• 생명과학회지
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• 제13권5호
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• pp.618-625
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• 2003

목재 저장소의 토양에서 분리된 호열성 세균인 Paenibacillus sp. DG-22로부터 xylanase를 생산하기 위한 배양조건을 최적화시키기 위해 연구를 수행하였다. Xylanase생산은 세포의 생장과 연관된 양상을 나타내었다. Xylanase 활성은 배양상청액에서만 발견된 반면 $\beta-xylosidase$활성은 주로 세포와 결합되어 있었다. Xylanase활성의 형성은 자일란에 의해 유도되었고 포도당과 자일로스에 의해서 억제되었다. 여러 상업적 자일란을 이용하여 xylanase의 생산양상을 조사한 결과 0.1-0.5%의 birchwood xylan에서 가장 높은 생산율을 나타내었다. 조사된 여러 질소 원들 중 효모추출물이 xylanase생산을 위하여 최적이었다. xylanase의 활성은 $Co^{2+},\; Cu^{2+},\; Fe^{3+},\; Hg^{2+}\;$ 와$\; Mn^{2+}$ 이온들에 의하여 억제된 반면 $Ca^{2+},\; Mg^{2+},\; Ni^{2+},\; Zn^{2+}$ 이온들과 DTT에 의해서는 촉진되었다. 수은은 5 mM의 농도에서 xylanase 활성을 완전히 파괴하였다. 자일란 가수분해의 주된 산물은 자일로바이오스, 자일로트라이오스 그리고 자일로 올리고당이었고 이것은 이 효소가 endoxylanase라는 것을 나타낸다.

• 한국가구학회지
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• 제25권1호
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• pp.45-54
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• 2014

Wood cutting utilizing CNC art in the field of furniture design industry, art, education are diverse. However, there is lack of data in the case for wood cutting, such as cutting conditions and wood cutting. So this article is to establish furniture design processing using CNC. The researchers investigated the processed products using CNC, the data of the web site and CNC relevant articles, then organized its impact on the furniture industry today. History and definition of CNC have studied for a discussion of the advantages and disadvantages. Then, the researchers analyzed the cases to investigate the wood cutting conditions, was applied to the fabrication of furniture domestic and foreign. CNC organized systematically design information through the computer So, it allowed to reduce the repetitive behavior that has to work hand in the furniture manufacture existing. CNC has made it possible to design a fine complex in furniture design industry. So it became possible to make a new representation and production of various forms. Material about CNC are mostly for milling machine and shelves for metal processing. So, the researchers investigated and precautions general content of wood cutting. The enhanced understanding to investigate an example that is applied outside the country, is used to analyze the expression various techniques CNC. It is difficult to obtain accurate data processing, it has various characteristics in the same timber, Future research is about analyzing type applications and CNC machining range at the time of processing the various wood.

• 한국환경복원기술학회지
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• 제18권1호
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• pp.103-113
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• 2015

Korean pines(Pinus koraiensis) are one of the major plantation species in the Republic of Korea and their natural habitats range from Japan and China to Siberia. The seed of Korean pines, pine nuts, are well know for good food reserves. Due to the global changes which drive the Korean peninsula into the semi-tropical climate, current plantations and natural habitats of Korean pines are faced with the change in the environmental conditions to some extent. To anticipate suitable sites for Korean pines in the future, the location of Korean pines were extracted from the 'Map of suitable trees on a site' that provides the map of suitable trees on a site considering tree species for timber and special uses, and then MaxEnt modelling was used for generating a prediction map on the basis of statistical analysis. As a result, the order of predicted suitable sites were Kangwon-do, Kyungsangbuk-do and Chungcheongbuk-do provinces and sites with high elevation within those provinces were considered most suitable in common. The prediction map of suitable sites for Korean pines presented that suitable sites in the future decreased by 72.2% by 2050's and almost disappeared with a decrease of 92.1% by 2070's on a nationwide scale. In relation to the major production regions of pine nuts in South Korea - Gapyung gun and Yangpyung gun, Kyunggi province and Hongcheon gun, Kangwon province, suitable sites within their areas were predicted to increase by 2050's but become extinct in South Korea by 2070's. To establish a long-term countermeasures against the improvement on forest productivity quality in terms of managing national food security, the result from this study can be considered as a firm basis of predicting plantation suitability. Also, it can be used to predict the changes in supply of forest products and thereby market values in accordance with climate change scenarios.

• 펄프종이기술
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• 제43권3호
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• pp.59-65
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• 2011

The saw dust of tropical hardwood, Nyatoh(Palaquium Spp.), was used as a raw material for the preparation of the high valued microcrystalline cellulose(MCC). Three pulping methods, soda pulping, Kraft pulping, and acid-sulfite pulping were applied to obtain cellulose from the saw dust. The residual impurities were removed with the additional bleaching processes: (A) $ClO_2{\rightarrow}H_2O_2$; (B) $ClO_2{\rightarrow}O_3$; (C) $O_3$. For the acid treatment for MCC preparation, the $H_2SO_4$, with three concentration, 20%, 40%, 60% were applied and the effects of $H_2SO_4$ concentration on the properties of MCC were evaluated. The results indicated that the MCC obtained by acid-sulfite pulping followed with $O_3$ treatment and 40% $H_2SO_4$ treatment showed less residual lignin, higher brightness and crystallinity than that of Avicel MCC.

• Journal of the Korean Wood Science and Technology
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• 제25권1호
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• pp.42-49
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• 1997

The purpose of this study was to investigate the relationships among density, moisture content, and modulus of elasticity in which are important characteristics in physical and mechanical properties of woods. In this study, the dynamic MOE was calculated through the combination with resonance frequency of transverse vibration method and density, and the estimated moisture contents were calculated with two different equations (1, 2) in order to compare with experimental moisture contents. The following results from this study were obtained: 1. According to the regression analysis with two different parameters (E and density), the two regression lines appeared to be straight intersecting at 0.6 density. As another factor, moisture contents in wood also influenced on the analysing regression at the below F.S.P. 2. When considering the relationship between moisture contents and E, the tendency of each moisture content and E showed very similar pattern suggesting that moisture contents in addition to density are very important parameter. 3. When together with moisture contents and density as parameters for multiple regression analysis, coefficiences of determinations are dramatically improved. Interestingly, the coefficiences of determinations are further increased when analysing at the below point of F.S.P. and when analysing higher and lower density separately. In summary, more correct estimation of the dynamic MOE of woods can be possible with only transverse vibration and density in wood. Therefore, with this indirect method, the calculation of MOE in all kinds of woods including timber, live tree and wood products can be feasible resulting in accelerating the efficiency of time and labor.

• 한국농림기상학회지
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• 제7권4호
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• pp.258-264
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• 2005

The objectives of this study were to study 1) emergence of pine bark beetles, 2) larval density in residual timber on Idlest land by each felling season, and 3) the secondary damage rates in the tended forest. Pine forest land which had undergone tending had a higher secondary damage ratio $(59.6\%)$ by pine bark beetles than forest land that was not tended $(2.8\%)$. The number of escape holes averaged 11.3 0.31 per $250 cm^2$ on the bark of leaf trees in the tended forest. The number of escape holes was higher in the Jinju site than in the Hamyang site. The larval habitat density of pine bark beetles as compared with each felling period was higher after mid-October than in forests tended early in October. Thus, forests should be tended before early October in order to prevent secondary damage from pine bark beetles. Secondary damage in the tended forest was higher in the upper part $(75.5\%)$ of the tree crown than in the lower part $(49.2\%)$. The damage was higher in terminal shoots $(80\%)$ than in lateral shoots $(48\%)$. Therefore, secondary damage by pine bark beetles can cause deterioration of the elongation growth of the forest trees. In conclusion, if by-products of tended pine forest forests are neglected, they will be utilized as a propagation site for pine bark beetles (Blastophagus piniperda L). The propagated adults will damage the tender shoots of the leaf trees and thus seriously limittheir elongation.

• Journal of the Korean Wood Science and Technology
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• 제43권1호
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• pp.36-42
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• 2015

국산재에 대한 전단탄성계수와 실질탄성계수를 구하기 위해 서로 다른 세장비에 대한 휨강도실험 및 응력파실험을 실시했다. 국산재의 휨 성질들은 12%로 조습 처리된 무결점 시편으로 측정하였다. 휨강도와 탄성계수는 세장비(L/D)에 영향을 받아 세장비가 증가하면 증가하였다. 전단탄성계수(G)와 실질탄성계수는 서로 다른 세장비에 대한 휨강도 실험 및 응력파실험의 결과를 이용하여 계산했고, 그 값들은 국산재가 구조용도로 사용된다면 유용할 것이다. 하지만 이들 결과들은 제한된 수의 시편들에 대한 값으로 이들 수종의 실질 평균값을 나타내진 않는다.

• Journal of Forest and Environmental Science
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• 제29권2호
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• pp.147-156
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• 2013

Multiple use forestry is capable of generating income for forest based communities through Non-Timber forest products (NTFPs) which provide food, medicine, materials for domestic use and cash income for communities adjoining forest areas in developing countries. This study evaluates the economics of producing ginger rhizomes under teak canopy in a multiple land use system during 2007 and 2008 in even aged teak plantations in Ibadan and Ife, Nigeria. Twelve $6m^2$ sample plots were randomly selected in Completely Randomized Block Design within and outside the plantation. Average ginger rhizome of (50-60 g) were planted on the slightly tilled soil. NPK 15:15:15 was applied at 180 kg/ha on a split unit dose. ANOVA, Profitability, Benefit-Cost (B/C) ratio were used to analyze data. Results showed no significant differences between sites in ginger rhizome yield, (0.089 and 0.718, ${\rho}{\leq}0.05$) in 2007 and 2008 respectively. Average yield were higher outside teak canopy in both sites and treatments, (Ibadan -40.05 g>32.9 g, Ife -67.6 g>25.2 g and Ibadan -41.3 g>31.5 g, Ife -66.8 g>25.0 g) with and without NPK respectively. NPK had no effect on yields within teak plantation, (Ibadan -31.5<32.9 g, Ife -25 g<25.2 g). Ginger rhizome production was viable financially without inorganic fertilizer during second cropping season within and outside plantation (B/C=1.02, 1.09) respectively. Ginger could be raised profitably under teak canopy, however, studies on insolation requirement of ginger under teak canopy and other tree plantations are recommended.

• 한국산림과학회지
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• 제103권1호
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• pp.122-128
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• 2014

본 연구는 산마늘 노지재배와 임간재배의 수익성 차이를 비교 분석하고, 산마늘 임간재배가 앞으로 나가야할 방향을 제시하고자 수행되었다. 강원도, 충북, 전남, 경북지역에서 12명의 산마늘 재배자를 대상으로 작업공정별 투입인력 및 비용 등에 관해 심층면접설문조사를 실시하였다. 그 결과를 바탕으로 수익성 분석기법인 IRR, B/C ratio, NPV를 이용해 투자수익성을 분석하였다. 임간재배 산마늘의 판매가격 25,000원/kg과 노지재배 산마늘의 판매가격 15,000원/kg을 적용하여 분석한 결과 각각 IRR 36.2%과 54.2%로 나타나 산마늘 노지재배의 수익성이 더 큰 것으로 분석되었다. 산마늘 임간재배의 수익성이 다른 산림단기소득작물과 비교해도 결코 낮은 수준이 아니며, 집약재배를 위한 기술개발이 뒷받침된다면 노지재배 못지않게 높은 수익을 올릴 수 있을 것이다.

• 한국산림과학회지
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• 제106권4호
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• pp.487-496
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• 2017

사회주의 계획경제 체제를 유지해오던 북한 내에 시장이 합법적인 공간으로 작동하면서 북한경제의 시장화 현상이 급격하게 확산되고 있다. 북한의 시장화 확산은 북한의 산림부문과 주민들의 산림소토지(뙈기밭) 이용에도 영향을 미치고 있다. 본 연구는 북한에서 발행하는 공식문헌과 북한의 시장화 확산에 관한 국내 관련 자료들을 검토하여 최근의 북한 경제체제 변화와 시장화 확산 현상이 산림관리에 미치는 영향을 분석하고 이에 걸맞은 대북 산림복구 지원 전략을 제시하고자 하였다. 김정은 정권은 시장경제 운영 방식을 대폭 수용한 '우리식의 새로운 경제관리 방법'을 제시하면서, 개인에게 생산물 처분권을 보장하는 포전담당제를 도입하고 외부투자를 유치하기 위한 경제개발구를 설치하는 등 시장화 확산에 따른 정책과 제도를 마련하여 추진하고 있다. 김정은 정권은 2012년 전국 황폐산림의 10년 내 산림녹화 달성을 목표로 내세우고, 경사지 경작지인 뙈기밭 회수조치를 실행하는 등 산림복구를 강력하게 추진하려는 정책의지를 제시하였다. 그러나 시장화가 확산되면서 목재수요 증가에 따른 벌채증가, 불법 땔감 채취와 판매, 생계용 임산물 채취, 식량판매를 위한 불법경작 등이 더욱 확대됨에 따라 일방적인 군중동원형 산림복구로는 한계에 봉착할 것으로 전망된다. 이에 북한당국도 경사지 산림황폐지에 나무를 심고 이에 대한 보상으로 경작권과 생산물 처분권을 허용하는 임농복합경영 방식을 도입하고, 10개년 임농복합경영전략 및 행동계획('15~'24)을 수립하는 등 시장친화적 산림정책 실행을 시도하고 있다. 따라서 앞으로 남한의 대북 산림복구 지원방식도 과거와 달리 물자나 기자재 위주의 지원방식에서 벗어나 협동농장 단위 임농복합경영의 주민 공동 사업화 방안, 개인 소토지의 산림 소득원화 지원방안, 산림사업을 활용한 산촌종합개발특구 활성화 방안 등 북한주민 공동체가 참여할 수 있는 지원모델을 마련하여 북한의 시장화 확산 및 산림정책 변화와 연계한 실효성 있는 대북 산림복구 지원전략을 구사할 필요가 있다.