Hausaufgaben im Sportunterricht : Neue Potenziale durch Apps und digitale Angebote?

Hausaufgaben können wie im restlichen Fächerkanon als notwendige Ergänzung zum Unterricht gesehen werden, sie werden allerdings im Lehr-Lern-Prozess nur selten eingesetzt. Der bisher meist nur vereinzelt vorhandene Anteil an Hausaufgaben im Sportunterricht könnte durch den Einsatz von digitalen Angeboten mehrwertbildend vergrößert werden. Dieser Artikel gibt daher eine Übersicht des Einsatzspektrums für digitale Angebote und deren alltagstauglichen Einsatz in der Umsetzung von Hausaufgaben. Hierfür werden verschiedene Kategorien von digitalenAngeboten beleuchtet und dabei Vor- und Nachteile sowie Grenzen der einzelnen Anwendungen herausgearbeitet. Die zur Verfügung stehenden Anwendungen können sehr viele verschiedene Facetten des Sportunterrichts abbilden, der jeweiligen Sportlehrkraft obliegt die differenzierte Auswahl der Werkzeuge. Für die Zukunft wären noch mehr spezifisch auf den Anwendungsfall Schule und die Anforderungen der Schüler* innen ausgerichtete Angebote wünschenswert, damit ein leichter und verständlicher Umgang auf hohem Datenschutzniveau zum (schul)(sportlichen) Alltag werden kann

The Catalyzing Role of FinTechs for Innovation Sourcing in Financial Services

In recent years a lively scene of startup companies developed focusing specifically on the financial services sector. These so-called FinTechs are characterized by highlyinnovative capacities, rapid development methods and a short time to market for their services and technical solutions. This external source of innovation can pose a competitive threat to traditional financial service companies or, on the contrary, may add value by serving as an additional resource for new ideas and technical solutions. Using a multiple case study approach, 18 interviews were conducted with representatives of FinTechs, financial services corporations, and specialized consulting firms. Westudy how large corporations and FinTechs interact with each other, what organizational setups were chosen and how knowledge transfer is organized for successful collaboration.Our results indicate that the organizational setup, split into three dimensions, has a strong impact on the integration of external knowledge which, in turn, affectsthe success of innovation sourcing

Abnehmendes Produktivitätswachstum – zunehmende Produktivitätsunterschiede

Wie in anderen Industriestaaten ist auch in Deutschland in den vergangenen Jahren trotz eines anhaltenden Wirtschaftswachstums, einer zurückgehenden Arbeitslosigkeit und einer hohen technologischen Dynamik ein Rückgang des Produktivitätswachstums zu beobachten. In einem Workshop Anfang 2018 in Berlin wurde dieses Phänomen eingehend diskutiert

Field assisted sintering of Ta–Al2_2O3_3 composite materials and investigation of electrical conductivity

Ta–Al$_2$O$_3$ composite samples with different compositions are prepared using Field Assisted Sintering Technique (FAST). Two different alumina powders are used to investigate the influence of the starting powders particle size on the microstructural features and the resulting electrical conductivity of the prepared composite materials. Percolation threshold of the two material systems is influenced by the metal fraction, as well as the alumina particle size of the starting powder. The percolation threshold for the fine- and the coarse-grained alumina is found to be at 15 vol.-% Ta and 7.5 vol.-% Ta, respectively. Microstructural investigations show significant differences in terms of particle shape of both, Ta and Al$_2$O$_3$ after sintering, most likely being the reason for the different percolation thresholds of the investigated materials. Anisotropy effects resulting from the processing using FAST and the influence on electrical properties are also shown

Field‐Assisted Sintering of Nb–Al2_2O3_3 Composite Materials and Investigation of Electrical Conductivity

Field-assisted sintering technique (FAST) is used for the preparation of Nb–Al$_2$O$_3$ composite materials. The electrical conductivity is investigated depending on the particle size of the used starting powders and under varying volume contents of the refractory metal in the starting powder mixture. The percolation threshold is investigated and found to be influenced not only by the metal fraction but also by the particle size of the alumina used for sample preparation. For the fine- and coarse-grained alumina, a percolation threshold of 17.5 and 10 vol% Nb is estimated, respectively. Furthermore, the microstructure is investigated to gain a basic understanding of the dependency between microstructural features and the resulting material properties on the macroscopic scale. Also, the influence of the sintering process and the resulting microstructure–properties relationship is considered. It could be shown that the electrical properties are anisotropic because of anisotropy effects caused by the FAST process

A sampling method for detecting buried objects using electromagnetic scattering

We consider a simple (but fully three-dimensional) mathematical model for the electromagnetic exploration of buried, perfect electrically conducting objects within the soil underground. Moving an electric device parallel to the ground at constant height in order to generate a magnetic field, we measure the induced magnetic field within the device, and factor the underlying mathematics into a product of three operations which correspond to the primary excitation, some kind of reflection on the surface of the buried object(s) and the corresponding secondary excitation, respectively. Using this factorization we are able to give a justification of the so-called sampling method from inverse scattering theory for this particular set-up

Microflares in accretion disks

We have investigated the phenomenon of explosive chromospheric evaporation from an accretion disk as a mechanism for fast variability in accreting sources such as low mass X-ray binaries and active galactic nuclei. This has been done in the context of advection dominated accretion flows, allowing both high and low states to be considered. This mechanism can in principle produce sub-millisecond timescales in binaries and sub-minute timescales in active galaxies. However, even considering the possibility that large numbers of these microflares may be present simultaneously, the power emitted from these microflares probably amounts to only a small fraction of the total X-ray luminosity.Comment: 5 pages, 1 figure, uses older A&A class file; accepted for publication in A&

Temperature-dependent recombination coefficients in InGaN light-emitting diodes : hole localization, Auger processes, and the green gap

We obtain temperature-dependent recombination coefficients by measuring the quantum efficiency and differential carrier lifetimes in the state-of-the-art InGaN light-emitting diodes. This allows us to gain insight into the physical processes limiting the quantum efficiency of such devices. In the green spectral range, the efficiency deteriorates, which we assign to a combination of diminishing electronhole wave function overlap and enhanced Auger processes, while a significant reduction in material quality with increased In content can be precluded. Here, we analyze and quantify the entire balance of all loss mechanisms and highlight the particular role of hole localization