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201.
The person-by-situation interaction model of anxiety was tested in the reallife setting of an academic examination. Twenty-eight male and 79 female university students served as subjects. State anxiety (A-State) was assessed just prior to the examination (Trial 2) and approximately 1 week before (Trial 1) and after (Trial 3) the examination. Five facets of trait anxiety (A-Trait) were measured in a nonstressful situation 1 week prior to the examination. The subject's cognitive appraisal of the various situations was assessed by a self-report index of the type and degree of threat involved in the situation just experienced. As predicted, a significant A-Trait-by-situation interaction in eliciting A-State was observed for social evaluation A-Trait. There were no interactions for the other, noncongruent facets of trait anxiety. The results also indicated that individuals' perception of situations may be the most important factor affecting reactions to stressful situations. In general, the results were interpreted as providing support for the multidimensionality of A-Trait and further validation of the interaction model of anxiety.  相似文献   
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203.
Imagine if each square of pavement on the sidewalk had an owner, and pedestrians required a license to step on it. Imagine the negotiations necessary to walk an entire block under this system. That is what writing a program will be like if software patents continue. The sparks of creativity and individualism that have driven the computer revolution will be snuffed out. Imagine if each square of pavement on the sidewalk had an owner, and pedestrians required a license to step on it. Imagine the negotiations necessary to walk an entire block under this system. That is what writing a program will be like if software patents continue. The sparks of creativity and individualism that have driven the computer revolution will be snuffed out.—Richard Stallman and Simson Garfinkel (1992) This article highlights the vulnerability of the open source software movement to patent infringement lawsuits. With the number of patents on software algorithms predicted to exceed 100,000 this year, it is now virtually impossible to write any computer program, however trivial, that does not violate one or more patents. This paper argues that this situation is not only ludicrous, but it is contrary to any reasonable reading of the Constitution’s intentions with respect to the protection of intellectual property. In addition, the patentability of software algorithms stems from the U.S. Supreme Court’s failure to grasp one of the most fundamental concepts of computer science. From this error stems a long, dysfunctional chain of legal reasoning and patent policies, the effect of which has been to transform the mental reasoning processes, abstract knowledge, and scientific truths of computing into patentable subject matter. The result poses a potentially catastrophic threat not only to the open source software movement and the emerging industry of electronic commerce, but more fundamentally, to the very existence of the sciences of computing, without which further U.S. technological leadership will be impossible to sustain. An anthropologist, Dr. Pfaffenberger has authored dozens of how-to and reference books on computers and the Internet. He won the Albert Payson Usher Prize from the Society for the History of Technology and the Best Book of the Year Award from the American Society for Information Science.  相似文献   
204.
In two experiments, first- and fourth-grade subjects (age 6 and 9 years) performed a speeded card-sorting task with either integral or nonintegral dimensions. The dimensions were so arranged that subjects sorted on three types of task: (1) single dimension, (2) correlated dimensions, and (3) orthogonal dimensions. Results of the first experiment indicate that both first- and fourth-grade subjects sorted integral dimensions in a manner not qualitatively different from that of the adult (Garner & Felfoldy, Cognitive Psychology, 1970, 1, 225–241). In comparison with single-dimension tasks, performance was facilitated on the correlated-dimensions tasks and interference was observed on the orthogonal-dimensions tasks. Performances with nonintegral dimensions revealed an age-related processing difference. Fourth graders sorted nonintegral dimensions like the adult; no differences in performance were observed between the tasks. In contrast, first-graders sorted nonintegral dimensions as if they were integral. Interference was consistently observed on orthogonal-dimensions tasks. On correlated-dimensions tasks, interference was observed on easy tasks and redundancy facilitated difficult tasks. In the second experiment, first graders showed consistent facilitation on the correlated-dimensions task; all other results were indentical to those of Experiment I. The results were interpreted as consistent with perceptual learning theory (Gibson, Principles of perceptual learning and development. New York: Appleton-Century-Crofts, 1969).  相似文献   
205.
Conclusion Counterpart theorists need not posit the counterpart relation in addition to the identity relations as an Additional relation relating objects across possible worlds. Identity can be viewed as a relation applicable to individuals within possible worlds, while the counterpart relation replaces identity in translations of ordinary utterances which correlate individuals in different possible worlds and, hence, in all modal utterances. CT is, in other words, a theory of modal discourse — it proposes a way of understanding all modal predications. As such, it is not to be seen as providing a second looser sense of identity across worlds, in addition to the narrow sense. Perhaps Lewis' original formulation encourages this misunderstanding insofar as it (see, especially, P2) denies strict identity across possible worlds. Accordingly, I have suggested a modification of CT whereby syntactic restrictions upon variables eliminates any temptation to posit two parallel relations applicable to entities existing in different possible worlds.As has been argued by Alvin Plantinga, The Nature of Necessity, The Clarendon Press, (Oxford, 1974), Chapter VI.  相似文献   
206.
In three experiments, behavior maintained by fixed-interval schedules changed when response-independent reinforcement was delivered concurrently according to fixed- or variable-time schedules. In Experiment I, a pattern of positively accelerated responding during fixed interval was changed to a linear pattern when response-independent reinforcement occurred under a variable-time schedule. Overall response rates (total responses/total time) decreased as the frequency of response-independent reinforcement increased. Experiment II showed that the response-rate changes in the first experiment were controlled by the response-reinforcer relation, but the changes in patterns of responding were similar whether concurrently available reinforcement at varying times was response-dependent or response-independent. In the final experiment, the addition of response-independent reinforcement at fixed times to a fixed-interval schedule resulted in changes in both local and overall response rates and in the occurrence of positively accelerated responding between reinforcements. These results suggest that the temporal distribution of reinforcers determines response patterns and that both the response-reinforcement dependency and the schedule of reinforcement determine overall response rates during concurrently scheduled response-dependent and response-independent reinforcement.  相似文献   
207.
When people make errors during continuous tasks they temporarily pause and then slow down. One line of explanation has been that they monitor feedback to detect errors, that they may make incidental responses when errors occur (e.g. they may swear) and that they may pause to analyse their errors. In all these cases they may be assumed to act as single channel information processing systems of limited capacity, and to be unable to recognise any new signal until these processes have been completed.

Analysis of response after errors shows that this cannot be the case. Responses after errors are inaccurate, but are not slow when they require the subject to make the response which he should have made on the previous trial (i.e. to make an error correction response). Subjects thus must recognise new signals as soon as they occur. The present results require a new model of error detection and correction, and a model for response programming and priming.  相似文献   
208.
Effects of film material upon children's behavior   总被引:1,自引:0,他引:1  
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209.
The performance of a pictorial assessment instrument and suggestions for clinical application are described. The stylized family illustrations include the following patterns: normal family, detouring, two-generational enmeshment, three-generational enmeshment, parental child, undermined mother and chaotic family. Ninety-eight individuals, five years or older, in twenty families selected depictions most like their own families. Siblings of patients alone or siblings combined with fathers chose the same pattern type as the family therapists 75 and 64% of the time, respectively. These concordances were significant statistically. Clinical uses include identifying promising therapeutic resources and facilitating transitions to systems and relationship issues.  相似文献   
210.
This study was designed to delineate the course of sexual satiation in prairie voles (Microtus ochrogaster). Fourteen male-female pairs were allowed to copulate freely for 24 hr under continuous observation. Copulations occurred predominantly during the first few hours and decreased in frequency thereafter. The mean number of ejaculations per pair was 5.6 (range, 2-9). Two thirds of the ejaculations occurred during the first 3 hr, and over 90% took place within the first 7 hr after the first intromission. No ejaculations were observed during the last 8 hr. These results suggest that male capacity to deliver ejaculations to a female is limited and that direct observations reveal a more limited capacity than observations made with time-lapse videotape.  相似文献   
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