• Title/Summary/Keyword: w-continuous function

Search Result 42, Processing Time 0.027 seconds

Effect of Surfactant Micelles on Oxidation in W/O/W Multiple Emulsion (Surfactant micelle이 W/O/W multiple emulsion의 산화에 미치는 영향)

  • Cha, Woen-Seup;Cho, Young-Je
    • Journal of Life Science
    • /
    • v.20 no.11
    • /
    • pp.1611-1616
    • /
    • 2010
  • The purpose of this research was to determine the effect of surfactant micelles on lipid oxidation in W/O/W multiple emulsions. The content of ferric irons and hydroperoxide in the continuous phase in W/O/W multiple emulsions was measured as a function of Brij micelle. The concentration of ferric iron and hydroperoxide in the continuous phase increased with increased storage time (1~6 days). Lipid oxidation rates, as determined by the formation of lipid hydroperoxides, TBARs and headspace hexanal, in the W/O/W multiple emulsions containing ferric iron decreased when 3% surfactant micelles were exceeded. These results indicate that excess surfactant micelles could alter the physical location and prooxidant activity of iron in W/O/W multiple emulsions.

Fourier transformations of $W^{\Phi}$-spaces

  • Kim, Sung-Ki;Kim, Dohan
    • Bulletin of the Korean Mathematical Society
    • /
    • v.34 no.3
    • /
    • pp.483-489
    • /
    • 1997
  • The $W^\phi$-spaces generalizing the $W^p$-spaces due to Pathak and Upadhyay are investigated and the Fourier transformations on these spaces are continuous.

  • PDF

ON CHARACTERIZATIONS OF THE NORMAL DISTRIBUTION BY INDEPENDENCE PROPERTY

  • LEE, MIN-YOUNG
    • Journal of applied mathematics & informatics
    • /
    • v.35 no.3_4
    • /
    • pp.261-265
    • /
    • 2017
  • Let X and Y be independent identically distributed nondegenerate random variables with common absolutely continuous probability distribution function F(x) and the corresponding probability density function f(x) and $E(X^2)$<${\infty}$. Put Z = max(X, Y) and W = min(X, Y). In this paper, it is proved that Z - W and Z + W or$(X-Y)^2$ and X + Y are independent if and only if X and Y have normal distribution.

FIRST PASSAGE PROBLEM FOR WIENER PATHS CROSSING DIFFERENTIABLE CURVES

  • Jang, Yu-Seon;Kim, Sung-Lai;Kim, Sung-Kyun
    • Journal of applied mathematics & informatics
    • /
    • v.19 no.1_2
    • /
    • pp.475-484
    • /
    • 2005
  • Let W(t) be a Wiener path, let $\xi\;:\;[0,\;{\infty})\;\to\;\mathbb{R}$ be a continuous and increasing function satisfying $\xi$(0) > 0, let $$T_{/xi}=inf\{t{\geq}0\;:\;W(t){\geq}\xi(t)\}$$ be the first-passage time of W over $\xi$, and let F denote the distribution function of $T_{\xi}$. Then the first passage problem has a unique continuous solution as following $$F(t)=u(t)+{\sum_{n=1}^\infty}\int_0^t\;H_n(t,s)u(s)ds$$, where $$u(t)=2\Psi(\xi(t)/\sqrt{t})\;and\;H_1(t,s)=d\Phi\;(\{\xi(t)-\xi(s)\}/\sqrt{t-s})/ds\;for\;0\;{\leq}\;s.

Some Remarks on the s-plane to w-plane Correlations of w-transform (w-변환의 s와 w영역간의 관계에 대한 유의 성질)

  • Jin, Lihua;Kim, Young-Chol
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.61 no.1
    • /
    • pp.117-124
    • /
    • 2012
  • In this paper, we present some remarks on the correlations between s and w domains when a discrete-time transfer function is converted from z-plane by using the w-transform. With time response specifications, when a digital filter or controller is designed in z-plane, the w-transform is useful for the purpose if only the w-transformed system closely approximates to the continuous-time system. It will be shown that the approximation is accomplished only in the specific region depending on sampling time. Also, it is noted that such an approximation should be carefully dealt with for the case where a discrete-time reference transfer function is synthesized for the use of direct digital design.

Effect of Surfactant Micelles on Lipid Oxidation in Oil-in-water Emulsion Containing Soybean Oil (Surfactant micelle이 수중유적형 유화계내의 대두유 산화에 미치는 영향)

  • Cho, Young-Je;Chun, Sung-Sook;Decker, Eric A.
    • Korean Journal of Food Science and Technology
    • /
    • v.34 no.5
    • /
    • pp.770-774
    • /
    • 2002
  • Effect of surfactant micelles on lipid oxidation was determined in soybean oil-in-water (O/W) emulsions. The concentration of ferric irons to continuous phase in the O/W emulsions was measured as a function of various Brij type and concentrations. The concentration of ferric iron in the continuous phase increased with increasing surfactant micelles concentration $(0.5{\sim}2.0%)$ and storage time $(1{\sim}7\;days)$. At pH 3.0, the concentration of continuous phase iron was higher than at pH 7.0. Lipid oxidation rates, as determined by the formation of lipid hydroperoxides and headspace hexanal, in the O/W emulsions containing ferric iron decreased with increasing surfactant micelle concentration $(0.5{\sim}2.0%)$. These results indicate that surfactant micelles concentration could alter the physical location and prooxidant activity of iron in soybean O/W emulsions.

Design and Implementation of a Control Language for Continuous Process Automation : Function Block Diagram Approach (연속공정 자동화를 위한 Function block diagram형 제어언어의 설계 및 구현)

  • Cho, Y. J.;Yoom, T. W.;Lee, J. S.;Oh, S. R.;Choy, I.;Kim, K. B.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1991.10a
    • /
    • pp.226-231
    • /
    • 1991
  • A graphic control language using function block diagram approach is designed and implemented, applicable to real-time control for continuous process automation system. The procedure implementing the control language is composed of three parts, editor, compiler, and executer. The editor generates the control algorithm file, which contains function block information in the text form, by menu-driven method on the color graphic screen. The compiler translates the contents of the control algorithm file to machine codes and their related data. Then, the executer generates a task that makes the machine codes executed at every sampling period in the target processor. The validity of the concept in its design and implementaion is assured by on-line simulation in the multi-function controller designed for continuous process automation.

  • PDF

GENERALIZED SOLUTIONS OF IMPULSIVE CONTROL SYSTEMS CORRESPONDING TO CONTROLS OF BOUNDED VARIATION

  • Shin, Chang-Eon
    • Journal of the Korean Mathematical Society
    • /
    • v.34 no.3
    • /
    • pp.581-598
    • /
    • 1997
  • This paper is concerned with the impulsive control problem $$ \dot{x}(t) = f(t, x) + g(t, x)\dot{u}(t), t \in [0, T], x(0) = \overline{x}, $$ where u is a possibly discontinuous control function of bounded variation, $f : R \times R^n \mapsto R^n$ is a bounded and Lipschitz continuous function, and $g : R \times R^n \mapsto R^n$ is continuously differentiable w.r.t. the variable x and satisfies $\mid$g(t,\cdot) - g(s,\cdot)$\mid$ \leq \phi(t) - \phi(s)$, for some increasing function $\phi$ and every s < t. We show that the map $u \mapsto x_u$ is Lipschitz continuous when u ranges in the set of step functions whose total variations are uniformly bounded, where $x_u$ is the solution of the impulsive control system corresponding to u. We also define the generalized solution of the impulsive control system corresponding to a measurable control functin of bounded variation.

  • PDF

Continuous Variable Structure Controller for the Tracking Control of PMSM (영구자석 동기전동기의 위치 추적 제어를 위한 연속 가변 구조 제어기)

  • Hong, Chan-Ho;Chung, Se-Kyo;Lee, Jung-Hoon;Youn, Myung-Joong
    • Proceedings of the KIEE Conference
    • /
    • 1995.11a
    • /
    • pp.261-263
    • /
    • 1995
  • The continuous sliding mode controller with disturbance observer for the tracking control of permanent magnet synchronous motor(PMSM) is presented. In spite of the robust performance of variable structure control, there exists an undesirable chattering problem, which may be very harmful in some cases. To alleviate the problem, continuous sliding mode controller with continuous saturation function is proposed and also the prescribed performance can be obtained by efficient compensation of disturbance. Experimental results using 7.5 kW, 4000 rpm motor which is controlled by TMS320C30 DSP, are shown to demonstrate the usefulness of the proposed algorithm.

  • PDF

ON EQUIVALENT NORMS TO BLOCH NORM IN ℂn

  • Choi, Ki Seong
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.19 no.4
    • /
    • pp.325-334
    • /
    • 2006
  • For $f{\in}L^2(B,d{\nu})$, ${\parallel}f{\parallel}_{BMO}=\widetilde{{\mid}f{\mid}^2}(z)-{\mid}{\tilde{f}}(z){\mid}^2$. For f continuous on B, ${\parallel}f{\parallel}_{BO}=sup\{w(f)(z):z{\in}B\}$ where $w(f)(z)=sup\{{\mid}f(z)-f(w){\mid}:{\beta}(z,w){\leq}1\}$. In this paper, we will show that if $f{\in}BMO$, then ${\parallel}f{\parallel}_{BO}{\leq}M{\parallel}f{\parallel}_{BMO}$. We will also show that if $f{\in}BO$, then ${\parallel}f{\parallel}_{BMO}{\leq}M{\parallel}f{\parallel}_{BO}^2$. A homomorphic function $f:B{\rightarrow}{\mathbb{C}}$ is called a Bloch function ($f{\in}{\mathcal{B}}$) if ${\parallel}f{\parallel}_{\mathcal{B}}=sup_{z{\in}B}\;Qf(z)$<${\infty}$. In this paper, we will show that if $f{\in}{\mathcal{B}}$, then ${\parallel}f{\parallel}_{BO}{\leq}{\parallel}f{\parallel}_{\mathcal{B}}$. We will also show that if $f{\in}BMO$ and f is holomorphic, then ${\parallel}f{\parallel}_{\mathcal{B}}^2{\leq}M{\parallel}f{\parallel}_{BMO}$.

  • PDF