한 후 분석할 수 없다. 이러한 이유로, 환경 대기 중의 오존을 분석하는 일반 분석기의 교정을 목적으로, 본 연구실에서는, 국가 일차 오존 표준분광기(O$_3$-SRP)를 제작하여 운영하고 있다. 운영되고 있는 $O_3$-SRP의 측정 원리는 자외선 흡광 광도법이며, 농도값의 결정은 순수하게 Beer-Lambert 법칙에 따른다. Beer-Lambert 법칙에 따라서 오존 농도를 절대적으로 측정하기 위해서는 몰 흡광계수, 광로의 길이, 투과도, 온도 및 압력을 정확히 측정하여야 한다. (중략)

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.352-356
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• 2011

주로 탄화수소화합물로 구성된 EPS(Expended poly styrene)는 뛰어난 단열성능, 경제성, 건식공법의 시공편리성으로 단열재로 많이 사용되지만 화재에 취약한 단점이 있다. 최근 EPS패널의 다양한 난연화를 통해 난연EPS패널제품이 개발되고 있고 시장에서의 사용이 증가되고 있다. 그러나 가짜 난연EPS제품의 사용이 사회적 문제가 되고 있는 것도 현실이다. 본 연구에서는 난연EPS와 일반EPS가 성분이 다른점을 이용하여, 현장에서 시공되고 있는 시료의 진위여부 판단을 위해 X-선형광분석기(XRF)를 사용한 원소분석을 시도하였다. 분석결과 매우 간단한 방법으로 시료의 진위여부를 확인할 수 있었으며, 따라서 현장에서 사용될 수 있는 분석법으로 적용가능성에 대하여 고찰하였다.

• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.272-276
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• 2015

원재료 성분, 프리프레그 제작공정, 재료 취급, 부품 제작 기술, 적층순서, 환경조건, 그리고 시험방법 등 여러 요인으로 인해 복합재 물성치는 일반적으로 금속재에 비해 변동성이 높다. 따라서, 이러한 높은 변동성을 고려하기 위해서는 엄격한 통계분석기법을 적용하여 복합재의 기계적 물성에 대한 설계 허용치를 계산해야 한다. 1990년대 후반 미국에서는 FAA와 NASA를 중심으로 표준화된 절차에 따라 항공기 설계에 적용가능한 복합재 물성 데이터베이스를 구축하고 공유하기 위한 프로세스를 개발하기 시작하였고, 현재 NCAMP를 중심으로 복합재 데이터베이스 구축 작업이 진행되고 있다. NCAMP는 기본적으로 CMH-17에서 채택한 통계분석기법을 이용하여 허용치를 계산하고 있으며, 본 논문에서는 복합재 허용치 계산 기법 중 점추정 방법을 이용한 통계분석 기법과 그 적용에 대해 논하고자 한다.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.77-84
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• 2006

This study was conducted to find a system for screening organic resources with 16 species, 62 samples which were selected to randomizing point from city, province and industrial areas in the whole country. Content of organic matters were $65.3%{\sim}98.0%$ in all samples so that they were largely over than 60%, raw material regulation of compost. Concentrations of total nitrogen and total phosphorus were $0.7{\sim}4.8%\;and\;0.8{\sim}5.0$, they could look for effect of the nitrogen and phosphorus supply as a raw material of compost. In case of 8 elements concentrations of heavy metal, they were too high to use as raw materials of compost which were over to regulation limit in Cu, Cr, Ni, and As from fiber industry, Ni from food company and leather industry, and the others are adapt to limit levels. HEM contents fro the highest to $113mg\;kg^{-1}$ from liber industry and PAHs content were the highest to $3,462ug\;kg^{-1}$ from paper-mill manufacture. Distribution of PAHs concentiations were naphthalene>phenanthrene>pyrene>fluoroanthene>acenaphthene. $Microtox{(R)}\;EC_{50}$ values for bioassay were pharmaceutical company>paper-mill manufacture>industrial area sewage sludge>fiber industry>urban sewage sludge>metropolitan sewage sludge. HEM between Zn, Cu, and Ni was significant at the 99% and between Cd was significant at the 95%, Microtox between Hg and BEM significant at the 95%.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.566-574
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• 2014

This study was conducted to compare the physicochemical composition and fermentation conditions of sliced, dried radish kimchi with flying fish roe (DFFR). The levels of crude protein, crude lipid, and crude ash in DFFR were higher than those in sliced, dried radish kimchi without flying fish roe (control). DFFR also contained higher levels of Fe and Ca, compared to the control. The inosine monophosphate (IMP) content of DFFR and control was 5.63 and 2.64 mg/100 g, respectively. The polyunsaturated fatty acid and DHA contents in DFFR were approximately 5 and 23 times higher than those in the control, respectively. The major free amino acids contained in these samples were arginine, proline, alanine, leucine, and valine. The number of cells belonging to the Leuconostoc species in DFFR was higher than that in the control. In sensory evaluation studies, DFFR scored the highest in terms of appearance, flavor, taste, and texture.