TY - BOOK A1 - Schmitt, Joachim T1 - Ethik und Akzeptanz BT - Notizen zum Fachgespräch am 25. Februar 2021 an der Technischen Hochschule Aschaffenburg N2 - Die Vorträge der Referenten des Fachgesprächs "Ethik und Akzeptanz" vom 25. Februar sind in dieser Broschüre von Joachim Schmitt zusammengefasst. Zitiert werden: Prof. Dr. Georg Rainer Hofmann, Dr. Stefan Ullrich, Otto Obert, Ulrich Wilmsmann und Prof. Dr. Dominik Herrmann. KW - Digitalethik KW - KI KW - Ethik KW - Akzeptanz KW - Digitalisierung KW - Ethik KW - Akzeptanz Y1 - 2021 UR - https://www.mainproject.eu/studien SN - 978-3-9818442-6-9 VL - 2021 PB - IMI-Verlag CY - Aschaffenburg ER - TY - RPRT A1 - Schmitt, Joachim A1 - Schumacher, Meike A1 - Leimeister, Katja T1 - Wissenstransfer und Weiterbildung N2 - Die AutorInnen fassen in dieser Broschüre die Beiträge der ReferentInnen beim Symposium von Wirtschaft und Hochschule am 11. März 2021 an der TH Aschaffenburg zusammen. Daneben werden auch die Ergebnisse aus den Workshops zur Learning Persona dargestellt. KW - Weiterbildung KW - Wissenstransfer KW - Berufliche Fortbildung KW - Wissenschaftstransfer Y1 - 2021 UR - https://www.mainproject.eu/studien ER - TY - CHAP A1 - Schneegans, Jan A1 - Eilbrecht, Jan A1 - Zernetsch, Stefan A1 - Bieshaar, Maarten A1 - Doll, Konrad A1 - Stursberg, Olaf A1 - Sick, Bernhard T1 - Probabilistic VRU Trajectory Forecasting for Model-Predictive Planning A Case Study: Overtaking Cyclists T2 - 2021 IEEE Intelligent Vehicles Symposium Workshops (IV Workshops) KW - Fahrerassistenzsystem KW - Radfahrer KW - Autonomes Fahrzeug Y1 - 2021 U6 - https://doi.org/10.1109/IVWorkshops54471.2021.9669208 SP - 272 EP - 279 PB - IEEE ER - TY - CHAP A1 - Zernetsch, Stefan A1 - Trupp, Oliver A1 - Kress, Viktor A1 - Doll, Konrad A1 - Sick, Bernhard T1 - Cyclist Trajectory Forecasts by Incorporation of Multi-View Video Information T2 - 2021 IEEE International Smart Cities Conference (ISC2) KW - Autonomes Fahrzeug KW - Radfahrer Y1 - 2021 U6 - https://doi.org/10.1109/ISC253183.2021.9562857 SP - 1 EP - 7 PB - IEEE ER - TY - CHAP A1 - Bieshaar, Maarten A1 - Zernetsch, Stefan A1 - Riepe, Katharina A1 - Doll, Konrad A1 - Sick, Bernhard T1 - Cyclist Motion State Forecasting - Going beyond Detection T2 - 2021 IEEE Symposium Series on Computational Intelligence (SSCI) KW - Autonomes Fahrzeug KW - Radfahrer Y1 - 2021 U6 - https://doi.org/10.1109/SSCI50451.2021.9660151 SP - 1 EP - 8 PB - IEEE ER - TY - CHAP A1 - Diwersy, Bettina A1 - Schulze-Krüdener, Jörgen T1 - Kinder und Jugendliche mit Behinderung sind in erster Linie Kinder und Jugendliche T2 - Droit et Handicap dans la Grande Région – De l'enfance à l'âge adulte, état des lieux KW - Kind KW - Jugend KW - Behinderung Y1 - 2021 SP - 189 EP - 248 PB - Publications des travaux de recherches menées au CJFA, Université de la Sarre. Editions Juridiques Fran-co-Allemandes CY - Saarbrücken ER - TY - JOUR A1 - Diwersy, Bettina T1 - Transnationalen Kinderschutz optimieren – Vieles könnte getan werden JF - Nachrichtendient NDV KW - Transnationalisierung KW - Kinderschutz Y1 - 2021 VL - 100 IS - 10 SP - 491 EP - 496 ER - TY - JOUR A1 - Diwersy, Bettina A1 - Schulze-Krüdener, Jörgen T1 - Transnationaler Kinderschutz in der Großregion – Entwicklungen und Perspektiven JF - DZI – Fachzeitschrift Soziale Arbeit KW - Transnationalisierung KW - Kinderschutz KW - Großregion Y1 - 2021 VL - 2021 IS - 2 SP - 48 EP - 55 ER - TY - JOUR A1 - Diwersy, Bettina T1 - Professionelle Grenzarbeit im transnationalen Kinderschutz: Sie kann gelingen, wenn… JF - Blickpunkt Jugendhilfe KW - Jugendhilfe KW - Kinderschutz Y1 - 2021 VL - 26 IS - 1 SP - 11 EP - 15 ER - TY - CHAP A1 - Hetzel, Manuel A1 - Reichert, Hannes A1 - Doll, Konrad A1 - Sick, Bernhard T1 - Smart Infrastructure: A Research Junction T2 - 2021 IEEE International Smart Cities Conference (ISC2) KW - Autonomes Fahrzeug KW - Kreuzung Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1109/ISC253183.2021.9562809 SP - 1 EP - 4 PB - IEEE ER - TY - CHAP A1 - Reichert, Hannes A1 - Lang, Lukas A1 - Rosch, Kevin A1 - Bogdoll, Daniel A1 - Doll, Konrad A1 - Sick, Bernhard A1 - Rellss, Hans-Christian A1 - Stiller, Christoph A1 - Zollner, J. Marius T1 - Towards Sensor Data Abstraction of Autonomous Vehicle Perception Systems T2 - 2021 IEEE International Smart Cities Conference (ISC2) KW - Autonomes Fahrzeug Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1109/ISC253183.2021.9562912 SP - 1 EP - 4 PB - IEEE ER - TY - CHAP A1 - Hausmann, Michael A1 - Neitzel, Charlotte A1 - Hahn, Hannes A1 - Winter, Ruth A1 - Falkova, Iva A1 - Heermann, Dieter W. A1 - Pilarczyk, Götz A1 - Hildenbrand, Georg A1 - Scherthan, Harry A1 - Falk, Martin T1 - Space and Time in the Universe of the Cell Nucleus after Ionizing Radiation Attacks: A Comparison of Cancer and Non-Cancer Cell Response T2 - The 1st International Electronic Conference on Cancers: Exploiting Cancer Vulnerability by Targeting the DNA Damage Response KW - Krebszelle KW - Strahlentherapie KW - Zellkern Y1 - 2021 U6 - https://doi.org/https://doi.org/10.3390/IECC2021-09219 PB - MDPI CY - Basel Switzerland ER - TY - JOUR A1 - Hausmann, Michael A1 - Falk, Martin A1 - Neitzel, Charlotte A1 - Hofmann, Andreas A1 - Biswas, Abin A1 - Gier, Theresa A1 - Falkova, Iva A1 - Heermann, Dieter W. A1 - Hildenbrand, Georg T1 - Elucidation of the Clustered Nano-Architecture of Radiation-Induced DNA Damage Sites and Surrounding Chromatin in Cancer Cells: A Single Molecule Localization Microscopy Approach JF - International Journal of Molecular Sciences N2 - In cancer therapy, the application of (fractionated) harsh radiation treatment is state of the art for many types of tumors. However, ionizing radiation is a “double-edged sword”—it can kill the tumor but can also promote the selection of radioresistant tumor cell clones or even initiate carcinogenesis in the normal irradiated tissue. Individualized radiotherapy would reduce these risks and boost the treatment, but its development requires a deep understanding of DNA damage and repair processes and the corresponding control mechanisms. DNA double strand breaks (DSBs) and their repair play a critical role in the cellular response to radiation. In previous years, it has become apparent that, beyond genetic and epigenetic determinants, the structural aspects of damaged chromatin (i.e., not only of DSBs themselves but also of the whole damage-surrounding chromatin domains) form another layer of complex DSB regulation. In the present article, we summarize the application of super-resolution single molecule localization microscopy (SMLM) for investigations of these structural aspects with emphasis on the relationship between the nano-architecture of radiation-induced repair foci (IRIFs), represented here by γH2AX foci, and their chromatin environment. Using irradiated HeLa cell cultures as an example, we show repair-dependent rearrangements of damaged chromatin and analyze the architecture of γH2AX repair clusters according to topological similarities. Although HeLa cells are known to have highly aberrant genomes, the topological similarity of γH2AX was high, indicating a functional, presumptively genome type-independent relevance of structural aspects in DSB repair. Remarkably, nano-scaled chromatin rearrangements during repair depended both on the chromatin domain type and the treatment. Based on these results, we demonstrate how the nano-architecture and topology of IRIFs and chromatin can be determined, point to the methodological relevance of SMLM, and discuss the consequences of the observed phenomena for the DSB repair network regulation or, for instance, radiation treatment outcomes. KW - Krebszelle KW - Strahlentherapie Y1 - 2021 U6 - https://doi.org/https://doi.org/10.3390/ijms22073636 SN - 1422-0067 VL - 22 IS - 7 PB - MDPI AG ER - TY - JOUR A1 - Bartosova, Maria A1 - Schaefer, Betti A1 - Zhang, Conghui A1 - Herzog, Rebecca A1 - Ridinger, David A1 - Damgov, Ivan A1 - Levai, Eszter A1 - Marinovic, Iva A1 - Eckert, Christoph A1 - Romero, Philipp A1 - Sallay, Peter A1 - Ujszaszi, Akos A1 - Unterwurzacher, Markus A1 - Wagner, Anja A1 - Hildenbrand, Georg A1 - Warady, Bradley A1 - Schaefer, Franz A1 - Zarogiannis, Sotirios G. A1 - Kratochwill, Klaus A1 - Schmitt, Claus Peter T1 - Glucose Derivative Induced Vasculopathy in Children on Chronic Peritoneal Dialysis JF - Nephrology Dialysis Transplantation N2 - Abstract Background and Aims Patients with chronic kidney disease patients (CKD) have an exceedingly high cardiovascular risk. While vasculopathy is further accelerated during peritoneal dialysis (PD), the pathophysiological role of reactive metabolites such as glucose degradation products (GDP) is uncertain. Method Omental and parietal peritoneal tissues from 100 non-CKD individuals, 107 children with CKD5, 60 children treated with neutral pH, low GDP, and 30 children treated with acidic pH, high GDP PD fluids underwent standardized digital histomorphometry. Omental arterioles localized within the fat tissue, protected from direct PD fluid exposure were microdissected for multi-omics analysis. Key regulated pathways were validated by quantitative immunostaining, with localization microscopy in peritoneal tissues of matched cohorts and in vitro in human umbilical vein endothelial cells. Results Arterioles from children with CKD5 exhibited reduced lumen to vessel ratio (L/V) and reduced endothelial telomere length compared to non-CKD individuals; gene ontology analysis identified enrichment of arteriolar genes associated with nuclear telomere cap complex and focal adhesion. Pathway analysis of arteriolar cross-omics identified top canonical pathways including telomere extension by telomerase, actin cytoskeleton, integrin and tight junction signalling. Peritoneal vasculopathy progressed with PD vintage and was more pronounced with high versus low GDP exposure (p&lt;0.001). Compared to CKD5, low GDP-PD upregulated 145/110 and downregulated 38/34 arteriolar genes/proteins, high GDP-PD upregulated 684/137 and supressed 1560/55 genes/proteins (p&lt;0.01). High GDP milieu induced upregulation of arteriolar genes involved in cell death/apoptosis and suppressed genes related to cell viability/survival, cytoskeleton organization and immune response biofunctions. Vasculopathy associated canonical pathways concordantly regulated on arteriolar gene and protein level with high GDP exposure included cell death/proliferation, apoptosis, cytoskeleton organization, metabolism and detoxification, cell junction signalling, and immune response. Quantitative validation in PD cohorts with similar PD vintage, dialytic glucose exposure and age (n=15 / group) verified increased proapoptotic activity and cytoskeleton disintegration with high-GDP exposure; single-molecule-localization microscopy demonstrated arteriolar endothelial zonula occludens-1 (ZO-1) disruption. Absolute and relative to endoluminal surface length, arteriolar endothelial cell counts were inversely correlated with GDP exposure, with apoptosis marker caspase-3, TGF-ß induced pSMAD2/3, interleukin-6, ZO-1 protein abundance and the degree of vasculopathy. In vitro, exposure to GDP 3,4-dideoxyglucosone-3-ene dose-dependently reduced nuclear endothelial lamin-A/C and membrane ZO-1 assembly. Transendothelial electrical resistance was decreased. ZO-1 and sealing tight junction claudin-5 protein abundance were decreased in cells after incubation with high GDP compared to low GDP PD fluid and culture media. On nanoscale level GDP reduced junction cluster formation in the membrane area. Conclusion Multi-omics analysis of omental arterioles from children without pre-existing vasculopathy and life-style related confounders identified key mechanisms of vascular aging in CKD5 and the major contribution of GDP to accelerated vasculopathy during PD, i.e. disruption of endothelial cell junctions and cytoskeleton and induction of apoptosis. KW - Peritonealdialyse KW - Gefäßkrankheit KW - Kind Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1093/ndt/gfab126.004 SN - 0931-0509 VL - 36 IS - Supplement_1 PB - Oxford University Press (OUP) ER - TY - JOUR A1 - Bartosova, Maria A1 - Zhang, Conghui A1 - Schaefer, Betti A1 - Herzog, Rebecca A1 - Ridinger, David A1 - Damgov, Ivan A1 - Levai, Eszter A1 - Marinovic, Iva A1 - Eckert, Christoph A1 - Romero, Philipp A1 - Sallay, Peter A1 - Ujszaszi, Akos A1 - Unterwurzacher, Markus A1 - Wagner, Anja A1 - Hildenbrand, Georg A1 - Warady, Bradley A. A1 - Schaefer, Franz A1 - Zarogiannis, Sotirios G. A1 - Kratochwill, Klaus A1 - Schmitt, Claus Peter T1 - Glucose Derivative Induced Vasculopathy in Children on Chronic Peritoneal Dialysis JF - Circulation Research N2 - Rationale: Patients with chronic kidney disease (CKD) have an exceedingly high cardiovascular risk; which further increases in patients on peritoneal dialysis (PD). The pathophysiological role of reactive metabolites accumulating in CKD such as glucose degradation products (GDP) is uncertain. Objective: Delineating the impact of GDP present in PD fluids in accelerated vasculopathy development in patients with CKD. Methods and Results: Omental and parietal peritoneal tissues were obtained from 107 children with CKD before dialysis and 90 children on chronic PD with PD fluids containing very low or high concentrations of GDP. Omental arterioles, protected from local PD fluid exposure by surrounding fat, were microdissected for multiomics analyses. High-GDP exposed omental arterioles exhibited 3-fold higher advanced glycation endproduct concentrations and upregulated genes involved in cell death/apoptosis and suppressed genes related to cell viability/survival, cytoskeleton organization, and immune response biofunctions. Vasculopathy-associated canonical pathways concordantly regulated on gene and protein level with high-GDP exposure included cell death/proliferation, apoptosis, cytoskeleton organization, metabolism and detoxification, cell junction signaling, and immune response. Parietal peritoneal arterioles of patients exposed to high-GDP fluids exhibited lumen narrowing compared to patients with CKD stage 5 (end-stage kidney disease) and patients on low-GDP PD, intima thickness was increased. Protein quantification verified increased proapoptotic activity and cytoskeleton disintegration, single-molecule-localization microscopy demonstrated arteriolar endothelial ZO-1 (zonula occludens-1) disruption. Absolute and per endoluminal surface length, arteriolar endothelial cell counts inversely correlated with GDP exposure, caspase-3, TGF (transforming growth factor)-β–induced pSMAD2/3 (phosphorylated SMAD2/3), interleukin-6, ZO-1 abundance, and lumen narrowing. In vitro, 3,4-dideoxyglucosone-3-ene reduced lamin-A/C and membrane ZO-1 assembly, increased pSMAD2/3, and ionic and 4 and 10 kDa permeability of arterial endothelial cells. Conclusions: Our findings indicate a fundamental role of GDP in PD-associated vasculopathy, exerted by endothelial cell junction and cytoskeleton disruption, and induction of apoptosis. They should redirect the focus of research and intervention on targeting reactive metabolite overload in CKD and PD. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01893710. KW - Peritonealdialyse KW - Gefäßkrankheit KW - Kind Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1161/CIRCRESAHA.121.319310 SN - 0009-7330 VL - 129 IS - 5 PB - Ovid Technologies (Wolters Kluwer Health) ER - TY - INPR A1 - Paschek, Klaus A1 - Roßmann, Arthur A1 - Hausmann, Michael A1 - Hildenbrand, Georg T1 - Analysis of Tidal Accelerations in the Solar System and in Extrasolar Planetary Systems N2 - Volcanism powered by tidal forces inside celestial bodies can provide enough energy to keep important solvents for living systems in the liquid phase. Moreover, tidal forces and their environmental consequences may strongly influence habitability of planets and other celestial bodies and may result in special forms of live and living conditions. A prerequisite to calculate such tidal interactions and consequences is depending on simulations for tidal accelerations in a multi-body system. Unfortunately, from measurements in many extrasolar planetary systems only few physical and orbital parameters are well enough known for investigated celestial bodies. For calculating tidal acceleration vectors under missing most orbital parameter exactly, a simulation method is developed that is only based on a few basic parameters, easily measurable even in extrasolar planetary systems. Such a method as being presented here, allows finding a relation between the tidal acceleration vectors and potential heating inside celestial objects. Using values and results of our model approach to our solar system as a “gold standard” for feasibility allowed us to classify this heating in relation to different forms of volcanism. This “gold standard” approach gave us a classification measure for the relevance of tidal heating in other extrasolar systems with a reduced availability of exact physical parameters. We would help to estimate conditions for the identification of potential candidates for further sophisticated investigations by more complex established methods like viscoelastic multi-body theories. As a first example, we applied the procedures developed here to the extrasolar planetary system TRAPPIST-1 as an example to check our working hypothesis. KW - Sonnensystem KW - Vulkanismus Y1 - 2021 U6 - https://doi.org/https://doi.org/10.20944/preprints202107.0408.v1 PB - MDPI AG ER - TY - JOUR A1 - Bartosova, Maria A1 - Ridinger, David A1 - Marinovic, Iva A1 - Heigwer, Jana A1 - Zhang, Conghui A1 - Levai, Eszter A1 - Westhoff, Jens H. A1 - Schaefer, Franz A1 - Terjung, Stefan A1 - Hildenbrand, Georg A1 - Krunic, Damir A1 - Bestvater, Felix A1 - Hausmann, Michael A1 - Schmitt, Claus Peter A1 - Zarogiannis, Sotirios G. T1 - An Experimental Workflow for Studying Barrier Integrity, Permeability, and Tight Junction Composition and Localization in a Single Endothelial Cell Monolayer: Proof of Concept JF - International Journal of Molecular Sciences N2 - Endothelial and epithelial barrier function is crucial for the maintenance of physiological processes. The barrier paracellular permeability depends on the composition and spatial distribution of the cell-to-cell tight junctions (TJ). Here, we provide an experimental workflow that yields several layers of physiological data in the setting of a single endothelial cell monolayer. Human umbilical vein endothelial cells were grown on Transwell filters. Transendothelial electrical resistance (TER) and 10 kDa FITC dextran flux were measured using Alanyl-Glutamine (AlaGln) as a paracellular barrier modulator. Single monolayers were immunolabelled for Zonula Occludens-1 (ZO-1) and Claudin-5 (CLDN5) and used for automated immunofluorescence imaging. Finally, the same monolayers were used for single molecule localization microscopy (SMLM) of ZO-1 and CLDN5 at the nanoscale for spatial clustering analysis. The TER increased and the paracellular dextran flux decreased after the application of AlaGln and these functional changes of the monolayer were mediated by an increase in the ZO-1 and CLDN5 abundance in the cell–cell interface. At the nanoscale level, the functional and protein abundance data were accompanied by non-random increased clustering of CLDN5. Our experimental workflow provides multiple data from a single monolayer and has wide applicability in the setting of paracellular studies in endothelia and epithelia. KW - Endothelzelle KW - Nabelvene Y1 - 2021 U6 - https://doi.org/https://doi.org/10.3390/ijms22158178 SN - 1422-0067 VL - 22 IS - 15 PB - MDPI AG ER - TY - JOUR A1 - Paschek, Klaus A1 - Roßmann, Arthur A1 - Hausmann, Michael A1 - Hildenbrand, Georg T1 - Analysis of Tidal Accelerations in the Solar System and in Extrasolar Planetary Systems JF - Applied Sciences N2 - Volcanism powered by tidal forces inside celestial bodies can provide enough energy to keep important solvents for living systems in the liquid phase. A prerequisite to calculate such tidal interactions and consequences is depending on simulations for tidal accelerations in a multi-body system. Unfortunately, from measurements in many extrasolar planetary systems, only few physical and orbital parameters are well-known enough for investigated celestial bodies. For calculating tidal acceleration vectors under missing most orbital parameter exactly, a simulation method is developed that is only based on a few basic parameters, easily measurable even in extrasolar planetary systems. Such a method as the one presented here allows finding a relation between the tidal acceleration vectors and potential heating inside celestial objects. Using the values and results of our model approach to our solar system as a “gold standard” for feasibility allowed us to classify this heating in relation to different forms of volcanism. This “gold standard” approach gave us a classification measure for the relevance of tidal heating in other extrasolar systems with a reduced availability of exact physical parameters. We help to estimate conditions for the identification of potential candidates for further sophisticated investigations by more complex established methods such as viscoelastic multi-body theories. As a first example, we applied the procedures developed here to the extrasolar planetary system TRAPPIST-1 as an example to check our working hypothesis. KW - Sonnensystem KW - Vulkanismus Y1 - 2021 U6 - https://doi.org/https://doi.org/10.3390/app11188624 SN - 2076-3417 VL - 11 IS - 18 PB - MDPI AG ER - TY - JOUR A1 - Sievers, Aaron A1 - Sauer, Liane A1 - Hausmann, Michael A1 - Hildenbrand, Georg T1 - Eukaryotic Genomes Show Strong Evolutionary Conservation of k-mer Composition and Correlation Contributions between Introns and Intergenic Regions JF - Genes N2 - Several strongly conserved DNA sequence patterns in and between introns and intergenic regions (IIRs) consisting of short tandem repeats (STRs) with repeat lengths <3 bp have already been described in the kingdom of Animalia. In this work, we expanded the search and analysis of conserved DNA sequence patterns to a wider range of eukaryotic genomes. Our aims were to confirm the conservation of these patterns, to support the hypothesis on their functional constraints and/or the identification of unknown patterns. We pairwise compared genomic DNA sequences of genes, exons, CDS, introns and intergenic regions of 34 Embryophyta (land plants), 30 Protista and 29 Fungi using established k-mer-based (alignment-free) comparison methods. Additionally, the results were compared with values derived for Animalia in former studies. We confirmed strong correlations between the sequence structures of IIRs spanning over the entire domain of Eukaryotes. We found that the high correlations within introns, intergenic regions and between the two are a result of conserved abundancies of STRs with repeat units ≤2 bp (e.g., (AT)n). For some sequence patterns and their inverse complementary sequences, we found a violation of equal distribution on complementary DNA strands in a subset of genomes. Looking at mismatches within the identified STR patterns, we found specific preferences for certain nucleotides stable over all four phylogenetic kingdoms. We conclude that all of these conserved patterns between IIRs indicate a shared function of these sequence structures related to STRs. KW - Genom KW - Eukaryoten Y1 - 2021 U6 - https://doi.org/https://doi.org/10.3390/genes12101571 SN - 2073-4425 VL - 12 IS - 10 PB - MDPI AG ER - TY - CHAP A1 - Büdel, Johannes A1 - Herkommer, Christian A1 - Kuhlmann, Kai A1 - Teigelkötter, Johannes T1 - Advanced DC-charging Methods for Traction Drives with Dual Two-Level Inverter During Machine Operation T2 - 2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe) N2 - This paper aims to present a concept and especially developed control methods for an open-end winding traction drive, powered by a dual two-level inverter, where the two separate energy sources can be charged via a DC grid during operation and while being standstill. For achieving a high quality DC-current, the parasitic Back-EMF harmonics of the electrical machine will be compensated. The application aims to achieve high utilisation of the electric vehicle in combination with a partly equipped trolley wire net. KW - Wechselrichter KW - Elektroantrieb KW - Elektrofahrzeug Y1 - 2021 U6 - https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570611 ER - TY - JOUR A1 - Lieb, Florian A1 - Knopp, Tobias T1 - A wavelet-based sparse row-action method for image reconstruction in magnetic particle imaging JF - Medical Physics N2 - Purpose Magnetic particle imaging (MPI) is a preclinical imaging technique capable of visualizing the spatio-temporal distribution of magnetic nanoparticles. The image reconstruction of this fast and dynamic process relies on efficiently solving an ill-posed inverse problem. Current approaches to reconstruct the tracer concentration from its measurements are either adapted to image characteristics of MPI but suffer from higher computational complexity and slower convergence or are fast but lack in the image quality of the reconstructed images. Methods In this work we propose a novel MPI reconstruction method to combine the advantages of both approaches into a single algorithm. The underlying sparsity prior is based on an undecimated wavelet transform and is integrated into a fast row-action framework to solve the corresponding MPI minimization problem. Results Its performance is numerically evaluated against a classical FISTA (Fast Iterative Shrinkage-Thresholding Algorithm) approach on simulated and real MPI data. The experimental results show that the proposed method increases image quality with significantly reduced computation times. Conclusions In comparison to state-of-the-art MPI reconstruction methods, our approach shows better reconstruction results and at the same time accelerates the convergence rate of the underlying row-action algorithm. KW - Wavelet KW - Bildgebendes Verfahren KW - Magnetpartikelbildgebung Y1 - 2021 UR - https://doi.org/10.1002/mp.14938 VL - 48 IS - 7 SP - 3893 EP - 3903 ER - TY - CHAP A1 - Schork, Sabrina T1 - Circular Innovator Education T2 - Ability to Act N2 - The following article is a first step towards raising the awareness of these new trainers (who are conscious and innovators themselves) and giving them methods, tools, and inspiration to develop sustainable innovators to think holistically. Innovators are the proportion of entrepreneurs who do not copy or optimize what already exists but commercialize new technologies or new ideas. Circular innovators are the doers who create systemic innovations solving our current social and ecological crisis. KW - Innovationsmanagement Y1 - 2021 VL - 2021 SP - 105 EP - 124 PB - BoekenGilde CY - Enschede, Netherlands ER - TY - CHAP A1 - Schork, Sabrina T1 - Innovation Leadership in the Digital Enterprise: Lessons From Pioneers T2 - Handbook of Research on Management and Strategies for Digital Enterprise Transformation N2 - In this chapter, the EIL (Effective Innovation Leadership) framework is tested empirically. First, peer-reviewed journals in the innovation management, leadership, and transformation discipline are analyzed. Second, a pre-test with 58 executives takes place. The response behavior of the participants varies depending on the company's degree of digital maturity. Third, 20 innovation leaders employed in mature digital companies answer the survey. The participants perceive their company as innovative and state that up to 89% of created innovations are digital. Values relevant to digital innovation leaders are innovation, responsibility, positivity, and transparency. Relevant strengths are creativity and learning. Both strongly correlate with a few efficacy items. Decisiveness correlates with innovation strategy. Entrepreneurship, self-regulation, and culture correlate with each other. Creativity connects the value of innovation and the practice of communication. The insights from this chapter contribute to building a reliable and valid factor-based effective digital innovation leadership questionnaire in the future. KW - Innovationsmanagement KW - Digitalisierung KW - Führung Y1 - 2021 UR - https://www.igi-global.com/chapter/innovation-leadership-in-the-digital-enterprise/273781 SP - 86 EP - 109 PB - IGI Global CY - Hershey, Pennsylvania, USA ER - TY - CHAP A1 - Kefer, Stefan A1 - Schmauss, Bernhard A1 - Hellmann, Ralf T1 - POLYMER PLANAR BRAGG GRATINGS BASED ON BULK CYCLIC OLEFIN COPOLYMERS: FABRICATION AND FUNCTIONALIZATION T2 - Proceedings of Student Conference on Sensors, Systems and Measurement 2021 KW - Bragg-Reflektor Y1 - 2021 UR - https://scssm.fel.cvut.cz/wp-content/uploads/2021/07/Proceedings-SCSSM-2021.pdf SN - 978-80-01-06822-9 ER - TY - THES A1 - Ciba, Manuel T1 - Synchrony Measurement and Connectivity Estimation of Parallel Spike Trains from in vitro Neuronal Networks KW - Neuronales Netz Y1 - 2021 U6 - https://doi.org/https://doi.org/10.25972/OPUS-22364 ER - TY - JOUR A1 - Sommer, David A1 - Götzendorfer, Babette A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Design Rules for Hybrid Additive Manufacturing Combining Selective Laser Melting and Micromilling JF - Design and Post Processing for Metal Additive Manufacturing N2 - We report on a comprehensive study to evaluate fundamental properties of a hybrid manufacturing approach, combining selective laser melting and high speed milling, and to characterize typical geometrical features and conclude on a catalogue of design rules. As for any additive manufacturing approach, the understanding of the machine properties and the process behaviour as well as such a selection guide is of upmost importance to foster the implementation of new machining concepts and support design engineers. Geometrical accuracy between digitally designed and physically realized parts made of maraging steel and dimensional limits are analyzed by stripe line projection. In particular, we identify design rules for numerous basic geometric elements like walls, cylinders, angles, inclinations, overhangs, notches, inner and outer radii of spheres, chamfers in build direction, and holes of different shape, respectively, as being manufactured by the hybrid approach and compare them to sole selective laser melting. While the cutting tool defines the manufacturability of, e.g., edges and corners, the milling itself improves the surface roughness to Ra < 2 µm. Thus, the given advantages of this hybrid process, e.g., space-resolved and custom-designed roughness and the superior geometrical accuracy are evaluated. Finally, we exemplify the potential of this particular promising hybrid approach by demonstrating an injection mold with a conformal cooling for a charge socket for an electro mobile KW - hybrid additive manufacturing; high-speed milling; selective laser melting; construction rules KW - Selektives Laserschmelzen KW - Hochgeschwindigkeitsfräsen Y1 - 2021 UR - https://www.mdpi.com/1996-1944/14/19/5753 U6 - https://doi.org/https://doi.org/10.3390/ma14195753 VL - 14 IS - 19 SP - 1 EP - 23 ER - TY - BOOK A1 - Borgeest, Kai T1 - Manipulation von Abgaswerten N2 - Dieses Buch stellt Hintergründe zum Abgasskandal dar, z. B. welche Schadstoffe kritisch sind, wie Motorsteuergeräte, Abgasrückführung und Abgasnachbehandlung funktionieren, wie Manipulationen auf dem Prüfstand möglich sind, mit welchen Fahrzyklen getestet wird und in welchem rechtlichen und politischen Umfeld dies lange Zeit geschehen konnte. Es werden Maßnahmen vorgestellt, mit denen Fahrzeuge auch real Grenzwerte einhalten können und wie Manipulationen zukünftig rechtlich und politisch verhindert werden können. Dem Leser werden durch Literaturhinweise zusätzliche Details erschlossen. KW - Verbrennungsmotor KW - Kraftfahrzeugabgas KW - Motorsteuerung KW - Abgasskandal KW - Abschalteinrichtung KW - EDC Y1 - 2021 SN - 978-3-658-32810-8 VL - 2021 PB - Springer Vieweg CY - Wiesbaden ET - 2., überarbeitete und aktualisierte Auflage ER - TY - CHAP A1 - Büdel, Johannes A1 - Kuhlmann, Kai A1 - Herkommer, Christian A1 - Teigelkötter, Johannes T1 - Advanced Control Methods for High Performance Dual Two-Level Inverter for Traction Application T2 - Electromechanical Drive Systems 2021; ETG Symposium; 9-10 Nov. 2021 N2 - The topology of the dual two-level inverter in combination with an electrical machine with open-end winding is an optimal solution for the realization of high requirements from the automotive sector for high-performance traction drives. In this publication, methods for extending the operating range and improving output voltage and current quality are presented for synchronous as well as asynchronous PWM methods for the entire operating range for this system configuration. Emphasis is placed on symmetrical power sharing between the inverters to maximize the power range. Optimal integration of the system is achieved by the topology-related possibility of DC fast charging of the energy storages from a DC grid without an additional charging unit. KW - Wechselrichter KW - Elektrische Maschine KW - Elektroantrieb KW - Traktion, Kraftfahrzeugtechnik Y1 - 2021 SN - 978-3-8007-5685-8 ER - TY - CHAP A1 - Sauer, Timm A1 - Zindler, Klaus A1 - Gorks, Manuel A1 - Spielmann, Luca A1 - Jumar, Ulrich T1 - Automatic track guidance of industrial trucks using self-learning controllers considering a priori plant knowledge T2 - IEEE - 5th International Conference on Control Automation and Diagnosis (ICCAD'21), November 3-5, 2021, Grenoble, France N2 - This paper presents a new self-learning control scheme for lateral track guidance of industrial trucks using artificial intelligence. It is an universally applicable lateral dynamic control concept which is able to adapt itself to different truck variants. Moreover it shall consider vehicle parameter variations that occur during operation, such as the load dependent change of vehicle mass and moment of inertia. The proposed approach uses Reinforcement Learning. In order to reduce the training effort, a new concept is realized, taking into account a priori knowledge of vehicle behavior. Its fundamental idea consists of dividing the training process into two steps. In the first step the controller will be pre-trained on basis of a nominal model representing a priori knowledge of lateral dynamic vehicle behavior. Since this model is derived for an industrial truck with average vehicle parameter values, a fine tuning of the control parameters has to be performed in the second step. In this way the controller is adapted to the actual truck variant and the corresponding vehicle parameter values. In order to demonstrate the efficiency of the proposed control scheme, the simulation results given in this paper are compared to the closed loop behavior using standard LQR. KW - Labor für Simulation, Steuerung und Regelung KW - Kooperative Autonome Intralogistik Systeme KW - Flurförderer KW - Spurführung KW - Künstliche Intelligenz Y1 - 2021 ER - TY - JOUR A1 - Rung, Stefan A1 - Häcker, Niklas A1 - Hellmann, Ralf T1 - Thermal imaging of high power ultrashort pulse laser ablation of alumina towards temperature optimized micro machining strategies JF - IOP Conference Series: Materials Science and Engineering KW - Ultrakurzzeitlaser KW - Aluminiumoxide Y1 - 2021 UR - https://iopscience.iop.org/article/10.1088/1757-899X/1135/1/012027 U6 - https://doi.org/0.1088/1757-899X/1135/1/012027 VL - 1135 IS - 012027 SP - 1 EP - 9 ER - TY - JOUR A1 - Rung, Stefan A1 - Hellmann, Ralf T1 - Laser-Induced Period Surface Structures to Improve Solderability of Electrical Solder Pads JF - Applied Sciences KW - Laserstrahllöten Y1 - 2021 UR - https://www.mdpi.com/2076-3417/12/1/80/htm U6 - https://doi.org/10.3390/app12010080 VL - 2022 IS - 12/1 SP - 80 EP - 88 ER - TY - RPRT A1 - Smeets, Mario A1 - Ostendorf, Ralf A1 - Rötzel, Peter T1 - RPA for the financial industry N2 - Abstract: Like many service industries, the financial industry is largely characterized by administrative and back-office processes and distinguished by a broad systems landscape with a high proportion of legacy systems. Missing interfaces between information systems, user interfaces, or web applications often require many manual activities. As banks are often functionally organized into traditional departments, a process-oriented organizational structure is rarely in place. The financial industry therefore offers enormous potential for the use of robotic process automation (RPA) and the raising of potential benefits such as process-related cost savings, time reductions, and quality improvements. The aim of this chapter is to describe the tremendous opportunities that the use of RPA technology offers to the financial industry and to explain how these opportunities can be realized. Therefore, we start by explaining the challenges that progressive digitalization poses to the industry and how RPA, but also more advanced technologies (that work not only rule-based but also define own rules), such as artificial intelligence, can help to overcome them. As well as providing an overview of the various applications of RPA in the financial industry, we also provide a comprehensive case study of a relevant practical application KW - Robotic Process Automation KW - Finanzdienstleistung Y1 - 2021 ER - TY - RPRT A1 - Jost, Thomas A1 - Tödter, Karl-Heinz T1 - Reducing sovereign debt levels in the post-Covid Eurozone with a simple deficit rule T2 - IMFS Working Paper Series KW - Eurozone KW - Öffentliche Schulden KW - Eurozone KW - Fiscal Rules KW - Maastricht Criteria KW - Stability and Growth Pact Y1 - 2021 UR - https://www.imfs-frankfurt.de/forschung/imfs-working-papers/details/publication/reducing-sovereign-debt-levels-in-the-post-covid-eurozone-with-a-simple-deficit-rule.html ER - TY - CHAP A1 - Probst, Anne-Catherine A1 - Hitzinger, Hans A1 - Bochtler, Ulrich A1 - Wölfel, Maximilian A1 - Schmitt, Christoph ED - U.R.S.I. Landesausschuss in Deutschland e.V. 2021, T1 - High Frequency Power Amplifier for Wideband Wireless Communication Systems T2 - Proceedings of the 2021 Kleinheubach Conference N2 - Increasing data transmission rates and bandwidth both belong to the challenges of the development of high-performance wireless communication systems. Multi-channel communication systems commonly use several narrowband power amplifiers each one for a single communication channel. Lossy couplers are needed both to separate the different channels from each other at the amplifiers input and to combine the amplified signals on each channel at the output. This approach depicts a poor efficiency and is limited to a few number of channels since each channel duplication involves 3 dB losses due to couplers. Alternatively, broadband radio frequency power amplifiers ensuring the simultaneous transmission of several carriers on a wide frequency range contribute to increase the cost and resource efficiency of transceivers in wireless communication systems. Gain flatness, a high output power, and low power levels of second and third order harmonics are required on the whole operating frequency range of the power amplifier in multi-carrier communication systems since overtones will degrade the quality of the communication. The present work investigates the performances of a broadband push-pull power amplifier based on LDMOS transistors, the input matching network using a 8:1 transmission line transformer. For the first time investigations on harmonic distortions of the amplified signal when using a transformer with 8:1 impedance transformation ratio are presented. Characterisation of the power amplifiers performances is focused on gain flatness, output power, harmonic distortions and efficiency at 110 W. KW - LDMOS KW - broadband RF power amplifier KW - push-pull KW - transmission line transformer KW - harmonic distortion KW - Hochfrequenzverstärker KW - Leistungsverstärker KW - Kommunikationssystem Y1 - 2021 U6 - https://doi.org/10.23919/IEEECONF54431.2021.9598443 VL - 2021 ER - TY - CHAP A1 - Döhring, Thorsten A1 - Rödling, Claudius A1 - Kimmel, Kevin A1 - Zeising, Sebastian A1 - Stadtmüller, Johannes A1 - Stollenwerk, Manfred A1 - Verma, Shruti A1 - Rees, Paul T1 - Optical characterization of reflective coatings for astronomical telescope mirrors T2 - DGaO Proceedings N2 - Aluminium evaporation is still the standard solution for reflective coatings of large astronomical mirrors. Silver and gold are also used in specific cases depending on the targeted wavelength. This study characterized different metallic coatings - including unusual ones like sputtered iridium - to identify the most suitable mirror coating for the spectral range from ultraviolet to infrared wavelengths. KW - Iridium KW - mirror KW - coating KW - reflectivity KW - telescope KW - Spiegelteleskop Y1 - 2021 UR - https://www.dgao-proceedings.de/download/122/122_p4.pdf SN - 1614-8436 VL - 2021 IS - 122 SP - 1 EP - 1 PB - DGaO ER - TY - CHAP A1 - Döhring, Thorsten A1 - Stadtmüller, Johannes A1 - Stollenwerk, Manfred A1 - Cotroneo, Vincenzo A1 - Pareschi, Giovanni A1 - Gibertini, Eugenio A1 - Magagnin, Luca T1 - Low-density coatings for enhanced X-ray reflectivity of astronomical telescope mirrors T2 - DGaO Proceedings N2 - High reflectivity grazing incidence mirrors of astronomical X-ray telescopes are usually coated with thin layers of iridium, gold, or platinum. Due to a series of absorption edges, these noble metals have low reflectivity in the 2 - 4 keV band. We present the development of innovative material combinations using chromium and an additional layer of polydopamine for enhanced reflectivity X-ray coatings. KW - Dopamin KW - Iridium KW - mirror KW - coating KW - X-ray KW - Röntgenteleskop Y1 - 2021 UR - https://www.dgao-proceedings.de/download/122/122_p3.pdf SN - 1614-8436 VL - 2021 IS - 122 SP - 1 EP - 2 PB - DGaO ER - TY - CHAP A1 - Döhring, Thorsten A1 - Stieglitz, Veronika A1 - Burwitz, Vadim A1 - Hartner, Gisela A1 - Müller, Thomas A1 - Schmidt, Thomas A1 - Rukdee, Surangkhana A1 - Friedrich, Peter A1 - Sahin, Fatih A1 - Hudec, Rene T1 - Charakterisierung von Weitwinkel-Röntgenteleskopen in der Testanlage PANTER T2 - DGaO Proceedings N2 - Im Rahmen einer bayerisch-tschechischen Kooperation entstanden zwei Röntgenteleskope, bestückt mit Gold- und Iridium-beschichteten Planspiegeln. Deren Charakterisierung erfolgte an der Röntgentestanlage PANTER, welche parallel auf die Teleskope einfallendes Sternenlicht simuliert. Die Teleskope haben eine Winkelauflösung von ca. 4 Bogenminuten und eine Brennweite von rund 2 Metern. KW - Röntgenstrahlung KW - Teleskop KW - Iridium KW - Beschichtung KW - Astronomie KW - Röntgenteleskop KW - Iridium KW - Spiegelteleskop Y1 - 2021 UR - https://www.dgao-proceedings.de/download/122/122_p2.pdf SN - 1614-8436 VL - 2021 IS - 122 SP - 1 EP - 2 PB - DGaO ER - TY - JOUR A1 - Butz-Seidl, Annemarie T1 - Zuwendungsnießbrauch an GmbH-Anteilen: Gestaltungschancen und Risiken JF - Erbfolgebesteuerung N2 - Der unentgeltliche Zuwendungsnießbrauch an GmbH-Beteiligungen ist eine häufig genutzte Gestaltung, die auf die Versorgung von Angehörigen im Rahmen der vorweggenommenen Erbfolge abzielt. Aus wirtschaftlicher Sicht soll mit der Bestellung Nicht-Gesellschaftern eine regelmäßige Einkunftsquelle verschafft werden; daneben gilt es, bei den Beteiligten ertragsteuerliche, erbschaft- und schenkungsteuerliche Privilegien zu nutzen. Konkret geht es und die Ausschöpfung von Progressionsvorteilen und Freibeträgen. Grundsätzlich bleibt aber festzuhalten, dass die Bestellung eines Zuwendungsnießbrauchs an GmbH-Anteilen nach wie vor mit erheblichen rechtlichen und steuerlichen Unsicherheiten behaftet ist. KW - GmbH-Anteile; Zuwendungsnießbrauch; vorweggenommene Erbfolge; Zivilrecht; Ertragsteuerrecht; Schenkungsteuerrecht; KW - Nießbrauch KW - GmbH KW - Vorweggenommene Erbfolge KW - Steuerrecht Y1 - 2021 VL - 2021 IS - 12 SP - 313 EP - 318 ER - TY - GEN A1 - Jost, Thomas ED - Main-Echo, T1 - Die Gefahr ultraexpansiver Geldpolitik KW - Geldpolitik KW - Europäische Zentralbank Y1 - 2021 ER - TY - CHAP A1 - Freudenmann, Dominic A1 - Stollenwerk, Manfred A1 - Döhring, Thorsten A1 - Stadtmüller, Johannes A1 - Negri, Michele A1 - Lauck, Felix T1 - Combustion efficiency of iridium coated pellets for environmentally friendly space propulsion T2 - 14th Pico- and Nanosatellite Workshop, Würzburg, Germany N2 - Most of the satellite engines still uses critical fuels such as hydrazine, which is chemically aggressive, toxic and carcinogenic. New developments for satellite engines try to avoid such critical propellants. One promising approach is the usage of rocket-grade hydrogen peroxide [H2O2] in mono- and bipropellant driven rocket engines. Catalysts in the rocket engines convert the hydrogen peroxide by an exothermic catalytic reaction; the resulting hot gases oxygen and water vapor provide the thrust. Currently used catalysts are, for example, Al2O3 pellets impregnated with platinum. Within a joint research project of Aschaffenburg University and the German Aerospace Center new catalysts are developed. They consist of ceramic pellets coated with iridium using the magnetron sputtering process. Thereby the surface structure of the iridium layers strongly depends on the used sputtering process conditions [1]. After optimization of the sputtering parameters, it was demonstrated in laboratory experiments that the catalytic effect (measured by the volume of released gas) can be increased by a factor of four compared to platinum impregnated pellets [2]. In first hot firing tests at the test bench complex M11 at the DLR- Institute of Space Propulsion, these new, iridium-based catalysts have been used in a model combustion chamber for hydrogen peroxide decomposition. For this purpose, the reaction chamber was filled with iridium pellets in the high-altitude simulation chamber of the M11.2 test bench. The model chamber was equipped with numerous measuring devices like temperature and pressure sensors (e.g. Tcat, pcat). With the help of the mass flow and the herein obtained data, performance characteristics of the propellant system were accessible. High-concentrated hydrogen peroxide was used in the experiments as monopropellant (~ 87-wt.% H2O2). During the experiments, the combustion chamber was operated in pulse mode and in continuous mode. Aim of this campaign called MoCa (“Monopropellant Catalytic Demonstrator”) is the demonstration of functionality and the performance evaluation of this iridium-based monopropellant system. Recent experimental results will be presented. References: [1] A. Büttner et al., Thin Solid Films 2018, 662: 41–46 [2] M. Stollenwerk et al., Journal of Materials Science 2021, 56(16), 9974-9984 KW - Satellitentechnik KW - Katalysator KW - Iridium Y1 - 2021 ER - TY - GEN A1 - Hudec, Rene A1 - Novakova, Hana A1 - Pritzl, Vaclav A1 - Vojnar, Jan A1 - Döhring, Thorsten T1 - CubeSat mission for the observation of meteoroid impacts on Moon T2 - DGaO Jahrestagung N2 - Recent progress in nanosatellite technologies allows to consider innovative new CubeSat missions for scientific purposes. We present and evaluate the design of a small and cost effective CubeSat mission to monitor lunar meteoroid impacts by detecting their optical flashes. The poster summarizes the results of a comprehensive survey of past and recent ground based and satellite based projects focussing on lunar impact monitoring and discusses important aspects of the proposed mission and various alternatives for their solutions. Several spacecraft orbits around Moon and their usefulness for lunar impact observation are studied. In addition, we discuss the environmental risks and challenges, which such spacecraft needs to face, mainly thermal management and radiation tolerance. Finally, we present and discuss the design an optical camera suitable to detect meteoroid impacts on the lunar surface. N2 - Poster KW - CubeSat KW - satellite KW - Moon KW - meteroid KW - impact KW - Impakt KW - Mond KW - Satellit Y1 - 2021 UR - https://dgao.de/jahrestagung/ VL - 2021 SP - 1 EP - 1 ER - TY - GEN A1 - Döhring, Thorsten A1 - Rödling, Claudius A1 - Kimmel, Kevin A1 - Zeising, Sebastian A1 - Stadtmüller, Johannes A1 - Stollenwerk, Manfred A1 - Verma, Shruti A1 - Rees, Paul T1 - Optical characterization of reflective coatings for astronomical telescope mirrors T2 - DGaO Jahrestagung N2 - With ground based optical telescopes astronomers observe celestial objects over a wide spectral range. As usually three or even more reflections at telescope mirrors are involved, good reflection properties of the mirror coatings are important. The aluminum evaporation technique has been - and is still - the standard solution for the reflective coatings of large astronomical mirrors. Such coatings have excellent reflectivity in the ultraviolet and in the visible, but perform poorly in the infrared. Silver is the metal having highest reflectivity for wavelengths longward of 400 nm, but isn´t the best choice for reflectivity in the ultraviolet and for blue light. To avoid degradation by oxidation, durable silver coatings need to be protected by transmitting overcoating layers. In the presented study, different metallic coatings – including unusual ones like sputtered iridium - are characterized to identify a coating that is most suitable for the spectral range from ultraviolet to infrared. Experimental results are compared to simulations based on the complex refractive indices of these materials. Thereby dependence of incidence angle and polarization is also considered. N2 - Poster KW - mirror KW - coating KW - iridium KW - astronomy KW - telescope KW - Spiegelteleskop Y1 - 2021 UR - https://dgao.de/jahrestagung/ VL - 2021 SP - 1 EP - 1 ER - TY - GEN A1 - Döhring, Thorsten A1 - Stieglitz, Veronika A1 - Burwitz, Vadim A1 - Hartner, Gisela A1 - Müller, Thomas A1 - Schmidt, Thomas A1 - Rukdee, Surangkhana A1 - Friedrich, Peter A1 - Sahin, Fatih A1 - HUdec, Rene T1 - Charakterisierung von Weitwinkel-Röntgenteleskopen in der Testanlage PANTER T2 - DGaO Jahrestagung N2 - Im Rahmen einer bayerisch-tschechischen Kooperation entstanden zwei mechanisch baugleiche Röntgenteleskope, bestückt mit Gold- und Iridium-beschichteten Planspiegeln. Die Charakterisierung der nach dem ägyptischen Gott HORUS benannten Teleskope erfolgte an der Röntgentestanlage PANTER des Max-Plack-Instituts für extraterrestrische Physik. Diese Vakuum-Testanlage simuliert parallel auf die Teleskope einfallendes Sternenlicht, wobei hier die Strahlung aus einer Röntgenquelle in 120 Metern Abstand stammt. Die Messungen selbst fanden in einer daran angebauten 12 Meter langen Testkammer von 3,5 Metern Durchmesser statt. Im März 2021 sahen die HORUS-Teleskope zum erstem Mal Röntgenlicht. Während der Testkampagne von ca. 54 Stunden Dauer wurden 536 Einzelmessungen an den beiden Teleskopen durchgeführt, bei denen Photonenenergien und Einfallswinkel variiert wurden. Von einer empfindlichen CCD-Kamera, einem Prototyp der eROSITA-Satellitenkamera, wurden hierbei insgesamt 11.153.574 Röntgenphotonen individuell detektiert, analysiert und digital verarbeitet. Die beiden Weitwinkel-Röntgenteleskope haben eine Winkelauflösung von circa 4 Bogenminuten und eine Brennweite von rund zwei Metern. N2 - Poster KW - Röntgenstrahlung KW - Spiegel KW - Teleskop KW - Satellit KW - Iridium KW - Röntgenstrahlung KW - Spiegelteleskop Y1 - 2021 UR - https://dgao.de/jahrestagung/ VL - 2021 SP - 1 EP - 1 ER - TY - GEN A1 - Döhring, Thorsten A1 - Stadtmüller, Johannes A1 - Stollenwerk, Manfred A1 - Cotroneo, Vincenzo A1 - Pareschi, Giovanni A1 - Gibertini, Eugenio A1 - Magagnin, Luca T1 - Low-density coatings for enhanced X-ray reflectivity of astronomical telescope mirrors T2 - DGaO Jahrestagung N2 - X-ray telescopes usually operate in space and are quite different from astronomical telescopes for visible light. For normal angles of incidence, optical light is reflected on the mirror surface, whereas X-rays are either transmitted or absorbed. However, also high reflectivity X-rays mirrors are possible, when the incident rays direction is almost parallel to the mirror surface. Such grazing incidence mirrors are usually coated with thin layers of precious metals like iridium, gold or platinum, as this result in high X-ray reflectivity. These noble metals offer a wide range of reflection up to high photon energies, but, due to a series of absorption edges, have low reflectivity in the 2 - 4 keV band and below. This contribution presents the development of innovative material combinations based on thin layers of iridium and chromium, followed by an additional layer of carbon-based materials. We also discuss corresponding production methods (like dip coating) for enhanced reflectivity mirror coatings of future X-ray telescopes. N2 - Poster KW - X-ray KW - mirror KW - coating KW - iridium KW - satellite KW - Röntgenstrahlung KW - Spiegelteleskop Y1 - 2021 UR - https://dgao.de/jahrestagung/ VL - 2021 SP - 1 EP - 1 ER - TY - GEN A1 - Schwarz, Simon A1 - Hellmann, Ralf T1 - Rapid laser fabrication of complex glass optics T2 - International Research Days N2 - Poster KW - Laserbearbeitung Y1 - 2021 ER - TY - JOUR A1 - Zettl, Julian A1 - Klar, Maximilian A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Laser turning with ultrashort laser pulses JF - Journal of Manufacturing Processes N2 - We report on a comprehensive micromachining study of rotationally symmetric parts using femtosecond laser. A laser turning process with tangential impingement of the laser radiation complemented by a trepanning optics is implemented as to accomplish a true laser lathe micromachining approach. With the objective of optimized ablation rate and reduced surface roughness, the influence of pulse energy, feed rate, trepanning diameter and angular beam incidence, respectively, is investigated for processing stellite rods. We find the smallest feasible feature sizes of 8.5 μm in diameter and smoothest surfaces with an arithmetic average of the roughness profile as low as 0.18 μm. The surface roughness, however, appears to be limited by the occurrence of laser induced periodic surface structures provoked by the femtosecond laser radiation. Furthermore, the variation of the fluence in accordance to the incidence on a curved surface is discussed and the heat input into the material is examined through a longitudinal cross section. KW - Ultrashort laser pulses KW - Turning KW - Ablation rate KW - Tangential processing KW - Trepanning optic KW - Ultrakurzer Lichtimpuls KW - Laserbearbeitung KW - Mikrobearbeitung KW - Femtosekundenlaser Y1 - 2021 U6 - https://doi.org/10.1016/j.jmapro.2021.06.025 VL - 2021 IS - 68 SP - 1562 EP - 1568 ER - TY - JOUR A1 - Zettl, Julian A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Tangential Laser Turning of Fused Silica Using Ultra-short Laser Pulses JF - Journal of Laser Micro/Nanoengineering N2 - Laser turning with ultra-short laser pulses provides the possibility of manufacturing rotationally symmetric geometries, even of hard to machine materials as fused silica, down to a micrometer scale. In this laser micro machining approach, the laser beam is oriented perpendicularly to the rotational axis and tangentially to the material, whereas the target geometry is realized by moving the constantly rotating specimen according to the specified geometry under the focused laser spot. Due to the fric-tion-less laser ablation it is possible to realize a turning process in fused silica without the use of a contacting tool and therefore without causing mechanical tensions in the work piece. The processing head focuses the laser to a calculated spot size of 18 μm in diameter and the applied processing gas pressure assists in removing the ablated material. In this study, femto-second laser turning of fused silica with a diameter of 3.7 mm is investigated. The influence of the applied pulse energy is stated and the use of a trepanning optic during the turning process is characterized. Furthermore, compre-hensive parameter studies in order to optimize roughness and to find the maximum achievable abla-tion rate are shown. Limited by the mechanical speed of the rotational axis, the highest feasible abla-tion rate is 19.5 mm³/min. A roughness of Ra 0.65 μm are demonstrated. KW - Ultra-short Laser Pulses KW - Laser Turning KW - Fused Silica KW - Ablation Rate KW - Process Efficiency KW - Laserbearbeitung KW - Mikrobearbeitung KW - Quarzglas KW - Ultrakurzer Lichtimpuls Y1 - 2021 U6 - https://doi.org/10.2961/jlmn.2021.01.2008 VL - 16 IS - 1 SP - 42 EP - 46 ER - TY - JOUR A1 - Adelmann, Benedikt A1 - Schleier, Max A1 - Hellmann, Ralf T1 - Laser Cut Interruption Detection from Small Images by Using Convolutional Neural Network JF - Sensors KW - laser cutting KW - remote sensing KW - convolutional neural network KW - cut interruption KW - image processing KW - Laserschneiden KW - Neuronales Netz Y1 - 2021 UR - https://doi.org/10.3390/s21020655 U6 - https://doi.org/10.3390/s21020655 VL - 2021 IS - 21(2) SP - 655 EP - 655 ER - TY - JOUR A1 - Adelmann, Benedikt A1 - Hellmann, Ralf T1 - Simultaneous Burr and Cut Interruption Detection during Laser Cutting with Neural Networks JF - Sensors KW - laser cutting KW - quality monitoring KW - artificial neural network KW - burr formation KW - cut interruption KW - Laserschneiden KW - Neuronales Netz Y1 - 2021 UR - https://doi.org/10.3390/s21175831 U6 - https://doi.org/10.3390/s21175831 VL - 2021 IS - 21 SP - 5831 EP - 5831 ER - TY - JOUR A1 - Schleier, Max A1 - Adelmann, Benedikt A1 - Esen, Cemal A1 - Glatzel, Uwe A1 - Hellmann, Ralf T1 - Development and evaluation of an image processing algorithm for monitoring fiber laser fusion cutting by a high-speed camera JF - Journal of Laser Applications KW - Laser cutting KW - Image processing KW - Optical imaging KW - Image sensors KW - Laser applications KW - Faserlaser KW - Laserschneiden KW - Bildverarbeitung Y1 - 2021 UR - https://doi.org/10.2351/7.0000391 U6 - https://doi.org/10.2351/7.0000391 VL - 2021 IS - 33 SP - 032004 EP - 032004 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Ultrashort pulsed laser backside ablation of fused silica JF - Optics Express KW - Femtosekundenlaser KW - Quarzglas KW - Mikrobearbeitung Y1 - 2021 VL - 29 IS - 15 SP - 23477 EP - 23486 ER - TY - JOUR A1 - Schwarz, Simon A1 - Götzendorfer, Babette A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Compact Beam Homogenizer Module with Laser-Fabricated Lens-Arrays JF - applied sciences KW - Femtosekundenlaser KW - Linse KW - Array Y1 - 2021 VL - 2021 IS - 11 SP - 1018 EP - 1018 ER - TY - JOUR A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Enhanced ablation efficiency using GHz bursts in micromachining fused silica JF - Optics Letters KW - Fräsen KW - Mikrobearbeitung KW - Quarzglas KW - Femtosekundenlaser Y1 - 2021 VL - 46 IS - 2 SP - 282 EP - 285 ER - TY - JOUR A1 - Götzendorfer, Babette A1 - Kirchgässner, Hannah A1 - Hellmann, Ralf T1 - Tunable, Anisotropic Permeability and Spatial Flow of SLM Manufactured Structures JF - Materials KW - Permeabilität KW - Selektives Laserschmelzen Y1 - 2021 U6 - https://doi.org/doi.org/10.3390/ma14185205 VL - 2021 IS - 14 SP - 5205 EP - 5220 ER - TY - CHAP A1 - Büdel, Johannes A1 - Teigelkötter, Johannes A1 - Stock, Alexander A1 - Kuhlmann, Kai A1 - Lang, Klaus A1 - Ott, Patrick T1 - Testing of High-Power Traction Batteries T2 - SMSI 2021 - System of Units and Metreological Infrastructure N2 - Electric drives in road vehicles with a battery as energy storage are about to be introduced to the mass market. In order to guarantee the quality and operational safety of battery-powered vehicles, considerable efforts must be made by car manufacturers and their suppliers. Since the properties of the batteries significantly determine the performance of the vehicles, special test benches with precise measuring systems are required for the accurate determination of the battery properties. The safety devices of the traction batteries must also be tested on high-performance test benches. In this paper the necessary test benches and the corresponding measuring systems are presented. Estimations of the measurement uncertainty and possibilities to increase measurement accuracy are presented. KW - Traktionsbatterie KW - Elektrofahrzeug Y1 - 2021 UR - https://www.ama-science.org/proceedings/details/4061 SN - 978-3-9819376-4-0 U6 - https://doi.org/10.5162/SMSI2021/C7. SP - 294 EP - 295 ER - TY - CHAP A1 - Söthje, Dominik A1 - Wehnert, Gerd A1 - Schlachter, Herbert T1 - Recycling of carbon fiber reinforced epoxy resins T2 - Abstractbook: NanoCarbon Annual Conference 2021 KW - Kohlenstofffaserverstärkter Kunststoff KW - Epoxidharz KW - Recycling Y1 - 2021 CY - Würzburg ER - TY - JOUR A1 - Söthje, Dominik A1 - Schamel, Elisabeth A1 - Schlachter, Herbert A1 - Wehnert, Gerd T1 - Chemical Recycling of Carbon Fiber Reinforced Epoxy Composites Using Mild Conditions JF - Chemie Ingenieur Technik KW - Epoxide KW - Recycling KW - Kohlenstofffaserverstärkter Kunststoff Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1002/cite.202100048 SN - 1522-2640 VL - 93 IS - 10 SP - 1 EP - 11 PB - Wiley-VCH GmbH CY - Weinheim ER - TY - CHAP A1 - Franz, Daniel A1 - Roth, Gian-Luca A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Superimposed beam deflection using acousto-optical deflectors in combination with a galvanometer scanner T2 - Lasers in Manufacturing - LiM 2021 KW - Galvanometer Y1 - 2021 ER - TY - CHAP A1 - Lutz, Christian A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Marx, Jan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Optical system for multi Bessel beam high power ultrashort pulsed laser processing using a spatial light modulator T2 - Lasers in Manufacturing - LiM 2021 N2 - We report on an optical setup for multi Bessel beam processing combining a refractive axicon and a spatial light modulator. Based on their particular beam profile, Bessel beams exhibit various advantages over conventional Gaussian beams for ultrashort pulsed laser processing. Especially for micromachining of transparent materials, applications such as micro-hole drilling or the generation of voids benefit from the increased focal length of the applied Bessel beam. In addition, on account of the significantly increased average output power of industrial ultrashort pulsed lasers over the last years, there is a high demand on multi spot applications for using the available laser power in efficient production processes. Our optical concept combines the dynamic possibilities of beam splitting using spatial light modulator with the benefits of Bessel beams facilitating multi Bessel beam processing. KW - Ultrakurzzeitlaser KW - Lichtmodulator Y1 - 2021 ER - TY - CHAP A1 - Vogl, Markus A1 - Rötzel, Peter T1 - Chaoticity Versus Stochasticity in Financial Markets T2 - International Symposium on Forecasting KW - Chaos KW - Financial Market KW - S&P500 KW - Kapitalmarkt Y1 - 2021 VL - 2021 ER - TY - JOUR A1 - Kefer, Stefan A1 - Pape, Dominik A1 - Roth, Gian-Luca A1 - Hessler, Steffen A1 - Schmauss, Bernhard A1 - Hellmann, Ralf T1 - Micromilling-assisted fabrication of monolithic polymer ridge-type waveguides with integrated photonic sensing structures JF - Optical Materials Express N2 - This study demonstrates and discusses a novel approach for the fabrication and rapid prototyping of monolithic photonic platforms comprising a ridge-type waveguide with integrated sensing structures. First, the bulk injection-molded cyclic olefin copolymer substrates are micromilled in order to define the physical extension of the ridge structure. Cross-sections down to 30 × 30 µm2, exhibiting a mean surface roughness of 300 nm, are achieved with this process. Subsequently, UV radiation is used to modify the ridge structure’s refractive index, which leads to the formation of an optical waveguide. By employing a phase mask, it is possible to equip the photonic platform with a Bragg grating suitable for temperature measurements with a sensitivity of −5.1 pm K-1. Furthermore, an integrated Fabry-Pérot cavity, generated during the micromilling step as well, enables refractive index measurements with sensitivities up to 1154 nm RIU-1. KW - Cyclic Olefin Copolymers KW - Micromilling KW - Bragg Grating KW - Fabry-Pérot Etalon KW - Bragg-Reflektor KW - Optischer Sensor Y1 - 2021 UR - https://www.osapublishing.org/ome/fulltext.cfm?uri=ome-11-8-2389&id=453071 U6 - https://doi.org/https://doi.org/10.1364/OME.425778 VL - 11 IS - 8 SP - 2389 EP - 2400 ER - TY - JOUR A1 - Kefer, Stefan A1 - Bischoff, Kay A1 - Roth, Gian-Luca A1 - Haubner, Julian A1 - Schmauss, Bernhard A1 - Hellmann, Ralf T1 - Tunable Bulk Polymer Planar Bragg Gratings Electrified via Femtosecond Laser Reductive Sintering of CuO Nanoparticles JF - Advanced Optical Materials N2 - This contribution demonstrates and discusses electrically tunable polymer planar Bragg gratings based on bulk cyclic olefin copolymers. A lithographic single-writing-step method and femtosecond laser reductive sintering of copper(II) oxide nanoparticles are subsequently employed in order to generate buried photonic structures and copper conducting paths on top of the polymer substrate. This way, the necessary number of process steps for fabricating a planar polymer-based electro-optical device is greatly reduced. The response of a fully electrified grating structure follows temperature changes, induced by the copper conducting path, with sensitivities up to −31 pm K−1. Dilatometric measurements show that the specimen's behavior is correlated to the situationally reduced thermal expansion of the bulk polymer substrate. In consequence, the tuning response of the photonic platform follows a second order polynomial, whereas a direct current of 30 mA, which correlates to a power consumption of 18.3 mW, leads to a local temperature increase and a residual Bragg wavelength shift of 19.6 K and −547 pm, respectively. Moreover, the outstanding flexibility of the proposed fabrication concept is underlined by demonstrating alternative conducting path geometries, whereas one of the additional designs is adapted to control the spectral width of the Bragg grating's reflection peak. KW - Bragg gratings KW - CuO nanoparticles KW - cyclic olefin copolymers KW - electro-optic tuning KW - integrated photonics KW - Femtosekundenlaser KW - Bragg-Reflektor Y1 - 2021 UR - https://onlinelibrary.wiley.com/doi/10.1002/adom.202002203 U6 - https://doi.org/https://doi.org/10.1002/adom.202002203 VL - 9 IS - 13 SP - 2002203 EP - 2002203 ER - TY - GEN A1 - Kefer, Stefan A1 - Bischoff, Kay A1 - Roth, Gian-Luca A1 - Haubner, Julian A1 - Schmauss, Bernhard A1 - Hellmann, Ralf T1 - Tunable Bulk Polymer Planar Bragg Gratings Electrified via Femtosecond Laser Reductive Sintering of CuO Nanoparticles (Advanced Optical Materials 13/2021) N2 - This cover image outlines the fabrication method of a polymer planar Bragg grating electrified via femtosecond laser reductive sintering of CuO nanoparticles (see article number 2002203 by Stefan Kefer and co-workers). Based on this sophisticated methodology, bulk cyclic olefin copolymer substrates can be equipped with integrated photonic structures comprising a waveguide as well as a Bragg grating. Its reflective characteristics can be efficiently tuned by means of the subsequently generated Cu conducting path, whereas the applied femtosecond laser process enables an almost limitless degree of freedom towards conducting path geometries. N2 - Cover zum zugehörigen Artikel KW - Femtosekundenlaser KW - Bragg-Reflektor Y1 - 2021 UR - https://onlinelibrary.wiley.com/doi/10.1002/adom.202170048 U6 - https://doi.org/https://doi.org/10.1002/adom.202170048 ER - TY - JOUR A1 - Herzog, Anna Laura A1 - Jouanne-Diedrich, Holger K. von A1 - Wanner, Christoph A1 - Weismann, Dirk A1 - Schlesinger, Tobias A1 - Meybohm, Patrick A1 - Stumpner, Jan ED - Serra, Raffaele T1 - COVID-19 and the kidney: A retrospective analysis of 37 critically ill patients using machine learning JF - Plos one N2 - Introduction There is evidence that SARS-CoV2 has a particular affinity for kidney tissue and is often associated with kidney failure. Methods We assessed whether proteinuria can be predictive of kidney failure, the development of chronic kidney disease, and mortality in 37 critically ill COVID-19 patients. We used machine learning (ML) methods as decision trees and cut-off points created by the OneR package to add new aspects, even in smaller cohorts. Results Among a total of 37 patients, 24 suffered higher-grade renal failure, 20 of whom required kidney replacement therapy. More than 40% of patients remained on hemodialysis after intensive care unit discharge or died (27%). Due to frequent anuria proteinuria measured in two-thirds of the patients, it was not predictive for the investigated endpoints; albuminuria was higher in patients with AKI 3, but the difference was not significant. ML found cut-off points of >31.4 kg/ m2 for BMI and >69 years for age, constructed decision trees with great accuracy, and identified highly predictive variables for outcome and remaining chronic kidney disease. Conclusions Different ML methods and their clinical application, especially decision trees, can provide valuable support for clinical decisions. Presence of proteinuria was not predictive of CKD or AKI and should be confirmed in a larger cohort. KW - COVID-19 KW - Maschinelles Lernen KW - Niereninsuffizienz Y1 - 2021 UR - https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0251932 U6 - https://doi.org/https://doi.org/10.1371/journal.pone.0251932 VL - 2021 IS - Online/2021 SP - 1 EP - 15 ER - TY - RPRT A1 - Rock, Verena A1 - Brehm, Nadine A1 - Schlesinger, Sarah A1 - Liebold, Philipp J. T1 - PropTech Germany 2021 Studie T2 - PropTech Germany Studien N2 - PropTech-Charakteristika Die 185 teilnehmenden PropTechs sind den Reifegrad-Clustern Early Stager (19,5%), Grown Ups (57,8%) und Conquerer (22,7%) zuzuordnen. 48% der Prop-Techs sind sehr junge Unternehmen mit den Gründungsjahren 2018 - 2020. Durchschnittlich liegen 1,6 Jahre zwi-schen Gründung des Unternehmens und Launch des Produktes. Jeweils die Mehrheit der Teilnehmer bedient ausschließlich das B2B-Segment (80,0%), operiert mit weniger als 15 Mitarbeitern (65,4%) und befindet sich im Produkt-Entwicklungsstadium des laufenden Betriebs (70,8%). Die Spanne der von den PropTechs erzielten Umsätze ist weit. Korrespondierend mit dem “jungen” Unternehmensalter erzielten 29,7% der PropTechs nur bis zu 10.000€ Jahresumsatz in 2020. Jedoch geben an-dererseits 16,2% der Befragten einen Jahresumsatz von über 1 Mio. € an. Technologisch überwiegt die Plattformtechnologie in allen Lebenszyklusphasen. Als Einnahmenmodell existieren mehrheitlich Subscription- oder Lizenz-vereinbarungen, und eine laufende monatliche oder jährliche Gebühr wird meist als Preismodell genutzt. Schnittstellen verschiedenen Typs sind bereits bei 73,0% der PropTechs verfügbar. PropTechs im Immobilien-Lebenszyklus In der Immobilienwertschöpfungskette bedient das Gros der Teilnehmer den Betrieb die Bewirtschaftung von Immo-bilien, wobei jedoch im Durchschnitt 3,2 Lebenszyklusphasen von den Prop-Techs bedient werden. Somit bewegen sie sich tendenziell nicht in den tradierten Grenzen und Prozessen der Immo-bilienwirtschaft. Die meisten PropTechs mit hohen Umsätzen sind in der Be-wirtschaftung oder Vermarktung von Immobilien aktiv. Als Assetklasse dominiert klar Wohnen, gefolgt von Büro und Mixed-Use, wobei aber ein Prop-Tech durchschnittlich 4,3 Assetklassen bedient. Im Wohnsegment dominieren jedoch die PropTechs mit noch sehr geringen Umsätzen. Hier herrscht auch der höchste B2C Anteil der Assetklassen vor. Nur 20,5% der PropTechs legen sich auf eine Assetklasse fest. Aktuelle Lage des deutschen PropTech-Marktes Für das Jahr 2020 empfinden die Prop-Techs die Auftragslage als äußerst posi-tiv, und auch der mittelfristigen Entwicklung der Jahre bis Ende 2023 blickt eine überwältigende Mehrheit positiv entgegen. So verzeichneten in 2020 70,8% der PropTechs mehr Neugeschäft, davon 35,9% deutlich mehr Neugeschäft. Für 2021 bis 2023 erwarten 52,4% der PropTechs deutlich mehr Neugeschäft und insgesamt über 91,4% sehen positive Vorzeichen für die Marktentwicklung. Hinsichtlich des Corona-Effekts konn-ten die Unternehmen mehrheitlich eher von der Pandemie profitieren; für die Zukunft ergibt sich ein aus ihrer Sicht noch positiveres Bild. Ganze 66,5% erwarten zukünftig eine Zunahme ihres Geschäftes durch Corona und weitere 26,0% sehen keine Auswirkungen. Lediglich 7,6% erwarten pandemiebedingt eine Abnahme des eigenen Geschäfts. Nach eigenen Einschätzungen gehören PropTechs also mehrheitlich zu den Gewinnern der Pandemie. Herausforderungen für PropTechs im deutschen Immobilienmarkt In der Studie wurden drei Phasen des proptechseitigen Vermarktungsprozesses untersucht: Aufbau des Geschäftsmodells, Produktverkauf und Implemen-tierung. Die Phase des Produktverkaufs ist für 53% der PropTechs die hürden-reichste Phase deutlich vor dem Aufbau des Geschäftsmodells und Implementierung beim Kunden. Die wesentlichen Herausforderungen beim Aufbau des Geschäftsmodells sind für alle Prop-Tech-Cluster die Entscheidungsstrukturen beim Kunden, gefolgt von dem geringen Druck zur Digitalisierung in der Immobilienbranche und Produktentwicklungskosten sowie der Zugang zu Daten, wobei dieser für Early Stager am schwierigsten erscheint. In der Phase des Produktverkaufs zeigt sich, dass die größte Hürde in der geringen Risikobereitschaft des Establishments, in Technologien von PropTechs zu investieren, liegt - gepaart mit mangelndem Vertrauen und einem mangelnden Verständnis in Bezug auf die Technologie sowie das Potenzial der Produkte. Weiterhin liegt im schwierigen Zugang zum richtigen Ansprechpartner eine wesentliche Verkaufshürde. Hier ergibt sich aus Sicht der PropTechs, dass die operativ verantwortliche Fach-abteilung im Establishment, in der das Produkt angewendet würde, der wesentliche Influencer für die Kaufentscheidung ist. Als relevantester Ent-scheider wird hingegen mehrheitlich der CEO gesehen. Dies kann ein Hinweis darauf sein, dass Digitalisierungsent-scheidungen immer noch auf strategischer Ebene getroffen werden. Prop-Techs, die es bei einem Kunden bis zur Implementierung geschafft haben, sind über den Berg der Hürden und sehen sich fortan nur moderateren Herausforderungen gegenüber. Von diesen sind die mangelnde Priorität des Projektes auf Kundenseite sowie fehlende C-Level-Sponsorship bzgl. der Durchsetzung von Entscheidungen die wesentlichen Herausforderungen. Somit sehen sich PropTechs mit wenig Unerwartetem bei der Implementierung konfrontiert, dürfen aber auch keine Priorität und Unterstützung vom Kunden erwarten. Kooperationen Kooperationen zwischen PropTechs sind überwiegend technischer Natur und haben einen hohen Stellenwert; 71,9% der Bef ragten haben bereits horizontale oder vertikale Kooperationen. Ziele sind hier meist Umsatz-, Netzwerk- und Zielgruppenerweiterung. Die Kooperationsbereitschaft nimmt mit steigendem Reifegrad der PropTechs zu; am ausgeprägtesten ist sie bei Conquerers, wo Kooperationen als Vorteil des Markteintritts nach Deutschland interpretiert werden können. Durch vertikale Kooperationen können PropTechs den Kunden ein er-weitertes bzw. kompletteres Lösungs-portfolio sowie teilweise eine deutlich breitere Anzahl an Use Cases anbieten. Damit einhergehend stehen auch die Themen Ökosystem und Plattformen. PropTechs können mittels Partnerschaften / Kooperationen einen größeren Teil der Wertschöpfungskette abbilden, ihre Angebote bündeln und somit „one stop shop” Lösungen für die Kunden anbieten. KW - Immobilienwirtschaft KW - Digitalisierung Y1 - 2021 UR - https://www.iiwm.de/wp-content/uploads/2021/03/PropTech-Germany-2021-Studie-2.pdf ER - TY - CHAP A1 - Cotroneo, Vincenzo A1 - Bruni, Ricardo A1 - Döhring, Thorsten A1 - Ferreira, Desiree A1 - Gibertini, Eugenio A1 - Henriksen, Peter A1 - Magagnin, Luca A1 - Massahi, Sonny A1 - Pareschi, Giovanni A1 - Romaine, Suzanne A1 - Sethares, Leandra A1 - Sironi, Giorgia A1 - Spiga, Daniele A1 - Tagliaferri, Gianpiero A1 - Valsecchi, Giuseppe T1 - Development of low-density coatings for soft x-ray reflectivity enhancement for ATHENA and other missions T2 - Proceedings of SPIE N2 - Metallic coatings made of precious metals (e.g. Ir, Pt or Au) with high atomic number Z have been traditionally employed at grazing incidence for X-rays reflection and focalization. These materials offer a range of reflection extended to higher energies, but also present a series of absorption edges, which limit the reflectivity in the 2-4 keV band and below. Therefore the search for alternative coatings, able to improve the reflection in the soft energy range, is particularly relevant for the development of future telescopes, like ATHENA (ESA), Lynx (NASA) and eXTP (CAS). Low-Z overcoatings (e.g. carbon or B4C), applied on top of the high-Z metallic layer, can enhance the reflectivity in the softer band (mainly below 2 keV), but conventional deposition methods for these materials are not easily compatible with some of the mainstream technologies for mirror fabrication (notably, the silicon pore optics that will be used for the ATHENA X-ray mission which is being implemented by ESA). In this work we discuss novel solutions (carbon-like overcoatings realized by dip coating or vapor phase deposition), which can be particularly convenient for the application to ATHENA and to future telescopes. KW - X-ray KW - optics KW - ATHENA KW - iridium KW - reflectivity KW - Röntgenteleskop Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1117/12.2599803 VL - 2021 IS - 11852 SP - 118524P-1 EP - 118524P-13 PB - SPIE ER - TY - RPRT A1 - Neeb, Nora A1 - Schöne, Lars Bernhard T1 - Investmentmarkt für Logistikimmobilien im Kontext der Covid-19-Pandemie T2 - IIWM-Paper No. 7: Schriftenreihe des IIWM Institut für Immobilienwirtschaft und -management N2 - Dieses Arbeitspapier beschäftigt sich mit der Analyse des Investmentmarktes für Logistikimmobilien mit der Fokussierung auf die Covid-19-Pandemie. Zentrales Ziel der Schrift ist es, den Investmentmarkt für Logistikimmobilien und die Auswirkungen, die die Covid-19-Pandemie auf diesen genommen hat, zu analysieren. Dabei werden die (Mega-)Trends auf welche die Pandemie Einfluss genommen hat, beleuchtet. Weiterhin werden wichtige Marktkennzahlen eines Investmentmarktes definiert. Diese Kennzahlen, sowie weitere essentielle Marktparameter dienen anschließend der Marktanalyse des Jahres 2019. Darauf folgt eine detaillierte Betrachtung der Marktentwicklung 2020 – dem Covid-Jahr. Hierbei werden die vier Quartale gesondert analysiert um etwaige Veränderungen erkennen zu können. Im Fazit erfolgt eine ausführliche Zusammenfassung der aktuellen Stimmung auf dem Logistikinvestmentmarkt und es wird ein vorsichtiger Blick auf künftige Entwicklungen geworfen. KW - Gewerbeimmobilien KW - Logistikunternehmen KW - COVID-19 Y1 - 2021 UR - https://www.iiwm.de/wp-content/uploads/2021/06/IIWM-Paper-No-7-Logistik-Neeb_Schoene-ISSN2568-5872.pdf ER - TY - CHAP A1 - Kefer, Stefan A1 - Roth, Frederick A1 - Kaloudis, Michael A1 - Schmauss, Bernhard A1 - Hellmann, Ralf T1 - Monitoring of Composite Bicycle Components using Polymer Planar Bragg Gratings T2 - SMSI 2021 - Sensors and Instrumentation N2 - This study demonstrates mobile load monitoring of a composite bicycle component using an application- customized polymer planar Bragg grating sensor, evaluated by a mobile interrogation unit. After a referencing procedure, the mechanical load of a seat post is monitored while cycling through a test track. KW - Bragg Grating KW - Composites KW - Cyclic Olefin Copolymers KW - Micromilling KW - Load Monitoring KW - Bragg-Reflektor KW - Verbundwerkstoff KW - Fahrrad Y1 - 2021 UR - https://www.ama-science.org/proceedings/details/3992 SN - 978-3-9819376-4-0 U6 - https://doi.org/10.5162/SMSI2021/B9.2 SP - 161 EP - 162 PB - AMA Service GmbH CY - Wunstorf, Germany ER - TY - CHAP A1 - Stehlikova, Veronika A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Stadtmüller, Johannes A1 - Marsikova, Veronika A1 - Hudec, Rene A1 - Flachs, Dennis A1 - Burwitz, Vadim A1 - Hartner, Gisela A1 - Rukdee, Surangkhana A1 - Müller, Thomas A1 - Schmidt, Thomas A1 - Inneman, Adolf A1 - Klementova, Mariana A1 - Zeising, Sebastian A1 - Langmeier, Andreas T1 - Lobster eye type X-ray telescope with chromium-iridium coated tri-layer mirrors T2 - Proceedings of SPIE N2 - For space-born astronomical X-ray telescopes, iridium-based reflective layer systems are known as highly effective mirrors coatings. During the recent years, Aschaffenburg University of Applied Sciences and the Czech Technical University in Prague jointly developed stress compensated chromium-iridium coatings for this application. To overcome the disturbing reflectivity reduction of the iridium absorption edge around 2 keV photon energy, thin overcoat layers of chromium were applied in addition. Now a prototype of a wide-field, imaging X-ray telescope of Lobster Eye type is assembled at the company RIGAKU. For this purpose a small series of 34 mirrors based on 100 x 50 mm semiconductor grade silicon substrates has been coated at Aschaffenburg University. The applied tri-layer system consists of a stack of 40 nm chromium, which act as adhesive layer and compensates layer stress, a 30 nm iridium thick reflective layer, and an additional overcoat layer of 6 nm chromium. This layer system have been analysed by AFM and TEM images. The mirrors are assembled into an aluminium frame to build a 2D Lobster Eye type telescope. The designed focal length of this wide field X-ray telescope is two meter. To study the performance of the tri-layer coating system, a twin LE telescope with convenient gold coatings was manufactured also. Performance measurements of both telescopes and under same conditions are planned at the PANTER test facility at the Max-Planck Institute for Extraterrestrial Physics. First experimental results, their comparison with theoretical simulations and the comparison between both models will be presented in this contribution. KW - telescope KW - Lobster Eye KW - X-ray KW - mirror KW - iridium KW - Röntgenteleskop KW - Röntgenspiegel Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1117/12.2589266 VL - 2021 IS - 11776 SP - 1177605-1 EP - 1177605-8 PB - SPIE ER - TY - CHAP A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Stadtmüller, Johannes A1 - Zeising, Sebastian A1 - Flachs, Dennis A1 - Stehlikova, Veronika A1 - Burwitz, Vadim A1 - Krumrey, Michael K. A1 - Cotroneo, Vincenzo A1 - Klementova, Mariana T1 - Characterisation of X-ray mirrors based on chromium-iridium tri-layer coatings T2 - Proceedings of SPIE N2 - Iridium-based layer systems are highly effective mirror coatings for space-born X-ray telescopes. During the recent years, Aschaffenburg University of Applied Sciences and its partners developed stress compensated chromium-iridium coatings for such astronomical applications, using chromium as an adhesive layer between iridium reflective layer and mirror substrate. However, there was room for improvement: To overcome the disturbing reflectivity reduction of the iridium absorption edge around 2 keV photon energy, thin overcoat layers of chromium are applied in addition now. This layer system has been analyzed by atomic force microscopy and transmission electron microscopy images. Furthermore, the reflectivity of such innovative X-ray mirrors based on chromium-iridium tri-layer coatings was recently measured at PTB's four-crystal monochromator beamline at the synchrotron radiation facility BESSY II. The experimental results, obtained for photon energies between 1.9 keV and 11 keV at two grazing incidence angles (0.6 degree and 0.9 degree) and their comparison with corresponding simulations are presented in this contribution. When compared to simulations of pure iridium coatings, a significantly higher reflectivity was achieved especially in the soft X-ray regime between 2 keV and 4 keV. Such chromium-iridium tri-layer coatings have high potential to increase the effective area for X-ray telescopes in Lobster Eye Design, for Wolter-I type X-ray optics, and for silicon pore optics as considered for the ATHENA telescope of the European Space Agency. KW - iridium KW - mirror KW - X-ray KW - coating KW - telescope KW - Röntgenspiegel KW - Röntgenteleskop KW - Iridium Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1117/12.2592551 VL - 2021 IS - 11776 SP - 1177607-1 EP - 11776076 PB - SPIE ER - TY - GEN A1 - Döhring, Thorsten T1 - Advanced Materials and Manufacturing Technologies for Space Applications T2 - Proceedings of International Research Days N2 - The goal of this project is to develop satellite components for space-based astronomical satellite payloads. Thereby advanced materials like iridium and innovative manufacturing technologies will be applied. After environmental testing and space qualifications tests it is planned to do an astronomical experiment with a stratospheric balloon or a sounding rocket. The work is embedded in ACCASI („Aschaffenburg Competence Center for Astronomical and Space Instumentation“) N2 - Poster KW - satellite KW - iridium KW - telescope KW - mirror KW - Satellitentechnik KW - Iridium KW - Spiegelteleskop Y1 - 2021 VL - 2021 ER - TY - GEN A1 - Licciardello, Nadia A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Kolen'ko, Yury V. A1 - Petrovykh, Dmitri Y. T1 - Innovative nanocomposite coatings for radiation shielding on satellites T2 - EuroNanoForum N2 - The current trend in development of low-cost satellites is based on small dimensions combined with advanced electronics. Traditionally, radiation-sensitive electronics on satellites are protected by tungsten or lead foils, which are high-density materials and contribute significantly to the overall mass of the satellite. Here, we design and investigate temperature-gradient-resistant lightweight silane-based composites containing micro- or nano-particles of W or WO3, taking inspiration from similar approaches in the medical field. While the polymeric matrix provides flexibility under thermal gradients (such as those occurring in satellites during their orbits) and low density, the particles enable shielding from soft X-rays and other radiation. For reference, thin tungsten films were deposited by magnetron sputtering. The properties of the two kinds of coatings were compared and the X-ray protective properties were investigated using both a custom-designed measurement setup and conventional X-ray absorption. The best performing radiation-protective coatings will be launched in a payload experiment on the INFANTE satellite. N2 - Poster KW - satellite KW - polymeric matrix KW - nanocomposite KW - radiation protection KW - Satellitentechnik KW - Strahlung Y1 - 2021 UR - https://euronanoforum2021.eu/ VL - 2021 ER - TY - GEN A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Stadtmüller, Johannes A1 - Freudenmann, Dominic A1 - Röcke, Nicole T1 - Nanostructured iridium catalysts for effective hydrogen peroxide decomposition T2 - EuroNanoForum N2 - The EU intends to restrict the use of critical fuels in space propulsion systems. These propellants like hydrazine are chemically aggressive, toxic and carcinogenic. Space propulsion of the future should be environmentally friendly, inexpensive, and easy to handle. Aschaffenburg University and DLR are currently developing environmentally friendly technologies for future satellite engines. Thereby rocket-grade hydrogen peroxide, which is foreseen as a substitute, is converted to uncritical water vapour and oxygen by an exothermic catalytic reaction on nanostructured iridium layers. The resulting hot gases provide the required amount of thrust. The iridium catalyst layers are coated onto ceramic pellets, using RF magnetron sputtering technology. The catalytic functionality was tested afterwards at the chemical laboratories of DLR. First experimental results show a significantly higher catalytic activity for nanostructured iridium surfaces than for smoother crystalline layers. N2 - Poster KW - satellite KW - propulsion KW - catalyst KW - iridium KW - hydrogen peroxide KW - Iridium KW - Katalysator KW - Satellitentechnik Y1 - 2021 VL - 2021 ER - TY - CHAP A1 - Fehrenbacher, Dennis A1 - Rötzel, Peter A1 - Choo, Kim-Kwang Raymond T1 - Sentiment Analysis of Cyber-Attack Incident Reports T2 - ICIS 2021 N2 - This article examines sentiment of 12,821 reports on cyber-attacks on firms around the world from 2011 to mid-year 2019. With theworld wide web (www) and associated technologies connecting opinions worldwide, sentiment in the world wide web is an importantperspective to understanding developments in cyber-attacks and the public opinion thereof, because much of the public debate isshared online. Such sentiment can potentially explain developments in regulation and may be indirectly associated with the buildingof defense mechanisms of cyber-victims. Results show that the quantity of reports on cyber-attacks on firms has been increasing,but the sentiment of reports on cyber-attacks has been decreasing. Both trends reflect the increasing severity of the issue and arelikely contributing to regulatory responses. Results also show that the sentiment is conditional to the source that reports the cyber-attack. KW - Cyber Risk KW - Natural Language Processing KW - Information Systems KW - Cyber Security KW - Cyberattacke KW - Unternehmen KW - Computersicherheit Y1 - 2021 VL - 2021 ER - TY - CHAP A1 - Döhring, Thorsten A1 - Stritzelberger, Carolyn A1 - Mues, Kristin A1 - Schäfer, Kerstin A1 - Rosendahl, Wilfried A1 - Busch, Uwe T1 - Celebrating the Röntgen anniversary year: pupil experiments at Aschaffenburg University T2 - SPIE Proceedings N2 - On November 8th, 1895, Professor Wilhelm Conrad Röntgen was still working late on cathode rays in his laboratory at the University of Würzburg in Germany. By chance, he found a new type of radiation that was able to penetrate materials. He himself called them X-rays. In his honour, in Germany we call this type of radiation Röntgen´s rays since 1896. In 2020, Germany was celebrating the Röntgen anniversary year, recognizing the discovery of X-rays 125 years ago and the 175th birthday of its discoverer Wilhelm Conrad Röntgen, the first Nobel laureate in physics. Financed by a grant from the Klaus Tschira Foundation, the Reiss-Engelhorn-Museums in Mannheim and the German Röntgen Museum in Remscheid developed an “X-periments mobile” with interactive experiments for children and young people. Following the given motto "X-periments - making the invisible visible", this research station with optical experiments started traveling across Germany in the anniversary year and, due to the corona pandemic in the following year. In summer 2021, the “X-periments mobile” will make a guest appearance at Aschaffenburg University. The experimental set-ups enable school classes and students to gain an overview of optical technologies from infrared light to ultraviolet radiation to X-rays and gamma rays. The aim of the campaign is to inspire the young generation and to attract students for courses in science and technology. This contribution presents the historical discovery of X-rays, the “X-periments mobile” and its experiments, its intention, and the experiences from its stays at different places across Germany. KW - x-ray KW - Röntgen KW - education KW - Röntgen, Wilhelm Conrad, 1845-1923 KW - Jubiläum KW - Schülerversuch Y1 - 2021 UR - https://doi.org/10.1117/12.2589142 U6 - https://doi.org/https://doi.org/10.1117/12.2589142 VL - 2021 IS - 11776 SP - 117760E-1 EP - 117760E-10 PB - SPIE ER - TY - JOUR A1 - Smeets, Mario A1 - Ostendorf, Ralf A1 - Rötzel, Peter T1 - AI and its Opportunities for Decision Making in an Organizational Context: A Systematic Review of the Influencing Factors on the Intention to use AI JF - Die Unternehmung – Swiss Journal of Business Research and Practice N2 - One domain of application of artificial intelligence (AI) is decision support, particularly in management. Although there are already research streams examining the interaction of AI and humans (e.g. the stream on "hybrid intelligence"), there are still numerous open research gaps – for example, a comprehensive overview of which factors favor the intention to use AI is missing. By conducting a systematic literature review, we identify the factors that potentially positively influence AI usage intentions for decision-making processes in organizations. From this, we create a framework that both provides practical implications for the successful use of AI in organizational decision-making processes and delivers further research approaches, for example, on the validity/ usability of proven IS adoption models in the present context. KW - Artificial Intelligence KW - Decision-making KW - Management Control KW - information systems KW - information management KW - Künstliche Intelligenz KW - Entscheidungsfindung KW - Management Y1 - 2021 VL - 2021 IS - OnlineFirst SP - 1 EP - 28 ER - TY - CHAP A1 - Voigt, Jorrit A1 - Möckel, Michael ED - Chinesta, R. ED - Abgrall, R. ED - Allix, O. ED - Kaliske, M. T1 - Comparing principal component analysis (PCA) and 𝛃-variational autoencoder(𝛃-VAE)for anomaly detection in selective laser melting (SLM) process data T2 - 14th WCCM-ECCOMAS Congress 2020, virtual congress, January, 11-15, 2021 N2 - The usability of machine learning approaches for the development of in-situ process monitoring, automated anomaly detection and quality assurance for the selective laser melting (SLM) process receives currently increasing attention. For a given set of real machine data we compare two established methods, principal component analysis (PCA) and -variational autoencoder (-VAE), for their applicability in exploratory data analysis and anomaly detection. We introduce a PCA-based unsupervised feature extraction algorithm, which allows for root cause analysis of process anomalies. The -VAE enables a slightly more compact dimensionality reduction; we consider it an option for automated process monitoring systems. KW - Anomaly detection KW - Process monitoring KW - additive manufacturing KW - Selektives Laserschmelzen KW - Anomalie Y1 - 2021 UR - https://www.scipedia.com/public/Voigt_Moeckel_2021a U6 - https://doi.org/10.23967/wccm-eccomas.2020.144 SP - 1 EP - 9 ER - TY - CHAP A1 - Zindler, Klaus A1 - Sauer, Timm T1 - Self learning control for automatic track guidance T2 - Proceedings of International Research Days KW - automatic track guidance KW - self learning control KW - Artificial Intelligence KW - automated vehicle guidance KW - Autonomes Fahrzeug Y1 - 2021 VL - 2021 SP - 64 EP - 64 ER - TY - CHAP A1 - Zindler, Klaus T1 - Welcome & Key Research Areas of Aschaffenburg University of Applied Sciences T2 - Proceedings of International Research Days KW - Key Research Areas KW - Hochschule Aschaffenburg KW - Forschung Y1 - 2021 ER - TY - JOUR A1 - Döhring, Thorsten ED - IHK Aschaffenburg, T1 - Forscher entwickeln umweltfreundliche Satellitenantriebe JF - Wirtschaft am Bayerischen Untermain N2 - In der aktuellen Förderrunde des vom Bayerischen Staatsministeriums für Wissenschaft und Kunst aufgesetzten „Programms zur Förderung der angewandten Forschung und Entwicklung an Hochschulen für angewandte Wissenschaften – Fachhochschulen“ war die Technische Hochschule Aschaffenburg sehr erfolgreich. Für das Technologieprojekt ACCASI („Aschaffenburg Competence Center for Astronomical and Space Instrumentation“) erhält sie über eine Laufzeit von drei Jahren insgesamt 250.000 Euro. KW - Satellit KW - Triebwerk KW - Iridium KW - Katalysator KW - Satellitentechnik Y1 - 2021 UR - https://www.aschaffenburg.ihk.de/share/flipping-book/5064860/flippingbook.pdf VL - 2021 IS - März SP - 12 EP - 13 ER - TY - JOUR A1 - Butz-Seidl, Annemarie T1 - Vorbehaltsnießbrauch an GmbH-Anteilen: Gestaltungsempfehlungen in der Praxis JF - Erbfolgebesteuerung N2 - Der Nießbrauch an GmbH-Beteiligungen ist eine in der Praxis beliebte Gestaltungsform, die regelmäßig eine flexible Zuweisung von Vermögenssubstanz auf der einen und den daraus fließenden Erträgen auf der anderen Seite ermöglicht. Ja nach Zielsetzung werden unterschiedliche Nießbrauchsmodelle gewählt. Der Vorbehaltsnießbrauch wird häufig zur Gestaltung der Unternehmensnachfolge genutzt, während der Zuwendungsnießbrauch auf die Versorgung von Angehörigen im Rahmen der vorweggenommenen Erbfolge abzielt. Dieser Beitrag beschäftigt sich mit der Variante 1. In einem Folgebeitrag wird der Zuwendungsnießbrauch als Gestaltungsmodell auf den Prüfstand gestellt. KW - Vorbehaltsnießbrauch KW - GmbH KW - Gesellschaftsanteil KW - Nießbrauch KW - GmbH-Beteiligung KW - Unternehmensnachfolge KW - Gestaltungsempfehlungen KW - Zivilrecht KW - Einkommensteuerrecht KW - Schenkungsteuerrecht KW - Musterfall Y1 - 2021 VL - 2021 IS - 4 SP - 98 EP - 104 ER - TY - CHAP A1 - Gold-Veerkamp, Carolin T1 - Validated Undergraduates’ Misconceptions about Software Engineering T2 - Global Engineering Education Conference (EDUCON) KW - Software Engineering Y1 - 2021 PB - IEEE ER - TY - RPRT A1 - Vogl, Markus A1 - Rötzel, Peter T1 - Chaoticity Versus Stochasticity in Financial Markets: Are Daily S&P 500 Return Dynamics Chaotic? N2 - In this study, we present a combinatory chaos analysis of daily wavelet-filtered (denoised) S&P 500 returns (2000–2020) compared with respective surrogate datasets, Brownian motion returns and a Lorenz system realisation. We show that the dynamics of the S&P 500 return series consist of an almost equally divided combination of stochastic and deterministic chaos. The strange attractor of the S&P 500 return system is graphically displayed via Takens’ embedding and by spectral embedding in combination with Laplacian Eigenmaps. For the field of nonlinear and financial chaos research, we present a bibliometric analysis paired with citation network analysis. We critically discuss implications and future prospects. KW - nonlinear dynamics KW - chaos KW - recurrence analysis KW - finance KW - financial market KW - Kreditmarkt KW - Chaostheorie Y1 - 2021 UR - https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3802753 ER - TY - JOUR A1 - Lutz, Christian A1 - Roth, Gian-Luca A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Efficient Ultrashort Pulsed Laser Processing by Dynamic Spatial Light Modulator Beam Shaping for Industrial Use JF - Journal of Laser Micro/Nanoengineering N2 - We report on the effect of different transversal beam shapes on the efficiency of ablation processes and the resulting surface characteristics. A possibility to efficiently apply ultrashort pulsed lasers with high average power is beam shaping. By using a cooled reflective based liquid crystal spatial light modulator to generate different spot distributions, it is possible to spatially allocate the available power to avoid excessive high fluences. In our experiments, we determine the optimal fluence to ablate the maximum volume per watt to be in the range of 0.2-0.4 J/cm². Based on this fluence, we increase the number of spots from one to a maximum of twenty to ablate steel in a multilayer scanning-based process. In this context, we examine the influence of different separation distances between the spots on the ablation efficiency and roughness. Subsequently to these investigations, we develop an efficient roughing process with higher ablation rates and a nearly constant roughness. KW - Ultrakurzzeitlaser KW - Lichtmodulator Y1 - 2021 U6 - https://doi.org/10.2961/jlmn.2021.01.2011 VL - 16 IS - 1 SP - 1 EP - 6 ER - TY - JOUR A1 - Stollenwerk, Manfred A1 - Döhring, Thorsten A1 - Freudenmann, Dominic A1 - Schäfer, Tobias A1 - Stadtmüller, Johannes A1 - Röcke, Nicole T1 - Sputtered highly effective iridium catalysts: a new approach for green satellite propulsion JF - Journal of Materials Science N2 - This work demonstrated the large potential of sputtered iridium metal for catalytic reactions shown by the example of decomposition of hydrogen peroxide (H2O2) for space propulsion systems. For this purpose, iridium was coated onto Al2O3 pellets by a sputter process under varied process parameters. Depending on previously selected parameters, the obtained metal-loaded pellets offer closed- and/or open-shell structures. Catalytic productivity of these first-generation iridium-sputtered catalysts was estimated in laboratory experiments and compared to platinum-loaded pellets. Under optimized sputter-process conditions, the reactivity is significantly improved compared to the platinum-impregnated pellets. The better catalytic productivity can be explained by the increased active surface area of the iridium layers on the pellets. The surface morphology and the microstructure of the iridium coating can be actively controlled by the sputter pressure. The results are in accordance with the sputtering process pressure tendency described by the Thornton Structure–Zone Model. KW - Iridium KW - Katalysator KW - Satellitentechnik Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1007/s10853-021-05897-z VL - 2021 IS - 2021 SP - 1 EP - 11 ER - TY - RPRT A1 - Jost, Thomas A1 - Seitz, Franz T1 - Designing a European Monetary Fund: What role for the IMF? T2 - Institute for Monetary and Financial Stability, Working Paper Series No. 151 (2021) N2 - The so-called Troika, consisting of the EU-Commission, the European Central Bank (ECB) and the International Monetary Fund (IMF), was supposed to support the member states of the euro area which had been hit hard by a sovereign debt crisis. For that purpose, economic adjustment programs were drafted and monitored in order to prevent the break-up of the euro area and sovereign defaults. The cooperation of these institutions, which was born out of necessity, has been partly successful, but has also created persistent problems. With the further increase of public debt, especially in France and Italy, the danger of a renewed crisis in the euro area was growing. The European Stability Mechanism (ESM) together with the (strongly politicized) European Commission will replace the Troika in the future, following decisions of the EU Summit of December 2018. It shall play the role of a European Monetary Fund in the event of a crisis. The IMF, on the other side, will no longer play an active role in solving sovereign debt crises in the euro area. The current course is, however, inadequate to tackle the core problems of the euro zone and to avoid future crises, which are mainly structural in nature and due to escalating public debt and lack of international competitiveness of some member countries. The current Corona crisis will aggravate the institutional problems. It has led to a common European fiscal response ("Next Generation EU"). This rescue and recovery program will not be financed by ESM resources and will not be monitored by the ESM. One important novelty of this package is that it involves the issuance of substantial common European debt. KW - Europäische Union KW - Internationaler Währungsfonds KW - Schuldenkrise KW - Öffentliche Schulden KW - euro area, European Monetary Fund, International Monetary Fund, euro crisis, European Stability Mechanism Y1 - 2021 ER - TY - JOUR A1 - Roth, Gian-Luca A1 - Kefer, Stefan A1 - Hessler, Steffen A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Integration of Microfluidic and Photonic Components within Transparent Cyclic Olefin Copolymers by Using fs Laser JF - Journal of Laser Micro/Nanoengineering N2 - In this study, we report on the integration of microfluidic channels and optical components by focusing femtosecond laser radiation inside transparent cyclic olefin copolymer (COC) bulk material. An internal localized material modification is triggered based on nonlinear absorption of the laser radiation's high intensities inside the focal volume. The size and shape of the three-dimensional internal modification are controlled by using an adaptive beam shaping setup. The irradiated areas show a positive refractive index shift and can be used as Type I internal optical waveguides. Furthermore, precise control of the spatial pulse-to-pulse distance in combination with a suitable beam profile enables the integration of functional photonic elements, e.g., Bragg gratings, into the waveguide. Thus, it also enables the generation of integrated photonic sensors. In addition, internal fs laser-induced modifications are characterized by a lower thermal stability as compared to the pristine polymer material. By performing a post-annealing process step, internal hollow microstructures are created by gaseous degradation of the exposed areas. Circular microchannels can be generated in a deliberately chosen layout by employing motorized 3D stages. In comparison to etching-based fabrication methods the proposed technology facilitates unlimited channel lengths, as it omits restrictions arising from an etching selectivity and duration. Altogether, this contribution paves the way towards the fabrication of internal three-dimensional optofluidic devices, equipped with a photonic sensor. In contrast, microfluidic and photonic structures are both created by femtosecond laser direct writing inside of transparent polymers. KW - Femtosekundenlaser Y1 - 2021 U6 - https://doi.org/10.2961/jlmn.2021.01.2009 VL - 16 IS - 1 SP - 1 EP - 6 ER - TY - CHAP A1 - Laun, Ute A1 - Hummel, Katrin A1 - Rötzel, Peter T1 - The interdisciplinary nature of sustainability accounting – a systematic literature review and a network citation study T2 - Virtual Annual Congress of the European Accounting Association N2 - Sustainability accounting as a distinct discipline has evolved over the last decades and is still expanding. As a multidimensional concept, sustainability accounting, however, relates to various other disciplines and thus provides a suitable setting to examine the extent of interdisciplinarity in accounting research. This paper investigates sustainability accounting in in twofold way. First, it provides a comprehensive and systematic review of academic literature addressing sustainability accounting topics. Based on a systematic search strategy capturing articles in the fields of finance and accounting, management, economics, organization and behavioral research, and international business, we determine a sample of 5,245 articles. Descriptive findings show that equally large proportions of the sample articles are published in accounting, management, and organization journals. Using citation network analysis, we identify existing research clusters within this sample and analyse them with respect to their delineations and interactions. Our results reveal that cluster formation relates to specific subject areas with some clusters showing limited interactions to other subject areas, while other clusters are more “interdisciplinary”. Interviews with influential researchers from the most prominent clusters in the network complement the network analysis results, providing insights into the establishment of paradigms and patterns in academic research that lead to the failure of knowledge integration and impede the transfer of research insights into business and politics. KW - Accounting KW - Sustainability KW - Corporate social responsibility (CSR) KW - Systematic literature review KW - Citation network analysis KW - Rechnungswesen KW - Rechnungslegung Y1 - 2021 UR - https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3641722 VL - 2020 ER - TY - RPRT A1 - Vogl, Markus A1 - Rötzel, Peter T1 - Insights, Trends and Frontiers: A Literature Review on Financial and Risk Modelling in the Information Age (2008-2019) N2 - This study provides an overview of the model evolution and research trends in the field of financial and risk modelling by applying a bibliometric approach from 2008–2019 and an overall citation network analysis. We present a content analysis of contributing authors, countries, journals, main topics, agreements, disagreements and frontiers within the research community and highlight quantitative features such as implemented models, aggregated model-family combinations and algorithms. Moreover, we describe the data sets employed by researchers. Finally, we discuss insights, such as the main statement, namely the non-existence of a “single-best”-approach as well as the future prospects of our findings. KW - Financial Modelling KW - Literature Review KW - risk modelling KW - Quantitative Finance KW - Citation Network KW - Risikomanagment KW - Finanzwirtschaft KW - Modellierung Y1 - 2021 UR - https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3764570 ER - TY - CHAP A1 - Rötzel, Peter A1 - Weber, Maximilian T1 - Bridging organizational resilience and management control systems - a systematic review T2 - Annual Conference of the European Accounting Association N2 - Organizations have repeatedly faced challenges due to (natural) disasters such as pandemics, economic or financial crises, and unexpected events. One reason why some firms cope more efficiently with such unexpected events than others has long been the subject of research, might be found in their resilience design. However, there is still no consensus in the literature and there is no common understanding of the definitions, the conceptualizations of resilience at the organizational level, and the interaction with management control systems (MCS). This study bridges MCS and resilience literature and provides a broader understanding of the relationship between the organization and adversity. Due to its ability to successfully control an organization and provide an effective control environment, we use Simons’ levers of control framework (LOC) as framework for integrating organizational resilience into MCS. We perform a systematic reviewing of analytical conceptualizations and definitions of management control systems (levers of control) and organizational resilience, supplemented by current empirical findings. Based on literature, we provide a framework which integrates organizational resilience into management control systems. Our findings show that the integration of resilience aspects into MCS enables firms to manage resilience at the organizational level. KW - Organizational resilience KW - Management control systems KW - Levers of Control KW - Systematic Review KW - Resilience KW - Management KW - Kontrollsystem Y1 - 2021 ER - TY - CHAP A1 - Rötzel, Peter A1 - Smeets, Mario A1 - Osterndorf, Ralf T1 - RPA for the Financial Industry Particular challenges and outstanding suitability combined T2 - Robotic Process Automation N2 - Like many service industries, the financial industry is largely characterized by administrative and back-office processes and distinguished by a broad systems landscape with a high proportion of legacy systems. Missing interfaces between Information Systems, User Interfaces or Web Applica-tions often require many manual activities. As banks are often functionally organized into traditional departments, a process-oriented organizational structure is rarely in place. The financial industry therefore offers enormous potential for the use of Robotic Process Automation (RPA) and the rais-ing of potential benefits such as process-related cost savings, time reductions and quality im-provements. The aim of this chapter is to describe the tremendous opportunities that the use of RPA technology offers to the financial industry and to explain how these opportunities can be realized. Therefore, we start by explaining the challenges that progressive digitalization poses to the industry and how RPA, but also more advanced technologies (that work not only rule-based but also define own rules), such as Artificial Intelligence (AI), can help to overcome them. As well as providing an over-view of the various applications of RPA in the financial industry, we also provide a comprehensive case study of a relevant practical application. KW - Robot Process Automation KW - Artificial Intelligence KW - Finance KW - Accouting KW - Legacy systems KW - Finanzdienstleistungsinstitut KW - Automation KW - Digitalisierung Y1 - 2021 PB - De Gruyter CY - Amsterdam ER -