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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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Recently, March, Hooper, and Baum (1977) described a sample of 99 nonstudent elders in terms of their demographic characteristics and their attitudes toward lifelong learning. The sample was found to be well‐educated (mean years of education = 13.61, SD = 9.43), active in the community, well‐read, and fairly affluent. The majority demonstrated a quite open attitude toward the appropriateness of formal education in old age, but also felt that learning can be acquired outside the classroom: “living is learning.” The present study was undertaken to similarly describe a sample of elderly people enrolled in the University of Wisconsin guest student program, and to contrast these respondents with those in the earlier study. The student group was found to be significantly younger than the nonstudent group (mean = 70.78, SD = 7.21 vs. mean = 74.69, SD = 8.45; t = 2.87, p < .001). Although there is no difference in the mean years of education of the two groups, there is significantly greater variability in years of education in the student group (F = 10.98, p < .001), with 50.4% of the nonstudent group versus 21.6% of the student group having 12 years of education or less. Additionally, it was found that only 10 of the 139 student respondents did not have either personal or vicarious personal (through familial significant others) experience with higher education in youth. The respondents’ stated preference for class format and student group age is also summarized, and some implications for educational gerontology are discussed. 相似文献
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