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161.
Improvements in the computing power and visual resolution of modern desktop computing systems, as well as advances in software technology for displaying high-speed animations, have encouraged the development of relatively sophisticated real-time flight simulators for the PC and Macintosh. We review some of the factors that determine how well such programs capture the actual experience of flight. The most significant factor limiting the quality of performance in flying a simulated aircraft is the “frame rate” problem: at low altitudes and in highly detailed visual environments, as in approaching a runway threshold during landing, the computational demands of the animation may necessitate a reduction in the number of frames displayed per second on the screen. The delayed sensory feedback that results proves to be very detrimental to sustaining smooth control of the aircraft, especially during the flare to touchdown where such control is needed most. This finding parallels the well-known effects of delayed auditory feedback (Lee, 1950) and delayed visual feedback (Smith, 1962). 相似文献
162.
Richard M. Warren Keri R. Riener James A. Bashford Bradley S. Brubaker 《Attention, perception & psychophysics》1995,57(2):175-182
The intelligibility of word lists subjected to various types of spectral filtering has been studied extensively. Although words used for communication are usually present in sentences rather than lists, there has been no systematic report of the intelligibility of lexical components of narrowband sentences. In the present study, we found that surprisingly little spectral information is required to identify component words when sentences are heard through narrow spectral slits. Four hundred twenty listeners (21 groups of 20 subjects) were each presented with 100 bandpass filtered CID ( “everyday speech ”) sentences; separate groups received center frequencies of 370, 530, 750, 1100, 1500, 2100, 3000, 4200, and 6000 Hz at 70 dBA SPL. In Experiment 1, intelligibility of single 1/3-octave bands with steep filter slopes (96 dB/octave) averaged more than 95% for sentences centered at 1100, 1500, and 2100 Hz. In Experiment 2, we used the same center frequencies with extremely narrow bands (slopes of 115 dB/octave intersecting at the center frequency, resulting in a nominal bandwidth of l/20 octave). Despite the severe spectral tilt for all frequencies of this impoverished spectrum, intelligibility remained relatively high for most bands, with the greatest intelligibility (77%) at 1500 Hz. In Experiments 1 and 2, the bands centered at 370 and 6000 Hz provided little useful information when presented individually, but in each experiment they interacted synergistically when combined. The present findings demonstrate the adaptive flexibility of mechanisms used for speech perception and are discussed in the context of the LAME model of opportunistic multilevel processing. 相似文献
163.
Bradley Bucher 《Journal of experimental child psychology》1973,15(1):10-21
Children were given instructions to perform different tasks. Compliance was studied as a function of several variables: the prevailing pattern of reinforcement for different instructions, the availability of a competing reinforced activity, and the similarity among tasks. Rate of compliance tended to decrease when the probability of reinforcement for compliance decreased, or when a competing reinforced activity was available. Differential reinforcement over the tasks did not always produce discriminative responding even under favorable conditions. Novel instructions obtained compliance at the same rate as that for frequently repeated instructions, independent of the novel instruction's past or present reinforcement history. Greater discrimination in responding was found when tasks were less similar. Results imply that sets of instructions may form a response class, with characteristics similar to those found in studies of generalized imitation. 相似文献
164.
The present study attempted to evaluate experimentally the relationship between two response classes: cooperative play and speech. One child was observed in a preschool free-play setting. Base rates of speech and play with peers indicated that the child never spoke to or played with peers during free-play periods. Base rates of teacher attention were observed to fluctuate directly with the child's isolate play. When differential attention and extinction operations were presented, removed and presented again, the frequency of cooperative play with peers increased, decreased and increased accordingly. Moderate fluctuations in verbal behavior also correlated with the presence and absence of the differential attention and extinction operations, even though the operations were applied only to cooperative play. The results suggest that some nonverbal isolate children may begin producing speech when play behaviors with peers are reinforced by teachers. 相似文献
165.
D J Bradley 《Perceptual and motor skills》1989,69(1):3-8
Some rune verses are, apparently, thematically derived from Chinese Radical sequences. The 33 runes are, like the Sanskrit letters, mnemonically valenced and formally associated with the nervous system. 相似文献
166.
Catherine T. Best Harry Hoffman Bradley B. Glanville 《Attention, perception & psychophysics》1982,31(1):75-85
Groups of 2-, 3-, and 4-month olds were tested for dichotic ear differences in memory-based phonetic and music timbre discriminations. A right-ear advantage for speech and a left-ear advantage (LEA) for music were found in the 3- and 4-month-olds. However, the 2-month-olds showed only the music LEA, with no reliable evidence of memory-based speech discrimination by either hemisphere. Thus, the responses of all groups to speech contrasts were different from those to music contrasts, but the pattern of the response dichotomy in the youngest group deviated from that found in the older infants. It is suggested that the quality or use of lefthemisphere phonetic memory may change between 2 and 3 months, and that the engagement of right-hemisphere specialized memory for musical timbre may precede that for left-hemisphere phonetic memory. Several directions for future research are suggested to determine whether infant short-term memory asymmetries for speech and music are attributable to acoustic factors, to different modes or strategies in perception, or to structural and dynamic properties of natural sound sources. 相似文献
167.
Examined subjects' acceptance of genuine, test-based personality feedback as a function of diagnostician prestige and sex, subject sex, and diagnostician. It was found that subjects of both sexes rated the feedback provided by female diagnosticians as significantly more accurate than that provided by male diagnosticians. This was attributable in part to a tendency for subjects to greatly devalue the feedback provided, by low prestige, male diagnosticians, Support for the generalizability of the present results from the social psychological literature was noted and suggestions for future research were provided. 相似文献
168.
An operant-based corrective reading program was established to study effectiveness of peer tutoring in the school, for reading deficient children. Sixty-nine second to fourth grade students were matched on measures of initial reading ability and level of reading retardation, and randomly assigned to three groups: Peer Tutoring Only, Peer Tutoring with Home Based Reinforcement, and Control. SRA materials were used in training for the experimental groups, supplemented with additional reading materials. The program continued for 15 weeks, in seven public schools. Changes in oral reading accuracy and comprehension were assessed. Both reading and comprehension were significantly increased by peer tutoring, relative to the control group. The addition of home-based reinforcement doubled this increase. The measured gain in oral reading, based upon standardized testing, was 0.19 years for the controls and 1.27 years for peer tutoring with home-based reinforcement. Internal measures of gain showed similar results, and comprehension gains were also comparable. A high rate of compliance with the tutoring program was maintained by the tutors. High ratings of satisfaction were obtained for the program, from all groups of participants. The feasibility of the program for application in the school system is discussed. 相似文献
169.
College students' acceptance of general personality interpretations was evaluated as a function of type of test and assessment device employed and interpretation favorability. Unlike previous studies, only interpretation favorability influenced acceptance. The effect of interpretation favorability upon acceptance, however, was shown to be due to the higher base-rate accuracy of favorable, relative to unfavorable, interpretations. It was concluded that the universal validity of general interpretations may supersede the effects of situational factors upon acceptance. 相似文献
170.