• 한국산림과학회지
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• 제96권2호
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• pp.222-226
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• 2007

This study developed the Korean roundwood import prediction model using vector autoregressive (VAR) method. The roundwood was divided into softwood and hardwood by species. The VAR model of roundwood import was specified with two lagged endogenous variables, that is, roundwood import volume and roundwood import price. The results showed that the significance levels of F-statistics in the softwood and hardwood roundwood import equations rejected the hypothesis that all coefficients are zero. So, we concluded that roundwood import volume can be explained by lagged import volume and lagged import price in Korea. The coefficient signs of all variables were as expected. Also, the model has good explanatory power, and there is no autocorrelation.

• Journal of the Korean Wood Science and Technology
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• 제31권6호
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• pp.60-66
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• 2003

Mycelial growth of L. edodes by supplement nutrition of softwood was studied on a sawdust medium. The sawdust used was from the following softwood species : Larix leptolepis, Pinus densiflora and Pinus koraiensis. The added nutritions consisted of carbon nutritions(sucrose, active carbon, xylose, glucose, paper pellet), nitrogen nutritions(potassium nitrate, ammonium chloride, asparagine, glutamic acid) and vegetable oil(rice bran oil). The sawdust medium was a mixture of 76% sawdust, 20% rice bran, 3% carbon nutrition, 0.4% nitrogen nutrition and 0.6% calcium carbonate. Following addition of carbon and nitrogen nutritions on the sawdust medium proved most suitable : L. leptolepis (glucose, glutamic acid), P. densiflora (active carbon, asparagine) and P. koraiensis (xylose, glutamic acid). The highest mycelial growth was obtained from sawdust medium of optimum condition with 97% of L. leptolepis, 110% of P. densiflora and 98% of P. koraiensis. This study has provided useful preliminary information for the cultivation of L. edodes.

• Journal of Forest and Environmental Science
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• 제26권2호
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• pp.75-82
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• 2010

The biometry, morphological properties and chemical composition of bagasse, corn, sunflower, rice, and rapeseed residues plants were analyzed. The results revealed differences in biometry properties and chemical composition of the different types of agricultural resides investigated. The greatest proportion of fiber length (1.32 mm) and cellulose (55.56%) was found in residues of bagasse plants, with a low ash (1.78%) and lignin (20.5%). The lignin of all types of agricultural resides was less than hardwood and softwood. In addition, the rice and rapeseed residues plants had highest amount of ash and extractive component. The slenderness and flexibility ratios of the all types of agricultural resides fibers were similar to some of hardwood and softwood species.

• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.450-457
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• 2020

Single pellet press technology allows for fast, low-cost, and small-scale tests to investigate pelletizing characteristics. We estimated proper compression ratios for five Korean domestic wood species through predicted relationships between pelletizing pressure P_x and compression ratio based on experimental data obtained from a single pellet press unit. The pressures required to obtain a 6-mm-diam pellet of density 1200 kg/㎥ were estimated as 111 MPa for Populus davidiana, 133 MPa for Robinia pseudoacacia, 136 MPa for Quercus mongolica, 97 MPa for Pinus densiflora, and 127 MPa for Pinus rigida. On the basis of these pressures, we estimated proper compression ratios to be within the range 7.676-8.410 for these species, and we found the compression ratios needed for hardwood species to be somewhat higher than those needed for softwood species to obtain the pellet density of 1200 kg/㎥.

• 한국산림과학회지
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• 제97권1호
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• pp.45-52
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• 2008

본 연구의 목적은 MDF산업의 지속적이고 안정적인 육성을 위해 MDF 생산장기전망에 의한 침엽수 원목공급방안을 제시하고자 하는 것이다. 이를 위해 고전적최소자승법(Ordinary Least Squares Method, OLS)을 이용하여 장기공급함수모델을 개발하였다. 그 결과 MDF의 국내 생산량이 2005년 1,653천$m^3$에서 2050년 2,041천$m^3$으로 증가하는 것으로 전망되었다. 국산 침엽수원목의 MDF 원자재 공급량은 2050년에 2,041천$m^3$의 MDF를 생산하는데 약 1,355천$m^3$이 소비되는 것으로 나타났다. 현재 MDF원자재로 사용되고 있는 리기다소나무의 경우 2050년도에 국산재 원목공급에 필요한 벌채면적은 10,828ha인 것으로 추정되었다. 낙엽송은 9,160ha의 벌채면적이 필요한 것으로 추정되었다. MDF생산의 국산원목사용량의 구성비 시나리오를 35%, 45%, 55%의 3가지로 나누어서 2050년에 침엽수 수종별 예상 연간 벌채량과 총 조림면적을 구하였다. 벌채면적을 기준할 경우 낙엽송을 식재하는 것이 유리하지만 각 수종별 용도 및 생육적 특성이 있으므로 MDF원자재를 공급하려고 하면 어느 정도 이러한 점을 고려한 조림정책이 이루어져야 할 것이다. 그리고 리기다소나무 벌채 후 활엽수 조림정책을 실시하더라도 현재의 MDF 보드산업의 안정적인 육성을 위해서는 MDF의 원자재 공급에 필요한 침엽수종의 일정 면적이 유지 및 관리되는 것이 필요하다.

• Journal of Ecology and Environment
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• 제38권4호
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• pp.405-413
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• 2015

We classified the streamside plant community by phyto-sociological method and analyzed the relationship between environment factors and vegetation structure by using the classification and ordination method. We found that twenty one plant communities were classified according to dominant species at the natural streamside valley forest with surveying the 65 quadrats (10 m × 10 m). From the survey results, the hardwood plant communities were classified as streamside valley forest and the softwood plant communities as riparian forest according to the degree of flooding. The valley forest had a distribution of 17 plant communities which was 65% (42 quadrats) of 65 quadrats: Maackia amurensis community, Betula davurica community, Quercus variabilis community, Pinus densiflora community, Q. serrata community, Prunus sargentii community, and Meliosma oldhamii community etc. The riparian forest had a distribution of four plant communities which was 35% (23 quadrats) of 65 quadrats: Salix koreensis community, S. rorida community, S. purpurea var. japonica community, and S. glandulosa community, etc. From the two-way indicator species analysis (TWINSPAN) analysis, we found indicator species Oplismenus undulatifolius and Lindera obtusiloba for the streamside valley forest and Humulus japonicus, Phragmites japonica, and S. koreensis for the riparian forest. From the results of the canonical correspondence analysis (CCA), coordinates, altitude, and stream structure showed low correlation to the distribution of the plant community. Therefore, it seemed that valley forest and riparian forest were distinguished by the stream gradient and waterway width which determined by the stream water level.

• 한국가구학회지
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• 제28권3호
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• pp.248-258
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• 2017

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood Thuja orientalis L., diffuse-porous wood Gmelina arborea Roxb., and ring-porous wood Phellodendron amurense Rupr., Longitudinal flow was considered from bottom to top while the radial flow was considered from bark to pith directions. In radial direction, ray cells and in longitudinal direction tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents(MC). The variation of penetration speed for different species was observed and the reasons behind for this variation were explored. The highest radial penetration depth was found in ray parenchyma of T. orientalis but the lowest one was found in ray parenchyma of P. amurense. The average liquid penetration depth in longitudinal trachied of T. orientalis was found the highest among all the other cells. The penetration depth in fiber of G. arborea was found the lowest among the other longitudinal cells. It was found that cell dimension and also meniscus angle of safranine solution with cell walls were the prime factors for the variation of liquid flow speed in wood. Vessel was found to facilitate prime role in longitudinal penetration for hardwood species. The penetration depth in vessel of G. arborea was found highest among all vessels. Anatomical features like ray parenchyma cell length and diameter, end-wall pits number were found also responsible fluid flow differences. Initially liquid penetration speed was high and the nit gradually decreased in an uneven rate. Liquid flow was captured via video and the penetration depths in those cells were measured. It was found that even in presence of abundant rays in hardwood species, penetration depth of liquid in radial direction of softwood species was found high. Herein the ray length, lumen area, end wall pit diameter determined the radial permeability. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Following a go-stop-go cycle, the penetration speed of a liquid decreased over time.

• Journal of the Korean Wood Science and Technology
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• 제47권4호
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• pp.509-518
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• 2019

This study analyzed the effect of organic solvent extractives on the classification of wood species via near-infrared spectroscopy (NIR). In our previous research, five species of Korean softwood were classified into three groups (i.e., Cryptomeria japonica (cedar)/Chamaecyparis obtuse (cypress), Pinus densiflora (red pine)/Pinus koraiensis (Korean pine), and Larix kaempferi (Larch)) using an NIR-based principal component analysis method. Similar tendencies of extractive distribution were observed among the three groups in that study. Therefore, in this study, we qualitatively analyzed extractives extracted by an organic solvent and analyzed the NIR spectra in terms of the extractives' chemical structure and band assignment to determine their effect in more detail. Cedar/cypress showed a similar NIR spectra patterns by removing the extractives at 1695, 1724, and 2291 nm. D-pinitol, which was detected in cedar, contributed to that wavelength. Red pine/Korean pine showed spectra changes at 1616, 1695, 1681, 1705, 1724, 1731, 1765, 1780, and 2300 nm. Diterpenoids and fatty acid, which have a carboxylic group and an aliphatic double bond, contributed to that wavelength. Larch showed a catechin peak in gas chromatography and mass spectroscopy analysis, but it exhibited very small NIR spectra changes. The aromatic bond in larch seemed to have low sensitivity because of the 1st overtone of the O-H bond of the sawdust cellulose. The three groups sorted via NIR spectroscopy in the previous research showed quite different compositions of extractives, in accordance with the NIR band assignment. Thus, organic solvent extractives are expected to affect the classification of wood species using NIR spectroscopy.

• 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

조선후기 국용목재에 사용된 수종을 파악하기 위하여 영건의궤 조선후기 11종의 영건에 명시된 수종을 분석하였다. 주요 용도로는 궁궐, 제실, 사묘, 성곽의 수리와 보수 공사에 사용된 것으로 파악되었다. 17세기~20세기 영건의궤에 명시된 수종 중 활엽수재로는 가래나무, 느티나무, 물푸레나무, 박달나무, 오동나무, 참나무류(갈참나무, 굴참나무, 떡갈나무, 상수리나무, 신갈나무, 졸참나무)가 확인되었으며, 침엽수재로는 소나무와 잣나무가 확인되었다. 문화재를 수리할 때에는 동일 수종을 원칙으로 하기 때문에 수종 조사는 중요한 부분이다. 각 수종에 대한 목재해부학적 이미지는 실제 사용된 목부재를 대신해서 국립산림과학원 목재표본실에 소장 되어있는 같은 수종 재감을 활용하였다. 조선후기 영건의궤 편역본을 통하여 목조문화재 건축물에 사용된 주요 수종을 알 수 있었으며, 수리·보수 시 사용될 목재 수종을 판정하는 데 필요한 목재해부학적 이미지를 마련하였다.

• 한국습지학회지
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• 제17권2호
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• pp.124-129
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• 2015

하천의 복원을 위한 기초자료로 사용하고자 인간의 간섭에 의한 훼손이 없거나 적은 10개의 자연하천을 군집생태학적 방법으로 조사하여 통계적으로 분석하였다. 그 결과 신갈나무군락과 소나무군락, 사시나무군락, 굴참나무군락, 산벚나무군락 등 총 29개의 식물군락으로 확인되었다. 하천식생은 계곡 계반림과 하변림으로 나누어졌다. 계곡 계반림은 경사가 급하고 물에 의한 영향이 적어 경목림이 우점하였고, 하변 연목림은 버드나무류로 대변되었다. 하천 선택시 자연성이 기준이 되어 인간의 간섭이 많은 하류보다 중 상류에 위치한 조사지가 많았고, 그에 따라 출현군락의 92%(44 plot)는 경목림이었고, 8%(4 plot)는 연목림이었다. 전층을 이용한 PCA 분석에서는 신갈나무군락 그룹과 산벚나무군락 그룹, 소나무군락 그룹, 산벚나무군락과 소나무군락 혼합 그룹, 기타군락 그룹으로 크게 5개의 그룹으로 나누어졌다. 교목층을 이용한 PCA 분석은 신갈나무군락 그룹, 산벚나무군락 그룹, 기타군락 그룹으로 크게 3개의 그룹으로 나누어졌다. 하천변에 출현한 식물군락은 경목림과 연목림으로 나누어졌으며, 이를 통해 하천제방권 및 고수위권은 신갈나무, 소나무, 사시나무, 굴참나무와 산벚나무 등의 종을 식재하는 것이 적합하고, 고수부지권 및 저수위권은 버드나무속 식물을 식재하는 것이 적합할 것으로 판단된다. 식재될 목본에 따른 초본의 선택은 통계분석에서 같은 그룹에 속해있고, 높은 빈도로 출현하는 종으로 하는 것이 적합하다고 판단된다.