• Title/Summary/Keyword: F.D.M.

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An Establishment of the Forecasting System for General Index using Fuzzy Delphi Method (Fuzzy Delpi 법(法)을 이용한 일반 지수 예측 시스템 구축)

  • Kim, Chang-Eun;Choi, Hwan-Seok
    • IE interfaces
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    • v.9 no.1
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    • pp.53-62
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    • 1996
  • The Delphi method is widely used for long and middle range forecasting in management science. It is a method by which the subjective data of experts are made to converge using statistical analysis. The Fuzzy Delphi Method(F.D.M.), anew application of the Delphi method using Triangular Fuzzy Numbers(T.F.N.), can help to predict the uncertainty, synthesize the opinion and calculation of those assumed dissemblance index and fuzzy distance. Furthermore, the programming of the F.D.M. process to feed paper and data back to experts can make them more accurately predict the various information.

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Acclimation of maximum quantum yield of PSII and photosynthetic pigments of Panax quinquefolius L. to understory light

  • Fournier, Anick R.;T.A., John;Khanizadeh, Shahrokh;Gosselin, Andre;Dorais, Martine
    • Journal of Ginseng Research
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    • v.32 no.4
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    • pp.347-356
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    • 2008
  • Forest-grown American ginseng (Panax quinquefolius L.) is exposed to daily and seasonal light variations. Our goal was to determine the effect of understory light changes on the maximum quantum yield of photosystem II, expressed as $F_v/F_m$, and photosynthetic pigment composition of two-year-old plants. Understory light photon flux density and sunfleck durations were characterized using hemispherical canopy photography. Our results showed that understory light significantly affected the $F_v/F_m$ of American ginseng, especially during the initial development of the plants when light levels were the highest, averaging 28 mol $m^{-2}d^{-1}$. Associated with low $F_v/F_m$ during its initial development, American ginseng had the lowest levels of epoxidation state of the xanthophyll cycle of the season, suggesting an active dissipation of excess light energy absorbed by the chlorophyll pigments. As photon flux density decreased after the deployment of the forest canopy to less than 10 mol $m^{-2}d^{-1}$, chlorophyll a/b decreased suggesting a greater investment in light harvesting pigments to reaction centers in order to absorb the fleeting light energy.

Rare-Earth Metal Complex-Functionalized Mesoporous Silica for a Potential UV Sensor (잠재적인 UV 센서를 위한 희토류 금속착물이 기능화된 메조다공성 실리카)

  • Sung Soo Park;Mi-Ra Kim;Weontae Oh;Yedam Kim;Yeeun Lee;Youngeon Lee;Kangbeom Ha;Dojun Jung
    • Journal of Adhesion and Interface
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    • v.24 no.4
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    • pp.136-142
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    • 2023
  • In this study, TEOS was used as a silica source, and a triblock copolymer (P123) was used as a template to produce mesoporous silica with a well-ordered hexagonal mesopore array through a self-assembly method and hydrothermal process under acidic condition. (Surfactant-extracted SBA-15). Surfactant-extracted SBA-15 showed the particle shape of a short rod with a size of approximately 980 nm. The surface area and pore diameter were 730 m2g-1 and 70.8 Å, respectively. Meanwhile, aminosilane (3-aminopropyltriethoxysilane, APTES) was grafted into the mesopores using a post-synthesis method. Mesoporous silica (APTES-SBA-15) modified with aminosilane had a well-ordered pore structure (p6mm) and well-maintained the particle shape of short rods. The surface area and pore diameter of APTES-SBA-15 decreased to 350 m2g-1 and 60.7 Å, respectively. APTES-modified mesoporous silica was treated with a solution of rare earth metal ions (Eu3+, Tb3+) to synthesize a mesoporous silica material in which rare earth metal complexes were introduced into the mesopores. (Eu/APTES-SBA-15, Tb/APTES-SBA-15) These materials exhibited characteristic photoluminescence spectra by λex=250 nm. (5D47F5 (543.5 nm), 5D47F4 (583.5 nm), 5D47F3 (620.2 nm) transitions for Tb/APTES-SBA-15; 5D07F0 (577.7 nm), 5D07F1 (592.0 nm), 5D07F2 (614.9 nm), 5D07F3 (650.3 nm) and 5D07F4 (698.5 nm) transitions for Eu/APTES-SBA-15)

Flexible 3D ZnO/Polymer Composite by Simple-Step Growth Processing for Highly Photocatalytic Performance

  • Lee, Hyun Uk;Park, So Young;Seo, Jung Hye;Son, Byoungchul;Lee, Jouhahn
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.412-412
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    • 2014
  • Zinc oxide (ZnO) is one of the most powerful materials for purifying organic pollutants using photocatalytic activity. In this study, we have introduced a novel method to design highly photoreactive flexible 3 dimensional (3D) ZnO nanocomposite [F-ZnO-m (m: reaction time, min)] by electrospinning and simple-step ZnO growth processing (one-step ZnO seed coating/growth processing). Significantly, the F-ZnO-m could be a new platform (or candidate) as a photocatalytic technology for both morphology control and large-area production. The highest photocatalytic degradation rate ([k]) was observed for F-ZnO-m at 2.552 h-1, which was 8.1 times higher than that of ZnO nanoparticles (NPs; [k] = 0.316 h-1). The enhanced photocatalytic activity of F-ZnO-m may be attributed to factors such as large surface area. The F-ZnO-m is highly recyclable and retained 98.6% of the initial decolorization rate after fifteen cycles. Interestingly, the F-ZnO-m samples show very strong antibacterial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) after exposure to UV-light for 30 min. The antibacterial properties of F-ZnO-m samples are more effective than those of ZnO NPs. More than 96.6% of the E. coli is sterilized after ten cycles. These results indicate that F-ZnO-m samples might have utility in several promising applications such as highly efficient water/air treatment and inactivation of pathogenic microorganisms.

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Highly Photocatalytic Performance of flexible 3 Dimensional (3D) ZnO nanocomposite

  • Lee, Hyun Uk;Seo, Jung Hye;Son, Byoungchul;Kim, Hyeran;Yun, Hyung Joong;Jeon, Cheolho;Lee, Jouhahn
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.270.1-270.1
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    • 2013
  • Zinc oxide (ZnO) is one of the most powerful materials for purifying organic pollutants using photocatalytic activity. In this study, we have introduced a novel method to design highly photoreactive flexible 3 dimensional (3D) ZnO nanocomposite [F-ZnO-m (m: reaction time, min)] by electrospinning and simple-step ZnO growth processing (one-step ZnO seed coating/growth processing). Significantly, the F-ZnO-m could be a new platform (or candidate) as a photocatalytic technology for both morphology control and largearea production. The highest photocatalytic degradation rate ([k]) was observed for F-ZnO-m at 2.552 h-1, which was 8.1 times higher than that of ZnO nanoparticles (NPs; [k] = 0.316 h-1). The enhanced photocatalytic activity of F-ZnO-m may be attributed to factors such as large surface area. The F-ZnO-m is highly recyclable and retained 98.6% of the initial decolorization rate after fifteen cycles. Interestingly, the F-ZnO-m samples show very strong antibacterial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) after exposure to UV-light for 30 min. The antibacterial properties of F-ZnO-m samples are more effective than those of ZnO NPs. More than 96.6% of the E. coli is sterilized after ten cycles. These results indicate that F-ZnO-m samples might have utility in several promising applications such as highly efficient water/air treatment and inactivation of pathogenic microorganisms.

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A CHARACTERIZATION OF M-HARMONICITY

  • Lee, Jae-Sung
    • Bulletin of the Korean Mathematical Society
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    • v.47 no.1
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    • pp.113-119
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    • 2010
  • If f is M-harmonic and integrable with respect to a weighted radial measure $\upsilon_{\alpha}$ over the unit ball $B_n$ of $\mathbb{C}^n$, then $\int_{B_n}(f\circ\psi)d\upsilon_{\alpha}=f(\psi(0))$ for every $\psi{\in}Aut(B_n)$. Equivalently f is fixed by the weighted Berezin transform; $T_{\alpha}f = f$. In this paper, we show that if a function f defined on $B_n$ satisfies $R(f\circ\phi){\in}L^{\infty}(B_n)$ for every $\phi{\in}Aut(B_n)$ and Sf = rf for some |r|=1, where S is any convex combination of the iterations of $T_{\alpha}$'s, then f is M-harmonic.

SUBREGULAR POINTS FOR SOME CASES OF LIE ALGEBRAS

  • KIM, Y.K.;SO, K.H.;JEONG, J.W.;PARK, D.Y.;CHOI, S.H.
    • Honam Mathematical Journal
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    • v.21 no.1
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    • pp.75-95
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    • 1999
  • Dimensions of irreducible $so_5(F)$-modules over an algebraically closed field F of characteristics p > 2 shall be obtained. It turns out that they should be coincident with $p^{m}$, where 2m is the dimension of coadjoint orbits of ${\chi}{\in}so_5(F)^*{\backslash}0$ as Premet asserted. But there is no subregular point for $g=sp_4(F)=so_5(F)$ over F.

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Exchange Decoupling Of $Fe_3$Fe_3B+Nd_2Fe_{14}B Spring Magnet Powder Compact (Fe_3B+Nd_2Fe_{14}B Spring magnet분말 압분체의 Exchange Decoupling)

  • 한종수;양충진;박언병
    • Journal of the Korean Magnetics Society
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    • v.11 no.5
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    • pp.232-238
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    • 2001
  • Experimentally it is well known that the magnetic properties significantly deteriorate when nanocomposite bonded magnet are made from nanocomposite ribbon. A decrease in maximum energy product of F $e_3$B+N $d_2$F $e_{14}$B nanocomposite from 14 MGOe in nanocomposite ribbon to 6.5 MGOe in powder compact was fecund to be general. Thus, the present study is focused on finding out the root of exchange decoupling of N $d_4$F $e_{73.5}$ $Co_3$H $f_{0.5}$G $a_{0.5}$ $B_{18.5}$ nanocomposite powder compacts. The exchange decoupling behavior of the powder compact of F $e_3$B+N $d_2$F $e_{14}$B composition was studied by measuring DC demagnetization and isothermal remanent demagnetization curves, which are essential for plotting produced $\delta$M curve. From the $\delta$M plot the deterioration in the magnetic properties resulted from the fact that the magnetostatic interaction became dominant rather thanthe exchange interaction in powder compact. It is concluded that the demagnetization behavior governed by the dominant magnetostatic interaction reduced the remanence magnetization, which caused the reduction of maximum energy Product of the powder compact. We also found that the elimination of residual stress which is unavoidably accumulated during grinding process enhanced the magnetic properties considerably.bly.bly.

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