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51.
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   
52.
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   
53.
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   
54.
Many studies directed at demonstrating perception without awareness have relied on the dissociation paradigm. Although the logic underlying this paradigm is relatively straightforward, definitive results have been elusive in the absence of any general consensus as to what constitutes an adequate measure of awareness. We propose an alternative approach that involves comparisons of the relative sensitivity of comparable direct and indirect indexes of perception. The only assumption required by the proposed approach is that the sensitivity of direct discriminations to relevant conscious information is greater than or equal to the sensitivity of comparable indirect discriminations. The proposed approach is illustrated through an evaluation of Avant and Thieman’s (1985) recent claim that an indirect measure of perception based on judgments of apparent visual duration provides a more sensitive indicator of perception than does a direct measure based on forced-choice recognition. Contrary to this claim, when direct and indirect indexes are measured under comparable conditions, an indirect measure based on judgments of perceived duration provides a less sensitive index of perceptual processing than do comparable direct measures. The proposed approach provides a general conceptual/methodological framework for using the dissociation paradigm in studies directed at establishing unconscious processes.  相似文献   
55.
A previous study (Leung, Bond, & Schwartz, 1990) established that an expectancy-valence model could be used effectively to explain behaviours in three social domains both within and across cultures. In this study the model was applied to the domains of resource allocation and conflict resolution in order to pinpoint which expectancies and which valences were carrying the explanatory weight of the respondents' behavioural strategies. For both Israeli and Hong Kong students the expectancies and, less strongly, the valences tapping harmony and performance quality were important for resource allocation; those tapping animosity reduction and process control, for conflict resolution. Suggestions were offered for broadening the net of explanatory constructs for future work aimed at specifying subjective factors associated with justice-related behaviours.  相似文献   
56.
Effects of persuasive messages, responsibility denial (RD), and attitude-accessing on blood-giving attitudes, intentions, moral obligations, and behavior were examined. In Study 1, participants (n= 84) who heard a message emphasizing moral reasons for donating indicated a more favorable postmessage attitude and stronger moral obligation to donate than participants exposed to a message aimed at reducing fear, a combined moral and fear- reduction message, or no message. Combined message participants showed greatest intent to donate, yet only 14% of all participants attended a campus drive. In Study 2, low (n= 52) and high (n= 60) RD individuals heard the message arguments and were asked to access their attitudes. Low compared to high RD individuals stated a stronger sense of moral obligation, particularly when they accessed their thoughts relevant to blood donating, and behavioral intention, especially in the combined message condition. Few participants attended a blood drive (12.5%), yet most were low RD individuals from the nonaccessed attitude condition (83%). Results suggest that few individuals will engage in the altruistic act of blood donating, despite the experimental use of persuasive messages and accessing issue-relevant attitudes.  相似文献   
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