• 제목/요약/키워드: Equivalent transformation

검색결과 188건 처리시간 0.031초

정현파 역기전력 특성을 갖는 브러시리스 동기전동기의 모델링 및 특성해석 (The Modelling and Characteristic Analysis of Brushless Synchronous Motor with Sinusoidal back EMF)

  • 김일남;백수현;김철진;맹인재;윤신용
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제49권6호
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    • pp.380-386
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    • 2000
  • This paper presents the mathematical modelling analysis of Brushless Synchronous Motor(BLSM). The dynamic and the steady state characteristics of BLSM are simulated and analyzed : electromagnetic torque, speed, line voltage, and current. We used mathematical modelling to model of BLSM with sinusoidal back EMF, namely the shaft transformation referencing rotor frame from a, b, c three to produce constant torque like synchronous motor. The experiment result has already similar to compare with simulation result : torque error about 7%, speed error about 5%. The validity of proposed modelling and analysis was confirmed by the experimental result.

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Modeling of Dynamic Loads Due to Pedestrian Walking

  • 김기철
    • 한국공간구조학회논문집
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    • 제5권1호
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    • pp.81-89
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    • 2005
  • Walking loads are influenced by various parameters so that they need to be measured considering such parameters. Walking frequency(rate) is experimentally investigated as the most important parameter in determining the walking load expressed with dynamic load factor. This study focuses on the derivation of continuous walking load-time functions at any walking frequency ranging from 1.30Hz to 2.70Hz. Experiments were conducted to obtain time-histories of walking loads at the increment of 0.1Hz, which are decomposed into harmonic loads by the Fourier transformation. The polynomial load-time functions are proposed representing the relationship between harmonic coefficients and walking frequencies, thereby easily formulating walking load-time histories for dynamic load factor with various walking frequencies.

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전기유압 속도제어 시스템의 귀환 선형화 제어 (Feedback linearization of the electro-hydraulic velocity control system)

  • 김영준;장효환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.1116-1121
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    • 1991
  • In this paper the feedback linearization of the valve-controlled nonlinear hydraulic velocity control system and the Implementation of the digital state feedback controller is studied. The C.inf. nonlinear transformation to the electro-hydraulic velocity control system, which transforms nonlinear system to linear equivalent one, is obtained. It is shown that this transformation Is global one. The digital controller to this linearized model is obtained by using the one-step ahead state estimator and implemented to real plant. The proposed method In this paper is easier to implement than other proposed methods and it is possible to control in real tine. The experiment and simulation study show that the implementation of the digital state feedback controller based on the feedback linearized model is successful.

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Equivalent classes of decouplable and controllable linear systems

  • Ha, In-Joong;Lee, Sung-Joon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.405-412
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    • 1992
  • The problem we consider in this paper is more demanding than the problem of input-output linearization with state equivalence recently solved by Cheng, Isidori, Respondek, and Tarn. We request that the MIMO nonlinear system, for which the problem of input-output linearization with state-equivalence is solvable, can be decoupled. In exchange for further requirement like this, our problem produces more usable and informative results than the problem of input-output linearization with state-equivalence. We present the necessary and sufficient conditions for our problem to be solvable. We characterize each of the nonlinear systems satisfying these conditions by a set of parameters which are invariant under the group action of state feedback and transformation. Using this set of parameters, we can determine directly the unique one, among the canonical forms of decouplable and controllable linear systems, to which a nonlinear system can be transformed via appropriate state feedback and transformation. Finally, we present the necessary and sufficient conditions for our problem to be solvable with internal stability, that is, for stable decoupling.

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SMV와 G.723.1 음성부호화기를 위한 파라미터 직접 변환 방식의 상호부호화 알고리듬 (Transcoding Algorithm for SMV and G.723.1 Vocoders via Direct Parameter Transformation)

  • 서성호;장달원;이선일;유창동
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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    • pp.2228-2231
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    • 2003
  • In this paper, a transcoding algorithm for the Selectable Mode Vocoder (SMV) and the G.723.1 speech coder via direct parameter transformation is proposed. In contrast to the conventional tandem transcoding algorithm, the proposed algorithm converts the parameters of one coder to the Other Without going through the decoding md encoding process. The proposed algorithm is composed of four parts: the parameter decoding, line spectral pair (LSP) conversion, pitch period conversion, excitation conversion and rate selection. The evaluation results show that the proposed algorithm achieves equivalent speech quality to that of tandem transcoding with reduced computational complexity and delay.

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THE METHOD OF ASYMPTOTIC INNER BOUNDARY CONDITION FOR SINGULAR PERTURBATION PROBLEMS

  • Andargie, Awoke;Reddy, Y.N.
    • Journal of applied mathematics & informatics
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    • 제29권3_4호
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    • pp.937-948
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    • 2011
  • The method of Asymptotic Inner Boundary Condition for Singularly Perturbed Two-Point Boundary value Problems is presented. By using a terminal point, the original second order problem is divided in to two problems namely inner region and outer region problems. The original problem is replaced by an asymptotically equivalent first order problem and using the stretching transformation, the asymptotic inner condition in implicit form at the terminal point is determined from the reduced equation of the original second order problem. The modified inner region problem, using the transformation with implicit boundary conditions is solved and produces a condition for the outer region problem. We used Chawla's fourth order method to solve both the inner and outer region problems. The proposed method is iterative on the terminal point. Some numerical examples are solved to demonstrate the applicability of the method.

버퍼 변환을 이용한 저면적 ISDB-T 시간 디인터리버 구조 (A Small-Area ISDB-T Time Deinterleaver Structure with Buffer Transformation)

  • 강형주
    • 한국항행학회논문지
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    • 제15권2호
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    • pp.227-233
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    • 2011
  • 본 논문에서는 저면적 ISDB-T 시간 디인터리버 구조를 제안하였다. ISDB-T는 일본과 중남미에서 많이 사용되고 있는 이동형 TV 표준으로써 긴 인터리빙을 이용하여 다른 표준에 비해 높은 성능을 보이고 있다. 그러나 긴 인터리빙을 구현하기 위해서는 많은 지연 버퍼가 필요하다. 지연 버퍼들은 주소 레지스터가 있어야 하므로 주소 레지스터의 개수도 많아진다. 본 논문에서는 디인터리버의 등가 변환을 통해 주소 레지스터의 개수를 크게 줄이는 구조를 제안하였다. 실험 결과를 통해 디인터리버의 면적을 줄일 수 있음을 확인할 수 있었다.

Sliding Mode Robust Control of Uncertain Delay Systems: Generalize Transformation Approach

  • Uahchinkul, K.;Ngamwiwit, J.;Phoojaruenchanachai, S.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.501-501
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    • 2000
  • In this paper, the theoretical development to stabilize a class of uncertain time-delay systems via sliding mode control is presented. The system under consideration is described in state space model containing state delay, uncertain parameters and disturbance. The main idea is to reduce the state of delayed system, by employing the generalize linear transformation, into an equivalent one with no delay inside, which is easier to analyze its behavior and stability. Then, the sliding control approach is employed to find the stabilizing control law. Finally, a numerical simulation is illustrated to show the algorithm for applying the proposed theorems and the efffetiveness of the designed control law in stabilizing the controlled systems.

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Nonlinear Aeroelastic Analysis of a High-Aspect-Ratio Wing with Large Deflection Effects

  • Kim, Kyung-Seok;Lim, In-Gyu;Lee , In;Yoo, Jae-Han
    • International Journal of Aeronautical and Space Sciences
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    • 제7권1호
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    • pp.99-105
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    • 2006
  • In this study, nonlinear static and dynamic aeroelastic analyses for a high-aspect-ratio wing have been performed. To achieve these aims, the transonic small disturbance (TSD) theory for the aerodynamic analysis and the large deflection beam theory considering a geometrical nonlinearity for the structural analysis are applied, respectively. For the coupling between fluid and structure, the transformation of a displacement from the structural mesh to the aerodynamic grid is performed by a shape function which is used for the finite element and the inverse transformation of force by work equivalent load method. To validate the current method, the present analysis results of a high-aspect-ratio wing are compared with the experimental results. Static deformations in the vertical and torsional directions caused by an angle of attack and gravity loading are compared with experimental results. Also, static and dynamic aeroelastic characteristics are investigated. The comparisons of the flutter speed and frequency between a linear and nonlinear analysis are presented.

Transformation of Rabbit Proximal Tubule Cells by Strontium Phosphate Transfection with a Plasmid Containing SV4O Early Region Genes

  • Han, Ho-Jae;Taub, Mary L.
    • The Korean Journal of Physiology
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    • 제28권2호
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    • pp.233-240
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    • 1994
  • In this study, it was investigated whether immortalized proximal tubule cells transformed with pRSVT could survive through the numerous passages. Results were as follows: 1. The cells transfected with pRSVT formed rapidly growing, multilayered colonies within 2 weeks in a hormone defined medium. Domes were also observed in some of the cultures. 2. r-glutamyl transpeptidase activity was equivalent to that observed in primary renal proximal tubule cell cultures. 3. Transformed cells with pRSVT form tubules in matrigel following 20 passages. 4. Genomic DNA of transformants was digested with either the restriction enzyme Xba or BamH1. A band of approximately 7.5kb was detected with Xba. Three BamH1 bands were detected at approximately 15 kb, 6.5 kb, and 3 kb.

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