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761.
762.
Extending a recent study of the standards mothers apply in evaluating the quality of children's programs (Nikken et al., 1996), this study investigated the standards children between 9 and 12 years of age (N = 427) use to evaluate the quality of four types of children's programs: children's news programs, educational programs for children, dramatic programs for children, and cartoons. Data were collected by means of questionnaires. A factor analysis resulted in a list of nine types of quality standards. The two quality standards children considered most important were: (a) comprehensibility, and (b) aesthetic quality. Additional standards were: (c) entertainment, (d) involvement, (e) credibility, (f) innocuousness, (g) restfulness, (h) thought provocation, and (i) presence of role models. The importance children attached to the nine quality standards varied with both program type and child characteristics. Seven of the quality standards found in the present study are similar to the maternal quality standards observed in Nikken et al. ‘s study. The children in the present study generally viewed these seven quality standards as less important than the mothers in Nikken et al.’s study. However, the relative importance children and mothers attached to these quality standards showed similarity, especially in the case of cartoons, and to a lesser extent for children's news programs and dramatic programs. 相似文献
763.
764.
S. Arbanowski S. van der Meer S. Steglich und R. Popescu-Zeletin 《Informatik - Forschung und Entwicklung》2001,16(4):225-232
Zusammenfassung. Kommunikationsumgebungen und die damit verbundenen Datenverarbeitungsprozesse werden von Tag zu Tag komplexer. Nur der hochqualifizierte
Systemtechniker durchschaut noch die Prozesse, die sich hinter heutigen Kommunikationssystemen verstecken. Der Anwender bleibt
zunehmend auf der Strecke. Um diesem Prozess entgegenzuwirken, wurde am Lehrstuhl für Offene Kommunikationssysteme der TU
Berlin eine Plattform entwickelt, die „I-centric Communications” unterstützt. Die Plattform stellt bei der Bearbeitung von
Aufgaben nicht die Technik sondern Dienstpr?ferenzen der Benutzer in den Mittelpunkt. In diesem Papier werden die Idee „I-centric
Communications” und die entwickelte I-centric-Plattform vorgestellt. Auf Basis der entwickelten Plattform realisierte Anwendungen
und Dienste schlie?en das Papier ab.
Eingegangen am 30. Januar 2001 / Angenommen am 3. Juli 2001 相似文献
765.
Scott MA van der Kamp J Savelsbergh GJ Oudejans RR Davids K 《Research quarterly for exercise and sport》2004,75(2):130-137
We investigated how perturbing optical information affects the guidance of an unfolding hitting action. Using monocular and binocular vision, six participants were required to hit a rectangular foam object, released from two different heights, under four different approach conditions, two with object rotation (to perturb the viewed surface area) and two without. Participants made more misses under monocular conditions, and the presence of rotation had a significant effect on the duration between the arm's peak velocity and its contact with the object. We conclude that binocular information contributes to the timing of interceptive tasks. In addition, the guidance of interceptive actions does not appear to be based solely on object expansion information picked up from the viewed surface area. 相似文献
766.
Federico von Borstel 《Prospects》1992,22(3):263-271
having held various posts specializing in educational administration in different private institutions in California. Author of several articles dealing with the issue of productive work combined with academic study. 相似文献
767.
von Károlyi C 《Journal of learning disabilities》2001,34(4):380-391
It has often been conjectured that visual-spatial talents accompany dyslexia. But do individuals with dyslexia have unusual visual-spatial talents? Individuals with dyslexia were compared to controls on two computer-based visual-spatial tasks in two studies. In accordance with a diverging ability hypothesis, it was predicted that the dyslexia group would perform better on a global task, identifying impossible figures, and worse on a feature-oriented task, matching figures. These hypotheses were partially supported. On the global task, the dyslexia group was faster but no more accurate than the control group at identifying impossible objects. On the feature-oriented task, the control group outperformed the dyslexia group. The results indicate that the diverging ability hypothesis of dyslexia merits further investigation. 相似文献
768.
E. A. M. Heijnsdijk A. Pasdeloup A. J. van der Pijl J. Dankelman D. J. Gouma 《Annals of dyslexia》1968,50(1):980-985
Background: Due to the limited force feedback provided by laparoscopic instruments, surgeons may have difficulty in applying the appropriate force on the tissue. The aim of this study was to determine the influence of force feedback and visual feedback on the exerted pinch force. Methods: A grasper with a force sensor in the jaws was developed. Subjects with and without laparoscopic experience grasped and pulled pig bowel with a force of 5 N. The applied pinch force was measured during tasks of 1-s and 1-min duration. Visual feedback was provided in half the measurements. Force feedback was adjusted by changing the mechanical efficiency of the forceps from 30% to 90%. Results: The mean pinch force applied was 6.8 N (± 0.5), whereas the force to prevent slippage was 3.0 N ( ± 0.4). Improving the mechanical efficiency had no effect on the pinch force for the 1-s measurements. The amount of excessive pinch force when holding tissue for 1 min was lower at 30% mechanical efficiency compared with 90% (105% vs 131 %, p = 0.04). The tissue slipped more often when the subject had no visual feedback (2% vs 8%, p = 0.02). Conclusion: Force feedback and visual feedbacK playa more limited role than expected in the task of grasping tissue with laparoscopic forceps. 相似文献
769.
A directly applicable latent variable modeling procedure for classical item analysis is outlined. The method allows one to point and interval estimate item difficulty, item correlations, and item-total correlations for composites consisting of categorical items. The approach is readily employed in empirical research and as a by-product permits examining the latent structure of tentative versions of multiple-component measuring instruments. The discussed procedure is straightforwardly utilized with the increasingly popular latent variable modeling software Mplus, and is illustrated on a numerical example. 相似文献
770.
This article presents several longitudinal mediation models in the framework of latent growth curve modeling and provides a detailed account of how such models can be constructed. Logical and statistical challenges that might arise when such analyses are conducted are also discussed. Specifically, we discuss how the initial status (intercept) and change (slope) of the putative mediator variable can be appropriately included in the causal chain between the independent and dependent variables in longitudinal mediation models. We further address whether the slope of the dependent variable should be controlled for the dependent variable's intercept to improve the conceptual relevance of the mediation models. The models proposed are illustrated by analyzing a longitudinal data set. We conclude that for certain research questions in developmental science, a multiple mediation model where the dependent variable's slope is controlled for its intercept can be considered an adequate analytical model. However, such models also show several limitations. 相似文献