• Journal of the Korean Wood Science and Technology
• /
• v.21 no.1
• /
• pp.15-20
• /
• 1993

X-ray diffractograms of the vessel elements and the wood fibers of Quercus variabilis BLUME were recorded and resolved into characteristic reflections of cellulose I. Some differences were observed in the ratio of integrated intensity and crystallinity index between vessel elements and wood fibers. Present results suggest that cellulose crystal structure in the hardwood species was varied with the elements of wood.

• Korean Journal of Agricultural Science
• /
• v.37 no.3
• /
• pp.465-469
• /
• 2010

In order to develop effective recycling technologies of disused railway wood ties, wood properties and residual creosote oil of wood ties were investigated. Among the total 50 wood ties, 32 wood ties were identified as tropical hardwood tree, such as, Keruing (Dipterocarpus spp.), Kempas (Koompassia malaccensis), Kapur (Dryobalanops spp.) Naytoh (Palaquium rostratum), and so on. Disused wood ties showed mostly sound structure without degradation of cell walls by decay fungi. Disused wood ties showed high strengths of bending and compressive parallel to grain because degradation of wood properties was hardly occurred in use under exterior condition. Disused railway wood ties had relatively poor depth of penetration and residual of creosote oil because of refractory wood structures. These results suggest that disused railway wood ties may be useful as recycling wood wastes.

• Journal of the Korean Wood Science and Technology
• /
• v.6 no.1
• /
• pp.15-23
• /
• 1978

This report observed for anatomical structure and identified species of small wood debris collected at Chungi-Hyankyo, Yunbuk-Chung, Jeju-Hyankyo, Teachung-Hyangkyo and Kwanduk-Chung in Jeju province constructed in a central period of Yi-dynasty, and now named as local cultral assets. 1. Sample of Chungi-Hyangkyo is gymnosperm with window-like pit, axial and radial cannal & dentate ray tracheid. This sample with identified with Pinus densiflora or Pinus thunbergii. 2. Samples of Yunbuk-Chung and Jeju-Hyangkyo are diffuse porous wood having small vessels with scalariform perforation plates scattered almost equally in annual ring, possess heterogenus ray parenchyma & banded apotracheal parenchyma. This sample is identified with Distylium racemosum. 3. Sample of Teachung-Hyangkyo is ring porous wood composed of big vessels of pore zone and compound vessels outside pore zone. It also has simple perforation plates, tylosis, homogenlls uniseriate ray parenchyma & diffuse parenchyma This sample is identified with Castanopsis cuspidata. 4. Sample of kwanduk-Chung is ring porous wood composed of big vessels of pore zone and compound vessels outside pore zone. It has simple perforation plates, heterogenus ray parenchyma, crystal, vasicentric parenchyma. This sample is identified with Zelkova serrata.

• Journal of the Korea Furniture Society
• /
• v.17 no.3
• /
• pp.17-21
• /
• 2006

An investigation was done to know the warty layer structural difference in bordered pit of longitudinal tracheid in Pinus densiflora Sieb. et Zucc., Pinus koraiensis Sieb. et Zucc., Pinus rigida Mill. and Larix kaempferi Carr. grown in Korea. Among the four wood species, warty layer was found in bordered pit of longitudinal tracheid of Pinus densiflora Sieb. et Zucc. and Pinus rigida Mill. The mean height and horizontal diameter of warty layer was found highest in Pinus densiflora Sieb. et Zucc. The height of warty layer was found the highest in juvenile wood of Pinus densiflora Sieb. et Zucc. and it gradually decreased towards the matured wood.

• Journal of the Korean Wood Science and Technology
• /
• v.32 no.3
• /
• pp.66-70
• /
• 2004

The antioxidant activities of six isoflavonoids isolated from Sophora japonica wood and bark were examined by DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging method. This study was focused on the relationship between antioxidant activity of isoflavonoids and their chemical structures. From the results of this study, it could be concluded that the hydroxyl groups that linked at ring B and ring A in isoflavonoids have importance in the antioxidant activity. Additionally, the absence of the 2,3-double bond on the isoflavonoid enhances its antioxidant activity.

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

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.2
• /
• pp.123-133
• /
• 2013

This paper presents experimental and numerical tests on a recently developed timber column concealed base joint. This joint was designed to replace the wood-wood connection found in the post-and-beam structure of Hanok, the traditional Korean timber house. The use of metallic connectors provides an increased ductility and energy dissipation for a better performance under reversed loading, especially seismic. In this study, we investigate the performance of the joint under pseudo-static reversed cyclic moment loading through the study of its ductility and energy dissipation. We first perform experimental tests. Results show that the failure occurs in the metallic connector itself because of stress concentrations, while no brittle fracture of wood occur. Subsequent numerical simulations using a refined finite element model confirm these conclusions. Then, using a practical modification of the joint configuration with limited visual impact, we improve the ductility and energy dissipation of the joint while retaining a same level of rotational strength as the originally designed configuration. We conclude that the joint has a satisfying behavior under reversed moment loading for use in earthquake resistant timber structure in low to moderate seismicity areas like Korea.

• Proceedings of the KSFDT Conference
• /
• 2006.04a
• /
• pp.93-98
• /
• 2006

• Proceedings of the KSFDT Conference
• /
• 2006.04a
• /
• pp.183-186
• /
• 2006

• Journal of the Korean Wood Science and Technology
• /
• v.10 no.4
• /
• pp.1-10
• /
• 1982