• Journal of the Korean Wood Science and Technology
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• v.36 no.2
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• pp.39-45
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• 2008

Formaldehyde and volatile organic compounds (VOCs) are emitted from wood-based panels that have been made using wood particles, wood fiber, wood chips, formaldehyde-based resins and so on. In this study, we examined formaldehyde and total VOCs (TVOC) emission behaviors for plywood overlaid with water-soluble phenolic resin impregnated linerboard (PL), and two kinds of surface materials (decorative veneer and pre-impregnated finishing foil) that were adhered onto the PL that named DPL and PPL. EVA (ethyl vinyl acetate) was used to overlay the decorative veneer and pre-impregnated finishing foil on the plywood with water-soluble phenolic resin impregnated linerboard by a hot press instrument. The debonding test and accelerated aging test were conducted to assess their mechanical properties. Formaldehyde and TVOC emission concentrations were measured using the FLEC method and a VOC Analyzer, respectively. The debonding test results of PL, DPL and PPL were 1.2, 1.5, and $0.5N/mm^2$, respectively. The surface appearance of the samples were not changed after the accelerated aging test. The PL and DPL exhibited reduced formaldehyde and TVOC emission levels, respectively. In the case of PPL, the VOC value was relatively higher than those of PL and DPL.

• Textile Coloration and Finishing
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• v.21 no.4
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• pp.46-56
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• 2009

In order to establish the standard manufacturing condition of PET flame retardant sheets, physicochetnical properties of the samples made by the conventional flame-retardant finishing were systematically investigated, including compatibility among flame retardant agent and finishing auxiliaries, surface property, and wicking property. From this results, the addition of washing and renapping process after the shearing process was required for the more effective in producing PET flame-retardant sheet by the standard finishing. The effect of the modification of the regular flame retardant finishing process was studied by FTIR, TGA, and flame retardancy test.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.1
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• pp.47-54
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• 2004

In this study, the electrorheological (ER) fluid was used as finishing agent. Since the apparent viscosity can be controlled by an electric field, the ER fluid can be one of efficient materials in finishing processes. To finish small 3-dimensional structures such as the aspherical surface in optical elements, the possible arrangement of a tool, part and auxiliary electrode was described. We examined the influence of the addition of a few abrasive particles on the performance of the ER fluid by measuring yield stress and observed the behavior of abrasive particles in the ER fluid by a CCD camera, which had been also theoretically predicted from the electromechanical principles of particles. On the basis of the above results, the steady flow analysis around the rotating micro tool was performed considering the non-uniform electric field. Finally, borosilicate glass was finished using the mixture of the ER fluid and abrasive particles and material removal with field strength and surface roughness were investigated.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.488-502
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• 2020

In this study, the moisture absorption and desorption properties presented by the Health-Friendly Housing Construction Standards of South Korea were compared using the wood of three tree species (Douglas-fir, Hinoki, Larch) and two types of wood-based materials(Plywood, WML Board^Ⓡ). The national standards for functional building materials present that the amounts of moisture absorption and desorption should be at least 65g/㎡ on average, respectively according to the test method under KS F 2611:2009. Therefore, in this study, the moisture absorption/desorption properties of materials with no treatment (Control), with punching, and with surface stain finishing and the moisture absorption/desorption property improvement effects of the treatments were compared and analyzed. According to the results of this study, it was evaluated that all five types of wood and wood-based materials tested did not satisfy the amount of moisture absorption/desorption of at least 65g/㎡, which is the performance standard for moisture absorption/desorption functional building materials, indicating that untreated wood and wood-based materials cannot be applied as functional finishing materials according to the Health-Friendly Housing Construction Standards. The surface stain finishing greatly reduced the moisture absorption and desorption rates of the materials, and the amounts of moisture absorbed and desorbed were also shown to decrease by at least two times on average. When the surfaces of the materials were punched with Ø4mm holes at intervals of 20 mm, the moisture absorption/desorption areas increased from 18% to 51%, and this increase was shown to be capable of increasing the amounts of moisture absorbed/desorbed by 29% on average at the minimum, and 81% on average at the maximum. The effects of punching were shown to be identical even in cases where the materials were stain finished. For the application of wood or wood-based materials as eco-friendly, health-friendly, and moisture absorption/desorption functional building materials hereafter, it is judged that new physical and chemical improvement studies should be conducted, and treatment methods should be developed.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.4
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• pp.37-44
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• 2023

Purpose: Currently, research on environmental conditions and finishing materials for medical facilities with proven antiviral performance is poor in Korea. Through this study, we have explored environmental characteristics and finishing materials that can be used to control cross-infection when constructing medical facilities. Methods: Experiments in overseas papers related to antiviral effects of environmental conditions, spatial compartments, and interior finishes have been analyzed. Results: The higher the temperature, the higher the humidity, and the higher the illuminance of sunlight, the lower the viability of the corona-virus. The proliferation of viruses was suppressed on the surface of the copper alloy. Materials such as brushed steel are the ones that maintain the strongest viability. Among the characteristics of the surface, survival and propagation power differ depending on whether it is porous or hydrophilic. In the case of infection ward actually operated in Italy, the presence of airborne viruses in contaminated and non-contaminated spaces differed significantly. Corona-virus has been identified in reachable parts such as door handles and medical shelves in quasi-contaminated spaces, which are spaces between contaminated and non-contaminated spaces, but the corona-virus has not been identified in cases of out-of-touch walls. Implications: It is necessary to evaluate the performance by testing the construction finishing materials of infection control facilities according to domestic conditions.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.102-107
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• 2009

This study has been focused on an effective surface finishing method combining ELID (ELectrolytic In-process Dressing) and MAP (Magnetic Assisted Polishing) for the nano-precision mirror grinding of glass-lens molding mould. ELID grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials. A polishing process is also required for elimination of scratches present on ELID grinded surfaces. MAP has been used as polishing method due to its high polishing efficiency and superior surface quality. It also presents some techniques for achieving the nanometer roughness of the hard material such as WC-Co, which are extensively used in precision tooling material.

• 기계와재료
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• v.10 no.3 s.37
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• pp.71-77
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• 1998

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.176-181
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• 2007

This study aims to evaluate theoretically heat transfer characteristics and heat flux performance in ondol system of dried type is composed of panel of ceramics to improve of thermal conductivity and fin to expand heat. To this end, we analyzed effect of design factors(temperature of hot water, set temperature of room and thermal conductivity of finishing materials) in ondol system of dried type by heat transfer analysis. The main results of this study are summarized as follows; The deviation of heat flux and temperature was reduced by heat expansion from fin decreasing heat loss generated in air layer. The temperature and heat flux in upper finishing materials surface linearly increased according to temperature increment of hot water, but the temperature distribution in upper surface was assessed uneven. The greater heat resistance value of upper finishing materials, the deviation of maximum temperature and minimum temperature was decreased. Also, we suggested a basic design data about ondol system of dried type through an analysis of simulation results on heat transfer characteristics and heat flux performance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1768-1771
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• 2003

Hard turning replaces grinding for finishing process with expectations of higher productivity and demanded surface quality. Especially for the surface roughness as surface quality demanded in finishing process of hard turning, know-how of machining characteristics of hardened materials by cutting force analysis should be accumulated in company with achievement of precision of elements and high stiffness design technology in hard turning. Considering chip formation mechanism of hardened materials, adequate cutting conditions are selected for machining experiments and cutting forces are measured according to cutting conditions. Increase of cutting forces especially thrust force and increase of dynamic instability could occur in hard turning. Analysis of dynamic characteristics of the cutting forces is executed to investigate relation between dynamic instability and surface roughness in hard turning. Investigation on effects of relative motion of machining system generated by vibration due to dynamic instability shows that ultimate surface roughness could be predicted considering relative motion of machining system with geometrical surface roughness.

• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.64-72
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• 2012

Recently, prepackaged-type surface preparation materials using redispersible polymer powders are widely used for interior and exterior finishing in the construction work. The purpose of this study is to evaluate the performance and the quality of prepackaged-type surface preparation materials using a VA/E/MMA terpolymer powder. Surface preparation materials using a VA/E/MMA terpolymer powder were prepared with shrinkage reducing agent contents of 0, 4 % and cellulose fiber contents of 0, 0.5, 1.0 %, and tested for drying shrinkage, strengths, adhesion in tension, crack and impact resistance, water absorption, permeability. As a result, prepackaged-type surface preparation materials show outstanding performance depending on the shrinkage reducing agent and cellulose fiber contents.