排序方式: 共有26条查询结果,搜索用时 15 毫秒
11.
The purpose of this study was to determine the accuracy with which listeners could identify the gender of a speaker from a synthesized isolated vowel based on the natural production of that speaker when (1) the fundamental frequency was consistent with the speaker's gender, (2) the fundamental frequency was inconsistent with the the speaker's gender, and (3) the speaker was transgendered. Ten male-to-female transgendered persons, 10 men and 10 women, served as subjects. Each speaker produced the vowels /i/, /u/, and //. These vowels were analyzed for fundamental frequency and the first three formant frequencies and bandwidths. Formant frequency and bandwidth information was used to synthesize two vowel tokens for each speaker, one at a fundamental frequency of 120 Hz and one at 240 Hz. Listeners were asked to listen to these tokens and determine whether the original speaker was male or female. Listeners were not aware of the use of transgendered speakers. Results showed that, in all cases, gender identifications were based on fundamental frequency, even when fundamental frequency and formant frequency information was contradictory. 相似文献
12.
We go back and forth between, on the one hand, presentations of arithmetic and Kac-Moody groups and, on the other hand, presentations of profinite groups, deducing along the way new results on both. 相似文献
13.
M. Y. Gelfer A. Waddon K. Schmidt‐Rohr R. Gale L. Kleiner R. Berggren 《Journal of Polymer Science.Polymer Physics》2001,39(22):2774-2780
The 50% increased permeability after annealing of semicrystalline poly(ethylene/vinylacetate) containing 3 mol % vinylacetate is linked to increased mobility in the amorphous phase, as identified by line‐narrowing of 1H wideline nuclear magnetic resonance (NMR) spectra and by reduced cross‐polarization efficiency in 13C NMR. Other morphological parameters, such as crystallinity, measured as 30 to 35% by differential scanning calorimetry (DSC) and NMR, are hardly changed by annealing. Small‐angle X‐ray scattering and NMR studies, using spin diffusion as well as T1ρ and T1 relaxation, detected only a small increase in crystallite thickness. The annealing‐induced enhancement in segmental mobility in the amorphous regions corresponds to a temperature shift of about 10 K, from which an increase of the motional rate by a factor of 2 is estimated, and which can account for the enhancement in the permeability. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2774–2780, 2001 相似文献
14.
SUMMARY: The purpose of this study was to compare maximum prolongations of controlled-intensity /s/ vs. /z/ in young healthy male and female adults and to compare the s/z ratio in young men and women. Twenty young adult men and 20 young adult women were included in this study. Participants produced 10 trials of /s/ and 10 of /z/ with a controlled intensity of 60-dB sound-pressure level (SPL). Maximum prolongations and s/z ratio were determined by three different methods: based on the longest out of 10 trials, the longest of 3 trials, and an average of the first 3 trials. Results revealed that based on averaged group data, /s/ and /z/ seemed to be prolonged for similar durations. Men consistently prolonged both phonemes significantly longer than women. There were no significant differences in s/z ratio between men and women. However, when individual data were reviewed, it seemed that some subjects consistently prolonged /s/ for a longer duration than /z/, some subjects prolonged /z/ longer than /s/, and some subjects actually produced approximately equal durations of the two phonemes. It was further noted that /s/ durations were more favorably impacted by practice than /z/ durations. 相似文献
15.
M. Y. Gelfer Hyun H. Song Lizhi Liu Benjamin S. Hsiao Benjamin Chu Miriam Rafailovich Mayu Si Vladimir Zaitsev 《Journal of Polymer Science.Polymer Physics》2003,41(1):44-54
Morphology, thermal and rheological properties of polymer‐organoclay composites prepared by melt‐blending of polystyrene (PS), poly(methyl methacrylate) (PMMA), and PS/PMMA blends with Cloisite® organoclays were examined by transmission electron microscopy, small‐angle X‐ray scattering, secondary ion mass spectroscopy, differential scanning calorimetry, and rheological techniques. Organoclay particles were finely dispersed and predominantly delaminated in PMMA‐clay composites, whereas organoclays formed micrometer‐sized aggregates in PS‐clay composites. In PS/PMMA blends, the majority of clay particles was concentrated in the PMMA phase and in the interfacial region between PS and PMMA. Although incompatible PS/PMMA blends remained phase‐separated after being melt‐blended with organoclays, the addition of organoclays resulted in a drastic reduction in the average microdomain sizes (from 1–1.5 μm to ca. 300–500 nm), indicating that organoclays partially compatibilized the immiscible PS/PMMA blends. The effect of surfactant (di‐methyl di‐octadecyl‐ammonia chloride), used in the preparation of organoclays, on the PS/PMMA miscibility was also investigated. The free surfactant was more compatible with PMMA than with PS; the surfactant was concentrated in PMMA and in the interfacial region of the blends. The microdomain size reduction resulting from the addition of organoclays was definitely more significant than that caused by adding the same amount of free surfactant without clay. The effect of organoclays on the rheological properties was insignificant in all tested systems, suggesting weak interactions between the clay particles and the polymer matrix. In the PS system, PMMA, and organoclay the extent of clay exfoliation and the resultant properties are controlled by the compatibility between the polymer matrix and the surfactant rather than by interactions between the polymer and the clay surface. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 44–54, 2003 相似文献
16.
It has been shown that boost modes of two-dimensional fermions on a light cone are expressed in terms of the Dirac delta function of a complex argument. Therefore, the decomposition of integrals over the entire range of the boost parameter into parts is inapplicable and the Unruh quantization is valid only in the double Rindler wedge, rather than in the entire Minkowski space. This means that the Unruh “effect” is absent for any statistics of particles. Thus, both the theoretical predictions and numerous proposals of experiments based on the assumption of the existence of this effect are unfounded. 相似文献
17.
18.
Nawani P Gelfer MY Hsiao BS Frenkel A Gilman JW Khalid S 《Langmuir : the ACS journal of surfaces and colloids》2007,23(19):9808-9815
A unique class of nanoclays was prepared by modification of pristine clays or organoclays (Cloisite C20A) with transition metal ions (TMIs). The composition, structure, morphology and thermal properties of TMI-modified nanoclays were investigated by atomic absorption spectroscopy (AAS), elemental analysis (EA), scanning electron microscopy (SEM), small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray absorption near-edge structure (XANES) spectroscopy. The content of TMIs in modified clays was found to be close to the limiting value of ion exchange capacity. SEM and X-ray results confirmed that TMIs were located between the mineral layers instead of being adsorbed on the surface of clay particles. TGA results indicated that the TMI treatment of organoclays could significantly increase the thermal stability, which was more pronounced in air than in nitrogen. Temperature-resolved SAXS measurements revealed that the presence of TMIs increased the onset temperature of structural degradation. The higher thermal stability of TMI-modified organoclays can be attributed to the change in the thermal degradation mechanism, resulting in a decrease in the yield of volatile products and the formation of char facilitated by the presence of catalytically active TMIs. 相似文献
19.
20.
Geometric and dynamic properties of embeddings of SL(2; ℤ) into the Cremona group are studied. Infinitely many nonconjugate
embeddings that preserve the type (i.e., that send elliptic, parabolic and hyperbolic elements onto elements of the same type)
are provided. The existence of infinitely many nonconjugate elliptic, parabolic and hyperbolic embeddings is also shown. In
particular, a group G of automorphisms of a smooth surface S obtained by blowing up 10 points of the complex projective plane is given. The group G is isomorphic to SL(2; ℤ), preserves an elliptic curve and all its elements of infinite order are hyperbolic. 相似文献