• Journal of Conservation Science
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• v.24
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• pp.57-66
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• 2008

It is reported that excavated carbonized wooden objects tend to have more peeling and deformation stemming from the coexisting of different types of parts of objects. However, there is little research results on this. In this experiment, the sugar alcohol method was used and then compared with the results of the PEG4000 method which widely uses. This research targets: prediction of strength by weight increase, investigation of the dimensional stabilization effects by measuring the rate of shrinkage change, condition of drug penetration and change of wood texture by using a scanning electron microscope. As the results, the PEG4000 method needs a phased approach over 80% impregnation. On the other hand, the S A method remains steady from over 40% impregnation. The Deformation of carbonized wooden objects used in this experiment is considered as the phenomenon by shrinkage of non-carbonized parts. The PEG4000 method is verified the shrinkage in the samples treated with 20%, 40% and 60%; the S A method is verified the shrinkage in the samples treated with 20%.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.57-62
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• 2012

The purpose of this paper is to find dangerous factors of a water purifier when water leaks due to inappropriate use and analyze the patterns of damaged parts in order to provide data for the examination of the cause of the problem. If the water purifier is inspected and managed by a non-specialist, when the FLC(Float Level Controller) at the top is inclined, water leakage may occur to the water purifier. The leaked water flows onto the cables and hoses and enters the thermostat terminal, heater, PCB, power supply connection connector, etc., becoming a dangerous factor that may cause a system failure, fire, etc. Due to the water that entered the input terminal, low noise and white smoke were generated at first. However, the flame gradually propagated due to the continuous inflow of moisture. It was found that when moisture reached the PCB, a carbonized conductive path was formed at the varistor terminal, input terminal, semiconductor device terminal, etc., and the flame became larger, which might result in a fire. From the metal microscope analysis of a damaged condenser terminal, it was found that the amorphous structure unique to copper cable disappeared, and voids, boundary surface and disorderly fine particles occurred. Also, in the case of the connector into which moisture penetrated, fusion and deformation occurred at the cable connection clips. The result of analysis of the power supply cable connector using a thermal image camera showed that most of the heat was generated from the cable connection clips and the temperature at the connection center was normal.