• 제목/요약/키워드: Estimate equation

검색결과 1,530건 처리시간 0.029초

A New Accurate Equation for Estimating the Baseline for the Reversal Peak of a Cyclic Voltammogram

  • Oh, Sung-Hoon;Chang, Byoung-Yong
    • Journal of Electrochemical Science and Technology
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    • 제7권4호
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    • pp.293-297
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    • 2016
  • Here we propose a new equation by which we can estimate the baseline for measuring the peak current of the reverse curve in a cyclic voltammogram. A similar equation already exists, but it is a linear algebraic equation that over-simplifies the voltammetric curve and may cause unpredictable errors when calculating the baseline. In our study, we find a quadratic algebraic equation that acceptably reflects the complexity included in a voltammetric curve. The equation is obtained from a laborious numerical analysis of cyclic voltammetry simulations using the finite element method, and not from the closed form of the mathematical equation. This equation is utilized to provide a virtual baseline current for the reverse peak current. We compare the results obtained using the old linear and new quadratic equations with the theoretical values in terms of errors to ascertain the degree to which accuracy is improved by the new equation. Finally, the equations are applied to practical cyclic voltammograms of ferricyanide in order to confirm the improved accuracy.

HIGHER EIGENVALUE ESTIMATE ON MANIFOLD

  • Kim, Bang-Ok;Robert Gulliver
    • 대한수학회논문집
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    • 제13권3호
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    • pp.579-587
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    • 1998
  • In this paper we will estimate the lower bound of k-th Dirichlet eigenvalue $ \lambda_{k}$ / of Laplace equation on bounded domain in sphere.

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A Simple Estimation of Relative Risk

  • Park, Hyo-Il;Hong, Seung-Man
    • Communications for Statistical Applications and Methods
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    • 제14권2호
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    • pp.317-327
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    • 2007
  • In this paper, we propose a simple estimate of relative risk based on a functional equation. We derive the asymptotic normality with a restricted condition. Then we discuss some interesting features as concluding remarks. Finally we comment briefly about application of the estimate to the testing problems and compare our estimate with that of Begun through simulation study.

NOTE ON LOCAL ESTIMATES FOR WEAK SOLUTION OF BOUNDARY VALUE PROBLEM FOR SECOND ORDER PARABOLIC EQUATION

  • Choi, Jongkeun
    • 대한수학회보
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    • 제53권4호
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    • pp.1123-1148
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    • 2016
  • The aim of this note is to provide detailed proofs for local estimates near the boundary for weak solutions of second order parabolic equations in divergence form with time-dependent measurable coefficients subject to Neumann boundary condition. The corresponding parabolic equations with Dirichlet boundary condition are also considered.

MANN-ITERATION PROCESS TO THE SOLUTION OF $y=x+Tx$ FOR AN ACDRETIVE OPERATOR T IN SOME BANACH SPACES

  • Park, Jong-An
    • 대한수학회논문집
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    • 제9권4호
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    • pp.819-823
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    • 1994
  • If H is a Hilbert space, then an operator $T : D(T) \subset H \to H$ is said to be monotone if $$ (x-y, Tx-Ty) \geq 0$$ for any x, y in D(T). Many authors [1], [4] obtained the existence theorem for the equation $y = x + Tx$ for x, given an element y in H and a monotone operator T. On the other hand some iterative methods were applied to the approximations for the solution of the above equation [6], [8]. For example Bruck [2] obtained the iterative solution of the above equation with an explicit error estimate as follows.

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STABILITY FOR A VISCOELASTIC PLATE EQUATION WITH p-LAPLACIAN

  • Park, Sun Hye
    • 대한수학회보
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    • 제52권3호
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    • pp.907-914
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    • 2015
  • In this paper, we consider a viscoelastic plate equation with p-Laplacian $u^{{\prime}{\prime}}+{\Delta}^2u-div({\mid}{\nabla}u{\mid}^{p-2}{\nabla}u)+{\sigma}(t){\int}_{0}^{t}g(t-s){\Delta}u(s)ds-{\Delta}u^{\prime}=0$. By introducing suitable energy and Lyapunov functionals, we establish a general decay estimate for the energy, which depends on the behavior of both ${\sigma}$ and g.

A STUDY ON THE EFFECTIVE ALGORITHMS BASED ON THE WEGMANN'S METHOD

  • Song, Eun-Jee
    • Journal of applied mathematics & informatics
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    • 제20권1_2호
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    • pp.595-602
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    • 2006
  • Determinations of conformal map from the unit disk onto a Jordan region are reduced to solve the Theodorsen equation which is an integral equation for the boundary correspondence function. Among numerical conformal maps the Wegmann's method is well known as a Newton efficient one for solving Theodorsen equation. However this method has not so wide class of convergence. We proposed as an improved method for convergence by applying a low frequency filter to the Wegmann's method. In this paper, we investigate error analysis and propose an automatic algorithm based on this analysis.

FINITE ELEMENT SCHEME FOR THE VISCOUS CAHN-HILLIARD EQUATION WITH A NONCONSTANT GRADIENT ENERGY COEFFICIENT

  • CHOO S. M.;KIM Y. H.
    • Journal of applied mathematics & informatics
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    • 제19권1_2호
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    • pp.385-395
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    • 2005
  • A finite element scheme is considered for the viscous Cahn-Hilliard equation with the nonconstant gradient energy coefficient. The scheme inherits energy decay property and mass conservation as for the classical solution. We obtain the corresponding error estimate using the extended Lax-Richtmyer equivalence theorem.

철근콘크리트 보-기둥 접합부의 전단강도 평가 (Shear Strength Estimate of Reinforced Concrete Beam-Column Joints)

  • 채희대;이정윤
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.389-392
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    • 2004
  • An accurate and rational analytical proposal for determining the shear strengths of interior beam-column joints is presented in this paper. The proposed equation is derived using a compatiblity aided truss model theory. The accuracy of the proposed equation was checked by comparing calculated shear strength of joints with experimental results reported papers in literature. The comparison showed that the proposed equation predicted the experimental shear strength of joints with reasonable agreement.

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