• Proceedings of the Korea Fashion and Costume Design Association Conference
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• autumn
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• pp.121-125
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• 2004

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.10 no.2
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• pp.113-116
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• 2005

• Proceedings of the Plant Resources Society of Korea Conference
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• 2001.04a
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• pp.80-82
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• 2001

• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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• pp.99-107
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• 2008

There are being a lot of studies for achievement of high speed Dehydration, high-strength and Lightweight of washing machine in the latest washing machine business. It is essential that strength of mechanical press-Joining (MPJ) for spin drum is improved to attain that target. MPJ of spin drum is composed of seaming and caulking process. Because Seaming process of MPJ has various design factors such as thickness, bending radius, seaming width, caulking press width and the dynamic factor such as multistage plastic working, elastic recovery, residual stress, the optimum conditions can't be easily determined. Using a design of experiment (DOE) based on the FEM (Finite Element Method), which has several advantages such as less computing, high accuracy performance and usefulness, this study was performed investigating the interaction effect between the various design factor as well as the main effect of the each design factor during drum MPJ and proposed optimum condition using center composition method among response surface derived from regression equation of simulation-based DOE.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.5
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• pp.132-139
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• 2008

To meet demand of big capacity and high speed rotation for washing machine, more stress from bending and twisting are complexly loaded onto the shaft supporting the horizontal drum, causing problems in fracture strength and fatigue life. Also, Vibration occurs due to the frequency of the rotating parts. But, shaft has various design factors such as diameter and distance between bearings according to configuration of shaft, the optimal values can't be easily determined. Using a design of experiment (DOE) based on the FEM (Finite Element Method), which has several advantages such as less computing, high accuracy performance and usefulness, this study was performed investigating the interaction effect between the various design factor as well as the main effect of the each design factor under bending, twist and vibration and proposed optimum design using center composition method among response surface derived from regression equation of simulation-based DOE.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1746-1754
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• 2016

Recently, spherical beads entrapping quorum quenching (QQ) bacteria have been reported as effective moving QQ-media for biofouling control in MBRs for wastewater treatment owing to their combined effects of biological (i.e., quorum quenching) and physical washing. Taking into account both the mass transfer of signal molecules through the QQ-medium and collision efficiencies of the QQ-medium against the filtration membranes in a bioreactor, a cylindrical medium (QQ-cylinder) was developed as a new shape of moving QQ-medium. The QQ-cylinders were compared with previous QQ-beads in terms of the QQ activity and the physical washing effect under identical loading volumes of each medium in batch tests. It was found that the QQ activity of a QQ-medium was highly dependent on its specific surface area, regardless of the shape of the medium. In contrast, the physical washing effect of a QQ-medium was greatly affected by its geometric structure. The enhanced anti-biofouling property of the QQ-cylinders relative to QQ-beads was confirmed in a continuous laboratory-scale MBR with a flat-sheet membrane module.

• Food Science and Preservation
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• v.20 no.6
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• pp.751-759
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• 2013

There is increasing interest in freshly cut products, that is, foods produced without washing and cutting. In this study, the quality of freshly cut sliced Deodeok was compared with that of what based on its washing methods. In bubble washing, the Deodeok rises to the water surface apace and is broken into centimeter sizes. Microbubble washing calls for the production of a great number of 0.1 mm-sized bubbles in anions-bearing water and their passing through a trumpet-shaped hole at a high pressure. To compare the product deterioration rates of the specimens, they were stored at $10^{\circ}C$ for 10 days. In the specimens washed with the control method and with hand washing, the deterioration rate was 80%; and in the specimens washed with bubble and microbubble washing, 20~30%. The L-value (an index of browning) was higher in the bubble and microbubble washing than in the control and the hand washing, which implies that browning was minimized during the storage. As for the viable cell and coliform group counts that were measured during the storage, the specimens washed with the control method showed the highest values. In contrast, the specimens washed with microbubble washing showed the lowest values. In the sensory test, the specimens washed with microbubble were highest in storage preference. In conclusion, the Deodeok that was stored after it was washed with microbubble washing was found to have had the best quality.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.30-36
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• 2012

This study was conducted to evaluate the microbiological hazard on nursery school children's hands and to investigate the reduction effect of hand washing education. A total of 59 nursery school children's hands were tested. The average number of total aerobic bacteria was $3.72{\pm}0.38log\;CFU/hand$. Five children's hands(2 male and 3 female) were positive(14.3%) for the coliform bacteria. These results showed that hand washing education are required repetitively. Among the pathogenic bacteria tested in this study, $Staphylococcus$ aureus and $Bacillus$ $cereus$ were detected in 9(25.7%) and 16(45.7%) out of 35 their hands, respectively. Twelve out of sixteen $B.$ $cereus$ isolates(70.0%) produced enterotoxin. The results indicate that the hand hygiene of nursery school children needs to be improved. Comparing before and after hand washing in educated and non-educated group, the reduction effect of total aerobic bacteria on their hands was 0.42 and 0.60 log CFU/hand, respectively. The educated group showed 0.18 log CFU/hand higher reduction effect than non-educated group but microorganism did not eliminate perfectly. From the results, using a hand sanitizer after washing with soap and the continuous hand washing education are required to control the contaminated bacteria on nursery school children's hands.

• Journal of Biosystems Engineering
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• v.30 no.1 s.108
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• pp.17-24
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• 2005

An efficient microbial control system was introduced into a garlic peeling system using pressurized water in order to improve the quality and the shelf-life of peeled garlic. High microbial density of the spoiled peeled garlic and the water used for peeling and washing indicated that an efficient microbial control system is necessary far the peeling system. Though Pseudomonas spp. and Penicillium spp. were closely related to the spoilage of peeled garlic, the spoilage of peeled garlic was thought to be caused mainly by nonspecific increase in microbial density. The shelf-life of the garlic peeled by pressurized water was longer than that of the garlic peeled by pressurized air, and the degree of damage had great effect on the shelf-life of peeled garlic. Ozonated water was effective in decreasing the microbial contamination and in increasing the shelf-life of peeled garlic. Based on the findings of the study, following improvements were made to the garlic peeling system using pressurized water; 1) the water circulation system was modified in order to completely separate the water for washing from the water for garlic peeling, 2) filtration and cooling equipments were introduced into the circulation system of the water for peeling, and 3) an ozone generator which could continuously supply ozonated water (dissolved ozone concentration of 0.4 ppm) was attached to the circulation system of the water for washing.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.503-509
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• 2018

Endive is widely consumed in a fresh-cut form owing to its rich nutritional content. However, fresh-cut vegetables are susceptible to contamination by pathogenic bacteria. This study investigated the antibacterial activities of the combined treatment of cinnamon leaf oil emulsion containing cetylpyridinium chloride or benzalkonium chloride (CLC and CLB, respectively) as a cationic surfactant and ultrasound (US) against Listeria monocytogenes and Escherichia coli O157:H7 on endive. The combined treatment of CLC or CLB with US reduced the population of L. monocytogenes by 1.58 and 1.47 log colony forming units (CFU)/g, respectively, and that of E. coli O157:H7 by 1.60 and 1.46 log CFU/g, respectively, as compared with water washing treatment. The reduction levels of both pathogens were higher than those observed with 0.2 mg/ml sodium hypochlorite. In addition, the combined treatment showed no effect on the quality of the fresh-cut endive (FCE). In particular, the degree of browning in FCE was less for the treatment group than for the control and water washing treatment groups. Thus, cationic surfactant-based cinnamon leaf oil emulsions combined with US may be an effective washing treatment for the microbial safety of FCE.