• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.1-8
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• 2005

The initiation and cessation of cambial activities were investigated to find out the growth characteristics of the major species growing in Chuncheon, Korea. The division of cambial zone in Pinus densiflora and Pinus koraiensis began from the middle of March through the end of March. The activity of cambial zone in P. densiflora and P. koraiensis was vigorous from the end of May through the middle of July. During this period the number of cells increased rapidly in radial direction. However, the number of cells in P. densiflora was gradually increased. The division of cambial zone in ring-porous wood, such as Quercus mongolica and Robinia pseudoacacia began in the middle of March, before the formation of vessel. The division of cambial zone in diffuse-porous wood, such as Cornus controversa and Prunus sargentii, began in early April, and then the formation of vessels began after one to three weeks. It was considered that the cambial zone in softwood was ceased from the beginning of November, whereas cambial activities in hardwood ceased in the middle of October. Consequently, the formation of growth ring was different among the species, even though the trees were grown under the same conditions.

• Journal of Korean Society on Water Environment
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• v.32 no.2
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• pp.205-215
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• 2016

In order to improve water quality in the Paldang Lake, a riparian vegetation belt, treatment wetland, and artificial floating island were designed for introduction in the upland field, the estuary of tributaries, and the section of water facing mountainous land, respectively. We synthesized vegetation information collected from a reference river and found that herbaceous, shrubby, and tree vegetation zones tended to be dominated by Phragmites japonica, Phalaris arundinacea, etc.; Salix gracilistyla, S. integra, etc.; and S. koreensis, S. subfragilis, and Morus alba, respectively. In our plan, the herbaceous vegetation zone, which is established on floodplains with a high frequency of disturbance, will be left in its natural state. A shrubby vegetation zone will be created by imitating the species composition of the reference river in the ecotone between floodplain and embankment. A tree vegetation zone will be created by imitating species composition on the embankment slope. In the treatment wetland, we plan to create emerged and softwood plant zones by imitating the species composition of the Zizania latifolia community, the Typha orientalis community, the P. communis community, the S. integra community, and the S. koreensis community. The floating island will be created by restoring Z. latifolia and T. orientalis for water purification purposes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.6
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• pp.153-163
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• 2009

This study was carried out to offer ecological restoration plan of local streams by analyzing the vegetation and flora around four local streams (Pungchoncheon, Namchangcheon, Ganggicheon, Woncheoncheon) in Namwon. Flora and vegetation investigation was done at April 2007 to August 2007, and June 2009. The 194 of vascular plants were identified which contain 53 families, 143 genera, 194 species. The Family frequencies arranged by the order of Family Compositae (14.4%), Family Gramineae (13.4%) Family Leguminosae (6.7%) and Family Polygonaceae (5.2%). The naturalized plants were listed as 33 species, and their naturalization ratio and urban index were found to be 17.0%, and 12.2%, respectively. In this study a total of 21 relev$\acute{e}$s collected and analyzed. 6 plant communities are differentiated : Riverine softwood forests (Phragmites japonica-Salix gracilistyla community), Perennial herb vegetations on lotic water zone (Phragmites japonica community, Phalaris arundinacea community), Perennial herb vegetations on lentic water zone (Persicaria thunbergii-Typha orientalis community, Phragmites communis community), Annual or biennial vegetations on waterside (Persicaria thunbergii community). Species showing the higer value in the plant communities were Persicaria thunbergii, Phragmites japonica, Artemisia princeps, Humulus scandens, Bidens frondosa, Oenanthe javanica, Agropyron tsukusinense var. transiens, Stellaria aquatica, and Lactuca indica var. laciniata.

• Journal of the Korean Wood Science and Technology
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• v.49 no.6
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• pp.574-590
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• 2021

International efforts to prevent illegally logged wood are expanding around the world. The "Legal Wood Trade Promotion System" was enacted in Korea in 2019 to strengthen the legal import and distribution of commercial wood in Korea. Since then, this system has promoted and ensured that the imported wood and wood products are legal with respect to the country of origin, wood species, and harvested area. As verification methods, DNA analysis technology and anatomical analysis using a microscope are mainly used in conjunction. Therefore, in this study, wood species of plywood were identified by analyzing the anatomical characteristics of various wood products for the first time. Douglas fir (Pseudotsuga menziesii (Mirb.) Franco.) and larch (Larix kaempferi (Lamb.) Carriere) plywoods (7, 9 ply) were obtained from four companies that supply plywood in Korea. After cutting each company's plywood to a size of about 1 cm³, the layers from top to bottom were separated into single layers, and three sections were observed using an optical microscope. The results revealed that the plywood was composed of a mixture of softwood and hardwood wood species, pine wood species, poplar wood species, or a mixture of larch and pine wood species. Identification of wood species using microscopy is important and can enable the scientific analysis and verification of various wood products, including plywood, imported from countries where the likelihood of indiscriminate distribution of illegal wood and illegal logging is high.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.197-202
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• 2007

This study is conducted to investigate the factors affecting lumber conversion rate of sawmill industry in South Korea. Data were obtained from the survey of 38 sawmills in all geographic regions of South Korea. The variables examined in this study were region, softwood/hardwood log, domestic/imported/both log, the number of power-driven carriages (PDC) installed, the year when and country where PDCs was manufactured, the horse power of PDC, the number of labors required to operate each PDC, the sawing capacity of mill (mill size), and the types of major product and by-products. The lumber recovery factor (LRF) of sawmills were significantly influenced by the origin of logs, level of PDC automation, sawmill size, and size of logs (measured in diameter and length) while not by the location of the mill, types of major product and by-product, log species, and characteristics of PDC. Although these results provide useful information for understanding the technological characteristics of the Korean sawmill industry, further investigation with larger sample is necessary to reveal the more reliable characteristics of sawmill industry in South Korea.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.6
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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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• 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.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.64-71
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• 2005

In this study, we attempted to apply ultrasonic treatment for the preservative treatment of two softwood species, Korean pine and Japanese red pines to evaluate its effectiveness. Wood samples were submerged in oilborne preservative, copper naphthenate (NCU) and waterborne preservative, alkyl ammonium compound (AAC) and then treated with ultrasonic wave of 40 kHz, 400 W. After the treatment, the retention and penetration depth of these preservatives in the specimens were measured as a function of treatment time. Both the retention and penetration depth were continuously increased with increasing the treatment time up to 120 hours, where the retention reached about 95% by the application of AAC and the penetrating depth of 95% and 83% by the application of NCU, respectively for both species. The results of electronic microscopic observation showed that the improved retention capacity could be attributed to air deflation, wood extractive deflation working of ultrasonic wavelength, and destruction of wood pits which served as the pathway of preservatives. The results suggested that the use of ultrasonic treatment could be applied to thick wood veneers for the production of laminated wood products.

• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.281-290
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• 2011

We analyzed the basic characteristics and adsorption property of carbonized materials from thinning byproducts of major Korean wood species for evaluating as charcoal making raw material. Yield of charcoal was decreased with increasing the carbonization temperature for all wood species. Refining degrees was 9.0 at $400^{\circ}C$, 3.3~5.0 at $600^{\circ}C$ and 0 at $800^{\circ}C$, and was no difference among wood species. With increasing the carbonization temperature, the fixed carbon content was also increased, and charcoal from softwoods had more fixed carbon content than that from hardwoods. Specific surface area was increased with increasing the carbonization temperature, softwood charcoal had more specific surface area than that of hardwood. Pinus rigida showed the highest specific surface area. In formaldehyde removal by charcoal, some materials had highest at $600^{\circ}C$ and the others had highest at $800^{\circ}C$. Pinus koraiensis, Qurcus acutissima and MDF showed maximum formaldehyde removal ability at $600^{\circ}C$. Ethylene gas removal ability of charcoal was increased with increasing the carbonization temperature, and the charcoal from Pinus rigida and Robinia pseudoacacia had higher ethylene gas removal ability than the other species.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.96-103
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• 2003

This study was conducted to evaluate the tensile properties of metal plate connector for the domestic major softwoods, such as Korean red pine, Korean white pine, and Japanese larch. The maximum tensile load of Korean red pine was 3,612kgf in AA type, it was 1.2 and 1.7 times higher load than that of Japanese larch and Korean white pine. In EA type, it was 2,704kgf, and 1.1 and 1.5 times higher than the loads of Japanese larch and Korean white pine. The failure modes of metal plate connector were metal plate withdrawal, plate tensile failure, and wood shear block failure. The failure mode of Korean red pine connector was tensile failure of plate, that is reason of the high tensile load resistance for metal plate connections in Korean red pine. The mechanical properties of metal plate connector could be predicted by the Foschi model parameter. In the initial stage, the Korean red pine connector was stiffer than the other species. The design values for metal plate connector per tooth was 25, 22, and 15kgf for Korean red pine, Japanese larch, and Korean white pine in AA type and 19, 17, and 13kgf in EA type.