• Title/Summary/Keyword: Coefficient identification

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Identification of Abnormal Compressor using Wavelet Transform (Wavelet 변환에 의한 압축기의 이상상태 식별)

  • 정지홍;이기용;김정석;이감규
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.361-364
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    • 1995
  • Wavelet Transform is a new tools for signal processing, such as data compressing extraction of parameter for Reconition and Diagnostics. This transform has an advandage of a good resolution compared to Fast Fourier Transform (FFT) In this study, we employ the wavelet transform for analysis of Acoustic Emission raw signal generated form rotary compressor. In abnormal condition of rotary compressor, the state of operating condition can be classified by analizing coefficient of wavelet transformed signal.

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A study on the system identification technique for hydrodynamic coefficient estimation of underwater submersible (수중운동체의 유체계수 추정을 위한 시스템 식별기법 연구)

  • 양승윤;최중락;김흥렬
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.772-775
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    • 1992
  • It is necessary to estimate hydrodynamic coefficients to design the auto-pilot system and motion simulator of submersible vehicle. In this paper, an algorithm was designed to estimate hydrodynamic coefficients of submersible vehicle. Using this algorithm, the hydrodynamic coefficients were estimated from measurements of full scale trial. The estimated hydrodynamic coefficients were used for the design of an auto-depth controller(ADC) of submersible vehicle, and the resulting ADC are proved to have a better performance than the previous one.

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Identification of Linear Structural Systems (선형 구조계의 동특성 추정법)

  • 윤정방
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1989.10a
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    • pp.46-50
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    • 1989
  • Methods for the estimation of the coefficient matrices in the equation of motion for a linear multi-degree-of-freedom structure arc studied. For this purpose, the equation of motion is transformed into an auto-regressive and moving average with auxiliary input (ARMAX) model. The ARMAX parameters are evaluated using several methods of parameter estimation; such as toe least squares, the instrumental variable, the maximum likelihood and the limited Information maximum likelihood methods. Then the parameters of the equation of motion are recovered therefrom. Numerical example is given for a 3-story building model subjected to an earthquake exitation.

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Model Reference Adaptive Control for Linear System with Improved Convergence Rate-parameter Adaptation Method (선형시스템을 위한 개선된 수렴속도를 갖는 기준모델 적응제어)

  • Lim, Kye-Young
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.37 no.12
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    • pp.884-893
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    • 1988
  • Adaptive controllers for linear unknown coefficient system, that is corrupted by disturbance, are designed by parameter adaptation model reference adaptive control(MRAC). This design is stemmed from the Lyapunov direct method. To reduce the model following error and to improve the convergence rate of the design, an indirect-suboptimal control law is derived. Proper compensation for the effects of time-varying coefficients and plant disturbance are suggested. In the design procedure no complete identification of unknown coefficients are required.

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Self-Commissioning for Surface-Mounted Permanent Magnet Synchronous Motors

  • Urasaki, Naomitsu;Senjyu, Tomonobu;Uezato, Katsumi
    • Journal of Power Electronics
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    • v.3 no.1
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    • pp.33-39
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    • 2003
  • This paper presents the self-commissioning for surface-mounted permanent magnet synchronous motor. The proposed strategy executes three tests with a vector controlled inverter drive system. To do this, synchronous d-q axes currents are appropriately controlled for each test. From the three tests, armature resistance, armature inductance, equivalent iron loss resistance, and emf coefficient are identified automatically. The validity of the proposed strategy is confirmed by experimental results.

A Study on the Reliability and Factor analysis of Pattern Identification for Tic Disorders in children (틱(Tic) 장애의 한의변증유형 설문지에 대한 신뢰도 및 요인분석 연구)

  • Wei, Young-Man;Lee, Go-Eun;Jung, Song-Hwa;Lee, Hee-Kyung;Lyu, Yeoung-Su;Kang, Hyung-Won
    • Journal of Oriental Neuropsychiatry
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    • v.23 no.1
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    • pp.59-82
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    • 2012
  • Objectives : We purposed to objectify the pattern diagnosis of Tic disorders through factor and reliability analysis regarding a pattern identification questionnaire concerning Tic disorders in children. Methods : We chose and studied 144 children who were pattern-diagnosed out of 200 tic disordered children who visited H hospital in Seoul from January 2006 to April 2011. Results : 1. TTD (50%) was the most common type and the occurrence rate in male children was higher(4.76:1). Also, the rate of hospital visits was highest at the age 8(23.6%). 2. In results concering pattern diagnosis, Gan-poong-nae-dong was most frequently diagnosed in 53 patients (36.8%), and Dam-hwa-yo-sin (42 patients), Gan-sin-um-her (30 patients), and Bee-her-gan-wang (6 patients). 3. In an attempt to verify the reliability of the questionnaire, the coefficient regarding the whole questions (Cronbach ${\alpha}$) came to 0.909. Moreover, the reliability coefficient foreach sub factor was 0.687 in Ganpoong-nae-dong, 0.817 in Dam-hwa-yo-sin, 0.851 in Bee-her-gan-wang, and 0.726 in Gan-sin-um-her, respectively. Thus, their consistency was ensured. 4. In exploratory factor analysis concerning the most common five questions in the questionnaire, the questions of Dam-hwa-yo-sin and Gan-poong-nae-dong appeared to be part of different factors. While, Gan-sin-um-her and Bee-her-gan-wang questions showed that they belong to the same factors. 5. In factor analysis excluding both Gan-sin-um-her and Bee-her-gan-wang questions, both showed significant results; however, the one excluding Gan-sin-um-her showed improved results. Conclusions : From the above results concerning the Pattern Identification Questionnaire for Tic Disordered children, three separated patterns of Bee-her-gan-wang, Dam-hwa-yo-sin, Gan-poong-nae-dong are thought to be available for clinical use. However, further validity studies are needed.

Analysis of Clinical Indicators related to Pattern-Identification in Acute Cerebral Infarction Patient (급성기 뇌경색 환자에 있어 변증형별 유의한 임상지표의 분석)

  • Lee, Eun-chan;Hyun, Sang-ho;Kwak, Seung-hyuk;Woo, Su-kyung;Park, Ju-young;Jung, Woo-sang;Moon, Sang-kwan;Cho, Ki-ho;Park, Sung-wook;Ko, Chang-nam
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.13 no.1
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    • pp.33-42
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    • 2012
  • Object : The aim of this study was to assess the clinical indicators related to Pattern-Identification(PI) in acute cerebral infarction patients. Methods : We studied hospitalized patients within 30days after ictus, who admitted at Korean Medicine Center of Kyung-Hee University from January 2010 to October 2012.(n=290) Two Traditional Korean Medicine(TKM) physicians evaluated the patients independently and diagnosed PI. Inter-rater reliability was measured using simple percentage agreement and the Cohen's kappa(κ) coefficient. To assess the clinical indicators closely related to each PI, we analysed average score of each indicator in each group. Results : Simple percentage agreement of PI between raters was 64.83% and Cohen's kappa(κ) coefficient was 0.526(95% CI: 0.451-0.600). Inter-rater reliability level was fair to good. We analysed the clinical indicators in each group. Significant indicators for Fire-Heat Pattern(FHP) were reddened complexion and strong pulse power, and meaningful indicators for FHP were halitosis and thick tongue fur. Significant indicator for Dampness-Phlegm Pattern(DPP) was overweight and there was no meaningful indicator. Significant indicator for Yin-Deficiency Pattern(YDP) was dry tongue fur and meaningful indicator for YDP was thirst. There was no significant indicator for Qi-Deficiency Pattern(QDP) and pale complexion and faint low voice were meaningful indicators for QDP. Conclusions : This study reveals the significant and meaningful clinical indicators related to each Pattern-Identification in acute cerebral infarction patients. It will contribute to standardization of Korean Medical Diagnosis and Treatment in acute cerebral infarction patients.

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Palmprint Identification Algorithm using Hu Invariant Moments (Hu 불변 모멘트를 이용한 장문인식 알고리즘)

  • SHIN Kwang Gyu;RHEE Kang Hyeon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.42 no.2 s.302
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    • pp.31-38
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    • 2005
  • Recently, Biometrics-based personal identification is regarded as an effective method of person's identity with recognition automation and high performance. In this paper, the palmprint recognition method based on Hu invariant moment is proposed. And the low-resolution(750dpi) palmprint image$(5.5Cm\times5.5Cm)$ is used for the small scale database of the effectual palmprint recognition system. The proposed system is consists of two parts: firstly, the palmprint fixed equipment for the acquisition of the correctly palmprint image and secondly, the algorithm of the efficient processing for the palmprint recognition. And the palmprint identification step is limited 3 times. As a results, when the coefficient is 0.001 then FAR and GAR are $0.038\%$ and $98.1\%$ each other. The authors confirmed that FAR is improved $0.002\%$ and GAR is $0.1\%$ each other compared with [3].

Speaker Identification Using Dynamic Time Warping Algorithm (동적 시간 신축 알고리즘을 이용한 화자 식별)

  • Jeong, Seung-Do
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.5
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    • pp.2402-2409
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    • 2011
  • The voice has distinguishable acoustic properties of speaker as well as transmitting information. The speaker recognition is the method to figures out who speaks the words through acoustic differences between speakers. The speaker recognition is roughly divided two kinds of categories: speaker verification and identification. The speaker verification is the method which verifies speaker himself based on only one's voice. Otherwise, the speaker identification is the method to find speaker by searching most similar model in the database previously consisted of multiple subordinate sentences. This paper composes feature vector from extracting MFCC coefficients and uses the dynamic time warping algorithm to compare the similarity between features. In order to describe common characteristic based on phonological features of spoken words, two subordinate sentences for each speaker are used as the training data. Thus, it is possible to identify the speaker who didn't say the same word which is previously stored in the database.

Correlations between Sperm Motility, SCSA (Sperm Chromatin Structure Assay), Reproductive Performance and Heterospermic Fertility in Boars

  • Kim, In-Cheul;Ryu, Jae-Weon;Cho, Kyu-Ho;Hong, Joon-Ki;Choi, Eun-Ji;Choi, Bong-Hwan;Park, Jun-Cheol;Moon, Hong-Kil;Son, Jung-Ho
    • Reproductive and Developmental Biology
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    • v.32 no.2
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    • pp.127-133
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    • 2008
  • The objective of this study was two folds: to investigate the relationship between paternal identification rate and sperm quality parameters such as motility and sperm chromatin structure assay after heterospermic insemination; to see if mutual complement between tests and development of useful technique to enhance the fertility in artificial insemination. In individual boar's fertilizing ability, 3 high fertility boars showed significantly high fertility (p<0.05) compared to 3 low fertility boars, but there was no difference in litter size between two groups. Sperm motility test in pooled and individual semen using computer assisted sperm analysis (CASA) revealed that no significant difference among boars. The high fertile boar showed tendency of low %Red (High red fluorescence/green+red fluorescence) in sperm chromatin structure assay (SCSA) but paternal identification rate from piglets did not differ after heterospermic insemination. The correlation coefficient between individual or pooled semen function test and farrowing rates were well correlated as follows: %Red with litter size (r= - 0.53, p=0.03); %Red with paternal identification rates (r=-0.51, p=0.03); paternal identification rates with litter size (r=0.57, p=0.02). These results indicate that sperm chromatin structure assay and sperm quality parameter test in pooled semen are useful method to predict and evaluate the fertilizing capacity after heterospermic insemination in boars.