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31.
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.  相似文献   
32.
ABSTRACT

The objective of this study was to create a valid, self-reported, game-specific soccer competence scale. A structural model of perceived competence, performance measures and motivation was tested as the basis for the scale. A total of 1321 soccer players (261 females, 1060 males) ranging from 12 to 15 years (13.4 ± 1.0 years) participated in the study. They completed the Perceived Game-Specific Soccer Competence Scale (PGSSCS), self-assessments of tactical skills and motivation, as well as technical and speed and agility tests. Results of factor analyses, tests of internal consistency and correlations between PGSSCS subscales, performance measures and motivation supported the reliability and validity of the PGSSCS. The scale can be considered a suitable instrument to assess perceived game-specific competence among young soccer players.  相似文献   
33.
Cultural Studies of Science Education - The link between science education and early childhood education is still blurred. This is so because many science education researchers apparently, but...  相似文献   
34.
How does classroom interaction support students’ apprenticeship into the ways of speaking, writing, and diagramming that constitute the practice of mathematics? We address this problem through an interpretative analysis of a whole-group conversation about alternative ways of solving a problem involving percent discounts that occurred in a sixth grade classroom. This research study draws upon Dewey’s theory of inquiry, Vygotsky’s cultural–historical psychology, Freudenthal’s realistic mathematics education, and Halliday’s systemic functional linguistics (SFL). From Freudenthal, we borrow the notions of mathematizing and guided reinvention—the former notion offers a view of mathematics as an activity of structuring subject matter and the latter one provides insights into the processes whereby mathematizing is learned and taught in the classroom. We glean from Dewey his view of reflective thinking as inquiry and the role that conversations may serve therein. We rely upon Vygotsky’s notions of a verbal thinking plane and a social phase of learning in order to reconsider the function of whole-class interaction in apprenticing students into mathematizing. Finally, SFL provides us with tools for explaining the choices of grammar and vocabulary students and teachers make as they realize meanings in whole-group conversations. Treating the selected whole-class conversation as a text, we focus our analysis on how this text came to mean what it did. Our central questions are as follows: What meanings were realized in the whole-class conversation by teacher and students and how were these meanings realized? How did the teacher’s lexico-grammatical choices guide the students’ choices? In addressing these questions, we advance an interpretation of the conversation as paradigmatic of students and teacher thinking aloud together about percents.  相似文献   
35.
Inhibitory control, the ability to restrain a prepotent but ineffective response in a given context, is thought to be indicative of a species’ cognitive abilities. This ability ranges from “basic” motoric self-regulation to more complex abilities such as self-control. During the current study, we investigated the motoric self-regulatory abilities of 30 pet dogs using four well-established cognitive tasks – the A-not-B Bucket task, the Cylinder task, the Detour task, and the A-not-B Barrier task – administered in a consistent context. One main goal of the study was to determine whether the individual-level performance would correlate across tasks, supporting that these tasks measure similar components of motoric self-regulation. Dogs in our study were quite successful during tasks requiring them to detour around transparent barriers (i.e., the Cylinder and Detour tasks), but were less successful with tasks requiring the production of a new response (i.e., A-not-B Bucket and A-not-B Barrier tasks). However, individual dog performance did not correlate across tasks, suggesting these well-established tasks likely measure different inhibitory control abilities, or are strongly influenced by differential task demands. Our results also suggest other aspects such as perseveration or properties of the apparatus may need to be carefully examined in order to better understand canine motoric self-regulation or inhibitory control more generally.  相似文献   
36.
In fast-paced and knowledge-intensive environments, licensing partnerships can be powerful levers for market expansion. Research on the management of technology-oriented licenses has nonetheless pointed out the risks of corrosive disputes caused by conflicting interests or misunderstandings among licensing partners. The choice made ex ante on mechanisms for resolving potential disputes is of prime importance in the execution of licensing exchanges. Although the legal literature has widely emphasized the advantages of arbitration towards litigation, public ordering remains the “default” option in managers’ eyes. By adopting a transaction cost economics logic, our study explores the conditions under which licensing partners may prefer arbitration over public ordering during the contractual-design phase. In accordance with our theoretical arguments, findings show that the occurrence of arbitration provisions increases when the coordination orientation adopted by licensing partners is extensive. In situations where both monitoring and coordination orientations are simultaneously extensive, results reveal a greater propensity to prefer arbitration over public ordering. Our research therefore supports the view that corporate decision-makers tend to favor the conciliatory stance and compromising awards typically associated with arbitration, only when exchanges are expected to be highly coordinative. Their preference for arbitration over litigation is magnified when the coordination orientation develops alongside the monitoring orientation.  相似文献   
37.
Our work concerns the design of robust information retrieval environments that can successfully handle queries containing misspelled words. Our aim is to perform a comparative analysis of the efficacy of two possible strategies that can be adopted.  相似文献   
38.
This paper proposes a new sliding mode observer for fault reconstruction, applicable for a class of linear parameter varying (LPV) systems. Observer schemes for actuator and sensor fault reconstruction are presented. For the actuator fault reconstruction scheme, a virtual system comprising the system matrix and a fixed input distribution matrix is used for the design of the observer. The fixed input distribution matrix is instrumental in simplifying the synthesis procedure to create the observer gains to ensure a stable closed-loop reduced order sliding motion. The ‘output error injection signals’ from the observer are used as the basis for reconstructing the fault signals. For the sensor fault observer design, augmenting the LPV system with a filtered version of the faulty measurements allows the sensor fault reconstruction problem to be posed as an actuator fault reconstruction scenario. Simulation tests based on a high-fidelity nonlinear model of a transport aircraft have been used to demonstrate the proposed actuator and sensor FDI schemes. The simulation results show their efficacy.  相似文献   
39.
Over the last few years, information and communication technologies have become an essential part of daily life, affecting education, employment, and leisure, among other activities. Nonetheless, many individuals still reap few or no benefits from these technologies, and there are resilient gaps in their use. Within this larger context, the authors examine the Internet digital divide between people with and without disabilities from a multidimensional approach. Rather than analyzing the gap in terms of “haves” and “have-nots,” a range of Internet-related dimensions—affordability, motivation and attitudes, skills, usage, and others—is taken into account.  相似文献   
40.
This study aimed to examine the reliability of different power and velocity variables during the Smith machine bench press (BP) and bench press throw (BPT) exercises. Twenty-two healthy men conducted four testing sessions after a preliminary BP one-repetition maximum (1RM) test. In a counterbalanced order, participants performed two sessions of BP in one week and two sessions of BPT in another week. Mean propulsive power, peak power, mean propulsive velocity, and peak velocity at each tenth percentile (20–70% of 1RM) were recorded by a linear transducer. The within-participants coefficient of variation (CV) was higher for the load–power relationship compared to the load–velocity relationship in both the BP (5.3% vs. 4.1%; CV ratio = 1.29) and BPT (4.7% vs. 3.4%; CV ratio = 1.38). Mean propulsive variables showed lower reliability than peak variables in both the BP (5.4% vs. 4.0%, CV ratio = 1.35) and BPT (4.8% vs. 3.3%, CV ratio = 1.45). All variables were deemed reliable, with the peak velocity demonstrating the lowest within-participants CV. Based upon these findings, the peak velocity should be chosen for the accurate assessment of BP and BPT performance.  相似文献   
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