• Journal of the Korean Wood Science and Technology
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• v.14 no.2
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• pp.36-42
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• 1986

Both the control and heated specimen of oak, hornbean, alder, poplar, red pine and pitch pine among domestic commercial species and taun imported were used for radial and tangential shrinkage and movement that occurred on changing the relative humidity of the atmosphere from 90 percent to 60 percent at $25^{\circ}C$. The results of this study were as follows. 1. The radial and tangential shrinkage of the control and heated hornbean and oak wood, except alder, of high specific gravity showed greater than species with low specific gravity. The ratio of tangential to radial shrinkage was 1.46 for taun to 2.70 for alder. Green volume specific gravity of the heated and soaked specimen of all species except poplar decreased 1.5 to 3.1 percent. Shrinkage of the heated specimen increased more than that of the control specimen, and antishrink efficiency of all timbers except alder had negative value. Shrinkage from green to air dry of treated specimens increased more than case of total shrinkage, and radial shrinkage of those specimen increased greater than tangential shrinkage. 3. The movement of the heating specimen for 120 hours decreased than those of the control and the heating specimen for 240 hours. The movement of heating oak, poplar, red pine and pitch pine (or 240 hours increased rather than those of the control specimen.

• Journal of the Korean Wood Science and Technology
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• v.20 no.4
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• pp.43-48
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• 1992

A database system for retrieving the information on wood collections was developed using the D-BASE III Plus program for personal computers. Basic information of biological, physical, chemical and technological properties was added to the data which used to be employed in simple card systems, such as identification number, species name and collection site. All information was fast and reliably retrievable. This paper also discussed the results of a survey on wood collections housed at domestic colleges and research institutes.

• Journal of the Korean Wood Science and Technology
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• v.44 no.1
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• pp.48-56
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• 2016

In this study, to develop the lattice materials with a low environmental load for restoring the destroyed forest, 7 types of wood-concrete hybrid laminated materials were manufactured with domestic four softwoods, three hardwoods and concrete, and the effects of density of wood species on static bending strength performances were investigated. Bending MOEs of wood-concrete hybrid laminated materials increased with increasing density of wood species on the whole, and the values were higher than that of concrete by hybrid-laminating woods on the concrete. It was found that the measure values of bending MOEs were slightly lower than the calculated values calculated using equivalent cross-section method from MOE of each laminae of hybrid laminated materials and the difference between them was less than 10%. Bending proportional limit stresses of hybrid laminated materials showed 1.2-1.6 times higher than that of concrete by hybrid-laminating. Bending strength (MOR) of hybrid laminated materials increased with the density of wood species. By hybrid-laminating, the MOR of concrete was considerably increased. Therefore, it is considered that wood-concrete hybrid laminated materials can be applied as a materials with a low environmental load and durability for ecological restoration.

• Journal of the Korean Wood Science and Technology
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• v.51 no.5
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• pp.419-430
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• 2023

In this study, the floor impact sound insulation performance of Korean domestic Cross-Laminated Timber (CLT) slabs was evaluated according to their joint types, species and thicknesses in laboratory experiments. The sound insulation performance of the CLT has not been investigated before, thus, this study was conducted to quantify basic data on floor impact sound insulation performance of CLT slabs. 5-ply and 150 mm thick CLT panels made of 2 species, Larix kaempferi and Pinus densiflora, were used for the study. The CLT panels were assembled by 3 types of inter-panel joints to form floor slabs: spline, butt and half-lap. And the 150 mm thick Larix CLT slabs were stacked to the thicknesses of 300 mm and 450 mm. The heavy-weight floor impact sound insulation performance of the 150 mm CLT slabs were evaluated to be 70 dB for the Larix slabs and 71.6 dB for the Pinus slabs, and the light-weight floor impact sound insulation performance, 78.3 dB and 79.6 dB, respectively. No significant difference in the sound insulation performance was found between the slabs of the 2 species or among the 3 types of joints. The reduction of 1 dB in the heavy-weight floor impact sound and 1.6 dB in the light-weight floor impact sound per 30 mm increase in thickness were confirmed through the experiments. This study can be viewed as the basic research for the evaluation of floor impact sound insulation performance of CLT.

• Mycobiology
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• v.47 no.4
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• pp.430-440
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• 2019

Fungal contamination of built-in furniture is a frequent problem in Korea when new apartment is built. However, domestic information on the contaminating fungi is very limited. This study was conducted to isolate, identify and characterize the fungi of the problem in one of the apartment houses where the fungi were claimed in the built-in furniture before the house owner moves in. Fungi present in the furniture installed in a main room, dress room, and kitchen side were visually and microscopically confirmed and purely isolated on PDA. The isolated fungi were identified by analyzing the morphological characteristics and nucleotide sequence of the ITS, calmodulin gene, and TEF-1α gene. Aspergillus creber, A. niger, A. pseudoglacus, A. ruber, Cladosporium perangustum and Penicillium commune were identified. Four out of the six fungal species were positive for at least one enzyme in six kinds of extracellular enzyme assays. When these four species (A. creber, A. niger, C. perangustum and P. commune) were inoculated onto four kinds of wood chips of furniture materials, they were able to colonize all of the wood chips. Their settlement was better at 95% humidity condition than at 30% humidity condition. Among the four species, C. perangustum caused the darkest discoloration and secreted the most number of extracellular enzymes. The four species were re-isolated from the colonized wood chips and confirmed as the problematic fungi in the built-in furniture.

• Journal of the Korean Wood Science and Technology
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• v.18 no.4
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• pp.26-40
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• 1990

The plane trees(Platanus occidentalis L.) have been grown in Korea very widely as ornamental garden or street trees but they have not been used as manufacturing materials The proportion of imported wood has been now over 85% of raw materials needed in the wood industry, and therefore, many of studies on the substitution of domestic wood for imported wood and on the increasing the utilization rate of domestic species have been attempted and considered as very important projects to solve. From a this point of view, this study was carried out to investigate solid wood bending properties of plane trees and then to develop their end-uses, and the size of specimens tested was $15\times15\times350mm$ for steaming treatment and they were dried to $15\pm1%$ before bending. The results obtained were as follows: 1. The optimum conditions for solid wood bending processing of Platanus occidentalis are showed in Table 7. 2. The minimum solid-bending radii of Platanus occidentalis were 40mm in steaming treatment. 3. The effect of knots, diagonal grain and decay on the degradation of bending processing properties were very severe. 4. The bending stress was setted successfully through $80^{\circ}C$-15hrs drying after bending and the spring back for 24hr-exposing time was only about 1%.

• Journal of the Korean Wood Science and Technology
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• v.39 no.6
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• pp.521-530
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• 2011

Nowadays, market demand of structural Glulam is growing and diversifying. The durability of Glulam should be significantly considered when they are intended to apply for out-door use such as timber bridge and pergola. This study was aimed to develop the manufacturing process of preservative treated structural Glulam using domestic softwood species. 10 m long structural Glulam were manufactured from domestic pitch pine logs with CuAz-3 preservative treatment. At each manufacturing process, the production yield was evaluated. Finally, bending tests were performed to verify the structural performance of manufactured Glulam. From the results, it was shown that the preservative treatment process hardly influenced on the production yield. But domestic pitch pine was proved to not be suitable for making the preservative treated Glulam due to the large difference of preservative permeability between sapwood and heartwood.

• Journal of the Korean Wood Science and Technology
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• v.12 no.1
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• pp.11-30
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• 1984

This study was executed to offer the basical data needed to the plywood industry as examining on the wood characteristics of veneer species that grow in Korea. According to the aggravation of log import from foreign countries caused by the gradual exhaustion of wood resources in recent years, the study on wood characteristics of veneer species growing in Korea should be carried out preferentially in promotion of the domestic timber utilization and development of it's processing technique for plywood industry. 50 commercial veneer species in this study were selected from 33 genuses, and general macroseopical wood characteristics for them were examined and described by the species. And also keys for the identification based on gross features were briefly prepared and presented by gymnosperm and angiosperm respectively.

• Food Science of Animal Resources
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• v.18 no.1
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• pp.42-49
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• 1998

The contents of holocellulose, one of the main components of the wood, were 83.9% in oak wood and 76.9% in apple wood, respectively. Those of hemicellulose were 16.41 and 20.33%, and in lignin 23.0 and 19.7%, respectively. Six species of domestic oak wood and apple wood were considered to be suitable for smoking materials due to the low content of lignin. Benzo(a)pyrene contents in smoke flavoring prepared with oak wood at 150, 400 and 500$^{\circ}C$ were 0. 4, 3. 7 and 5.6$\mu\textrm{g}$,/kg, respectively. The amounts of phenanthrene were 112.7, 131.4 and 255.9$\mu\textrm{g}$/kg, respectively, in each temperature. The amounts of polycyclic aromatic hydrocarbons(PAH) in smoke flavory were in the order of phenanthrene＞anthracene＞pyrene＞benzo(a)anthracene＞chrysene＞benzo(b)fluoranthens＞benzo(a)pyrene Benzo(a)pyrene contents in smoking extracts prepared with apple wood at 150, 400 and 500$^{\circ}C$ were 0.4, 3.3 and 5.5$\mu\textrm{g}$/kg, respectively. Phenanthrene contents in those samples were 72.7, 100.2 and 220.5$\mu\textrm{g}$/kg, respectively. Contents of each PAH showed the same order as in oak wood.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.199-204
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• 2010

Members used for the Korean traditional joints have been processed by handicraft, especially with domestic red pine species. Dovetail joint is most commonly used in woodworking joinery and traditional horizontal and vertical connections. It is able to be processed much easier to cut by handicraft and machines. However, although it is processed straight forwards, it requires a high degree of accuracy to ensure a snug fit. Also, tenons and mortises must fit together with no gap between them so that the joint interlocks tightly. A few scientific studies on the dovetail joints have been conducted so far. For the effective applications of traditional joints and domestic plantation wood species, dovetail joints were assembled by larch glulam members processed by machine pre-cut. To identify the tensile properties of through dovetail joints, larch glulam with 150 150mm in cross section were prepared. Furthermore, various geometric parameters of dovetai joints such as width, length, and tenon angle, were surveyed. The ends in the mortise was cracked mainly at a low strength level in the control specimens without reinforcements. The maximum tensile strengths of reinforced specimens considering real connections such as capital joint and headpiece on a column, increasedby handicraft, especially with domestic red pine species. Dovetail joint is most commonly used in woodworking joinery and traditional horizontal and vertical connections. It is able to be processed much easier to cut by handicraft and machines. However, although it is processed straight forwards, it requires a high degree of accuracy to ensure a snug fit. Also, tenons and mortises must fit together with no gap between them so that the joint interlocks tightly. A few scientific studies on the dovetail joints have been conducted so far. For the effective applications of traditional joints and domestic plantation wood species, dovetail joints were assembled by larch glulam members processed by machine pre-cut. To identify the tensile properties of through dovetail joints, larch glulam with 150 150mm in cross section were prepared. Furthermore, various geometric parameters of dovetai joints such as width, length, and tenon angle, were surveyed. The ends in the mortise was cracked mainly at a low strength level in the control specimens without reinforcements. The maximum tensile strengths of reinforced specimens considering real connections such as capital joint and headpiece on a column, increased by two times with shear failures on the tenon than the control specimens. The maximum tensile strength was obtained in the specimen of 25 degrees, and no difference was observed in the changes of neck widths.