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901.
Aging education is relatively new to the university, and our understanding of the perspectives students bring to aging populations is correspondingly limited. This investigation surveys 546 students at a midsized, Midwestern university to explore students' views toward elders, toward serving elders, and toward the relevance of aging education for various other areas of study. Our results suggest generally favorable attitudes: older students and students with greater contact with aging populations were more positive than their counterparts; gender, GPA, and aging courses taken showed sporadic or no effects on various attitudes. These preliminary findings offer a baseline for future investigations. Our findings suggest that students who have more contact through friendship and volunteer experiences have more positive attitudes toward working with older adults. Additional research is needed to examine if type of gerontological instruction is associated with attitudes toward aging and aging education.  相似文献   
902.
This study examined the relationship between hemispheric processing of complex messages and message acceptance. In particular the research sought to answer several questions regarding the processing and interpretation of persuasive messages and message sources. Based on the results of this research it was concluded that (1) the brain's right and left hemispheres, when isolated from one another, process information according to a particular “style,” (2) that semantic properties of language influence hemispheric processing, and (3) that message sources are perceived differently by the right and left hemispheres. Potential implications for the study of communication in terms of message style and acceptability, language intensity, perceptions of source, and perceptions of threat conclude this analysis.  相似文献   
903.
电子评价研究新进展   总被引:1,自引:0,他引:1  
近年来在教育技术学领域,对教育系统如何产生公平、有吸引力评价感兴趣的人,越来越清晰地认识到我们需要认真思考评价。如果我们希望创造对世界发展做出贡献的教育系统,那么我们需要思考如何通过改变评价实践来实现这个目标。本文对评价在塑造教育实践中的核心角色进行了论述,并指出了改变我们世界所面临的机遇和挑战。  相似文献   
904.
仅需为Apple手机写个小应用软件,有的孩子在自己的卧室里就能赚个百万美元。  相似文献   
905.
Dielectrophoresis (DEP), the phenomenon of directed motion of electrically polarizable particles in a nonuniform electric field, is promising for applications in biochemical separation and filtration. For colloidal particles in suspension, the relaxation of the ionic species in the shear layer gives rise to a frequency-dependent, bidirectional DEP force in the radio frequency range. However, quantification methods of the DEP force on individual particles with the pico-Newton resolution required for the development of theories and design of device applications are lacking. We report the use of optical tweezers as a force sensor and a lock-in phase-sensitive technique for analysis of the particle motion in an amplitude modulated DEP force. The coherent detection and sensing scheme yielded not only unprecedented sensitivity for DEP force measurements, but also provided a selectivity that clearly distinguishes the pure DEP force from all the other forces in the system, including electrophoresis, electro-osmosis, heat-induced convection, and Brownian forces, all of which can hamper accurate measurements through other existing methods. Using optical tweezers-based force transducers already developed in our laboratory, we have results that quantify the frequency-dependent DEP force and the crossover frequency of individual particles with this new experimental method.  相似文献   
906.
The ability to ensure the desired performance of the cooperative-antagonistic multi-agent networks (MANs) in the presence of communication constraints is an important task in many applications of real systems. In this paper, under the proposed event-triggered condition (ETC), different types of consensus are obtained under different network topology. We concentrates on the event-based bipartite consensus. It is shown that under the proposed ETC (i) the addressed cooperative-antagonistic network with arbitrary communication delays reaches bipartite consensus provided that the network is balanced; (ii) the network model reaches zero if the network is unbalanced. Further, to avoid the continuously verifying the triggering condition, a self-triggered algorithm is proposed for realizing the bipartite consensus of the network model. A numerical example is given to illustrate the effectiveness of the theoretical results.  相似文献   
907.
908.
The transition from an industrial economy to an innovation economy poses two critical questions for the manufacturing sector in advanced countries. First, given the diffusion of modern manufacturing practices around the world, what level of innovation (incremental, more far-ranging, or radical) is most likely to support a resilient domestic manufacturing sector? Second, are assumed differences in the innovative capacity across space likely to hasten the decline of rural manufacturing? To answer these questions this research combines comprehensive measures of self-reported innovation able to reliably differentiate incremental and more far-ranging innovation with establishment-level data able to examine the geographical distribution of these different innovation strategies. The data used for the analysis includes a two-period panel of manufacturing establishments surveyed in 1996 and 2013 with annual employment data indicating survival in the intervening years. Our findings suggest that long-surviving manufacturing plants overwhelmingly gravitate away from non-innovation strategies toward incremental or more far-ranging innovation orientations. A survival advantage of far-ranging innovation over incremental innovation is observed for standalone firms. We do not identify a difference in the innovation orientations of rural and urban manufacturing establishments.  相似文献   
909.
In this paper we present the modification of the Mikhailov stability criterion for linear fractional commensurate order systems. The modification consists in determining the appropriate measure for the total argument change depending on the highest fractional order αn=nα of the system and not only on the integer n as stated in the literature. The validity of the result is illustrated by means of several examples.  相似文献   
910.
This study examined the predictive ability of the medicine ball chest throw and vertical jump for muscular strength and power in adolescents. One hundred and ninety adolescents participated in this study. Participants performed trials of the medicine ball chest throw and vertical jump, with vertical jump peak power calculated via an estimation equation. One-repetition maximum and peak power for the chest press and leg press were assessed using pneumatic exercise machines. The medicine ball chest throw strongly correlated with chest press one-repetition maximum and peak power, while the vertical jump peak power strongly correlated with leg press one-repetition maximum and peak power. The predictive ability of medicine ball chest throw was better than vertical jump peak power for muscular strength and power when controlling for sex, age, height, weight, and maturation, and was not affected by involvement in sports. Results show good predictive ability of the medicine ball chest throw for muscular strength and power in adolescents, while predictable ability of vertical jump peak power is weakened when other factors are taken into account.  相似文献   
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