RTP payload format for H.264/SVC scalable video coding

The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team‘s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC.Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL)and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, including the design criteria, use cases, signaling and payload structure.     

Getting real: the authenticity of remote labs and simulations for science learning

Teachers use remote labs and simulations to augment or even replace hands-on science learning. We compared undergraduate students’ experiences with a remote lab and a simulation to investigate beliefs about and learning from the interactions. Although learning occurred in both groups, students were more deeply engaged while performing the remote lab. Remote lab users felt and behaved as though they completed a real scientific experiment. We also examined whether realistic visualizations improved the psychological and learning experiences for each lab. Students who watched live video of the device collecting their data in the remote lab felt most engaged with the task, suggesting that it is the combination of the realistic lab and realistic video that was of the greatest benefit.     

Kulturelle Partizipation bei Jugendlichen als Feld der Person-Umwelt-Transaktion

What motivates adolescents to cultural participation? This question is important for the discourse on aesthetic education, in which cultural participation is regarded as contributing to the development of adolescents’ personality, values, and competencies. However, research on this issue suffers from fragmentation. Unconnected research on cultural participation from the sociology, cultural education, and differential psychology literature are reviewed, and it is shown how they may be supplemented using the theory of planned behaviour and integrated in a single theoretical framework. This framework centers on cultural participation as a field of person-environment transaction. Participation is regarded as being determined by both person and environmental variables and has the potential of changing these variables. On both its person and its environment sides, the model contains domain-specific determinants that mediate effects of the domain-general variables on which research on cultural participation has focused up to now. An overview of own empirical research related to the model is given and avenues for future research on cultural participation are discussed.     

Defensive transition in soccer – are prompt possession regains a measure of success? A quantitative analysis of German Fußball-Bundesliga 2010/2011

Abstract

The aim of the study was to evaluate the time required by German Bundesliga soccer teams to recover ball possession – which was operationalised as defensive reaction time – and identify both the differences between top teams and the rest of the league and the influence of match status on the aforementioned indicator. Therefore, teams were classified into 3 distinct groups according to their final league position: top, in-between and bottom. In total, all 306 games of the season 2010/2011 were analysed post-event. Top teams recovered ball possession quickest after losing it in comparison to the other groups and demonstrated lower defensive reaction times (approximately 1 s in each match status) compared to the remaining teams. Moreover, all groups showed the lowest defensive reaction times when trailing. The results of this study imply that recovering ball possession as quickly as possible after losing possession was an important determinant of successful defensive performance in German Bundesliga season 2010/2011. Further, the current score seemed to be highly influential on the defensive reaction time. The implications of the results for future research, especially considering opponent interactions, are critically discussed.     

Validation of a model and a simulator for road cycling on real tracks

In this study, methods for data acquisition, analysis, modelling, and simulation of performance parameters in road cycling on real tracks were developed and evaluated. A simulator was designed to facilitate the measurement in a laboratory environment. The simulation included real height profiles and a video playback that was synchronised with the cyclist’s current virtual position on the track, and online visualisation of course and performance parameters. Field data obtained on mountain tracks in this study were compared with the state-of-the-art mathematical model for road cycling power, established by Martin et al. (J Appl Biomech 14: 276–291, 1998), which accounts for the gradient force, air resistance, rolling resistance, frictional losses in wheel bearings and inertia. The model described the performance parameters accurately with correlation coefficients of 0.96–0.99 and signal-to-noise ratios of 19.7–23.9 dB. It was shown that the mathematical model could be implemented on an ergometer for simulating rides on real courses, providing similar quality measures when comparing field and simulator measurements.     

Video clips for YouTube: Collaborative video creation as an educational concept for knowledge acquisition and attitude change related to obesity stigmatization

Mobile phones and advanced web-based video tools have pushed forward new paradigms for using video in education: Today, students can readily create and broadcast their own digital videos for others and create entirely new patterns of video-based information structures for modern online-communities and multimedia environments. This paradigm shift in video usage can be used for advanced learning about complex topics in higher education, for example, learning about socio-scientific or medical topics. Yet–technology aside–applicable educational concepts using collaborative video creation as a method need to be developed. In the present study, we investigate a specific concept designed to fight obesity stigmatization by developing knowledge using a learning-through-design-approach. We expected that creating videos can actually contribute to a deeper understanding of obesity and to a reduction in stigmatizing attitudes–when compared to a control condition. Dependent measures were based on the students’ video products, obesity-related knowledge and attitudes. The course group assessed their own knowledge on causes of obesity and stigmatization because of obesity higher in the post-test than a control group who read a newspaper article on the topic. A corresponding significant reduction in stigmatizing attitudes was found. In sum, results indicate significant differences between students who produced YouTube videos and a control group of students. The results are interpreted as a confirmation of our initial assumptions and evidence indicating that the program is successfully applicable in higher education.     

A constructivist approach in a blended e-learning environment for statistics

In this study, we report on the students' evaluation of a self-constructed constructivist e-learning environment for statistics, the compendium platform (CP). The system was built to endorse deeper learning with the incorporation of statistical reproducibility and peer review practices. The deployment of the CP, with interactive workshops and group assignments, immerses students in a novel blended e-learning experience. Based on the Delone and McLean framework, we tested an explanatory success model with a sample of 607 business students, collected during three consecutive academic years. The results indicate that system quality and teacher support are the most important success factors, directly or indirectly contributing to a higher degree of relative advantage and satisfaction, both of which strongly determine continuous intention to use. The findings ascertain the usability and acceptance of the CP and promote a more radical constructivist approach to the teaching of statistics, but also other subjects.     

The consequences of central examinations on educational quality standards and labour market outcomes

Central examinations—that is, centrally set and marked exams—have often been discussed as an instrument for improving educational outcomes. The aim of our study was to determine whether central exams have an impact not only on educational but also on labour market outcomes. We explain school quality choice through the incentives created by central exams vs. non‐central exams and model the resulting students’ schooling decisions and employers’ wage decisions. We use the German Abitur and the variation among the German federal states with respect to central exams as a quasi‐experimental design for alternative educational quality regimes. As hypothesised from our theoretical analysis, the percentage of Abitur holders increases more quickly in quality regimes without central exams than with central exams. However, as theoretically expected in the case of a pooled labour market, the wage premium decreases not only for Abitur‐holders without central exams but also for all Abitur‐holders. This is due to the quality deterioration in the states without central exams which spills over into a pooled labour market. Thus, graduates from states with central exams and higher educational standards ‘pay’ for the quality deterioration of educational standards in states without central exams.