@inproceedings{65446, author = {{Franke, Patrick and Lutters, Nicole and Riese, Julia and Kenig, Eugeny}}, location = {{Luzern (CH)}}, title = {{{Identification of multiple steady states in reactive absorption columns equipped with structured packings}}}, year = {{2026}}, } @inproceedings{65450, author = {{Breuing, Friederike and Daniel-Söltenfuß, Desiree and Kückmann, Marie-Ann}}, location = {{München}}, title = {{{Umgang mit (Um-)Brüchen – ein Normalzustand? Gestaltung von Innovationsprozessen aus Sicht des beruflichen Bildungspersonals}}}, year = {{2026}}, } @techreport{65426, abstract = {{In diesem Forschungsprojekt wurde ein Messverfahren zur Bestimmung akustischer Materialparameter von Polymeren im Ultraschallfrequenzbereich entwickelt. Das Verfahrens sollte, die üblichen standardisierten Prüfmethoden erweitern, die bislang primär im quasistatischen oder niederfrequenten Bereich eingesetzt wurden. Im Gegensatz zu bestehenden Verfahren wie dem Zeitstandversuch oder der Dynamisch Mechanischen Analyse (DMA) nach [DIN6721] sollte die neue Methode eine nicht-invasive Charakterisierung der (visko-)elastischen Materialparameter im Frequenzbereich von 0,75 MHz bis 2,5 MHz ermöglichen. Das entwickelte Ultraschallmesssystem arbeitet nach dem Puls Echo-Prinzip und kann eine räumlich segmentierte, ringförmige Anregung erzeugen. Die Bestimmung der frequenzabhängigen Materialparameter geschieht hierbei über ein inverses Verfahren. Die Ergebnisse des Projekts zeigen, dass die Segmentierung der Anregung, die Geometrie der Probe sowie das Puls-Echo-Messprinzip die Messergebnisse sowie die Sensitivität gegenüber Scherparametern wesentlich beeinflussen. Im Rahmen des Projektes wurde auch eine statistische Auswertung des Optimierungsverfahrens hinsichtlich transversal-isotroper Materialsymmetrie mit Rayleigh-Dämpfung durchgeführt. Die Ergebnisse zeigen, dass das entwickelte Verfahren gute Konvergenzeigenschaften aufweist und sich durch verbesserte Robustheit auszeichnet.}}, author = {{Dreiling, Dmitrij and Itner, Dominik and Birk, Carolin and Gravenkamp, Hauke and Henning, Bernd}}, keywords = {{Materialcharakterisierung, Polymer, Inverses Problem, Ultraschall, Optimierung}}, pages = {{12}}, publisher = {{Hannover : Technische Informationsbibliothek}}, title = {{{Vollständige Bestimmung der akustischen Materialparameter von Polymeren II}}}, doi = {{https://doi.org/10.34657/33602}}, year = {{2026}}, } @article{65456, author = {{Fuchs, Christian}}, issn = {{1933-1681}}, journal = {{Journal of Information Technology & Politics}}, pages = {{1--21}}, title = {{{What is Digital Democracy?}}}, doi = {{10.1080/19331681.2026.2660162}}, year = {{2026}}, } @article{65460, abstract = {{Beamsplitters represent fundamental components in both classical and quantum optical systems, enabling the distribution of light, as well as the generation of interference, superposition, and entanglement. However, optical networks constructed from conventional bulk 2 × 2-beamsplitters encounter inherent scalability issues, as the number of required beamsplitters scales quadratically with the number of optical modes for a fully connected network. Metasurfaces offer a promising route to overcome these constraints. By manipulating light at the wavelength scale, compact optical components with advanced functionalities can be constructed, which address several modes simultaneously. In this work, we design and experimentally utilize a metasurface as a multiport beamsplitter. Furthermore, we realized a multimode interferometer composed of two cascaded metasurfaces. We characterize the individual and cascaded metasurfaces by using classical light, showing controllable splitting ratios through tunable phase relations. We then expand the approach to quantum light, employing single photons to demonstrate second- and third-order photon correlations as well as single photon interference across multiple spatial paths. These results establish metasurface-based multiport beamsplitters as a scalable and reconfigurable platform bridging classical and quantum photonics. }}, author = {{Aschwanden, Rebecca and Claro-Rodríguez, Nicolás and Zhao, Ruizhe and Kallert, Patricia Anna Maria and Krieger, Tobias and Buchinger, Quirin and Covre da Silva, Saimon F. and Stroj, Sandra and Rota, Michele and Höfling, Sven and Huber-Loyola, Tobias and Rastelli, Armando and Trotta, Rinaldo and Huang, Lingling and Bartley, Tim and Jöns, Klaus and Zentgraf, Thomas}}, issn = {{2330-4022}}, journal = {{ACS Photonics}}, keywords = {{metasurface, beamsplitter, interferometer, quantum network, single photons, nanophotonics}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Cascaded Metasurface Interferometer for Multipath Interference with Classical and Quantum Light}}}, doi = {{10.1021/acsphotonics.6c00096}}, year = {{2026}}, } @article{65316, abstract = {{Metasurfaces are powerful tools for manipulating light using small structures on the nanoscale. In most metasurfaces, near-field couplings are treated as being unfavorable perturbations. Here, we experimentally investigate a structure consisting of sinusoidally modulated silicon waveguides where near-field coupling of local resonances leads to negative coupling, i.e., a negative coupling constant. This gives rise to wave-vector-dependent eigenstates of elliptical, linear, and circular polarizations. In particular, fully circular polarization states are not only present at a single point in momentum space (k-space) but also along a line. This circular polarization line, as well as a linear polarization line, emanates from a polarization degeneracy at the Dirac point. We experimentally validate the existence of these eigenstates and demonstrate the energy-, polarization-, and wave vector dependence of this metasurface as well as its sensitivity to fabrication tolerances. By tuning the incident k-vector, certain polarization-energy eigenstates are strongly reflected, allowing for uses in angle-tunable polarization filters and light sources.}}, author = {{Wetter, Helene and Wingenbach, Jan and Rehberg, Falk and Gao, Wenlong and Schumacher, Stefan and Zentgraf, Thomas}}, issn = {{2330-4022}}, journal = {{ACS Photonics}}, keywords = {{metasurface, waveguides, Dirac point, polarization, negative coupling}}, pages = {{2128--2133}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Polarization- and Wave-Vector Selective Optical Metasurface with Near-Field Coupling}}}, doi = {{10.1021/acsphotonics.5c02865}}, volume = {{13}}, year = {{2026}}, } @article{65458, author = {{Hamdoun, Ayoub and Mahnken, Rolf and Ostwald, Richard}}, journal = {{European Journal of Mechanics / A Solids}}, title = {{{A gradient-damage model for amorphous glassy polymers: Consistent formulation of viscoplasticity and damage evolution in a micromorphic framework}}}, doi = {{https://doi.org/10.1016/j.euromechsol.2026.106137}}, year = {{2026}}, } @inproceedings{61922, abstract = {{We present an extremely simple polynomial-space exponential-time $(1-\varepsilon)$-approximation algorithm for MAX-k-SAT that is (slightly) faster than the previous known polynomial-space $(1-\varepsilon)$-approximation algorithms by Hirsch (Discrete Applied Mathematics, 2003) and Escoffier, Paschos and Tourniaire (Theoretical Computer Science, 2014). Our algorithm repeatedly samples an assignment uniformly at random until finding an assignment that satisfies a large enough fraction of clauses. Surprisingly, we can show the efficiency of this simpler approach by proving that in any instance of MAX-k-SAT (or more generally any instance of MAXCSP), an exponential number of assignments satisfy a fraction of clauses close to the optimal value.}}, author = {{Buhrman, Harry and Gharibian, Sevag and Landau, Zeph and Gall, François Le and Schuch, Norbert and Tamaki, Suguru}}, booktitle = {{SIAM Symposium on Simplicity in Algorithms (SOSA)}}, pages = {{247--253}}, title = {{{A Simpler Exponential-Time Approximation Algorithm for MAX-k-SAT}}}, year = {{2026}}, } @article{65386, abstract = {{Abstract Risk is an integral part of modern societies and therefore school education, and in particular mathematics education, should develop students’ risk literacy. Students’ risk literacy is part of the interdisciplinary research project siMINT (Understanding complex STEM topics: Using simulations to promote competences for the 21st century). One first challenge in this project was to find a common ground for the inconsistently conceptualised terms of risk and risk literacy. Consequently, the aim of this paper is to contribute to the conceptualisation of risk and risk literacy. The first part of this paper provides a literature review on these areas, resulting in a working conceptualisation of the two concepts. We further carried out two consecutive steps of a Delphi study with N  = 15 and N  = 12 experts respectively, to develop a common conceptualisation based on the plurality of different dimensions and elements of risk and risk literacy. Based on the results of the first step of the Delphi study, we modified our working conceptualisation, using a common model of risk and risk literacy with different dimensions. In the second step of the Delphi study, the experts comment on (i) the dimensions and (ii) the elements of risk and risk literacy in these dimensions. The results showed that the experts are able to locate their individual definitions of risk in the model with three dimensions (relation between risk/uncertainty, connotation, and mathematical object) that we developed and to formulate reasons for their allocation. Furthermore, the results revealed that risk literacy consists of subsets of mathematical and non-mathematical elements that the experts rate differently with regard to their importance. In general, the results contribute to clarifying the constructs of risk and risk literacy as a basis for developing approaches to improve risk literacy. }}, author = {{Eichler, Andreas and Büchter, Theresa and Binder, Karin}}, issn = {{0173-5322}}, journal = {{Journal für Mathematik-Didaktik}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Conceptualising Risk and Risk Literacy—results of a Delphi Study Konzeptualisierung von Risiko und Risikokompetenz – Ergebnisse einer Delphi-Studie}}}, doi = {{10.1007/s13138-026-00268-0}}, volume = {{47}}, year = {{2026}}, } @article{64580, abstract = {{ There is a contradiction between seven meta-analyses, all of which indicate a substantial benefit of the flipped classroom (FC) method for K-12 teaching and some larger study that found no such benefit when compared to “traditional” teaching. In the theoretical part of the paper, we shed light on this contradiction by consulting general literature on meta-analyses. Ranking the 50 included FC studies by the number of classes per experimental condition, we found a negative correlation between the “size” of a study and the effect in favor of FC. In the empirical part, we present an FC study with three conditions concerning mathematical teaching, based on n  = 950 students aged 11–13, in which many relevant covariates (e.g., quality of instruction) were addressed. One FC condition was based on students’ knowledge acquisition through instructional videos at home (FCn: n  = 12 classes). Considering that self-regulation support might play a crucial role especially for young students working at home, another FC condition (FCS: n  = 12 classes) was implemented, in which students could learn additional math-free strategies concerning watching instructional videos. Both FC-conditions were experimentally compared with a control group of traditional teaching (TT: n  = 13 classes). No significant effect on learning gains was found between FCn and TT, indicating that “flipping” alone may not be more effective per se. However, a significant difference was found between FCS and FCn. Thus, supporting students’ self-regulation in addition may in indeed open the door to successful FC, even with very young students. }}, author = {{Wiesner, Patrick and Krauss, Stefan and Stegmüller, Nathalie and Binder, Karin}}, issn = {{2504-284X}}, journal = {{Frontiers in Education}}, publisher = {{Frontiers Media SA}}, title = {{{Is flipped classroom really superior?—Questioning the flip in K-12 teaching}}}, doi = {{10.3389/feduc.2026.1741733}}, volume = {{11}}, year = {{2026}}, } @proceedings{64797, editor = {{Birk, Lisa and Loth, Gerrit and Jotzo, Luca and Binder, Karin and Frischemeier, Daniel}}, location = {{Münster}}, publisher = {{International Association for Statistics Education}}, title = {{{14th IASE Satellite Conference "Statistics and Data Science Education in STEAM"}}}, doi = {{10.52041/iase25.158}}, year = {{2026}}, } @inproceedings{64581, author = {{Binder, Karin and Schnaitmann, Stephan and Erickson, Tim}}, booktitle = {{Proceedings of the IASE 2025 Satellite Conference - Statistics and Data Science Education in STEAM}}, editor = {{Birk, Lisa and Loth, Gerrit and Jotzo, Luca and Binder, Karin and Frischemeier, Daniel}}, publisher = {{International Association for Statistics Education}}, title = {{{Effects of a simulation-based training on students conceptual understanding of the Binomial test}}}, doi = {{10.52041/iase25.106}}, year = {{2026}}, } @inproceedings{64583, author = {{Büchter, Theresa and Binder, Karin and Eichler, Andreas}}, booktitle = {{Proceedings of the IASE 2025 Satellite Conference - Statistics and Data Science Education in STEAM}}, editor = {{Birk, Lisa and Loth, Gerrit and Jotzo, Luca and Binder, Karin and Frischemeier, Daniel}}, publisher = {{International Association for Statistics Education}}, title = {{{The integration of probability-based arguments in risk-related contexts}}}, doi = {{10.52041/iase25.125}}, year = {{2026}}, } @article{65465, author = {{Henschen, Patrick and Töpfer, Lew}}, journal = {{ffk Journal}}, number = {{11}}, pages = {{171–183}}, title = {{{Images of Climate Crises. Critical Remarks on Climate-Technical Imagery Production and the Possibilities of Desirable Futures}}}, doi = {{http://dx.doi.org/10.25969/mediarep/24633}}, year = {{2026}}, } @article{65476, abstract = {{Service research has evolved into an interdisciplinary research field that bridges diverse disciplines, including information systems (IS) and marketing. Nearly two decades ago, the service system concept was introduced as a foundational abstraction in service research, drawing on ideas from the service-dominant logic (S-D logic) of marketing. Despite its widespread adoption in service research, particularly in the IS discipline, the service system concept lacks a solid theoretical foundation. This has resulted in conceptual ambiguity and overlap with related constructs, such as service ecosystems. Moreover, it has largely remained a static analytical lens, insufficiently capturing dynamic service phenomena, including value co-creation and co-destruction, as well as the emergence of institutional arrangements. To address these limitations, we propose Luhmann’s systems theory (LST) as a robust framework for conceptualizing service systems as autopoietic (self-creating) systems, in which communication serves as the fundamental mechanism that drives value co-creation. We derive five theoretical propositions from this re-conceptualization that clarify conceptual ambiguity and allow researchers to explore dynamic service phenomena in greater depth. Given LST’s general approach, our conceptualization provides a theoretically grounded, interdisciplinary foundation for advancing service research.}}, author = {{Beverungen, Daniel and Poeppelbuss, Jens and Hemmrich, Simon and Iqbal, Taskeen}}, issn = {{1019-6781}}, journal = {{Electronic Markets}}, keywords = {{Service system, Service ecosystem, Systems theory, Service research}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Service through communication—Conceptualizing service systems with Luhmann’s systems theory}}}, doi = {{10.1007/s12525-026-00889-w}}, volume = {{36}}, year = {{2026}}, } @article{65480, abstract = {{Die Bonner Ethik-Erklärung/Über Künstliche Intelligenzen, Bildung und Subjektwerdung/Tagungsberichte}}, author = {{Reichenbach, Alexandra Maria and Jäde, Sylvia}}, issn = {{1436-1957}}, journal = {{ZSE (Zeitschrift für Soziologie der Erziehung und Sozialisation)}}, number = {{1}}, pages = {{114--117}}, publisher = {{Beltz Verlagsgruppe GmbH & Co. KG}}, title = {{{Erziehungswissenschaftliche Perspektiven auf Familie und ihre Öffentlichkeit(en). Bericht zur Tagung des Netzwerks Erziehungswissenschaftliche Familienforschung (EWIFF) „Familie und ihre Öffentlichkeit(en)“ von 7. bis 8. Juni an der Universität Erfurt.}}}, doi = {{10.3262/zse2601101}}, volume = {{46}}, year = {{2026}}, } @article{65481, author = {{Schönert, Kathrin and Sommer, Sabrina and Buhl, Heike M.}}, journal = {{Zeitschrift für Entwicklungspsychologie und Pädagogische Psychologie}}, publisher = {{Hogrefe}}, title = {{{Prädiktoren der persönlichen Verpflichtung in Eltern-Kind-Beziehungen im Erwachsenenalter}}}, doi = {{10.1026/0049-8637/a000315}}, year = {{2026}}, } @misc{65482, author = {{Hüwel, Fabian}}, title = {{{Untersuchung der Einflussfaktoren auf die Recyclingfähigkeit von flammgeschütztem Polyamid 12-Pulver beim selektiven Lasersintern (Studienarbeit)}}}, year = {{2026}}, } @article{65490, abstract = {{In recent years, nanostructures assembled by DNA have found promising applications in optics, medicine, and sensing. DNA origami in particular provides unique self‐assembly properties, not only enabling a vast variety of functionalization schemes but also presenting a promising route to fabricate large‐scale, bottom‐up nanostructured arrays. This approach has comparable precision to electron beam lithography but avoids slow and expensive patterning steps. However, self‐assembly of lattices with high order and well‐defined periodicity requires careful tuning of the deposition parameters and interactions involved, which has been done mostly on mica so far. As mica is not compatible with standard microfabrication processes, we investigate here the assembly of DNA origami lattices on the most general microfabrication material, that is, silicon wafers, which has turned out to be rather challenging. We study how the forming of polycrystalline 2D‐fishnet‐type lattices is influenced by different incubation conditions and strengths of the origami–origami and origami‐surface interactions, with the aim to create large‐scale single‐crystalline lattices. The lattices are characterized by atomic force microscopy and analyzed for precision of formation, achievable domain size, and surface coverage of well‐formed lattices. Thanks to the silicon substrate, these DNA origami lattices can be further combined with traditional microfabrication processes to turn them, for example, into metamaterials with novel optical properties.}}, author = {{Järvinen, Heini and Parikka, Johannes M. and Rajapaksha, R. P. Thiwangi N. and Keller, Adrian Clemens and Toppari, J. Jussi}}, issn = {{2688-4062}}, journal = {{Small Structures}}, number = {{4}}, publisher = {{Wiley}}, title = {{{Towards Single‐Crystalline DNA Origami Lattices on Silicon Wafers for Bottom‐Up Nanofabrication}}}, doi = {{10.1002/sstr.202500813}}, volume = {{7}}, year = {{2026}}, } @inproceedings{63918, abstract = {{Many real-world datasets, such as citation networks, social networks, and molecular structures, are naturally represented as heterogeneous graphs, where nodes belong to different types and have additional features. For example, in a citation network, nodes representing "Paper" or "Author" may include attributes like keywords or affiliations. A critical machine learning task on these graphs is node classification, which is useful for applications such as fake news detection, corporate risk assessment, and molecular property prediction. Although Heterogeneous Graph Neural Networks (HGNNs) perform well in these contexts, their predictions remain opaque. Existing post-hoc explanation methods lack support for actual node features beyond one-hot encoding of node type and often fail to generate realistic, faithful explanations. To address these gaps, we propose DiGNNExplainer, a model-level explanation approach that synthesizes heterogeneous graphs with realistic node features via discrete denoising diffusion. In particular, we generate realistic discrete features (e.g., bag-of-words features) using diffusion models within a discrete space, whereas previous approaches are limited to continuous spaces. We evaluate our approach on multiple datasets and show that DiGNNExplainer produces explanations that are realistic and faithful to the model's decision-making, outperforming state-of-the-art methods.}}, author = {{Das, Pallabee and Heindorf, Stefan}}, booktitle = {{Proceedings of the ACM Web Conference 2026 (WWW ’26)}}, location = {{Dubai, United Arab Emirates}}, publisher = {{ACM}}, title = {{{Discrete Diffusion-Based Model-Level Explanation of Heterogeneous GNNs with Node Features}}}, year = {{2026}}, }