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91.
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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
93.
The radial and axial motions of electrons in the betatron are described by means of a potential function of forces. Previously reported conditions of equilibrium, stability and damping of oscillations are derived for the region of parabolic variation of the potential. Extension of the analysis to, non-parabolic regions gives an account of the injection in conventional instruments in better agreement with experiment, particularly in regard to higher voltages of injection.Space charge limitations are discussed with the help of the Laplacian of the potential of forces.By means of an additional radial electric field electrons can be introduced as in the magnetron, without any asymmetry inherent in the conventional betatron circumferential injector. The analysis of the conditions of equilibrium and stability, greatly facilitated in this case by the notion of potential, shows that no substantial improvement in space charge limitations can be expected and that the required variations between the flux linking the electron orbits and the magnetic and electric fields at the orbits are difficult to realize on account of their complexity and narrow tolerances. The X-ray output of a small experimental double yoke instrument was measured by a phototube multiplier viewing an irradiated fluorescent screen and gave evidence of multiple group electron capture. 相似文献
94.
This study assessed the differential contribution of personality to the explanation of variance in achievement in the mother tongue and mathematics at the high school level. The results indicated that personality, as measured by the HSPQ, aided the explication of variance in achievement in the mother tongue significantly, but had little influence on mathematics. Personality contributed as much to the explanation of variance in the mother tongue as did the composite cognitive variable. The influence of personality on achievement in mathematics was shown to be negligible. Some practical implications for the teaching of the first language are drawn. 相似文献
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96.
Claartje L. Ter Hoeven Ward van Zoonen Kathryn L. Fonner 《Communication monographs》2016,83(2):239-263
Technological advancements in the workplace frequently have produced contradictory effects by facilitating accessibility and efficiency while increasing interruptions and unpredictability. We combine insights from organizational paradoxes and the job demands–resources model to construct a framework identifying positive and negative mechanisms in the relationship between communication technology use (CTU) and employee well-being, operationalized as work engagement and burnout. In this study of Dutch workers, we demonstrate that CTU increases well-being through positive pathways (accessibility and efficiency) and decreases well-being through negative pathways (interruptions and unpredictability). We highlight the importance of (1) investigating CTU resources and demands simultaneously to grasp the relationship between CTU and employee well-being, and (2) considering CTU's downsides to successfully implement new communication technologies and flexible work designs. 相似文献
97.
The WWW is increasingly used as a medium to support education and training. A course at the University of Twente in which groups of students collaborate in the design and production of multimedia instructional materials has now been supported by a website since 1995. Workflow was integrated with other components in the website to investigate whether workflow can help instructors and students to have a better overview of group progress. Our evaluation shows that the introduction of workflow does provide added value. Another outcome of the experiment is that the transfer of a business application (workflow) into the educational domain has highlighted some differences and similarities between educational and business processes. This article explores some of these issues as highlighted by the application of workflow in education. 相似文献
98.
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Andreas Bauer Jan Romberg Bernhard Sch?tz 《Informatik - Forschung und Entwicklung》2005,49(3):194-205
Zur Beherrschung der komplexen vernetzten und verteilten Funktionen von Automotive-Software ist eine Beschreibung des zu erstellenden
Systems auf verschiedenen Abstraktionsebenen und schrittweise überg?nge zwischen diesen Ebenen notwendig. Neben der Definition
geeigneter Ebenen werden zur Unterstützung echtzeitkritischer Systemanteile ein einheitliches Berechnungsmodell, ebenenspezifische
Beschreibungstechniken, sowie methodische Regeln für diese Abstraktionsebenen eingeführt und in den Werkzeugprototypen AutoFocus integriert. 相似文献
100.