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1.
Yoon Carolyn; Feinberg Fred; Hu Ping; Gutchess Angela Hall; Hedden Trey; Chen Hiu-Ying Mary; Jing Qicheng; Cui Yao; Park Denise C. 《Canadian Metallurgical Quarterly》2004,19(3):379
Understanding how aging influences cognition across different cultures has been hindered by a lack of standardized, cross-referenced verbal stimuli. This study introduces a database of such item-level stimuli for both younger and older adults, in China and the United States, and makes 3 distinct contributions. First, the authors specify which item categories generalize across age and/or cultural groups, rigorously quantifying differences among them. Second, they introduce novel, powerful methods to measure between-group differences in freely generated ranked data, the rank-ordered logit model and Hellinger Affinity. Finally, a broad archive of tested, cross-linguistic stimuli is now freely available to researchers: data, similarity measures, and all stimulus materials for 105 categories and 4 culture-by-age groups, comprising over 10,000 fully translated unique item responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The relationship between teachers' judgments versus actual performance on curriculum-based measures in reading was examined. A total of 30 regular education teachers were asked to predict the oral reading fluency score of students along with a rating scale of reading subskills. Correlations between teacher judgment measures and student performance found that teachers were accurate reporters of student performance levels in reading. However, some questions were raised whether teachers were accurate at predicting the actual level of student oral reading fluency when effect sizes were used to compare teacher judgment and actual student performance. Recommendations for continued research in understanding the parameters of the accuracy of teacher judgment are made. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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We describe a simple, optical technique for mapping 180° domains hidden inside photorefractive crystals. We intersect two coherent light beams in the crystal. Photorefractive coupling between the two beams causes one beam to emerge with a map of all the crystal's 180° domains imprinted upon it. We tested many BaTiO(3) crystals and found that they all contained 180° domains, with the relative volume of these domains varying from 25% to 0.1%. 相似文献
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Frederick Wieland Lawrence Hawley Abe Feinberg Mike Di Loreto Leo Blume Joseph Ruffles Peter Reiher Brian Beckman Philip Hontalas Steven Bellenot David Jefferson 《Concurrency and Computation》1989,1(1):35-50
This paper analyzes the performance of a discrete-event combat simulation executed on a parallel processor under control of the Time Warp Operating System. Time Warp is in a class of distributed simulation methods called Optimistic methods which have proven to be useful over a wide range of simulations. The combat simulation used for this performance study, called STB88, is a division-corps model incorporating a number of different types of computations. The speed-up for three versions of this model on the Caltech/JPL Mark III Hypercube and the BBN Butterfly parallel processors was measured relative to an efficient sequential execution of the same model on the same hardware. The results indicate that STB88 version 1 achieves a speed-up of 28.6 on 60 Mark III processors, while STB88 version 2 achieves a speed-up of 36.8 on 100 Butterfly processors. Version 3 of STB88 achieved a speed-up of 38.5 on 128 Mark III processors. The versions differed only in their interface to Time Warp. On the Butterfly, the sequential execution completed in 2 hours, while the 100 processor execution completed in 3.2 minutes. 相似文献
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Deparis O. Kiyan R. Salik E. Starodubov D. Feinberg J. Pottiez O. Megret P. Blondel M. 《Photonics Technology Letters, IEEE》1999,11(10):1238-1240
Round-trip time and intracavity dispersion were optimized in a dual-wavelength actively mode-locked Er-doped fiber laser including two nonchirped fiber Bragg gratings. This optimization allowed to generate nearly transform-limited pulses as short as 16 and 13 ps at 1547 and 1562 nm, respectively, at a 3-GHz repetition rate only limited by the modulator bandwidth. In the experiment, the round-trip time difference between pulses at two wavelengths was adjusted using a fiber stretcher. Intracavity dispersion was managed at each wavelength separately 相似文献
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This study investigates the composition of customer relationship management (CRM) in e-business by examining the possible elements that determine different aspects of the relationship between customers and e-businesses. A web-based CRM survey of 38 items, constructed from SERVQUAL (service quality instrument), SITEQUAL (website service quality instrument) and literature findings, was completed by 200 customer contact professionals. Results of a factor analysis indicated three main customer relationship attributes of e-business, which are: general CRM (accounting for 51% of the total variance); personalization (accounting for 9% of the total variance); and privacy (accounting for 7% of the total variance). Results of a stepwise regression indicated that these customer relationship attributes significantly predict customer attitude (83% of the explained variance). Within the general CRM dimension, website content organization correlated highly with customer attitude (65% of the explained variance). The results of the study indicate that customers perceive three main dimensions of relationship attributes of e-business (general CRM, personalization and privacy) and that all three significantly contribute to customer attitude. These findings support the importance of including relational-type e-business attributes when investigating interactions between customers and e-business. The study concludes with related implications and design guidelines to enhancing customer perception of e-business. 相似文献