• Journal of the Korean Wood Science and Technology
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• v.41 no.1
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• pp.58-63
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• 2013

This study is a basic research for practical applications of carbonized boards, which measured thermal conductivity and electrical properties of carbonized boards manufactured at different carbonization temperature ($400{\sim}1,100^{\circ}C$) using a medium density fiberboard, particleboard, plywood and wood (Fraxinus rhynchophylla). The highest value of thermal conductivity was 0.1326 m/k at carbonization temperature of $900^{\circ}C$ in the carbonized particleboard. Overall, the higher density of carbonized board, thermal conductivity was faster. As the electrical resistivity decreased with increased carbonization temperature, it was almost close to conductor after carbonization temperature of $1,000^{\circ}C$. When electricity has worked on the carbonized board by high voltage, the current and the electric power increased and surface temperature of carbonized board was high.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.60-66
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• 2018

For new use development of carbonized board, we investigated the effect of carbonization temperature on the surface temperature of carbonized board manufactured from a plywood, particle board, MDF, and wood of Fraxinus rhynchophylla at different carbonization temperature ($400^{\circ}C{\sim}1100^{\circ}C$). The surface temperature of carbonized board precipitously increased until 12 minutes elapsed, after smoothly increased and thereafter which were stable after 20 minutes. The higher carbonization temperature increased density of carbonized board and surface temperature of carbonized board so that density is considered to influence surface temperature change. Moreover, carbonized boards kept heat for a long time because the descent velocity of carbonized boards' surface temperature was slower than that of heater's.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.746-752
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• 2017

Cross-laminated timber (CLT) is a relatively new engineered wood for timber construction. It is a great shear wall material. It was known that the shear performance of the CLT wall depends on the performance of connections. In connection, nail or screw has to be installed with a certain distance from the end of the timber. Current building code specifies the distance on the name of end distance. The end distance was decided as a minimum distance not to make splitting or tearing out in lumber or glued laminated timber. As a relatively new engineered wood, the end distance of CLT connection need to be identified because CLT is cross-wisely glued lumber products like plywood. Different from glued laminated timber or lumber, cross layer of CLT may prevent wood from splitting or tearing-out. As a result, the end distance of CLT was expected to be reduced than glued laminated timber. The shorter end distance may let more versatile connector design possible. In this study, prior to developing novel connection for CLT, the end distance of CLT connection was experimentally investigated to identify the end distance limitation. The experiments showed that the end distance can be reduced from 7D to 6D, in case of the tested CLT combination and screw in this study.

• Journal of the Korean Society of Costume
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• v.29
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• pp.23-38
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• 1996

The purpose of this study was to analyze the characteristics of the Minimal Art represented in the second half 20th century fashion. All the mode of dress worn this century have developed from the stimulus of a chang-ing society fired by new discoveries and a zest for the new and different. It would appear that even more dramatic changes will soon occur in our clothing styles the effects of which will be farreaching. Many of today's styles intended to dress our psyche rather than our bodies and this if fully understood by the new designers whose influ-ence will become increasingly more potent as we approach the new century. The highly developed material civilization resulted in human alienations environmental distruption, l By this fact human being of the 20th century was to overcome social com-plexity. Accordingly their search for simplicity was interested in the 60's style. Especially the formativeness of the 60s style was repre-sented in the second half 20th century fashion. In this paper it was focused that how the characteristics of the Minimal Art was expressed in the second half 20th century fashion. minimalism was a quest for basic elements repesenting the fundamental esthetic values of art. without regard to issues of content. At its most extreme it reduced art not ot an eter-nal essence but to an arid simplicity. "Primary Structure" the most suitable name suggested for this type conveys its two salient characteristics : extreme simplicity of shapes and a kinship with architecture. minimalist works are charcterized by huge dimensions coldness and absolute aesthetic neutrality. minimalist artists ambition is to de-fine through the most rudimentary materials such as plywood galvanized iron aluminum plastic and wood a new order of the space. The environment is just as important as the object itself. Similary the use of new tough materials. such as vinyl metal and plastic at late half of the 20th century fashion related to the formativeness of the Minimal Art. And the style of 20th fashion was holded the internal meanings in common the formativeness of the Minimal Aet thorough the various texture pat-tern silhouette etc.uette etc.

• Journal of Preventive Medicine and Public Health
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• v.24 no.3 s.35
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• pp.314-327
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• 1991

To evaluate the effects on health by exposure to mixed organic solvents, the author analyzed some labortory findings of blood (hemoglobin, hematocrit RBC, WBC, SGOT, SGPT) and urine (protein, blood, sugar) that were obtained from 722 workers (male:446, female:276) who worked in plywood, painting and shoes factories in Pusan area from January to December, 1990. The result were as follows ; 1. The mean values of each hematologic findings were all within normal limit but there were significant differences at hematocrit, RBC, WBC, SGOT in male and at WBC, SGPT in female at the comparison of the mean values and the distribution according to the normal criteria by type of work. 2. There were no differences in urinalysis(protein, blood, sugar) by type of work. 3. In stepwise multiple regression, analysis of hematologic findings on age, working duration and type of work, regression coefficients on age and type of work were relatively high in male and female sub1, respectively. As a result of this study, it is considered that the measurement of WBC with morphology is significant in hematologic findings and instead of spot urine and urinstix, 24 hours urine and quantitative analysis is required in urinalysis in screening test for healthy status of workers who deal with the organic solvents.

• Journal of Adhesion and Interface
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• v.9 no.2
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• pp.32-37
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• 2008

A series of UV-curable powder coatings with different contents of photoinitiator (0.5 wt%, 1 wt%, 2 wt%) were formulated and measured gel content, tensile strength of cured film. Heat-sensitive substrates such as MDF, plywood and PVC were coated UV-curable powder and cured coatings were measured physical properties by pendulum hardness tester, glossmeter, pull-off adhesion tester. With increasing photoinitiator content, adhesion force between coating and substrate decreased because of crosslinking density increasing. The results of pendulum hardness was not significantly changed but gloss was changed according to different substrates. Adhesion of UV-curable coatings was enough to apply for heat-sensitive substrates. From these results, we concluded that contents of photoinitiator was a effective factor in UV-curable powder coatings. UV-curable coatings was a portential candidate for heat-sensitive substrates.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.297-305
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• 2016

This study aims to analyze characteristics of environmental load for the construction phase of PSC beam bridge based on Life Cycle Assessment. For detail computation of environmental load, the construction materials and energy consumption are derived from the BOQ, also connecting with environmental load by Korea LCI Database Information Network. The characteristic of environmental impact was analyzed by 25 cases and cut-off ratio was 80% to 94%. The result sorted by construction materials revealed that environmental load were 53.3% for ready-mixed concrete, 9.6% for wire rod, 7.8% for rebar, 6.8% for cement, 5.5% for plywood, and 5.2% for energy. Furthermore, the result of environmental impact revealed that 45.5% for global warming, 30.4% for abiotic resources depletion, 10.5% for human toxicity, and 8.9% for photochemical oxidant creation. In the future, we can make a decision considering environmental load based on LCA at design phase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6959-6968
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• 2015

This study aims to update the supply-demand model of wood products(FOSMO-2013) and to forecast mid and long run supply and demand for each products. The subjects of the study include sawnwood, plywood, particle board, fiberboard(MDF), and pulp. The updated partial equilibrium model is composed of supply function, import demand function, demand function, price relation function. The long run outlooks of world prices of wood and wood products are imported from the results of Buongiorno(2012). This study also adopt Buongiorno's scenarios, which includes three scenarios of IPCC(A1B, A2, B2) and the other one with assumption of increasing fuelwood consumption of A1B scenario. The result says that the domestic productions of wood products are expecting to decrease while the imports of them increase even there are some differences among the products as well as scenarios.

• Journal of the Korea Furniture Society
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• v.21 no.3
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• pp.237-247
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• 2010

This research was carried out to examine the properties of black charcoal board, in order to find the proper manufacturing condition for the black charcoal-board made of the charcoal. The charcoal in this study was distillated from domestic wood waste, and it were also the purpose of this study to see if the black charcoal-board has the advantageous properties of charcoal as a well-being building material against the sick house problem. Domestic wood waste was consisted of MDF 40%, PB 30%, plywood 15% and wood 15%, respectively. Black charcoal board was produced by hot pressing with following conditions; temperature $170^{\circ}C$, three stage pressing cycle of $40-10-40\;kgf/cm^2$(1min.-2.5min.-5min.) and non formaldehyde adhesives [P15%+M5%:MDI(M), poly vinyl acetate emulsion(P). Fine mixed particle size [#6-12(16.9%), #12-18(16.7%), #12-40(47.2%), #40-60(9.5%), #60-100(5.9%), less than #100(3.8%)] gave better results than larger particle size [over #6(33.8%), #12-18(17.7%), #12-40(37.7%), #40-60(6.4%), #60-100(2.6%), less than #100(1.8%)]. Final moisture content of the mat was best at 36%. Black charcoal-board showed less MOR and IB(internal bond), more WA(water absorption) than that of white charcoal-board. Black charcoal board showed not only the same gas adsorption and dimensional stability as white charcoal board but also good cutting, nailing and drilling for indoor environment systems.

• Journal of the Korean Wood Science and Technology
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• v.11 no.3
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• pp.31-38
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• 1983

This experiment was carried out to improve the physical and mechanical properties of sawdust-board by combining with reinforce material, that is, plastic wire screen and steel wire screen. In experiment results, the density of sawdust-board reinforced with three steel wire screens was highest and its bending strength was also highest. Wastepaper-5% mixed sawdust-board showed as high bending strength as other boards, and therefore the possibility of using wastepaper as raw materials for boards. The sawdust-board with steel wire screen was not ruptured immediatedly after having been deformed by static loading. However, plywood showed higher bending strength than the reinforced sawdust-boards.