• 제목/요약/키워드: on-line identification

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비선형계통 고장진단을 위한 온-라인 퍼지동적모델 식별 (Identification of Fuzzy Dynamic Model for Fault Diagnosis of Nonlinear System)

  • 이종렬;배상욱;이기상;박귀태
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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    • pp.204-210
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    • 1998
  • This paper discusses an on-line fuzzy dynamic model(FDM) identification of nonlinear processes for the design of fuzzy model based fault detection and isolation(FDI). The dynamic behavior of a nonlinear process is represented by a fuzzy aggregation of a set of local linear models. The identification is divided into two procedures. The first is the off-line identification of membership function. The second is the on-line identification of the local linear models. Then, we propose a residual generation scheme based on the parameters of local linear models and show that the scheme can be used for the design of FDI

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On-Line Aircraft Parameter Identification Using Fourier Transform Regression With an Application to NASA F/A-18 Harv Flight Data

  • Song, Yongkyu;Song, Byungheum;Seanor, Brad;Napolitano, Marcello R.
    • Journal of Mechanical Science and Technology
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    • 제16권3호
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    • pp.327-337
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    • 2002
  • This paper applies a recently developed on-line parameter identification (PID) technique to sets of real flight data and compares the results with those of a state-of-the-art off-line PID technique. The on-line PID technique takes Linear Regression from Fourier Transformed equations and the off-line PID is based on the traditional Maximum Likelihood method. Sets of flight data from the NASA F/A-18 High Alpha research Vehicle (HARV) circraft, which has been recorded from specifically designed maneuvers and used for our line parameter estimation, are used for this study. The emphasis is given on the accuracy and on-line measure of reliability of the estimates. The comparison is performed for both longitudinal and lateral-directional dynamics for maneuvers at angles of attack ranging u=20°through $\alpha$=40°. Results of the two estimation processes are also compared with baseline wind tunnel estimates whenever possible.

3상 불평형 정전류 부하 조건에서의 동 위상 판별에 대한 분석 및 한계에 관한 연구 (A Study on the Analysis and Limitations of the Same Phase Identification Under 3-Phase Unbalanced Constant Current Loads)

  • 변희정;손수국
    • 조명전기설비학회논문지
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    • 제26권6호
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    • pp.38-46
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    • 2012
  • In this paper, the necessity for the identification of the absolute phase value is introduced and analyzed for a particular conductor line of a 3-phase type distribution network and the recent methods are also introduced. For the determination of the exact phase value for a specific point in the line, as compared with the phase reference point, the measured phase value must be within a range of ${\pm}60[^{\circ}]$. However, the phase of a particular point can fluctuate depending on the line constant, transformer wiring method, line length, line amperage, etc. A theoretical formulation such as Simulink modeling and analysis for a distribution network are conducted for the identification of phase at a specific point in the line. In particular, through evaluating the effects of unbalanced current loads at the time of determination of the phase value, the limitations of the present method for the determination of phases is described.

Threshold Setting for LOS/NLOS Identification Based on Joint TOA and RSS

  • Guan, XuFeng;Hur, SooJung;Park, Yongwan
    • 대한임베디드공학회논문지
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    • 제5권3호
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    • pp.152-156
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    • 2010
  • Non-line-of-sight (NLOS) propagation is one of the challenges in radio positioning. Distinguishing the transmission status of the communication as line-of-sight (LOS) or NLOS is of great importance for the wireless communication systems. This paper focuses on the identification of NLOS based on time-of-arrival (TOA) distance estimates and the received signal strength (RSS) measurements. We set a path loss threshold based on the joint TOA and RSS based NLOS detection method to determine LOS or NLOS. Simulation results show that the proposed method ensures the correct of detection for the LOS condition and can improve the NLOS identification for the weak noise and long distance.

Laguerre 모델을 이용한 미지 시스템의 온-라인 시스템 동정에 관한 연구 (A Study the On-Line Systems Identification of Unknown Systems using Laguerre Models)

  • 오현철;김윤상;이재춘;안두수
    • 대한전기학회논문지:전력기술부문A
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    • 제48권6호
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    • pp.728-734
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    • 1999
  • An on-line system identification scheme of unknown system is proposed based on a Laguerre models representation. The unknown parameters are detemined using recursive least-square identification. The proposed method have the advantage that an unknown system can be modelled without structural knowledge and assumption about the true model order and time delay. Therefore, the proposed method can make the design procedure very when compared to widely-used conventional method.

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Target identification for visual tracking

  • Lee, Joon-Woong;Yun, Joo-Seop;Kweon, In-So
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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    • pp.145-148
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    • 1996
  • In moving object tracking based on the visual sensory feedback, a prerequisite is to determine which feature or which object is to be tracked and then the feature or the object identification precedes the tracking. In this paper, we focus on the object identification not image feature identification. The target identification is realized by finding out corresponding line segments to the hypothesized model segments of the target. The key idea is the combination of the Mahalanobis distance with the geometrica relationship between model segments and extracted line segments. We demonstrate the robustness and feasibility of the proposed target identification algorithm by a moving vehicle identification and tracking in the video traffic surveillance system over images of a road scene.

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On-line Identification of a Fuzzy System

  • Kim, euntai;Lee, Heejin;Park, Minkee;Park, Mignon
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.685-690
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    • 1998
  • This paper presents an explanation regarding on-line identification of a fuzzy system. The fuzzy system to be identified is assumed to be in the type of singletion consequent parts and be represented by a linear combination of fuzzy basis function (FBF's). For on-line identification, squared-cosine (SCOS) fuzzy basis function is introduced to reduce the number of parameters to be identified and make the system consistent and differentiable. Then the parameters of the fuzzy system are identified on-line by the gradient search method. Finally, a computer simulation is performed to illustrate the validity of the suggested algorithms.

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유한요소법과 프라이자흐 모델을 이용한 동기형 릴럭턴스 전동기( Synchronous Reluctance Motor : SynRM)의 On-line 판정시스템 특성 해석 (The On-line Identification System Characteristics Analysis of Synchronous Reluctance Motor Using a Coupled FEM & Preisach Model)

  • 김홍석;이명기;이민명;이중호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1001-1002
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    • 2007
  • This study investigates the dynamic characteristics of Synchronous Reluctance Motor (SynRM), with segmental rotor structure, using finite element method in which the moving mesh technique is considered. The focus of this paper is the efficiency of on-line parameter identification system for position sensorless control of a SynRM under saturation and iron loss. Comparisons are given with angle of the observer and those of proposed FEM & Preisach model of synchronous reluctance motor, respectively. The position sensorless control using identified motor parameters is realized, and the effective of the on-line parameter identification system is verified by experimental results.

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불안정한 공정에 대한 온라인 공정 확인 및 자동 조절 (On-line process identification and autotuning for unstable processes)

  • 곽희진;성수환;이인범
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.832-835
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    • 1997
  • In this paper, we first analyze the structural limitation of the conventional PID controller in controlling unstable processes through mathematical proof. To overcome this structural limitation, we add an internal feedback loop to the PID controller. Secondly, we obtain conditions when unstable processes can be stabilized by a controller through an analytical analysis. Finally, we propose a simple on-line process identification and autotuning method for unstable processes. Many simulation results show that, in spite of its simplicity, the proposed on-line process identification method provides good accuracy in modeling the unstable process and acceptable robustness to measurement noises and disturbances. Also, the proposed autotuner shows good control performances for both servo and regulatory problems.

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미지의 선형 MIMO 시스템에 대한 On-Line 모델링 알고리즘 (On-Line Identification Algorithm for Unknown Linear MIMO Systems)

  • 최수일;김병국
    • 전자공학회논문지B
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    • 제31B권7호
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    • pp.58-65
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    • 1994
  • A recursive on-line algorithm for orthogonal ARMA identification is proposed for linear MIMO systems with unknown parameters time delay and order. This algorithm is based on the Gram-Schmidt orthogonalization of basis functions, and extended to a recursiveform by using new functions of two dimensional autocorrelations and crosscorrelations of inputs and outputs. This proposed algorithm can also cope with slowly time-varying or order-varying systems. Various simulations reveal the performance of the algorithm.

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