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The recent development of personal digital collections systems on museum websites has prompted researchers to examine the motivations and expectations of museum visitors as they interact with those systems. Results from an online survey completed by visitors to six different museum websites show that users of personal digital collections systems are primarily motivated by a desire to create simple collections of objects and images, and are less influenced by the more complicated features museums have implemented to encourage user participation. The significance of these findings is explored through a discussion of user expectations and motivations with respect to creating personal digital collections, and an attempt is made to reconcile some of the disparities between the perceptions of survey respondents and the experiences of museum professionals developing and implementing personal digital collections systems.  相似文献   
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This study assessed muscular torque and rate of torque development following concentric (CON) or eccentric (ECC) isokinetic training. Thirty-eight women were randomly assigned to either CON or ECC training groups. Training consisted of knee extension and flexion of the nondominant leg three times per week for 20 weeks (SD = 1). Eccentric training increased ECC knee extension and flexion peak torque more than CON training. The ECC group improved acceleration time and time to peak torque with ECC movements versus the CON group. Slow-velocity ECC isokinetic training yielded greater ECC and similar CON torque development gains versus CON training over the course of 20 weeks in young women.  相似文献   
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F. Fallside 《Endeavour》1979,3(2):63-68
While the majority of those afflicted with deafness must still seek relief by conventional methods, new technological developments open up the possibility of aids of quite novel kinds. This article reviews the principal lines of research now being pursued.  相似文献   
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The classical criteria for controllability and observability are given a tensorial formulation which is then extended into Boolean form directly related to a digraph interpretation of system structure. This is examined in detail with particular reference to group theoretic aspects, invariant properties under transformation, the term rank test and the existence of zero eigenvalues.Within this framework the structural design concepts of potential controllability and observability are presented in generalised terms.  相似文献   
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The graph theoretic aspects of controllability and observability are examined and related to the tensorial formulation of Part I of the paper. Particular emphasis is given to the significance of the system digraph decomposition and the relevance of this to certain system algebraic properties of interest in control theory.  相似文献   
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48 healthy neonates born to multiparae were randomly assigned to view a moving stimulus either in the horizontal or the upright position, with or without added vestibular stimulation and with or without pacifier sucking. The infant was shown a moving black line inside a strictly controlled visual environment provided by an apparatus which permitted horizontal and upright positioning and displacement of the infant. Visual tracking was recorded by a concealed TV camera positioned at a constant distance and angle from the infants' eyes in both positions. Quality of tracking during each of 4 trials was scored on a 7-point scale. Results indicate that vestibularproprioceptive stimulation provided to the infant either horizontally or semivertically significantly enhanced his visual tracking, whereas the upright position did not. Pacifier sucking also improved his performace.  相似文献   
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