• Journal of Korean Society of Environmental Engineers
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• v.33 no.3
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• pp.191-195
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• 2011

The measurement and prediction of bacterial transport of bacteria in aquatic systems is of fundamental importance to a variety of fields such as groundwater bioremediation ascending urinary tract infection. The motility of pathogenic bacteria is, however, often missing when considering pathogen translocation prediction. Previously, it was reported that flagellated E. coli can translate upstream under low shear flow conditions. The upstream swimming of flagellated microorganisms depends on hydrodynamic interaction between cell body and surrounding fluid flow. In this study, we used a breathable microfluidic device to image swimming E. coli at a glass surface under low shear flow condition. The tendency of upstream swimming motion was expressed in terms of 'A' value in parabolic equation ($y=Ax^2+Bx+C$). It was observed that high shear flow rate increased the 'A' value as the shear force acting on bacterium increased. Shorter bacterium turned more tightly into the flow as they swim faster and experience less drag force. The result obtained in this study might be relevant in studying the fate and transport of bacterium under low shear flow environment such as irrigation pipe, water distribution system, and urethral catheter.

• Journal of radiological science and technology
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• v.14 no.2
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• pp.15-21
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• 1991

Experiment was conducted on the image quality and exposure dose following replacement of $CaWO_4$ system screen BH-III and BX-III which have so far been used for high-voltage hard-radiation quality radiography, with rare earth system screen KO750, combined with high contrast film SRH, while additional filter was altered, Cu 0.8 mm+Al 1.4 mm(HVL : Al 8.8 mm), Cu 1.3 mm+Al 1.0 mm(HVL : Al 10.6 mm) and Cu 1.8 mm+Al 1.5 mm(HVL : Al 11.4 mm). AS a result, visual evaluation did not detect extreme changes in image quality under the respective condition(HVL : $Al\;8.8\;mm{\sim}Al\;11.4\;mm$). It was noted, however, that surface exposure dose declined with an increase in the thickness of the additional filter, as it was $18.9\;{\mu}Gy$ at HVL Al 8.8 mm, $17.5\;{\mu}Gy$ at Al 10.6 mm and $15.7\;{\mu}Gy$ at Al 11.4 mm. Considering the limited rating of X-ray equipment and wear of machinery, however, the range of $Cu\;1.3\;mm{\sim}1.8\;mm+Al\;1.0\;mm{\sim}1.5\;mm(1/16\;VL{\sim}1/32\;VL)$ seemed to be a limit.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.543-549
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• 2016

The objective of this study was to investigate quality properties of 'Cheonghyang' wine using different commercial yeast strains. Soluble solid content, pH level and total acidity of 'Cheonghyang' grape were $20^{\circ}Bx$, pH 3.5 and 0.66%, respectively. Total acidity ranged from 0.91~1.06% in the middle stage of fermentation and decreased to 0.77~0.82% when alcoholic fermentation finished. Alcohol content in wines ranged from 12.5% to 12.9% showing no significant difference in yeast strains. Wine fermented with Red Fruit had high volatile acid content (189.0 mg/L) whereas wine fermented with Fermivin indicated low volatile acid content (77.7 mg/L). Wines made with Montrachet, Fermivin and Aroma White had low brightness (L-value) compared to others. Results from sensory evaluation demonstrated that commercial wine yeasts, Montrachet and Fermivin, can be applied to improve sensory properties of 'Cheonghyang' wine such as aroma, acidity and transperency. On the other hand, preferences of wine fermented with EC-1118 strain containing lots of tannins and total polyphenols were significantly reduced.

• Current Photovoltaic Research
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• v.9 no.2
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• pp.45-50
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• 2021

Agrovoltaic system is a concept that combines agriculture and photovoltaic (PV) system by applying a PV system to the upper part of farmland. In this study, we developed a folding drive system for an agrophotovoltaic (agroPV) module (150 Wp/4×9 cell) exclusively for pear farming with 10 kW capacity. The system was installed in 2018, and the growth characteristics and quantity of pears under the agroPV folding system have been investigated for 2 years. We found that thare is no differences of the characteristics of pears grown under the agroPV system compared to the pears grown without the system (control) except the percutaneous color L of pear. However, the weight and sugar content of the pear grown under the agroPV system were decreased by 4.5% and 1.3°Bx compared to that of the control, respectively. We assume that this is mainly due to the influenced of the delay in flowering as upper PV module block some of sunlight. However, interestingly, when we deleyed the pear harvesting by 2 weeks, the weight of pears increased by 8.5% and they became nearly the sample as the control pears harvested 2 week earlier. In addition, we also found that the agroPV modules decrease the fall rate of pear when the typoon struck, also it mitigates cold damage by 38% during April by protecting from frost. In conclusion, it can be said that the agroPV system help to protect target crops from the environmental conditions and the quality of the crops are similar to the that of control.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.261-265
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• 1992

To improve preservation and utilization of radish juice concentrates, radish juice were concentrated by reverse osmosis(RO) and thin layer evaporator(TLE) and their rheological properties were investigated. Radish juice concentrates were considered as nowtonian fluids. The apparent viscosity of conc. 1 (Heat treatment radish juice, concentrated by TLE), conc. 2 (Raw radish juice, concentrated by TLE), conc. 3 (Heat treatment radish juice, concentrated by RO) were 0.0503, 0.0578 and 0.0655 Pa.s at 10(1/s), respectively. The yield stress of these concentrates were ranged from 0.0001 to 0.0580 Pa. The activation energy for the flow of the radish juice conc. 1 were increased from 2.7057 to $4.1159{\times}10^4KJ/kg.mol$ by increasing concentration of radish juice.

• Journal of the Korean Geotechnical Society
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• v.15 no.6
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• pp.155-165
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• 1999

In completely weathered granite gneiss,8 of 40cm cast-in-situ concrete piles are constructed, and static pile load tests are executed on the piles to study the bearing behavior of rock-socketed piles. Subsurface explorations are carried out on the test site in three phases, in which 14 borehole investigations as well as the seismic investigation are performed. Rock socketd depths of the piles in the weathered rocks are varied as 3m, 6m and 9m to separate the shaft resistance from the end bearing resistance, and for a couple of piles, styrofoam of 10cm thickness is installed under the pile point to eliminate the effect of the end resistance. Strain gages are instrumented on re-bars to pick-up the transferred loads along the pile length. From the results of the pile load tests, the allowable shaft resistance and the allowable end bearing values of weathered rocks are proposed as $8.6t/m^2\;and\; 84t/m^2$, respectively. The empirical equation relating the elastic modulus of rock mass with the uniaxial compressive strength of the rock specimen is also proposed for the weathered rocks.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.737-746
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• 2012

본 연구는 mushroom complete medium(MCM) 액체배지에 수삼 추출물(GE, $65^{\circ}Bx$)을 첨가하여 면역활성이 증진된 노루궁뎅이버섯(Hericium erinaceum) 균사체를 배양하고, 균사체로부터 활성다당성분을 분획하고자 하였다. MCM에 대하여 GE를 5, 10과 15%(v/v) 첨가한 액체배지에서 균사체를 배양하고, 각각의 조다당획분(HE-GE-5-CP, HE-GE-10-CP와 HE-GE-15-CP)으로 분획하여 면역활성을 측정한 결과, HE-GE-10-CP는 HE-GE-5-CP와 HE-GE-15-CP보다 높은 활성을 나타내었으며, GE를 첨가하지 않은 MCM에서 배양된 균사체 조다당획분(HE-CP)보다 유의적으로 증진된 면역활성을 나타내었다. 또한, HE-GE-10-CP의 DEAE-Sepharose CL-6B 분획물 중 가장 높은 활성을 나타낸 HE-GE-10-CP-II획분은 대조군인 HE-CP의 어떠한 획분보다도 유의적으로 높은 면역활성과 암 전이 억제활성을 나타내었다. 한편, 활성획분인 HE-GE-10-CP-II는 arabinose, rhamnose, galactose, glucose와 uronic acid(molar ratio; 0.34:0.26:0.99:1.00:0.39)로 구성되어 있으나, 대조군인 HE-CP의 동일용매 용출획분으로서 HE-GE-10-CP-II보다는 활성이 낮은 HE-CP-II는 fucose, mannose, galactose와 glucose(molar ratio; 0.32:0.55:1.00:0.96)를 함유하여 다른 구성당 분포를 나타내었다. 따라서 노루궁뎅이버섯 균사체 액체배양에서 수삼 추출물 첨가는 균사체의 구성당 변화를 통한 면역활성 증진에 관여하는 것으로 사료되어 기능성 소재 개발에 유용할 것으로 사료된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1090-1094
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• 2008

Treatment effects of grape fruit stem extracts (GFSE) containing trans-resveratrol or fermented pollen (FP), and ethylene gas scavenging material (EGS) on the storage property of fresh jujube (Z izyphus jujuba forma hoonensis C.S. Yook) were investigated. Fresh jujubes were packed in different storage containers (PE film and Lock & Lock vessel), and treated with GFSE containing trans-resveratrol of 30 ppm or 1% FP, and EGS. The storage vessels were stored in refrigerator ($0{\pm}1^{\circ}C$) during 12 weeks, and then quality characteristics during storage period were analysed. Hardness slightly increased until 4 weeks and decreased afterward. Soluble solid ($^{\circ}Bx$) and total titratable acidity of fresh jujube slightly increased in all treatments during storage period. Vitamin C content of fresh jujube slightly decreased in all treatments during storage period. Number of microorganisms decreased until 4 weeks and increased afterward. The decay enzyme activity increased in all treatments during storage period. Storage stability was higher for PE film than Lock & Lock containers. Storage period of fresh jujube in this experiment ranges in $8{\sim}9$ weeks for maturity fruits treated with 30 ppm of GFSE and ethylene gas scavenging material.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.119-125
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• 2010

This study was carried out to compare the physicochemical characteristics of Korean traditional wine fermented from proso millet and nuruk at different mixing rate. The alcohol contents of the fermented wine ranged from 12.36 to 13.21%. Two kinds of nuruk, SH and BS nuruks were used. The brix degrees of proso millet wine fermented by SH and BS nuruks were 21.6 and 22.4 $^{\circ}Bx$, respectively. The pH, total acidity, and turbidity the wines fermented by SH and BS nuruks were 3.74 and 3.40, 1.40 and 1.51%, and 0.441 and 0.149, respectively. With increasing the addition amount of proso millet, brix degree, pH, turbidity L-value decreased, and total acidity and avalue increased. Total color difference (${\Delta}Eab$) parameter of the wine fermented by SH nuruk were 4.33, 6.63 and 26.13, and by BS nuruk were 4.08, 5.29 and 10.59 in 30, 70 and 100% addition rates of proso millet. With increasing the addition amount of proso millet, glucose content decreased. The organic acids such as lactic acid and acetic acid were predominantly detected in the fermented wine. Finally, based on sensory evaluations, the wine fermented by SH nuruk showed the best overall quality at 30% addition rate of proso millet.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.207-215
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• 2012

Six different mashing types ((A) $koji$+purified enzyme, (B) $koji$+crude enzyme, (C) $koji$+$nuruk$, (D) $koji$+purified enzyme+$nuruk$, (E) $koji$+crude enzyme+$nuruk$, (F) purified enzyme+$nuruk$) had been established, according to fermentation agents and a mixing rate of rice $makgeolli$, in this study. The alcohol content was the highest in the mashing type (C), which was 13.6%, followed by (D) 13.5%, (A) 13.1%, (B) 12.9%, (E) 12.7% and (F) 12.1%. The reducing sugar content of (A) was the highest with 401.6 mg% and those of (B), (C), (D) and (F) were between 337.3- 380.9 mg%. The alcohol components were found and tended to increase during the fermentation. The oligo-saccharides content was the highest in (D) with 1251.3 mg%, which was followed by (E) 1,219.2 mg%, (C) 1,141.4 mg%, (A) 1,049.9 mg% and 973.8 mg% in (B). The total free amino acid was highest in (B) with 781.4 mg% and followed by (C) 703.2 mg%, (D) 702.6 mg%, (E) 678.7 mg%, (A) 630.4 mg% and (F) 328.7 mg% in order. There were 16 different types of volatile flavor components, in the mashing types (A) and (B), in addition to 15 different types of those in type (C), as well as 14 different types of those in (D), (E) and (F). There were significant differences in the overall preference between the type (A) and (C).