• 제목/요약/키워드: Nonlinear Term

검색결과 552건 처리시간 0.029초

성토지반에 타입된 H 말뚝의 약축방향에 대한 횡방향 장기지지거동 (Lateral long term behavior for web direction of Driven H-Piles in Embankment)

  • 박영호;정경자;김낙영;황영철
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 기초기술학술발표회
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    • pp.43-56
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    • 2002
  • To find a lateral long term behavior of driven H-piles in embankment, inclinometer is installed at pile and measurement is done during a year. When behavior of measured slope angles is in accord with behavior of nonlinear p-y curves(Reese, Murchison and O'Neil, Matlock's p-y analysis), maximum displacement of pile head, maximum stress and maximum bending moment of pile obtained from the numerical analysis are shown. As results, maximum lateral displacement at pile head, maximum stress and maximum bending moment of pile are shown linear behavior, And maximum lateral load, maximum lateral displacement, and maximum bending moment at pile obtained from the numerical analysis are 8∼12.4tonf, 9∼10.1㎜, and 10.39∼12.67tonf-m per pile according to the curves, respectively.

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On Long-term Prediction Scheme in Ocean Engineering

  • Kwon, Sun-Hong;Kim, Dea-Woong
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • 제3권1호
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    • pp.29-34
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    • 2000
  • This paper proposes a long-term prediction of offshore structures in ocean waves. All short-term statistics is generated by the simulation for all the combinations of significant wave heights and spectral peak periods. The simulation has been tested first on linear system, whose analytic solution is known, to verify if the simulation works accurately. Then the scheme was applied to the nonlinear system. This paper demonstrated that the proposed scheme could be an efficient tool in estimating the response of offshore structures.

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THE CONSISTENCY OF NONLINEAR REGRESSION MINIMIZING $L_p$-NORM

  • Choi, Seung-Hoe;Park, Kyung-Ok
    • East Asian mathematical journal
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    • 제14권2호
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    • pp.421-427
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    • 1998
  • In this paper we provide sufficient conditions which ensure the strong consistency of $L_p$-norm estimation in nonlinear regression model when the probability distribution of the errors term is symmetric about zero. The least absolute deviation and least square estimation are discussed as special cases of the proposed estimation.

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현가장치의 비선형 설계변수 추정 (Nonlinear Parameter Estimation of Suspension System)

  • 박주표;최연선
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.281-286
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    • 2003
  • A Suspension system of a car is composed of dampers and springs. The dampers and springs usually have nonlinear characteristics. However, the nonlinear characteristics of the springs and dampers through analytical model cannot agree with the experimental results. Therefore, the nonlinearity of the suing and damper should be known from the experimental results. In this study, the methods of system identification for nonlinear dynamic system in time domain are discussed and the nonlinear parameter estimation lot experimental data of an EF-SONATA car was done. The results show that a cubic and a coupled term should be considered to model the suspension system.

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Simultaneous resonances of SSMFG cylindrical shells resting on viscoelastic foundations

  • Foroutan, Kamran;Ahmadi, Habib
    • Steel and Composite Structures
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    • 제37권1호
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    • pp.51-73
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    • 2020
  • The present paper investigates the simultaneous resonance behavior of spiral stiffened multilayer functionally graded (SSMFG) cylindrical shells with internal and external functionally graded stiffeners under the two-term large amplitude excitations. The structure is embedded within a generalized nonlinear viscoelastic foundation which is composed of a two-parameter Winkler-Pasternak foundation augmented by a Kelvin-Voigt viscoelastic model with a nonlinear cubic stiffness. The cylindrical shell has three layers consist of ceramic, FGM, and metal. The exterior layer of the cylindrical shell is rich ceramic while the interior layer is rich metal and the functionally graded material layer is located between these layers. With regard to classical shells theory, von-Kármán equation, and Hook law, the relations of stress-strain are derived for shell and stiffeners. The spiral stiffeners of the cylindrical shell are modeled according to the smeared stiffener technique. According to the Galerkin method, the discretized motion equation is obtained. The simultaneous resonance is obtained using the multiple scales method. Finally, the influences of different material and geometrical parameters on the system resonances are investigated comprehensively.

Nonlinear modelling and analysis of thin piezoelectric plates: Buckling and post-buckling behaviour

  • Krommer, Michael;Vetyukova, Yury;Staudigl, Elisabeth
    • Smart Structures and Systems
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    • 제18권1호
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    • pp.155-181
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    • 2016
  • In the present paper we discuss the stability and the post-buckling behaviour of thin piezoelastic plates. The first part of the paper is concerned with the modelling of such plates. We discuss the constitutive modelling, starting with the three-dimensional constitutive relations within Voigt's linearized theory of piezoelasticity. Assuming a plane state of stress and a linear distribution of the strains with respect to the thickness of the thin plate, two-dimensional constitutive relations are obtained. The specific form of the linear thickness distribution of the strain is first derived within a fully geometrically nonlinear formulation, for which a Finite Element implementation is introduced. Then, a simplified theory based on the von Karman and Tsien kinematic assumption and the Berger approximation is introduced for simply supported plates with polygonal planform. The governing equations of this theory are solved using a Galerkin procedure and cast into a non-dimensional formulation. In the second part of the paper we discuss the stability and the post-buckling behaviour for single term and multi term solutions of the non-dimensional equations. Finally, numerical results are presented using the Finite Element implementation for the fully geometrically nonlinear theory. The results from the simplified von Karman and Tsien theory are then verified by a comparison with the numerical solutions.

케이블의 동적거동에 미치는 비선형 영향 (Nonlinear Effects on the Cable Dynamic Behaviour)

  • 신현경
    • 대한조선학회지
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    • 제27권1호
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    • pp.11-16
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    • 1990
  • 거친 해상에서 케이블이 형성된 수 있는 큰 동장력(large dynamic tensile forces)과 기하학적 비선형성(geometric nonlinearity)의 고려는 비선형 케이블 운동방정식(nonlinear cable dynamics)의 해에 상당한 영향을 끼치며 이 결과의 응용은 케이블의 극단장력(extreme tensions)과 slack-and-snapping 케이블의 연구에서 필수적인 부분이 될 것이다. 비선형 유체항력만을 포함한 경우와 기하학적 비선형성과 큰 동장력항을 함께 포함하는 경우의 케이블 운동방정식의 해를 비교하여, 케이블의 동적 거동에 대한 기하학적 비선형과 큰 동장력항의 복합적인 영향을 연구한다. 큰 동장력항과 기하학적 비선형성의 고려는, 최대 동장력의 증가를 가져오나 반면에 최소 동장력의 크기에서의 감소를 가져옴으로, 결국 동장력의 평균값의 상승과 그로인한 케이블의 피로수명 단축을 유발할 수 있다.

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AN EXTRAPOLATED HIGHER ORDER CHARACTERISTIC FINITE ELEMENT METHOD FOR NONLINEAR SOBOLEV EQUATIONS

  • Ohm, Mi Ray;Shin, Jun Yong
    • East Asian mathematical journal
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    • 제34권5호
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    • pp.601-614
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    • 2018
  • In this paper, we introduce an extrapolated higher order characteristic finite element method to approximate solutions of nonlinear Sobolev equations with a convection term and we establish the higher order of convergence in the temporal and the spatial directions with respect to $L^2$ norm.