• 제목/요약/키워드: Polynomial Method

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Q-Polynomial을 이용한 Korsch 망원경의 비구면 공차 분석 방법 연구 (Study of the Analysis Method for the Aspherical Tolerance of a Korsch Telescope Using a Q Polynomial)

  • 전원균;이한율;이상민;김기환;박승한;정미숙
    • 한국광학회지
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    • 제31권6호
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    • pp.328-333
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    • 2020
  • 본 논문에서는 Q-polynomial을 이용한 Korsch 망원경의 비구면 반사경 공차 분석을 진행하였다. 고해상도 인공위성의 비구면 반사경은 고정밀 제작이 요구되어 품질을 평가하기 위한 공차 분석이 중요하다. 따라서 비구면을 각 계수항들이 독립적인 Q-polynomial로 표현하고 Korsch 망원경 광학계의 공차 분석을 진행하였다. 또한 비구면 반사경에 형상 오차를 Zernike fringe sag로 부여하여 공차 분석하고 두 결과를 비교하여 Q-polynomial으로도 공차 분석할 수 있음을 확인하였다.

영구자석의 overhang 길이 및 skew 효과를 고려한 LSM 추력함수 도출 (A Elicitation of Polynomial Equation of Thrust Coefficient for Linear Synchronous Motor by Experimental Design Method)

  • 장기봉;표세호;김규탁
    • 전기학회논문지
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    • 제58권6호
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    • pp.1105-1109
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    • 2009
  • This paper deals with a polynomial thrust equation of a permanent magnet linear synchronous motor that is considered by a skew and overhang effects of permanent magnet. The skew length, the overhang length, the width and height of permanent magnet, the teeth length and air-gap length which effect to the flux density of air-gap are selected as variables of the polynomial thrust equation. Polynomial thrust equation is elicited by the 6 parameters. The results are satisfied that the values by polynomial thrust equation are compared ones by using 3-dimensional finite element analysis and experiment.

퍼지 활성 노드를 가진 퍼지 다항식 뉴럴 네트워크 (Fuzzy Polynomial Neural Networks with Fuzzy Activation Node)

  • 박호성;김동원;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2946-2948
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    • 2000
  • In this paper, we proposed the Fuzzy Polynomial Neural Networks(FPNN) model with fuzzy activation node. The proposed FPNN structure is generated from the mutual combination of PNN(Polynomial Neural Networks) structure and fuzzy inference system. The premise of fuzzy inference rules defines by triangular and gaussian type membership function. The fuzzy inference method uses simplified and regression polynomial inference method which is based on the consequence of fuzzy rule expressed with a polynomial such as linear, quadratic and modified quadratic equation are used. The structure of FPNN is not fixed like in conventional Neural Networks and can be generated. The design procedure to obtain an optimal model structure utilizing FPNN algorithm is shown in each stage. Gas furnace time series data used to evaluate the performance of our proposed model.

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하이브리드 퍼지뉴럴네트워크의 알고리즘과 구조 (Algorithm and Architecture of Hybrid Fuzzy Neural Networks)

  • 박병준;오성권;김현기
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.372-372
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    • 2000
  • In this paper, we propose Neuro Fuzzy Polynomial Networks(NFPN) based on Polynomial Neural Network(PNN) and Neuro-Fuzzy(NF) for model identification of complex and nonlinear systems. The proposed NFPN is generated from the mutually combined structure of both NF and PNN. The one and the other are considered as the premise part and consequence part of NFPN structure respectively. As the premise part of NFPN, NF uses both the simplified fuzzy inference as fuzzy inference method and error back-propagation algorithm as learning rule. The parameters such as parameters of membership functions, learning rates and momentum coefficients are adjusted using genetic algorithms. As the consequence part of NFPN, PNN is based on Group Method of Data Handling(GMDH) method and its structure is similar to Neural Networks. But the structure of PNN is not fixed like in conventional Neural Networks and self-organizing networks that can be generated. NFPN is available effectively for multi-input variables and high-order polynomial according to the combination of NF with PNN. Accordingly it is possible to consider the nonlinearity characteristics of process and to get better output performance with superb predictive ability. In order to evaluate the performance of proposed models, we use the nonlinear function. The results show that the proposed FPNN can produce the model with higher accuracy and more robustness than any other method presented previously.

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퍼지추론규칙과 PNN 구조를 융합한 FPNN 알고리즘 (The FPNN Algorithm combined with fuzzy inference rules and PNN structure)

  • 박호성;박병준;안태천;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 G
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    • pp.2856-2858
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    • 1999
  • In this paper, the FPNN(Fuzzy Polynomial Neural Networks) algorithm with multi-layer fuzzy inference structure is proposed for the model identification of a complex nonlinear system. The FPNN structure is generated from the mutual combination of PNN (Polynomial Neural Network) structure and fuzzy inference method. The PNN extended from the GMDH(Group Method of Data Handling) uses several types of polynomials such as linear, quadratic and modifled quadratic besides the biquadratic polynomial used in the GMDH. In the fuzzy inference method, simplified and regression polynomial inference method which is based on the consequence of fuzzy rule expressed with a polynomial such as linear, quadratic and modified quadratic equation are used Each node of the FPNN is defined as a fuzzy rule and its structure is a kind of fuzzy-neural networks. Gas furnace data used to evaluate the performance of our proposed model.

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유리분수함수 근사법에 기반한 풍하중을 받는 구조물의 동특성 추정 (Modal Parameter Estimations of Wind-Excited Structures based on a Rational Polynomial Approximation Method)

  • 김상범;이완수;윤정방
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.287-292
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    • 2005
  • This paper presents a rational polynomial approximation method to estimate modal parameters of wind excited structures using incomplete noisy measurements of structural responses and partial measurements of wind velocities only. A stochastic model of the excitation wind force acting on the structure is estimated from partial measurements of wind velocities. Then the transfer functions of the structure are approximated as rational polynomial functions. From the poles and zeros of the estimated rational polynomial functions, the modal parameters, such as natural frequencies, damping ratios, and mode shapes are extracted. Since the frequency characteristics of wind forces acting on structures can be assumed as a smooth Gaussian process especially around the natural frequencies of the structures according to the central limit theorem (Brillinger, 1969; Yaglom, 1987), the estimated modal parameters are robust and reliable with respect to the assumed stochastic input models. To verify the proposed method, the modal parameters of a TV transmission tower excited by gust wind are estimated. Comparison study with the results of other researchers shows the efficacy of the suggested method.

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ON THE DISTANCE TO A ROOT OF COMPLEX POLYNOMIALS UNDER NEWTON'S METHOD

  • Chaiya, Malinee;Chaiya, Somjate
    • 대한수학회지
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    • 제57권5호
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    • pp.1119-1133
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    • 2020
  • In this paper, we derive an upper bound for the distance from a point in the immediate basin of a root of a complex polynomial to the root itself. We establish that if z is a point in the immediate basin of a root α of a polynomial p of degree d ≥ 12, then ${\mid}z-{\alpha}{\mid}{\leq}{\frac{3}{\sqrt{d}}\(6{\sqrt{310}}/35\)^d{\mid}N_p(z)-z{\mid}$, where Np is the Newton map induced by p. This bound leads to a new bound of the expected total number of iterations of Newton's method required to reach all roots of every polynomial p within a given precision, where p is normalized so that its roots are in the unit disk.

순차적 다항식 근사화를 적용한 효율적 선탐색기법의 개발 (Development of an Efficient Line Search Method by Using the Sequential Polynomial Approximation)

  • 김민수;최동훈
    • 대한기계학회논문집
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    • 제19권2호
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    • pp.433-442
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    • 1995
  • For the line search of a multi-variable optimization, an efficient algorithm is presented. The algorithm sequentially employs several polynomial approximations such as 2-point quadratic interpolation, 3-point cubic interpolation/extrapolation and 4-point cubic interpolation/extrapolation. The order of polynomial function is automatically increased for improving the accuracy of approximation. The method of approximation (interpolation or extrapolation) is automatically switched by checking the slope information of the sample points. Also, for selecting the initial step length along the descent vector, a new approach is presented. The performance of the proposed method is examined by solving typical test problems such as mathematical problems, mechanical design problems and dynamic response problems.

Homogeneous and Non-homogeneous Polynomial Based Eigenspaces to Extract the Features on Facial Images

  • Muntasa, Arif
    • Journal of Information Processing Systems
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    • 제12권4호
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    • pp.591-611
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    • 2016
  • High dimensional space is the biggest problem when classification process is carried out, because it takes longer time for computation, so that the costs involved are also expensive. In this research, the facial space generated from homogeneous and non-homogeneous polynomial was proposed to extract the facial image features. The homogeneous and non-homogeneous polynomial-based eigenspaces are the second opinion of the feature extraction of an appearance method to solve non-linear features. The kernel trick has been used to complete the matrix computation on the homogeneous and non-homogeneous polynomial. The weight and projection of the new feature space of the proposed method have been evaluated by using the three face image databases, i.e., the YALE, the ORL, and the UoB. The experimental results have produced the highest recognition rate 94.44%, 97.5%, and 94% for the YALE, ORL, and UoB, respectively. The results explain that the proposed method has produced the higher recognition than the other methods, such as the Eigenface, Fisherface, Laplacianfaces, and O-Laplacianfaces.

PATCHWISE REPRODUCING POLYNOMIAL PARTICLE METHOD FOR THICK PLATES: BENDING, FREE VIBRATION, AND BUCKLING

  • Kim, Hyunju;Jang, Bongsoo
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제17권2호
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    • pp.67-85
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    • 2013
  • Reproducing Polynomial Particle Method (RPPM) is one of meshless methods that use meshes minimally or do not use meshes at all. In this paper, the RPPM is employed for free vibration analysis of shear-deformable plates of the first order shear deformation model (FSDT), called Reissner-Mindlin plate. For numerical implementation, we use flat-top partition of unity functions, introduced by Oh et al, and patchwise RPPM in which approximation functions have high order polynomial reproducing property and the Kronecker delta property. Also, we demonstrate that our method is highly effective than other existing results for various aspect ratios and boundary conditions.