• Title/Summary/Keyword: Greenwood

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Effect of Cutting Dates and Rooting Promoters on Rooting of Rhododendron mucronulatum Turcz. (삽목시기(揷木時期) 및 발근촉진제(發根促進劑) 처리가 진달래(Rhododendron mucronulatum Turcz.)의 발근(發根)에 미치는 영향(影響))

  • Hwang, Seong Kon;Hwang, Hwan Joo;Kim, Ki Sun
    • Horticultural Science & Technology
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    • v.16 no.1
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    • pp.33-36
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    • 1998
  • This study was carried out to examine the effects of cutting dates and rooting promoters on rooting of the Rhododendron mucronulatum Turcz. The rooting percentage in greenwood cutting was high in June and decreased after July 3, when reproductive growth began. The best rooting percentage(92.5%) occurred when cutting was completed on June 12. There was no difference in rooting potentials between the greenwood straight cutting and the greenwood heel cutting. Cuttings of R. mucronulatum for. albiflora showed high rooting percentage(85%) similar to the cuttings of R. mucronulatum. Dipping cuttings in NAA $2,000mg{\cdot}L^{-1}$ solution for 15 sec increased the rooting percentage up to 97.5%, and also promoted root growth.

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Cutting Propagation of Dendropanax morbifera $L_{EV}$. (황칠나무 삽목번식에 관한 연구)

  • Choi, Seong-Kyu
    • Korean Journal of Medicinal Crop Science
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    • v.6 no.4
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    • pp.251-257
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    • 1998
  • This experiment was carried out to establish cutting propagation method of dendropanax morbifera $L_{EV}\$. at Wando in Chonnam, native area. The hardwood cutting and the greenwood cutting were able to be used as propagation method, but callus formation and rooting ratio in the greenwood cutting were higher than in hardwood cutting. The optimum cutting time was February to middle of March in hardwood cutting and July to August in greenwood cutting. The earthen-ball cutting method was better than normal cutting method in callus formation and rooting ratio. The rooting in different bed soils was the best at sand-loam soil. The application of IBA 100ppm promoted rooting.

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Cuttings for Mass Propagation Affecting the Impact of Increasing Reproductive Efficiency of Schisandra chinensis (오미자 대량증식을 위한 삽목번식 효율증대에 영향을 미치는 요인)

  • Kim, Jong Yeob;Kim, Chang Su;You, Dong Hyun;Kim, Dong Won;Choi, Dong Chil;Kim, Jeong Man;Oh, Nam Ki;Park, Chun Geun;Ahn, Young Sup;Lee, Kang Soo
    • Korean Journal of Medicinal Crop Science
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    • v.22 no.3
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    • pp.231-236
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    • 2014
  • This experiment was carried out to establish the optimum cutting time, plant growth regulator, and bed-soil for rooting by greenwood cutting of Schisandra chinensis. Approximately 7 cm long-shoots of greenwood cuttings were transplanted by various cutting times, plant growth regulators, and bed-soils in the plastic-film house. The rooting rate of greenwood cutting was 12.5% in the April 5th, 73.5% in the May 8th, and 75.5% in the August 5th. The number and length of primary root in greenwood cutting were more in the early May than those in the early August. For mass propagation of Schisandra chinensis. using greenwood cutting, shoots were treated with plant growth regulators on May to increase rooting rate. Rooting rate was 100% with IAA $50mg/{\ell}$, 92.9% with NAA $100mg/{\ell}$, and NAA $1,000mg/{\ell}$, for 60 min. To select effective media for rooting, various medias for bed-soil were treated by single and mixture form for 100 days after cutting. Rooting rate was 91.8% in the single treatment of peat moss or decomposition of granite soil, and this result was better than those in other treatment. The treatment by 1 : 1 mixture of peat moss and horticulture bed soil was rooting with 94.0% best rooting rate.

Numerical Calculation of Transformation Plasticity Using a FE Analysis Coupled with n Phase Field Model (상장모델과 유한요소법의 연계해석을 통한 변태소성 전산모사)

  • Cho, Y.G.;Kim, J.Y.;Cha, P.R.;Lee, J.K.;Han, H.N.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.318-321
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    • 2009
  • Transformation plasticity is that when a phase transformation of ferrous or non-ferrous alloys progresses even under an extremely small applied stress compared with a yield stress of the material, a permanent deformation occurs. One of widely accepted description for the transformation was proposed by Greenwood and Johnson [1]. Their description is based on an assumption that a weaker phase of an ideal plastic material could deform plastically to accommodate the externally applied stress and the internal stress caused by the volumetric change accompanying the phase transformation. In this study, an implicit finite element model was developed to simulate the deformation behavior of a low carbon steel during phase transformation. The finite element model was coupled with a phase field model, which could simulate the kinetics for ferrite to austenite transformation of the steel. The thermo-elasto-plastic constitutive equation for each phase was adopted to confirm the weaker phase yielding, which was proposed by Greenwood and Johnson [1]. From the simulation, the origin of the transformation plasticity was quantitatively discussed comparing with the other descriptions of it.

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Impact of Strain Effects on Hole Mobility and Effective Mass in the p-Channel Nanowire Cross-Section

  • Jang, Geon-Tae
    • Proceeding of EDISON Challenge
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    • 2017.03a
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    • pp.424-427
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    • 2017
  • This study investigated the effect of strain on hole mobility and hole effective mass in a p-channel rectangular nanowire with two-dimensional confinement. We obtained the valence energy band structure using the six-band k.p method and calculated the mobility and effective mass of the hole in the [100] direction taking the strain effect into account in the inversion region. The hole mobility of strained silicon was calculated using Kubo-Greenwood formalism. As a result, it showed good performance compared to relaxed silicon, but its magnitude was insignificant.

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Study on the Propagation of Vitex rotundifolia for Establishment of Natural Aromatic Resources (향료자원 조성을 위한 순비기나무의 증식에 관한 연구)

  • 김계환;박종민
    • Journal of Korea Foresty Energy
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    • v.23 no.1
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    • pp.26-37
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    • 2004
  • This study was to investigate the rational propagation of the Vitex rotundifolia, which is distributed as a community naturally at coastal area in Korea. The germination rate of ordinary temperature stored fruits was the highest with 67%. In the matter of the number of seedlings per fruit, 1 seed germinated fruit was the most with 40.3 % and the mean was 1.4 seedlings per fruit. The best rooting rate of both greenwood and hardwood cutting was 96.7% in the case of cuttings soaked in IBA 2500ppm for 1 minute on the Compost+Sand bed-soils. Generally the root development of cuttings was higher in the high IBA concentration with soaking in a moment than in the low IBA concentration with soaking in long time, and bed-soils mixed with sands and composts. And in the rooting rate, greenwood cutting was better about 10% than hardwood cutting of Vitex rotundifolia.

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Evaluation of the Resistance Bias Factors to Develop LRFD for Gravel Compaction Piles (LRFD 설계를 위한 쇄석다짐말뚝공법의 저항편향계수 산정)

  • Han, Yong-Bae;Park, Joon-Mo;Jang, Yeon-Soo
    • Journal of the Korean Geotechnical Society
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    • v.28 no.2
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    • pp.43-55
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    • 2012
  • In this study, the resistance bias factors are calculated to determine the resistance factor of Gravel Compaction Piles which is one of the soft ground improvement methods. In order to calculate resistance bias factors for gravel compaction piles, two ultimate bearing capacities were analyzed. One is the ultimate bearing capacity in 2.54 cm settlement measured using data of the field loading test on 41 piles and the other is the ultimate bearing capacity calculated using the seven equations concerning bulging failure. The results of analysis show that the probability density function of the calculated ultimate bearing capacities has a lognormal distribution. Resistance bias factor and the coefficient of variation for Greenwood equation are 0.91 and 0.38, respectively, and for those of Hughes & Withers are 1.19 and 0.39. The two equations are suitable for calculating resistance factors for LRFD of soil improvement using gravel compaction piles.

A Study on the Policy of Improving Archival Professionals' Education System: Focusing on the Accreditation System (기록전문직 교육제도 개선 방안 연구: 인증제도를 중심으로)

  • Kim, Youseung
    • Journal of Korean Society of Archives and Records Management
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    • v.20 no.1
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    • pp.159-175
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    • 2020
  • This study aims to discuss policy alternatives for improving the curriculum of archival studies. As a theoretical study, it organized classical professional theories such as Greenwood and Good and confirmed that the archival professionals met all six criteria for professional occupations claimed by Perk. However, from the perspective that professionalism is not completed at any point in time, but is a constant pursuit, education and training of archival professionals, and the legal system that supports it, were analyzed. In addition, the case of the British ARA and the US ACA, which are implementing a professional certification system, was analyzed in the context that professionals should set their own standards for education and training to protect their authority and have norms for professional communities. In conclusion, policy alternatives centered on the academic training guidelines and the certification system were presented.

Sliding Friction of Elastomer Composites in Contact with Rough Self-affine Surfaces: Theory and Application (자기-아핀 표면 특성을 고려한 유기탄성체 복합재료 마찰 이론 및 타이어 트레드/노면 마찰 응용)

  • Bumyong Yoon;Yoon Jin Chang;Baekhwan Kim;Jonghwan Suhr
    • Composites Research
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    • v.36 no.3
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    • pp.141-153
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    • 2023
  • This review paper presents an introduction of contact mechanics and rubber friction theory for sliding friction of elastomer composites in contact with rough surfaces. Particularly, Klüppel & Heinrich theory considers the self-affine (or fractal) characteristic for rough surfaces to predict adhesion and hysteresis frictions of elastomers based on the contact mechanics of Greenwood & Williamson. Due to dynamic excitation process of elastomer composites while sliding in contact with multiscale surface roughness (or asperity), viscoelastic properties in a wide frequency range becomes major contributor to friction behaviors. A brief description and examples are provided to construct a viscoelastic master curve considering nonlinear viscoelasticity of elastomer composites. Finally, application of rubber friction theory to tire tread compounds in traction with road surfaces is discussed with several experimental and theoretical results.

The High temperature stability limit of talc, $Mg_3Si_4O_{10}(OH)_2$ (활석 $Mg_3Si_4O_{10}(OH)_2$의 고온 안정영역에 관한 실험적 연구)

  • 조동수;김형식
    • The Journal of the Petrological Society of Korea
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    • v.6 no.2
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    • pp.123-132
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    • 1997
  • In the system $MgO-SiO_2-H_2O$, Talc[$Mg_3Si_4O_{10}(OH)_2$] has been synthesized hydrothermally at 200 MPa, $600^{\circ}C$ from the oxide mixture of the bulk composition of talc. The oxide mixture of the bulk composition of anthophyllite$[Mg_7Si_8O_{22}(OH)2]$ converted to talc, enstatite $(MgSiO_3)$, quartz at 200 MPa, $750^{\circ}C$ with excess of $H_2O$. In low to medium pressure metramorphism, enstatite-talc assemblage is metastable relative to anthophyllite with the reaction talc + 4 enstatite=anthophyllite (Greenwood, 1963). The high temperature stability of talc is bounded with the dehydration reaction to anthophyllite rather than that to enstatite(Greenwood, 1963; Chernosky et al., 1985). Therefore our experiment result assemblage, enstatite-talc-quatz at 200 MPa, $750^{\circ}C$ from oxide mixture of bulk compostion of anthophyllite is metastable assemblage. The hydrothermal experiment performed at 41 to 243 MPa, 680 to $760^{\circ}C$ with the starting material composed of synthetic talc, enstatite and quartz. Talc or enstatite grows during the runs and no extra phases including anthophyllite nucleated. Based on the increase or decrease of the each phase from run products, one of the possible reactions is talc=3 enstatite+quartz+H_2O$. The reversal bracket of the reaction is 699 to $700^{\circ}C$ at 100 MPa. Talc is stable up to $740^{\circ}C$ at 200 MPa and enstatite grow at $680^{\circ}C$, 40 MPa and at $760^{\circ}C$, 250 MPa. Though the high temperature limit of talc around 200 MPa is bounded thermodynamically by the reaction, 7 talc=3 anthophyllite+4 quartz+4 H_2O$, talc persisted throughout the previous reaction up to the reaction, talc=3 enstatite+quartz+$H_2O$.

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