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791.
792.
Using the multiple-object tracking paradigm, this study examines how spontaneous appraisal for facial beauty affects distributed attention to multiple faces in dynamic displays. Observers tracked attractive faces more effectively than unattractive faces in this task. Tracking performance was only affected by target attractiveness, suggesting an absence of appraisal for distractor attractiveness. Attractive male faces also produced stronger binding of face identity and location for female participants. Together, the results suggest that facial attractiveness was appraised during tracking even though this was task irrelevant. Contrary to the theory that multiple-object tracking is driven by encapsulated low-level vision, our results show that the content of target representation is not only penetrable by social cognition but also modulates the course of tracking operations. 相似文献
793.
Probability is an important idea with a remarkably wide range of applications. However, psychological and instructional studies conducted in the last two decades have consistently documented poor understanding of probability among different populations across different settings. The purpose of this study is to develop a theoretical framework for describing teachers' understandings of probability. To this end, we conducted an 8-day seminar with eight high school statistics teachers in the summer of 2001. The data we collected include videotaped sessions and interviews, teachers' written work, and researchers' field notes. Our analysis of the data revealed that there was a complex mix of conceptions and understandings of probability, both within and across the teachers, which were situationally triggered, often incoherent when the teachers tried to reflect on them, and which did not support their attempts to develop coherent pedagogical strategies regarding probability and statistical inference. 相似文献
794.
Today numerous training options are available to sales organizations, and sales training teams use various means to report training effectiveness. This study utilizes Kirkpatrick’s (1959; 1960) training evaluation model and examines the interrelationships among its four levels of sales training evaluation (i.e., reactions, knowledge acquisition, behavior change, and organizational outcomes). Empirical results indicate that sales trainees’ use of training materials at work is positively related to achieving sales training outcomes, including improving (1) organizational commitment, (2) sales effectiveness, and (3) customer relations. Furthermore, trainees who had positive reactions to training were more likely to learn the material, and trainees with higher levels of knowledge retention were more likely to apply the material in the work environment. Implications are discussed that may aid sales firms to better evaluate training solutions provided by vendors and to develop more effective and accountable sales training efforts. 相似文献
795.
The micromechanical model of extrusion formation in a single crystal under stress-controlled loading in high-cycle fatigue is reviewed. In the present letter, the microstress and strain fields of a single crystal under a high-amplitude fatigue are calculated by the boundary element method. Based on Schmidt's law, the resolved shear stress to activate or to cause the continuation of slip in a slip system is taken to depend on the amount of slip in that system. The cyclic strain hardening is calculated from the experimental tensile stress-strain curve. This calculated cyclic strain hardening is compared with the experimental cyclic hardening. Good agreement is shown. 相似文献
796.
The energetic driving force and resistance for shearing and cracking in metallic glasses (MGs) are quantitatively evaluated. A universal thermodynamic criterion is proposed for better understanding the intrinsic correlations between fracture toughness and Poisson’s ratio, the competitions between various deformation modes and the ductile-to-brittle transition in MGs and other materials. A new cooperation parameter δ is also introduced to depict quantitatively the relative propensity of shearing versus cracking. This work could provide insights into the long-standing issues of deformation mechanisms of glassy materials, and be helpful in searching for ductile and tough MGs. 相似文献
797.
Gong Li Y.P. Gao Z.H. Chi J. Liu T. Zhang R.P. Liu 《Philosophical Magazine Letters》2013,93(7):543-551
A 52 m drop tube has been used to solidify bulk-glass-forming Zr41Ti14Cu12.5Ni10Be22.5 alloy. Glassy balls with different sizes solidified from the droplets whose structural features, glass-transition behaviour and crystallization kinetics have been investigated. The results indicate that the apparent activation energies of the glass transition and main crystallization reaction are significantly different from those of samples prepared by water quenching. The structural difference between the two types of glassy specimen is revealed by compression studies and in situ energy-dispersive X-ray diffraction. The results are important for understanding the structural features of bulk-forming glasses. 相似文献
798.
The effects of irradiation with electrons having energies in the range 0.7–1.7 MeV on the dark conductivity and the network of hydrogenated amorphous silicon (a-Si:H) thin films have been studied. The dark conductivity measurements show that electron irradiation leads to a degradation in the dark conductivity, with the degradation being greater at lower electron energies. The Raman results suggest that the irradiation induces structural defects in the a-Si:H films, with the lower energy electrons producing more disorder in the amorphous network. 相似文献
799.
In this study, bulk nanostructured composite Cu60Fe40 alloy is prepared by a combustion synthesis technique. The prepared Cu60Fe40 alloy consists of Cu(Fe) solid solution and Fe(Cu) solid solution phases. The large-scaled compositional segregation in the Cu-rich and Fe-rich phases is not observed, respectively. A few micron-sized dendrite (Fe(Cu) solid solution) is embedded into the nanostructured matrix (Cu(Fe) solid solution). The grain size of the matrix is in the range 50–300?nm. The yield and fracture strength of the Cu60Fe40 alloy are 540 and 1050?MPa, respectively, and the fracture strain obtained from the compression test is about 20.9%. The Cu60Fe40 alloy displays notable work hardening in the compressive deformation. 相似文献
800.
Solubility criterion for sequential disordering in metal-metal multilayers upon solid-state reaction
An n-body Ni-Ti potential is derived and applied in a molecular dynamics simulation to study the maximum supersaturated solubility of the terminal solid solutions and solid-state reaction in a Ni/Ti bilayer. It reveals that during interfacial reaction of the Ni/Ti bilayer the Ti lattice reaches its maximum solubility by dissolving Ni earlier than Ni does through dissolution of Ti, which results in a sequential disordering of first Ti and then Ni, although Ti has a higher melting point than Ni. In the Ni-Zr, Ni-Mo and Ni-Ta systems, however, the Ni lattice collapses more rapidly because it reaches a maximum solubility earlier than its partners, which have higher melting points than Ni. A solubility criterion is thus relevant for all the above cases; the lower the maximum solid solubility the less stable is the lattice of the metal upon solid-state reaction. 相似文献