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21.
Masked thresholds for a 1000-Hz sinusoidal signal were measured as a function of masker level in both forward and simultaneous masking for two types of maskers: a 1000-Hz sinusoid and a narrowband noise, 60-Hz wide, centered at 1000 Hz. In forward masking, the noise masker produced much steeper growth-of-masking functions than the sinusoid. Presenting a contralateral broadband noise "cue" with the forward masker dramatically reduced the slope of masking for the noise masker but did not influence results for the sinusoidal masker. The noise remained the more effective masker. The amount of masking produced by combinations of equally effective narrowband-noise and sinusoidal maskers was compared to that produced by each masker individually with and without the contralateral cue. No additional masking beyond that predicted by energy summation was measured for forward masking. Additional masking beyond energy-sum predictions was measured for analogous conditions in simultaneous masking. Comparisons of results obtained with and without the contralateral cue suggest that signal thresholds in the presence of narrowband-noise forward maskers can reflect nonperipheral auditory processes. 相似文献
22.
Patrizio Neff 《Mathematical Methods in the Applied Sciences》2005,28(9):1031-1060
We prove the local existence and uniqueness to a geometrically exact, observer‐invariant membrane‐plate model introduced by the author. The model consists of an elliptic partial differential system of equations describing the equilibrium response of the membrane which is non‐linearly coupled with a viscoelastic evolution equation for exact rotations, taking on the role of an orthonormal triad of directors. This coupling introduces a viscoelastic transverse shear resistance. Refined elliptic regularity results together with a new extended Korn's first inequality for plates and shells allow to proceed by a fixed point argument in appropriately chosen Sobolev‐spaces in order to prove existence and uniqueness. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
23.
Krzysztof Chełmiński Patrizio Neff Sebastian Owczarek 《Journal of Mathematical Analysis and Applications》2015
The purpose of this article is to prove the Hölder continuity up to the boundary of the displacement vector and the microrotation matrix for the quasistatic, rate-independent Armstrong–Frederick cyclic hardening plasticity model with Cosserat effects. This model is of non-monotone and non-associated type. In the case of two space dimensions we use the hole-filling technique of Widman and Morrey's Dirichlet growth theorem. 相似文献
24.
The aims of this note is to present a new model based on a new representation of the curvature energy in the indeterminate couple stress model and to discuss some related choices from the literature. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Kiefer J. Neff W.J. Lebert R. Naweed A. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1995,23(3):353-357
A radial multichannel pseudospark switch seems advantageous for switching currents exceeding 100 kA. A single common hollow cathode guarantees the same trigger conditions for all channels. The electron beams emitted out of the hollow cathode of this switch are analyzed by means of Faraday-cups by varying the circuit as well as the trigger parameters. In addition to the cup measurements, the discharge is observed using a CCD camera. It is found that each channel of the switch must receive a respective beam, before the resistance of the switch turns low, if the discharge current is to run through that channel. In addition, most of the varied parameters do not influence the electron beam 相似文献
28.
Formation of anodic iridium oxide films has been monitored using Ultraviolet Photoemission Spectroscopy (UPS) of the emersed electrodes. The potential dependent valence band spectra clearly show the onset of oxide formation at about 0.6 V versus SCE. The density of states at the Fermi level and the positron of the Fermi level with respect to the maximum of the t2g band of the oxide indicates a transition from metallic to semiconducting behaviour of the oxide. Protonation of the oxide is associated with increased emission from OH species. A linear correlation between electrode potential and workfunction change is observed for the metal as well as for the oxide. Our results confirm known band theory models and provide a fundamental understanding of the electrochromism of anodic iridium oxide films. 相似文献
29.
Lawrence Neff Stout 《manuscripta mathematica》1975,17(1):1-14
It is well known that topoi satisfy strong internal completeness and cocompleteness conditions: Lawvere [4] announced the existence of internal Kan extensions; proofs may be found in Kock and Wraith [3] and Diaconescu [2]. In this paper I give an explicit construction of the limit of an internal functor and lift the completeness and cocompleteness of ? to the category of topological space objects in ? defined by internalizing the definition in terms of open sets (as in [7] and [8]). 相似文献
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