• Title/Summary/Keyword: Random vectors

검색결과 150건 처리시간 0.023초

벡터 양자화에서 시간 평균 왜곡치의 수렴 특성 I. 대수 법칙에 근거한 이론 (The Convergence Characteristics of The Time- Averaged Distortion in Vector Quantization: Part I. Theory Based on The Law of Large Numbers)

  • 김동식
    • 전자공학회논문지B
    • /
    • 제33B권7호
    • /
    • pp.107-115
    • /
    • 1996
  • The average distortio of the vector quantizer is calcualted using a probability function F of the input source for a given codebook. But, since the input source is unknown in geneal, using the sample vectors that is realized from a random vector having probability function F, a time-average opeation is employed so as to obtain an approximation of the average distortion. In this case the size of the smple set should be large so that the sample vectors represent true F reliably. The theoretical inspection about the approximation, however, is not perfomed rigorously. Thus one might use the time-average distortion without any verification of the approximation. In this paper, the convergence characteristics of the time-average distortions are theoretically investigated when the size of sample vectors or the size of codebook gets large. It has been revealed that if codebook size is large enough, then small sample set is enough to obtain the average distortion by approximatio of the calculated tiem-averaged distortion. Experimental results on synthetic data, which are supporting the analysis, are also provided and discussed.

  • PDF

Joint-characteristic Function of the First- and Second-order Polarization-mode-dispersion Vectors in Linearly Birefringent Optical Fibers

  • Lee, Jae-Seung
    • Journal of the Optical Society of Korea
    • /
    • 제14권3호
    • /
    • pp.228-234
    • /
    • 2010
  • This paper presents the joint characteristic function of the first- and second-order polarization-modedispersion (PMD) vectors in installed optical fibers that are almost linearly birefringent. The joint characteristic function is a Fourier transform of the joint probability density function of these PMD vectors. We regard the random fiber birefringence components as white Gaussian processes and use a Fokker-Planck method. In the limit of a large transmission distance, our joint characteristic function agrees with the previous joint characteristic function obtained for highly birefringent fibers. However, their differences can be noticeable for practical transmission distances.

다중 랜덤 워커를 이용한 객체 추적 기법 (Visual Object Tracking by Using Multiple Random Walkers)

  • 문주혁;김한울;김창수
    • 방송공학회논문지
    • /
    • 제21권6호
    • /
    • pp.913-919
    • /
    • 2016
  • 본 논문에서는 다중 랜덤 워커(multiple random walkers)에 기반한 객체 추적 기법을 제안한다. 우선 서포트 벡터 머신(support vector machine)을 이용한 분류기 기반 객체 추적 기법을 소개한다. 다음으로 영상의 영역에 대한 특징 벡터 중 배경으로부터 추출된 특징 벡터를 억제하는 기법을 제안한다. 영역에서 배경 요소를 찾기 위해 다중 랜덤 워커를 이용한 전경 및 배경 추출 방법을 제시한다. 배경 요소가 억제된 특징 벡터를 이용하여 학습된 서포트 벡터 머신은 객체와 배경이 유사한 영상, 객체가 다른 물체에 의해 가려지는 영상 등에서 객체와 배경을 확실하게 구분하고, 추적 알고리즘은 정확한 객체 추적을 수행한다. 또한, 객체 추적 알고리즘의 응용에서 중요한 속도 문제를 크게 개선하는 방법을 제안한다. 마지막으로 실험을 통해 제안하는 기법이 높은 처리 속도를 유지하면서 동시에 기존 기법보다 우수한 추적 성능을 보임을 확인한다.

Local Limit Theorem for Large Deviations

  • So, Beong-Soo;Jeon, Jong-Woo
    • Journal of the Korean Statistical Society
    • /
    • 제13권2호
    • /
    • pp.81-86
    • /
    • 1984
  • Under the i.i.d. hypothesis, authors (1982, 1984) proved some local limit theorems both for the continuous case and for the lattice case. In this paper, results are extended to the case where the random vectors are not identically distributed.

  • PDF

On the Distribution of the Scaled Residuals under Multivariate Normal Distributions

  • Cheolyong Park
    • Communications for Statistical Applications and Methods
    • /
    • 제5권3호
    • /
    • pp.591-597
    • /
    • 1998
  • We prove (at least empirically) that some forms of the scaled residuals calculated from i.i.d. multivariate normal random vectors are ancillary. We further show that, if the scaled residuals are ancillary, then they have the same distribution whatever form of rotation is rosed to remove sample correlations.

  • PDF

DEPENDENCE IN M A MODELS WITH STOCHASTIC PROCESSES

  • KIM, TAE-SUNG;BAEK, JONG-IL
    • 호남수학학술지
    • /
    • 제15권1호
    • /
    • pp.129-136
    • /
    • 1993
  • In this paper we present of a class infinite M A (moving-average) sequences of multivariate random vectors. We use the theory of positive dependence to show that in a variety of cases the classes of M A sequences are associated. We then apply the association to establish some probability bounds and moment inequalities for multivariate processes.

  • PDF

A NOTE ON FELLER`S THEOREM

  • Hong, dug-Hun
    • 대한수학회논문집
    • /
    • 제14권2호
    • /
    • pp.425-428
    • /
    • 1999
  • In this note we have generalization of Feller`s theorem to real separable Banach spaces, from which we obtain easily Chow-Robbins “fair" games problem in the Banach spaces.aces.

  • PDF

A CENTRAL LIMIT THEOREM FOR THE STATIONARY MULTIVARIATE LINEAR PROCESS GENERATED BY ASSOCIATED RANDOM VICTORS

  • Kim, Tae-Sung;Ko, Mi-Hwa;Chung, Sung-Mo
    • 대한수학회논문집
    • /
    • 제17권1호
    • /
    • pp.95-102
    • /
    • 2002
  • A central limit theorem is obtained for a stationary multivariate linear process of the form (equation omitted), where { $Z_{t}$} is a sequence of strictly stationary m-dimensional associated random vectors with E $Z_{t}$ = O and E∥ $Z_{t}$$^2$ < $\infty$ and { $A_{u}$} is a sequence of coefficient matrices with (equation omitted) and (equation omitted).ted)..ted).).