@article{PremSindersbergerStriegletal., author = {Prem, Nina and Sindersberger, Dirk and Striegl, Birgit and B{\"o}hm, Valter and Monkman, Gareth J.}, title = {Shape memory effects using magnetoactive Boron-organo-silicon oxide polymers}, series = {Macromolecular Chemistry and Physics}, volume = {221}, journal = {Macromolecular Chemistry and Physics}, number = {15}, publisher = {Wiley}, doi = {10.1002/macp.202000149}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-23205}, pages = {1 -- 8}, abstract = {Thermomechanical shape memory materials have certain disadvantages when it comes to 3D volumetric reproduction intended for rapid prototyping or robotic prehension. The need to constantly supply energy to counteract elastic retraction forces in order to maintain the required geometry, together with the inability to achieve conformal stability at elevated temperatures, limits the application of thermal shape memory polymers. Form removal also presents problems as most viscoelastic materials do not ensure demolding stability. This work demonstrates how magnetoactive boron-organo-silicon oxide polymers under the influence of an applied magnetic field can be used to achieve energy free sustainable volumetric shape memory effects over extended periods. The rheopectic properties of boron-organo-silicon oxide materials sustain form removal without mold distortion.}, language = {en} } @article{PangerlSukulRuecketal., author = {Pangerl, Jonas and Sukul, Pritam and R{\"u}ck, Thomas and Fuchs, Patricia and Weigl, Stefan and Miekisch, Wolfram and Bierl, Rudolf and Matysik, Frank-Michael}, title = {An inexpensive UV-LED photoacoustic based real-time sensor-system detecting exhaled trace-acetone}, series = {Photoacoustics}, volume = {38}, journal = {Photoacoustics}, publisher = {Elsevier}, issn = {2213-5979}, doi = {10.1016/j.pacs.2024.100604}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-71279}, pages = {12}, abstract = {n this research we present a low-cost system for breath acetone analysis based on UV-LED photoacoustic spectroscopy. We considered the end-tidal phase of exhalation, which represents the systemic concentrations of volatile organic compounds (VOCs) - providing clinically relevant information about the human health. This is achieved via the development of a CO2-triggered breath sampling system, which collected alveolar breath over several minutes in sterile and inert containers. A real-time mass spectrometer is coupled to serve as a reference device for calibration measurements and subsequent breath analysis. The new sensor system provided a 3σ detection limit of 8.3 ppbV and an NNEA of 1.4E-9 Wcm 1Hz 0.5. In terms of the performed breath analysis measurements, 12 out of 13 fell within the error margin of the photoacoustic measurement system, demonstrating the reliability of the measurements in the field.}, language = {en} } @article{MaierSchlattlGuessetal., author = {Maier, Robert and Schlattl, Andreas and Guess, Thomas and Mottok, J{\"u}rgen}, title = {CausalOps - Towards an industrial lifecycle for causal probabilistic graphical models}, series = {Information and Software Technology}, journal = {Information and Software Technology}, publisher = {Elsevier}, issn = {0950-5849}, doi = {10.1016/j.infsof.2024.107520}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-73350}, abstract = {Context: Causal probabilistic graph-based models have gained widespread utility, enabling the modeling of cause-and-effect relationships across diverse domains. With their rising adoption in new areas, such as safety analysis of complex systems, software engineering, and machine learning, the need for an integrated lifecycle framework akin to DevOps and MLOps has emerged. Currently, such a reference for organizations interested in employing causal engineering is missing. This lack of guidance hinders the incorporation and maturation of causal methods in the context of real-life applications. Objective: This work contextualizes causal model usage across different stages and stakeholders and outlines a holistic view of creating and maintaining them within the process landscape of an organization. Method: A novel lifecycle framework for causal model development and application called CausalOps is proposed. By defining key entities, dependencies, and intermediate artifacts generated during causal engineering, a consistent vocabulary and workflow model to guide organizations in adopting causal methods are established. Results: Based on the early adoption of the discussed methodology to a real-life problem within the automotive domain, an experience report underlining the practicability and challenges of the proposed approach is discussed. Conclusion: It is concluded that besides current technical advancements in various aspects of causal engineering, an overarching lifecycle framework that integrates these methods into organizational practices is missing. Although diverse skills from adjacent disciplines are widely available, guidance on how to transfer these assets into causality-driven practices still need to be addressed in the published literature. CausalOps' aim is to set a baseline for the adoption of causal methods in practical applications within interested organizations and the causality community.}, language = {en} } @article{HaugAltenbuchnerWeber, author = {Haug, Sonja and Altenbuchner, Amelie and Weber, Karsten}, title = {Elektronische Patientenakte und Freigabe von Gesundheitsdaten}, series = {P{\"a}diatrie \& P{\"a}dologie}, journal = {P{\"a}diatrie \& P{\"a}dologie}, publisher = {Springer}, issn = {0030-9338}, doi = {10.1007/s00608-024-01237-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-73847}, abstract = {Hintergrund In Deutschland wird die elektronische Patientenakte (ePA) eingef{\"u}hrt. Fragestellung Untersucht werden Nutzungsbereitschaft der ePA, Einstellung zu Gesundheitsdaten und Daten{\"u}bermittlung bei Personen mit und ohne Kinder. Methoden Telefonbefragung bei einer Zufallsstichprobe der Bev{\"o}lkerung in Deutschland (2022, n = 1308). Ergebnisse Die ePA ist bei Haushalten mit Kindern mehrheitlich unbekannt. Ihre Nutzungsbereitschaft der ePA und die Zustimmung zur Speicherung von Gesundheitsdaten ist geringer, aber sie sind h{\"a}ufiger als Haushalte ohne Kinder bereit zur Freigabe ihrer Gesundheitsdaten f{\"u}r die Forschung. Schlussfolgerung Es besteht Aufkl{\"a}rungsbedarf {\"u}ber die Speicherung von Gesundheitsdaten. Gew{\"u}nscht wird zunehmend eine digitale Arzt-Patienten-Kommunikation.}, language = {de} } @article{BauerSterner, author = {Bauer, Franz and Sterner, Michael}, title = {Impacts of lifestyle changes on energy demand and greenhouse gas emissions in Germany}, series = {Renewable and Sustainable Energy Reviews}, volume = {207}, journal = {Renewable and Sustainable Energy Reviews}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1364-0321}, doi = {10.1016/j.rser.2024.114944}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-77682}, pages = {17}, abstract = {Most energy scenario studies typically focus on technological options and fuel substitution for decarbonising future energy systems. Lifestyle changes are rarely considered, although they can significantly reduce energy demand and climate change mitigation efforts. By using an energy system model, this study shows that it is possible to reduce final energy demand in Germany by 61 \% in 2050 relative to 2019 levels, resulting in an annual per capita energy demand of 44 GJ for a representative country of the Global North. This goal can be achieved through a combination of technological measures and lifestyle changes without sacrificing a decent standard of living. Societal chances can eliminate reliance on not-yet-established negative emission technologies, reduce energy dependency, and reduce the need for energy-intensive hydrogen and e-fuels. Downsizing the energy system provides an opportunity for strengthening climate change mitigation, decrease material demand and reduce land use.}, language = {en} } @article{AlbrechtHellerbrandWeiningeretal., author = {Albrecht, Sophie Viktoria and Hellerbrand, Stefan and Weininger, Florian and Thiel, Charlotte}, title = {Strategies for Minimizing Environmental Impact in Construction: A Case Study of a Cementitious 3D Printed Lost Formwork for a Staircase}, series = {materials}, volume = {18}, journal = {materials}, publisher = {MDPI}, doi = {10.3390/ma18040825}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-79236}, pages = {18}, abstract = {The construction industry faces significant challenges, including environmental sustainability, rising material costs, and a shortage of skilled labor. Digital fabrication technologies offer innovative solutions to address these issues by reducing raw material consumption and waste generation. Among these, 3D printing technologies offer distinct advantages over traditional construction methods, particularly in handling complex geometries. However, the significant environmental impact of cement in 3D printed concrete, due to its high rheological and printability requirements, remains a concern. This study introduces a novel application of 3D printed permanent formwork in the construction of a winder staircase, assessed through an Environmental Life Cycle Assessment (LCA) from cradle to gate. By comparing the environmental impacts of various construction materials and processes, this study highlights the comparative advantages and disadvantages of conventional methods versus 3D printing. The LCA results reveal that traditional production methods, particularly those using plywood formwork, exhibit higher environmental impacts. In contrast, timber formwork performs better than most 3D printed mixtures in terms of Global Warming Potential (GWP), Acidification Potential (AP), and abiotic depletion potential (ADP). The findings of this study underscore the potential of additive manufacturing for sustainable construction, particularly through the use of low-clinker cement in 3D printed formwork, offering a promising pathway towards reducing the environmental footprint of construction activities}, language = {en} } @article{EscherRueckJobstetal., author = {Escher, Lukas and R{\"u}ck, Thomas and Jobst, Simon and Pangerl, Jonas and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Photodissociation-Driven Photoacoustic Spectroscopy with UV-LEDs for Ozone Detection}, series = {Photoacoustics}, volume = {43}, journal = {Photoacoustics}, publisher = {Elsevier BV}, issn = {2213-5979}, doi = {10.1016/j.pacs.2025.100718}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-80076}, pages = {16}, abstract = {This study presents the development and evaluation of a UV-LED based photoacoustic (PA) measurement system for ozone (O3) detection to demonstrate its potential for low-cost and accurate sensing while for the first time addressing the importance of photodissociation for PA signal generation for O3 in the UV range. With a detection limit of 7.9 ppbV, the system exhibits a significant advancement over state-of-the-art UV-PA O3 detection and is on par with laser-based setups. Following a novel discussion of the PA signal arising from photodissociation and its products, cross-sensitivity effects due to environmental factors such as temperature and gas composition were systematically analyzed. A digital twin driven compensation for these influences was implemented and evaluated. Despite the challenges associated with modeling the effects of H2O and CO2, the PA system shows considerable potential, though further studies in real world applications must be conducted.}, language = {en} } @article{WestnerReichenederMatschi, author = {Westner, Markus and Reicheneder, Matthias and Matschi, Markus}, title = {From Captive Centers to Global Integration}, series = {Information Resources Management Journal}, volume = {38}, journal = {Information Resources Management Journal}, number = {1}, publisher = {IGI Global}, issn = {1533-7979}, doi = {10.4018/IRMJ.373322}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-80406}, pages = {25}, abstract = {Contemporary developments in virtual work and global talent management are transforming information technology (IT) nearshoring and offshoring practices, yet research on organizational responses remains limited. Through expert interviews with 33 IT executives (76\% chief information officers) from Germany's top 500 companies, this article examines organizational models, strategies, and good practices in IT nearshoring and offshoring. It reveals a shift from traditional captive centers toward fully integrated global teams, enabling high-value task delivery and reflecting increased workforce maturity. Companies are expanding their operations driven by talent needs rather than cost savings, with success factors including employee integration and robust on-site management. This study contributes to theory and practice by providing a framework for understanding organizational models in global IT delivery and offering actionable insights for executives, emphasizing workforce integration over geographical separation.}, subject = {Offshoring}, language = {en} } @article{HauslerHolznerEhrnspergeretal., author = {Hausler, Peter and Holzner, Lukas and Ehrnsperger, Matthias and Bierl, Rudolf}, title = {Evaluation of the creep strength of samples produced by fused deposition modeling}, series = {Open Engineering}, volume = {14}, journal = {Open Engineering}, number = {1}, publisher = {de Gruyter}, doi = {10.1515/eng-2024-0084}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-79760}, pages = {10}, abstract = {Data sheets for 3D printing materials typically include softening temperature, impact strength, tensile strength, and stiffness. However, creep strength, an important parameter for components used over an extended period, is usually not included. Nevertheless, this parameter is of significant importance for components that are used over an extended period of time.This study compares the long-term creep behavior of a selection of materials that are commonly used in fused deposition modeling 3D printing. The materials under investigation are acrylonitrile butadiene styrene, acrylonitrile styrene acrylate, polylactic acid, and polycarbonate. In addition, the influence of fiber reinforcements on these materials is also examined. A simple, reproducible test procedure is proposed for users to determine and compare creep resistance of materials. This enables developers to select materials suitable for their own requirements on creep resistance and allows 3D-printing users to compare different materials. Results suggest that fiber reinforcement generally improves creep stability in 3D-printing materials, with GreenTEC Pro Carbon and add:north PC Blend HT LCF showing the most promise in this study.}, language = {en} } @article{KastenmeierSieglEhrlichetal., author = {Kastenmeier, Andreas and Siegl, Marco and Ehrlich, Ingo and Gebbeken, Norbert}, title = {Review of elasto-static models for three-dimensional analysis of thick-walled anisotropic tubes}, series = {Journal of Composite Materials}, journal = {Journal of Composite Materials}, publisher = {Sage}, doi = {10.1177/00219983231215863}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-67521}, abstract = {Most shell or beam models of anisotropic tubes under bending have no validity for thick-walled structures. As a result, the need to develop three-dimensional formulations which allow a change in the stress, strain and displacement distributions across the radial component arises. Basic formulations on three-dimensional anisotropic elasticity were made either stressor displacement-based by Lekhnitskii or Stroh on plates. Lekhnitskii also was the first to expand these analytical formulations to tubes under various loading conditions. This paper presents a review of the stress and strain analysis of tube models using three-dimensional anisotropic elasticity. The focus lies on layered structures, like fiber-reinforced plastics, under various bending loads, although the basic formulations and models regarding axisymmetric loads are briefly discussed. One section is also dedicated to the determination of an equivalent bending stiffness of tubes.}, language = {en} } @article{HaugSchnellRaptisetal., author = {Haug, Sonja and Schnell, Rainer and Raptis, Georgios and Dotter, Caroline and Weber, Karsten}, title = {Wissen und Einstellung zur Speicherung und Nutzung von Gesundheitsdaten: Ergebnisse einer Bev{\"o}lkerungsbefragung}, series = {Zeitschrift f{\"u}r Evidenz, Fortbildung und Qualit{\"a}t im Gesundheitswesen}, journal = {Zeitschrift f{\"u}r Evidenz, Fortbildung und Qualit{\"a}t im Gesundheitswesen}, publisher = {Elsevier}, issn = {1865-9217}, doi = {10.1016/j.zefq.2023.11.001}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-67461}, pages = {50 -- 58}, abstract = {Hintergrund/Zielsetzung Der Beitrag befasst sich mit dem Wissenstand und der Einstellung der Bev{\"o}lkerung. Betrachtet werden die {\"U}bermittlung und Verf{\"u}gbarkeit von Gesundheitsdaten, Gesundheitsregister, die elektronische Patientenakte, Einwilligungsverfahren f{\"u}r die {\"U}bermittlung von Daten und der Zugriff auf Gesundheitsdaten zu Forschungszwecken. Methoden Die Studie basiert auf einer computergest{\"u}tzten Telefonbefragung (Dual-Frame) bei einer Zufallsstichprobe der Bev{\"o}lkerung in Deutschland im Zeitraum 01.-27.06.2022 (n = 1.308). Ergebnisse Der Wissensstand zur {\"U}bermittlung von Gesundheitsdaten an Krankenkassen ist hoch, wohingegen das Vorhandensein zentraler Sterbe-, Impf- und Gesundheitsregister sowie der Zugriff auf Gesundheitsdaten durch behandelnde {\"A}rztinnen und {\"A}rzte {\"u}bersch{\"a}tzt werden. Die Akzeptanz medizinischer Register ist sehr hoch. Die elektronische Patientenakte ist bei der H{\"a}lfte der Bev{\"o}lkerung unbekannt, die Nutzungsbereitschaft ist eher gering ausgepr{\"a}gt; bei der {\"U}bertragung von Daten wird eine Zustimmungsoption bevorzugt, und {\"u}ber achtzig Prozent w{\"u}rden die Daten der elektronischen Patientenakte zur Forschung freigeben. Drei Viertel w{\"u}rden ihre Gesundheitsdaten allgemein zur Forschung freigeben, insbesondere an Universit{\"a}ten in Deutschland, wobei meist Anonymit{\"a}t Bedingung ist. Die Bereitschaft zur Datenfreigabe steigt mit der H{\"o}he des Vertrauens in die Presse sowie in Universit{\"a}ten und Hochschulen, und sie sinkt, wenn ein Datenleck als schwerwiegend erachtet wird. Diskussion und Schlussfolgerung In Deutschland besteht, wie in anderen europ{\"a}ischen L{\"a}ndern, eine große Bereitschaft zur Freigabe von Gesundheitsdaten zu Forschungszwecken. Dagegen ist der Wunsch zur Nutzung der elektronischen Patientenakte eher gering. Ebenso niedrig ist die Akzeptanz einer Widerspruchsoption, die jedoch als Voraussetzung f{\"u}r eine erfolgreiche Einf{\"u}hrung einer elektronischen Patientenakte gilt. Vertrauen in die Forschung und staatliche Stellen, die Gesundheitsdaten verarbeiten, sind zentrale Faktoren.}, language = {en} } @article{ScharfHaugRitthaleretal., author = {Scharf, Anna and Haug, Sonja and Ritthaler, Markus and Raptis, Georgios}, title = {Chancen und Herausforderungen der Digitalisierung bei der Rehabilitation - Ergebnisse einer Befragung von Rehabilitationseinrichtungen}, series = {Die Rehabilitation: Zeitschrift f{\"u}r Praxis und Forschung in der Rehabilitation}, volume = {62}, journal = {Die Rehabilitation: Zeitschrift f{\"u}r Praxis und Forschung in der Rehabilitation}, number = {5}, publisher = {Thieme}, address = {Stuttgart}, doi = {10.1055/a-2123-1566}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-64726}, pages = {299 -- 307}, abstract = {Ziel der Studie: Ziel der Studie ist die Messung des Stands der Digitalisierung und die mit einer Anbindung an die Telematikinfrastruktur verbundenen Chancen und Herausforderungen f{\"u}r Rehabilitationseinrichtungen. Methodik: Teilstandardisierte Online-Befragung bei Tr{\"a}gern von Rehabilitationseinrichtungen in Bayern (n=33). Der Fragebogen mit 36 Fragen beinhaltet eine leicht ver{\"a}nderte Skala auf Basis des „Electronic Medical Record Adoption Model (EMRAM)". Ergebnisse: Der Digitalisierungsgrad wurde in 70 Prozent der Rehabilitationseinrichtungen mit Stufe 0 angegeben (Stufenmodell bis 7). Die {\"U}bermittlung patientenbezogener Daten (Eingang und Ausgang) erfolgt h{\"a}ufig analog, wohingegen die Verarbeitung innerhalb der Einrichtung in vielen F{\"a}llen bereits {\"u}berwiegend digital ist. Beim Anschluss an die Telematikinfrastruktur wird hoher Aufwand bei der Installation, aber auch der Schulung des Personals und der Anpassung der Arbeitsorganisation gesehen. Schlussfolgerung: Durch {\"A}nderung der gesetzlich-finanziellen Lage in Deutschland er{\"o}ffnen sich f{\"u}r Rehabilitationseinrichtungen neue M{\"o}glichkeiten einer verst{\"a}rkten Digitalisierung. H{\"u}rden h{\"a}ngen mit Anforderungen an IT-Sicherheit, Schulung des Personals und sowie dem ebenfalls geringen Digitalisierungsstand bei Krankenh{\"a}usern und {\"A}rzt*innen sowie Patient*innen zusammen, die eine digitale Daten{\"u}bermittlung erschweren.}, language = {de} } @article{Richter, author = {Richter, Stefanie}, title = {Erleben von Zukunftsunsicherheit, Armutsrisiken und prek{\"a}ren Lebenslagen im Pflegeheim}, series = {Zeitschrift f{\"u}r Gerontologie und Geriatrie}, journal = {Zeitschrift f{\"u}r Gerontologie und Geriatrie}, edition = {Online first}, publisher = {Springer}, doi = {10.1007/s00391-023-02231-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-64350}, pages = {1 -- 6}, abstract = {Die Situation von Menschen im Pflegeheim, die besonders dem Risiko der „pflegebedingten Verarmung" ausgesetzt sind, ist in der Forschung wenig pr{\"a}sent. Der Beitrag befasst sich mit dem Erleben von Unsicherheiten, Armut und prek{\"a}ren Lebenslagen {\"a}lterer Menschen im Heim. Grundlage liefern Daten einer ethnographischen Studie zum {\"A}lterwerden und zum Leben mit chronischen Erkrankungen. Anhand von F{\"a}llen wird ein Spektrum prek{\"a}rer Lebenslagen skizziert. Deutlich wird u. a.: Menschen mit diversen soziobiografischen Hintergr{\"u}nden k{\"o}nnen im Zuge von Hilfebed{\"u}rftigkeit und Heim{\"u}berg{\"a}ngen von Unsicherheiten, Armut und prek{\"a}ren Lebenslagen betroffen sein. Nicht zu wissen, ob das verf{\"u}gbare Geld gen{\"u}gt, um Kostensteigerungen bis zum Lebensende zu decken, kennzeichnet eine h{\"a}ufig erlebte Zukunftsunsicherheit; drohende Armut bzw. die Abh{\"a}ngigkeit von Sozialhilfe k{\"o}nnen pflege- und institutionell bedingte Verlusterfahrungen von Autonomie, Teilhabe und Lebensgestaltung versch{\"a}rfen und den Gesamtzustand weiter destabilisieren. Das Erleiden bleibt weitgehend unsichtbar; strukturelle Probleme werden individualisiert.}, language = {de} } @article{Goertler, author = {G{\"o}rtler, Michael}, title = {Bildung und Zeit im Kontext der Sozialen Arbeit : Theoretische {\"U}berlegungen zur Bedeutung von Zeit f{\"u}r Bildungsprozesse im Kontext der Sozialen Arbeit}, series = {Sozial Extra}, volume = {47}, journal = {Sozial Extra}, number = {1}, publisher = {Springer}, doi = {10.1007/s12054-023-00570-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-60988}, pages = {46 -- 49}, abstract = {Die Bedeutung von Zeit f{\"u}r Bildungsprozesse im Kontext der Sozialen Arbeit ist bisher wenig erforscht. Um sich dieser Fragestellung anzun{\"a}hern, werden in diesem Beitrag theoretische {\"U}berlegungen im Anschluss an Diskurse zu Bildung und Zeit in der P{\"a}dagogik angestellt. Dabei wird Zeit als erm{\"o}glichender, {\"o}konomischer und politischer Faktor diskutiert, um die Perspektive der Sozialen Arbeit auf Bildungsprozesse zu erweitern.}, language = {de} } @article{PongratzTixWolfrumetal., author = {Pongratz, Christian and Tix, Janek and Wolfrum, Johannes and Gerke, Steffen and Ehrlich, Ingo and Br{\"u}nig, Michael}, title = {Test Setup for Investigating the Impact Behavior of Biaxially Prestressed Composite Laminates}, series = {Experimental Techniques}, journal = {Experimental Techniques}, publisher = {Springer Nature}, issn = {0732-8818}, doi = {10.1007/s40799-024-00701-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-70355}, pages = {14 S.}, abstract = {Instrumented impact testing and compression-after-impact testing are important to adequately qualify material behavior and safely design composite structures. However, the stresses to which fiber-reinforced plastic components are typically subjected in practice are not considered in the impact test methods recommended in guidelines or standards. In this paper, a test setup for investigating the impact behavior of composite specimens under plane uniaxial and biaxial preloading is presented. For this purpose, a special test setup consisting of a biaxial testing machine and a specially designed drop-weight tower was developed. The design decisions were derived from existing guidelines and standards with the aim of inducing barely visible impact damage in laminated carbon fiber-reinforced plastic specimens. Several measurement systems have been integrated into the setup to allow comprehensive observation of the impact event and specimen behavior. A feasibility test was performed with biaxially prestressed carbon fiber-reinforced plastic specimens in comparison with unstressed reference tests. The compressive-tensile prestressing resulted in lower maximum contact forces, higher maximum deflections, higher residual deflections and a different damage pattern, which was investigated by light microscopic analysis. Finally, the functionality of the experimental setup is discussed, and the results seem to indicate that the test setup and parameters were properly chosen to investigate the effect of prestresses on the impacts behavior of composite structures, in particular for barely visible subsequent damages.}, subject = {Faserverbundwerkstoff}, language = {en} } @article{GradZentgrafSchultheissetal., author = {Grad, Marius and Zentgraf, Jan and Schultheiss, Ulrich and Esper, Lukas and Diemar, Andreas and Noster, Ulf and Spiess, Lothar}, title = {Effect of Carbon Content on the Phase Composition, Microstructure and Mechanical Properties of the TiC Layer Formed in Hot-Pressed Titanium-Steel Composites}, series = {Metals}, volume = {14}, journal = {Metals}, number = {9}, publisher = {MDPI AG}, issn = {2075-4701}, doi = {10.3390/met14090959}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-74617}, abstract = {During the hot pressing of pure titanium and different carbon steels in a temperature range of ϑ = 950-1050 °C, a compound layer up to dL≈10 μm thick is formed at the titanium-steel interface. With a higher carbon content of the used steel, the layer thickness increases. The carbon concentration within the layer is in the range of stoichiometry for TiC. Apart from TiC, no other phases can be detected by X-ray diffraction (XRD) measurements inside the formed layer. The calculation of the activation energy for the TiC layer formation is Q = 126.5-136.7 kJ mol-1 and is independent of the carbon content of the steel. The resulting microstructure has a grain size gradient, wherein the mechanical properties, such as hardness and Young's modulus, are almost constant. Statistical analysis using Response Surface Methodology (RSM) indicates that the carbon content of the steel has the most significant influence on layer thickness, followed by annealing temperature and annealing time. By selecting the appropriate carbon steel and the subsequent removal of the steel, it is possible to produce targeted TiC layers on titanium substrates, which holds enormous potential for this material in wear-intensive applications.}, language = {en} } @article{AuerSchieblIversenetal., author = {Auer, Simon and Schiebl, Jonas and Iversen, Kristoffer and Subhash Chander, Divyaksh and Damsgaard, Michael and Dendorfer, Sebastian}, title = {Biomechanical assessment of the design and efficiency of occupational exoskeletons with the AnyBody Modeling System}, series = {Zeitschrift f{\"u}r Arbeitswissenschaften}, volume = {76}, journal = {Zeitschrift f{\"u}r Arbeitswissenschaften}, number = {4}, publisher = {Springer Nature}, doi = {10.1007/s41449-022-00336-4}, pages = {440 -- 449}, abstract = {Exoskeletons were invented over 100 years ago but have only become popular in the last two decades, especially in the working industry as they can decrease work-related loads significantly. The most often used exoskeletons are for the lower back and shoulder since these are commonly affected body regions. All devices have in common that their purpose is to reduce internal loads of vulnerable body regions. Nevertheless, there is still little understanding on how biomechanical loading in the human body changes when exoskeletons are used. Therefore, further analyses are needed. A promising candidate for these are musculoskeletal models, which are based on an inverse dynamics approach and can calculate external parameters such as ground reaction forces or other interaction forces as well as internal parameters such as joint reaction forces or muscle activities. The various examples in the literature show that these models are increasingly used for assessing the biomechanical effects of exoskeletons on the human body. Furthermore, musculoskeletal models can calculate biomechanical loadings of humans with and without exoskeletons for all kinds of applications and allow an evaluation of their purpose. Practical Relevance: This article highlights the possibilities of musculoskeletal models for assessing the design and efficiency of occupational exoskeletons. Several practical use cases are described along with distinct descriptions of common implications of musculoskeletal and exoskeleton modeling.}, language = {en} } @article{MelznerPfeifferSuessetal., author = {Melzner, Maximilian and Pfeiffer, Christian and Suess, Franz and Dendorfer, Sebastian}, title = {Musculoskeletal simulation of elbow stability for common injury patterns}, series = {Journal of Orthopaedic Research}, volume = {41}, journal = {Journal of Orthopaedic Research}, number = {6}, publisher = {Wiley}, issn = {1554-527X}, doi = {10.1002/jor.25460}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-54819}, pages = {1356 -- 1364}, abstract = {Elbow stability is derived from a combination of muscular, ligamentous, and bony structures. After an elbow trauma the stability of the joint is an important decision criterion for the subsequent treatment. The decision regarding non-operative/operative care depends mostly on subjective assessments of medical experts. Therefore, the aim of this study is to use musculoskeletal simulations as an objective assessment tool to investigate the extent to which failure of different stabilizers affects the elbow stability and how these observations correspond to the assessment from clinical practice. A musculoskeletal elbow simulation model was developed for this aim. To investigate the stability of the elbow, varus/valgus moments were applied under 0°, 45°and 90° flexion while the respective cubital angle was analyzed. This was performed for nine different injury scenarios, which were also evaluated for stability by clinical experts. With the results, it can be determined by which injury pattern and under which flexion angle the elbow stability is impaired regarding varus/valgus moments. The scenario with a complete failure of the medial and lateral ligaments and a fracture of the radial head was identified as having the greatest instability. The study presented a numerical determination of elbow stability against varus/valgus moments regarding clinical injury patterns, as well as a comparison of the numerical outcome with experience gained in clinical practice. The numerical predictions agree well with the assessments of the clinical specialists. Thus, the results from musculoskeletal simulation can make an important contribution to a more objective assessment of the elbow stability.}, language = {en} } @article{ReinkerBlaesingBierletal., author = {Reinker, Lukas and Bl{\"a}sing, Dominic and Bierl, Rudolf and Ulbricht, Sabina and Dendorfer, Sebastian}, title = {Correlation of Acceleration Curves in Gravitational Direction for Different Body Segments during High-Impact Jumping Exercises}, series = {sensors}, volume = {23}, journal = {sensors}, number = {4}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/s23042276}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-58217}, abstract = {Osteoporosis is a common disease of old age. However, in many cases, it can be very well prevented and counteracted with physical activity, especially high-impact exercises. Wearables have the potential to provide data that can help with continuous monitoring of patients during therapy phases or preventive exercise programs in everyday life. This study aimed to determine the accuracy and reliability of measured acceleration data at different body positions compared to accelerations at the pelvis during different jumping exercises. Accelerations at the hips have been investigated in previous studies with regard to osteoporosis prevention. Data were collected using an IMU-based motion capture system (Xsens) consisting of 17 sensors. Forty-nine subjects were included in this study. The analysis shows the correlation between impacts and the corresponding drop height, which are dependent on the respective exercise. Very high correlations (0.83-0.94) were found between accelerations at the pelvis and the other measured segments at the upper body. The foot sensors provided very weak correlations (0.20-0.27). Accelerations measured at the pelvis during jumping exercises can be tracked very well on the upper body and upper extremities, including locations where smart devices are typically worn, which gives possibilities for remote and continuous monitoring of programs.}, language = {en} } @article{AuerKubowitschDendorfer, author = {Auer, Simon and Kubowitsch, Simone and Dendorfer, Sebastian}, title = {Kombinierter Einfluss von psychologischen und biomechanischen Faktoren auf die muskul{\"a}ren Belastungen beim Fußballspielen}, series = {Die Orthop{\"a}die}, volume = {52}, journal = {Die Orthop{\"a}die}, number = {11}, publisher = {Springer}, doi = {10.1007/s00132-023-04437-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-65113}, pages = {1 -- 6}, abstract = {When mental stress and musculoskeletal loading interact, the risk for injury increases due to altered body kinematics and increased muscle tension. These changes can be detected with musculoskeletal models, and mental loading and stress must be analyzed at emotional, cognitive, and behavioral levels. To investigate these kinematic and loading changes under stress, competitive athletes were subjected to mental stress during highly dynamic movements, and musculoskeletal models were used to analyze the biomechanical loading. It was shown that under mental stress, independent of the subjective perception, a strong change in muscle forces can occur. Accordingly, competitive athletes should undergo screenings to assess individual movement patterns and promote general stress resilience.}, language = {de} } @article{KoeckStrieglKrausetal., author = {K{\"o}ck, Hannah and Striegl, Birgit and Kraus, Annalena and Zborilova, Magdalena and Christiansen, Silke H. and Sch{\"a}fer, Nicole and Gr{\"a}ssel, Susanne and Hornberger, Helga}, title = {In Vitro Analysis of Human Cartilage Infiltrated by Hydrogels and Hydrogel-Encapsulated Chondrocytes}, series = {Bioengineering}, volume = {10}, journal = {Bioengineering}, publisher = {MDPI}, doi = {10.3390/bioengineering10070767}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-61235}, pages = {1 -- 21}, abstract = {Osteoarthritis (OA) is a degenerative joint disease causing loss of articular cartilage and structural damage in all joint tissues. Given the limited regenerative capacity of articular cartilage, methods to support the native structural properties of articular cartilage are highly anticipated. The aim of this study was to infiltrate zwitterionic monomer solutions into human OA-cartilage explants to replace lost proteoglycans. The study included polymerization and deposition of methacryloyloxyethyl-phosphorylcholine- and a novel sulfobetaine-methacrylate-based monomer solution within ex vivo human OA-cartilage explants and the encapsulation of isolated chondrocytes within hydrogels and the corresponding effects on chondrocyte viability. The results demonstrated that zwitterionic cartilage-hydrogel networks are formed by infiltration. In general, cytotoxic effects of the monomer solutions were observed, as was a time-dependent infiltration behavior into the tissue accompanied by increasing cell death and penetration depth. The successful deposition of zwitterionic hydrogels within OA cartilage identifies the infiltration method as a potential future therapeutic option for the repair/replacement of OA-cartilage extracellular suprastructure. Due to the toxic effects of the monomer solutions, the focus should be on sealing the OA-cartilage surface, instead of complete infiltration. An alternative treatment option for focal cartilage defects could be the usage of monomer solutions, especially the novel generated sulfobetaine-methacrylate-based monomer solution, as bionic for cell-based 3D bioprintable hydrogels.}, language = {en} } @article{HornbergerKisselStriegletal., author = {Hornberger, Helga and Kissel, Hannah and Striegl, Birgit and Kronseder, Matthias and Vollnhals, Florian and Christiansen, Silke H.}, title = {Bioactivity and corrosion behavior of magnesium barrier membranes}, series = {Materials and Corrosion}, volume = {73}, journal = {Materials and Corrosion}, number = {1}, publisher = {Wiley}, doi = {10.1002/maco.202112385}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-24499}, pages = {8 -- 19}, abstract = {In the current research, magnesium and its alloys have been intensively studied as resorbable implant materials. Magnesium materials combine their good mechanical properties with bioactivity, which make them interesting for guided bone regeneration and for the application as barrier membranes. In this study, the in vitro degradation behavior of thin magnesium films was investigated in cell medium and simulated body fluid. Three methods were applied to evaluate corrosion rates: measurements of (i) the gaseous volume evolved during immersion, (ii) volume change after immersion, and (iii) polarization curves. In this comparison, measurements of H2 development in Dulbecco's modified Eagle's medium showed to be the most appropriate method, exhibiting a corrosion rate of 0.5 mm·year-1. Observed oxide and carbon contamination have a high impact on controlled degradation, suggesting that surface treatment of thin foils is necessary. The bioactivity test showed positive results; more detailed tests in this area are of interest.}, language = {en} } @article{KloiberAnetsbergerSchultheissetal., author = {Kloiber, Jessica and Anetsberger, Viktoria and Schultheiß, Ulrich and Hornberger, Helga}, title = {High quality surfaces of magnesium alloy AZ31 by adjusting appropriate electropolishing parameters}, series = {Electrochimica Acta}, volume = {513}, journal = {Electrochimica Acta}, publisher = {Elsevier}, doi = {10.1016/j.electacta.2024.145547}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-79298}, language = {en} } @article{KloiberSchultheissHornberger, author = {Kloiber, Jessica and Schultheiß, Ulrich and Hornberger, Helga}, title = {Impact of heat treatment on the surface quality of electropolished WE43 alloy}, series = {Materials Letters}, volume = {397}, journal = {Materials Letters}, publisher = {Elsevier BV}, issn = {0167-577X}, doi = {10.1016/j.matlet.2025.138821}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-83512}, pages = {5}, abstract = {In this study, the Mg alloy WE43 was solution annealed and precipitation hardened prior to electropolishing to evaluate the effects of different microstructures on the electropolishing result. While coarsely distributed precipitates led to surfaces showing wavy structures and dents after electropolishing, a uniform microstructure resulted in an even finish of the surface. The homogenization and refinement of the microstructure by heat treatment is a method to ensure improved electropolished surfaces of Mg materials}, language = {en} } @article{LooNagarajuPathivadaetal., author = {Loo, Xuyan and Nagaraju, Bhavana and Pathivada, Sai and Bartsch, Alexander and Schratzenstaller, Thomas and Sattler, Robert and Monkman, Gareth J.}, title = {Electrical properties of bisphenol-A-free magnetoactive borosilicate polymers}, series = {AIP Advances}, volume = {14}, journal = {AIP Advances}, number = {5}, publisher = {AIP Publishing}, issn = {2158-3226}, doi = {10.1063/5.0203017}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-72936}, abstract = {The recent REACH regulations require the elimination of bisphenol-A and titanium dioxide from commercially available boron-based polymers. This has led to changes in some of the mechanical characteristics, which strongly influence the properties of magnetoactive borosilicate polymers. This work delivers results on the electrical properties and discusses some implications for future research using bisphenol-A and titanium-dioxide-free substitutes.}, language = {en} } @article{TauwaldErzingerQuadrioetal., author = {Tauwald, Sandra Melina and Erzinger, Florian and Quadrio, Maurizio and R{\"u}tten, Markus and Stemmer, Christian and Krenkel, Lars}, title = {Tomo-PIV in a patient-specific model of human nasal cavities: a methodological approach}, series = {Measurement Science and Technology}, volume = {35}, journal = {Measurement Science and Technology}, number = {5}, publisher = {IOP Publishing}, doi = {10.1088/1361-6501/ad282c}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-70393}, abstract = {The human nose serves as the primary gateway for air entering the respiratory system and plays a vital role in breathing. Nasal breathing difficulties are a significant health concern, leading to substantial healthcare costs for patients. Understanding nasal airflow dynamics is crucial for comprehending respiratory mechanisms. This article presents a detailed study using tomo-Particle Image Velocimetry (PIV) to investigate nasal airflow dynamics while addressing its accuracy. Embedded in the OpenNose project, the work described aims to provide a validation basis for different numerical approaches to upper airway flow. The study includes the manufacturing of a transparent silicone model based on a clinical CT scan, refractive index matching to minimize optical distortions, and precise flow rate adjustments based on physiological breathing cycles. This method allows for spatial high-resolution investigations in different regions of interest within the nasopharynx during various phases of the breathing cycle. The results demonstrate the accuracy of the investigations, enabling detailed analysis of flow structures and gradients. This spatial high-resolution tomo-PIV approach provides valuable insights into the complex flow phenomena occurring during the physiological breathing cycle in the nasopharynx. The study's findings contribute to advancements in non-free-of-sight experimental flow investigation of complex cavities under nearly realistic conditions. Furthermore, reliable and accurate experimental data is crucial for properly validating numerical approaches that compute this patient-specific flow for clinical purposes.}, language = {en} } @article{HillebrandWestner, author = {Hillebrand, Patrick and Westner, Markus}, title = {Success factors of long-term CIOs}, series = {Information Systems and e-Business Management}, volume = {20}, journal = {Information Systems and e-Business Management}, publisher = {Springer Nature}, doi = {10.1007/s10257-021-00546-z}, pages = {79 -- 122}, abstract = {Although the average tenure of CIOs has increased over the last years, the majority of CIOs have been in their positions for only three years or less. Nevertheless, some CIOs have been successful in their position for a long time. In this study, we use tenure as a proxy for success as a CIO. The goal of this paper is to examine factors that are critical to the success of long-term CIOs. For this purpose, we created and analyzed resumes of 384 CIOs. Out of these 384, we conducted 19 interviews with CIOs from top-tier companies and collected and analyzed both qualitative and quantitative data. In the process, we were able to identify nine factors that are critical for the success (CSF) of CIOs. These factors fall into three categories. Category "Personality" includes "Accepting and embracing change" (CSF \#1), "Being perseverant to pursue long-term goals" (CSF \#2), "Anticipating the future through visionary thinking" (CSF \#3), and "Being empathetic to deal with uncertainty felt by co-workers" (CSF \#4). The "Role Fulfilment" category includes "Cross-functional involvement and integration of the IT organization" (CSF \#5), "Positioning and restructuring of the IT organization" (CSF \#6), and "Well-connected and communicative leadership" (CSF \#7). The "Organizational Environment" category consists of "Availability of skilled workforce" (CSF \#8) and "Reporting line to the CEO" (CSF \#9). CSFs 1, 2, and 3 were perceived as most important by the participating CIOs. The results may be of particular interest both to aspiring CIOs and equally their employing organizations, as they reflect what long-term CIOs value during their time in office.}, language = {en} } @article{SchoenenwaldKernViehhauseretal., author = {Schoenenwald, Alexander and Kern, Simon and Viehhauser, Josef and Schildgen, Johannes}, title = {Collecting and visualizing data lineage of Spark jobs}, series = {Datenbank-Spektrum}, volume = {21}, journal = {Datenbank-Spektrum}, number = {3}, publisher = {Springer Nature}, doi = {10.1007/s13222-021-00387-7}, pages = {179 -- 189}, abstract = {Metadata management constitutes a key prerequisite for enterprises as they engage in data analytics and governance. Today, however, the context of data is often only manually documented by subject matter experts, and lacks completeness and reliability due to the complex nature of data pipelines. Thus, collecting data lineage—describing the origin, structure, and dependencies of data—in an automated fashion increases quality of provided metadata and reduces manual effort, making it critical for the development and operation of data pipelines. In our practice report, we propose an end-to-end solution that digests lineage via (Py‑)Spark execution plans. We build upon the open-source component Spline, allowing us to reliably consume lineage metadata and identify interdependencies. We map the digested data into an expandable data model, enabling us to extract graph structures for both coarse- and fine-grained data lineage. Lastly, our solution visualizes the extracted data lineage via a modern web app, and integrates with BMW Group's soon-to-be open-sourced Cloud Data Hub.}, language = {en} }