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51.
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
52.
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
53.
54.
It is often desirable to represent carrier distribution systems by networks so that analysis can be made to predict the behavior of these systems. Modeling of two canonical carrier distribution systems, the star-shaped system and the parallel-wire system by networks was carried out in this paper. The representation is given in terms of lumped parameters when the lengths of the carrier lines are short and it is given in terms of lumped and distributed parameters when the lengths of the carrier lines are long. 相似文献
55.
56.
Formulae are derived for the deflection surface of a symmetrically loaded circular plate having several points supports which are situated at equal distances apart on a single concentric circle. There is no restriction on the diameter of the support circle, which may be as large as the diameter of the plate itself. The results of this paper compare favorably with published experimental results. Numerical deflection coefficients for a uniformly loaded plate are provided, and these could be utilized for optimizing the positions and the number of concentrated supports. 相似文献
57.
Mary A. Anderson Frank Bowles C. O. Taiwo Jan D. Beckmann L. J. Lewis James R. Liesch Godfrey N. Brown H. L. Elvin Shib K. Mitra Richard F. Behrendt Graeme Kemelfield Hugh W. R. Hawes W. A. Dodd A. L. Tibawi 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1971,17(2):220-251
58.
A. D. C. Peterson Brian Holmes G. De Landsheere Helena W. F. Stellwag Oskar Anweiler J. O. J. Vanden Bossche Abraham Robinson F. I. Calvert H. H. Stern J. F. Willatt Sydney Taylor M. J. Langeveld M. A. Brimer T. N. Postlethwaite Alexandre Vexliard 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1964,10(1):106-126
59.
Sixten Marklund Franz Hilker Marjorie L. Jenkins Franklin Parker Gustav Jahoda M. J. Langeveld Karl Henrik Eriksson Nicholas Hans Gilbert de Landsheere Leslie D. Mclean J. Cambon A. St. Langeland S. Wiegersma Richard F. Goodings J. B. Biggs 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1966,12(2):221-251
60.