TY - GEN AU - Althaus, Maike ID - 12079 TI - Share at all Costs? Ein Literaturüberblick zur Privacy Risk Calculus Theory ER - TY - GEN AU - Rohde, Lukas ID - 10203 TI - Sozioökonomische Implikationen des Sharing Economy Trends ER - TY - GEN AU - Bentfeld, Bastian ID - 15026 TI - Reputation in der Sharing Economy - Eine ökonometrische Analyse des Zusammenhangs zwischen Online-Bewertungen und Nachfrage am Beispiel von Airbnb ER - TY - GEN AU - Agethen, Christopher Heinrich ID - 10038 TI - Stoppt das Sharing? Ökonometrische Untersuchungen zur gesetzlichen Einschränkung von Airbnb ER - TY - GEN AU - Wegener, Moritz ID - 11959 TI - It's a match! - Entwicklung eines Ansatzes zur Identifikation von Cross-Listings auf Airbnb und TripAdvisor ER - TY - GEN AU - Gerzen, Gabriele ID - 13449 TI - Do Online Ratings Matter in the Sharing Economy? Analyzing the Impact of Online Ratings on Demand on Airbnb ER - TY - GEN AU - Resch, Tim ID - 14987 TI - Möglichkeiten und Grenzen crowdbasierter Ideenbewertung - Ein systematischer Literaturüberblick ER - TY - GEN AU - Milder, Christoph ID - 13748 TI - Externe Stimuli zur Geschäftsmodell-Ideengenerierung: Ein Experimenteller Ansatz ER - TY - CHAP AU - Karsten, Andrea ED - Wymann, Christian ID - 32157 T2 - Praxishandbuch Schreibdidaktik. Übungen zur Vermittlung wissenschaftlicher Schreibkompetenzen TI - Blätterwald zur Positionierung in akademischen Texten ER - TY - JOUR AB - RbInSe2 is attracting growing interest as a secondary semiconductor compound in Cu(In,Ga)Se2-based solar cells by virtue of the recent investigations on absorber post-deposition treatments with alkali metal salts that have resulted in significant efficiency improvements. However, the detection of the RbInSe2 phase on the surface of chalcopyrite absorbers is very challenging due to its nanometric thickness and the limited information available about its fundamental properties. In this context, this work expounds a detailed analysis of the vibrational properties of RbInSe2 that combines first-principle calculations with multiwavelength Raman scattering spectroscopy and provides a methodology for the detection and identification of very thin layers of this material employing solely optical measurements. As a result, here, we present the classification of the different vibrational modes together with the fingerprint Raman spectra of RbInSe2 thin films measured under five different excitations (close to and far from resonance). The employment of a 442 nm excitation wavelength is found to be the most adequate strategy for the detection and characterization of the RbInSe2 phase in view of its resonance with the band gap of the material and its low penetration depth. Additionally, the purity of the deposited thin films as well as the possible influence of the subjacent layers on the Raman spectra of the compound are also investigated by analyzing the presence of secondary phases and by measuring RbInSe2 thin films deposited onto Mo-coated soda-lime glass, respectively. These results set the basis for the future evaluation of the suitability of Raman spectroscopy as a fast and nondestructive characterization technique for the reliable identification and characterization of the nanometric layers of RbInSe2 in Cu(In,Ga)Se2-based solar cells. AU - Guc, Maxim AU - Kodalle, Tim AU - Kormath Madam Raghupathy, Ramya AU - Mirhosseini, Hossein AU - Kühne, Thomas AU - Becerril-Romero, Ignacio AU - Pérez-Rodríguez, Alejandro AU - Kaufmann, Christian A. AU - Izquierdo-Roca, Victor ID - 15723 JF - The Journal of Physical Chemistry C SN - 1932-7447 TI - Vibrational Properties of RbInSe2: Raman Scattering Spectroscopy and First-Principle Calculations ER - TY - JOUR AB - The behavior of alkali atom point defects in polycrystalline CuInSe2 is studied. In this work, three grain boundary models, one coherent twin boundary and two twin boundaries with dislocation cores, are considered. Total energy calculations show that all alkali metals tend to segregate at the grain boundaries. In addition, the segregation of alkali atoms is more pronounced at the grain boundaries with the dislocation cores. The diffusion of alkali metals along and near grain boundaries is studied as well. The results show that the diffusion of alkali atoms in the grain boundary models is faster than within the bulk. In addition, the ion exchange between Na and Rb atoms at the grain boundaries leads to the Rb enrichment at the grain boundaries and the increase of the Na concentration in the bulk. While the effects of Na and Rb point defects on the electronic structure of the grain boundary with the anion-core dislocation are similar, Rb atoms passivate the grain boundary with the cation-core dislocation more effectively than Na. This can explain the further improvement of the solar cell performance after the RbF-postdeposition treatment. AU - Chugh, Manjusha AU - Kühne, Thomas D. AU - Mirhosseini, Hossein ID - 13230 IS - 16 JF - ACS Applied Materials & Interfaces TI - Diffusion of Alkali Metals in Polycrystalline CuInSe2 and Their Role in the Passivation of Grain Boundaries VL - 11 ER - TY - JOUR AB - The behavior of alkali atom point defects in polycrystalline CuInSe2 is studied. In this work, three grain boundary models, one coherent twin boundary and two twin boundaries with dislocation cores, are considered. Total energy calculations show that all alkali metals tend to segregate at the grain boundaries. In addition, the segregation of alkali atoms is more pronounced at the grain boundaries with the dislocation cores. The diffusion of alkali metals along and near grain boundaries is studied as well. The results show that the diffusion of alkali atoms in the grain boundary models is faster than within the bulk. In addition, the ion exchange between Na and Rb atoms at the grain boundaries leads to the Rb enrichment at the grain boundaries and the increase of the Na concentration in the bulk. While the effects of Na and Rb point defects on the electronic structure of the grain boundary with the anion-core dislocation are similar, Rb atoms passivate the grain boundary with the cation-core dislocation more effectively than Na. This can explain the further improvement of the solar cell performance after the RbF-postdeposition treatment. AU - Chugh, Manjusha AU - Kühne, Thomas AU - Mirhosseini, S. Hossein ID - 15726 JF - ACS Applied Materials & Interfaces SN - 1944-8244 TI - Diffusion of Alkali Metals in Polycrystalline CuInSe2 and Their Role in the Passivation of Grain Boundaries ER - TY - JOUR AB - Adaptive kinetic Monte Carlo simulation (aKMC) is employed to study the dynamics and the diffusion of point defects in the CuInSe2 lattice. The aKMC results show that lighter alkali atoms can diffuse into the CuInSe2 grains, whereas the diffusion of heavier alkali atoms is limited to the Cu-poor region of the absorber. The key difference between the diffusion of lighter and heavier alkali elements is the energy barrier of the ion exchange between alkali interstitial atoms and Cu. For lighter alkali atoms like Na, the interstitial diffusion and the ion-exchange mechanism have comparable energy barriers. Therefore, Na interstitial atoms can diffuse into the grains and replace Cu atoms in the CuInSe2 lattice. In contrast to Na, the ion-exchange mechanism occurs spontaneously for heavier alkali atoms like Rb and the further diffusion of these atoms depends on the availability of Cu vacancies. The outdiffusion of alkali substitutional atoms from the grains results in the formation of Cu vacancies which in turn increases the hole concentration in the absorber. In this respect, Na is more efficient than Rb due to the higher concentration of Na substitutional defects in the CuInSe2 grains. AU - Kormath Madam Raghupathy, Ramya AU - Kühne, Thomas AU - Henkelman, Graeme AU - Mirhosseini, Hossein ID - 15725 JF - Advanced Theory and Simulations SN - 2513-0390 TI - Alkali Atoms Diffusion Mechanism in CuInSe 2 Explained by Kinetic Monte Carlo Simulations ER - TY - CONF AB - Artificial intelligence (AI) has the potential for far-reaching – in our opinion – irreversible changes. They range from effects on the individual and society to new societal and social issues. The question arises as to how students can learn the basic functioning of AI systems, what areas of life and society are affected by these and – most important – how their own lives are affected by these changes. Therefore, we are developing and evaluating school materials for the German ”Science Year AI”. It can be used for students of all school types from the seventh grade upwards and will be distributed to about 2000 schools in autumn with the support of the Federal Ministry of Education and Research. The material deals with the following aspects of AI: Discussing everyday experiences with AI, how does machine learning work, historical development of AI concepts, difference between man and machine, future distribution of roles between man and machine, in which AI world do we want to live and how much AI would we like to have in our lives. Through an accompanying evaluation, high quality of the technical content and didactic preparation is achieved in order to guarantee the long-term applicability in the teaching context in the different age groups and school types. In this paper, we describe the current state of the material development, the challenges arising, and the results of tests with different classes to date. We also present first ideas for evaluating the results. AU - Schlichtig, Michael AU - Opel, Simone Anna AU - Budde, Lea AU - Schulte, Carsten ED - Jasutė, Eglė ED - Pozdniakov, Sergei ID - 15332 KW - Artificial Intelligence KW - Machine Learning KW - Teaching Material KW - Societal Aspects KW - Ethics. Social Aspects KW - Science Year KW - Simulation Game SN - 978-9925-553-27-3 T2 - ISSEP 2019 - 12th International conference on informatics in schools: Situation, evaluation and perspectives, Local Proceedings TI - Understanding Artificial Intelligence – A Project for the Development of Comprehensive Teaching Material VL - 12 ER - TY - CONF AU - Opel, Simone Anna AU - Schlichtig, Michael AU - Schulte, Carsten AU - Biehler, Rolf AU - Frischemeier, Daniel AU - Podworny, Susanne AU - Wassong, Thomas ID - 15640 T2 - INFOS TI - Entwicklung und Reflexion einer Unterrichtssequenz zum Maschinellen Lernen als Aspekt von Data Science in der Sekundarstufe II VL - P-288 ER - TY - CONF AU - Schlichtig, Michael AU - Opel, Simone Anna AU - Schulte, Carsten AU - Biehler, Rolf AU - Frischemeier, Daniel AU - Podworny, Susanne AU - Wassong, Thomas ID - 15641 T2 - INFOS TI - Maschinelles Lernen im Unterricht mit Jupyter Notebook VL - P-288 ER - TY - CONF AU - Opel, Simone Anna AU - Schlichtig, Michael AU - Schulte, Carsten ID - 15643 T2 - WiPSCE TI - Developing Teaching Materials on Artificial Intelligence by Using a Simulation Game (Work in Progress) ER - TY - GEN AU - Tönsing, Johanna ID - 32431 T2 - Grundschulunterricht Deutsch 3 (2019) TI - Daniel Napp: Das schlaue Buch vom Büchermachen ER - TY - JOUR AU - Mäck, Markus AU - Caylak, Ismail AU - Edler, Philipp AU - Freitag, Steffen AU - Hanss, Michael AU - Mahnken, Rolf AU - Meschke, Günther AU - Penner, Eduard ID - 19300 JF - GAMM-Mitteilungen SN - 0936-7195 TI - Optimization with constraints considering polymorphic uncertainties ER - TY - JOUR AU - Sun, Jingjiang AU - Rust, Tarik AU - Kuckling, Dirk ID - 30926 IS - 22 JF - Macromolecular Rapid Communications KW - Materials Chemistry KW - Polymers and Plastics KW - Organic Chemistry SN - 1022-1336 TI - Light‐Responsive Serinol‐Based Polyurethane Nanocarrier for Controlled Drug Release VL - 40 ER -