• Title/Summary/Keyword: Direct identification

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Volumetric Error Identification for NC Machine Tools Using the Reference Artifact (기준물을 이용한 NC 공작기계의 체적오차 규명)

  • Kim, Gyeong-Don;Jeong, Seong-Jong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.12
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    • pp.2899-2908
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    • 2000
  • Methodology of volumetric error identification is presented to improve the accuracy of NC machine tools by using a reference artifact and a touch trigger probe. Homogeneous transformation matrix and kinematic chain are used for modeling the geometric and thermal errors of a three-axis vertical machining center. The reference artifact is designed and fabricated to identify the model parameters by machine tool metrology. Parameters in the error model are able to be identified and updated by direct measurement of the reference artifact on the machine tool under the actual conditions which include the thermal interactions of error sources. The proposed method can speed up and simplify volumetric error identification processes.

System Identification on Flexure of SFRC (SFRC 휨거동에의 system identification)

  • 이차돈
    • Computational Structural Engineering
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    • v.4 no.3
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    • pp.99-106
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    • 1991
  • Flexural load-deflection relationships for steel fiber reinforced concrete(SFRC) are dependent on the tensile and compressive constitutive behaviors of the material, which may be refined in the presence of strain gradients under flexural loads. Considering the relatively large amount of flexural test results available for steel fiber reinforced concrete, and the relative ease of conducting such tests in comparison with direct tension tests, it seems to be important to obtain basic information on the tensile constitutive behavior of SFRC from the result of flexural tests. For this purpose "System Identification" technique was used for interpretating the flexural test data and it was successful in obtaining optimum sets of main parameters which explain the tensile constitutive behavior of SFRC under flexure.

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Robustness of Bimodal Speech Recognition on Degradation of Lip Parameter Estimation Performance (음성인식에서 입술 파라미터 열화에 따른 견인성 연구)

  • Kim, Jin-Young;Min, So-Hee;Choi, Seung-Ho
    • Speech Sciences
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    • v.10 no.2
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    • pp.27-33
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    • 2003
  • Bimodal speech recognition based on lip reading has been studied as a representative method of speech recognition under noisy environments. There are three integration methods of speech and lip modalities as like direct identification, separate identification and dominant recording. In this paper we evaluate the robustness of lip reading methods under the assumption that lip parameters are estimated with errors. We show that the dominant recording approach is more robust than other methods through lip reading experiments.

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A practical identification method for robot system dynamic parameters

  • Kim, Sung-wun
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.705-710
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    • 1989
  • A practical method of identifying the inertial parameters, viscous friction and Coulomb friction of a robot is presented. The parameters in the dynamic equations of a robot are obtained from the measurements of the command voltage and the joint position of the robot. First, a dynamic model of the integrated motor and manipulator is derived. An off line parameter identification procedure is developed and applied to the University of Minnesota Direct Drive Robot. To evaluate the accuracy of the parameters the dynamic tracking of robot was tested. The trajectory errors were significantly reduced when the identified dynamic parameters were used.

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A Practical Identification Method for Robot System Dynamic Parameters (로보트시스템 동적 변수의 실용적인 추정 방법)

  • Kim, Sungkwun
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.39 no.7
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    • pp.765-772
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    • 1990
  • A practical method of identifying the inertial parameters, viscous friction and Coulomb friction of a robot is presented. The parameters in the dynamic equations of a robot are obtained from the measurements of the command voltage and the joint position of the robot. First, a dynamic model of the integrated system of the mainpulator and motor is derived. An off-line parameter identification procedure is developed and applied to the University of Minnesota Direct Drive Robot. To evaluate the accuracy of the parameters the dynamic tracking of the robot was tested. The trajectroy errors were significantly reduced when the identified dynamic parameters were used.

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Antecedents of repurchasing intention toward fast fashion brands - Brand authenticity, brand identification, and brand love - (패스트 패션 브랜드 재구매의도의 선행변수 - 브랜드 진정성, 브랜드 동일시, 브랜드 사랑 -)

  • Park, Hye-Jung
    • The Research Journal of the Costume Culture
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    • v.28 no.2
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    • pp.147-165
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    • 2020
  • To identify the antecedents of repurchasing intention toward fast fashion brands, this study was conducted to examine brand authenticity and brand identification as both direct and indirect antecedents of repurchasing intention through fast fashion brand love. Through convenience sampling, 266 university students in Seoul metropolitan area completed a questionnaire survey. Data were analyzed using SPSS for exploratory factor analysis, and AMOS was used for confirmatory factor analysis and path analysis. Factor analysis revealed the following: for brand authenticity, four dimensions('originality,' 'reliability,' 'continuity,' and 'naturalness') were revealed; for both consumer brand identification and repurchase intention one dimension was revealed; and for brand love two dimensions were revealed('passion' and 'affection'). Path analysis confirmed that 'reliability' and 'naturalness'in relation to brand authenticity indirectly influenced repurchase intention through 'passion'(as a factor of brand love) and directly influenced repurchase intention. Further, 'continuity' in relation to brand authenticity indirectly influenced repurchase intention through 'affection'(as a factor of brand love) and directly influenced repurchase intention. Consumer brand identification influenced repurchase intention indirectly through two factors of brand love. These results suggest that fast fashion brand marketers should implement effective strategies that consider consumers'perceptions of brand authenticity, consumer brand identification, and brand love.

Self-expressive Roles of Family Restaurant Brands: Brand Personality-Self Image Congruence, Brand Identification, and Loyalty (패밀리레스토랑 브랜드의 자기 표현적 역할: 브랜드개성-자아이미지 일치성과 브랜드동일시, 및 충성도를 중심으로)

  • Jung, Hyo-Sun;Lee, In-Sook;Yoon, Hye-Hyun
    • Culinary science and hospitality research
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    • v.18 no.1
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    • pp.120-140
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    • 2012
  • The purpose of this study is to understand interrelationships among the congruence of brand personality of family restaurants with the self image of customers, brand identification, and loyalty. The results showed a positive relationship between congruence of brand personality of family restaurants with the self image of customers and brand identification. However, the congruence of brand personality of family restaurants with the self image of customers does not have a direct effect on brand loyalty, and congruence of self image with a pertinent brand is perceived through brand identification. In addition, it was found that the brand identification of family restaurants has a positive effect on brand loyalty. Limitations and future research directions are also discussed.

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Harmonic Analysis of the Effects of Inverter Nonlinearity on the Offline Inductance Identification of PMSMs Using High Frequency Signal Injection

  • Wang, Gaolin;Wang, Ying;Ding, Li;Yang, Lei;Ni, Ronggang;Xu, Dianguo
    • Journal of Power Electronics
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    • v.15 no.6
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    • pp.1567-1576
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    • 2015
  • Offline inductance identification of a permanent magnet synchronous motor (PMSM) is essential for the design of the closed-loop controller and position observer in sensorless vector controlled drives. On the base of the offline inductance identification method combining direct current (DC) offset and high frequency (HF) voltage injection which is fulfilled at standstill, this paper investigates the inverter nonlinearity effects on the inductance identification while considering harmonics in the induced HF current. The negative effects on d-q axis inductance identifications using HF signal injection are analyzed after self-learning of the inverter nonlinearity characteristics. Then, both the voltage error and the harmonic current can be described. In addition, different cases of voltage error distribution with different injection conditions are classified. The effects of inverter nonlinearities on the offline inductance identification using HF injection are validated on a 2.2 kW interior PMSM drive.

Target State Estimation by Direct Estimation of Maneuvering Input (기동입력의 직접추정에 의한 표적상태 추정)

  • Kim, Jong-Hwa;Lee, Man-Hyung;Hwang, Chang-Sun
    • Proceedings of the KIEE Conference
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    • 1989.07a
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    • pp.70-74
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    • 1989
  • To track the target trajectory with maneuvers, unknown maneuvering inputs must be estimated. To do this the direct estimation algorithm using generalized least square technique is developed based on the procedure of failure detection and identification(FDI) theory. Through the simulation using maneuvering target scenario, tracking performance and efficiency of the algorithm developed here are investigated.

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