• 제목/요약/키워드: S-Parameter

검색결과 5,710건 처리시간 0.035초

다해상도 면 파라미터 추정을 이용한 거리영상 복원 (Range image reconstruction based on multiresolution surface parameter estimation)

  • 장인수;박래홍
    • 전자공학회논문지S
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    • 제34S권6호
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    • pp.58-66
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    • 1997
  • This paper proposes a multiresolution surface parameter estimation method for range images. Based on robust estimation of surface parameters, it approximates a patch to a planar surface in the locally adaptive window. Selection of resolution is made pixelwise by comparing a locally computed homogeneity measure with th eglobal threshold determined by te distribution of the approximation error. The proposed multiresolution surface parameter estimation method is applied to range image reconstruction. Computer simulation results with noisy rnag eimages contaminated by additive gaussian noise and impulse noise show that the proposed multiresolution reconstruction method well preserves step and roof edges compared with the conventional methods. Also the segmentation method based on the estimated surface parameters is shown to be robust to noise.

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분포질량 동흡진기가 부착된 연속체 시스템에 대한 연구 (II) (The Study of Continuous System Combined with Distributed DVA (II))

  • 최정현;임병덕
    • 대한기계학회논문집A
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    • 제28권3호
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    • pp.215-221
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    • 2004
  • Large machine and structure can not be normally treated as lumped parameter system. Such machine or structure must be broken down to individual beams or panels the motion of which must be analysed before an absorber system can be designed for each element. The absorber may be a lumped parameter system or a continuous system. One of the most common elements in a machine or structure is the cantilever, and in this paper is considered the design of a continuous parameter absorber to reduce the transverse vibrations of a beam. So this paper describes the method to obtain the accurate information about combined continuous beam system with DVA. This information is obtained from the combined system's receptance. and this paper shows the convenience and useful informations when design the dynamic vibration absorber with the combined system's receptance.

다물체의 기구해석 및 동적거동해석을 위한 오일러 매개변수의 교정방법 (An Euler Parameter Updating Method for Multibody Kinematics and Dynamics)

  • 김성주;배대성;최창곤;양성모
    • 한국자동차공학회논문집
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    • 제4권4호
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    • pp.9-17
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    • 1996
  • This paper develops a sequential updating method of the Euler parameter generalized coordinates for the machine kinematics and dynamics, The Newton's method is slightly modified so as to utilize the Jacobian matrix with respect to the virtual rotation instead of this with repect to the Euler parameters. An intermediate variable is introduced and the modified Newton's method solves for the variable first. Relational equation of the intermediate variable is then solved for the Euler parameters. The solution process is carried out efficiently by symoblic inversion of the relational equation of the intermediate variable and the iteration equation of the Euler parameter normalization constraint. The proposed method is applied to a kinematic and dynamic analysis with the Generalized Coordinate Partitioning method. Covergence analysis is performed to guarantee the local convergence of the proposed method. To demonstrate the validity and practicalism of the proposed method, kinematic analysis of a motion base system and dynamic analysis of a vehicle are carried out.

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간단하고 정확한 RF MOSFET의 기판효과 모델링과 파라미터 추출방법 (A Simple and Accurate Parameter Extraction Method for Substrate Modeling of RF MOSFET)

  • 심용석;양진모
    • 한국산업정보학회:학술대회논문집
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    • 한국산업정보학회 2002년도 추계공동학술대회
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    • pp.363-370
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    • 2002
  • RF에서 동작하는 초미세 공정 MOS 트랜지스터의 기판 효과에 따른 기판 회로망과 물리적 의미를 가지는 파라미터 추출법이 고려되었다. 제안된 기판 회로망에는 단일의 저항과 링-형태의 기판 콘택에 의해 생성된 인덕터가 포함되었다. 모델 파라미터는 최적화 과정 없이 단절된 게이트와 공통-벌크 구성을 갖는 MOS 트랜지스터에서 측정된 S-파라미터로부터 추출된다. 제안된 기술은 다양한 크기의 MOS 트랜지스터에 적용되어졌다. 추출된 기판 회로망을 이용한 가상실험 결과와 측정치는 약 300Hz까지 일치함을 검증하였다.

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제어기정수에 대한 AMEP와 대규모 전력계통에 미소신호안정도 해석 (Small Small Signal Stability Anslysis by AMEP for Controller Parameter)

  • 심관식;송성근;남해곤;김용구;문채주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 A
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    • pp.112-115
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    • 2001
  • Eigenvalue perturbation theory of augmented system matrix(AMEP) is a useful tool in the analysis and design of large scale power systems. This paper describes the application results of AMEP algorithm with respect to all controller parameter of KEPCO systems. AMEP for interarea and local mode can be used for turning controller parameter, and verifying system data and linear model of controller.

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mGA를 사용한 복잡한 비선형 시스템의 뉴로-퍼지 모델링 (Neuro-Fuzzy Modeling of Complex Nonlinear System Using a mGA)

  • 최종일;이연우;주영훈;박진배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2305-2307
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    • 2000
  • In this paper we propose a Neuro-Fuzzy modeling method using mGA for complex nonlinear system. mGA has more effective and adaptive structure than sGA with respect to using the changeable-length string. This paper suggest a new coding method for applying the model's input and output data to the number of optimul rules of fuzzy models and the structure and parameter identifications of membership function simultaneously. The proposed method realize optimal fuzzy inference system using the learning ability of Neural network. For fine-tune of the identified parameter by mGA, back-propagation algorithm used for optimulize the parameter of fuzzy set. The proposed fuzzy modeling method is applied to a nonlinear system to prove the superiority of the proposed approach through compare with ANFIS.

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유전자 알고리즘을 이용한 제어파라미터 추정모드기반 HFC (Hybrid Fuzzy Controller Based on Control Parameter Estimation Mode Using Genetic Algorithms)

  • 이대근;오성권;장성환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2545-2547
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    • 2000
  • In this paper, a hybrid fuzzy controller using genetic algorithm based on parameter estimation mode to obtain optimal control parameter is presented. First, The control input for the system in the HFC is a convex combination of the FLC's output in transient state and PID's output in steady state by a fuzzy variable, namely, membership function of weighting coefficient. Second, genetic algorithms is presented to automatically improve the performance of hybrid fuzzy controller utilizing the conventional methods for finding PID parameters and estimation mode of scaling factor. The algorithms estimates automatically the optimal values of scaling factors, PID parameters and membership function parameters of fuzzy control rules according to the rate of change and limitation condition of control input. Computer simulations are conducted to evaluate the performance of proposed hybrid fuzzy controller. ITAE, overshoot and rising time are used as a performance index of controller.

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Type 316LN 강의 크리프 수명예측 파라메타의 표준오차 분석 (Standard Error Analysis of Creep-Life Prediction Parameters of Type 316LN Stainless Steels)

  • 김우곤;윤송남;류우석
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.19-24
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    • 2004
  • A number of creep data were collected and filed for type 316LN stainless steels through literature survey and experimental data produced in KAERI. Using these data, polynomial equations for predicting creep life were obtained for Larson Miller (L-M), Qrr-Sherby-Dorn (O-S-D) and Manson-Haferd (M-H) parametric methods. In order to find out the suitability for them, the relative standard error (RSE) and standard error of estimate (SEE) values were obtained by statistical process of creep data. The O-S-D parameter showed better fitting to creep-rupture data than the L-M or the M-H parameters, and the three parametric methods did not generate the large difference in the SEE and the RSE values.

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새로운 등가회로정수 산출법에 의한 편측식 직선형 유도전동기의 동특성 해석 (Dynamics Analysis of Single-Sided Linear Induction Motor with New Method of Equivalent Circuit Parameter)

  • 장석명;권정기;조한욱;유대준;이성호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 B
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    • pp.1079-1081
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    • 2004
  • Linear induction motors are characterized by a large air gap and, as a result, large leakage inductances. Moreover, due to its unslotted structure and the absence of end rings in the secondary part, the equivalent circuit parameter calculation is very difficult. Therefore this paper introduces the new method of equivalent circuit parameter and analyzes dynamics characteristic of single-sided LIM

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공압 실린더의 신뢰성 평가를 위한 형상모수 추정에 관한 연구 (The Estimation of Shape Parameter of Pneumatic Cylinders)

  • 강보식;송창섭
    • 동력기계공학회지
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    • 제10권4호
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    • pp.127-132
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    • 2006
  • Pneumatic cylinders that are usually applied in the factory automation line have complicated failure cause because they are composed of various elements. In this study, we performed life test and performance test of double acting pneumatic cylinders according to the international standards and then analyzed the life and the main failure mode of the cylinders in the same load condition. On the basis of these processes, we can estimate shape parameter for the reliability estimation of pneumatic cylinders and their data analysis of life distribution.

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