• Journal of the Korean Wood Science and Technology
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• 제16권4호
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• pp.54-60
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• 1988

Machinabilities means inherent properties of pinus densiflora at Chunyang district to be CNC machined easily or not, and processing abilities of the tool and machine together. This explanation signifies that machinabilities have two phases of signification, depended on considering and stress either materials or tools preferentially. This paper discuss machinabilities, the following items are usually employed as the indices of stress distribution at the cutting tool rake face. The stress distributions on the chip - tool contact surface at the early stage of the chip forming and under the stage of fringe pattern in wood cutting were analyzed the photoelastic method. The tool used in the present experiment was the special cutting tool H.S.S. one made in laboratory. And isochromatic fringe pattern and isolinic line of work piece by chip-behavior during the cutting operation were photographed with the feed camera continuously. The effects on the stress, distribution on the rake face of the epoxy tool and the strain distribution in the work piece of wood plate by chip behavior are cleared in pre cent experiment.

• Journal of the Korean Wood Science and Technology
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• 제16권4호
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• pp.61-69
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• 1988

Recently the automization of wood manufacturing and the development of CNC machine tools becomes the center of interest. Cutting mechanism, tool wear and the roughness of machined surface have been studied. In the studies about wood for special uses, concrete data of cutting is desired. While Pinus densiflora is characterized that heartwood develops as age increases, Chunyang District has the characteristic of strength, red color, relatively regular chap and high heartwood - percentage. But there is no data about cutting this wood, Chunyang District. In this study face milling by sintered carbide tool was excuted to Chunyang District. Cutting force, Surface roughness and states were investigated with regard to cutting speed. Example results were as follows; 1) Mean cutting resistance against lateral component force and longitudinal component force decreased rapidly up to cutting speed of 155 m/min, and remains constant above this speed. 2) The surface roughness of cutting surface lowered as cutting speed increased, regardless of fiber formation. Radial rougness of fiber is larger than lineal surface roughness. 3) Increase in Cutting speed made machining mark restrained. Down-milling showed larger marks than up-milling.

• Journal of Ecology and Environment
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• 제30권4호
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• pp.331-340
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• 2007

We examined the evolutionary and ecological processes shaping current geographical distributions of a Korean wood-eating cockroach species, Cryptocercus kyebangensis. Our research aims were to understand evolutionary pattern of DNA sequences, to construct genetic network of Cryptocercus kyebangensis local populations and to understand evolutionary and ecological processes shaping their current geographical distribution patterns via DNA sequence information and genetic networks, using sequence data of two genes (ITS-2 and AT region) from local populations of C. kyebangensis. The results suggest that the ITS-2 and AT region are appropriate molecular markers for elucidating C. kyebangensis geographic patterns at the population level. The MSN-A based on the ITS-2 showed two possible routes, the Hwaak-san and Myeongji-san route and the Seorak-san and Gyebang-san route, for migration of ancestral C. kyebangensis into South Korea. The MSNs (MSN-A and -B) elucidate migration routes well within South Korea, especially the route of Group I and Group II.

• 한국화재소방학회논문지
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• 제34권4호
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• pp.13-21
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• 2020

본 연구에서는 건축내장용 합판류 목재를 대상으로 목재의 두께별 다양한 입사열유속에 따른 연소특성 측정 실험을 수행하였으며, 측정한 연소특성은 EHC, HRR peak 및 도달시간, MARHE, 인화온도이다. 실험에 사용된 목재 시편은 4.8~18 mm 두께, 목재 시편에 유입되는 입사열유속은 25, 35, 50 및 60 kW/㎡을 적용하였으며, 목재 시편의 종류는 MDF 2종, 파티클 보드, 일반 합판이다. 종합적인 비교를 통하여 연소특성별 각각의 목재에 해당하는 화재패턴을 분석하여 화재에 대한 위험성을 검토하였다. 파티클 보드의 경우 화재 위험성이 높게 나타났으며, 제시한 연소특성 정량화 결과는 복합 가연물의 화재하중 산정에 중요한 입력 요소로 기여될 수 있다.

• 한국균학회지
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• 제41권4호
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• pp.236-242
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• 2013

꽃송이버섯(Sparassis crispa)은 배양과정에서 항균물질인 sparassol, methyl orsellinate (ScI)와 methyl-dihydroxy-methoxy-methylbenzoate (ScII) 등의 화합물을 생산하는 것으로 알려져 있으며, 이 중 ScI와 ScII는 sparassol보다 높은 항균활성을 나타내는 것으로 보고되었다. 본 연구에서는 꽃송이버섯의 액체배양 시 균사체가 생산하는 항균 물질인 methy1 orsellinate와 sparassol을 분리하여 NMR과 ESI-MS 분석을 통해 그 구조를 동정하였으며, HPLC 분석을 통해 methy1 orsellinate와 sparassol의 retention time은 각각 15분과 31분임을 확인하였다. S. latifolia의 화합물 생산 양상은 크게 4가지로 대별되며, 균주에 따라 다르게 나타났다. 기주식물과의 상관관계를 분석한 결과, 일본잎갈나무와 잣나무에서 분리된 균주는 서로 다른 생산 양상을 보인 반면, 소나무와 전나무에서 분리된 균주는 동일한 생산 양상을 나타냈다. 균체량과 화합물 생산량과의 상관관계는 나타나지 않았다. Methy1 orsellinate 생산량은 낙엽송에서 분리된 KFRI 645 균주가 0.170 mg/ml로 가장 높았으며, sparassol 생산량은 소나무에서 분리된 KFRI 747 균주가 0.004 mg/ml로 가장 높았다. 이러한 결과를 통해 꽃송이버섯 균주들의 methyl orsellinate와 sparassol의 생산 양상은 기주식물의 종류에 따라 다르다는 사실을 확인하였다.

• Journal of the Korean Wood Science and Technology
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• 제33권5호통권133호
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• pp.1-6
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• 2005

The anatomical structure of fusiform ray was examined by scanning electron microscopy (and microscopic images were analysed by image analyser) to explain the differences in radial fluid uptake between the extremes in the radial treatment data, i.e. between the selected trees of QCI (Queen Charlotte Islands in Rhondda, South Wales) and SO (South Oregon in Dalby, North-East England) planted in the UK. The ray structure of these two seed origins was examined microscopically and different patterns of ray composition were observed. The most important anatomical features influencing radial permeability were the nature of fusiform ray, and the condition of the resin canals, epithelial cells and intercellular spaces in particular.

• 한국가구학회지
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• 제25권3호
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• pp.198-204
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• 2014

Aggravation of natural environment, improvements in income, internet diffusion, spread of five-day work a week, and population aging seem very different from each other. However they boil down to consumption. These culture patterns are changing into environment-friendly and productive housing culture. In other words, people might tend to have frequent contacts with not only environment-friendly housing in bustling cities but also woods that is environment friendly materials in their leisure time. In the period of people young and old alike are in favor of woodcrafts, this study was conducted for giving information to who speicalized in woodcrafts. Furthermore, the study shows that other countries also added grain and figure to woodcrafts for visually appealing.

• 한국생활과학회지
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• 제15권2호
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• pp.303-316
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• 2006

The present study deals with developing a new modem design of quilt which is characteristic of Korean traditional patterns. The goal of this study is to make some samples of the pattern as a basic motive of quilt work by using some Korean traditional patterns that could be found in roof tiles, windows, Neung-Hwa (a kind of wood cut for printing book covers), and others. This study examines the concept of quilts, their historical background, and their characteristics. This study also examines traditional patterns that are applicable to the patchy work of quilt, discussing the characteristic of both the Korean patterns and Nubi (Korean traditional quilt). In the process of pattern development, the original patterns were simplified and transformed to apply them to the modem quilt pattern. Fabrics (100% cotton) of similar colors were used to emphasize quilting lines. This study has found followings; 1) The geometric pattern usually consists of dots, lines, and faces. These patterns are suitable for pieced quilts. 2) The curvilinear pattern found in roof tiles or Yi-Dynasty coins, can be easily re-expressed by the applique technique. Combinations of fabrics and motive compositions can express quilts in realistic and creative ways. 3) Addition of Korean traditional quilt techniques, such as parallel lines or swastika stitches, to the traditional object-derived quilt patterns led to the creation of images close to the already existing Korean quilt, Nubi.

• Journal of the Korean Wood Science and Technology
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• 제28권2호
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• pp.19-24
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• 2000

본 논문에서는 목재시편의 횡단연적과 수분경사가 라디에타파인 심재와 번재의 초음파 전달속도에 미치는 효과를 조사하였다. 각 수분경사 모델시편은 함수율이 다른 다섯 개의 소편을 배합하여 만들었다. 횡단면적이 작아질수록 초음파 전달속도는 심재와 변재 모두 4~8% 감소하였다. 수분경사 모델시편을 투과한 초음파 신호를 분석한 결과, 횡단면적이 클수록 저주파 신호가 고주파 신호보다 분명한 주류률 이루었다. 평균 함수율이 같더라도 수분경사가 다르면 시편의 초음파 전달속도는 다르게 나타났다. 초음파 전달속도와 수분경사 모델시편의 내층 평균 함수율의 분포는 함수율에 따라 세 가지 서로 다른 형태를 나타냄이 밝혀졌다.

• 한국환경생태학회지
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• 제29권1호
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• pp.62-68
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• 2015

In order to get basic data for flood plain restoration, we surveyed the woody vegetation in Korean natural rivers and analyzed the species' characteristics with regards to patterns of richness and diversity. These characteristics were higher in hard wood forests than those in soft wood forests, such as Salix spp. community. Futhermore, they were the highest in the Prunus sargentii-Pinus densiflora community(H' 1.095), and the lowest in the Carpinus laxiflora community(H' 0.118) among the hard wood forests. Species' richness diversity were the highest in the Salix gracilistyla community, but the lowest in the S. koriyangi community or S. koreensis community among the soft wood forests. With regards to the dominant index, just one community is over 0.9, 13 communities are between 0.3-0.7 and 15 communities are less than 0.3. The Salix koreensis community was the highest at 0.931, and Prunus sargentii-Pinus densiflora community was the lowest at 0.13. Species' richness and diversity was significantly correlated with tree layer coverages and degree of slope. These results mean that in order to increase plant species diversity in flood plains planted hard woody trees, such as oaks and fir, are needed to suit environmental conditions with steeper slope and lower canopy coverage.