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21.
Examined the achieving styles, coping strategies, gender roles, and feminist attitudes of 125 prominent, highly achieving Black and White women (mean age 53.5 yrs) in the US. Multivariate analyses of variance were used to examine race differences and similarities; canonical regression analyses (MANOVAs) were used to examine relationships among achieving styles and the other sets of variables. Both similarities and differences between Black and White women were found, and achieving styles were significantly related to the other variables. Strengths, limitations, and implications of the study for counseling are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Using TAT data collected prior to entering management positions, sex differences in motive patterns related to leadership were examined in a 12-yr longitudinal study of 211 men and 180 women (aged 21–43 yrs at initial assessment) who entered a large utility corporation between 1977 and 1982. Ss were followed up in 1990 and recorded as to how far they had advanced in management level. While the results showed no sex differences in motivational predictors of attained management level, the content analysis revealed 2 distinct styles of power-related themes that distinguished the successful men from the successful women. The successful male managers were more likely to use reactive power themes while the successful female managers were more likely to use resourceful power themes. Differences between the sexes in the power themes were less pronounced among the managers who had remained in lower levels of management. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Johnson-Laird P. N.; Byrne Ruth M. J.; Schaeken Walter 《Canadian Metallurgical Quarterly》1994,101(4):734
D. P. O'Brien et al (see record 1995-08272-001) argue that the mental model theory of propositional reasoning is easy to refute, and they report 3 experiments that they believe falsify the theory. In contrast, L. Bonatti (see record 1995-08253-001) argues that the model theory is too flexible to be falsified. It is shown that the experiments by O'Brien et al do not refute the model theory and that Bonatti's claims are ill founded. Formal rule theories of propositional reasoning have 3 major weaknesses in comparison with the model theory: (1) They have no decision procedure; (2) they lack predictive power, providing no account of several robust phenomena (e.g., erroneous conclusions tend to be consistent with the premises); and (3) as a class of theories, they are difficult to refute experimentally. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Ray P. S. Han Kai-Yuan Yeh Guoli Liu Diankui Liu 《International Journal of Engineering Science》1992,30(12):1773-1787
The scattering and diffraction of plane SH-waves, by an arbitrary-shaped cylindrical canyon in anisotropic media is formulated here. Analytical solutions are obtained via the complex function theory, using the orthogonal property of the Hermite functions to solve the resulting set of infinite algebraic equations. Expressions for scattered displacements and scattered stresses are given. Three cross-sectional profile types are used in the numerical simulation of the two-dimensional canyon topography: (a) a semi-circular profile, (b) a semi-elliptical profile and (c) a triangular profile. The results obtained in (a) and (b) are consistent with known solutions computed by Trifunac and his co-workers [1,3] using a different method. As the exact solution for (c) is not known to exist, the result given here is believed to be new and would therefore serve as a useful check for numerical analysts working in this area. 相似文献
25.
Indexed in current contents 相似文献
26.
Yu-Li Hsueh Jaedon Kim Ching-Fong Su Rabbat R. Hamada T. Tian C. Kazovsky L.G. 《Lightwave Technology, Journal of》2006,24(1):44-53
A sublambda traffic-grooming scheme on wavelength-division-multiplexed (WDM) rings, which is called optical burst transport (OBT), is proposed. The network protocol and architecture allow increased flexibility to tailor the transport network behavior for efficient delivery of bursty data traffic. Using different network parameters, its performance is analyzed via simulation, and the implementation issues including the media-access-control (MAC) protocol, tunable-filter controller, and burst-mode receiver are addressed. Finally, the feasibility of the OBT with an experimental testbed built by the authors is demonstrated and a streaming-video application is used to present its overall functionality. 相似文献
27.
Multiple forms of a symbol-digit substitution task were used to provide a componential analysis of age differences in coding task performance. The results demonstrated age differences in feature encoding, memory, and visual search. A 2nd experiment was conducted with young adults to investigate a sensory deficit as a locus of age differences. The spatial contrast sensitivity deficit of older adults was simulated on forms by applying a digital filter. Persons in the age-simulated contrast condition performed worse than those in the normal contrast condition. The stimulus degradation effect was linked to visual search speed. The study illustrates the utility of componential analysis and offers direct support for the hypothesis that sensory deficits affect performance on tasks used to assess intelligence (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
The effectiveness of overlearning in enhancing performance has been acknowledged by researchers within the training community for years. In spite of this general consensus, the empirical basis for this claim is often not clear. This article presents a meta-analysis of the effects of overlearning on retention. Results indicate that overlearning produces a significant effect on retention of moderate overall magnitude and that the effect of overlearning on retention is moderated by the degree of overlearning, type of task, and length of retention period. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
The solubilities of ethyl palmitate, ethyl oleate, ethyl eicosapentaenoate (EPA) and ethyl docosahexaenoate (DHA) in supercritical
carbon dioxide were determined by a continuous flow method. The solubilities of fatty acid ethyl esters increased with pressure
and decreased as the temperature was increased. An empirical equation, similar to Chrastil's equation, was used to describe
the relationship between solute solubility and the density of carbon dioxide. The empirical equation was further used to qualitatively
estimate the separation efficiency of isolating EPA and DHA ethyl esters from fatty acid esters. The operating conditions
yielding high solubility gave fast extraction rate but resulted in low separation efficiency. Experiments were conducted to
separate ethyl EPA and ethyl DHA from a model mixture containing four fatty acid ethyl esters and from esterified squid visceral
oil. The experimental data compared closely with the calculated values. 相似文献
30.
Organic‐acid‐catalyzed sol–gel route for preparing poly(methyl methacrylate)–silica hybrid materials
Jui‐Ming Yeh Kuan‐Yeh Huang Chung‐Feng Dai B. G. Chand Chang‐Jian Weng 《应用聚合物科学杂志》2008,110(4):2108-2114
In this study, a series of organic–inorganic hybrid sol–gel materials consisting of a poly(methyl methacrylate) (PMMA) matrix and dispersed silica (SiO2) particles were successfully prepared through an organic‐acid‐catalyzed sol–gel route with N‐methyl‐2‐pyrrolidone as the mixing solvent. The as‐synthesized PMMA–SiO2 nanocomposites were subsequently characterized with Fourier transform infrared spectroscopy and transmission electron microscopy. The solid phase of organic camphor sulfonic acid was employed to catalyze the hydrolysis and condensation (i.e., sol–gel reactions) of tetraethyl orthosilicate in the PMMA matrix. The formation of the hybrid membranes was beneficial for the physical properties at low SiO2 loadings, especially for enhanced mechanical strength and gas barrier properties, in comparison with the neat PMMA. The effects of material composition on the thermal stability, thermal conductivity, mechanical strength, molecular permeability, optical clarity, and surface morphology of the as‐prepared hybrid PMMA–SiO2 nanocomposites in the form of membranes were investigated with thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, gas permeability analysis, ultraviolet–visible transmission spectroscopy, and atomic force microscopy, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献