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31.
32.
Through two experiments, the study sought to emphasize the usefulness of the visual and kinesthetic imagery in mental practice. In Experiment 1, it was hypothesized that when the task to be learned through mental practice necessitates the reproduction of a form by drawing, the visual image, which provides a wide span of apprehension, is more suitable than the kinesthetic image. On the other hand, the kinesthetic image that supplies inputs from the muscles' positions and movements should be more appropriate for the acquisition of the duration of the drawing. In Experiment 2, it was hypothesized that the task, transformed into a motor task necessitating minute coordination of the two hands, would benefit more from kinesthetic imagery. To have optimal control over what was actually experienced during mental practice, the participants' imagery skills were measured. The participants also benefited from prior imagery training. The results demonstrate that when using mental practice to initially acquire a task, visual imagery is better for tasks that emphasize form while kinesthetic imagery is better for those tasks that emphasize timing or minute coordination of the two hands. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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34.
J. W. Huang J. M. Ryan K. L. Bray T. F. Kuech 《Journal of Electronic Materials》1995,24(11):1539-1546
The defect engineering in metalorganic vapor phase epitaxy InxGa1-xAs and InP by controlled oxygen doping using diethyl aluminum ethoxide (DEALO) was developed in this study. DEALO doping has
led to the incorporation of Al and O, and the compensation of shallow Si donors in InxGa1−xAs: Si with 0 ≤ x ≤ 0.25. With the same DEALO mole fraction during growth, the incorporation of Al and O was found to be independent
of x, but the compensation of Si donors decreases with increasing In content. Deep level transient spectroscopy analysis on
a series of InxGa1-xAs: Si. samples with 0 ≤ x ≤ 0.18 revealed that oxygen incorporation led to a set of deep levels, similar to those found in
DEALO doped GaAs. As the In composition was increased, one or more of these deep levels became resonant with the conduction
band and led to a high electron concentration in oxygen doped In0.53Ga0.47As. Low temperature photoluminescence emission measurements at 12K on the same set of samples revealed the quenching of the
near-band edge peak, and the appearance of new oxygen-induced emission features. DEALO doping in InP has also led to the incorporation
of Al and O, and the compensation of Si donors due to oxygen-induced multiple deep levels. 相似文献
35.
36.
高强IF钢析出物的析出特征 总被引:3,自引:0,他引:3
高强IF钢是汽车用深冲钢板中深冲性能最好的高强度钢板。目前,国际上对该钢种的研究十分活跃。本文在实验条件下,通过对高强IF钢析出物的观察研究了高强IF钢析出物的析出特征,发现了新的析出相TiFeP,并对磷对深冲性能影响的作用机制,进行了探讨。 相似文献
37.
胜利油田东营深层盐膏地层发育,盐膏段厚度大,分布范围广,地层岩性十分复杂,钻井中经常发生喷、漏、塌、卡,遇阻、划眼、电测遇阻等井下复杂事故。郝科1井是在该区设计的一口重点深探井,宅钻井深5807.81m,井底最高温度230℃。介绍了深层盐膏层钻井液体系的转化工艺、性能控制、维护处理、防漏、堵漏、固相控制、抗污染和钻具缓蚀等技术,以及MMH聚合物饱和盐水钻井液在郝科1井的成功应用。结果表明,该钻井液在高密度下对盐膏层具有较强的抑制性、悬浮携砂性和抗污染性,抗温220—230℃。MMH聚合物饱和盐水钻井液体系及其配套技术满足了深层盐膏层钻井施工需要。 相似文献
38.
随着计算机技术的发展和水平的提高,图像,声音,图形等多媒体信息逐步应用于管理信息系统之中。文章中提出了图文数据库系统设计中存在的三个基本问题。讨论了介绍了图文数据库系统的设计方法和实现技术。 相似文献
39.
On the basis of systematic studies of intense methods for metal forming, a production scheme has been developed, substantiated by experiment and realized for manufacturing molybdenum wire. The main stages are helical rolling of small rounded bars, vibratory drawing with induction heating of wire billets, and cold wire drawing with hydrodynamic introduction of lubricant and application to the tool of vibration in the transitional stages of the process (start-up, speed-up, slow-down, and stopping the pulling tool drive). 相似文献
40.
A variable friction model that relates the parameters of sheet metal drawing to the local lubrication conditions taking place during the deformation, has been integrated to a finite element program. Variable friction coefficients for the contacting surfaces are determined from the friction model, which uses the related parameters obtained at each time step of the finite element program as inputs. A number of numerical runs have been performed and the strains are compared with the experimental results for circular blanks. A good agreement is obtained between the numerical and experimental results for the variable friction model used. 相似文献