• Journal of Korean Society of Water and Wastewater
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• v.34 no.3
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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.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.411-416
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• 1993

This study was conducted to determine optimum levels of ingredients including yeast autolyzate, first for the beef flavored soup base and then for the soy paste stew mix as a final product. Response surface methodology was used for the optimization. Beef flavored soup base with optimum sensory characteristics could be prepared with 8g/l yeast autolyzate, 0.8g/l nucleotide seasoning, and 0.09g/l succinic acid. And soy paste stew mix could be produced with 8g/l beef flavored soup base, 28g/l soy paste powder, and 16g/l corn starch. Soy paste stew prepared with optimum levels of ingredients were comparable in acceptability to that with commercial product containing beef extracts. It was suggested that sufficient beef flavor could be obtained with yeast autolyzate in such products as soy paste stew mix.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1244-1247
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• 2003

The purpose of this study was to isolate lactic acid bacteria that produced L(+) lactic acid from infant feces. Thirteen colonies were isolated with a MRS-plate containing 0.5% $CaCO_3$ to determine their ability to produce lactic acid. Based on their lactic acid production, 10 strains of Lactobacillus were identified to assess the ratio of lactate isomer using HPLC. A strain producing L-lactic acid was identified as Lactobacillus acidophilus, using API carbohydrate fermentation patterns and physiological tests, and named KY1909. The strain exhibited good acid tolerance in an artificial gastric juice as well as high bile resistance in MRS containing 0.5% bile acids. L. acidophilus KY1909 produced D(-) and L(+) lactic acid at a ratio of 6 : 94; whereas commercial strains of Lactobacillus acidophilus produced D(-) and L(+) lactic acid at a ratio of 1 : 1. These results demonstrate the L. acidophilus KY1909 can be utilized in fermented milk products and dietary supplements as a probiotic culture.

• International Journal of Highway Engineering
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• v.19 no.6
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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.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.2
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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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• v.62 no.3
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.1
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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.

• The Journal of Engineering Geology
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• v.9 no.2
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• pp.89-100
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• 1999

This study was carried out to assess the physicochemical properties of domestic bentonites and zeolites from Tertiary Formation as the candidate material for a engineered barrier of a radioactive waste repository. Natural bentonite and zeolite samples were collected from nine bentonite mines and six zeolite mines in Yeonil-Gampo area. The commercial products of bentonite and zeolite were obtained from local companies. The collected samples were investigated to study the following physicochemical properties: X-ray diffraction patterns, swelling, cation exchange capacity(CEC), specific surface area, montmorillonite content, pH, organic carbon content, thermal property, microstruciure and chemical composition. Based on the physicochemical properties of bentonite and zeolite, the bentonites from U-41 and G-46 mines and the zeolites from Daedo and Y-1 mines are regarded as the most desirable candidate materials.

• Journal of Fashion Business
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• v.13 no.2
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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.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.4
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• pp.67-74
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• 2009

The 'Open Source' of programing is a method that is not only sharing the source, but also making the S/W by the low cost and easy way. In this study, we made the urban facilities management system(FMS) based on the GeoFOSS of Open Source. This system has the GIS function of the urban facilities management, the u-GIS function using the USN for processing the spatial information. Also, as we use the GeoFOSS of 'Open Source', we can have received many benefits. First, this system has the economic impact, because it is not necessary to buy the commercial GIS software. Second, this system can make most functions of the GIS, the performance does not bad compared to other products. Also, this system strictly conforms to the international standards, it is easy to get a repair, maintenance and interoperability.