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XAI for U: Explainable AI for Ubiquitous, Pervasive and Wearable Computing
Get PDFThe workshop XAI for U aims to address the critical need for transparency in Artificial Intelligence (AI) systems that integrate into our daily lives through mobile systems, wearables, and smart environments. Despite advances in AI, many of these systems remain opaque, making it difficult for users, developers, and stakeholders to verify their reliability and correctness. This workshop addresses the pressing need for enabling Explainable AI (XAI) tools within Ubiquitous and Wearable Computing and highlights the unique challenges that come with it, such as XAI that deals with time-series and multimodal data, XAI that explains interconnected machine learning (ML) components, and XAI that provides user-centered explanations. The workshop aims to foster collaboration among researchers in related domains, share recent advancements, address open challenges, and propose future research directions to improve the applicability and development of XAI in Ubiquitous Pervasive and Wearable Computing - and with that seeks to enhance user trust, understanding, interaction, and adoption, ensuring that AI- driven solutions are not only more explainable but also more aligned with ethical standards and user expectations
HyenaPixel: Global Image Context with Convolutions
Get PDFIn computer vision, a larger effective receptive field (ERF) is associated with better performance. While attention natively supports global context, its quadratic complexity limits its applicability to tasks that benefit from high-resolution input. In this work, we extend Hyena, a convolution-based attention replacement, from causal sequences to bidirectional data and two-dimensional image space. We scale Hyena’s convolution kernels beyond the feature map size, up to 191×191, to maximize ERF while maintaining sub-quadratic complexity in the number of pixels. We integrate our two-dimensional Hyena, HyenaPixel, and bidirectional Hyena into the MetaFormer framework. For image categorization, HyenaPixel and bidirectional Hyena achieve a competitive ImageNet-1k top-1 accuracy of 84.9% and 85.2%, respectively, with no additional training data, while outperforming other convolutional and large-kernel networks. Combining HyenaPixel with attention further improves accuracy. We attribute the success of bidirectional Hyena to learning the data-dependent geometric arrangement of pixels without a fixed neighborhood definition. Experimental results on downstream tasks suggest that HyenaPixel with large filters and a fixed neighborhood leads to better localization performance
Erste Änderungsordnung der Bachelor-Prüfungsordnung Technikjournalismus vom 23. März 2023 der Hochschule Bonn-Rhein-Sieg vom 26. September 2024
No full textIT for Future? Resource Consumption of Information Technology and Measures of Green IT
No full textThe Information and Communication Technology (ICT) sector is a significant global industry, and addressing climate change is of critical importance. This paper aims to assess the resources utilized by the ICT sector, the associated negative environmental impacts, and potential mitigation measures. In order to understand these aspects, this study attempts to categorize the resources used by ICT, analyze the amount consumed and the resulting negative impacts, and determine what measures exist to mitigate them. An economic and empirical evaluation shows a negative trend in ICT’s resource consumption, mainly due to increased energy consumption and rising carbon emissions from devices such as smartphones and data centers. The investigated countermeasures focus on Green IT strategies that encompass energy efficiency, carbon awareness, and hardware efficiency principles as outlined by the Green Software Foundation. Special attention is given to reducing the environmental footprint of data center operations and smartphones. This paper concludes that Green IT strategies, although promising in theory, are often not implemented at an industry level
Manufacturing of Blends based on Biopolyesters and Polylactides: Process-induced Structure and Properties
No full textProcess-induced changes in thermo-mechanical viscoelastic properties and the corresponding morphology of biodegradable polybutylene adipate terephthalate (PBAT) and polylactic acid (PLA) blown film blends modified with four multifunctional chain-extending cross-linkers (CECL) were investigated. The introduction of CECL modified the properties of the reference PBAT/PLA blend significantly. The thermal analysis showed that the chemical reactions were incomplete after compounding, and that film blowing extended them. SEM investigations of the fracture surfaces of blown extrusion films reveal the significant effect of CECL on the morphology formed during the processing. The anisotropic morphology introduced during film blowing proved to affect the degradation processes as well. Furthermore, the reactions of CECL with PBAT/PLA induced by the processing depend on the deformation directions. The blow-up ratio parameter was altered to investigate further process-induced changes proving synergy with mechanical and morphological features. Using blown film extrusion, the elongational behavior represents a very important characteristic. However, its evaluation may be quite often problematic, but with the SER Universal Testing Platform it was possible to determine changes in the duration of time intervals corresponding to the rupture of elongated samples
Is It Really You Who Forgot the Password? When Account Recovery Meets Risk-Based Authentication
No full textFunctionalized ionic liquid coatings in the Pd-catalyzed selective hydrogenation of acetylene in ethylene-rich feeds
No full textThis study explores the tuning of a Pd/Al2O3 hydrogenation catalyst for the selective removal of trace acetylene from ethylene-rich feeds by coating the catalyst with non-functionalized and functionalized ionic liquids (denoted as SCILL and Advanced SCILL materials, respectively). These materials were tested in an automated continuous hydrogenation rig converting 3300 ppm of acetylene in excess ethylene, a gas mixture mimicking a technical front-end steam cracker feed composition. While the sulfonic-acid-functionalized IL coating resulted in a highly active but very unselective catalyst converting mainly ethylene to ethane, an Advanced SCILL catalyst prepared from a nitrile-functionalized IL reduced the acetylene concentration down to less than 1 ppm, while leaving over 99% of the ethylene untouched. We also examined the potential transformations of the IL layer under reaction conditions by means of 1H NMR. Except for a ketone-functionalized IL, which was inherently labile, all tested ILs primarily underwent C2-ethylation or remained unaltered. Our findings highlight the great potential of functionalized ILs in modifying heterogeneous hydrogenation catalysts
Encapsulation of reactive, chiral-nematic liquid crystals using coaxial electrospinning for optical gas sensing
No full textIn der vorliegenden Arbeit werden die nematischen Flüssigkristallgemische (E7 und E8) zum Zwecke der Gassensorik mit einer reaktiven, optisch aktiven Substanz dotiert. Die Dotierung verursacht die Ausbildung einer chiral-nematischen Phase, die einen eindimensionalen photonischen Kristall mit Reflexionsmaxima im sichtbaren Bereich des elektromagnetischen Spektrums erzeugt. Infolge einer chemischen Reaktion des Dotiermittels mit dem einem Analyten, ändert sich mit seiner chemischen Zusammensetzung auch dessen helical twisting power (HTP). Diese Änderung verursacht eine Verschiebung des reflektierten Wellenlängenbereichs, was als Änderung der farblichen Erscheinung mit dem bloßen Auge wahrgenommen werden kann. In dieser Arbeit wird das koaxiale Elektrospinnen verwendet, um Flüssigkristalle in Polymerfasern von wenigen Mikrometern Durchmesser einzukapseln. Der Vergleich zwischen eingekapseltem und nicht eingekapseltem dotierten Flüssigkristall wird mit einer dafür entwickelten Reaktionskammer UV/VIS-spektroskopisch durchgeführt. Die ablaufenden Reaktionen werden mittels FTIR-Spektroskopie untersucht. Die Fasern und die verwendeten Flüssigkristalle werden lichtmikroskopisch charakterisiert. Es werden zusätzlich Möglichkeiten untersucht die Wasserbeständigkeit der hergestellten Fasern zu verbessern, um ihre Eignung für künftige technische Anwendungen zu steigern. Hierzu wird das triaxiale Elektrospinnen verwendet, um die Fasern mit einer zusätzlichen wasserbeständigen Polymerhülle zu überziehen. Es wird zudem die Möglichkeit untersucht koaxial gesponnene Fasern nachträglich zu vernetzen, um so eine Wasserfestigkeit zu erzielen.In this work, nematic liquid crystal mixtures (E7 and E8) are doped with a reactive, optically active substance for gas sensing purposes. The doping induces the formation of a chiral-nematic phase, which acts as a one-dimensional photonic crystal with reflection maxima in the visible range of the electromagnetic spectrum. As a result of a chemical reaction of the dopant with an analyte, its helical twisting power (HTP) changes with its chemical composition. This change causes a shift in the reflected wavelength range, which can be perceived as a change in color appearance with the naked eye. In this work, coaxial electrospinning is used to encapsulate liquid crystals in polymer fibers with diameters of a few micrometers. A comparison between encapsulated and non-encapsulated doped liquid crystal is conducted using a specially developed reaction chamber for UV/VIS spectroscopy. The ongoing reactions are investigated using FTIR spectroscopy. The fibers and the liquid crystals used are characterized using light microscopy. Additionally, the possibilities of improving the water resistance of the produced fibers to enhance their suitability for future technical applications are explored. For this purpose, triaxial electrospinning is used to coat the fibers with an additional water-resistant polymer shell. The possibility of cross-linking coaxially spun fibers post-production to achieve water resistance is also investigated
Development of an active-site titrant for SARS-CoV-2 main protease as an indispensable tool for evaluating enzyme kinetics
No full textA titrant for the SARS-CoV-2 main protease (Mpro) was developed that enables, for the first time, the exact determination of the concentration of the enzymatically active Mpro by active-site titration. The covalent binding mode of the tetrapeptidic titrant was elucidated by the determination of the crystal structure of the enzyme–titrant complex. Four fluorogenic substrates of Mpro, including a prototypical, internally quenched Dabcyl-EDANS peptide, were compared in terms of solubility under typical assay conditions. By exploiting the new titrant, key kinetic parameters for the Mpro-catalyzed cleavage of these substrates were determined