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1.
Markus Keidl Alfons Kemper Donald Kossmann und Alexander Kreutz 《Informatik - Forschung und Entwicklung》2002,17(3):123-134
Zusammenfassung. Wir pr?sentieren in dieser Arbeit das ObjectGlobe-System, ein offenes und verteiltes Anfragebearbeitungssystem auf Internet-Datenquellen.
ObjectGlobe erweitert die begrenzten F?higkeiten des Internets bezüglich Anfragebearbeitung, indem es einen offenen Marktplatz
schafft, in dem eine Vielzahl von Anbietern Rechenzeit, Daten und Anfrageoperatoren bereitstellen. Den Schwerpunkt dieses
Beitrags bildet die im Rahmen des ObjectGlobe-Projekts entwickelte Metadatenverwaltung MDV, ein verteiltes Metadaten-Management-System.
Es besitzt eine 3-schichtige Architektur und unterstützt Caching und Replikation in der Mittelschicht, so dass Anfragen lokal
ausgewertet werden k?nnen. Benutzer spezifizieren die Informationen, die sie ben?tigen und die repliziert werden, mit Hilfe
einer besonderen Regelsprache. Um Replikate aktuell zu halten und die Replikation von neuen und relevanten Informationen anzusto?en,
verwendet das MDV-System einen neuartigen Publish & Subscribe-Algorithmus. Wir beschreiben diesen Algorithmus im Detail und
zeigen, wie er mit Hilfe eines normalen relationalen Datenbanksystems implementiert werden kann.
Eingegangen am 19. November 2001 / Angenommen am 30. Juli 2002 相似文献
2.
Dolores A. Stegelin Denise Anderson Karen Kemper Jennifer Wagner Katharine Evans 《Early Childhood Education Journal》2014,42(2):133-142
The purpose of this research project was to gain a greater understanding of daily routines of 4–7 year olds regarding physical activity and nutrition practices in typical early learning environments. The settings selected for this observational study included Head Start, primary, and after-school learning environments in a city in the southeast. Specifically, this exploratory study focused on the research question: What are typical daily physical activity and nutrition patterns in community-based early learning settings for young children 4–7 years of age in the United States? Two overarching themes were identified through data analysis: restriction of activity and restriction of physical movement. Results indicated that children in elementary school settings had fewer opportunities for indoor and outdoor physical activity than children in other settings and that children seek to be physically active and will do so when given the opportunity. Increasing time for both structured and unstructured physical activity and play for children ages 4–7 in early learning settings was recommended by the researchers. 相似文献
3.
Bortz Whitney Wall Gautam Aakash Tatar Deborah Lipscomb Kemper 《Journal of Science Education and Technology》2020,29(1):121-136
Journal of Science Education and Technology - Integrating computational thinking (CT) and science education is complex, and assessing the resulting learning gains even more so. Arguments that... 相似文献
4.
High antenatal maternal anxiety is related to ADHD symptoms, externalizing problems, and anxiety in 8- and 9-year-olds 总被引：8，自引：0，他引：8
Associations between antenatal maternal anxiety, measured with the State Trait Anxiety Inventory, and disorders in 8- and 9-year-olds were studied prospectively in 71 normal mothers and their 72 firstborns. Clinical scales were completed by the mother, the child, the teacher, and an external observer. Hierarchical multiple regression analyses showed that maternal state anxiety during pregnancy explained 22%, 15%, and 9% of the variance in cross-situational attention deficit hyperactivity disorder symptoms, externalizing problems, and self-report anxiety, respectively, even after controlling for child's gender, parents' educational level, smoking during pregnancy, birth weight, and postnatal maternal anxiety. Anxiety at 12 to 22 weeks postmenstrual age turned out to be a significant independent predictor whereas anxiety at 32 to 40 weeks was not. Results are consistent with a fetal programming hypothesis. 相似文献
5.
Wassenberg R Feron FJ Kessels AG Hendriksen JG Kalff AC Kroes M Hurks PP Beeren M Jolles J Vles JS 《Child development》2005,76(5):1092-1103
The relation between cognitive and motor performance was studied in a sample of 378 children aged 5-6. Half of these children had no behavior problems; the others were selected for externalizing (38%) or internalizing problems (12%). Quantitative and qualitative aspects of motor performance were related to several aspects of cognition, after controlling for the influence of attention. No relation between global aspects of cognitive and motor performance was found. Specific positive relations were found between both aspects of motor performance, visual motor integration and working memory, and between quantitative aspects of motor performance and fluency. These findings reveal interesting parallels between normal cognitive and motor development in 5- to 6-year-old children that cannot be ascribed to attention processes. 相似文献
6.
The Internal Working Model of the Self, Attachment, and Competence in Five-Year-Olds 总被引：5，自引：0，他引：5
The present studies examine some of the correlates of the self in the lives of young children. In Study 1, the connection is tested between young children's internal working model of self and their competence, social acceptance, behavioral adjustment, and behavioral manifestations of self-esteem. Ninety-five kindergartners aged between 51 and 76 months ( M age = 5 years, 3 months) participated in the study. An adapted version of the Puppet Interview was used to assess the representation of self. Affective quality (positiveness) of self and openness to admit imperfections were rated independently. Results show significant and positive relations of the positiveness of self with competence and social acceptance, with behavioral adjustment to school, and with behavioral manifestations of self-esteem, all rated by the teacher. In Study 2, Bowlby's assumption was tested that the working model of self is closely intertwined with the working model of attachment to mother. Subjects were 50 children aged between 55 months and 75 months ( M age = 5 years, 5 months). The working model of child-mother attachment was assessed through an Attachment Story Completion Task. The working model of self was measured via the Puppet Interview. Results show a positive and strong connection between the security of the child-mother attachment representation and the positiveness of self. The results of the two studies contribute to the validation of the adapted Puppet Interview. The Puppet Interview seems to be a promising instrument for assessing the representation of self in young children. 相似文献
7.
This study examined how Flesch Reading Ease and text cohesion affect older adults' comprehension of common health texts. All older adults benefited when high Flesh Reading Ease was combined with high cohesion. Older adults with small working memories had more difficulty understanding texts high in Flesch Reading Ease. Additionally, older adults with low verbal ability or older than 77 years of age had difficulty understanding texts high in text cohesion but low in Flesch Reading Ease. These results imply that writers must increase Flesch Reading Ease without disrupting text cohesion to ensure comprehension of health-related texts. 相似文献
8.
William W. Brickman Willy Strzelewicz William Taylor Joachim H. Knoll Mark Blaug Oskar Anweiler Andreas Fuchs Gilda L. de Romero Brest Alberto Aráoz Wolfgang Brezinka Enrique Oteiza W. F. Connell Robert J. Havighurst Daniel F. Wozniak Wolfgang Roth Karl Frey Alfons Otto Schorb 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1970,16(2):221-249
9.
Kyle R. Lynch Han C. G. Kemper Bruna Turi-Lynch Ricardo R. Agostinete Igor H. Ito Rafael Luiz-De-Marco 《Journal of sports sciences》2017,35(24):2421-2426
The objective of the present study was to investigate the effects of different sports on stress fractures among adolescents during a 9-month follow-up period. The sample was composed of 184 adolescents divided into three groups (impact sports [n = 102]; swimming [n = 35]; non-sports [n = 47]). The occurrence of stress fracture was reported by participants and coaches. As potential confounders we considered age, sex, resistance training, body composition variables and age at peak of height velocity. There were 13 adolescents who reported fractures during the 9-month period. Bone mineral density values were higher in adolescents engaged in impact sports (P-value = 0.002). Independently of confounders, the risk of stress fracture was lower in adolescents engaged in impact sports than in non-active adolescents (hazard ratio [HR] = 0.23 [95% confidence interval (CI) = 0.05 to 0.98]), while swimming practice was not associated to lower risk of fracture (HR = 0.49 [95% CI = 0.09 to 2.55]). In conclusion, the findings from this study indicate the importance of sports participation among adolescents in the reduction of stress fracture risk, especially with impact sports. More importantly, these results could be relevant for recognising adolescents in danger of not reaching their potential for peak bone mass and later an increased risk of fractures. 相似文献
10.
Acute impact of submaximal resistance exercise on immunological and hormonal parameters in young men 总被引：2，自引：0，他引：2
In this study, we examined the acute effects of submaximal resistance exercise on immunological and hormonal parameters in 7 resistance-trained and 10 non-resistance-trained males. The participants, who were aged 29.5 +/- 7.1 years (mean +/- s), performed submaximal resistance exercise at 75% of their one-repetition maximum. Blood samples were taken before, during, immediately after, and 30, 60 and 120 min after exercise and analysed for leukocyte subpopulations and stress hormones. Total leukocytes, neutrophils and monocytes increased during exercise, reaching their maximum 2 h after exercise. Lymphocytes increased during exercise, T-helper cells returned to resting values after exercise, and natural killer cells and T-suppressor cells decreased below resting values. The CD4/CD8 ratio decreased during exercise but increased during recovery. The resistance-trained participants tended to have lower T-helper cell counts before, during and immediately after exercise and a lower CD4/CD8 ratio during recovery than the non-resistance-trained participants. Plasma cortisol correlated positively with leukocytes during exercise (r = 0.572, P < 0.05), but negatively with T-helper cells 30 and 60 min after exercise (r = -0.573, P < 0.05; r = -0.642, P < 0.01, respectively). Our results indicate that resistance exercise leads to acute changes in leukocyte counts, despite moderate hormonal changes, independent of training status. Regular resistance exercise might lead to decreased T-helper cell counts and a lower CD4/CD8 ratio, which could increase susceptibility to infections. 相似文献