• 제목/요약/키워드: Uncorrelation

검색결과 9건 처리시간 0.025초

공구파손검출을 위한 시스템인식에 관한 연구 (A Study on the System Identification for Detection of Tool Breakage)

  • 사승윤
    • 한국생산제조학회지
    • /
    • 제9권5호
    • /
    • pp.144-149
    • /
    • 2000
  • The demands for robotic and automatic system are continually increasing in manufacturing fields. There have been many studies to monitor and predict the system, but they have mainly focused upon measuring cutting force, and current of motor spindle, and upon using acoustic sensor, etc. In this study, time series sequence of cutting force was acquired by taking advantage of piezoelectric type tool dynamometer. Radial cutting force was obtained from it and was available for useful observation data. The parameter was estimated using PAA(parameter adaptation algorithm) from observation data. ARMA(auto regressive moving average) model was selected for system model and second order was decided according to parameter estimation. Uncorrelation test was also carried out to verify convergence of parameter.

  • PDF

선삭가공에서 공구파손 검출 시스템 인식에 관한 연구 (A Study on the System Identification of Tool Breakage Detection in Turning)

  • 사승윤
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
    • /
    • pp.40-45
    • /
    • 1999
  • The demands for robotic and automatic system are continually increasing in manufacturing fields. There have been many studies to monitor and predict the system, but they have mainly focused upon measuring cutting force, and current of motor spindle, and upon using acoustic sensor, etc.In this study, time series sequence of cutting force was acquired by taking advantage of piezoelectric type tool dynamometer. Radial cutting force was obtained from it and was available for useful observation data. The parameter was estimated using PAA (parameter adaptation algorithm) from observation data. ARMA(auto regressive moving average) model was selected for system model and second order was decided according to parameter estimation. Uncorrelation test was also carried out to verify convergence of parameter.

  • PDF

비선형 분산 광 전송 매질에 있어서 인접 광 솔리톤간의 신뢰도 및 최대 전송거리 분석 (Reliability and maximum transmission length analysis between adjacent optical solitons in nonlinear dispersive transmission materials)

  • 변승우;김종규;송재원
    • E2M - 전기 전자와 첨단 소재
    • /
    • 제9권3호
    • /
    • pp.246-250
    • /
    • 1996
  • In optical soliton transmission systems with nonlinear dispersive materials, which is utilized for ultra-long and high bit rate transmission, it is shown that the value of initial time difference between adjacent solitons is analyzed for optimum bit rate. The method is inducted by uncorrelation condition with minimum interaction forces in initial covariance coefficient between adjacent solitons. When the initial time difference is 6 times of soliton pulse width by the results, it is shown that the reliability is maintained with more than 90% within transmission length of soliton period. multiplied by 93.

  • PDF

단일 대상의 fMRI 데이터에서 제약적 교차 최소 제곱 비음수 행렬 분해 알고리즘에 의한 활성화 뇌 영역 검출 (Detecting Active Brain Regions by a Constrained Alternating Least Squares Nonnegative Matrix Factorization Algorithm from Single Subject's fMRI Data)

  • ;이종환;이성환
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(C)
    • /
    • pp.393-396
    • /
    • 2011
  • In this paper, we propose a constrained alternating least squares nonnegative matrix factorization algorithm (cALSNMF) to detect active brain regions from single subject's task-related fMRI data. In cALSNMF, we define a new cost function which considers the uncorrelation and noisy problems of fMRI data by adding decorrelation and smoothing constraints in original Euclidean distance cost function. We also generate a novel training procedure by modifying the update rules and combining with optimal brain surgeon (OBS) algorithm. The experimental results on visuomotor task fMRI data show that our cALSNMF fits fMRI data better than original ALSNMF in detecting task-related brain activation from single subject's fMRI data.

시스템인식을 이용한 공구파손 검출 (Tool Fracture Detection Using System Identification)

  • 사승윤
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 1996년도 춘계학술대회 논문집
    • /
    • pp.119-123
    • /
    • 1996
  • The demands for robotic and automatic system are continually increasing in manufacturing fields. There were so many studies to monitor and predict system, but it were mainly relied upon measuring of cutting force, current of motor spindle and using acoustic sensor, etc. In this study digital image of time series sequence was acquired taking advantage of optical technique. Then, mean square error was obtained from it and was available for useful observation data. The parameter was estimated using PAA(parameter adaptation algorithm) from observation data. AR model was selected for system model, fifth order was decided according to parameter estimation. Uncorrelation test was also carried out to verify convergence of parameter. Through the proceedings, we found there was a system stability.

  • PDF

Exact Outage Probability Analysis of Proactive Relay Selection in Cognitive Radio Networks with MRC Receivers

  • Ho-Van, Khuong
    • Journal of Communications and Networks
    • /
    • 제18권3호
    • /
    • pp.288-298
    • /
    • 2016
  • Proactive relay selection in cognitive radio networks has recently received considerable attention. However, its outage probability analysis is limited to partially-identical fading distributions, uncorrelation among received signal-to-noise ratios (SNRs), and no direct channel. This paper completes this literature deficiency by generalizing the existing analysis for non-identical fading distributions, correlation among received SNRs, and with direct channel. Numerous results demonstrate that relay selection with a direct channel achieves a higher diversity order and superior performance than that without a direct channel at virtually no cost of power and bandwidth. Further, proactive relay selection suffers an error floor at either a large maximum transmit power or large maximum interference power; however, the error floor level can be significantly remedied with an increase in the number of relays.

시스템인식을 이용한 공구파손검출 알고리듬에 관한 연구 (A Study on the Tool Fracture Detection Algorithm Using System Identification)

  • 사승윤;유은이;유봉환
    • 대한기계학회논문집A
    • /
    • 제21권6호
    • /
    • pp.988-994
    • /
    • 1997
  • The demands for robotic and automatic system are continually increasing in manufacturing fields. There have been many studies to monitor and predict the system, but they have mainly focused upon measuring cutting force, and current of motor spindle, and upon using acoustic sensor, etc. In this study, digital image of time series sequence was acquired by taking advantage of optical technique. Mean square error was obtained from it and was available for useful observation data. The parameter was estimated using PAA(parameter adaptation algorithm) from observation data. AR(auto regressive) model was selected for system model and fifth order was decided according to parameter estimation. Uncorrelation test was also carried out to verify convergence of parameter. Through the proceedings, it was found that there was a system stability.

균형불완비블록설계의 혼합효과에서 블록간 정보 (Interblock Information from BIBD Mixed Effects)

  • 최재성
    • 응용통계연구
    • /
    • 제28권2호
    • /
    • pp.151-158
    • /
    • 2015
  • 본 논문은 균형불완비블록설계(balanced incomplete block design)에서 사영에 근거한 블록내(intrablock) 분석과 블록간(interblock) 분석을 다루고 있다. 블록간 분석을 위한 행렬모형을 제시하고 블록간 추정벡터를 구하는 방법을 다루고 있다. 처리효과의 블록내 추정벡터와 블록간 추정벡터의 분산공분산행렬을 규명하고 공분산행렬의 구조적 특성으로 두 추정벡터 간에 상관성이 없음을 보여주고 있다. 처리효과의 상관성없는 두 추정벡터를 이용한 결합추정에서 가중치를 구하는 방법으로 공분산행렬을 이용할 수 있음을 다루고 있다. 또한 처리효과에 적합된 블록변동량의 계산은 상수적합법을 이용한 블록제곱합과 일치함을 보여주고 있다.