• 제목/요약/키워드: nonlinear system modeling

검색결과 715건 처리시간 0.025초

3차원 로봇 레이저 스캐닝 시스템의 모델링과 캘리브레이션 (Modeling and Calibration of a 3D Robot Laser Scanning System)

  • 이종광;윤지섭;강이석
    • 제어로봇시스템학회논문지
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    • 제11권1호
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    • pp.34-40
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    • 2005
  • In this paper, we describe the modeling for the 3D robot laser scanning system consisting of a laser stripe projector, camera, and 5-DOF robot and propose its calibration method. Nonlinear radial distortion in the camera model is considered for improving the calibration accuracy. The 3D range data is calculated using the optical triangulation principle which uses the geometrical relationship between the camera and the laser stripe plane. For optimal estimation of the system model parameters, real-coded genetic algorithm is applied in the calibration process. Experimental results show that the constructed system is able to measure the 3D position within about 1mm error. The proposed scheme could be applied to the kinematically dissimilar robot system without losing the generality and has a potential for recognition for the unknown environment.

편적 선형 진동계의 실험과 해석 (Experiment and Analysis of Piecewise-Linear Vibration systems)

  • 최연선
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.461-467
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    • 2000
  • Mechanical problems are basically three dimensional nonlinear dynamic problems, which makes it difficult to solve. The difficulties are tried to overcome by modeling, i.e., simplifications of the system with the assumptions or negligence of minute effects. However, the correctness or usefulness of the model should be verified through the comparison with experimental results, which is the process of physical understanding of the system. The understanding of physics of the system make it possible to design or operation of the system. The effects of clearance and friction are always difficult problems in mechanical system due to its nonlinearity. The nonlinearity comes from piecewise-linear characteristics of the stiffness and damping of the system. The modeling of piecewise-linearity and the experimental result are discussed in this paper for impact and friction oscillator and rotor rubbing problem, which is the combination of impact and friction problems.

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의사 결정 구조에 의한 오존 농도예측 (Forecasting Ozone Concentration with Decision Support System)

  • 김재용;김태헌;김성신;이종범;김신도;김용국
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.368-368
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    • 2000
  • In this paper, we present forecasting ozone concentration with decision support system. Since the mechanism of ozone concentration is highly complex, nonlinear, and nonstationary, modeling of ozone prediction system has many problems and results of prediction are not good performance so far. Forecasting ozone concentration with decision support system is acquired to information from human knowledge and experiment data. Fuzzy clustering method uses the acquisition and dynamic polynomial neural network gives us a good performance for ozone prediction with ability of superior data approximation and self-organization.

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고속전철 집전시스템의 동역학 해석에 관한 연구(I. 가선계의 모델링 및 해석) (Dynamic Analysis of a Pantograph-Catenary System for High-Speed Train(I. Modeling and Analysis of a Catenary System))

  • 서종휘;정일호;박태원;목진용;김영국;김석원
    • 한국정밀공학회지
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    • 제22권1호
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    • pp.152-159
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    • 2005
  • The dynamic properties between catenary and pantograph of high-speed train are very important factors to affect the stable electric power supply. So as to design the reliable current collection system, a multibody simulation model is needed. In this paper, the dynamic analysis method for a pantograph-catenary cable system of high-speed train is presented. The very deformable motion of a catenary cable is demonstrated using nonlinear continuous beam theory, which is based on an absolute nodal coordinate formulation, and the pantograph is modeled as a rigid multibody. The proposed method might be very efficient, because this method can present the nonlinear properties of a flexible catenary cable and set a various boundary conditions.

암 치료를 위한 면역반응의 체계적인 연구 (A Systems Approach to Immune Response for Cancer Treatment)

  • 이권순
    • 대한의용생체공학회:의공학회지
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    • 제13권3호
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    • pp.181-188
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    • 1992
  • This paper provides an overview of system analysis of immunology. The theoretical research in this area is aimed at an understanding of the precise manner by which the immune system controls Infec pious diseases, cancer, and AIDS. This can provide a systematic plan for immunological experimentation by means of an integrated program of immune system analysis, mathematical modeling and computer simulation. Biochemical reactions and cellular fission are naturally modeled as nonlinear dynamical processes to synthesize the human immune system! as well as the complete organism it is intended to protect. A foundation for the control of tumors is presented, based upon the formulation of a realistic, knowledge based mathematical model of the interaction between tumor cells and the immune system. Ordinary bilinear differential equations which are coupled by such nonlinear term as saturation are derived from the basic physical phenomena of cellular and molecular conservation. The parametric control variables relevant to the latest experimental data are also considered. The model consists of 12 states, each composed of first-order, nonlinear differential equations based on cellular kinetics and each of which can be modeled bilinearly. Finally, tumor control as an application of immunotherapy is analyzed from the basis established.

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뉴트럴 타입 시간 지연을 갖는 네트워크 기반 시스템의 샘플치 퍼지 제어기 설계 (Sampled-data Fuzzy Controller for Network-based Systems with Neutral Type Delays)

  • 주영훈
    • 한국지능시스템학회논문지
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    • 제18권2호
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    • pp.151-156
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    • 2008
  • 본 논문은 뉴트럴 타입 시간 지연을 가지는 네트워크 기반 시스템의 안정도 분석 및 샘플치 퍼지 제어기 설계 방법에 관하여 논의한다. 먼저 대상이 되는 비선형 네트워크 시스템을 T-S (Takagi-Sugeno) 퍼지 모델로 표현한다. 제안하는 샘플치 퍼지 제어기를 모델링하는 퍼지 규칙과 같은 멤버쉽 함수를 가지게 설계한다. Lyapunov-Krasovskii의 안정화 이론을 도입하여 이를 바탕으로 뉴트럴 형태의 시간 지연을 갖는 T-S 퍼지 시스템의 안정도를 판별한다. T-S 퍼지 시스템의 안정도 조건을 제시하고 선형 행렬 부등식의 형태로 표현한다. 제안된 선형 행렬 부등식의 해를 통하여 샘플치 퍼지 제어기의 이득 값을 설계한다. 마지막으로, 본 논문에서 제안한 방법의 적용 가능성과 일반성을 평가하기 위하여 수치적인 예를 적용한다.

Dynamic stability and structural improvement of vibrating electrically curved composite screen subjected to spherical impactor: Finite element and analytical methods

  • Xiao, Caiyuan;Zhang, Guiju
    • Steel and Composite Structures
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    • 제43권5호
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    • pp.533-552
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    • 2022
  • The current article deals with the dynamic stability, and structural improvement of vibrating electrically curved screen on the viscoelastic substrate. By considering optimum value for radius curvature of the electrically curved screen, the structure improvement of the system occurs. For modeling the electrically system, the Maxwell's' equation is developed. Hertz contact model in employed to obtain contact forces between impactor and structure. Moreover, variational methods and nonlinear von Kármán model are used to derive boundary conditions (BCs) and nonlinear governing equations of the vibrating electrically curved screen. Galerkin and Multiple scales solution approach are coupled to solve the nonlinear set of governing equations of the vibrating electrically curved screen. Along with the analytical solution, 3D finite element simulation via ABAQUS package is provided with the aid of a FE package for simulating the current system's response. The results are categorized in 3 different sections. First, effects of geometrical and material parameters on the vibrational performance and stability of the curves panel. Second, physical properties of the impactor are taken in to account and their effect on the absorbed energy and velocity profile of the impactor are presented. Finally, effect of the radius and initial velocity on the mode shapes of the current structure is demonstrated.

Structure Identification of a Neuro-Fuzzy Model Can Reduce Inconsistency of Its Rulebase

  • Wang, Bo-Hyeun;Cho, Hyun-Joon
    • 한국지능시스템학회논문지
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    • 제17권2호
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    • pp.276-283
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    • 2007
  • It has been shown that the structure identification of a neuro-fuzzy model improves their accuracy performances in a various modeling problems. In this paper, we claim that the structure identification of a neuro-fuzzy model can also reduce the degree of inconsistency of its fuzzy rulebase. Thus, the resulting neuro-fuzzy model serves as more like a structured knowledge representation scheme. For this, we briefly review a structure identification method of a neuro-fuzzy model and propose a systematic method to measure inconsistency of a fuzzy rulebase. The proposed method is applied to problems or fuzzy system reproduction and nonlinear system modeling in order to validate our claim.

A simple and rapid approach to modeling chromium breakthrough in fixed bed adsorber

  • Chu, Khim Hoong
    • Advances in environmental research
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    • 제7권1호
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    • pp.29-37
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    • 2018
  • A simple mathematical model for predicting fixed bed adsorption dynamics is described. The model is characterized by a linear adsorption isotherm and a linear driving force expression for mass transfer. Its analytic solution can be approximated with an algebraic equation in closed form which is easily evaluated by spreadsheet computation. To demonstrate one application of the fixed bed model, a previously published adsorption system is used as a case study in this work. The adsorption system examined here describes chromium breakthrough in a fixed bed adsorber packed with imidazole functionalized adsorbent particles and is characterized by a nonlinear adsorption isotherm. However, the equilibrium behavior of the fixed bed adsorber is in essence governed by a linear adsorption isotherm due to the use of a low influent chromium concentration. It is shown that chromium breakthrough is predicted reasonably well by the fixed bed model. The model's parameters can be easily extracted from independent batch experiments. The proposed modeling approach is very simple and rapid, and only Excel is used for computation.

ELM을 이용한 주거용 부하의 부하모델링 기법 개발 (Development of ELM based Load Modeling Method for Residential Loads)

  • 정영택;지평식
    • 전기학회논문지P
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    • 제61권1호
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    • pp.29-34
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    • 2012
  • Due to the increasing of nonlinear loads such as converters and inverters connected to the electric power distribution system, and extensive application of harmonic generation sources with power electronic devices, disturbance of the electric power system and its influences on industries have been continuously increasing. Thus, it is difficult to construct accurate load model for active and reactive power in environments with harmonics. In this research, we develop a load modeling method based on Extreme Learning Machine(ELM) with fast learning procedure for residential loads. Using data sets acquired from various residential loads, the proposed method has been intensively tested. As the experimental results, we confirm that the proposed method makes it possible to effective estimate active and reactive powers than conventional methods.