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Book review     
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This paper deals with real-time discrete adaptive output trajectory tracking for induction motors in the presence of bounded disturbances. A recurrent high order neural network structure is used to design a nonlinear observer and based on this model, a discrete-time control law is derived, which combines discrete-time block control and sliding modes techniques. Applicability of the scheme is illustrated via experimental results in real-time for a three phase induction motor.  相似文献   
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In order to plan appropriate cooperative programs for particular higher education consortia, it is necessary to identify the characteristics of these organizations. The spatial configuration technique was used to illustrate the impact of eleven variables of the member institutions in differentiating among four consortia. Six of the variables — Control, Highest Degree Awarded, Percentage of Males, Math SAT Scores, Conventional Orientation, Scientific Orientation, and Endowment — were found to be significant in differentiating among the consortia. It was concluded that the spatial configuration technique was an effective way of visually comparing those consortia composed of member institutions, which as groups had similar and dissimilar characteristics.  相似文献   
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This study examined how timing (i.e., relative maturity) and rate (i.e., how quickly infants attain proficiency) of A‐not‐B performance were related to changes in brain activity from age 6 to 12 months. A‐not‐B performance and resting EEG (electroencephalography) were measured monthly from age 6 to 12 months in 28 infants and were modeled using logistic and linear growth curve models. Infants with faster performance rates reached performance milestones earlier. Infants with faster rates of increase in A‐not‐B performance had lower occipital power at 6 months and greater linear increases in occipital power. The results underscore the importance of considering nonlinear change processes for studying infants’ cognitive development as well as how these changes are related to trajectories of EEG power.  相似文献   
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正Arthrospira maxima (Spirulina) is a cyanobacterium which is considered a nutraceutical because it has antioxidant, anti-inflammatory, and cytoprotective properties in different renal disease models (RodriguezSánchez et al., 2012; Aziz et al., 2018; Memije-Lazaro et al., 2018).  相似文献   
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This paper proposes a typology of communities of practice based on their knowledge characteristics. The structure of a community of practice, in terms of knowledge, may tend to the stratified or to the egalitarian. The predominant knowledge activity of the community may be sharing or nurturing. This produces four classes of community of practice. The paper identifies and discusses examples of these classes. It is argued that the class to which a community belongs tends to determine the rapidity with which knowledge within the community evolves and the degree of pluralism, as opposed to homogeneity, that the knowledge exhibits. The paper concludes by discussing some of the implications of the typology for knowledge management practice.  相似文献   
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