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Three experiments tested listeners' ability to identify 70 diverse environmental sounds using limited spectral information. Experiment 1 employed low- and high-pass filtered sounds with filter cutoffs ranging from 300 to 8000 Hz. Listeners were quite good (>50% correct) at identifying the sounds even when severely filtered; for the high-pass filters, performance was never below 70%. Experiment 2 used octave-wide bandpass filtered sounds with center frequencies from 212 to 6788 Hz and found that performance with the higher bandpass filters was from 70%-80% correct, whereas with the lower filters listeners achieved 30%-50% correct. To examine the contribution of temporal factors, in experiment 3 vocoder methods were used to create event-modulated noises (EMN) which had extremely limited spectral information. About half of the 70 EMN were identifiable on the basis of the temporal patterning. Multiple regression analysis suggested that some acoustic features listeners may use to identify EMN include envelope shape, periodicity, and the consistency of temporal changes across frequency channels. Identification performance with high- and low-pass filtered environmental sounds varied in a manner similar to that of speech sounds, except that there seemed to be somewhat more information in the higher frequencies for the environmental sounds used in this experiment. 相似文献
6.
Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献
7.
Study of magnetoresistance and conductance of bicrystal grain boundary in La0.67Ba0.33MnO3 thin film
La0.67Ba0.33MnO3 (LBMO) thin film is deposited on a 36.7°C SrTiO3 bicrystal substrate using laser ablation technique. A microbridge is created across bicrystal grain boundary and its characteristics
are compared with a microbridge on the LBMO film having no grain boundary. Presence of grain boundary exhibits substantial
magnetoresistance ratio (MRR) in the low field and low temperature region. Bicrystal grain boundary contribution in MRR disappears
at temperature T>175 K. At low temperature, I-V characteristic of the microbridge across bicrystal grain boundary is nonlinear. Analysis of temperature dependence of dynamic
conductance-voltage characteristics of the bicrystal grain boundary indicates that at low temperatures (T<175 K) carrier transport across the grain boundary in LBMO film is dominated by inelastic tunneling via pairs of manganese
atoms and tunneling through disordered oxides. At higher temperatures (T>175 K), magnetic scattering process is dominating. Decrease of bicrystal grain boundary contribution in magnetoresistance
with the increase in temperature is due to enhanced spin-flip scattering process. 相似文献
8.
Marc Potterat et Rudolf Gygi 《Fresenius' Journal of Analytical Chemistry》1966,221(1):312-320
Résumé Un procédé de distillation est décrit qui permet d'extraire des eaux-de-vie les substances aromatiques peu volatiles, entraînables à la vapeur d'eau et insolubles dans l'eau. L'analyse par C.P.G. de la fraction aromatique a montré qu'elle était composée d'un très grand nombre de substances. Il semble que ces aromagrammes puissent servir à l'identification d'eauxde-vie ou à la recherche de falsifications (eau-de-vie artificielle).
Summary A report is given on the isolation of almost pure essential oils from spirits by a special distillation procedure. The fully automated apparatus is described in detail. The very complicated composition of the essential oils obtained has been shown by gas-chromatographic analysis (up to 250 different substances). As the composition appeared to be specific for given kinds of spirits it is hoped that the aromagrams obtained by gas chromatography may prove to be useful for the identification of spirits and for the detection of adulterations.相似文献
9.
Molar extinction coefficients of some carbohydrates viz. l-arabinose (C5H10O5), d-glucose (C6H12O6), d-mannose (C6H12O6), d-galactose (C6H12O6), d(-) fructose (C6H12O6) and maltose (C12H24O12) in aqueous solutions have been determined at 81, 356, 511, 662, 1173 and 1332 keV by gamma ray transmission method in a
narrow beam good geometry set-up. These coefficients have been found to depend upon the photon energy following a 4-parameter
polynomial. These extinction coefficients for different sugars having the same molecular formula have same values varying
within experimental uncertainty. Within concentration ranges studied, Beer-Lambert law is obeyed very well. 相似文献
10.
Hans Gygi 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1958,9(5-6):26-30
Ohne Zusammenfassung
Escher Wyss AG. 相似文献