Maxwell–Schrödinger System: Well-Posedness and Standing Waves

In dieser Arbeit untersuchen wir das Maxwell-Schrödinger System im Ganzraum mit einer Potenznichtlinearität. Wir zeigen eine umfassende lokale Wohlgestelltheitstheorie in geeigneten Räumen oberhalb des Energieraums, die Existenz, Eindeutigkeit, stetige Abhängigkeit und Erhaltungsgrößen der Lösungen des Cauchyproblems umfasst. Außerdem untersuchen wir die Lösbarkeit von verwandten dispersiven Gleichungen in $U^p$- und $V^p$-Räumen. Schließlich zeigen wir noch die Nichtexistenz von stehenden Wellen mit einer milden Abfallbedingung im Maxwell-Schrödinger System ohne Potenznichtlinearität

Weak Invariants of Actions of the Automorphism Group of a Graph

Automorphism groups of graphs may lead to multiple equivalent solutions of graph-clustering algorithms and to a certain degree of arbitrariness in selecting one or more solution(s) as well as to problems with partition comparison measures. Knowledge of the automorphism group is crucial for stability analysis, for evaluating the degree of arbitrariness involved in selecting a solution, as well as for a further classification as congruent solutions or structurally equivalent solutions. For this purpose we identify three weak invariants of group actions of the automorphism group of a graph, namely modularity, partition type, and the Kolmogorov-Sinai entropy. In particular, we extend the Kolmogorov-Sinai entropy for measuring the uncertainty in finite permutation groups and we apply the underlying construction for testing if multiple structurally equivalent solutions exist for a given graph partition

Recent Advances in Modularity Optimization and Their Application in Retailing

In this contribution we report on three recent advances in modularity optimization, namely: 1. The randomized greedy (RG) family of modularity optimization algorithms are state-of-the-art graph clustering algorithms which are near optimal, fast, and scalable. 2. The extension of the RG family to multi-level clustering. 3. A new entropy based cluster index which allows the detection of the proper clustering levels and of stable core clusters at each level. Last, but not least, several marketing applications of these algorithms for customer enablement and empowerment are discussed: e.g. the detection of low-level cluster structures from retail purchase data, the analysis of the co-usage structure of scientific documents for detecting multilevel category structures for scientific libraries, and the analysis of social groups from the friend relation of social network sites

Archives of Data Science, Series A. Vol. 1,1: Special Issue: Selected Papers of the 3rd German-Polish Symposium on Data Analysis and Applications

The first volume of Archives of Data Science, Series A is a special issue of a selection of contributions which have been originally presented at the {\em 3rd Bilateral German-Polish Symposium on Data Analysis and Its Applications} (GPSDAA 2013). All selected papers fit into the emerging field of data science consisting of the mathematical sciences (computer science, mathematics, operations research, and statistics) and an application domain (e.g. marketing, biology, economics, engineering)

Improving the First Impression of an Online Scientific Publishing Service: A Usability Test

A study of the Human-Oriented Technology Lab at Carleton University shows that users form an opinion (first impression) regarding a new website in 50 milliseconds (Lindgaard et al (2006)). Furthermore, the Halo effect causes that the first impression will be transferred on the whole organization. For this reason, it is very important to optimize a website before one starts with marketing activities. There is no thing as a second first impression. In this contribution, we analyse the website of a new scientific journal. The usability test covers 2 areas: The layout and the functionality of the website on a variety of devices (mobile devices (Android, iOS), Macs, PCs with different browsers)

Virtual Notes:Annotations on the WWW for Learning Environments

This paper describes Virtual Notes, small yellow stickers which can be freely placed on instrumented HTML-pages using standard Internet technology. In a teaching and research environment they provide a user- friendly and flexible way of improving collaboration by annotations, feedback, post-its and blackboards

Verhaltensbasierte Empfehlungsdienste für wissenschaftliche Bibliotheken und Bibliotheksverbünde

Märkte, Informationswirtschaft und -management, Wirtschaftswissenschaftliche Fakultät Wissenschaftliche Bibliotheken sind ein potentielles, neues Anwendungsfeld für vollautomatisierte, verhaltensbasierte Recommenderdienste. Wissenschaftliche Bibliotheken können leicht zu kundenzentrierten Serviceportalen im Stil von amazon.com weiterentwickelt werden. Studenten, Universitätslehrer und -forscher können mittel solcher Empfehlungsdienste ihren Anteil an den Transaktionskosten (z. B. Such- und Bewertungskosten für Informationsprodukte) reduzieren. Für Bibliothekare liegt der Vorteil in einer Verbesserung der Kundenberatung durch Empfehlungen und einer zusätzlichen Unterstützung bei der Marktforschung, Produktbewertung und dem Bestandsmanagement. In diesem Vortrag zeigen wir, wie verhaltensbasierte, verteilte Recommenderdienste in bestehende Bibliothekssysteme und -verbünde mit minimalem Aufwand integriert werden können und berichten über unsere Erfahrungen bei der Einführung eines solchen Dienstes an der Universitätsbibliothek der Universität Karlsruhe (TH)

Report on the First Working Group Meeting of the “AG Marketing”

This contribution reports on the first meeting of the new formed working group “Data Analysis and Classification in Marketing (AG Marketing)” of the data science society (GfKl) held at the KIT, Karlsruhe, November 14th – 15th, 2019. The abstracts of the presentations given reflect the ongoing trend to exploit a large variety of digital data sources for marketing purposes and the need for advanced and innovative analysis methods