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61.
Smits R Warner N McQueen JM Cutler A 《The Journal of the Acoustical Society of America》2003,113(1):563-574
We present the results of a large-scale study on speech perception, assessing the number and type of perceptual hypotheses which listeners entertain about possible phoneme sequences in their language. Dutch listeners were asked to identify gated fragments of all 1179 diphones of Dutch, providing a total of 488,520 phoneme categorizations. The results manifest orderly uptake of acoustic information in the signal. Differences across phonemes in the rate at which fully correct recognition was achieved arose as a result of whether or not potential confusions could occur with other phonemes of the language (long with short vowels, affricates with their initial components, etc.). These data can be used to improve models of how acoustic-phonetic information is mapped onto the mental lexicon during speech comprehension. 相似文献
62.
Günter Schwarz Jedrzej Śniatycki Jacek Tafel 《Communications in Mathematical Physics》1997,188(2):439-448
Finite time existence and uniqueness of solutions of the evolution equations of minimally coupled Yang-Mills and Dirac systems
are proved for inhomogeneous boundary conditions. A characterization of the space of solutions of minimally coupled Yang-Mills
and Dirac equations is obtained in terms of the boundary data and the Cauchy data satisfying the constraint equation. The
proof is based on a special gauge fixing and a singular perturbation result for the existence of continuous semigroups.
Received: 18 April 1996 / Accepted: 3 March 1997 相似文献
63.
N. P. Warner 《Communications in Mathematical Physics》1990,130(1):205-215
Relationships between the modular properties of affineG characters and the modular properties of the affine characters of regular subgroups ofG are derived by considering the branching functions that appear in calculation of the index of the Dirac-Ramond operator on super-coset models. Various applications of these relationships are described, and in particular a simple algorithm is given for generating modular invariant combinations of characters of affineG at any level by using the shift vector method on suitably chosen Lorentzian, self-dual lattices.Work supported in part by funds provided by the NSF under grant No. 87-08447 and by the U.S. Department of Energy (D.O.E) under contract # DE-AC02-76ER0306, and also by a fellowship from the Alfred P. Sloan foundation 相似文献
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65.
Joykrishna Dey A. Yvette Will Rezik A. Agbaria Peter W. Rabideau Atteye H. Abdourazak Renata Sygula Isiah M. Warner 《Journal of fluorescence》1997,7(3):231-236
The spectroscopic properties of corannulene and cyclopentacorannulene are examined by use of absorption and steady-state fluorescence
measurements. A red shift in the emission maxima of cyclopentacorannulene is noted with respect to the emission maxima in
the corannulene spectrum. Similar differences in the absorption spectra of both molecules are also observed. Reasons for the
dissimilarities in the absorption and emission spectra of these molecules are discussed. The fluorescence quantum yields and
lifetimes of the molecules measured in organic solvents are reported. The fluorescence quantum yield and lifetime of cyclopentacorannulene
are lower than those of corannulene. This difference is attributed to the highly strained and nonplanar structure of cyclopentacorannulene.
The effectiveness of nitromethane as a quencher of corannulene and cyclopentacorannulene fluorescence is examined. In contrast
to previously reported results, the fluorescence of these molecules is quenched by nitromethane. Fluorescence quenching of
the molecules has been attributed to complex formation in the ground state, i.e., static quenching. 相似文献
66.
R.E. Warner R.L. Ruyle W.G. Davies G.C. Ball A.J. Ferguson J.S. Forster 《Nuclear Physics A》1975,255(1):95-108
The predictions of two fully antisymmetrized reaction theories (DWBA and PWBA-FSI) are compared with absolute coincidence cross sections for the 2H(3He, 3He p)n and 2H(3He, 3H p)p reactions exhibiting final-state interactions (FSI) and quasi-elastic scattering (QES) both with and without charge exchange. The DWBA theory takes into account both the initial 3He-d and the final N-N interactions, while the PWBA-FSI theory includes only the latter. New QES data at EHe = 35.9 MeV, as well as previously reported 26.8 and 35.9 MeV data, are fitted. The DWBA theory gives good fits, both in shape and magnitude, to spectra showing N-N final-state interactions but gives somewhat poorer fits to QES spectra whose predicted magnitudes are two to ten times too large. The PWBA-FSI theory always predicts cross sections that are too large; however the predicted shapes are about as good as those from the DWBA. The initial-state interaction is shown to affect both the width and position of QES peaks from these reactions. 相似文献
67.
Robert E. Haymond John R. Thornton Daniel D. Warner 《Annals of Operations Research》1988,14(1):305-320
A broad class of problems involving the optimal control of robot arms can be formulated as dynamic programming problems whose structure is particularly attractive for parallel processing. For certain simple cost functions the dynamic programming formulation reduces to determining the shortest path through a network. This algorithm has been implemented on a Floating Point Systems' T-20 hypercube computer. An analysis of the performance of the algorithm provides several important insights into the interplay between problem size and the number of processors in a parallel computer. The results also underscore the potential for parallel computers in real-time control applications.This work was supported in part by the Office of Naval Research, Contract N 00014-86-K-0693. 相似文献
68.
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70.
Arkady Kheyfets Norman Joseph LaFave Warner Allen Miller 《International Journal of Theoretical Physics》1988,27(2):133-158
We discuss quantum insights due to the null-strut formalism. These insights deal primarily with two topics: the formalism of a theory of canonical simplicial quantum gravity based on the geometrodynamic duality of null-strut calculus, and the natural implementation of spinors and spin networks in null-strut calculus. 相似文献