6,428 research outputs found
Bayesian Method of Moments (BMOM) Analysis of Mean and Regression Models
A Bayesian method of moments/instrumental variable (BMOM/IV) approach is
developed and applied in the analysis of the important mean and multiple
regression models. Given a single set of data, it is shown how to obtain
posterior and predictive moments without the use of likelihood functions, prior
densities and Bayes' Theorem. The posterior and predictive moments, based on a
few relatively weak assumptions, are then used to obtain maximum entropy
densities for parameters, realized error terms and future values of variables.
Posterior means for parameters and realized error terms are shown to be equal
to certain well known estimates and rationalized in terms of quadratic loss
functions. Conditional maxent posterior densities for means and regression
coefficients given scale parameters are in the normal form while scale
parameters' maxent densities are in the exponential form. Marginal densities
for individual regression coefficients, realized error terms and future values
are in the Laplace or double-exponential form with heavier tails than normal
densities with the same means and variances. It is concluded that these results
will be very useful, particularly when there is difficulty in formulating
appropriate likelihood functions and prior densities needed in traditional
maximum likelihood and Bayesian approaches.Comment: 14 pages, postscript and pdf forma
Pauses and the temporal structure of speech
Natural-sounding speech synthesis requires close control over the temporal structure of the speech flow. This includes a full predictive scheme for the durational structure and in particuliar the prolongation of final syllables of lexemes as well as for the pausal structure in the utterance. In this chapter, a description of the temporal structure and the summary of the numerous factors that modify it are presented. In the second part, predictive schemes for the temporal structure of speech ("performance structures") are introduced, and their potential for characterising the overall prosodic structure of speech is demonstrated
Temporal structures for Fast and Slow Speech Rate
The rhythmic component in speech synthesis often remains rather rudimentary, despite recent major efforts in the modeling of prosodic models. The European COST Action 258 has identified this problem as one of the next challenges for speech synthesis. This paper is a contribution to a new, promising approach that was tested on a French temporal model
Fast and Slow Speech Rate: a Characterisation for French
This paper is concerned with the evaluation of speech rate in French. Usually, this dynamic parameter is described as a unidimensional quantitative dimension. It is shown that the slowing down of speech has also major qualitative effects that must be taken into account. The theory on slowing down speech is thus revised
High temperature thermocouple design provides gas cooling without increasing overall size of unit
High temperature thermocouple uses a thermoelement of noncircular cross section with insulation of circular cross section to provide space for the flow of coolant gas down the probe
Silicon solar cell monitors high temperature furnace operation
Silicon solar cell, attached to each viewpoint, monitors that incandescent emission from the hot interior of a furnace without interfering with the test assembly or optical pyrometry during the test. This technique can provide continuous indication of hot spots or provide warning of excessive temperatures in cooler regions
Atmospheric degradation mechanisms of hydrogen containing chlorofluorocarbons (HCFC) and fluorocarbons (HFC)
The current knowledge of atmospheric degradation of hydrogen containing chlorofluorocarbons (HCFC 22 (CHClF2), HCFC 123 (CHCl2CF3), HCFC 124 (CHClFCF3), HCFC 141b (CFCl2CH3), HCFC 142b (CF2ClCH3)) and fluorocarbons (HFC 125 (CHF2CF3), HFC 134a (CH2FCF3), HFC 152a (CHF2CH3)) is assessed. Except for the initiation reaction by OH radicals, there are virtually no experimental data available concerning the subsequent oxidative breakdown of these molecules. However, from an analogy to the degradation mechanisms of simple alkanes, some useful guidelines as to the expected intermediates and final products can be derived. A noteable exception from this analogy, however, appears for the oxi-radicals. Here, halogen substitution induces new reaction types (C-Cl and C-C bond ruptures) which are unknown to the unsubstituted analogues and which modify the nature of the expected carbonyl products. Based on an evaluation of these processes using estimated bond strength data, the following simplified rules with regards to the chlorine content of the HCFC's may be deduced: (1) HCFC's containing one chlorine atom such as 22 and 142b seem to release their chlorine content essentially instantaneous with the initial attack on the parent by OH radicals, and for HCFC 124, such release is apparently prevented; (2) HCFC's such as 123 and 141b with two chlorine atoms are expected to release only one of these instantaneously; and the second chlorine atom may be stored in potentially long-lived carbonyl compounds such as CF3CClO or CClFO
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