NASA Scientific and Technical Aerospace Reports
NASA Scientific and Technical Aerospace Reports
NASA Scientific and Technical Aerospace Reports
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A family of Quantized State (QS) adaptive algorithms is introduced. These are computationally simple versions of the<br />
LMS adaptive algorithm <strong>and</strong> are useful in two ways as numerically fast implementations for adaptive tasks, <strong>and</strong> as a tool for<br />
studying the LMS algorithm in a quantized environment. Averaging theory is used to derive a persistence of excitation (PE)<br />
condition which guarantees exponential stability of one member of the QS family. Failure to meet this condition (which is not<br />
equivalent to the spectral richness PE condition for LMS) can result in exponential instability, even with the use of fixed<br />
leakage, showing that the stability properties of QS algorithms are heavily dependent on the character of the input sequence.<br />
Author<br />
Algorithms; Excitation; Failure<br />
20060001588 Rome Univ., Rome, Italy<br />
A Correlation Based Technique for Shift, Scale, <strong>and</strong> Rotation Independent Object Identification<br />
Capodiferro, I.; Cusani, R.; Jacovitti, G.; Vascotto, M.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal<br />
Processing (ICASSP ‘87); Volume 1; 1987, pp. 7.4.1-7.4.4; In English; See also 20060001583; Copyright; Avail.: Other<br />
Sources<br />
The technique of template matching in the log-polar visibility (magnitude of Fourier transform in the logarithmic radius<br />
<strong>and</strong> azimuth plane) is proposed as a promising tool for many problems of isolated object recognition irrespective of its<br />
position, scale, <strong>and</strong> rotation. The properties of the log-polar visibility suggests the use of partial information to implement<br />
some forms of ‘reduced template matching’. These techniques imply substantial reduction in the computational cost.<br />
Author<br />
Classifications; Pattern Recognition; Templates; Correlation; Fourier Transformation<br />
20060001591 Florida Univ., Gainesville, FL, USA<br />
Factors in Voice Quality: Acoustic Features Related to Gender<br />
Childers, D. G.; Wu, Ke; Hicks, D. M.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP<br />
‘87); Volume 1; 1987, pp. 8.2.1-8.2.4; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />
Attempts to measure the synthetic quality of speech usually consider the two factors intelligibility <strong>and</strong> naturalness, each<br />
involving subjective <strong>and</strong> objective characteristics. To generate high quality synthetic speech, spectral distortion should be<br />
avoided, spectral continuity <strong>and</strong> formant tracking should be done well. Glottal-related factors, including proper modeling of<br />
the 1) glottal excitation waveforms <strong>and</strong> 2) effects of source-tract interaction for synthesizers are discussed. Accurate detection<br />
of voiced/unvoiced/silent segments in the speech waveform <strong>and</strong> the fundamental frequency of voicing are also major concerns.<br />
We present both formal <strong>and</strong> informal listener evaluations of three synthesizers: LPC, formant <strong>and</strong> articulatory. Finally, we<br />
suggest a two-channel, speech <strong>and</strong> electroglottograph (EGG), approach to speech analysis to aid the automatic processing of<br />
speech.<br />
Author<br />
Speech Recognition; Frequencies; Intelligibility; Distortion; Waveforms; Excitation<br />
20060001592 Edinburgh Univ., UK<br />
A New Approach to Noise-Robust LPC<br />
Wrench, A. A.; Cowan, C. F. N.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87);<br />
Volume 1; 1987, pp. 8.5.1-8.5.3; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />
In this paper a new spectral estimate of noisy speech derived from linear predictive Autoregressive(AR) analysis is<br />
compared with the spectra produced by single order Linear Predictive Coding(LPC). The new estimate consists of a bin-by-bin<br />
average of a set of linear prediction AR spectra with orders between 10 <strong>and</strong> 30. According to simulation results the<br />
improvement in peak centre frequency <strong>and</strong> b<strong>and</strong>width estimation resulting from using this model for noisy speech is<br />
equivalent to increasing the SNR by about 5dB when the SNR of the input signal is 20dB or less.<br />
Author<br />
Linear Prediction; Coding; Frequencies; Spectra; B<strong>and</strong>width<br />
20060001611 Arizona State Univ., Tempe, AZ, USA<br />
Misadjustment Expressions for Infinite Impulse Response Adaptive Filters<br />
Sohie, Guy R. L.; Alshibani, Saud A.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP<br />
‘87); Volume 1; 1987, pp. 4.7.1-4.7.4; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />
Expressions are derived for the misadjustment in Infinite Impulse Response Adaptive filters. The decomposition method<br />
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