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61.
Children's and adults' recognition of spontaneous and posed emotional expressions in young children.
Felleman Elyse S.; Carlson Charles R.; Barden R. Christopher; Rosenberg Lois; Masters John C. 《Canadian Metallurgical Quarterly》1983,19(3):405
Investigated the degree to which 4–5 yr olds (n?=?48) can enact expressions of emotion recognizable by peers and adults; the study also examined whether accuracy of recognition was a function of age and whether the expression was posed or spontaneous. Adults (n?=?103) were much more accurate than children in recognizing neutral states, slightly more accurate in recognizing happiness and anger, and equally accurate in recognizing sadness. Children's spontaneous displays of happiness were more recognizable than posed displays, but for other emotions there was no difference between the recognizability of posed and spontaneous expressions. Children were highly accurate in identifying the facial expressions of happiness, sadness, and anger displayed by their peers. Sex and ethnicity of the child whose emotion was displayed interacted to influence only adults' recognizability of anger. Results are discussed in terms of the social learning and cognitive developmental factors influencing (a) adults' and children's decoding (recognition) of emotional expressions in young children and (b) encoding (posing) of emotional expressions by young children. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
63.
This paper gives an evaluation of a low-cost MEMS accelerometer. The accelerometer is intended for the distance measurement of a mobile robot or platform in short duration. The distance traveled is obtained by double integration of the sensor signal with time. Bias offset drift exhibited in the acceleration signal is accumulative and the accuracy of the distance measurement can deteriorate with time due to the integration. This problem can be fixed by periodic recalibration with the help of external measurements on position, velocity and attitude. These external signals can be calculated by an inertial system. A Kalman filter can use the differences between these values to provide an optimum estimate of the system error. The random bias drift of the accelerometer was found by experiment to be 2.5 mg. The bias drift rate due to temperature was 0.108 g/s when the accelerometer was placed at room temperature. With proper compensation on gravitation, the accelerometer can be a viable solution as a short duration distance-measuring device for a mobile robot. 相似文献
64.
Hugh Spikes 《Tribology International》2001,34(12)
This paper attempts to predict and discuss some of the many challenges facing fundamental research in tribology over the first half of the new century. This is done in two stages, looking at likely developments over the first twelve years based on extrapolation of existing trends, and then, more speculatively, considering possible driving forces over subsequent decades. 相似文献
65.
After very high growth in the 1980s, geothermal electricity production has slowed in the mid- and late-1990s. While Japanese, Indonesian and Philippine geothermal growth has remained high as a consequence of supportive government policies, geothermal electricity production has been flat or reduced in much of Europe and North America. Low prices for coal and natural gas, combined with deregulation, means that in much of the world electricity from new fuel-burning electricity plants can be provided at half the cost of new geothermal electricity. Cost-cutting must be pursued, but is unlikely to close the price gap by itself. Geothermal production is widely perceived as being environmentally clean, but this is not unambiguously true, and requires reinjection to be fully realized. Strategies for monetizing the environmental advantages of geothermal, including the carbon tax, are discussed. 相似文献
66.
An “autorating” (peer rating) system designed to account for individual performance in team projects was used in two sophomore‐level chemical engineering courses in which the students did their homework in cooperative learning teams. Team members confidentially rated how well they and each of their teammates fulfilled their responsibilities, the ratings were converted to individual weighting factors, and individual project grades were computed as the product of the team project grade and the weighting factor. Correlations were computed between ratings and grades, self‐ratings and ratings from teammates, and ratings received and given by men and women and by ethnic minorities and non‐minorities. Incidences of “hitchhikers” (students whose performance was considered less than satisfactory by their teammates), “tutors” (students who received top ratings from all of their teammates), dysfunctional teams, and teams agreeing on a common rating were also determined. The results suggest that the autorating system works exceptionally well as a rule, and the benefits it provides more than compensate for the relatively infrequent problems that may occur in its use. 相似文献
67.
Hugh C. Marles 《History of Photography》2013,37(4):395-396
Abstract In this 1986 article ‘The Body and the Archive’, Alan Sekula argues that the Essays on Physiognomy of Johann Casper Lavater, which were published in the 1770s, helped to establish a belief that was augmented and elaborated during the nineteenth century through the use of photography.1 To give an example, Francis Galton based much of his photographic work on the premise that the surface of the body could provide an observer with clues about the inner character of an individual, a virtually timeless supposition that Lavater had revived and systematized. Of course, nineteenth-century physiognomic studies aimed to corroborate a wide range of assumptions about the social and biological status of the individual, which may be seen as responses to the socioeconomic needs of the time — Galton's eugenic theories are generally cast against the background of growing, impoverished urban populations in the second half of the century.2 Nevertheless, Lavater's original delineation of the subject of physiognomy may provide us with a valuable starting point for the study of nineteenth-century work in that area, and this holds true when we come to examine the work of Duchenne of Boulogne, whose Le Mçcanisme de la Physionomie Humaine was published in Paris in 1862. 相似文献
68.
The thermodynamic work of adhesion between micron-sized zirconia or carbon spheres and polyester-melamine surfaces was determined using the Johnson-Kendall-Roberts (JKR) relationship, after first validating the JKR approach for this system. The calculated works of adhesion for both zirconia and carbon were similar for any given substrate composition and were found to be approximately 35 mJ/m2 at low melamine concentrations, close to theoretical predictions. The apparent work of adhesion decreased with increasing melamine concentration, most likely due to the presence of a glassy melamine-rich surface layer, which is not representative of the bulk. The value found for low melamine concentration was assumed to be a true value for cocondensed polyester-melamine, and this was used to estimate surface modulus and the amount of excess melamine in the surface as a function of bulk composition. 相似文献
69.
Vann Seralynne D.; Denby Christine; Love Seth; Montaldi Daniela; Renowden Shelley; Coakham Hugh B. 《Canadian Metallurgical Quarterly》2008,22(5):658
Despite increasing evidence that the fornix is important for memory, uncertainty remains about the exact nature of subsequent impairments arising from damage to this tract. This uncertainty is often created by pathology in additional brain structures. The present study involved a young man, DN, who had almost complete bilateral loss of the rostral columns of the fornix and much of the surrounding septum in the left hemisphere following the surgical removal of a cavernous angioma. Quantitative MRI analyses of structure size, normalized to intracranial volume, showed no difference in any of the additional brain regions measured, apart from those areas removed to expose the tumor. DN showed a marked, stable anterograde memory impairment that was still present 4 years postsurgery. In contrast, DN performed within normal levels on most tests of recognition memory. This sparing was most striking when given a 24-hr delay between study and test of the Warrington Recognition Memory Test. This recall/recognition dissociation provides further evidence for neuroanatomical divisions within recognition memory processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.