Editorial zum Themenheft ,,Automotive Software Engineering”

Ohne Zusammenfassung     

Lesetechniken für die Inspektion von Software-Anforderungsdokumenten Ein kontrolliertes Experiment zur Untersuchung der Effektivit?t und Verwendung von Zeit bei der Anwendung verschiedener Lesetechniken

Inspektion hilft bereits in frühen Phasen der Softwareentwicklung, die Qualit?t von Softwareprodukten zu bestimmen und Nachbearbeitungsaufwand einzusparen. Lesetechniken sind ein Ansatz, der die Aufmerksamkeit von Inspektoren beim individuellen Lesen auf bestimmte Fehlermengen lenken und dadurch die Arbeit mehrerer Inspektoren untereinander koordinieren soll. Diese Arbeit berichtet über ein Experiment, das einerseits die Effektivit?t und Effizienz mehrerer Lesetechniken auf individueller und auf Teamebene miteinander vergleicht und andererseits Zusammenh?nge der Verwendung von Lesezeit mit der Effektivit?t von bestimmten Inspektorengruppen untersucht.     

A proficiency model for pre-service physics teachers' pedagogical content knowledge (PCK)—What constitutes high-level PCK?

This study identifies proficiency levels in pre-service physics teachers' pedagogical content knowledge (PCK) and reveals how teacher education can promote transitions into higher proficiency. Teacher education plays a fundamental role in supporting pre-service teachers' PCK development. Proficiency levels are a powerful source when evaluating this PCK development because they characterize what learners are likely to be able to know on a specific level. Previous research has presented a model of proficiency levels in pre-service physics teachers' PCK; however, evidence for the model's validity is still lacking. According to the Refined Consensus Model of PCK, factors such as teachers' content knowledge (CK), their teaching experience, and their beliefs about teaching and learning science promote PCK development. Thus, understanding how and when pre-service physics teachers' CK, teaching experience, and beliefs contribute to their proficiency can bring insights into how teacher education can promote PCK development. To address this issue, N = 427 observations of pre-service physics teachers were analyzed. Utilizing the scale anchoring procedure, four different proficiency levels in pre-service physics teachers' PCK were identified. Analyzing these proficiency levels showed that lower levels can be characterized as remembering content-unspecific knowledge, whereas higher levels encompass content-specific strategies to structure and elaborate lessons. Additionally, logistic regression models revealed that pre-service physics teachers' CK is crucial for an increase in PCK proficiency. However, transitions into higher levels of PCK additionally require teaching experience and adequate beliefs about teaching and learning. Thus, our proficiency levels can be used to bring insights into how proficiency in PCK can be supported during teacher education. For example, teacher education should provide courses focusing on the science curriculum and the assessment of student learning to promote pre-service physics teachers' progression in PCK.     

Unsteady flow phenomena in human undulatory swimming: a numerical approach

The undulatory underwater sequence is one of the most important phases in competitive swimming. An understanding of the recurrent vortex dynamics around the human body and their generation could therefore be used to improve swimming techniques. In order to produce a dynamic model, we applied human joint kinematics to three-dimensional (3D) body scans of a female swimmer. The flow around this dynamic model was then calculated using computational fluid dynamics with the aid of moving 3D meshes. Evaluation of the numerical results delivered by the various motion cycles identified characteristic vortex structures for each of the cycles, which exhibited increasing intensity and drag influence. At maximum thrust, drag forces appear to be 12 times higher than those of a passive gliding swimmer. As far as we know, this is the first disclosure of vortex rings merging into vortex tubes in the wake after vortex recapturing. All unsteady structures were visualized using a modified Q-criterion also incorporated into our methods. At the very least, our approach is likely to be suited to further studies examining swimmers engaging in undulatory swimming during training or competition.     

Coaching performance and leadership behaviours in team sports

The aim of this study was to investigate coaching performance in team sports taking leadership behaviours into focus. To do so, coaching performance was put in a literature-based frame and analysed with reference to a task structure based on the idea of hierarchical planning. The focus of the paper is on a mixed methods multi-strand study using qualitative as well as quantitative threads to develop and verify a set of coaching strategies focussing on teambuilding and team leadership. Qualitative analyses showed that coaches do have a clear understanding of forming and leading a team, which could be shown by a specific set of strategies being used by high performance coaches from different team sports (basketball, football, handball, and volleyball). These strategies could be confirmed in a sequential quantitative study analysing coaches’ and players’ attitudes towards the previously analysed schemes. The results of this study are discussed in terms of methodical and practical implications.     

Regulation and deregulation in education policy: new reforms and school sports in Swedish upper secondary education

During the 1990s, neoliberal reforms in Sweden increased local school actors' possibilities to develop school profiles regarding both organization and content. This restructuring has increased the total number of school sports programs as well as the possibilities for upper secondary schools and sports clubs to develop elite and amateur sports on a local level. In a new educational reform, the Swedish Government criticizes parts of the Swedish school sports system. The Government believes that the majority of local school sports programs and courses obstruct the maintenance of national equivalence, that upper secondary schools use school sports to attract pupils for economic reasons and that some pupils involved in school sports may fail to reach the academic or vocational goals of regular upper secondary education. Using critical discourse analysis, the present paper illustrates how educational policies are linked to wider symbolic meaning systems in an attempt to legitimize, define and organize upper secondary schools and to characterize pupils as either eligible or ineligible to participate in school sports. The analyses are based on various types of empirical data: policy documents, official letters from the sports movement on the government bill and in-depth interviews. The results indicate that the reform represents a shift in the policy rhetoric: from a normative rhetoric highlighting pupils' social and emotional reasons for choosing school sports, to a rational rhetoric emphasizing efficiency, standardization and regulation of pupils' educational choices. Using school sports as an example, the paper shows how the main aim of the reform—to raise educational standards and maintain national equivalence—is achieved through social differentiation, meaning that pupils with the right performance indicators are selected for participation in programs to which they are suited.     

Adaptive progressive download based on the MPEG-4 file format

In this paper we describe how progressive download and adaptive streaming can be combined into a simple and efficient streaming framework. Based on the MPEG-4 file format (MP4) we use HTTP for transport and argue that these two components are sufficient for specifying an open streaming architecture. The client selects appropriate chunks from the MP4 file to be transferred based on (1) the header information (i.e. the "moov" box) in the first part of the file and (2) his observation of network throughput. The framework is completely client driven which allows for better server scalability and reduces signalling overhead. We discuss architecture and implementation issues such as complexity, interoperability and scalability and compare to 3GPP PSS Re1-6 adaptive streaming when appropriate. Measurements from a simple MP4/HTTP streaming client are presented showing that appropriate chunks are selected such that increased reliability is achieved.     

Authorship order

Considering the fact that authorship order plays such a significant role as a basis for scientific merit, this paper looks into the practices of authorship order from a research ethical perspective. We conclude that there is a wide variety of practices and no common understanding of what the different authorship positions signify. Authorship guidelines do not provide much help. We recognize that, regardless of what system for valuing authorship positions is used, it will be misleading and unfair in most applications because relative contributions vary in ways that are not captured by fixed value assignments to authorship positions. In theory, assigning percentage figures reflecting the relative contributions of the authors would solve that problem, but we argue that such a scheme is not likely to work in practice. It can also be questioned whether relative, rather than absolute, contributions should be the basis for scientific merit. Contributorship is discussed as an alternative, but is recognized to be insufficient both in communicating absolute and relative contributions, as standardly used. However, there may be a way forward with contributorship, but then, the level of detail needs to increase considerably and its application be standardized.     

Adaptive progressive download based on the MPEG-4 file format

In this paper we describe how progressive download and adaptive streaming can be combined into a simple and efficient streaming framework. Based on the MPEG-4 file format (MP4) we use HTTP for transport and argue that these two components are sufficient for specifying an open streaming architecture. The client selects appropriate chunks from the MP4 file to be transferred based on (1) the header information (i.e. the “moov” box) in the first part of the file and (2) his observation of network throughput. The framework is completely client driven which allows for better server scalability and reduces signalling overhead. We discuss architecture and implementation issues such as complexity, interoperability and scalability and compare to 3GPP PSS Rel-6 adaptive streaming when appropriate. Measurements from a simple MP4/HTTP streaming client are presented showing that appropriate chunks are selected such that increased reliability is achieved.     

The “manifest destiny” of the performing arts by A. Peacock

Journal of Cultural Economics -