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101.
The related goals of the research were to delineate the domain of discontinuity, 1st by demonstrating its occurrence in a nonmatrix situation and, 2nd, by establishing the antecedent outcome conditions necessary for producing a discontinuity effect. The 1st goal was met by designing a mixed motive situation involving the production of origami products. Under these conditions, the magnitude of the discontinuity effect did not significantly differ from that in a matrix-only condition. The 2nd goal was met by a separate experiment that used H. H. Kelley and J. W. Thibaut's (1978) analysis of degree of noncorrespondence of outcomes. This experiment demonstrated that as noncorrespondence increased, so did the rate of competitive responding by groups but not by individuals. This pattern was qualified by an interaction with gender such that competitiveness was more markedly affected by noncorrespondence for groups of women than for groups of men. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper profiles research relating to the robotic assembly, inspection, and maintenance of space solar-power facilities. Free-flying robots, fixed-base manipulators, and attached mobile manipulators are examined, the technical challenges facing them are outlined, and their roles in the construction process are illuminated. Themes include autonomous materials delivery, warehousing, large-scale payload handling and mating, payload attachment in confined spaces, and inspection. Research has addressed a fraction of the technologies needed to perform reliable autonomous assembly, inspection, and maintenance. Areas in need of further development are examined and potential research is outlined. Current technology cannot fulfill the requirements of orbital construction. The research and development needed can be completed in the near future, and substantive assembly inspection and maintenance can be achieved.  相似文献   
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Get ‘em young     
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This paper studies nested simulation and nested trace semantics over the language BCCSP, a basic formalism to express finite process behaviour. It is shown that none of these semantics affords finite (in)equational axiomatizations over BCCSP. In particular, for each of the nested semantics studied in this paper, the collection of sound, closed (in)equations over a singleton action set is not finitely based.  相似文献   
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Drivers are not always aware that they are becoming impaired as a result of sleepiness. Using specific symptoms of sleepiness might assist with recognition of drowsiness related impairment and help drivers judge whether they are safe to drive a vehicle, however this has not been evaluated. In this study, 20 healthy volunteer professional drivers completed two randomized sessions in the laboratory – one under 24 h of acute sleep deprivation, and one with alcohol. The Psychomotor Vigilance Task (PVT) and a 30 min simulated driving task (AusEdTM) were performed every 3–4 h in the sleep deprivation session, and at a BAC of 0.00% and 0.05% in the alcohol session, while electroencephalography (EEG) and eye movements were recorded. After each test session, drivers completed the Karolinska Sleepiness Scale (KSS) and the Sleepiness Symptoms Questionnaire (SSQ), which includes eight specific sleepiness and driving performance symptoms. A second baseline session was completed on a separate day by the professional drivers and in an additional 20 non-professional drivers for test–retest reliability. There was moderate test–retest agreement on the SSQ (r = 0.59). Significant correlations were identified between individual sleepiness symptoms and the KSS score (r values 0.50–0.74, p < 0.01 for all symptoms). The frequency of all SSQ items increased during sleep deprivation (χ2 values of 28.4–80.2, p < 0.01 for all symptoms) and symptoms were related to increased subjective sleepiness and performance deterioration. The symptoms “struggling to keep your eyes open”, “difficulty maintaining correct speed”, “reactions were slow” and “head dropping down” were most closely related to increased alpha and theta activity on EEG (r values 0.49–0.59, p < 0.001) and “nodding off to sleep” and “struggling to keep your eyes open” were related to slow eye movements (r values 0.67 and 0.64, p < 0.001). Symptoms related to visual disturbance and impaired driving performance were most accurate at detecting severely impaired driving performance (AUC on ROC curve of 0.86–0.91 for detecting change in lateral lane position greater than the change at a BAC of 0.05%). Individual sleepiness symptoms are related to impairment during acute sleep deprivation and might be able to assist drivers in recognizing their own sleepiness and ability to drive safely.  相似文献   
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We have demonstrated, for the first time, a novel three-dimensional (3D) memory chip architecture of stacked-memory-devices-on-logic (SMOL) achieving up to 95% of cell-area efficiency by directly building up memory devices on top of front-end CMOS devices. In order to realize the SMOL, a unique 3D Flash memory device and vertical integration structure have been successfully developed. The SMOL architecture has great potential to achieve tera-bit level memory density by stacking memory devices vertically and maximizing cell-area efficiency. Furthermore, various emerging devices could replace the 3D memory device to develop new 3D chip architectures.  相似文献   
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