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A hardware-and-software system is described that permits musical-bandwidth signal quantization, monophonic or stereophonic, direct to/from hard disk. The system, which uses an IBM AT or compatible, is cost effective and device independent. Software functions allow for automated aural and graphical signal analyses. Perceptual experiments that use contextual, natural-instrument stimuli, and that take advantage of the immediate and random access provided by this system, are described.  相似文献   
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This paper develops hypotheses about the implications of different types of decision for the utilization of different types of systematically produced information: data, research, and analysis. The engineering and enlightenment models found in the knowledge utilization literature prove inadequate for this purpose. We turn to three decision models—routine, incremental, and fundamental–and determine their implied demands for information. We also examine how information might be used in scanning procedures in anticipation of decision regime shifts. The results suggest that patterns of information should differ markedly in each decision context and indicate that there may be an inherent bias against the use of research in decision. Evert A. Lindquist, a doctoral candidate at the Graduate School of Public Policy, University of Calfornia at Berkeley, is completing a dissertation onPolicy Institutes in Canada: The Organization and Relevance of Public Inquiry and will join the faculty of the Department of Political Science at the University of Toronto this fall. Organizations, public policy, and the role of information in decision making are among his primary research interests.  相似文献   
196.
This paper describes an amplifier for an electroencephalograph with gain of 1×104 to 1×106 and made entirely of commercially available IC components. The two-stage amplifier has a preamplifier stage with fixed gain of 1000, and a second stage with variable gain from 1 to 100. The final stage, an anti-aliasing filter, adds a gain of 10 to the signal. The circuit has high common mode rejection, low input bias current, very low noise characteristics, low offset voltages, and offset nulling capability built into the circuit.  相似文献   
197.
We outline a BASIC program and subsidiary machine language timing routines that enable the Apple II series of computers to be employed as control devices for the tachistoscopic presentation of 35-mm slides and the collection of response latencies. The program is functional for experiments that require pictorial stimuli to be presented in up to three separate fields, with precise display times, precise interstimulus and intertriai intervals, and the collection of manual or vocal reaction times with millisecond accuracy. The major advantages of this system are that initial setup costs are substantially lower than those for other similar systems (e.g., Loftus, Gillispie. Tigre, & Nelson, 1984) and that user customization of the program may be accomplished by anyone possessing rudimentary knowledge of the BASIC programming language.  相似文献   
198.
A unique relationship exists between physicians and philosophers — one that expands on the constructive potential of the liaison between physicians and, for example, theologians, on the one hand, or, social workers on the other. This liaison should focus in the scientific aspects of medicine, not just the ethical aspects. Philosophers can provide physicians with a perspective on both the philosophy and the history of medicine through the ages — a sense of how medicine has adapted to the social cultural and ethical needs of each period. This perspective, while emphasizing medicine asscience, should not be limited to matters of methodology, or to criteria for distinguishing science from other intellectual pursuits, but should be concerned also with the history, sociology and politics of science. Both physicians and philosophers stand to gain from a strengthening of their active liaison now as never before; but most of all, the public will be the beneficiary.  相似文献   
199.
Fear of Success (FOS) was originally conceived as a unidimensional motive. However, there is both theoretical and empirical support for the hypothesis that FOS is multidimensional. We factor analyzed the responses of 236 undergraduates to twenty-oneConcern Over the Negative Consequences of Success items and found four factors. Our four factors show considerable overlap with dimensions based on theoretical accounts of FOS etiology as well as with the factor structures obtained from two other factor analytic studies. Thus, there is converging evidence that FOS is multidimensional. The relationship between multidimensional FOS and a multidimensional approach to achievement motivation is discussed.  相似文献   
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