• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.896-906
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• 2020

Wood deterioration experiments were carried out for 6 months in an intertidal zone of South Korea to monitor the changes in the chemical properties of two types of species, Korean red pine and sawtooth oak. The results of FT-IR spectra and XRD patterns have shown that the chemical properties of the wood did not change significantly during the 6-month burial period. However, the brightness of the surface decreased after burial; the value of the sawtooth oak sample was lower than that of the Korean red pine sample owing to an accumulation of inorganic compounds in cell lumen as observed by ICP analysis. Among the inorganic compounds, sodium and sulfur concentrations increased significantly over the burial period compared with the control. Further, the maximum moisture content decreased from 199% to 136% in the Korean red pine and 62% to 60% for the sawtooth oak. Nevertheless, the major chemical composition of both the wood species did not change significantly during the 6-month burial period, whereas, the crystallinity decreased with an increasing burial period owing to an accumulation of inorganic compounds in the lumen.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.61-71
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• 2000

The effect of the treatment with CCFZ, FR-4, and PEG400 from butt end on the dimensional stability and bending properties was examined. Three softwood species such as red pine, Korean white pine and Japanese larch and three hardwood species such as poplar, alder and oak were investigated in this research. Shrinkage of red pine, Korean white pine, poplar, and alder treated with PEG400 decreased. However, there was no significant decrease of shrinkage in Japanese larch and oak. The decrease of shrinkage when moisture content changed from about 20% to 10% was larger than that at any other phase. In regard to the effect of treatment on bending properties, bending MOE and MOR of all specimens treated with PEG400 decreased significantly. Especially in the case of red pine, poplar, and alder treated with PEG400, bending MOR reduced 9%, 14%, and 12%, respectively. Reductions of MOR of the hardwood was also much larger than that of the softwood. However, in all species, treatment with CCFZ and FR-4 did not affect the change of bending MOE and MOR significantly. Comparing the large specimen which also included heartwood with the small specimen which included only treated sapwood, there was a difference in the change of bending MOE and MOR between them. The large specimens of Korean white pine, alder and Poplar, which had a relatively low proportion of sapwood(18~22%), showed the decrease of MOR by 11~13% more than that of small specimens, while red pine, Japanese larch and oak, which had a relatively high proportion of sapwood(35~40%), showed little decrease. It means that bending MOE and MOR of structural wood treated from butt end should be considered in terms of sapwood proportion as well as effect of treated chemicals.

• 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 Forest and Environmental Science
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• v.37 no.4
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• pp.269-279
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• 2021

This study was carried out to introduce the forest cover types of the Baekdudaegan inhabiting the number of native tree species. In order to understand the vegetation distribution characteristics of the Baekdudaegan, a vegetation survey was conducted on the major 20 mountains of the Baekdudaegan. The vegetation data were collected from 3,959 sample points by the point-centered quarter method. Each mountain was classified into 4-7 forests by using various multivariate statistical methods such as cluster analysis, indicator species analysis, multiple discriminant analysis, and species composition analysis. The forests were classified mainly according to the relative abundance of Quercus mongolica. There was a total of 111 classified forests and these forests were integrated into the following nine forest cover types using the percentage similarity index and by clustering according to vegetation type: 1) Mongolian oak, 2) Mongolian oak and other deciduous, 3) Oaks (Mixed Quercus spp.), 4) Korean red pine, 5) Korean red pine and oaks, 6) ash, 7) mixed mesophytic, 8) subalpine zone coniferous, and 9) miscellaneous forest. Forests grouped within the subalpine zone coniferous and miscellaneous classifications were characterized by similar environmental conditions and those forests that did not fit in any other category, respectively.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.56-65
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• 2009

In Korea, Red pine(Pinus densiflora) stands at a very important place, historically, culturally, and emotionally and it is one of the tree species that can produce domestic timber as forest resources economically. The growing space for Red pine forest in Korea is gradually reducing while the space for deciduous tree forests including oak series is gradually increasing. Thus, it is required that the research work should be done on renewal for pine forest retention and its related forest management practices. This research aims at developing stable, sustainable management forests and inducing nature renewal by grasping growth environment and succession process through the pattern of stand and structure analysis of the red pine(Pinus densiflora) for central region. The pine forests in central region were classified into four communities, such as Acer pseudo-sibolianum, Quercus acutissima, Lindera erythrocarpa, and Pinus densiflora and they are showing different characteristics by pattern according to their growing district. There appeared a lot of red pines in the upper layer, but there existed high weight of broad-leaved forest tree species, such as oak series in the middle layer and the appearance of the red pine was meager in the lower layer. Therefore, it appears that the red pine has a high influential ecological strength in terms of correlativity; however, if the red pine in tree layer is dead by aging in nature state with the lapse of time, it is considered that oak species, such as Quercus mongolica, Quercus variabilis, and Quercus serrata will be dominant below sub-tree layer. In addition, there appear differences in characteristics and growth pattern of the red pine forest depending on stand pattern, so it is considered that a differential application method should be employed in the pine forest management.

• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.37-44
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• 1996

포수상태(包水狀態)의 루부라참나무(Quercus rubra) 시험편을 3가지 등온조건(等溫條件)에서 건조한 결과를 비정상상태(非正常狀態)의 확산(擴散)모델로 추정한 결과와 비교하였다. 표면이 충분히 젖은 상태인 건조초기에는 불안정(不安定)한 확산현상(擴散現象)이 관찰되었으나, 함수율(含水率)별 건조속도의 변이를 Fick's의 확산법칙과 비교할 때 유사한 형태를 보였다. 실험에서 얻은 건조조건별 건조곡선은 확산모델의 수치해석(數値解析) 결과와 거의 일치하였으며, 같은 평위함수율(平衛含水率) 조건에서 건조온도의 증가는 목재표면 보다 내부의 함수율 변화에 더 크게 영향하여 결과적으로 낮은 온도에서의 건조조건이 목재 내의 수분경사(水分傾斜)를 급하게 하는 것으로 밝혀졌다. 본 연구를 통해 목재 건조 중의 내부에 발생하는 수분경사를 추정하는데 비정상상태의 확산모델이 모든 함수율 범위에 걸쳐 유용하게 사용될 수 있음이 밝혀졌다.

• Mycobiology
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• v.34 no.1
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• pp.30-33
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• 2006

To screen additives and their mixed ratio suitable for the mycelial growth and fruiting body formation of Oudemansiella radicata in the oak sawdust, additives such as rice bran, fermented soybean powder and wheat bran were used. Generally, the mycelial growth of O. radicata has been stable on oak sawdust mixed with rice bran of $5{\sim}20%$. In case that O. radicata was cultured for about 30 days at $22{\pm}1^{\circ}C$ under the illumination (350 lux) of 12 hours and moisture condition of $90{\pm}5%$, the primordia have been formed gradually from red-brown crusts covering the surface of oak sawdust media. Based on the experimental results from 9 strains of O. radicata, fruiting bodies were produced widely on oak sawdust medium mixed with rice bran of 5 to 30%. Even though fruiting bodies of O. radicata have been produced well on oak sawdust media mixed with rice bran, fruiting bodies of O. radicata were produced intensively on oak sawdust media mixed with rice bran of 10%. Therefore, this result will provide a basic information for commercial production of fruiting body of wild O. radicata. This result is the first report associated with an artificial fruiting body formation of O. radicata in Korea.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2003.07a
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• pp.81-81
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• 2003

우리 민속전통주의 참나무 oak통을 이용한 저장주의 가능성을 규명하기 위하여 상법에 의하여 쌀로 제조한 증류주를 용량 10L의 수입 참나무(oak)통에서 실온 25로 5개월부터 9개월까지 숙성한 숙성주와 숙성하지 않은 증류주의 성분함량 변화를 측정하여 다음과 같은 결론을 얻었다. 1) 유기산은 검출되지 않았으며 다만 7개월 이상 숙성주에서 acetic acid 가 0.023 ∼ 0.033%로 미량 검출되었다. 2) 총 유리아미노산의 함량은 숙성 기간이 경과할수록 감소하였다. ) 휴젤유 함량을 측정한 결과 숙성 기간이 길수록 감소하였으며 휴젤유 중 가장 많은 성분은 isopropyl alcohol이었다. 4)휘발성 향기성분은 숙성기간이 경과함에 따라 이취를 생성할 수 있는 aldehyde나 ketone류가 감소하였고 신선한 과실향이나 꽃향기 등의 향기 성분인 ester류가 증가하여 숙성 5개월째에는 oak 숙성주로서 가장 독특한 향을 갖는다고 예측할 수 있었다. 5) Gas chromatography-olfactometry를 이용하여 각각의 시료들의 향기특성을 관능 평가하여 동정한 결과 전반적으로 green 및 herb note가 우세한 숙성기간 8개월 숙성주가 가장 우수한 것으로 판단되었다. 6) 전체적인 색상 비교 결과 기준값이 되는 oak 숙성을 하지 않은 증류주보다 숙성기간이 오래 경과된 숙성주일수록 점점 높아지는 경향을 보였다. 또한 UCS graph에서 보면 기준값 보다 숙성된 시료가 탁하다는 것을 나타냈고 색상 선에서는 기준시료보다 R(red)에 가까웠다. 숙성기간이 긴 발효주일수록 명도는 낮았다.

• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.103-112
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• 2016

To compare seed components of plus trees, seed powder ground after seedcoat removal was analyzed for two oak species, i. e., Quercus monglica (white oak) and Quercus variabilis (red oak), which are typical oak trees in Korea but have different fruiting characteristics. Thus we aimed at analyzing and comparing many ingredients including minerals, sugars, etc. Two species were similar to each other in the content of water, crude ash, crude protein and carbohydrates, but crude lipid content in Q. variabilis was 2.5 times higher than that in Q. mongolica. Crude proteins of Clone 124 was 1.5 times higher than that of Clone 75 in Q. mongolica. Crude lipid content showed the highest value in Clone 0511 of Q. variabilis, and more phosphate and iron was found in Q. monglica than in Q. variabilis. Glucose showed 85.4% and 88.3% on average of the total monosacchrides in two species, and galactose and arabinose were also found. In the content of phosphate, iron, and crude lipid, differences were found between two species and among clones of two species.

• Journal of the Korean Arthroscopy Society
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• v.5 no.2
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• pp.85-91
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• 2001

Purpose : The purpose of this study was to determine the clinical outcome of meniscal repairs according to tern location and combined injury. Materials and Methods : From 1994, 73 meniscal repairs were underwent by arthroscopy and followed more than 1 year. The locations of torn meniscus were 29 red-red Bone, 36 red-white zone, 8 white-white zone. Twenty-six patients also had combined lesion including ACL injury 17 cases and treated simultaneously. Clinical result was evaluated by OAK system. Result : Healing rates(above good) were $94\%$ in isolated injury and $88\%$ in combined injury, especially $94\%$ in ACL injury. The result according to tern location were $90\%$ in red-red zone, $91\%$ in red-white zone, all in white-white zone. Conclusion : Meniscus tear with ACL injury should be repaired by arthroscopy, simultaneously. The meniscal tear of white-white zone could be healed by arthroscopic meniscal suture.