• 상하수도학회지
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• 제34권3호
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• pp.183-190
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• 2020

Although membrane bio-reactor (MBR) has been widely applied for wastewater treatment plants, the membrane fouling problems are still considered as an obstacle to overcome. Thus, many studies and commercial developments on mitigating membrane fouling in MBR have been carried out. Recently, high voltage impulse (HVI) has gained attention for a possible alternative technique for desalting, non-thermal sterilization, bromate-free disinfection and mitigation of membrane fouling. In this study, it was verified if the HVI could be used for mitigation of membrane fouling, particularly the internal pore fouling in MBR. The HVI was applied to the fouled membrane under different conditions of electric fields (E) and contact time (t) of HVI in order to investigate how much of internal pore fouling was reduced. The internal pore fouling resistance (R_f) after HVI induction was reduced as both E and t increased. For example, R_f decreased by 19% when the applied E was 5 kV/cm and t was 80 min. However, the R_f decreased by 71% as the E increased to 15 kV/cm under the same contact time. The correlation between E and t that needed for 20% of R_f reduction was modeled based on kinetics. The model equation, E^1.54t = 1.2 × 10³ was obtained by the membrane filtration data that were obtained with and without HVI induction. The equation states the products of En and t is always constant, which means that the required contact time can be reduced in accordance with the increase of E.

• 한국식품과학회지
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• 제25권5호
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• pp.411-416
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• 1993

이 연구에서는 새로운 방법으로 제조된 효모 자가분해물이 쇠고기 향신료로서 이용이 가능한지 조사하기 위하여 먼저, 효모 자가분해물을 사용하여 쇠고기 맛 국물을 제조하기 위한 재료들의 최적 수준을 결정한 다음, 이를 기초로 하여 된장찌개 믹스에 사용되는 재료들의 최적 수준을 결정하였다. 최적 수준은 반응표면 방법을 사용하여 결정되었다. 쇠고기 맛 국물의 최적수준은 효모자가분해물을 8g/l, 핵산조미료는 0.8g/l, 그리고 호박산은 0.09g/l이었으며, 된장찌개 스프 믹스의 최적 수준은 쇠고기 맛 국물 재료는 8g/l, 된장분말은 28g/l, 그리고 옥수수전분은 16g/1이었다. 효모 자가분해물을 사용한 된장찌개와 소고기 분말이 첨가된 기존 제품을 사용한 된장찌개의 기호도를 비교한 결과 유의적인 차이가 없었다. 이 연구 결과 새로운 방법으로 제조된 효모 자가분해물이 된장찌개와 같은 제품에서 쇠고기 향신료로 이용될 수 있다고 본다.

• 한국식품과학회지
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• 제35권6호
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• pp.1244-1247
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• 2003

발효 및 유산균 제품에 모유만을 먹은 생후 3개월된 유아의 분변으로부터 bromocresol pule을 함유한 MRS 배지에서 노란색의 집락을 형성하는 균주들을 내산성 및 담즙산 내성이 우수한 13종의 Lactobacillus 균주들을 분리하였으며 당발효성 및 생화학적 실험을 토대로 분리된 유산균들을 동정하였다. 최종적으로 선발한 균주를 L. acidophilus로 KY1909로 명명하였다. Lactic acid 생성 능력을 평가한 후 이성질체를 분석한 결과 상업적으로 이용되는 L. acidophilus NCFM, L. acidophilus CH5, L. acidophilus NOCKS 균주들은 전체 lactic acid 중에서 L(+) form이 차지하는 비율이 각각 52.49, 40.63 및 63.13%로 나타났으나, L. acidophilus KY1909는 L(+) lactic acid의 비율이 93.96%로 나타났다.

• 한국도로학회논문집
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• 제19권6호
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• pp.105-115
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• 2017

PURPOSES : The occurrence of unexpected disasters, including fire events, increases as the road network becomes complicated and traffic volume increases. When a fire event occurs on and under bridges, the damage extensively influences direct damage to structures, vehicles, and human life and secondary socioeconomic issues owing to traffic blockage. This study investigated potential fire-hazard risks on bridges of the Korean national route road. METHODS : The investigation was conducted using field investigation and analysis with satellite pictures and road views from commercial websites and the Bridge Management System (BMS). From the filed investigation, various potential fire resources were identified. The satellite pictures and road views were helpful in measuring and recognizing conditions underneath bridges, stowage areas, etc. RESULTS : There are various potential fire resources underneath bridges such as piled agricultural products, parked petroleum tanks, construction equipment, and attached high-voltage cables. A total of 94.6% of bridges have underneath clearances of less than 15 m. A bridge underneath volume that can stow a potential fire hazard resource was $7,332m^3$ on average, and most bridges have about $4,000m^3$ of space. Based on the BMS data, the amounts of PSC and steel girders were 29% and 25%, respectively. CONCLUSIONS : It was found that the amount of stowed potential fire hazard resources was proportional to the underneath space of bridges. Most bridges have less than 15 m of vertical clearance that can be considered as a critical value for a bridge fire. The fire risk investigation results should be helpful for developing bridge fire-protection tools.

• 펄프종이기술
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• 제47권2호
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• pp.61-69
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• 2015

A number of researches have been carried out regarding the utilization of nanocellulose(crystalline nanocellulose, microfibrillated cellulose, nanofibrillated cellulose) for the manufacture of various kinds of composites and functional products. However, only few research works on the manufacturing characteristics of nanocellulose could be found, although some companies started already the production of nanocellulose in commercial scale. However, the most important thing in commercializing of production and utilization of nanocellulose is to develop the economical and efficient process. Thus, this study was carried out in order to investigate the effects of refining, alkaline pre-treatment and grinder clearance on the characteristics of microfibrillated cellulose and energy consumption. There was no significant differences in crystalline index with the degree of microfibrillation. The initial fibrillation could be improved by refining pre-treatment, but its effect was not observed anymore since the fibrillation was done up to certain level by grinding. Refining pre-treatment did not improved the energy efficiency. Alkaline pre-treatment can be helpful because the swelling of pulp fiber will facilitate fibrillation. It was found that the decrease in grinder clearance was helpful to improve the energy efficiency.

• Journal of Animal Science and Technology
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• 제62권3호
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• pp.313-320
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• 2020

This research was performed to investigate the hypothesis that dietary mono-component protease (PRO) might improve growth performance, nutrient digestibility, and carcass characteristics of growing-finishing pigs. A total of eighty-four pigs [Duroc × (Landrace × Yorkshire), 25.3 ± 2.16 kg initial body weight] were randomly assigned to three dietary treatments (7 replicates/treatment; 2 barrows and 2 gilts/replicate) in a randomized complete block design (block = sex). The dietary treatments were prepared as follows; (1) a positive control (PC) as a typical growing-finishing diet based on corn and soybean meal, (2) PC added with 0.015% of PRO (PCPRO), and (3) a negative control (NC) added with 0.015% of PRO (NCPRO). The NC had a lower concentration of crude protein (CP) compared with PC. The PRO was a commercial product that contained 75,000 protease units/g and derived from Nocardiopsis prasina produced in Bacillus licheniformis. Dietary treatments were offered to pigs during growing and finishing periods. Measurements were growth performance, apparent total tract digestibility (ATTD) of nutrients, and carcass characteristics. The PCPRO and/or NCPRO increased average daily gain (ADG) and gain to feed ratio (G:F) during growing (p < 0.10), finishing (p < 0.05), and growing-finishing periods (p < 0.10) compared with PC. Furthermore, pigs fed PCPRO and NCPRO had higher (p < 0.05) ATTD of CP and energy during growing and/or finishing periods than those fed PC. In conclusion, the supplementation of PRO in diets improved growth performance and protein digestibility of growing-finishing pigs.

• 한국의류학회지
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• 제37권1호
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• pp.17-26
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• 2013

Market available fermented indigo powders of Indian origin (FI1, FI2), Chinese origin (FC1, FC2), and raw indigo powders of Indian origin (R1, R2) were examined using TLC and HPLC analyses to investigate their pigment contents. TLC analysis gave $R_f$ values of 0.81 and 0.72 for blue and red pigments, respectively. All the powder products and the synthetic and natural indigo standards eluted at 6.9 min and 8.3 min in the HPLC chromatograms, and the peaks showed the ${\lambda}_{max}$ at 610nm and 542nm, representing indigotin and indirubin, respectively. The pigment content calculated based on the area of indigotin and indirubin peaks in the HPLC chromatograms showed that the indigotin content was higher in FC1 and FC2, while FI1 and FI2 had a higher indirubin content. The relative percentage of indirubin was the highest in R2, but the HPLC peak intensity was quite low. Despite the higher indigotin content in FC1 and FC2, cotton dyed with FI1 and FI2 (versus cotton dyed with FC1 and FC2) showed a higher blue (B) hue, the highest K/S values, and the highest antimicrobial effect.

• 지질공학
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• 제9권2호
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• pp.89-100
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• 1999

핵폐기물 처분장 공학방벽재로서의 우리나라 제 3 기층에서 산출되는 벤토나이트와 제올라이트의 활용 가능성을 물리화학적 특성을 중심으로 평가하였다. 연일 및 감포일대 제 3 기층의 9개 대표적인 벤토나이트 광산과 6개의 제올라이트 광산에서 채취한 자연산 시료와 관련회사의 추천상품시료에 대해 X-선 회절 분석, 팽윤도 측정, 양이온교환능 측정, 비표면적 측정, 몬모릴로나이트의 함량계산, 유기탄소함량 분석, 시차 열분석(DTA), 편광현미경 관찰, 주사전자현미경(SEM)관찰 및 전자현미분석(EPMA)을 실시하여 각 분석항목을 비교 평가하였다. 연구결과를 종합하면 U-41 및 G-46의 광산에서 산출되는 벤토나이트와 대도 및 Y-1호 광산의 제올라이트가 인공방벽재료로 갖추어야할 물리화학적 특성이 최적인 것으로 평가된다.

• 패션비즈니스
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• 제13권2호
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• pp.100-114
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• 2009

In Honam province, the cultural prototype are largely unknown to the people, also the research on this subject are scarce, the artistic excellence, somewhat under evaluated, both in our country and internationally. It is imperative that we develop the modern design using this prototype. thereby apply it to many areas of cultural products. We should extend the dimension not only to the local festival but also to the mass production resulting in the commercial gains. The Unjusa Buddha festival for promoting the public relation would be greatly benefited by using the concept of the temple, the local prototype, by which we expect to create a ingenious textile design pattern, coinciding with the main purpose of this study. The ancient material around Unjusa come to be the subject of our textile design by way of selecting the most remarkable ones of heritage among the materials of Unjusa. In the long run, the harmonious contrast of both traditional and modern image were sought in this study. Designed patterns were edited using Adobe Photoshop CS3, a multi-purpose graphic program and were simulated in the towel for visual presentation. The design is of two kinds, the one is of the free style using combinations of reclining Buddha, stone Buddha, stone pagoda, and geometric patterns freely not to be standardized. The other one is mixing of lotus pattern, reclining Buddha, and geometric patterns. These designs were applied delicately on the towel, necktie and handkerchief, and the various colors were suggested by the 6 color ways. The brilliance of our traditional cultural property should be noted by these designs and I hope that this study would be a help to develop our cultural prototype and make a product of using the outstanding heritage.

• 대한공간정보학회지
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• 제17권4호
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• pp.67-74
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• 2009

오픈소스 기반의 소프트웨어 개발 방법은 원시코드가 공개되어있기 때문에 개발비용이 저렴하며, 개발이 용이하다. 본 연구에서는 GeoFOSS를 기반으로 도시 내 지상시설물 관리를 위한 기본적인 GIS 기능뿐만 아니라 USN 센서에서 취득되는 각종 자료를 공간정보 상에서 처리하는 u-GIS 기능을 개발하였다. GeoFOSS를 사용하여 시스템을 구축할 경우 초기 GIS 소프트웨어 구입비용이 거의 소요되지 않아 경제적인 시스템 구축이 가능하였고, 상용 GIS 소프트웨어에서 지원하는 대부분의 기능을 구현할 수 있어 성능 측면에서도 상용제품에 비해 전혀 뒤지지 않으며, 국제 표준을 엄격하게 따를 수 있어 향후 발생할 수 있는 유지보수나 시스템 확장에 용이하고, 타 시스템과 의 상호 운용성을 확보한 시스템 개발이 가능하였다.