• Journal of the Korean Institute of Landscape Architecture
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• 제46권6호
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• pp.111-119
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• 2018

This study was carried out to investigate the growth characteristics and propagation methods of the Korean native Amelanchier asiatica, A. arborea, and A. alnifolia as fruit trees for gardens. Due to the lack of recent research on Amelanchier spp., their superficial classification is still unclear and the names are being used interchangeably. The results are obtained as follows : A. arborea and A. alnifolia were globular type multi-stemmed shrubs. A 20-year-old tree of A. asiatica was 7.8m in height, with a 5.2m crown width, with one trunk. As for the morphological characteristics, leaves of A. asiatica were oblong, with an acuminate of, 6.1cm and 3.6cm width, but A. arborea and A. alnifolia had acute obovate leaves. The leaf size of A. alnifolia was the largest among the three species. The flower size of A. asiatica was bigger than that of A. arborea and A. alnifolia. In addition, its petals and flower clusters were also the largest among the three species. The flowering of A. asiatica initiated on April 21 and then bloomed for a duration of 24 days in Osan, while that of A. arborea and A. alnifolia initiated flowering on April 12 and then bloomed for a duration of 22 days in the same location. The fruit of A. arborea and A. alnifolia were green on May 10~12, it changed into purplish red on May 24~26, and its matured on June 1~3. The duration of fruit persistence of A. arborea and A. alnifolia were 48~50 days. On the other hand, A. asiatica showed greenish fruit on May 20, it became red on September 4, and had fallen by October 3. The fruit size was the largest at 1.03cm of height and 1.12cm of diameter in the A. arborea, followed by the big berry of A. alnifolia and the smallest fruit in the native, A. asiatica. It was difficult to root due to the hardwood cutting of A. arborea at a 40% rate of rooting. In the softwood cutting, the rooting rate of A. arborea was increased by the treatment with concentrated IBA, especially at 5,000 and 7,000ppm. The optimum date for cutting was on June 27, when the rooting rate was more than 80%. The most effective method for rooting of A. arborea was rootone or 7,000 ppm IBA treatment on June 27 softwood cuttings, which showed a rooting rate of over 80%.

• Journal of the Korean Wood Science and Technology
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• 제41권3호
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• pp.173-180
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• 2013

This study was carried to provide basic data for the research of the effect of PEG impregnation on preventing wood from cracking during heat treatment. Three popular softwood species were selected for investigating the PEG penetration rate and retention depending on PEG molecular weight, PEG retention after heat treatment and their EMCs. The average retentions of PEG400 were reversely proportional to the basic densities of three species and those of the other PEGs showed similar behaviour as well. It is obvious that PEG retention decreased as PEG molecular weight increased with a species. PEG impregnation increased or decreased the moisture contents of the specimens within 2%, and increased their basic densities by 16.8% as a maximum. The Weight Percentage Losses of PEG400 during heat treatment were the largest among three PEG levels, which implied that lower molecular weight PEG leached more than the highers. There was less difference in EMC between PEG impregnated and control specimens at low RH, but their difference increased at high RH.

• Journal of the Korean Wood Science and Technology
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• 제38권6호
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• pp.470-479
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• 2010

In this study, the visual grading based on the visual characteristics and structural timber bending test were conducted for domestic yellow poplar dimension lumber. Structural performance of domestic yellow poplar dimension lumber was conducted through the evaluation of strength and stiffness. Visual grading rule of yellow poplar dimension lumber did not exist in Korea. Visual grading of yellow poplar dimension lumber was performed according to the NSLB (Northern Softwood Lumber Bureau) standard grading rules including several hardwood dimension lumber. The allowable bending stress was calculated from the results of a visual grading. Compared with NDS (National Design Specification), the yellow poplar dimension lumber showed enough strength for structural uses. In addition, the visual grading was performed according to the KFRI (Korea Forest Research Institute) grading rule to calculated allowable bending stress and to evaluated the feasibility. The yellow poplar was classified into the pine groups by the KFRI criteria regulated by specific gravity. Allowable bending stress based on weibull distribution had became highly than KFRI criteria, as No. 1 (10.0 MPa), No. 2 (7.4 MPa) and No. 3 (4.1 MPa). And the availability of yellow poplar dimension lumber for structural uses had been confirmed. The Modulus of Elasticity (MOE) of domestic yellow poplar dimension lumber had not met the NDS and KFRI criteria. However, for the use of domestic yellow poplar, average values of MOE which obtained through this test were suggested as design value for domestic yellow poplar. Design values were supposed No. 1, 2 (9,000 MPa) and No. 3 (8,000 MPa).

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.385-389
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• 2012

In this study, torrefaction of mixed softwood chips under anoxic condition was performed to improve energy density and maintain consistent quality of biomass. Characteristics of torrefied biomass depending on reaction time (30 min) and temperature (240, 260,$280^{\circ}C$) were investigated. Torrefaction of mixed softwood chips significantly improved the heating value compared to that of untreated biomass. As the torrefaction temperature was increased, the carbon content of torrefied biomass increased from 46.55 to 55.73%, while its hydrogen and oxygen contents decreased from 6.00 to 5.87% and from 30.55 to 27.21%, respectively. Most of hemicelluloses and volatile compounds were removed during torrefaction. The highest heating value was 5132 kcal/kg when torrefaction was performed at$280^{\circ}C$ for 30 min. It implied that the heating value increased by 13% compared to that of original biomass. However, the condition of effective torrefaction was at $240^{\circ}C$ for 30 min when weight loss and energy yield was considered.

• Journal of the Korean Wood Science and Technology
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• 제49권5호
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• pp.462-470
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• 2021

To find out the wood species used in national wood structures in the late Joseon Dynasty, 11 volumes of Yeonggeon-Uigwes were reviewed. It was confirmed that the wood was mainly used for the repair and restoration of palaces, shrines, and fortresses. In the 17th to 20th centuries, the wood species specified in Yeonggeon-Uigwes have revealed either hardwood or softwood. As hardwood species, Juglans mandshurica, Zelkova serrata, Fraxinus rhynchophylla, Betula schmidtii, Paulownia coreana, or Quercus spp. (Quercus aliena; Q, variabilis; Q, dentata; Q, acutissima; Q, mongolica; Q, serrata) were used. As softwood species, Pinus densiflora and Pinus koraiensis were used. Investigation of the wood species is important part because the same species is required as a principle when reparing cultural heritage. In this study, the anatomical images of the wood species were investigated for some samples which were taken from the same species that has been stored in the wood specimen room of the National Institute of Forest Science, instead of the actual wood material used. It was possible to find out the wood species of each member in the wooden cultural heritage buildings by reviewing the Yeonggeon-Uigwes in the late Joseon Dynasty, and the anatomical images of the wood species required for determining the wood species in the repair or restoration of the buildings.

• Journal of Mushroom
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• 제4권3호
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• pp.88-100
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• 2006

This study was performed to investigate the effective components of media of Pleurotus eryngii for bottle cultivation and several alternative material for reducing cost and smooth supply. The results show that Potato starch, Cocoa shell, Corn gluten feed, Soybean flour(solvent extracted), Cottonseed hull, Poultry manure can be replaced in Bean curd dregs of basal substrates. Especially addition of Soybean flour at 2~8% and Poulty manure at 2% in place of Bean curd dregs is effective for mycelial growth of P. eryngii, Also Pine sawdust appears that can be replaced by Softwood sawdust and addition of softwood sawdust at 25.2% is most effective. Addition of $CaCO_3$, at 2~3%, $K_2CO_3$, at 0.2%, $MgSO_4{\cdot}7H_2O$ in 0.1%, $MnSO_4{\cdot}5H_2O$ in 0.05% is effective for mycelial growth of P. eryngii, Activation materials used in this study have not enough benefit for mycelial growth in the financial aspect.

• Korean Journal of Plant Resources
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• 제36권4호
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• pp.390-401
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• 2023

The purpose of this study was to identify the propagation characteristics of Diabelia spathulata (Siebold & Zucc.) Landrein through seeding and cutting methods. The seed germination rate was meager (0.22~3.56%). In hardwood cutting, the highest rooting rate was 36.1% in sand + perlite (2:1) and 37.8% in 1000 PPM of IBA pre-treatment. Softwood cutting showed the highest rooting rate when the cutting diameter was 3 to 5 mm and the cutting length was 7 to 8 cm. In particular, the highest rooting rate of 80% was observed in the sand among the 8 cultivation media treatments. In the case of root cuttings, the rooting rate was 83.3~96.7% in all cultivation media. The highest rooting rate was observed when the diameter of the cutting was 7 to 8 mm, and the length of the cutting was about 10 to 11 cm. Among cutting methods, root cutting showed the highest rooting rate. Division showed a 100% rooting rate regardless of size or growth status. For Diabelia spathulata (Siebold & Zucc.) Landrein, propagation by cuttings was more efficient than seeding. However, Further research on the morphophysiological dormancy and dormancy break of seeds is needed for seed propagation.

• Journal of Mushroom
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• 제2권2호
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• pp.88-96
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• 2004

This study was executed to decide the physiological characteristics of Ferule mushroom. Four strains of Ferule mushroom were tested to select a superior strain in its mycelial growth. The pertinent substrates, temperature and pH ranges for the growth of selected strain were determined. And then, the wood rotting ability and type of the Ferule mushroom were determined. The superior strain F-2 among four strains was selected, on the basis of its vegetative mycelial growth and density on agar media. Mycelial growth of F-2 was the best on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about $25{\sim}34^{\circ}C$ and best at $30^{\circ}C$. The optimum pH range on MYPA was 5.0~6.0. The mycelial growth was mostly stimulated by soluble starch at cont. 1% (w/w) and secondly, maltose among several carabon sources and by mixed solution of YE(0.25%) and ME(0.25%) but not by ME alone. Cell thining and erosion of Pinus rigida wood by the mycelia of Ferule mushroom were found only on a few cell but largely at wood block test, indicating that the softwood rotting ability of Ferule mushroom mycelia was not so good. The result of polarized light microscopy appeared that cellulose of some tracheides showing the S3 layer lost brifringence was degraded by Ferule mushroom. But only part of cellulose of P. rigida wood was degraded by Ferule mushroom, because most of wood cells continued to showing briefingence. A largely degraded ray parenchyma and longitudinal parenchyma cell and partly thinning and erosion of hardwood(Quercus serrata) cell was found and it indicates that the rotting ability of Ferule mushroom mycelia on hardwood was higher than on softwood. It could be concluded that the difference in the wood rot by Ferule mushroom between the hardwood and softwood was made by the difference of chemical constitutions between them, especially in the contents and the types of lignin. Ferule mushroom was considered as white rotter as a result of bavendam test, although more research should be required.

• Journal of the Korean Wood Science and Technology
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• 제47권4호
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• pp.385-392
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• 2019

In our previous study, we investigated the use of ensemble models based on LeNet and MiniVGGNet to classify the images of transverse and longitudinal surfaces of five Korean softwoods (cedar, cypress, Korean pine, Korean red pine, and larch). It had accomplished an average F1 score of more than 98%; the classification performance of the longitudinal surface image was still less than that of the transverse surface image. In this study, ensemble methods of two different convolutional neural network models (LeNet3 for smartphone camera images and NIRNet for NIR spectra) were applied to lumber species classification. Experimentally, the best classification performance was obtained by the averaging ensemble method of LeNet3 and NIRNet. The average F1 scores of the individual LeNet3 model and the individual NIRNet model were 91.98% and 85.94%, respectively. By the averaging ensemble method of LeNet3 and NIRNet, an average F1 score was increased to 95.31%.

• Journal of the Korean Wood Science and Technology
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• 제33권1호통권129호
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• pp.17-20
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• 2005

This research was carried out to examine the FIR (far-infrared rays) emissivity and emission power of five Korean wood species for proving wood as an amenity material. Wood turned out excellent as FIR material with 90~91% emissivity in the range of $5{\sim}20{\mu}m$ at $40^{\circ}C$. No difference was identified in the FIR emissivity and emission power between hardwood and softwood, diffuse porous wood and ring porous wood, and high-density wood and low-density wood respectively.