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991.
992.
An auditory basis for the stimulus-length effect in the perception of stops and glides 总被引:1,自引:0,他引:1
To investigate possible auditory factors in the perception of stops and glides (e.g., /b/ vs /w/), a two-category labeling performance was compared on several series of /ba/-/wa/ stimuli and on corresponding nonspeech stimulus series that modeled the first-formant trajectories and amplitude rise times of the speech items. In most respects, performance on the speech and nonspeech stimuli was closely parallel. Transition duration proved to be an effective cue for both the stop/glide distinction and the nonspeech distinction between abrupt and gradual onsets, and the category boundaries along the transition-duration dimension did not differ significantly in the two cases. When the stop/glide distinction was signaled by variation in transition duration, there was a reliable stimulus-length effect: A longer vowel shifted the category boundary toward greater transition durations. A similar effect was observed for the corresponding nonspeech stimuli. Variation in rise time had only a small effect in signaling both the stop/glide distinction and the nonspeech distinction between abrupt and gradual onsets. There was, however, one discrepancy between the speech and nonspeech performance. When the stop/glide distinction was cued by rise-time variation, there was a stimulus-length effect, but no such effect occurred for the corresponding nonspeech stimuli. On balance, the results suggest that there are significant auditory commonalities between the perception of stops and glides and the perception of acoustically analogous nonspeech stimuli. 相似文献
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Stefan Kremp 《Archiv der Mathematik》1991,57(3):273-276
Ohne Zusammenfassung 相似文献
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Petra Lommens Celso de Mello Donega Luc Piraux Stefan Mátéfi-Tempfli Zeger Hens 《Journal of luminescence》2006,118(2):245-250
We performed photoluminescence experiments on colloidal, Co2+-doped ZnO nanocrystals in order to study the electronic properties of Co2+ in a ZnO host. Room temperature measurements showed, next to the ZnO exciton and trap emission, an additional emission related to the Co2+ dopant. The spectral position and width of this emission does not depend on particle size or Co2+ concentration. At 8 K, a series of ZnO bulk phonon replicas appear on the Co2+-emission band. We conclude that Co2+ ions are strongly localized in the ZnO host, making the formation of a Co2+d-band unlikely. Magnetic measurements revealed a paramagnetic behaviour. 相似文献
999.
An overview over the binding situation in transition metal and lanthanide aminopyridinato complexes is given. True aminopyridinato complexes in which we observe a significant longer N‐amido than N‐pyridine bond length are rare and for instance observed for ruthenium. Additional examples of ruthenium aminopyridinato complexes were synthesized and characterized by X‐ray crystal structure analysis. 相似文献
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