• Title/Summary/Keyword: the properties of derivative

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A Topological Derivative Based Non-Iterative Electromagnetic Imaging of Perfectly Conducting Cracks

  • Ma, Yong-Ki;Park, Won-Kwang
    • Journal of electromagnetic engineering and science
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    • v.12 no.1
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    • pp.128-134
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    • 2012
  • In this manuscript, we consider electromagnetic imaging of perfectly conducting cracks completely hidden in a homogeneous material via boundary measurements. For this purpose, we carefully derive a topological derivative formula based on the asymptotic expansion formula for the existence of a perfectly conducting inclusion with a small radius. With this, we introduce a topological derivative based imaging algorithm and discuss its properties. Various numerical examples with noisy data show the effectiveness and limitations of the imaging algorithm.

Fluid viscous device modelling by fractional derivatives

  • Gusella, V.;Terenzi, G.
    • Structural Engineering and Mechanics
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    • v.5 no.2
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    • pp.177-191
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    • 1997
  • In the paper, a fractional derivative Kelvin-Voigt model describing the dynamic behavior of a special class of fluid viscous dampers, is presented. First of all, in order to verify their mechanical properties, two devices were tested the former behaving as a pure damper (PD device), whereas the latter as an elastic-damping device (ED device). For both, quasi-static and dynamic tests were carried out under imposed displacement control. Secondarily, in order to describe their cyclical behavior, a model composed by an elastic and a damping element connected in parallel was defined. The elastic force was assumed as a linear function of the displacement whereas the damping one was expressed by a fractional derivative of the displacement. By setting an appropriate numerical algorithm, the model parameters (fractional derivative order, damping coefficient and elastic stiffness) were identified by experimental results. The estimated values allowed to outline the main parameter properties on which depend both the elastic as well as the damping behavior of the considered devices.

Hair-growth Effect of Chrysin 7-O-cyclopropanecarboxylate (크라이신 사이크로푸로판카복실레이트의 육모효과)

  • 장지면;이명철;신준수;정재훈;김양배;김박광
    • Biomolecules & Therapeutics
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    • v.9 no.1
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    • pp.15-19
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    • 2001
  • The derivative of chrysin 7-O-cyclopropanecarboxylate was synthesized by condensing cyclopropanecarboxylic acid with chrysin in organic solvent, and its structure was identified by NMR, MS, UV IR etc. We also investigated the physico-chemical properties, anti-diabetic effect and set up the quantitative analytical method of this compound. The correlation coefficient of calibration curve on this compound was approximately 0.9985 by absorption spectrophotometry. And, this study was carried out to investigate the hair-growth effect of chrysin derivative to the black mouse (C57BL/6). When this derivative in ethanol solution was administered to the back of mouse by method of skin paste, this derivative promoted the hair growth of mouse.

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STRONG DIFFERENTIAL SUBORDINATION AND SUPERORDINATION OF NEW GENERALIZED DERIVATIVE OPERATOR

  • OSHAH, ANESSA;DARUS, MASLINA
    • Korean Journal of Mathematics
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    • v.23 no.4
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    • pp.503-519
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    • 2015
  • In this work, certain classes of admissible functions are considered. Some strong dierential subordination and superordination properties of analytic functions associated with new generalized derivative operator $B^{{\mu},q,s}_{{\lambda}_1,{\lambda}_2,{\ell},d}$ are investigated. New strong dierential sandwich-type results associated with the generalized derivative operator are also given.

Studies on the Reinforcement Treatment of Aged Hanji Using Cellulose Derivative Solutions (셀룰로오스 유도체 용액을 이용한 열화 한지의 강도보강 처리에 관한 연구)

  • Kang, Kwang-Ho;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.2
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    • pp.40-48
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    • 2011
  • To build up the conservativeness of aged paper heritages, the strength reinforcement treatment using various cellulose derivative solutions was considered. Hand-made Hanji prepared by traditional papermaking technique was firstly simulated in order to modify the overall of paper properties like aged paper heritages by accelerated ageing treatment at $150^{\circ}C$ for 24 hours, and then the ageing stability of Hanji was verified through the secondary accelerated ageing at $150^{\circ}C$ for 12 hours. The physical properties of aged Hanji were improved by applying with cellulose derivative solutions. The ageing stability for physical, optical (L, brightness, opacity, yellowness) and chemical (oxidation index, degree of polymerization) properties of aged Hanji treated with all kinds of cellulose derivative solutions was also good compared to those of untreated samples, especially using MC solution. Therefore, it was that a kind of MC solution would be well-suited for the strength reinforcement treatment of aged paper heritages.

Transient Absorption Spectra of Phenothiazine Derivative in the Vesicle System Containing Ru$^{2+}$ Complex as a Sensitizer

  • Park, Yong-Tae;Kim, Young-Doo;Burkhart, Richard D.;Caldwell, Norris J.
    • Bulletin of the Korean Chemical Society
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    • v.9 no.2
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    • pp.84-87
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    • 1988
  • The Photophysical and photochemical properties of Ruthenium bipyridine with two long hydrocarbon chains, $[Ru(bipy)_2(dhbipy)]^{2+}$ and transient phenothiazine derivative cation radical $(PTD^+)$ in the cationic vesicle were studied. Transient absorption spectra of cation radical of phenothiazine derivative in the vesicle system containing the $Ru^{2+}$ complex, $[Ru(bipy)_2(dhbipy)]^{2+}$, (1) as sensitizer and phenothiazine derivative as electron donor was observed by XeCl excimer laser photolysis system. Thus the excited ruthenium complex would be quenched by phenothiazine derivative(PTD) reductively in the vesicle system. The quenching rate constant($K_Q$) of $Ru^{2+}$ with two long hydrocarbon chains in the vesicle by PTD was $9.6{\times}10^8M^{-1}S^{-1}$. The absorption decay kinetics showed that lifetime of phenothiazine derivative cation radical is a value in the 4-8m sec range.

LIPSCHITZ CLASS, GROWTH OF DERIVATIVE AND UNIFORMLY JOHN DOMAINS

  • Kim, Ki-Won
    • East Asian mathematical journal
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    • v.19 no.2
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    • pp.291-303
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    • 2003
  • A result of Hardy and Littlewood relates Holder continuity of analytic functions in the unit disk with a bound on the derivative. Gehring and Martio extended this result to the class of uniform domains. In this paper we obtain a similar result to the class of uniformly John domains in terms of the inner diameter metric. We give several properties of a domain with the property. Also we show some results on the Holder continuity of conjugate harmonic functions in the above domains.

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Neighborhood Properties for Certain Subclasses of Analytic Functions of Complex Order with Negative Coefficients

  • Bulut, Serap
    • Kyungpook Mathematical Journal
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    • v.54 no.2
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    • pp.211-220
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    • 2014
  • In the present investigation, by making use of the familiar concept of neighborhoods of analytic and multivalent functions, we prove several inclusion relations associated with the (n, ${\delta}$)-neighborhoods of certain subclasses of analytic functions of complex order, which are introduced here by means of the Al-Oboudi derivative. Several special cases of the main results are mentioned.

THE SPACE-TIME FRACTIONAL DIFFUSION EQUATION WITH CAPUTO DERIVATIVES

  • HUANG F.;LIU F.
    • Journal of applied mathematics & informatics
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    • v.19 no.1_2
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    • pp.179-190
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    • 2005
  • We deal with the Cauchy problem for the space-time fractional diffusion equation, which is obtained from standard diffusion equation by replacing the second-order space derivative with a Caputo (or Riemann-Liouville) derivative of order ${\beta}{\in}$ (0, 2] and the first-order time derivative with Caputo derivative of order ${\beta}{\in}$ (0, 1]. The fundamental solution (Green function) for the Cauchy problem is investigated with respect to its scaling and similarity properties, starting from its Fourier-Laplace representation. We derive explicit expression of the Green function. The Green function also can be interpreted as a spatial probability density function evolving in time. We further explain the similarity property by discussing the scale-invariance of the space-time fractional diffusion equation.

HIGHER ORDER CLOSE-TO-CONVEX FUNCTIONS ASSOCIATED WITH RUSCHEWEYH DERIVATIVE OPERATOR

  • NOOR, KHALIDA INAYAT;SHAH, SHUJAAT ALI
    • Journal of applied mathematics & informatics
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    • v.39 no.1_2
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    • pp.133-143
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    • 2021
  • The purpose of this paper is to introduce and study certain subclasses of analytic functions by using Ruscheweyh derivative operator. We discuss various of interesting properties such as, necessary condition, arc length problem and growth rate of coefficient of newly defined class. Also rate of growth of Hankel determinant will be estimated.