• 제목/요약/키워드: nonlinear global analysis

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ERROR BOUNDS FOR NONLINEAR MIXED VARIATIONAL-HEMIVARIATIONAL INEQUALITY PROBLEMS

  • A. A. H. Ahmadini;Salahuddin;J. K. Kim
    • Nonlinear Functional Analysis and Applications
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    • 제29권1호
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    • pp.15-33
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    • 2024
  • In this article, we considered a class of nonlinear variational hemivariational inequality problems and investigated a gap function and regularized gap function for the problems. We discussed the global error bounds for such inequalities in terms of gap function and regularized gap functions by utilizing the Clarke generalized gradient, relaxed monotonicity, and relaxed Lipschitz continuous mappings. Finally, as applications, we addressed an application to non-stationary non-smooth semi-permeability problems.

Correlation of Experimental and Analytical Seismic Responses of a 1:5 Scale 3-Story Reinforced Concrete Frame

  • Lee, Han-Seon;Woo, Sung-Woo
    • KCI Concrete Journal
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    • 제12권1호
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    • pp.3-16
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    • 2000
  • A series of dynamic and static tests were conducted to observe the actual responses of a 1:5 scale 3-story reinforced concrete(RC) frame which was designed only for gravity loads. One of the major objectives of these experiments is to provide the calibration to the available static and dynamic inelastic analysis techniques. In this study, the experimental results were simulated by using a nonlinear analysis program for reinforced concrete frame, IDARC-2D. The evaluation of the degree of the simulation leads to the conclusion that while the global behaviors such as story drifts and shears can be in general simulated with the limited accuracy in the dynamic nonlinear analysis, it is rather easy and simple to get the fairly high level of accuracy in the prediction of global and local behaviors in the static nonlinear analysis by using IDARC-2D.

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Optimization Analysis of Trajectory for Re-Entry Vehicle Using Global Orthogonal Polynomial

  • Lee Dae-Woo
    • Journal of Mechanical Science and Technology
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    • 제20권10호
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    • pp.1557-1566
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    • 2006
  • We present a procedure for the application of global orthogonal polynomial into an atmospheric re-entry maneuvering problem. This trajectory optimization is imbedded in a family of canonically parameterized optimal control problem. The optimal control problem is transcribed to nonlinear programming via global orthogonal polynomial and is solved a sparse nonlinear optimization algorithm. We analyze the optimal trajectories with respect to the performance of re-entry maneuver.

비내진 상세를 가진 1:5 축소 철근콘크리트 골조의 비선형 거동에 대한 실험과 해석의 상관성 연구 (A Study of Correlation between Experiment and Analysis of Nonlinear Behaviors of A 1:5 Scale RC Frame with Nonseismic Details)

  • 이한선;우성우;허윤섭
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.483-486
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    • 1999
  • A series of dynamic and static tests were conducted to observe the actual responses of a 1:5 scale 3-story reinforced concrete (RC) frame which was designed only for gravity loads. One of the major objectives of these experiments are to provide the calibration to the available static and dynamic inelastic techniques. In this study, the experimental results were simulated by using a nonlinear analysis program for reinforced concrete frame, IDARC-2D. The evaluation of the degree of the simulation leads to the conclusion that while the global behaviors such as story drifts and shears can be in general simulated with the limited accuracy in the dynamic nonlinear analysis, it is rather easy and simple to get the fairly high level of accuracy in the prediction of global and local behaviors in the static nonlinear analysis by using IDARC-2D.

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크리깅 메타모델의 전역모델과 상관계수 선정 방법 (Selection Method of Global Model and Correlation Coefficients for Kriging Metamodel)

  • 조수길;변현석;이태희
    • 대한기계학회논문집A
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    • 제33권8호
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    • pp.813-818
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    • 2009
  • Design analysis and computer experiments (DACE) model is widely used to express efficiently nonlinear responses in the field of engineering design. As a DACE model, kriging model can approximately replace a simulation model that is very expensive or highly nonlinear. The kriging model is composed of the summation of a global model and a local model representing deviation from the global model. The local model is determined by correlation coefficient with the pre-sampled points, where the accuracy and robustness of the kriging model depends on the selection of proper correlation coefficients. Therefore, to achieve the robust kriging model, the range of the correlation coefficients is explored with respect to the degrees of the global model. Based on this study we propose the proper orders of the global model and range of parameters to make accurate and robust kriging model.

크리깅 메타모델에서 전역 모델에 따른 상관계수의 연구 (A study of the correlation coefficients with respect to the degrees of the global models in the kriging metamodel)

  • 조수길;이태희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.701-705
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    • 2008
  • Design analysis and computer experiments (DACE) model is widely used to express efficiently the nonlinear responses in the field of engineering design. Kriging model, a DACE model, can approximately replace a simulation model that is very expensive or highly nonlinear. The kriging model is composed of the summation of a global model and a local model representing deviation from global model. The local model is determined by correlation coefficient of the pre-sampled points, where determination of the correct correlation coefficient has an effect on accuracy and robustness of the kriging model. Therefore, robustness of the correlation coefficient is explored with respect to degrees of the global model. Then we propose the range of correlation coefficient to make correct and robust kriging model and the influence of the correlation coefficients on the degrees of global model with respect to the nonlinearity of the pre-sampled responses.

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Stability Function을 이용한 공간 뼈대구조물의 기하학적 비선형해석 포뮬레이션 (Geometric Nonlinear Analysis Formulation for Spatial Frames using Stability Functions)

  • 윤영묵;박준우
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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    • pp.201-207
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    • 1998
  • In this study, a geometric nonlinear analysis formulation for spatial frames is developed using the 3D stability functions. For the formulation, the relationships of local and global coordinate systems in force, deformation, and the initial and current configurations of a frame are derived. The force-deformation relationship in global coordinate system is derived as well. The developed formulation is verified in each derivation by reducing the derived equations into 2D equations. The gradual plastification of connections and critical sections can be implemented effectively to this formulation for the complete second order inelastic advanced analysis of spatial frames.

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불확실 비선형 시스템을 위한 강인한 퍼지 모델 기반 제어기 (Design Robust Fuzzy Model-Based Controller for Uncertain Nonlinear Systems)

  • 주영훈;장욱;박진배
    • 대한전기학회논문지:시스템및제어부문D
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    • 제49권8호
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    • pp.407-414
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    • 2000
  • This paper addresses the analysis and design of fuzzy control systems for a class of complex uncertain single-input single-output nonlinear systems. The proposed method represents the nonlinear system using a Takagi-Cugeno fuzzy model and construct a global fuzzy logic controller by blending all local state feedback controllers with a sliding mode controller. Unlike the commonly used parallel distributed compensation technique, we can design a global stable fuzzy controller without finding a common Lyapunov function for all local control systems, and can obtain good tracking performance by using sliding mode control theory. Furthermore, stability analysis is carried out not for the fuzzy model but for the real nonlinear system with uncertainties. Duffing forced oscillation sysmte is used as an example to show the effectiveness and feasibility of the proposed method.

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일종의 일차 비선형 시간 지연 시스템을 위한 안정성 분석 방법 (A Stability Analysis Scheme for a Class of First-Order Nonlinear Time-Delay Systems)

  • 최준영
    • 제어로봇시스템학회논문지
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    • 제14권6호
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    • pp.554-557
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    • 2008
  • We analyze the stability property of a class of nonlinear time-delay systems with time-varying delays. We present a time-delay independent sufficient condition for the global asymptotic stability. In order to prove the sufficient condition, we exploit the inherent property of the considered systems instead of applying the Krasovskii or Razumikhin stability theory that may cause the mathematical difficulty of analysis. We prove the sufficient condition by constructing two sequences that represent the lower and upper bound variations of system state in time, and showing the two sequences converge to an identical point, which is the equilibrium point of the system. The simulation results illustrate the validity of the sufficient condition for the global asymptotic stability.

글로벌 불확실성이 한국의 자본 유출입에 미치는 영향 분석 (The Impacts of Global Uncertainty on the Capital Flows in Korea)

  • 박의환
    • 아태비즈니스연구
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    • 제12권1호
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    • pp.183-193
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    • 2021
  • Purpose - The purpose of this study is to examine the impacts of global uncertainty on gross and net capital flows in Korea. Design/methodology/approach - We conduct an empirical analysis of the impact of global uncertainty on the net and gross capital flows in korea. To investigate the impacts, we incorporate linear and nonlinear ARDL models. Findings - We find global uncertainty has negative impacts on the gross and net capital flows. But this impact is nonlinear. The negative global uncertainty shocks are bigger than the positive global uncertainty shocks on capital flows in Korea. And we find this relationship is noticeable in gross capital inflows. We also find interest rate difference between the US and Korea is the main driving source in capital flow after the Global financial crisis. Research implications or Originality - The results of this study suggest that the negative impacts of global uncertainty are noticeable. This means that economic players in financial markets should be more concerned about the bad news.