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91.
Three experiments using computer-generated human figures showed that after a prolonged observation of eyes looking to the left (or right), eyes looking directly toward the viewer appeared directed to the right (or left). Observation of an arrow pointing left or right did not induce this aftereffect on the perceived eye direction. Happy faces produced the aftereffect more effectively than surprised faces, even though the image features of the eyes were identical for both the happy and the surprised faces. These results suggest that the eye direction aftereffect may reflect the adaptation of relatively higher-level mechanisms analyzing the others eye direction. 相似文献
92.
A statistical manifold Mμ consists of positive functions f such that defines a probability measure. In order to define an atlas on the manifold, it is viewed as an affine space associated with a subspace of the Orlicz space LΦ. This leads to a functional equation whose solution, after imposing the linearity constrain in line with the vector space assumption, gives rise to a general form of mappings between the affine probability manifold and the vector (Orlicz) space. These results generalize the exponential statistical manifold and clarify some foundational issues in non-parametric information geometry. 相似文献
93.
Understanding the object benefit in visual short-term memory: the roles of feature proximity and connectedness 总被引:2,自引:0,他引:2
Xu Y 《Perception & psychophysics》2006,68(5):815-828
Past research has identified visual objects as the units of information processing in visual short-term memory (VSTM) and has shown that two features from the same object can be remembered in VSTM as well (or almost as well) as one feature of that object and are much better remembered than the same two features from two spatially separated objects. It is not clear, however, what drives this object benefit in VSTM. Is it the shared spatial location (proximity), the connectedness among features of an object, or both? In six change detection experiments, both location/proximity and connectedness were found to be crucial in determining the magnitude of the object benefit in VSTM. Together, these results indicate that location/proximity and connectedness are essential elements in defining a coherent visual object representation in VSTM. 相似文献
94.
Preschoolers' theory-of-mind development follows a similar age trajectory across many cultures. To determine whether these similarities are related to similar underlying ontogenetic processes, we examined whether the relation between theory of mind and executive function commonly found among U.S. preschoolers is also present among Chinese preschoolers. Preschoolers from Beijing, China (N= 109), were administered theory-of-mind and executive-functioning tasks, and their performance was compared with that of a previously studied sample of U.S. preschoolers (N= 107). The Chinese preschoolers outperformed their U.S. counterparts on all measures of executive functioning, but were not similarly advanced in theory-of-mind reasoning. Nonetheless, individual differences in executive functioning predicted theory of mind for children in both cultures. Thus, the relation between executive functioning and theory of mind is robust across two disparate cultures. These findings shed light on why executive functioning is important for theory-of-mind development. 相似文献
95.
Kaoru Tomita Jun Yamada Shigenobu Takatsuka 《Journal of psycholinguistic research》2010,39(5):375-391
This study investigated how Japanese-speaking learners of English pronounce the three point vowels /i/, /u/, and /a/ appearing
in the first and second monosyllabic words of English noun phrases, and the schwa /ə/ appearing in English disyllabic words.
First and second formant (F1 and F2) values were measured for four Japanese speakers and two American English speakers. The
hypothesis that the area encompassed by the point vowels in the F1-F2 vowel space tends to be smaller for the Japanese speakers
than for the English speakers was verified. The hypothesis that the area formed by the three schwas in chicken{{chick\underline{e}n}}, spoonful{{spoonf{\underline{u}}l}}, and Tarzan{{Tarz\underline{a}n}} is greater for the Japanese speakers than for the English speakers and its related hypothesis were largely upheld. Implications
for further research are briefly discussed. 相似文献
96.
Discontinuous precipitation in a two-phase Zn-rich Zn-6.3at.%Ag alloy has been studied. It has been shown that the eta/epsilon interphase boundaries have the ability to initiate discontinuous precipitation as do the eta/eta grain boundaries. The back-polishing method is used to show the interconnection between a discontinuous precipitate colony and the eta/epsilon interphase boundary. The reaction front velocity of discontinuous precipitation initiated at the eta/eta grain boundary is 12-90% higher than that of discontinuous precipitation initiated at the eta/epsilon interphase boundary under various ageing temperatures. 相似文献
97.
We present an analysis and results on the homogeneous nucleation of a dislocation loop under stress in a perfect crystal. By using a variational boundary integral method in the Peierls-Nabarro framework, we have determined the saddle-point configurations of embryonic dislocation loops and their associated activation energies under stress levels up to the ideal shear strength. The high-energy barriers under the usual levels of applied shear stresses, differing markedly from the ideal shear strength, confirm the widely held view that thermal motion should play no role in such nucleation. The result provides means for more definitive solutions of fundamental problems involving homogeneous nucleation of dislocation loops and has significant implications for models based on the mechanism of nucleation of dislocations from a perfect crystal. 相似文献
98.
Hao Chen Wei Xu Mohamed Goune Sybrand van der Zwaag 《Philosophical Magazine Letters》2013,93(10):547-555
The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning. 相似文献
99.
Four-phonon model of soft-matter quasicrystals is proposed, in which there are three solid phonons and one fluid phonon. With this model, the vibration spectrum of soft-matter quasicrystals can be obtained. The generalized Debye frequency, generalized Debye temperature and the thermodynamic functions of soft-matter quasicrystals are observed. The results on the specific heat of soft-matter quasicrystals demonstrate the contributions of both solid phonons and fluid phonon, respectively. 相似文献
100.
The mechanical softening behaviour of micrometre-scale metals (free-standing metal foils and wires) with decreasing either the geometrical or the microstructural scale (i.e. the smaller, the weaker) has recently been reported. Here, we present a mechanism-based model to understand the softening behaviour, which is based on competition between the effects of surface grain relaxation and the interior grain strengthening effect. The model describes well the yield stress of Cu foils with different ratios of the thickness to grain size. 相似文献