• Title/Summary/Keyword: a priori

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ON THE APPLICATION OF MIXED FINITE ELEMENT METHOD FOR A STRONGLY NONLINEAR SECOND-ORDER HYPERBOLIC EQUATION

  • Jiang, Ziwen;Chen, Huanzhen
    • Journal of applied mathematics & informatics
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    • v.5 no.1
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    • pp.23-40
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    • 1998
  • Mixed finite element method is developed to approxi-mate the solution of the initial-boundary value problem for a strongly nonlinear second-order hyperbolic equation in divergence form. Exis-tence and uniqueness of the approximation are proved and optimal-order $L\infty$-in-time $L^2$-in-space a priori error estimates are derived for both the scalar and vector functions approximated by the method.

SVM-Guided Biplot of Observations and Variables

  • Huh, Myung-Hoe
    • Communications for Statistical Applications and Methods
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    • v.20 no.6
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    • pp.491-498
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    • 2013
  • We consider support vector machines(SVM) to predict Y with p numerical variables $X_1$, ${\ldots}$, $X_p$. This paper aims to build a biplot of p explanatory variables, in which the first dimension indicates the direction of SVM classification and/or regression fits. We use the geometric scheme of kernel principal component analysis adapted to map n observations on the two-dimensional projection plane of which one axis is determined by a SVM model a priori.

GLOBAL AXISYMMETRIC SOLUTIONS TO THE 3D NAVIER-STOKES-POISSON-NERNST-PLANCK SYSTEM IN THE EXTERIOR OF A CYLINDER

  • Zhao, Jihong
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.3
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    • pp.729-744
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    • 2021
  • In this paper we prove global existence and uniqueness of axisymmetric strong solutions for the three dimensional electro-hydrodynamic model based on the coupled Navier-Stokes-Poisson-Nernst-Planck system in the exterior of a cylinder. The key ingredient is that we use the axisymmetry of functions to derive the Lp interpolation inequalities, which allows us to establish all kinds of a priori estimates for the velocity field and charged particles via several cancellation laws.

On analysis of nonlinear impedance force control for robot manipulators (로봇의 비선형 임피던스 힘제어에 대한 연구)

  • Jung, Seul;Lee, Ji-Hong
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.560-563
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    • 1997
  • The conventional impedance control has been known to have the following problems: it has lack of specifying force directly and unknown environment stiffness has to be known priori in order to specify the reference trajectory. In this paper, new impedance force control that can control a desired force directly under unknown stiffness is proposed. A new nonlinear impedance function is developed based on estimation of unknown stiffness from force and position measurements. The nonlinear characteristics of the proposed impedance function are analyzed based on unknown environment position. Simulation studies with robot manipulator are carried out to test analytical results.

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GLOBAL SOLUTIONS TO CHEMOTAXIS-HAPTOTAXIS TUMOR INVASION SYSTEM WITH TISSUE RE-ESTABLISHMENT

  • Kang, Ensil;Lee, Jihoon
    • Journal of the Chungcheong Mathematical Society
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    • v.28 no.1
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    • pp.161-172
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    • 2015
  • In this paper, we consider the chemotaxis-haptotaxis model of tumor invasion with the proliferation and tissue re-establishment term in dimensions one and two. We show the global in time existence of a unique classical solution for the the model in two dimensional spatial domain without any restrictions on the coefficients.

Fuzzy Neural Newtork Pattern Classifier

  • Kim, Dae-Su;Hun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.1 no.3
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    • pp.4-19
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    • 1991
  • In this paper, we propose a fuzzy neural network pattern classifier utilizing fuzzy information. This system works without any a priori information about the number of clusters or cluster centers. It classifies each input according to the distance between the weights and the normalized input using Bezdek's [1] fuzzy membership value equation. This model returns the correct membership value for each input vector and find several cluster centers. Some experimental studies of comparison with other algorithms will be presented for sample data sets.

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Restoration of Chest X-ray Image Using Dual Projection Filter (이중 프로젝션 필터를 이용한 흉부 X-선 영상의 복원)

  • 이태수;민병구
    • Journal of Biomedical Engineering Research
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    • v.13 no.1
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    • pp.25-32
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    • 1992
  • A new restoration method of chest X -ray image (dual project filter) was proposed to improve SNR(signal to noise ratio) characteristics. In this method, a priori Information of system and anatomical structure and statistics of projected object are used in the design of filter. Dual projection filter varies its parameters, adapting to the local regions of chest(lung region, mediasternum, subdiaphragm) and the structure of chest (bone, tissue, blood vessel, bronchia). The performance of Dual Projection Filter was 0.1-0.2dB better than Dual Sensor Wiener Filter, which was used for initial estimate of Dual Porjection Filter.

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Force-finding of Tensegrity Structure using Optimization Technique

  • Lee, Sang Jin
    • Architectural research
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    • v.17 no.1
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    • pp.31-40
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    • 2015
  • A simple force-finding process based on an optimization technique is proposed for tensegrity structures. For this purpose, the inverse problem of form-finding process is formulated. Therefore, the position vector of nodes and element connectivity information are provided as priori. Several benchmark tests are carried out to demonstrate the performance of the present force-finding process. In particular, the force density distributions of simplex tensegrity are thoroughly investigated with the important parameters such as the radius, height and twisting angle of simplex tensegrity. Finally, the force density distribution of arch tensegrity is produced by using the present force-finding process for a future reference solution.

A FOURTH-ORDER ACCURATE FINITE DIFFERENCE SCHEME FOR THE EXTENDED-FISHER-KOLMOGOROV EQUATION

  • Kadri, Tlili;Omrani, Khaled
    • Bulletin of the Korean Mathematical Society
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    • v.55 no.1
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    • pp.297-310
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    • 2018
  • In this paper, a nonlinear high-order difference scheme is proposed to solve the Extended-Fisher-Kolmogorov equation. The existence, uniqueness of difference solution and priori estimates are obtained. Furthermore, the convergence of the difference scheme is proved by utilizing the energy method to be of fourth-order in space and second-order in time in the discrete $L^{\infty}-norm$. Some numerical examples are given in order to validate the theoretical results.