• 제목/요약/키워드: parametric method

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파라메트릭 선형계획문제의 해법: 선형제약 경우 (A Method for Solving Parametric Nonlinear Programming Problems with Linear Constraints)

  • 양용준
    • 한국경영과학회지
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    • 제7권1호
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    • pp.11-16
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    • 1982
  • A method is described for the solution of a linearly constrained program with parametric nonlinear objective function. The algorithm proposed in this paper may be regarded as an extension of the simplex method for parametric linear programming. Namely, it specifies the basis at each stage such that feasibility ana optimality of the original problem are satisfied by the optimal solution of the reduced parametric problem involving only nonbasic variables. It is shown that under appropriate assumptions the algorithm is finite. Parametric procedures are also indicated for solving each reduced parametric problem by maintaining the Kuhn-Tucker conditions as the parameter value varies.

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Single Image Depth Estimation With Integration of Parametric Learning and Non-Parametric Sampling

  • Jung, Hyungjoo;Sohn, Kwanghoon
    • 한국멀티미디어학회논문지
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    • 제19권9호
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    • pp.1659-1668
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    • 2016
  • Understanding 3D structure of scenes is of a great interest in various vision-related tasks. In this paper, we present a unified approach for estimating depth from a single monocular image. The key idea of our approach is to take advantages both of parametric learning and non-parametric sampling method. Using a parametric convolutional network, our approach learns the relation of various monocular cues, which make a coarse global prediction. We also leverage the local prediction to refine the global prediction. It is practically estimated in a non-parametric framework. The integration of local and global predictions is accomplished by concatenating the feature maps of the global prediction with those from local ones. Experimental results demonstrate that the proposed method outperforms state-of-the-art methods both qualitatively and quantitatively.

CIRCLE APPROXIMATION USING PARAMETRIC POLYNOMIAL CURVES OF HIGH DEGREE IN EXPLICIT FORM

  • Ahn, Young Joon
    • 대한수학회논문집
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    • 제37권4호
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    • pp.1259-1267
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    • 2022
  • In this paper we present a full circle approximation method using parametric polynomial curves with algebraic coefficients which are curvature continuous at both endpoints. Our method yields the n-th degree parametric polynomial curves which have a total number of 2n contacts with the full circle at both endpoints and the midpoint. The parametric polynomial approximants have algebraic coefficients involving rational numbers and radicals for degree higher than four. We obtain the exact Hausdorff distances between the circle and the approximation curves.

Bayesian Semi-Parametric Regression for Quantile Residual Lifetime

  • Park, Taeyoung;Bae, Wonho
    • Communications for Statistical Applications and Methods
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    • 제21권4호
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    • pp.285-296
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    • 2014
  • The quantile residual life function has been effectively used to interpret results from the analysis of the proportional hazards model for censored survival data; however, the quantile residual life function is not always estimable with currently available semi-parametric regression methods in the presence of heavy censoring. A parametric regression approach may circumvent the difficulty of heavy censoring, but parametric assumptions on a baseline hazard function can cause a potential bias. This article proposes a Bayesian semi-parametric regression approach for inference on an unknown baseline hazard function while adjusting for available covariates. We consider a model-based approach but the proposed method does not suffer from strong parametric assumptions, enjoying a closed-form specification of the parametric regression approach without sacrificing the flexibility of the semi-parametric regression approach. The proposed method is applied to simulated data and heavily censored survival data to estimate various quantile residual lifetimes and adjust for important prognostic factors.

파라메트릭 스피커의 근접음장 방향성 특성연구 (Directional Characteristics of Parametric Loudspeakers in Near-field)

  • 주형식;김양한
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.545-550
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    • 2005
  • A parametric loudspeaker is a device to generate highly directional sound using ultrasounds. The parametric loudspeaker could be used to focus sound in a limited space, so it is important to study the characteristics of the parametric loudspeaker in near-field. Mechanism of the audible sound generation in the parametric loudspeaker is explained by nonlinear interaction of the ultrasounds and is modeled as KZK equation, the nonlinear wave equation which contains attenuation, nonlinearity and diffraction. To measure the directional characteristics of the parametric loudspeaker precisely, a method to reduce the spurious signal which taints the measured signal was invented. With the method, directivity patterns of the parametric loudspeaker were measured and compared to the approximated solution and piston sources.

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Spectral analysis of random process

  • Akizuki, Kageo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.13-20
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    • 1994
  • The spectrum estimation methods of random processes are expressed in this paper. Beginning with the basic theory, non-parametric and parametric methods are overviewed. As to non-parametric method, numerical calculation method is also discussed. As to parametric method, AR model is a very famous and effective model representing random process. Estimation methods of AR parameters which have been proposed are mentioned here. Wavelet analysis is a recently interested technique in signal processing. An application of wavelet analysis is also shown.

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꼬리가 두꺼운 분포의 고분위수에 대한 준모수적 붓스트랩 신뢰구간 (Semi-parametric Bootstrap Confidence Intervals for High-Quantiles of Heavy-Tailed Distributions)

  • 김지현
    • Communications for Statistical Applications and Methods
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    • 제18권6호
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    • pp.717-732
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    • 2011
  • 꼬리가 두꺼운 분포의 고분위수에 대한 신뢰구간을 구할 때 적절한 붓스트랩 방법은 무엇인가에 대해 알아보았다. 비모수적 방법과 모수적 방법, 그리고 준모수적 방법의 성능을 모의실험을 통해 비교하였다.

CDM과 리파토프 정리를 이용한 구간 플랜트의 목적다항식 설계 (Target Polynomial Design for Interval Plant Using Lipatov Theorem and CDM)

  • 오학준;정태진;이진규;정찬수
    • 대한전기학회논문지:시스템및제어부문D
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    • 제50권1호
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    • pp.1-7
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    • 2001
  • For a parametric uncertain system, there are many results on stability analysis, but only a few synthesis methods. In this paper, we proposed a new target polynomial decision method for the parametric uncertain system to stabilize the closed loop system with maximal parametric $l_2$ stability margin. To this, we used both Lipatov Theorem and coefficient diagram method(CDM). To show the effectiveness of the proposed method, we designed a robust controller for the inverted pendulum system with parametric uncertainties using fixed order pole assignment(FOPA) method and its performance was compared with that of the ${\mu}$ synthesis methods.

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자유 곡면의 CNC 가공을 위한 가공경로의 생성 (A Toolpath Generation for CNC Machining of Free-form Surfaces)

  • 성완;최종호;송오석
    • 한국정밀공학회지
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    • 제16권4호통권97호
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    • pp.129-137
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    • 1999
  • A parametric curve interpolator has been proposed for machining curves instead of a linear interpolator in which curves are approximated by a set of line segment. The parametric curve interpolator is superior to linear interpolator in machining time and contour error and generate exact position commands directly from curve equations. In this paper, a new toolpath generation method is proposed based on the parametric curve interpolator. This method retains all the benefits of parametric curve interpolator and can bound the scallop height within a specified value. By interpolating curves and surfaces directly from the mathematical equations, the amount of data from CAD/CAM system to CNC controller can be significantly reduced. The proposed method was implemented on a CNC controller and was confirmed to give a better result than the other existing method.

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Multi-level approach for parametric roll analysis

  • Kim, Tae-Young;Kim, Yong-Hwan
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제3권1호
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    • pp.53-64
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    • 2011
  • The present study considers multi-level approach for the analysis of parametric roll phenomena. Three kinds of computation method, GM variation, impulse response function (IRF), and Rankine panel method, are applied for the multi-level approach. IRF and Rankine panel method are based on the weakly nonlinear formulation which includes nonlinear Froude-Krylov and restoring forces. In the computation result of parametric roll occurrence test in regular waves, IRF and Rankine panel method show similar tendency. Although the GM variation approach predicts the occurrence of parametric roll at twice roll natural frequency, its frequency criteria shows a little difference. Nonlinear roll motion in bichromatic wave is also considered in this study. To prove the unstable roll motion in bichromatic waves, theoretical and numerical approaches are applied. The occurrence of parametric roll is theoretically examined by introducing the quasi-periodic Mathieu equation. Instability criteria are well predicted from stability analysis in theoretical approach. From the Fourier analysis, it has been verified that difference-frequency effects create the unstable roll motion. The occurrence of unstable roll motion in bichromatic wave is also observed in the experiment.