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A new technology is considered for realizing the motion of solid body in the loose material due to alternating pulse ejections of compressed gas in the regime of traveling wave near the outer surface of the body. The dimensionless parameters are determined for scale modeling. The relation between the action factors and the value of motion is established empirically. 相似文献
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工程监理取费偏低,阻碍监理行业发展 总被引:1,自引:0,他引:1
工程监理制在我国建筑市场中,对提高工程质量、控制投资效益起着极其重要的作用,目前我国工程监理行业在低取费的条件下,困难重重,只能维持低水平运行。我们应找出存在的差距,采取相应的措施,适当提高监理取费,使监理行业迅速发展壮大。 相似文献
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不良的生活方式和个人行为对健康是一种“自我制造的危害”。吸烟有害世人皆知,然而,近年来吸烟大军更表现为年青化、女性化的特点,青年大学生们吸烟也较普遍,烟草危害在吸烟者身上表现也很明显,已给国家造成极大的疾病负担;青年大学生吸烟还有漫延之势,必须积极开设健康教育,传授保健知识,让他们自己起来同不良的生活习惯作斗争,同时,还必须制定有效的行政干预措施,才能把吸烟带来的毒害控制在最小范围。 相似文献
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本市第二毛纺厂中南楼是一幢三层四跨的纯框架结构,它在1976年7月28日的唐山地震中,结构遭受了严重的破坏.后经过加固,在同年的11月15日的宁河地震作用下,房屋全部倒塌,笔者利用平面杆系模型,对其结构进行弹塑性分析,以期得到影响该房屋倒塌的因素。 相似文献
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The aim of this study was to bring to the surface the strategic use of imitative processes in the context of a 2-route model: (a) direct imitation, used in reproducing new, meaningless actions, and (b) imitation based on stored semantic knowledge of familiar meaningful actions. Three experiments were carried out with healthy participants who reproduced meaningful and meaningless actions within an established time limit. The study investigated 3 factors that could potentially affect the selection of processes used for imitation: (a) the composition of the experimental list (blocked or mixed presentation), (b) the presence-absence of instructions (Experiments 1 and 2), and (c) the relative proportions of the stimuli (Experiment 3). Overall, the results suggest that each of these factors influences the selection of imitative strategies in healthy individuals with temporarily reduced capacities, as happens in the case of brain-damaged patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Previous research yielded inconsistent results regarding the memory organization of self-performed actions. The authors propose that task performance changes the very basis of memory organization. Enactment during study and test (Experiment 1) yielded stronger enactive clustering (based on motor-movement similarities), whereas verbal encoding yielded stronger conceptual clustering (based on semantic-episodic similarities). Enactment enhanced memory quantity and memory accuracy. Both measures increased with enactive clustering under self-performance instructions but with conceptual clustering under verbal instructions. Enactment only during study (Experiment 2) or only during testing (Experiment 3) also enhanced enactive clustering. It is proposed that different conditions affect the relative salience of different types of memory organization and their relative contribution to recall. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Visually perceiving an action may activate corresponding motor programs. This automatic motor activation can occur both for higher level (i.e., the goal of an action) and for lower level (i.e., the specific effector with which it is executed) aspects of an action. The authors used a tool-use action paradigm to experimentally dissociate priming effects for observing the target, the movement, or the target-to-movement mapping of a tool-use action. In 3 experiments, participants took turns in acting, observing the tool-use action of another person in trial n-1, and executing an action in trial n. Trial transitions from n-1 to n were manipulated in 4 conditions with (a) mapping repeated and movement and target changed, (b) target repeated and movement and mapping changed, (c) movement repeated and target and mapping changed, or (d) all components repeated. Results indicate priming effects for repeating the target-to-movement mapping (i.e., the action rule) of a tool-use action and suggest that a rather abstract action schema is activated during action observation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献