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We propose using five data-driven community detection approaches from social networks to partition the label space in the task of multi-label classification as an alternative to random partitioning into equal subsets as performed by RAkELd. We evaluate modularity-maximizing using fast greedy and leading eigenvector approximations, infomap, walktrap and label propagation algorithms. For this purpose, we propose to construct a label co-occurrence graph (both weighted and unweighted versions) ba...
Gleichwertige Lebensverhältnisse erfahren in der politischen Debatte zurzeit eine starke Aufmerksamkeit. Die CDU-CSU-SPD-geführten Bundesregierung hat in ihrem Koalitionsvertrag für die 19. Legislaturperiode die Einsetzung einer Kommission ‚Gleichwertige Lebensverhältnisse‘ beschlossen, die bis Mitte 2019 konkrete Vorschläge für eine Politik gleichwertiger Lebensverhältnisse erarbeiten soll. Dieses Vorhaben steht vor der Herausforderung, das Postulat gleichwertiger Lebensverhältnisse zunächst...
Electro-static discharge (ESD) event can cause upset or permanent damage of integrated circuits (IC) and electrical systems. The risk of ESD fails needs to be mitigated or prevented. ESD robustness of IC products and electrical systems is specified, verified and qualified according to respective ESD standards. For high-voltage IC products based on smart power semiconductor technologies for industrial, power and automotive applications, design of effective and cost-efficient ESD protection is ...
This thesis is devoted to the study of mass effects in higher order radiative corrections within QED and QCD. The first part of the thesis deals with the process of deep-inelastic scattering. We compute the full mass dependence of the pure singlet Wilson coefficient in the polarized and unploarized case to next-to-leading order using iterated integrals over square root valued letters. Through explicit expansion in the asymptotic limit we proof the factorization of the heavy Wilson coefficie...
Dieses Promotionsvorhaben zentriert die Frühe (Medien-)Bildung sowie die Forschungs- und Themengebiete Migration und Interkulturalität, die in der Kindheitsforschung generell und kulturvergleichenden Kindheitsforschung speziell bislang nicht hinreichend berücksichtigt wurden. Der Fokus der vorliegenden Qualifikationsarbeit, die im Rahmen des interventiv angelegten, in Dortmund angesiedelten, Forschungsprojekts KidSmart – Medienkompetent zum Schulübergang (2010-2012) entstanden ist (vgl....
Resting heart rate (RHR) is positively related with mortality. Regular exercise causes a reduction in RHR. The aim of the systematic review was to assess whether regular exercise or sports have an impact on the RHR in healthy subjects by taking different types of sports into account. A systematic literature research was conducted in six databases for the identification of controlled trials dealing with the effects of exercise or sports on the RHR in healthy subjects was performed. The studies...
In the field of surface engineering, the use of self-lubricous coatings with the incorporation of vanadium represent a promising approach to reduce friction, thus contributing to the wear behavior. For vanadium containing hard coatings produced by means of thin film technology, the reduction in friction at elevated temperatures was repeatedly attributed to temperature-induced and tribo-oxidatively formed oxides which act as solid lubricant. Only very few studies focused on the tribological ch...
Direct Behavior Rating (DBR) as a behavioral progress monitoring tool can be designed as longitudinal assessment with only short intervals between measurement points. The reliability of these instruments has been mostly evaluated in observational studies with small samples based on generalizability theory. However, for a standardized use in the pedagogical field, a larger and broader sample is required in order to assess measurement invariance between different participant groups and over tim...
Computer-based testing (CBT) is gaining importance for studies addressing the diagnosis of competencies, because it is possible to simulate authentic action situations and may reduce the effort of analyzing the data. This benefit is most important for the phase of item design. In this phase of assessment construction, the pattern of answers of a sample is used to draw conclusions on the functionality of the items. Currently, there are no standards for the encodement of items which consider th...
In the one-step manufacturing process for fiber metal laminate parts, the so-called in situ hybridization process, the fabrics are interacting with metal blanks. During deep drawing, the liquid matrix is injected between the metal sheets through the woven fiber layers. The metal blanks can be in contact with dry or with infiltrated fibers. The formability of the blanks is influenced by the variation of the starting time of injection. The reason for that is that, due to high contact forces, th...
Magnesium (Mg)-based biomaterials are promising candidates for bone and tissue regeneration. Alloying and surface modifications provide effective strategies for optimizing and tailoring their degradation kinetics. Nevertheless, biocompatibility analyses of Mg-based materials are challenging due to its special degradation mechanism with continuous hydrogen release. In this context, the hydrogen release and the related (micro-) milieu conditions pretend to strictly follow in vitro standards bas...
Das Innenrundschälschleifen mit galvanisch gebundenen CBN-Schleifscheiben ist ein hocheffizientes Fertigungsverfahren der Bohrungsbearbeitung von gehärteten Stählen. Durch hohe Schleifscheibengeschwindigkeiten können beim Innenrundschleifen hohe Zeitspanvolumina realisiert werden. Trotz seiner Vorzüge stellt das Verfahren aufgrund der komplexen Eingriffsverhältnisse eine große Herausforderung in seiner Prozessbeherrschung dar. Um die Vorteile des Verfahrens prozesssicher und wirtschaftlich e...
Blazars like Markarian 421 or Markarian 501 are active galactic nuclei (AGN), with their jets orientated towards the observer. They are among the brightest objects in the very high energy (VHE) gamma ray regime (>100 GeV). Their emitted gamma-ray fluxes are extremely variable, with changing activity levels on timescales between minutes, months, and even years. Several questions are part of the current research, such as the question of the emission regions or the engine of the AGN and the part...
Es wird ein enger Zusammenhang zwischen schulischem Erfolg und bildungssprachlichen Kompetenzen vermutet. Unzureichende Kompetenzen in diesem Bereich werden häufig als mögliche Erklärung für Disparitäten im Bildungserfolg bei Kindern unterschiedlicher Herkunft herangezogen. Um alle Kinder zu Bildungserfolg führen zu können, wurden sowohl international als auch in Deutschland verschiedene methodisch-didaktische Konzepte zur fachintegrierten Förderung bildungssprachlicher Kompetenzen entwickelt...
Ein Überleben von Organismen unter extremen Umweltbedingungen, wie beispielsweise hohe Drücke, hohe und tiefe Temperaturen oder extreme pH-Werte, ist nur durch das genaue Zusammenspiel verschiedener Faktoren möglich. Ein entscheidender Faktor für die Stabilität und Aktivität der Proteine ist die native dreidimensionale Proteinstruktur, die in der Aminosäuresequenz codiert ist. Die Stabilität von Proteinen gegenüber extremen Temperaturen und Drücken kann jedoch auch durch Osmolyte beeinflusst ...
Graphene-ferromagnet interfaces possess remarkable properties like induced magnetism in the graphene film, increased magnetic anisotropy in the ferromagnetic film, and chiral magnetism. Previously, the graphene-ferromagnet interface was investigated mainly on metallic substrates. Yet, silicon carbide (SiC) is a promising graphene substrate due to its semi-insulating properties and its industrial relevance. This thesis investigates for the first time the intercalation of thin cobalt films...
This thesis includes two parts presenting the results on the research on the deformation of ferrofluid-filled elastic capsules in external magnetic fields as well as on the possibility of the usage of swelling elastic disks as microswimmers by triggering hysteretic shape transformations. The first part is a primarily theoretical study of deformations and shape transitions of ferrofluid capsules induced by homogeneous and inhomogeneous magnetic fields. The thin elastic shell is modelled b...
In der vorliegenden Dissertation wird die Absicht verfolgt, eine Skizze zu den alltagsimmanenten Copingprozessen von Familien mit beeinträchtigten Kindern zu erstellen, in der die Betrachtung ihrer Anforderungen und Leistungen unter einem kontextsensiblen Fokus geschieht. Die Arbeit verfolgt dabei ein doppeltes Erkenntnisinteresse: zum einen wird ein bislang nicht tiefergehend verfolgter Betrachtungsschwerpunkt vorgeschlagen, um die Situation von Familien mit beeinträchtigten Kindern und der ...