• Title/Summary/Keyword: D.A.R.F

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Solution-State Structure of Native Coenzyme F430 by NMR Methods

  • 원호식;Karl D. Olson;박지석;Ralph S. Wolfe;Dennis R. Hare;Michael F. Summers
    • Bulletin of the Korean Chemical Society
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    • v.16 no.7
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    • pp.649-653
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    • 1995
  • Solution-state structure of native F430 was determined by using NMR methods and NMR-based distance geometry (DG) computations. Structures were generated with loose NOE-derived interproton distance restraints (2.0-2.5 Å, 2.0-3.5 Å and 2.0-4.5 Å for strong, medium, and weak NOE cross-peak intensities, respectively). 2D NOESY back-calculations of structures were subsequently carried out for establishing the consistence between experimental data and DG-model structures. The back-calculated 2D NOESY spectra of resulting DG structures were well consistent with experimental 2D NOESY spectra. Superposition of 20 independent structures with macrocyclic ring atoms and all atoms of F430 afforded pairwise root mean square deviations (RMSD) of 0.025-0.125 Å and 0.64-1.3 Å, respectively. The macrocyclic rings of structures are well converged to a unique conformation with saddle-shaped deformation whereas most of side chains are not converged. The average dihedral angle (N1-N2-N3-N4, 27.78±1.50°) of 20 DG-structures exhibits that the macrocyclic ring conformation is puckered as much as 12,13-diepimeric F430 (28.75±4.07°).

A Study on the Input Power Factor Correction & THD Reduction of Inverter Airconditioner (인버터 에어컨의 입력 역률 개선 및 하모닉 저감에 관한 연구)

  • Kim, Seong-Hwan;Lee, In-Ho;Yoo, Ji-Yoon;Kim, Tae-Duk;Rae, Young-Dawn;Park, Yoon-Ser
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.235-237
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    • 1995
  • The demands of minimizing the reactive power and reducing. the current harmonics are increasing nowadays. The inverter airconditioner needs high power and it operates with wide load range. Conventionally, ah huge LC passive filter is used in airconditioner to improve the P.F and to reduce current harmonics which doesn't gives good results. In this paper, a design of active power factor correction(PFC) circuit for inverter air conditioner is described. To improve the P.F and to reduce the THD, an average current controlled active PFC is designed and tested. Experimental results show that the developed system achieves almost unity P.F and low THD for all load range.

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Experimental Study on the Characteristics of Rapid Chilled Converter Slag by Watering

  • Lee, Keun-Jae;Yoo, Seung-Yeup;Koo, Ja-Sul;Cho, Bong-Suk;Lee, Hoon-Ha
    • International Journal of Concrete Structures and Materials
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    • v.5 no.2
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    • pp.133-137
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    • 2011
  • In this study, a physical and chemical properties analysis was conducted for PCSP to evaluate properties of its materials and, for comparison purpose, was also conducted for CSP. The result of experiment confirmed improvement of iron recovery rate due to introduction of rapid water-cooling equipment and greater density of exterior and interior structure through SEM observation and porosity measurement. Also, SEM, XRD and DSC-TGA analysis showed that content of f-CaO in PCSP was minuscule so it was decided that problems of material stability including f-CaO-caused bulging failure, which has been problematic, can be solved.

Singular Representation and Finite Element Methods

  • 김석찬
    • Proceedings of the Korean Society of Computational and Applied Mathematics Conference
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    • 2003.09a
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    • pp.9-9
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    • 2003
  • Let $\Omega$ be a bounded, open, and polygonal domain in $R^2$ with re-entrant corners. We consider the following Partial Differential Equations: $$(I-\nabla\nabla\cdot+\nabla^{\bot}\nabla\times)u\;=\;f\;in\;\Omega$$, $$n\cdotu\;0\;0\;on\;{\Gamma}_{N}$$, $${\nabla}{\times}u\;=\;0\;on\;{\Gamma}_{N}$$, $$\tau{\cdot}u\;=\;0\;on\;{\Gamma}_{D}$$, $$\nabla{\cdot}u\;=\;0\;on\;{\Gamma}_{D}$$ where the symbol $\nabla\cdot$ and $\nabla$ stand for the divergence and gradient operators, respectively; $f{\in}L^2(\Omega)^2$ is a given vector function, $\partial\Omega=\Gamma_{D}\cup\Gamma_{N}$ is the partition of the boundary of $\Omega$; nis the outward unit vector normal to the boundary and $\tau$represents the unit vector tangent to the boundary oriented counterclockwise. For simplicity, assume that both $\Gamma_{D}$ and $\Gamma_{N}$ are nonempty. Denote the curl operator in $R^2$ by $$\nabla\times\;=\;(-{\partial}_2,{\partial}_1$$ and its formal adjoint by $${\nabla}^{\bot}\;=\;({-{\partial}_1}^{{\partial}_2}$$ Consider a weak formulation(WF): Find $u\;\in\;V$ such that $$a(u,v):=(u,v)+(\nabla{\cdot}u,\nabla{\cdot}v)+(\nabla{\times}u,\nabla{\times}V)=(f,v),\;A\;v{\in}V$$. (2) We assume there is only one singular corner. There are many methods to deal with the domain singularities. We introduce them shortly and we suggest a new Finite Element Methods by using Singular representation for the solution.

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On the Strong Law of Large Numbers for Convex Tight Fuzzy Random Variables

  • Joo Sang Yeol;Lee Seung Soo
    • Proceedings of the Korean Statistical Society Conference
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    • 2001.11a
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    • pp.137-141
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    • 2001
  • We can obtain SLLN's for fuzzy random variables with respect to the new metric $d_s$ on the space F(R) of fuzzy numbers in R. In this paper, we obtain a SLLN for convex tight random elements taking values in F(R).

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Isolation and identification of Aureobasidium spp. from flowers of the Jeolla-do province in Korea (호남 지역 꽃으로부터 야생효모 Aureobasidium속 분리 및 동정)

  • Kim, Jeong-Seon;Lee, Miran;Song, Mi Young;Kwon, Soon-Wo;Kim, Soo-Jin;Hong, Seung-Beom;Park, Byeong-Yong;Yun, Bong Sik
    • The Korean Journal of Mycology
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    • v.46 no.4
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    • pp.415-425
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    • 2018
  • To study the characteristics of yeasts, 433 strains of the genus Aureobasidium were isolated from the flowers collected from Jeolla-do in Korea, and the diversity of the strains was confirmed through molecular phylogenetic and morphological analyses. Based on phylogenetic analysis of LSU rDNA seguences, the Aureobasidium strains from the Jeolla-do province were classified into six groups. The dominant species of flower-derived yeasts were Groups A and D. Since Groups B, E, and F were found only in Jeollanam-do, we can infer that the Aureobasidium is distributed more widely in Jeollanam-do than in the Jeollabuk-do province. Through LSU and ITS rDNA sequence analyses, Group A was identified as A. pullulans, Group B as A. melanogenum, and Group F as a putative new species of Aureobasidium. Groups C, D, and E do not completely match with A. leucospermi, A. namibiae, or A. subglaciale by LSU or ITS rDNA analysis but are closely related to those species. Comparisons of colony morphology are likely to be more helpful in distinguishing Groups C and D. The results of this study can provide useful characteristics for future studies of the genus Aureobasidium.

Strain Identification of Xanthomonas oryzae by Bacteriophages and their Distribution in Korea (Bacteriophage에 의한 벼흰빛잎마름병균의 계통분류 및 그 분포에 관한 연구)

  • Cho Yong Sup;Park Chang Seuk;Choi Yong Chul;Lee Kyung Hee
    • Korean journal of applied entomology
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    • v.11 no.2
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    • pp.85-89
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    • 1972
  • Fifty-one isolates of Xanthomonas oryzae collected from all over the Korean paddy field were classified as the eight different strains by using four different bacteriophage types. Strain-F was the most prevalent form and strain-H,C, and A followed the strain-F, respectively. Strain-D, however, had not found even single isolate although the strain·D is the most prevalent form at Japan and southern countries of Asia. There was no corelation between the type of strains and the area front which the strain had been collected. Six different types of strains were isolated from IR 667 varieties whereas the three strains were maximum that could isolated from single variety other than IR 667.

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Whitening Effect of Fagopyrum tataricum Extract (쓴메밀 추출물의 미백 개선 효과)

  • Han, Na Kyeong;Park, Chang Min;Kwon, Ju Chan;Joung, Min Seok;Choi, Jong Wan
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.40 no.2
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    • pp.179-186
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    • 2014
  • This study was performed to DPPH radical scavenging activity, ABTS radical scavenging activity, tyrosinase inhibition activity and intracellular melanin synthesis inhibition to verify the whitening effect of Fagopyrum tataricum (bitter buckwheat) extract as contrasted with Fagopyrum esculentum (sweet buckwheat) extract. F. tataricum extract in consequence showed higher antioxidant activities, tyrosinase inhibition activity and melanin synthesis inhibition compared with F. esculentum extract. We investigated skin bright value during 8 weeks after induction of pigmentation in human skin from UV irradiation. In result, we obtained statistically a significant skin whitening effect from visual and mechanical evaluation. Accordingly, F. tataricum extract is expected to be high availability as functional cosmetic material for skin whitening.

A New Strength Equation of Concrete by Penetration Resistance Test (관입시험법에 의한 콘크리트의 강도 추정)

  • Park Song-chul;Yoo Jae-Eun;Kim Min-Su;Kwon Young-Wung
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.125-128
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    • 2004
  • This study concerns the new estimated strength equation of concrete by penetration test. There are not only few estimate strength equations of concrete, but also many problems to apply them because of time, cost, easiness, structural damage, reliability and so on. In this study, there performed a series of penetration test with in 730days' concrete structures and proposed equations as follows; $$Linear\;:\;f_{ck}=2.95d-80.0(r^2= 69.8\%)$$ $$Quadratic\;:\;f_{ck}=0.204d^2-12.15d+193.2(r^2=83.6\%)$$ here, fck : Estimated compressive strength of concrete by MPa d: exposed probe length by mm.

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HADAMARD-TYPE FRACTIONAL CALCULUS

  • Anatoly A.Kilbas
    • Journal of the Korean Mathematical Society
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    • v.38 no.6
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    • pp.1191-1204
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    • 2001
  • The paper is devoted to the study of fractional integration and differentiation on a finite interval [a, b] of the real axis in the frame of Hadamard setting. The constructions under consideration generalize the modified integration $\int_{a}^{x}(t/x)^{\mu}f(t)dt/t$ and the modified differentiation ${\delta}+{\mu}({\delta}=xD,D=d/dx)$ with real $\mu$, being taken n times. Conditions are given for such a Hadamard-type fractional integration operator to be bounded in the space $X^{p}_{c}$(a, b) of Lebesgue measurable functions f on $R_{+}=(0,{\infty})$ such that for c${\in}R=(-{\infty}{\infty})$, in particular in the space $L^{p}(0,{\infty})\;(1{\le}{\le}{\infty})$. The existence almost every where is established for the coorresponding Hadamard-type fractional derivative for a function g(x) such that $x^{p}$g(x) have $\delta$ derivatives up to order n-1 on [a, b] and ${\delta}^{n-1}[x^{\mu}$g(x)] is absolutely continuous on [a, b]. Semigroup and reciprocal properties for the above operators are proved.

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