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71.
Past research has attempted to delineate personality differences between insomniacs and good sleepers but has failed to control for type of insomnia or severity of the disorder. The purpose of this study was to compare MMPI scores of mild and severe sleep onset insomniacs with a control group of noninsomniacs. Results demonstrated that sleep onset insomniacs, regardless of degree of severity, differed significantly from noninsomniacs; and that mild and severe insomniacs differed from each other on only one MMPI scale. 相似文献
72.
Anita Williams Woolley Julia B. Bear Jin Wook Chang Arwen Hunter DeCostanza 《Organizational behavior and human decision processes》2013
We tested the effects of team strategic orientation on team member perceptions, work strategy and information search. In Experiment 1, 80 teams worked on a hidden profile decision-making task. A defensive team strategic orientation increased members’ perceptions of the problem’s scope, leading to a more process-focused work strategy and broader information search compared to an offensive team strategic orientation. When teams needed critical information from the environment, defensive teams outperformed offensive teams; offensive teams performed better when critical information resided within the team. In Experiment 2, these findings were replicated with 92 teams performing a different decision task. When making a second decision, half of the teams were led to change their strategic orientation; teams shifting from offense to defense altered their information search behavior more readily than did teams shifting in the opposite direction, suggesting an asymmetric adaptation effect. 相似文献
73.
In this study, we examine when creativity is positively or negatively related to firm performance. Building on the creation–implementation tension theorized in the literature and the attention capacity perspective, we argue that the relationship between creativity and firm performance is contingent on riskiness orientation, firm size, and realized absorptive capacity. Data were collected from 761 core knowledge employees, 148 CEOs, and 148 HR executives from 148 high‐technology firms. The results indicated that core knowledge employee creativity was negatively related to firm performance when riskiness orientation was high. The relationship was positive when realized absorptive capacity was high. Finally, the relationship was more positive in small firms than in large firms. We discuss the implications of our findings for creativity research and managerial practices. 相似文献
74.
75.
The partitioning of the trace element Sn into Cu-rich precipitates in a low-alloy pressure-vessel steel has been characterized using the three-dimensional atom probe (3DAP) technique. This investigation has revealed for the first time that the trace element Sn, present at only 0.007?at.% in the steel, partitions strongly to both small spherical precipitates (<4?nm in diameter) and to large non-spherical precipitates (largest dimension 10–50?nm) during thermal ageing. Sn was also seen to segregate strongly to the precipitate/matrix interface of a large Cu precipitate and particularly in the region where a dislocation appears to intersect the precipitate. The strong attraction of large solute atoms to special sites probably drives the interfacial segregation of Sn. This is consistent with the observation of stronger segregation of Sn to the interface of large precipitates than to the coherent interface of smaller precipitates. 相似文献
76.
C. P. Chang 《Philosophical Magazine Letters》2013,93(5):249-250
Abstract Chaki (1988) has recently proposed a model for diffusion-induced grain boundary migration (DIGM). In his Letter he concluded that the interface energy of a grain boundary and the free energy of mixing are responsible for DIGM and, from the equations he derived, it was claimed that they can explain many DIGM experimental results. However, on examining his model closely there appear to be some fundamental difficulties. The following are comments on his Letter: (1) In Chaki's calculation of ΔGs he assumed that, after interface 1 had moved a distance δx, the radius of curvature of this interface increased from R to R + δx, which gives a surface energy drop of 2γVm δx/R2. However from many DIGM observations (for example Balluffi and Cahn (1981)) the curvature of a migrating boundary is increased rather then decreased, that is, the surface free- energy term actually prevents a grain boundary from migrating rather than helping it! (2) Chaki considered ΔGcryst during the migration of interface 2. It is also necessary to consider AGcrys, during the migration of interface 1, since within the migration distance δx the structure is changed from a crystalline structure to a grain boundary core structure. ΔGm should also be considered during the migration of interface 2 since the concentration of the area swept by interface 2 will not be the same as that of a grain boundary core. 相似文献
77.
78.
Won Seok Chang Sun-Ah Song Yun Hwangbo Jae-Hyun Kim Hak-Joo Lee 《Philosophical Magazine Letters》2013,93(8):391-398
Carbon nanotubes have been intensively studied owing to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results have shown that single-walled carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the electromechanical characteristics of SWCNT networks were investigated for the application of printable strain sensors on flexible substrates. SWCNT films were formed on plastic substrates of poly(ethylene terephthalate) using a spray process. In this manner, we were able to control the transparency and obtain uniform electrical properties of the films. The films are isotropic on account of the random orientation of bundles of SWCNTs. Experimental results showed a nearly linear change in the resistance across a film when it was subjected to tensile strain, even in the inelastic range of the flexible substrate. The results demonstrate the potential use of SWCNT films for highly sensitive printable strain sensors on a macroscale. 相似文献
79.
The microstructure and crystallization behaviour of melt-spun Al88Ni9Ce2Fe1 amorphous alloy and nanophase composites have been studied by means of X-ray diffraction, transmission electron microscopy and scanning and isothermal calorimetry. The diffraction patterns from Al88Ni9Ce2Fe1 amorphous alloys are diffuse, indicating a basically amorphous structure but contain two rings presumed to be associated with quenched-in nuclei. In the cases of Al88Ni9Ce2Fe1 nanophase composites, nanoscale precipitated particles are homogeneously dispersed in an amorphous matrix, and the crystallite diameter and volume fraction are sensitive to quenching conditions. During thermal crystallization, a two-step phase transformation occurs in the amorphous alloy and nanocomposites, which is characterized by a diffusion-controlled precipitation of nanoscale Al particles and the growth of a Al3(Ni, Fe) nanophase prior to a Al11Ce3 nanophase. This study gives insight into structure-control for obtaining nanophases dispersed in an amorphous matrix by rapid quenching. 相似文献
80.
Chingching Chang 《Media Psychology》2013,16(4):415-441
A theoretical framework is proposed to test the influence of opinions of other consumers, based on perceived similarity, in two contexts. The perceived similarity of the source may be diagnostic for consumers who are concerned about mispurchase. Experiment 1, therefore, compared the effects of ads featuring a consumer versus an expert as an endorser, with participant use status as a moderator that may affect concerns about mispurchase. Potential product users rated the consumer endorser higher on perceived similarity, which increased ad credibility and resulted in better ad and brand attitudes. Experiment 2 compared the effects of information about a product delivered on a consumer blog with that of information from the advertiser's official Web site, with concern about mispurchase as a moderator. More concerned consumers rated the blogger higher than the advertiser on perceived similarity, leading to greater information credibility and more favorable attitudes toward the blog and the product. 相似文献