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a product of two Toeplitz data matrices, as in the correlation method of linear prediction, then the Levinson recursions may<br />

be used to derive the Cybenko recursions, <strong>and</strong> the Cybenko recursions may be used to derive the Le Roux-Gueguen recursions.<br />

We explore the close relation between QR <strong>and</strong> Cholesky algorithms in the Toeplitz case <strong>and</strong> we compare their respective<br />

numerical properties when run in finite precision arithmetic.<br />

Author<br />

Algorithms; Cholesky Factorization; Operators; Matrix Theory<br />

20060001605 Oregon State Univ., Corvallis, OR, USA<br />

On Identification of Non-Gaussian Time Series<br />

Mohler, R. R.; Tang, Z.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87); Volume<br />

1; 1987, pp. 2.8.1-2.8.4; In English; See also 20060001583<br />

Contract(s)/Grant(s): N00014-81-K-6814; Copyright; Avail.: Other Sources<br />

Affine bilinear time series models AB(p,q) are considered here. An ‘inverse method’ is used to estimate model parameters.<br />

A non-anticipative AB(p,q) model could be transfered to 2p-1 dimension vector form (AB1,1) model. Simulation results for<br />

computer-generated <strong>and</strong> real data are given.<br />

Author<br />

Time Series Analysis; Numerical Analysis<br />

20060001606 University of Southern California, Los Angeles, CA, USA<br />

ARMA Modeling Using Cumulant <strong>and</strong> Autocorrelation Statistics<br />

Giannakis, G. B.; Mendel, J. M.; Wang, W.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing<br />

(ICASSP ‘87); Volume 1; 1987, pp. 2.9.1 - 2.9.4; In English; See also 20060001583<br />

Contract(s)/Grant(s): NSF ECS-85-01098; NSF ECS-86-02531; Copyright; Avail.: Other Sources<br />

One dimensional cumulant <strong>and</strong> autocorrelation output statistics are combined to form an overdetermined system of<br />

equations whose least-squares solution yields the coefficients of an ARMA model. The driving input noise is assumed to be<br />

non-Gaussian <strong>and</strong> white. The ARMA model is allowed to be non-minimum phase <strong>and</strong> even to contain all-pass factors. The<br />

special cases of AR <strong>and</strong> MA models are also included. The overdetermined nature of the method makes the solution practical<br />

for moderate output data lengths, when additive white Gaussian noise is considered. Simulations illustrate that our approach<br />

performs very well even at low signal-to-noise ratios.<br />

Author<br />

Autoregressive Moving Average; Autocorrelation; Simulation<br />

20060001607 BBN Systems <strong>and</strong> Technologies Corp., Cambridge, MA, USA<br />

A Stochastic Segment Model for Phoneme-Based Continuous Speech<br />

Roucos, S.; Dunham, M. O.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87);<br />

Volume 1; 1987, pp. 3.3.1-3.3.4; In English; See also 20060001583<br />

Contract(s)/Grant(s): N00014-85-C-0279; Copyright; Avail.: Other Sources<br />

Developing accurate <strong>and</strong> robust phonetic models for the different speech sounds is a major challenge for high performance<br />

continuous speech recognition. In this paper, we introduce a new approach, called the stochastic segment model, for modelling<br />

a variable-length phonetic segment X, an L-long sequence of feature vectors. The stochastic segment model consists of<br />

time-warping the variable-length segment X into a fixed-length segment Y called a resampled segment, <strong>and</strong> a joint density<br />

function of the parameters of the resampled segment Y, which in this work is assumed Gaussian. In this paper, we describe<br />

the stochastic segment model, the recognition algorithm, <strong>and</strong> the iterative training algorithm for estimating segment models<br />

from continuous speech. For speaker-dependent continuous speech recognition, the segment model reduces the word error rate<br />

by one third over a hidden Markov phonetic model.<br />

Author<br />

Phonemes; Speech Recognition; Stochastic Processes; Words (Language)<br />

20060001618 California Univ., Davis, CA, USA<br />

Object Classification <strong>and</strong> Registration by Radon Transform Based Invariants<br />

Dohse, Hans J.; Sanz, Jorge L. C.; Jain, Anil K.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing<br />

(ICASSP ‘87); Volume 1; 1987, pp. 7.5.1-7.5.4; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />

algorithm for object recognition which is based on translation <strong>and</strong> rotation invariant signatures is presented. The Radon<br />

162

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