• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.58-67
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• 2010

Combustion of the Korean Anthracite and wood-pellet was characterized in air atmosphere with variation of heating rate(5, 10, 20 and $30^{\circ}C/min$) in TGA. The results of TGA have shown that the combustion of the wood-pellet occurred in the temperature range of $200{\sim}620^{\circ}C$ which is much lower than that of Korean anthracite. Activation energies of the wood-pellet and Korean anthracite, determined by using Friedman method were 44.12, 21.45 kcal/mol respectively. Also, their reaction orders(n) and pre-exponential factors(A) were 5.153, 0.7453 and $4.01{\times}10^{16}$, $1.39{\times}10^6(s^{-1})$ respectively. In order to find out the combustion mechanism of the wood-pellet and Korean anthracite, twelve solidstate mechanisms defined by Coats Redfern Method were tested. The solid state combustion mechanisms of the woodpellet and Korean anthracite were found to be sigmoidal curve A3 type and a deceleration curve F1 type respectively. Also, from iso-thermal combustion($300{\sim}900^{\circ}C$) of their char, the combustion characteristics of their char was found. Activation energies of the their char were 27.5, 51.2 kcal/mol respectively. Also, pre-exponential factors(A) were $2.55{\times}10^{12}$, $1.49{\times}10^{10}(s^{-1})$ respectively. Due to the high combustion reactivity of wood-pellet compared with Korean anthracite, combustion atmosphere will be improved by co-combustion with Korean anthracite and wood-pellet.

• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.16-19
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• 2010

Devolatilization characteristics of municipal wood waste were measured by using an isothermal thermogravimetric analyzer(TGA) and discussed. Volatile matter was mainly released at temperatures between $250^{\circ}C$ and $350^{\circ}C$. The volatile content increased with an increase of temperature but levelled off at temperatures ${\geq}527^{\circ}C$. The rate of devolatilization could be expressed by a shrinking particle model which was ruled by the reaction rate. The activation energy ranged from 13.1 to 18.5 kJ/g mol.

• Korea Trade Review
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• v.47 no.5
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• pp.147-160
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• 2022

This study aim to use the GTAP model to analyze the impact of RCEP Fermentation in the Korean manufacturing industry by quantifying the RCEP tariff commitment table. The research results show RCEP has boosted output in all sub-manufactures except wood and printed matter due to increased export volumes. Wood products, on the other hand, are more reliant on imports due to lower production due to lower domestic sales or overall exports. After RCEP came into effect, the import and export scale of Korea's manufacturing industry expanded effectively. Among them, the positive impact on the intensive low-tech manufacturing industries such as clothing and leather products, wood products and printing products, and food, beverage and tobacco products is greater than the positive impact on the technology-intensive medium and high-tech and high-tech manufacturing industries. And found that the growth rate of Korea's manufacturing trade is basically proportional to the tax reduction rate of RCEP. Finally, in order to promote the development of the manufacturing industry, some suggestions are put forward that need the government's policy support and strengthen the regional cooperation with RCEP member countries.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.283-293
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• 2016

Owing to an increase in the air tightness of recent buildings, the natural ventilation rate was significantly lowered and the removal of accumulated moisture became difficult in these buildings. The hygrothermal performance of these buildings should be carefully considered to provide comfortable indoor environment by removing the moisture condensation risk and the mold growth potential. In this study, hygrothermal performance of two selected wall structures was investigated based on WUFI simulation program. The results displayed that the indoor temperature had impact on the moisture accumulation in the insulation layer for both modeled walls, showing that lower indoor temperature resulted in higher moisture accumulation, especially in the wood frame structure. Also, the yearly moisture accumulation profile exhibited a downward shift throughout the year by adding a vapour retarder with a lower sd-value. In addition, both of the two walls have condensation risk in winter, due to low temperature level. The wood frame structure has a bigger fluctuation and higher condensation risk than the concrete structure.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.144-147
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• 2008

Inonotus obliquus could be isolated from Betula platyphylla var. japonica with diameter in the range of 6$\sim$13 cm that artificially inoculated by the fungus. The diameter and/or inoculation point of tree did not show any significant relationships with the infection rate of the fungus. Inonotus obliquus showed rapid growth on vertical direction of the infected tree while the growth was quite low on radial direction. The isolated fungus from the infected tree did not show vegetative incompatibility with the original fungus used for inoculation. We could isolate 8 contaminants from the inoculated area; Trichoderma reesei, T. atroviride, Cryptococcus neoformans, Botrytis cinerea, Fusarium sp. and 3 unknown species.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.440-448
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• 2016

As recent buildings become more air tight, the natural ventilation rate is significantly reduced and it leads to difficulty in removing accumulated moisture in buildings. Hot and humid weather in summer and the large amount of moisture caused by indoor activity are the major factors of moisture problem in Korea. The hygrothermal behavior of building environment has to be considered carefully to reduce condensation risk and mold growth potential, and comfortable indoor environment. In this study, we evaluated hygrothermal behavior of Standard Wood-frame Structure published in the Korea Rural Community Corporation Using WUFI simulation program. The results indicated that the total water contents of wood wall measured in 2014 was lower than wood wall in 2010. As a result of evaluation by separating the farming and fishing areas, Moisture problems in fishing area became larger. The walls had a significant impact on the relative humidity than the temperature each areas. Furthermore, excessive water content problem of the wood-based material was reduced in the wall that could be applied in the fishing villages by changing the outdoor finishing materials. And Mold growth risk on the interior materials could be removed through the different setting of the indoor temperature during summertime.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.6
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• pp.381-388
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• 2000

The temperature and velocity fluctuations occurred by the baroclinic instability in the melt for Czochralski crystal growth method were experimentally investigated. Wood's metal, which has similar Pr number to the silicon melt, was used as the working fluid and azimuthal velocity was measured using incorporated magnet probe. The azimuthal velocities near the free surface are faster than velocities near the bottom and the rotational velocities near the model crystal become very fast. The results of measured temperature fluctuation as increasing rotation rate were shown that baroclinic instability occurred at the region of Ro<1.01, Ta>$9.63{\times}10^8$. In these region, the fluctuations of temperature and velocity have the same frequency.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.579-586
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• 2010

This study was carried out to evaluate the antifungal and antioxidative activities of ethanol extracts from Magnoliaceae to investigate the possibility for the natural fungicides and food preservatives. The antifungal activities of ethanol extracts were evaluated as a hyphal growth inhibition rate using four plant pathogenic and five wood rot fungi. The high inhibition activity on the growth of fungi was shown in bark of Magnolia obovata that indicated more than 50% hyphal growth inhibition rate except Trametes versicolor, one of the white rot fungi. The antifungal activity was the highest in the ethanol extracts from M. obovata and the following was in order of M. kobus and M. sieboldii. The extract from bark in M. obovata showed higher antifungal activity than that from wood in the same species. Especially, the extracts from flower of M. denudata and M. liliflora indicated the high antifungal activities, while the other portions of same plants showed the low activities. On the other hand, a free radical scavenging method was adopted with 1,1-diphenyl-2-picrylhydrohydrazyl (DPPH) in order to test the antioxidative activities of ethanol extracts. The free radical scavenging activity was very high in the extracts from branch of Schizandra nigra and Kadsura japonica that showed more than 90% at the concentration of 100 ${\mu}g/m{\ell}$. It also turned out that the antioxidative activity of branch of S. nigra and K. japonica was similar to ${\alpha}$-tocopherol and butylated hydroxytoluene, one of the effective synthetic antioxidants. From these results, it can be suggested that the branches of S. nigra and K. japonica have the positive antioxidative activities and can be applied for the food preservatives and cosmetic ingredient.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.28-32
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• 2007

Fruiting bodies of Inonotus obliquus were collected from the trunk of Betula ermani at 1,100 m of Mt. Odae. Diameter range of the trees at breast height (DBH) was $10{\sim}50$ cm and size range of the sclerotia was $8{\times}5{\sim}20{\times}16cm$. Relationships between the examined strains and Inonotus obliquus strain registered in National Center for Biotechnology Information (NCBI) were very near. And all of 10 strains except strains registered in NCBI showed high homologous characteristics by neighbour joining analysis of ITS sequence. Mycelial growth showed a big difference among strains. Mycelial growth of KFRI 744 was fastest and KFRI 739 was slowest. Difference of mycelial growth between KFRI 735 and 738 was slight, but the difference of mycelial growth between KFRI 744 and 739 was almost twice. Also weight reduction rate among strains showed some difference. KFRI 744 was highest and KFRI 741 was lowest. Vegetative incompatibilities were observed in all mycelial pairings except for KFRI 740-741 and KFRI 742-743 combinations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.4
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• pp.248-252
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• 2008

A 6-week feeding trial was conducted to investigate effects of dietary supplementation with wood vinegar (WV) as a feed additive for juvenile olive flounder, Paralichthys olivaceus. Eight experimental diets supplemented with 0(control), 0.01, 0.025, 0.05, 0.1, 0.25, 0.5 and 2.0% WV/kg diet($WV_0,\;WV_{0.01},\;WV_{0.025},\;WV_{0.05},\;WV_{0.1},\;WV_{0.25},\;WV_{0.5},\;and\;WV_{2.0}$, respectively) were prepared by mixing with basal diet. After the 6-week feeding trial, fish fed the $WV_{0.1}$ diet had significantly higher weight gain, feed efficiency, and specific growth rate than those of fish fed the other diets(P<0.05). No mortality was observed in the treatment groups fed the experimental diets for 6 weeks. The liver antioxidant activity of fish fed the $WV_{0.01},\;WV_{0.025},\;and\;WV_{0.05}$ diets was significantly higher than that of fish fed the other diets. The lysozyme activity of fish fed the $WV_{0.25}$ diet was significantly higher than that of fish fed the other diets. Fish fed diets supplemented with WV had significantly lower cumulative mortality than that of fish fed the control diet throughout the challenge test, and fish fed the $WV_{0.05}\;and\;WV_{0.1}$ diets had the highest resistance to disease caused by Edwardsiella tarda at day 7 of the challenge test. Therefore, feeding 0.05-0.1% WV/kg diet improves the growth and immune responses of juvenile olive flounder, Paralichthys olivaceus.