• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.208-210
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• 2008

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.583-584
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• 2009

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.571-573
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• 2009

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.72-74
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• 2007

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.243-245
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• 2006

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.749-750
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• 2007

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.591-593
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• 2010

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.1
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• pp.37-44
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• 2012

This paper describes energy loss in a pipe line of refuse collecting system. Analysis of energy loss in a pipe line is the decisive factor in a design of refuse collecting system. Using the results of energy loss analysis, we can determine the power of turbo-blower. The flow characteristics of the pipe line with refuse bags were analyzed by three-dimensional CFD. The refuse bag is modeled by using the shape obtained from profile measurement. Friction factors were calculated with changing the refuse bag size, mixing ratio and Reynolds number. And drag coefficients were calculated using the CFD results. From the results we can calculate energy loss in a pipe line of refuse collecting system and predict the capacity of turbo-blower.

• Journal of Environmental Science International
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• v.20 no.1
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• pp.25-34
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• 2011

The new empirical static model was constructed on the basis of dimension analysis to predict the pressure drop according to the operating conditions. The empirical static model consists of the initial pressure drop term (${\Delta}P_{initial}$) and the dust mass number term($N_{dust}=\frac{{\omega}_0{\nu}_f}{P_{pulse}t}$), and two parameters (dust deposit resistance and exponent of dust mass number) have been estimated from experimental data. The optimum injection distance was identified in the 64 experimental data at the fixed filtration velocity and pulse pressure. The dust deposit resistance ($K_d$), one of the empirical static model parameters got the minimum value at d=0.11m, at which the total pressure drop was minimized. The exponent of dust mass number was interpreted as the elasticity of pressure drop to the dust mass number. The elasticity of the unimodal behavior had also a maximum value at d=0.11m, at which the pressure drop increased most rapidly with the dust mass number. Additionally, the correlation coefficient for the new empirical static model was 0.914.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.41-49
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• 2014

The research was performed to investigate the weathering characteristics of fruit growth paper bags. The bags were used to cover fruits such as grapes and pears. And then they were collected after 30 and 60 days exposure at the orchard. The physical and optical properties of the bags tended to decrease with the exposure times. The larger change on the properties were found on the papers exposed for 30 days. The cover paper for pear showed the largest density changes. The air permeability were decreased with the exposure time in all bags. The cover paper for pear showed the very low values of air permeability. The mechanical properties of the fruit bags showed to be gradually decreased with the length of exposure time. The tear index showed the largest differences. The cover paper for pear showed the rapid decrease on the mechanical properties after 60 days of the exposure. The inner paper, however, showed the strength enough to cover the fruits. The precipitation showed more effect on the degradation of fruit growth paper bags than the light hours.