• 제목/요약/키워드: clear cutting

검색결과 105건 처리시간 0.031초

Effects of Weather Conditions on Sunburn in Stalk Curing of Burley Tobacco

  • Bae, Seong Kook;Jo, Chun Joon
    • 한국연초학회지
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    • 제22권2호
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    • pp.138-142
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    • 2000
  • The effects of stalk cutting time and environmental factors such as air temperature, leaf temperature, solar radiation and leaf moisture content during harvesting and curing in burley tobacco(Nicotiana tabacum L.) on weight loss of fresh stalks and sunburning in leaves were investigated at Chonju Experiment Station, Korea Ginseng & Tobacco Research Institute in 1996 and 1997. Twelve to fifteen percent of the fresh weight was lost in 3 to 4 hours after stalk-cutting, and sunburned leaves could be observed in case of stalk cutting between 11:00 and 15:00 O'clock on a clear sunny day, when the air temperature was 34 to 35$^{\circ}C$, leaf temperature 52 to 54$^{\circ}C$, and solar radiation 700 to 940 w/$m^2$. The leaves exposed to this weather condition were sunburned within 1 hour after stalk cutting. But low temperature (below $25^{\circ}C$) with high solar radiation(above 700w/m2) or high temperature(above 3$0^{\circ}C$) with low solar radiation (below 600w$m^2$) did not induce the sunburn damage in leaves. As the leaf temperature and leaf moisture content were higher, the sunburned leaves increased. The leaves at the higher stalk position were more easily sunburned than those at the lower. This result indicates that the immature leaves with higher chlorophyll content might be more susceptible to sunburning.

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ADHESION STRENGTH OF DIAMOND COATED WC-Co TOOLS USING MICROWAVE PLASMA CVD

  • Kiyama, Nobumichi;Sakamoto, Yukihiro;Takaya, Matsufumi
    • 한국표면공학회지
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    • 제29권5호
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    • pp.540-544
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    • 1996
  • To apply the CVD diamond film to coated tools, it is necessary to make adhesion strength between diamond film and substrate stronger. So adhesion strength of diamond coated WC-Co tools using Microwave Plasma CVD and cutting test of Al-18mass%Si alloy using diamond cutting tools were studied. Diamond coating was carried out using Microwave Plasma CVD apparatus. Reaction gas was used mixture of methane and hydrogen. Substrate temperature were varied from 673K to 1173K by control of microwave output power and reaction pressure. By observation of SEM, grain size became larger and larger as substrate temperature became higher and higher. Also all deposits were covered with clear diamond crystals. XRD results, the deposits were identified to cubic diamond. An analysis using Raman spectroscopy, the deposit synthesized at lower substrate temperature (673K) showed higher quality than deposit synthesized at higher substrate temperature (1173K). As a result of scratch adhesion strength test, from 873K to 1173K adhesion strength decreased by rising of substrate temperature. The deposit synthesized at 873K showed best adhesion strength. In the cutting test of Al-18mass%Si alloy using diamond coated tools and the surface machinability of Al-Si works turned with diamond coating tools which synthesized at 873K presented uniform roughness. Cutting performance of Al-18mass%Si alloys using diamond coated WC-Co tools related to the adhesion strength.

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뽕나무 유합촉진 고조삽목에 관한 연구 I. 발근촉진제 농도가 발근생장에 미치는 영향 (Hardwood Cutting with Callusing in the Mulberry(Morus bombycis Koidz.) I. Effect of a Root-Promoting Substance with Different Concentrations on Root Formation)

  • 최승운;김호락
    • 한국잠사곤충학회지
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    • 제33권2호
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    • pp.63-67
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    • 1991
  • 뽕나무(품종:신광뽕) 고조삽목에 있어서 삽수를 NAA 농도를 달리하여 2주간 유합촉진한 후 온실에 삽목한 경우 농도에 따른 발아 및 발근생장에 미치는 영향을 알기 위하여 시험한 결과는 다음과 같다. 1. 삽수동아의 발아생장은 NAA 농도가 높아짐에 EK라 삽목후 10일까지는 억제되어 지연되었다. 그러나 유합촉진 2주후에는 150ppmrn를 제외하고는 93% 이상 대부분 발아되었다. 2. NAA 농도별 발근은 삽목 15일 후 높은 농도에서 비교적 높은 발근율을 나타내었으며 이후 어느 농도에서나 증가하여 35일 후에는 매우 높은 농도(150ppm)에서 낙해발생으로 인한 다소 낮은 발근율을 제외하고는 그 이상 농도에서 100%의 발근율을 나타내었다. 3. 평균 뿌리길이는 농도가 높아짐에 따라 적었으나 주당 뿌리수, 뿌리길이 및 무게는 50ppmrn가 가장 많았다.

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단근, 줄기 절단과 식재 밀도에 따른 음나무(Kalopanax septemlobus) 묘목의 활착 및 생장 특성 (Effects of Root Pruning, Stem Cutting and Planting Density on Survival and Growth Characteristics in Kalopanax septemlobus Seedlings)

  • 강호상
    • 한국환경복원기술학회지
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    • 제16권3호
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    • pp.97-105
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    • 2013
  • Kalopanax septemlobus (Thunb. ex Murray) Koidz. is natively distributed in Korea. The importance of this species has been increased not only for high quality timber but for medicinal and edible uses. However, increasing market demand of K. septemlobus with illegal cutting and overexploitation has resulted in its rapid depletion and destruction of natural habitat. This study was conducted to understand the survival rate and growth characteristics of planted K. septemlobus seedlings with treatment of root pruning, stem cutting and planting density. The survival rate and growth of height and root-collar diameter for one- and two-year old seedlings with different planting densities were investigated in the clear-cut area of a Pinus densiflora stand for five years. One-year-old seedlings were treated with or without root pruning and planted with three density levels (5,000 trees $ha^{-1}$, 10,000 trees $ha^{-1}$, and 40,000 trees $ha^{-1}$). Two-year-old seedlings were treated with and without stem cutting and planted with the density of 5,000 trees $ha^{-1}$. The survival rate of one-year-old seedlings with root pruning treatment in the density of 10,000 trees $ha^{-1}$ was 92%, while that without root pruning in the density of 40,000 trees $ha^{-1}$ was 67% after five years. The height of one-year-old seedlings has been significantly affected only by planting density in the $5^{th}$ year. The survival rate of the two-year-old seedlings with stem cutting was 75.5% and greater than control (67.3%) in the $5^{th}$ year but no difference in height was shown between the two treatments from three years after plantation.

용토와 생장조절제 처리가 노빌계 덴드로비움의 삽목번식에 미치는 영향 (Effect of Cutting Media and Growth Regulators on the Cutting of Dendrobium nobile)

  • 김한균;남유경;이종석
    • 화훼연구
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    • 제18권1호
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    • pp.23-28
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    • 2010
  • 본 실험은 Dendrobium nobile계 신품종인 'Candy'와 'Fizz', 'Princess'를 대상으로 줄기 삽목번식법을 확립하고자 수행하였다. 매질실험에서 삽목 60일 후 측아발생률은 'Fizz'가 perlite+vermiculite 혼용구에서 83.3%로 가장 높았고, 발근률은 'Candy'와 'Fizz'에서는 발근이 되지 않았으나 'Prince'의 경우 삽목 60일 후 perlite+vermiculite 혼용구에서 10%의 발근률을 나타냈다. 오옥신 종류 및 농도별 실험에서 측아발생률은 'Candy'를 제외하고는 삽목 60일 이후부터 높은 증가율을 나타내었으나 'Fizz'는 IBA 200ppm 처리의 86.7%를 제외하고는 대조구와 처리간에 차이가 없었다. 착엽수는 대조구에 비해 'Candy'와 'Fizz'의 경우 IBA 200ppm에서 높은 발생률을 나타냈다. 발근률은 'Prince'에서는 IBA 200과 NAA 50ppm에서 대조구보다 2배의 높은 발근률을 나타냈다. BA와 kinetin의 농도별 실험에서 'Candy'는 삽목 60일 후 BA 50ppm에서 20%의 측아발생률을 나타냈다. 'Fizz' 품종은 전체적으로 측아발생률이 30일 이후부터 증가하여 60일 이후에는 대조구의 77%에 비해 BA 200ppm에서 100%이었다. 그러나 kinetin의 경우 농도에 관계없이 대조구에 비해 낮게 나타났다. 착엽수도 Fizz와 Prince에서 측아발생률과 유사한 경향으로서 BA 200ppm에서 효과가 뚜렷하였으나 모든 품종에서 발근에는 영향을 미치지 못했다.

Empirical Study on Digital Core-Banking System

  • Kang, Hee Yong;Weon, Dal Soo
    • International Journal of Internet, Broadcasting and Communication
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    • 제9권2호
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    • pp.48-57
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    • 2017
  • In the last few years, banks have experienced more challenging market than any other times. They need to find new ways to reconnect with their customers and rebuild their trust. But in the race to the future some banks are taking clear lead. Research works show that while high perform leading banks are different, they also share some common characteristics and principles that have allowed them to move ahead to profitable growth. Cost cutting is no longer enough to succeed in tomorrow's world. Instead, the IT function needs to work shoulder-to-shoulder with the business to support the growth agenda. Therefore "C" level's attention is moving from cost reduction towards customer experience, speeding to market for new offerings, analytics and distribution channel enhancements, taking advantage of several levers that will shape the technology agenda for the high performing organization. Next generation of digital core-banking solutions will improve pre-existing capabilities, introduce new innovations and drive qualities such as flexibility and scalability to support time to market.

평판익 후연의 형상에 따른 후류 특성 (Charateristics of Wake Flow in a Flat Plate Blade Having TS and TP Cutting)

  • 장춘만;;김광용
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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    • pp.452-455
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    • 2004
  • The influence of wake flow on a flat-plate blade having different shapes near the hailing edge has been investigated in this paper. Two different shapes near the trailing edge namely the pressure surface cutting (TP) and the suction surface cutting (TS) have been used. The calculation has been performed for two different angles of attack (a =10 and 15 degree) in both the cases. RANS equations have been solved using SST-model as a turbulence closure. Cp and CL values obtained for TS are higher compared to those obtained for TP. Also, the vorticity distribution obtained in case of TS is stronger as compared to that obtained in the case of TP The Karmann Vortex is observed in both the cases but it is more clear in TS case. It is found that in the case of TS, flow separation does not occur upto the trailing edge on both the suction and the pressure sides of the blade while in the case of TP, the flow separateson the pressure surface near the trailing edge of the flat-plate blade.

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강원도 남부지역에서 소나무림 벌채 후 초기 종조성 변화 (Early Successional Change of Vegetation Composition After Clear Cutting in Pinus densiflora Stands in Southern Gangwon Province)

  • 조용찬;김준수;이창석;조현제;이호영;배관호
    • 한국산림과학회지
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    • 제100권2호
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    • pp.240-245
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    • 2011
  • 강원도 남부 지역의 발달단계가 다른 소나무림 벌채지에서 16년 동안의 식생 변화를 연구하였다. 교란 후, 천이 궤적 및 환경 변화를 온도, 상대습도, 서열분석(Detrended Correspondence Analysis, DCA), Multiple Responses Permutation Procedure(MRPP) 및 지표종 분석(Indicator Species Analysis, ISPAN) 등을 통하여 분석하였다. 벌채 직후, 수관열림도는 대조구와 비교하여 세 배(1yr 68.3% 및 R1 23.0%)로 급격히 증가한 후 감소하였으나, 상대습도는 비교적 작은 변화(약 6% 감소)를 나타내었다. DCA 결과, 벌채 후 초기에는 종조성이 이질적으로 변화하였으나, 점차 벌채 이전(대조구)의 것과 유사하게 발달하였다. MRPP 결과, 각 발달 단계(1yr, 3yr, 10yr 및 16yr)의 종 조성은 대조구(R1, R3, R10 및 R16)의 것과 유의한 차이를 보였다. 1yr 및 3yr에서는 목본성 종이, 10yr 및 16yr에서는 초본 종들이 주요 종으로 분석되어, 교란 직후에는 목본성 종들이 활발한 재생을 나타내며, 이후 초본 식생이 발달하는 것을 보였다. 연구 대상지역의 천이는 초기 식물상 조성 모델로 설명할 수 있을 것으로 판단된다.

Yield and Chemical Composition of Cassava Foliage and Tuber Yield as Influenced by Harvesting Height and Cutting Interval

  • Khang, Duong Nguyen;Wiktorsson, Hans;Preston, Thomas R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권7호
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    • pp.1029-1035
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    • 2005
  • A 3${\times}$4 factorial field experiment with a complete randomised split-plot design with four replicates was conducted from June 2002 to March 2003 at the experimental farm of the Nong Lam University, Ho Chi Minh City, Vietnam, to determine effects of different harvesting heights (10, 30 and 50 cm above the ground) and cutting intervals (45, 60, 90 and 285 days) on yield of foliage and tubers, and chemical composition of the foliage. Cassava of the variety KM 94 grown in plots of 5 m${\times}$10 m at a planting distance of 30 cm${\times}$50 cm was hand-harvested according to respective treatments, starting 105 days after planting. Foliage from the control treatment (285 days) and all tubers were only harvested at the final harvest 285 days after planting. Dry matter and crude protein foliage yields increased in all treatments compared to the control. Mean foliage dry matter (DM) and crude protein (CP) yields were 4.57, 3.53, 2.49, and 0.64 tonnes DM $ha^{-1}$ and 939, 684, 495 and 123 kg CP $ha^{-1}$ with 45, 60, 90 and 285 day cutting intervals, respectively. At harvesting heights of 10, 30 and 50 cm the DM yields were 4.27, 3.67 and 2.65 tonnes $ha^{-1}$ and the CP yields were 810, 745 and 564 kg $ha^{-1}$, respectively. The leaf DM proportion was high, ranging from 47 to 65%. The proportion of leaf and petiole increased and the stem decreased with increasing harvesting heights and decreasing cutting intervals. Crude protein content in cassava foliage ranged from 17.7 to 22.6% and was affected by harvesting height and cutting interval. The ADF and NDF contents of foliage varied between 22.6 and 30.2%, and 34.2 and 41.2% of DM, respectively. The fresh tuber yield in the control treatment was 34.5 tonnes $ha^{-1}$. Cutting interval and harvesting height had significant negative effects on tuber yield. The most extreme effect was for the frequent foliage harvesting at 10 cm harvesting height, which reduced the tuber yield by 72%, while the 90 day cutting intervals and 50 cm harvesting height only reduced the yield by 7%. The mean fresh tuber yield decreased by 56, 45 and 27% in total when the foliage was harvested at 45, 60 and 90 day cutting intervals, respectively. It is concluded that the clear effects on quantity and quality of foliage and the effect on tuber yield allow alternative foliage harvesting principles depending on the need of fodder for animals, value of tubers and harvesting cost. An initial foliage harvest 105 days after planting and later harvests with 90 days intervals at 50 cm harvesting height increased the foliage DM and CP yield threefold, but showed only marginal negative effect on tuber yield.

Seasonal Phosphorus Dynamics in a Forest Stream Water Following Different Harvests

  • Park, Byung Bae
    • 한국산림과학회지
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    • 제97권2호
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    • pp.181-186
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    • 2008
  • Even small changes in phosphorus concentrations in stream water could cause eutrophication because of very low level of phosphorus concentrations in natural waters. I investigated the impact of strip cut and clear cut on phosphorus concentrations in stream water at the Hubbard Brook Experimental Forest and investigated stream water phosphorus concentrations as a function of flow rate and season (as well as cutting history). Mean phosphate concentrations in the control (undisturbed forest) increased $1.9{\mu}g\;L^{-1}\;to\;2.6{\mu}g\;L^{-1}$, while strip cut treatment increased phosphate concentrations in stream water $2.2{\mu}g\;L^{-1}\;to\;3.7{\mu}g\;L^{-1}$ during the same period. There was no significant effect of clear cut treatment on phosphate concentrations in stream water. No relationships were found between discharge rate and phosphate concentrations, but the magnitude of fluctuation were increased during two decades in undisturbed forest: $1-5{\mu}g\;L^{-1}$ from 1963 to 1975 and $1-12{\mu}g\;L^{-1}$ from 1983 to 1995. Based on this study, forest harvests with buffer zone will not make a problem by imported phosphate to cause eutrophication in natural water.