• Journal of the Korean Wood Science and Technology
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• 제46권6호
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• pp.735-747
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• 2018

Radon radiation exposures in home have been posed as a potential cancer hazard. This research aims to present the basic data of the indoor radon concentration level by examining the radon exhalation rates of wood species. Radon exhalation rates from five commonly used wood species in Korean wood building construction were measured with Continuous Radon Monitor (CRM), Model 1028 (Sun Nuclear Co., USA) using the Closed Chamber Method (CCM). The mass exhalation rate was observed to vary from $0.00089Bq{\cdot}kg^{-1}{\cdot}h^{-1}$ to $0.00181Bq{\cdot}kg^{-1}{\cdot}h^{-1}$, whereas the surface exhalation rate was observed to be $0.00677-0.01517Bq{\cdot}m^{-2}{\cdot}h^{-1}$. The radon exhalation rate of Quercus accutissima Carruth (white oak) which has the highest density showed the highest figure among the five wood species, on the other hand, the rest of four species showed similar results which were similar to the radon exhalation rates of wood in the U.S.A. and Canada. The average of the concentration measured by the CCM represented well up to the second half-life period (7.7 days). Because result of these small quantities seems to indicate that radon exhalation from the tested wood species has almost negligible impact, the main culprit of the high indoor radon concentration is clearly derived from the background of surrounding wood house. Therefore, as a safety precaution, infrastructures made of wood materials should be designed with the consideration of influx of radon and built accordingly. Furthermore, it is highly desirable that wood will be needed to use for furniture and interior finishing material in indoor environment.

• 한국가구학회지
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• 제25권3호
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• pp.223-232
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• 2014

To make metalized wood composites of 10 different korean wood species, it was tested by Low temperature melting Bi-Sn alloy injection method at high temperature and high pressure condition. Metalized wood composite of each wood species had light ash color, but still maintained its own natural wood grain and wood figures. It was evaluated on coating properties. Furthermore, it also was check on effect of coating as like a changes of main color, wood grain and wood figures. The results of test were following as; a coating properties as like a cold resistance, heat resistance, acid resistance, alkali resistance, durability of abrasion, and cross-cut test was proper on the conditions of the KS standard. And, In aspect of color changes, the metalized wood composites of 10 different korean wood species had a light ash color, but still maintained its own natural wood grain and wood figures. Also, the more weight per gain of alloy is, the more grey background of metalized wood composite is.

• 한국가구학회지
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• 제11권2호
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• pp.25-35
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• 2000

This study was carried out to investigate the wood properties for development the proper uses of lesser-known tree species. The tested species are Tamiang(Hydnocarpus woodii) Bangelem (Strombosia zeylanica) and Kamasulan(Anisophyllea ferruginea) grown in Indonesia. fundamental wood properties such as anatomical, physical and chemical properties and characteristics related to wood processing were examined. The results are summarized as follows : These species are diffuse porous, interlocked grained and coarse textured wood. Exceptionally, texture of Tamiang is fine. The heartwoods of these species are not distinguished clearly to the sapwoods. These species have high specific gravity, high shrinkage, and excellent strength properties. However, Tamiang has moderate specific gravity. Sawing characteristics are poor for these species except Tamiang. Sawing characteristics is moderate for Tamiang. Drying characteristics are moderate for Tamiang and Bangelem, and Poor for Kamasulan. The surfacing characteristics by planer are moderate f3r all these species. Bending property and durability are poor. Ash content is low in Bangelem.

• 한국가구학회지
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• 제11권1호
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• pp.13-23
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• 2000

This study was carried out to investigate the wood properties for development the proper uses of lesser-known tree species. The tested species are Kebambang(Pentace sp.), Bawang-bawang(Dysoxylum alliaceum Bl .), Garu buaya( Gonystylus brunescens A. Shaw)grown in Indonesia. fundamental wood properties such as anatomical, physical, mechanical and chemical properties and characteristics related to wood processing were examined. The results are summarized as follows : The woods of these species are diffuse porous, coarse textured, and interlocked grained. The heartwood of Kebambang is distinguished clearly to the sapwood, but the heartwood of other species are not distinguished clearly to the softwood. The woods of Kebambang and Bawang-bawang have the moderate weight density and the low strength properties, but Garu buaya has the high weight density and the high strength properties. The woods of these species has high shrinkage. The sawing characteristics of Kebambang are excellent but the other species are moderate. The machining characteristics by planer and drying characteristics of these species are moderate. These woods has poor characteristics in bending processing and decay durability. The wood of Bawang-bawang has high content of the extractives and lignin.

• 한국가구학회지
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• 제13권2호
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• pp.19-28
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• 2002

This study was carried out to investigate the wood properties for efficient utilization of warm temperate tree species. The tested species were Actinodaphne lancifolia Meisn. grown in Korea. Fundamental wood properties such as anatomical, physical and mechanical properties and chemical components were examined. This species was diffuse porous, straight grained and fine textured wood. The heartwoods of this species was not distinguished clearly to the sapwoods. This species had moderate specific gravity, shrinkage, and mechanical properties. And this species had high content of the extractives by organic solvent.

• Journal of the Korean Wood Science and Technology
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• 제44권6호
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• pp.897-902
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• 2016

This study was conducted to identify wood species from main pillars of Daeungjeon Hall, the main building of Jeonghyesa Temple located in Suncheon, Jeollanamdo Province in Korea. It was known that this temple had been built in the $8^{th}$ century by Hyeso, a national master in the Unified Silla period, and was designated as Treasure No. 804 in 1984 due to its historic and academic values. The results of wood species identification showed that main pillars from Daeungjeon Hall of the Jeonghyesa Temple were made of hard pine, Korean fir (Abies spp.) and Zelkova tree (Zelkova spp.). In addition to the wood species identification, floor plan documentation was also done to help identify what wood species had been used for main pillars. These results could be applied and utilized for the conservation and restoration of Daeungjeon Hall in future. This study may help with the authenticity of conservation works.

• Journal of the Korean Wood Science and Technology
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• 제49권6호
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• pp.574-590
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• 2021

전 세계적으로 불법목재 방지를 위한 국제적 노력이 확대되고 있으며, 우리나라는 국내에 수입·유통되는 목재의 합법성을 강화하기 위하여 2019년 '합법목재 교역촉진제도'를 시행하고 있다. 합법목재 교역촉진제도는 목재, 목재제품 등을 수입할 시 생산 국가, 수종, 벌채지 등에 대해 합법한 목재임을 입증하는 제도이다. 입증 방법에는 주로 DNA 분석 기술과 현미경을 이용한 해부학적 특징 분석이 함께 이용되고 있다. 따라서, 본 연구에서는 다양한 목재제품 중에 우선적으로 합판의 해부학적 특성을 분석하여 수종 식별을 하였다. 공시재료는 합판 생산 기업의 합판(7, 9ply)을 취급하는 4업체를 선정하여 미송(Pseudotsuga menziesii (Mirb.) Franco.) 및 낙엽송(Larix kaempferi (Lamb.) Carriere)합판을 구입하여 시료를 확보하였다. 각 회사의 합판을 약 1cm³ 크기로 절삭한 뒤, 표판부터 이판까지 하나의 단판으로 분리하여 광학현미경을 이용하여 3단면을 관찰하였다. 수종식별 결과, 침·활엽수 혼합 합판과 소나무류, 포플러류, 낙엽송·소나무류의 혼합으로 구성되어 있었다. 현미경법을 이용한 목재의 수종식별은 무분별한 불법 목재의 유통 및 불법 벌채 위험국가로부터 수입되는 합판을 비롯한 다른 여러 가지 목재 제품을 과학적으로 분석·검증할 수 있는 중요한 분야이다

• Journal of the Korean Wood Science and Technology
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• 제32권6호
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• pp.57-66
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• 2004

To study the efficient usage of small diameter logs and woods containing defects such as knots, slope of the grain and decay, six types of finger-jointed woods with various finger profiles were made of poplar, pine and oak with different density. We investigated the effect of finger profile on static bending strength performances of finger-jointed woods. The efficiency of bending MOE, MOR and deflection showed the highest value in poplar finger-jointed wood with the lowest density of three species, and the lowest value in oak finger-jointed wood with the highest density of three species. The values markedly decreased with increasing finger pitch for finger-jointed wood glued with polyvinyl acetate (PVAc) resin for all tested species, whereas for the finger-jointed wood glued with resorcinol-phenol formaldehyde (RPF) resin, the influence of finger pitch on the efficiency of MOE was not found in all tested species, and those on the efficiency of MOR and deflection indicated the same trend as finger-jointed wood glued with PVAc resin in the case of pine and oak finger-jointed wood with higher densities. It was found that the values tended to decrease with increasing density of species on the whole and the desirable finger pitches were L (6.8 mm) for poplar, M (4.4 mm) for pine and S (3.5 mm) for oak in a view of economy. For finger-jointed wood glued with PVAc resin, the fitness between a tip and a root width of a pair of fingers δ of 0.5 mm indicated the highest efficiency of MOE for all species. And, the influence of δ on MOR was only found in oak finger-jointed wood glued with RPF resin and the desirable δ value for oak was 0.1 mm. However, it was found that the influence of δ on the strength performance was very small.

• Mycobiology
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• 제44권4호
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• pp.217-236
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• 2016

Polyporoid and corticioid fungi are among the most important wood-decay fungi. Not only do they contribute to nutrient cycling by decomposing wood debris, but they are also valuable sources for natural products. Polyporoid and corticioid wood-inhabiting fungi were investigated in Odaesan National Park. Fruit bodies were collected and identified based on morphological and molecular analyses using 28S and internal transcribed spacer regions of DNA sequences. As a result, a total of 149 species, 69 genera, 22 families, and 11 orders were recognized. Half (74 species) of the species were polypores, and the other half (75 species) were corticioid fungi. Most of the species belonged to Polyporales (92 species) followed by Hymenochaetales (33 species) and Russulales (11 species). At the genus level, a high number of species was observed from Steccherinum, Hyphodontia, Phanerochaete, Postia, and Trametes. Concerning distribution, almost all the species could be found below 1,000 m, and only 20% of the species were observed from above 1,000 m. Stereum subtomentosum, Trametes versicolor, T. hirsuta, T. pubescens, Bjerkandera adusta, and Ganoderma applanatum had wide distribution areas. Deciduous wood was the preferred substrate for the collected species. Sixty-three species were new to this region, and 21 species were new to Korea, of which 17 species were described and illustrated.

• Journal of the Korean Wood Science and Technology
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• 제16권1호
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• pp.9-20
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• 1988

Lespedeza species have been widely used not only as plant resources for bark, leaves and honey, but also as erosion control materials. This study was carried out to investigate the structural and wood tiber characteristics in order to obtain basic information for the utilization of the wood. The wood structure was investigated for 10 selected species and the wood fiber, for the 5 selected species among Lespedeza species distributed all over the country. The following results were obtained. In the cross section, campylotropis showed ray diffuse porous wood, L. bicolor, L. cyrtobotrya, L. thunbergii var. intermedia, diffuse porous wood, and L. tomentella, L. angustifolioides. L. maritima, L. robusta, L. patentibicolor, ring porous wood. The maximum diameter of a single vessel ranged 66-123 ${\mu}$ in all species. Campylotropis showed the most number of vessels, L. angustifolioides, the least. The number of ray per mm ranged 7-22, Campylotropis showed the most number of rays, L. angustifolioides, the least. In the radial section the average length of vessel ranged 121-250 ${\mu}$ in all species. L. thunbergii var. intermedia showed the longest vessel, L. tomentella, the shortest. In tangential section the average width of the uniseriate ray ranged 9.2-14.7${\mu}$, that of the multiseriate ray, 19.2-42.1 ${\mu}$. The average height of the uniseriate ray ranged 143.0-1162.0 ${\mu}$. The width of fiber ranged 10.12-13.61 ${\mu}$, L. maximowiezii showed the narrowest tiber, L. thunbergii var. intermedia. the widest, the thickness of fiber wall ranged 2.93-3.71 ${\mu}$ in the five species. L. maximowiezii showed the most thin fiber wall, L. thunbergii var. intermedia, the thickest, L. cyrtobotrya showed the difference in the size of fiber between the shade and the sunny sites but L. maximowiezii showed no difference. There was significant difference in fiber length, fiber width and wall thickness between L. eyrtobotrya and L. maximowiezii.