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31.
32.
Tachistoscopic presentation of stimuli on IBM PC-compatible computers is limited by a number of factors, including video retrace rates, screen scrolling, and the shape and density of picture elements. A method is presented for overcoming these difficulties through the use of enhanced graphic adapters or video graphic arrays. A C-language program demonstrates (1) synchronous scroll-free displays achieved by writing alternating images to “hidden” pages of video memory, (2) alternative techniques for erasing images, and (3) use of an empirically derived aspect ratio to produce symmetrical figures. 相似文献
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A study was conducted with 225 college students to examine the effects of three organizational and policy variables on the perceived fairness and invasiveness of drug-testing practices. Specifically, the effects of warning type (no warning vs. advance warning), consequence of a positive drug test (termination vs. rehabilitation), and safety sensitivity of the job (safety sensitive vs. safety nonsensitive) were examined. Results suggested that specific features of the policy, as well as type of job under consideration, affected perceived invasiveness and fairness of drug testing. In general, testing was seen as more appropriate for safety-sensitive jobs, that is, those in which drug-impaired performance presented a high degree of danger for individuals. Although rehabilitation was perceived as more fair than termination, when safety was an issue, termination was viewed as a justifiable response by the company. Implications for organizational drug-testing policies are discussed. 相似文献
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Nancy A. Neef Jeffrey Lensbower Idil Hockersmith Valerie DePalma Kevin Gray 《Journal of applied behavior analysis》1990,23(4):447-458
We analyzed the role of the range of variation in training exemplars as a contextual variable influencing the effects of in vivo versus simulation training in producing generalized responding. Four mentally retarded adults received single case instruction, followed by general case instruction, on washing machine and dryer use; one task was taught using actual appliances (in vivo) and the other using simulation. In vivo and simulation training were counterbalanced across the two tasks for the 2 subject pairs, using a within-subjects Latin square design. With both paradigms, more errors were made after single case than after general case instruction during probe sessions with untrained washing machines and dryers. These results suggest that generalization errors were affected by the range of training exemplars and not by the use of simulated versus natural training stimuli. Although both general case simulation and general case in vivo training facilitated generalized performance of laundry skills, an analysis of training time and costs indicated that the former approach was more efficient. The study illustrates a methodology for studying complex interactions and guiding decisions on the optimal use of instructional alternatives. 相似文献
37.
Rodger Beehler 《Studies in Philosophy and Education》1990,10(4):315-335
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise. 相似文献
38.
This study was designed to examine the correlates of developmental psychological stress for 36 middle-aged professional men. Based on sex role convergence and role adjustment theories, two sets of predictor variables were hierarchically entered into a multiple regression equation with a third set of variables entered to control for individual stressors. Controlling for individual stressors, midlife stress outcome was found to be influenced only by role adjustment (R2=.3593). The sex role convergence cluster did not account for a significant increase in variance. Controlling for individual stressors, the best univariate predictors of stress outcome associated with the midlife transition were (a) the quality of the parent-adolescent relationship and (b) marital satisfaction. 相似文献
39.
Kevin J. Sharpe 《Zygon》1990,25(1):105-122
Abstract. David Bohm's thinking has become widely publicized since the 1982 performance of a form of the Einstein-Podolsky- Rosen (EPR) experiment. Bohm's holomovement theory, in particular, tries to explain the nonlocality that the experiment supports. Moreover, his theories are close to his metaphysical and religious thinking. Fritjof Capra's writings try something similar: supporting a theory (the bootstrap theory) because it is close to his religious beliefs. Both Bohm and Capra appear to use their religious ideas in their physics. Religion, their source for physical hypotheses, provides the motivation to develop and uphold them. 相似文献
40.
Richard L. Port Heather A. Murphy R. DAniel Miller Kevin S. Seybold 《Current psychology (New Brunswick, N.J.)》1997,15(4):332-339
present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning
under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the
NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number
of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage
(.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition.
These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple
contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially
to spatial cognition, classical and instrumental conditioning. 相似文献