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81.
D Kahn L R Rabiner A E Rosenberg 《The Journal of the Acoustical Society of America》1984,75(2):590-598
In a recently proposed approach to isolated-word recognition, word reference templates are constructed from a universal set of demisyllable units by concatenating the appropriate demisyllables for each vocabulary item. A dynamic time warping (DTW) algorithm is used to align test and reference patterns optimally. Nevertheless some sort of syllable duration preadjustment is necessary because of the large potential difference in duration between isolated and in-context syllables. We have found that a simple rule that reduces the length of rhyme (final) demisyllables in nonword-final stressed syllables to approximately half their isolated-syllable duration provides recognition accuracy as high as that attained through use of complex, highly context-sensitive rules. In addition to its practical application, this result can be regarded as a further demonstration of the power of DTW. We have also investigated the requirements for parameter smoothing at demisyllable boundaries. We find that an optimal window duration for smoothing is about 60-90 ms, but that failure to smooth reduces recognition accuracy only about 2% in an 1109 word test set; that linear and parabolic smoothing are equally effective; and that it does not appear that recognition accuracy can be improved by smoothing in certain phonetic contexts only. Taken together, these results can be viewed as confirming the suitability of the demisyllable as the basic unit in recognition systems. 相似文献
82.
83.
I. G. Rosenberg 《Algebra Universalis》1978,8(1):221-227
A simple characterization of the subalgebra systems of direct powers of finitary universal algebras on a fixed infinite setA is given. For |I|≥|A| such subalgebra system of anI-power is precisely an algebraic closure systemS onA
I
closed under mutations ofI (which encompass both the precomposition by permutations ofI and allowing the values at specified elements ofI to become unrestricted) and such that each function in the intersection ofS is constant. For |I|<|A| the subalgebra systems ofI-powers are obtained as the restrictions toI of such closure systems on someA
J
withJ⊇I and |J|=|A|.
Presented by J. D. Monk. 相似文献
84.
R C Rosenberg S Wherland R A Holwerda H B Gray 《Journal of the American Chemical Society》1976,98(20):6364-6369
85.
86.
M.G. White R.A. Rosenberg S.-T. Lee D.A. Shirley 《Journal of Electron Spectroscopy and Related Phenomena》1979,17(5):323-344
The He(I) photoelectron spectra of the Group IV—VI diatomics GeO, GeS, GeSe, GeTe, SnS, SnSe, and SnTe are presented. The outermost valence structure of these molecules is similar to that observed in the lighter series CO, CS, etc. of this valence isoelectronic group; in each case a relatively sharp peak is assigned to ionization from the nominally non-bonding 3σ orbital and a broader band to ionization from the bonding 1π orbital. At higher binding energies the spectra exhibit several peaks where only a single peak is expected, from the (2σ)?1 hole state. This structure is assigned to correlation peaks resulting from configuration interaction among hole states of 2Σ+ (Ω = ) symmetry. Semi-empirical CNDO—MO calculations have been performed for these molecules, and the results are used to interpret the observed trends. In addition, a simple molecular orbital model is employed to estimate the importance of spin—orbit coupling in the valence electronic structure of the heavy IV—VI ions. 相似文献
87.
Boris Botvinnik Jonathan Rosenberg 《Proceedings of the American Mathematical Society》2005,133(2):545-556
The statement often called the Gromov-Lawson-Rosenberg Conjecture asserts that a manifold with finite fundamental group should admit a metric of positive scalar curvature except when the -valued index of some Dirac operator with coefficients in a flat bundle is non-zero. We prove spin and oriented non-spin versions of this statement for manifolds (of dimension ) with elementary abelian fundamental groups , except for ``toral' classes, and thus our results are automatically applicable once the dimension of the manifold exceeds the rank of . The proofs involve the detailed structure of , as computed by Johnson and Wilson.
88.
Abstract -The semiconduction and photoconduction currents through 1-ml thick sandwich cells of all-trans-, 13- cis- , 11- cis -retinal-, and 13- cis -retinal-m-nitroaniline-hydrogen chloride were measured as a function of the temperature in both the crystalline and melted states. From the slopes of graphs of the log of the current against 1000/TGK, the activation energies for semiconduction and photoconduction were calculated using the conductivity equations for the band model. The results of the average semiconduction activation energy measurements fell into two categories: The first group has activation energies between 1.9 and 2.4 eV and includes crystalline all- trans- , 13- cis -,9 cis -retinal, and both crystalline and melted 13- cis -retinal- m -nitroanaline hydrogen chloride; the second group has activation energies between 3.1 and 3.6 eV and includes crystalline 11- cis -retinal samples shorted. The average photoconduction activation energy for crysalline 13- cis - and 11- cis -retinal, being 0.25 and 0.24 eV respectively, were essentially identical within experimental error, whereas the same parameter for 13- cis -retinal- m -nitroaniline hydrogen chloride was considerably lower at 0.15 eV. All- trans -retinal was not measurably photoconductive and 9- cis -retinal was only slightly photoconductive. 相似文献
89.
The method of pseudo-Boolean programming (given in [5], [7] and briefly described in § 2 of this paper) is used for the systematic determination of the chromatic number, of the number of internal stability, of the number of external stability and of the kernels of a finite graph. 相似文献
90.
This paper presents a new method to implement Taylor series in floating point arithmetic to generate trigonometric functions. With this method the number of terms that need to be computed is determined a priori from the exponent in the floating point representation of the argument, thereby minimizing execution time while maintaining a specified level of significance. 相似文献