• Title/Summary/Keyword: hardwood

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Color Grading of Hardwood Dimension Parts with Color Computer Vision (칼라 컴퓨터시각을 이용(利用)한 활엽수(闊葉樹) 부재(部材)의 색(色)에 의한 선별(選別))

  • Yoo, S.N.;Krutz, Gary W.
    • Journal of Biosystems Engineering
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    • v.18 no.3
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    • pp.288-295
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    • 1993
  • 본 연구는 칼라 컴퓨터시각을 이용하여 가구에 이용되고 있는 활엽수 부재의 색에 의한 선별법을 제시하고자 수행되었다. 붉은 오우크 가구 부재를 대상으로 칼라 컴퓨터시각 시스템을 이용 화상을 얻은후 R,G,B 농도값을 근거로 나무결, 나무결함, 3가지의 색깔 즉 핑크색, 흰색, 갈색의 나무부분, 이밖에 배경에 대한 지식 베이스화를 행하여 각 부재에 대하여 이들의 비율을 quadratic Bayes classifier를 이용 구하였으며, 이 중 나무결, 나무결함, 배경을 제외한 3가지 색상에 대하여 부재가 갖는 상대적인 비율을 근거로 qadratic Bayes classifier와 neural network를 각각 이용하여 핑크색, 흰색, 갈색의 3가지 부재로 구분하였다. 선별의 정확도는 기존의 육안에 의한 선별을 기준으로 비교하였는데 qadratic Bayes classifier에 의한 선별이 91.7%, neural network을 이용한 선별이 96.7%의 높은 정확도를 보였다. 따라서 가구의 품질향상을 위한 색에 의한 부재 선별에 칼라 컴퓨터시각이 유용하게 이용될 수 있을 것으로 판단되었다.

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Chemical characteristics of Compound middle lamella lignin (복합 세포간층 Lignin의 화학적 성상)

  • Eom, Tae Jin
    • Current Research on Agriculture and Life Sciences
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    • v.9
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    • pp.103-108
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    • 1991
  • The chemical characteristics of lignin in the differentiating xylem were investigated and compared with those of mature-wood. The compound middle lamella lignin deposited in the early stage of lignification of cell walls in the softwood(Larch) as well as the hardwood(Birch) was confirmed to be the so-called guaiacyl-type lignin and was found to have a relatively larger content of phenoxy hydroxyl group as terminal units and to be more abundant in condensed-type structures like as phenylcoumaran structures compared with mature-wood lingin.

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The Isolation of D-Xylose from Hardwood and it's Fermentation to Ethanol by Yeasts (활엽수로부터 D-xylose의 분리 및 에탄올 생산)

  • Paik, Ki-Hyon
    • Journal of the Korean Wood Science and Technology
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    • v.19 no.2
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    • pp.3-13
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    • 1991
  • D-xylose 는 임산 바이오마스의 화학석 조성분 증 셀룰로오스와 리그닌 다음으로 가장 많이 존재하는 성분이다. 그럼에도 불구하고 D-glucose만큼의 연구가 진행되지 못해왔다. 단지 xylitol, furfural 및 xylonic acids탐의 몇가지 산으로 전환시켜 이용될 뿐이다. 이런 이유는 D-xylose를 공업적으로 다량 추출하는 방법과, 특히 정선 방법에 어려운 문제점이 있기 때문이다. 그러므로 본 총설에서는 D-xylose를 보다 경제적으로 분리하는 방법과 D-xylose를 에탄올로 발효시키는 과정중의 제 문제점들에 관해 기존에 발표된 논문들을 정리하고저 한다. 즉 공업적으로 D-xylose를 다량 분리시키는 방법으로서 해섬/추출 폭쇄/추출, 초산펄핑, 전기가수분해 방법들이 논의 되었으며, 분리된 D-xylose를 에탄올로 발효시킬 경우 D-xylose의 대사, 발효 조건들의 영향, 헤미셀룰로오스 가수분해물의 발효, 발효의 전망과 문제점등이 포함되었다.

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Wood Identification of Neolithic Charcoals Excavated at Giheung Nongseori Ruins (기흥 농서리유적에서 발굴된 신석기시대 목탄의 목재 식별)

  • Eom, Young-Geun;Xu, Guang Zhu
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.4
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    • pp.275-281
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    • 2010
  • Wood identification was conducted for the 8 Neolithic charcoals excavated at Giheung Nongseori Ruins through scanning electron microscopy. They were all identified as hardwood: 6 and 1 were found to be Prinus section and Cerris section of subgenus Lepidobalanus under genus Quercus, respectively, and the remaining 1 to be genus Betula. This species composition was thought to indicate the temperate to warm temperate climate region.

Manufacture of Reconstituent Tobacco Sheet from Residual Tobacco Stalks (담배줄기 펄프를 이용한 판상엽 제조)

  • 조남석
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.4
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    • pp.93-97
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    • 1999
  • Tobacco stalks are greatly produced as annual agricultural wastes. These residues are available approximately 70,000 tons per year. This study was performed to evaluate the potentials of tobacco stalks as a new resource for reconstituent tobacco sheet. Tobacco stalk was more lignified than cereal straws, and had similar chemical constituents to hardwood. Pulping yields by cooling at 170$^{\circ}C$ of dry and green tobacco stalks were 56.7% and 66.3% , respectively. Around 50$^{\circ}$SR freeness level of mixed pulp was adjusted by mixing more than 10% chemical pulp9CP) in the case of dry tobacco stalk and more than 15% CP with wet one. By immersing this handsheet in extracted cooking liquors, reconsitutent sheet contained about 0.28% of nicotines could be prepared. This sheet had enough strength properties for cigarette paper making . In conclusion, it was proved that tobacco stalk could be used to produce the reconstituent tobacco sheet.

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A study on the Process Improvement of Papermade Reconstituted Tobacco (제지식 판상엽의 공정 개선 연구)

  • 김영호;한영림;김근수;김대종
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.2
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    • pp.164-169
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    • 2000
  • The reconstituted tobacco leaves(RTL) playa major part in the control of the low density and tar cigarette. Reconstituted tobacco manufactured by the papermaking process has much higher filling power than homogenized tobacco manufactured by slurry and rolling process. Fragile reconstituted tobaccos are liable to lead to small particles detrimental for filling power so they must be properly flexible. This work was conducted to determine the effect of CaCO$_3$ addition in paper-making process on the filling power and the flexibility of the reconstituted tobacco and to obtain the fundamental informations for improving the quality of domestic reconstituted tobacco. We analyzed the wood fiber species, the filler level, the fiber length, the fineness level and observed the surface of the RTL. From the obtained results, we could determine that foreign reconstituted tobacco was manufactured by blending softwood with hardwood and over 8% of calcium carbonate at the addition level. The domestic RTL has much higher fine fiber level by 23.2 % than that of foreign, so the refining treatment process and the condition must be reoptimized for the improvement of RTL quality.

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Flame-resistant treatment schedule of Microwave drying wood (마이크로웨이브 건조목재의 방염처리 스케줄)

  • Park, Cheul-Woo;Her, Jae-Won;Lim, Nam-Gi
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.27-28
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    • 2011
  • This research aims to secure fundamental data for the development offire-retardant wood by soaking dried wood in fire-retardant liquid. To dry wood, optimal drying conditions for softwood usually used as structural material and hardwood usually used as finishing or furniture material were derived by varying the microwave outputs and heating times of microwave wood drying equipment. The research foundthat each specimen needs 8 to 15 minutes of heating time depending on water content and output. For softwood, fire-retardant liquid equivalent to about 10 percent of the total mass of the specimen infiltrated into the dried wood, of which the water content was reduced to 5~6 percent.

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Ultrastructural Description of Some Wood Degrading Fungi at Light Microscopic and Scanning Electron Microscopic Levels (전자현미경 수준에서의 목재부후균의 미세구조학적 고찰)

  • Lee, Yang-Soo
    • Applied Microscopy
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    • v.34 no.4
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    • pp.271-276
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    • 2004
  • The genus of Biscogniauxia, well known wood degrading fungi, is a member of the Xylariales, which has woody to carbonaceous, brown to dark brown stromata. Daldinia concentrica and Biscogniauxia sp. isolated from heavily decayed hardwood, are precisely described under light microscopic and scanning electron microscopic level. Daldinia concentrica will be the first ultrastructural description in Korea. The unidentified species collected, having small size of ascospores $11.4\;15.6{\times}9.6\;12.0{\mu}m$ with full germ slit, are taxono-mically compared with similar species found in Korea.

Pore Structure and Reflectivity of Light of Paper

  • Won, Jong-Myoung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.3 s.116
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    • pp.7-12
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    • 2006
  • The pore structure of paper was modified by the application of the blending of pulp, refining, and filler particle size and ash content. It was conformed that the reflectivity of paper can be modified by the combination of the above parameters. It was also found that the change of reflectivity of paper was greatly dependent on the pore structure, such as average pore size, pore size distribution and porosity. The average pore size was decreased with addition of HwBKP, but the smallest average pore size was obtained from the addition of 80% HwBKP Refining of pulp decreased both average pore size and the reflectivity of paper. The pore size distribution of filled paper can be varied by the combination of filler particle size and ash content

Effects of Recycling on Adsorption Characteristics of Cationic Polyacrylamide onto Primary and Secondary Fines (리사이클링 횟수에 따른 일차미세섬유와 이차미세섬유의 폴리아크릴아미드 흡착특성 변화)

  • 주성범;이학래
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.2
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    • pp.34-41
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    • 1999
  • Adsorption of cationic polyacrylamide dry strength resins onto the surface of papermaking fibers and fines is critical for their effective utilization. Since dry strength resins are frequently employed when recycled fibers containing a great deal of fines are used as a raw material, their adsorption characteristic onto the recycled fiber fines is of great importance. In this study, effects of recycling on adsorption characteristics of cationic polyacrylamide onto primary and secondary fines were examined. Never dried bleached hardwood kraft pulp was beaten and dried for recycling. In each recycling step the adsorption characteristic of a cationic PAM onto primary and secondary fines was evaluated by kjeldahl nitrogen analysis method. The influence of recycling on water retention value and carboxyl content along with the sheet density and tensile strength was examined. Secondary fines of never dried pulp adsorbed twice as much of C-PAM as the primary fines, however, the adsorption capacity of the secondary fines decreased rapidly during the course of recycling and showed lower adsorption capacily than primary fines.

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