• Title/Summary/Keyword: Identification test

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In-situ modal testing and parameter identification of active magnetic bearing system by magnetic force measurement and the use of directional frequency response functions (전자기력 측정과 방향성주파수 응답함수를 이용한 능동 자기베어링 시스템의 운전중 모드시험 및 매개변수 규명)

  • Ha, Young-Ho;Lee, Chong-Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.7
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    • pp.1156-1165
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    • 1997
  • Complex modal testing is employed for the in-situ parameter identification of a four-axis active magnetic bearing system while the system is in operation. In the test, magnetic bearings are used as exciters as well as actuators for feedback control. The experimental results show that the directional frequency response function, which is properly defined in the complex domain, is a powerful tool for identification of bearing as well as modal parameters. It is also shown that the position and current stiffnesses can be accurately estimated using the relations between the measured forces, displacements, and currents.

Identification of Asymmetry in General Rotors from Directional Frequency Response Functions (방향성 주파수 응답 함수를 이용한 일반 회전체의 비대칭성 규명)

  • Seo, Yun-Ho;Kang, Sung-Woo;Lee, Chong-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.941-944
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    • 2005
  • Asymmetry of rotor systems is an important factor for identification of dynamic characteristics including the stability and response of rotors and for condition monitoring. In this work, asymmetry of rotors is identified by applying curve-fitting method to the directional frequency response functions (dFRFs), which are known as a powerful tool for detecting the presence and degree of asymmetry. This method minimizes least square error between analytical and measured dFRFs by iteratively updating physical parameters associated with rotor asymmetry. The effectiveness of the identification method is demonstrated by experiments with a laboratory test rotor.

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Implementation and Evaluation of the Wibro-based Location Identification System for Air Base Protection Force (Wibro 기반 비행기지 방어전력 위치식별체계 구축 및 실험)

  • Pyo, Sang-Ho;Koo, Jung;Ko, Young-Bae;Kim, Ki-Hyung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.3
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    • pp.306-314
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    • 2012
  • This paper proposes a new system to maximize efficiency of Air Base Protection Operations through the development of location identification software. The Wibro-based location identification system for Air Base Protection Force offers Blue Ground Force digitalized character message which is not exposed to enemy. Also, it is possible to automatically provide the location of Blue Ground Force to Air Base Ground Operations Center. The test result proves that this system is very helpful when Air Base Protection Force executes Air Base Protection Operations.

Identification of Connection Stiffnesses of Bolted Structures Using a Substructural Sensitvitity Analysis (부분구조 기반 민감도 해석을 이용한 볼트겹합 구조물의 결합강성 추정)

  • 서세영;방극호;김찬묵;이두호
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.11 no.7
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    • pp.287-294
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    • 2001
  • The identification of connection stiffnesses of bolted structures is presented using FRT-based substructural sensitivity analysis. The substructural design sensitivity formula is derived and plugged into the optimization module of MATLAB to identify connection stiffnesses of an air-conditioner compressor or passenger Car. The air-conditioner composed of a compressor and a bracket, is analysed by using the FRT-based substructural(FBS) method to obtain FTRs an FE model is generated for the bracket, and the impact hammer test is performed for the compressor, Obtained FRTs are combined to calculate the reaction force at the connection point and the system response. By minimizing the difference between a target FRT and calculated one the connection element properties of the air-conditioner syste are identified It is shown that the proposed identification method is effective for a real problem.

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A study on the Fuzzy Identification System for the Analysis of Equilibrium Sense (평형감 평가를 위한 퍼지 판독 시스템에 관한 연구)

  • Lim, Hyung-Soon;Im, Jeong-Heum;Lee, Chang-Goo
    • Proceedings of the KIEE Conference
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    • 1999.11c
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    • pp.815-817
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    • 1999
  • In this paper, we developed a fuzzy identification system to evaluate sensation of equilibrium objectively and quantitatively. By using caloric test. we estimated ECG(electro-cardiogram) and EOG(electro-oculogram), which were biomedical signals related to sensation of equilibrium, and used them as inputs of fuzzy identification system input. Fuzzy identification system analyzed the relationality between biomedical signals and sensation of equilibrium automatically, and evaluated it taking the co-relation between these signals into consideration.

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Integrated Damage Identification System for large Structures via Vibration Measurement

  • JEONG-TAE KIM;SOO-YONG PARK;JAE-WOONG YUN;JONG-HOON BAEK
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • v.4 no.1
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    • pp.31-37
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    • 2001
  • In this paper, an integrated damage identification system (IDIS) is proposed to locate and size damage in real structures. The application of the IDIS to real structures includes the measurement of modal responses, the construction of damage-detection models, and the implementation of measurements and models into the damage-detection process. Firstly, the theory of the damage identification method is outlined. Secondly, the schematic and each component of the IDIS are described. Finally, the practicality of the IDIS is verified from experiments on two different bridge-models, a model plate-grider and a model truss.

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A Practical Method for Identification of Nonlinear Chemical Processes by use of Volterra Kernel Model

  • Numata, Motoki;Kashiwagi, Hiroshi;Harada, Hiroshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.145-148
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    • 1999
  • It is known that Volterra kernel models can represent a wide variety of nonlinear chemical processes. Also, it is necessary for Volterra model identification to excite the process to be identified with a signal having wide range of frequency spectrum and high enough amplitude of input signals. Kashiwagi[4 ∼ 7] has recently shown a method for measuring Volterra kernels up to third order using pseudorandom M-sequence signals. However, in practice, since it is not always possible to apply such input sequences to the actual chemical plants. Even when we can apply such a pseudorandom signal to the process, it takes much time to obtain higher order Volterra kernels. Considering these problems, the authors propose here a new method for practical identification of Volterra kernels by use of approximate open differential equation (ODE) model and simple plant test. Simulation results are shown for verifying the usefulness of our method of identification of nonlinear chemical processes.

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Nonlinear identification of Bouc-Wen hysteretic parameters using improved experience-based learning algorithm

  • Luo, Weili;Zheng, Tongyi;Tong, Huawei;Zhou, Yun;Lu, Zhongrong
    • Structural Engineering and Mechanics
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    • v.76 no.1
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    • pp.101-114
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    • 2020
  • In this paper, an improved experience-based learning algorithm (EBL), termed as IEBL, is proposed to solve the nonlinear hysteretic parameter identification problem with Bouc-Wen model. A quasi-opposition-based learning mechanism and new updating equations are introduced to improve both the exploration and exploitation abilities of the algorithm. Numerical studies on a single-degree-of-freedom system without/with viscous damping are conducted to investigate the efficiency and robustness of the proposed algorithm. A laboratory test of seven lead-filled steel tube dampers is presented and their hysteretic parameters are also successfully identified with normalized mean square error values less than 2.97%. Both numerical and laboratory results confirm that, in comparison with EBL, CMFOA, SSA, and Jaya, the IEBL is superior in nonlinear hysteretic parameter identification in terms of convergence and accuracy even under measurement noise.

Parameters Comparison in the speaker Identification under the Noisy Environments (화자식별을 위한 파라미터의 잡음환경에서의 성능비교)

  • Choi, Hong-Sub
    • Speech Sciences
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    • v.7 no.3
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    • pp.185-195
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    • 2000
  • This paper seeks to compare the feature parameters used in speaker identification systems under noisy environments. The feature parameters compared are LP cepstrum (LPCC), Cepstral mean subtraction(CMS), Pole-filtered CMS(PFCMS), Adaptive component weighted cepstrum(ACW) and Postfilter cepstrum(PF). The GMM-based text independent speaker identification system is designed for this target. Some series of experiments show that the LPCC parameter is adequate for modelling the speaker in the matched environments between train and test stages. But in the mismatched training and testing conditions, modified parameters are preferable the LPCC. Especially CMS and PFCMS parameters are more effective for the microphone mismatching conditions while the ACW and PF parameters are good for more noisy mismatches.

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A Study of Blood Group Identification with Teeth Left Standing at a High Temperature (온도변화가 치아경조직에서 혈형물질 검출에 미치는 영향에 관한 실험적 연구)

  • 최영철;김종열
    • Journal of Oral Medicine and Pain
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    • v.7 no.1
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    • pp.77-85
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    • 1982
  • Identification of blood group from dental hard tissue for the purpose of individual identification of a highly burned corpse would play a significant role in a practical legal medicine. The author conducted a study of blood group with teeth left stading at a high temperature by the method of elution test. The following results were obtained. 1. The blood identifcation from heated dental hard tissue proved to be possible. 2. In cases of heat-treated theeth at $100^{\circ}C$ for 120 minutes, at $150^{\circ}C$ for 120 minutes and at $200^{\circ}C$ for 45 minutes for A.B.O(H) blood group, the identification of blood group was possible. 3. In case of heat-treated teeth, thermostability of blood group was found to be $150^{\circ}C$. 4. The adequate surface area for the detection of blood group was 40-80 meshes.

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