• Journal of KSNVE
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• v.7 no.3
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• pp.499-509
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• 1997

During the process of oxide removal from work rolls in sheet metal manufacture, filamentary brushes frequently exhibit a bouncing or chatter behavior. The dynamics of this phenomenon is investigated through the development of expressions for the non-linear contact stiffness between the brush and the roll. With formulation of simple structural models, the time responses in the presence and absence of friction under random excitation are investigated. Possible solutions for the minimization or avoidance of this bouncing or chatter problem are also suggested.

• International journal of steel structures
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• v.18 no.5
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• pp.1631-1638
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• 2018

In the periodic repainting of steel bridges, often the steel surface has to be prepared by using power tools to remove surface contaminants, such as deteriorated paint film and rust, and to increase the adhesive strengths of the paint films to be applied newly. Surface preparation by bristle roll-brush grinding, which is a type of power tool, may additionally introduce compressive residual stress and increase the fatigue resistance of welded joints owing to the impact of rotating bristle tips. In this study, fatigue tests were conducted for longitudinally out-of-plane gusset fillet welded joints and transversely butt-welded joints to evaluate the effect of bristle roll-brush grinding prior to repainting on the fatigue resistance of the welded joints. The test results showed that bristle roll-brush grinding introduced compressive residual stress and significantly increased fatigue limits by over 50%.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.342-345
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• 2009

Electro galvanized steel is electroplated cold roller steel for improving corrosion resistance and paintability, and is widely used in automobiles and home appliances. In the electroplating line for manufacturing electro galvanized steel if plating process is carried out with impurity on conductor roll surface, the defects in manufacturing process occurs because of steel fault. For quality, polishing is always required to separate impurity on surface of conductor roll. In this study, finite element analysis of wear for polisher brush is carried out for replaced time of it.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.9
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• pp.1062-1069
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• 2011

In electro-galvanizing line to manufacture the electro-galvanized steel sheet, polishing system is required to maintain clean surface of conductor roll and to secure the quality of the steel sheet. At the same time, prediction and decision of the replacement cycle for felt material and its brush installed in the polishing system is also important because the brush is directly contacted on the conductor roll surface. In this study, the polishing system has been designed which the brush is repetitive translating according to the longitudinal direction of the conductor roll. Furthermore, the prediction on the wear-life of the felt material used for the brush is performed using the contact pressure extracted by finite element analysis. And to verify the predicted wear-life of the felt material, the experimental study is also carried out. From the comparison result between the predicted and the measured wear-life of the felt material, it is presented that the wear-life and the replacement cycle of the felt material are well predicted by considering a wear compensation factor, and the wear compensation factor is useful and reasonable.

• Journal of Power System Engineering
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• v.14 no.4
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• pp.5-10
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• 2010

This study was investigated the effect on operating characteristics of apparatus according to frosting and defrosting to develop of new defrosting equipment. The results showed as following. Frost was almost removed using the defrosting equipment with roll brush type that defrosting is possible under operating condition. Also, the temperature of compressor inlet, evaporator inlet and outlet showed higher value because of heat transfer resistance of cooling pipe frost comparing with defrosting condition. And the compressor work showed 10% lower and COP was presented 24% higher values than defrosting condition. Therefore, defrosting for cooling coil of refrigeration and low temperature storage was effected on operation and performance characteristics of equipment. This highly effects on real refrigeration apparatus which is operated in year-around.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.795-801
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• 2010

As the fabrication technology of LCDs (Liquid Crystal Displays) advances, the size of mother glass substrates is getting larger, and the fabrication process is becoming finer. Accordingly, the importance of cleaning processes grows in the fabrication process of LCDs. In this study, we have compared and evaluated the particle removal efficiency for three different methods of physical cleaning, which are brush, bubble jet, and aqua/air cleaning. Using the seventh generation glass substrate, the particle removal efficiency has been investigated by changing operation conditions such as a flow rate of deionized water, pressure, contact depth between a brush bristle and a glass substrate, and so forth. In the case of brush cleaning, the cleaning efficiency barely changes after a critical point when the contact depth is varied. While the cleaning efficiency of bubble jet cleaning is almost independent of pressure, that of aqua/air cleaning is affected by pressure up to a critical point, but is not changed after it. We note the brush cleaning is the most effective among the three cleaning methods under our experimental conditions.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.433-439
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• 2004

Hanji costumes has four aspects that allow the creator or artist to create many variations. The pictorial effects of Hanji costumes are produced through variations in the dyes and brushes used for its application. The amount of water and texture of the Hanji mixture also influences the Hanji clothing. This effect was expressed using a dry brush technique, a dripping technique, India inks, and fragments from other Hanji works. A second aspect of Hanji clothing is the coloring effect in the Hanji costumes. The coloring is due to the fibers in the preparation mixture and the uniqueness of the dyes. The Hanji clothing was dyed various colors and patterns by dip dyeing, block dyeing, silk screens, digital printing. The third aspect of Hanji imagination in clothing is the decorative details. The details in Hanji clothing can be seen using frills, pleats, tucks and ribbons. The last variation of Hanji clothing can be expressed through crafting techniques. These techniques are the quality of paper string, cuts in the paper and paste ingredients. With Hanji cloth, it is possible to plait, roll, and crample into other flexible & useful materials.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2459-2467
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• 2010

The purpose of this study was to survey visiting health care personnel who worked for their public medical health institutions and thereby investigate their oral health knowledge and behavior. Findings of this study are summarized as follow; First, our visiting health care personnel had a significant tendency toward higher score at correct answers to questions about oral health knowledge (mean knowledge about periodontal disease: 67%, mean knowledge about dental caries: 68%, mean knowledge about common dentistry: 68.4% or higher). Secondly, in terms of oral health care behavior, 50% or higher of all our visiting health care personnel visited dental clinic for preventive purposes, and 60.1% visited dental clinic for oral treatment. 46.6% of health care personnel relied on dental clinic for regular scaling services, and 89.6% relied on general hospital or dental clinic for oral treatment. 89.5% of health care personnel brushed their teeth 3 times or more per day; more than half (58%) of them preferred dental floss to other oral hygiene supplies; and 46% practiced roll technique to brush their teeth. Thirdly, health care personnel's oral health knowledge was significantly correlated with their age (F=5.25, p<0.01) and career of health care (F=3.94, p<0.01), while their oral health behavior was significantly associated with their career of visiting health care (F=3.20, p< 0.05).