• Journal of the Korean Wood Science and Technology
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• 제17권3호
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• pp.20-27
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• 1989

This experiment was made to find the peripheral variations of annualring widths, the cell dimensions, microfibril angles and bulk densities within each annual-ring of horizontal-growing young tree of beech(Betul a platyphylla var. japonica) and Oak (Quercus variabilis) from the tension to the opposite side. Also a comparision between the features of the obnormal annual ring for horizontal-growing year and normal annual ring for the straight-growing years was made. The dimension of propotion of the element, the microfibril angles and the bulk density decreased or increased continuously toward opposite side which showed minimum or maximum value. The dimension of elements the microfibril angles and the bulk density decreased or increased continuously towards opposite side which showed minimum or maximum value. The dimension of elements. the microfibril angles and the bulk density in the normal annual rings were similar to those in the lateral woods. whereas were significantly more different in the tension wood than in the opposite wood. The features of typical opposite wood in the hardwoods were influenced by the locations within the inclined stems than effects of the decrease in the annual ring width. The oppostie woods in hardwoods did not conform to the tension wood and lateral wood. The abnormal annual ring included the opposite wood, lateral wood similar to normal wood and tension wood having specialized structure even in the same annual ring.

• The Korean Journal of Ecology
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• 제16권3호
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• pp.305-316
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• 1993

Stands profiles, yearly changes in growth of annual rings, age and diameter structure, and spatial distribution pattern of individuals in the Pinus densiflora stands around the Yeocheon industrial complex were investigated. Growth of annual ring in Pinus densiflora, which survived when vegetation of this area was damaged by air pollutants, was suppressed for about 10 years since 1974 when factories in this area began to operate, but since then such suppressed growth tended to be recovered. It was supposed that the suppresed growth was originated from air pollution and that improvement of growth since the suppressed period was due to the release from competition with them by death of neighbouring trees and the resuction of the amount of air pollutants. Physiognomy of Pinus densiflora stands showed mosaic pattern composed of different patches. Spatial distribution pattern of individuals an stand profiles were similar to those of Pinus densiflora stands regenerated after natural and artificial disturbances. In an age distribution diagram, age of Pinus densiflora population ranged from 1 to 33 years, Among these individuals were recrited corresponded to the suppresed period of growth of annual ring in Pinus densiflora survived when the vegetation was damaged by air pollution. On the other hand, from the result of analysis of frequency distribution diagram of diameter, it was postulated that even if whis Pinus densiflora community can be maintained as it is for the time being, it might be changed to Quercus community with the lapse of time.

• 한국가구학회지
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• 제10권2호
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• pp.55-61
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• 1999

This research was carried out to investigate the fundamental properties such as the structure of annual ring, density distribution, compressive strength with parallel to grain, relative crystallinity, and microfibril angle of Gumgangsong(Pinus densoflora for. erecta Uyeki). The wood specimens, Gumgangsong and Sonamu(Pinus densiflora S. et Z.), for this experiment were prepared at Ulijingoon Sokwangri and Kyungpook university's forest in Kyungpook province, respectively. Average annual ring width is $2.0mm{\pm}0.3$ in heartwood of Gumgangsong. The respectively of heart wood was over 60 percent in Gumgangsong and 20~50 percent in Sonamu. Heartwood density were ranged from 0.5 to $0.8{\;}g/cm^3$ in Gumgangsong and from 0.4 to $0.5{\;}g/cm^3$ in sonamu. Compressive strength in Gumgangsong and Sonamu was about $30{\pm}5MPa$ and $25{\pm}5MPa$, resepectively. But the relative crystallinity and microfibril angle of two species were not different clearly. From these results of Gumgangsong and Sonamu, therefore, it was considered the main difference factors for both species were annual ring width and heartwood percentage.

• 한국가구학회지
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• 제17권4호
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• pp.109-114
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• 2006

An investigation was carried out for the annual ring width, longitudinal tracheid diameter and wall thickness in different tree heights for Pinus koraiensis Sieb. et. Zucc. The annual ring width increased along with the tree height, however the tracheid diameter and wall thickness decreased with the tree height. Tracheid wall thickness was found the thickest at 2.0m from the above ground samples and it increased gradually from pith to bark. Radial tracheid diameter was found to be larger than that of tangential tracheid diameter in earlywood. But, it was found to be the opposite in latewood. In earlywood, the average values of tracheid wall thickness was found the range of $2.1-3.0{\mu}m$, whereas, in latewood, it was $2.4-4.2{\mu}m$.

• 건축역사연구
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• 제15권2호
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• pp.23-38
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• 2006

During the repair and restoration of the Daewoongjeon Hall of Youngguksa Temple, species identification and tree-ring dating for both present wood elements and charred ones excavated under the Hall, were conducted. The species of 74 wood elements of Daewoongjeon Hall, were identified as Pinus densiflora Sieb. et Zucc. and only 1 was identified as exotic Pinus species. The latter wood, which was used in the laths, seems to have been replaced during past repairs. Many documentary records and various artifacts pertaining to Youngguksa Temple are being excavated, but none described precisely the construction date of the present Daewoongjeon Hall. Also, from beneath the Daewoongjeon Hall, cornerstone and foundation of previous building and several charred wood elements were excavated. In comparing the direction of the stone columns of foundation of the previous structure and the existing Daewoongjeon Hall, the previous structure was rotated in an angle of approximately $15^{\circ}$. Therefore, in order to find the association of the previous structure with the present Daewoongjeon Hall, tree-ring dating was conducted. The dating of 41 original timbers and 14 roof-filling timbers of the present construction elements revealed that the last annual ring was of A. D. 1703 with complete latewood, indicating that those woods was cut some time between the autumn of 1703 and spring of 1704, and the building was erected in 1704 when we assume no period of wood storage. The year of the last annual ring of the charred elements, which were excavated from beneath the Daewoongjeon Hall, was analyzed as 1674. The cutting year of the woods used for the present building began in 1698, therefore, it can be presumed that the Daewoongjeon Hall before the fire was a structure that was elected shortly after 1674 and that a catastrophic fire occurred some time between 1674 and 1698.

• The Korean Journal of Ecology
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• 제16권3호
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• pp.317-327
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• 1993

Stands profiles, yearly changes in growth of annual rings, age and diameter structure, and spatial distribution pattern of individuals in the Pinus densiflora stands around the Yeocheon industrial complex were investigated. Growth of annual ring in Pinus densiflora, which survived when vegetation of this area was damaged by air pollutants, was suppressed for about 10 years since 1974 when factories in this area began to operate, but since then such suppressed growth tended to be recovered. It was supposed that the suppresed growth was originated from air pollution and that improvement of growth since the suppressed period was due to the release from competition with them by death of neighbouring trees and the resuction of the amount of air pollutants. Physiognomy of Pinus densiflora stands showed mosaic pattern composed of different patches. Spatial distribution pattern of individuals an stand profiles were similar to those of Pinus densiflora stands regenerated after natural and artificial disturbances. In an age distribution diagram, age of Pinus densiflora population ranged from 1 to 33 years, Among these individuals were recrited corresponded to the suppresed period of growth of annual ring in Pinus densiflora survived when the vegetation was damaged by air pollution. On the other hand, from the result of analysis of frequency distribution diagram of diameter, it was postulated that even if whis Pinus densiflora community can be maintained as it is for the time being, it might be changed to Quercus community with the lapse of time. Regeneration; Pinus densiflora; Air pollution; Annual ring; Age structure; Diameter structure; Quercus spp. In these analyses, factors for individual recognition and species recognition were suggested.

• The Korean Journal of Ecology
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• 제13권3호
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• pp.191-202
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• 1990

For the maximun yield of the forest trees in the forest management, the growth of annual ring area of the major forest trees was analysed in the four areas in South Korea. The time to the maximum productivity and the optimum cutting time for the maximum yield were estimated. The growth curve of annual ring area showed sigmoid like that of other organisms. Only the growth coefficient among the areas between Fraxinus rhynchophylla and Pinus koraiensis represented significance (5% level). The growth coefficient among forest trees between Pinus densiflora and Abies holophylla, Larix kaempferi and Carpinus laxiflora, Larix kaempferi and Quercus mongolica, Larix kaempferi and Quercus serrata, Larix kaempferi and Pinus koraiensis, and Larix kaempferi and Abies holophylla represented significance (5% level). Among eight forest trees, the time to maximum productivity (tm) of Larix kaempferi was the earliest (21.4 year), and Abies holophylla was the latest (91.9 year). The optimum cutting time for the maximum yield (tc) of L. kaempferi was the earliest (29.4 year) and that of A, holophylla was the latest (122.2 year) of all communities. The optimum cutting time for the maximum yield was 1.33 times as late as the time to the maximum productivity. If the growth of annual ring area as the forest tree for wood is regarded, L. kaempferi and P. densiflora are thought to be more economical than A. holophylla and P. koraiensis.

• Journal of the Korean Wood Science and Technology
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• 제24권3호
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• pp.18-27
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• 1996

The feasibility of using stress-wave technique in the transverse direction for the assessment of early stages of decay was investigated using compression test specimens having different annual ring orientations subjected to decay by Tyromyces palustris for various time intervals. Decay detection, quantitative assessment of decay, and the prediction of residual strength of decayed wood with less than five percent weight loss can be feasible using stress-wave parameters (wave velocity, wave impedance, and stress-wave elasticity) and their percent reduction due to decay, measured by stress-wave technique in the transverse direction. The use of stress-wave technique in the transverse direction for the application of this technique to structural members in service is desirable, when considering the easiness of attachment of accelerometers of stress-wave measuring device on the surface of members and also accurate detection of localized decayed areas. In stress-wave technique in the transverse direction, stress-wave parameters measured were different according to the angles between wave propagation path and annual ring, due to the anisotropy of wood structure. Therefore, it is recommended to use percent reduction in stress-wave parameters instead of stress-wave parameters. This evaluation method using percent reduction in stress-wave parameters is ideal when it is impossible to observe annual ring orientation on the transverse surface of wood.

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.56-61
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• 2014

Macroscopic and microscopic characteristics of Yellow-hearted pine and Red pine were investigated. Wood color, annual ring width and latewood percentage were observed by the naked eye. Anatomical properties as the structure of three sections and cell dimensions were examined by an optical microscopy. As a result, the color of bark in Yellow-hearted pine was Reddish-grey, and Red pine showed brown or gray. The color of heartwood and sapwood in Yellow-hearted pine was deep-yellow to brown and creamy-white. And the color of heartwood and sapwood in Red pine was light-brown and light-yellow. The annual ring width of Yellow-hearted pine was narrower than that of Red pine, and the latewood percentage of Yellow-hearted pine was a little higher than that of Red pine. There was no significant difference in the anatomical characteristics between Yellow-hearted pine and Red pine.

• Journal of the Korean Wood Science and Technology
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• 제6권1호
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• pp.15-23
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• 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.