Universität Stuttgart
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Item Open Access Movement in the digital world : interdisciplinary model, processes, and methods in digital motor-cognitive health promotion - exergame research and development in collaboration at the intersection of human movement science, user experience and game design(2026) Ciemer, Celina; Schott, Nadja (Prof. Dr.)Increasing motor and cognitive inactivity presents a growing global health concern. It contributes significantly to chronic diseases, cardiovascular conditions, and cognitive decline, leads to higher mortality rates, and diminishes overall well-being and quality of life. In response, there is an urgent need for effective and motivating motor and cognitive health promotion. Exergames using motor-cognitive exercises embedded within a game context have emerged as a promising approach. However, their potential remains underexploited due to insufficient interdisciplinary collaboration and the lack of transparent, structured design practices, which hinder meaningful evaluation by generalization. In this thesis, the Co-creative Interdisciplinary Exergame design process Model and Extended Reflection (CIEMER) framework is introduced and developed to address these foundational challenges. CIEMER consists of a conceptual model that fosters shared understanding through defined relational structures, a practical design process that produces clear, interpretable outcomes, and applicable collaboration methods. This framework redefines interdisciplinary collaboration as an active relational process requiring dedicated structure. By integrating different epistemological concepts and procedures in a pluralistic approach and translating this disciplinary expertise into a shared language, CIEMER facilitates shared design and evaluation. It enables the visibility of both discipline-specific concepts and procedures as well as their translation into interdisciplinary design decisions within a shared context. CIEMER further supports the precise definition of shared exergame objectives and corresponding evaluation strategies, thereby enabling comprehensible, comparable, and reproducible insights beyond 'black-box' findings. CIEMER thus provides a foundational step toward standardizing interdisciplinary exergame design and reporting practices. The framework has been validated by designing two high-fidelity and four early-stage exergames. Both high-fidelity exergames are designed to address functional decline across motor, cognitive, sensory, and psychological domains through multidimensional training. They incorporate natural, unrestricted walking as it is a fundamental mode of human mobility. This type of walking requires the continuous integration of locomotion, postural control, and adaptation to environmental demands, forming a complex dual-task scenario that is central to real-world functioning. The first exergame is based on the clinical Trail-Walking Test and translates its dual-task structure into an urban scenario using mixed reality floor projection mapping. The second exergame integrates various unrestricted natural walking patterns within a hiking environment that reflects real-world conditions. It is implemented in fully immersive virtual reality and specifically targets fall prevention in healthy, community-dwelling older adults. This is achieved through the integration of effectiveness, enjoyment, and meaningfulness objectives of human movement science, game design, and user experience design, and supported by the results of a quasi-randomized controlled trial. Additionally, a cross-disciplinary systematic review identified key research gaps and challenges in fall prevention exergame collaborations. A novel systematic literature search framework (CRIS) was developed to enable such reviews, accommodating the highly variable nature of exergames across forms of collaboration, applications, and disciplines, addressing epistemological differences. This thesis marks a starting point for structured interdisciplinary collaboration in exergame research. This work can help future work to expand the proposed reporting practices, apply and refine the process in varied interdisciplinary and contextual settings, and further develop context-specific methods to establish robust, generalizable standards.Item Open Access A model-based framework for the assessment of energy-efficiency and CO2-mitigation measures in multi-cylinder paper drying(Stuttgart : Universität Stuttgart, Institut für Energiewirtschaft und Rationelle Energieanwendung, 2022) Godin, Hélène; Radgen, Peter (Prof. Dr.-Ing.)Thesis on the effect of energy-efficiency and CO2-mitigation measures in multi-cylinder paper drying.Item Open Access Data-driven modelling of neuromechanical adaptation in skeletal muscles in response to isometric exercise(Stuttgart : Institute for Modelling and Simulation of Biomechanical Systems, Chair of Continuum Biomechanics and Mechanobiology, University of Stuttgart, 2022) Altan, Neriman Ekin; Röhrle, Oliver (Prof., PhD)This study aims to model the changes in the behaviour of motor neurons of the vastus lateralis in response to unilateral isometric knee extension exercise (UIKEE). For this, the phenomenological motor control model by Fuglevand et al. (1993) has been used. Input parameters for this model have been calibrated against data from experimental studies available in literature by using Bayesian updating. The pre-exercise state of the motor neuron pool of the muscle describing the recruitment behaviour as well as the contractile properties of the motor neurons have been constructed. Data collected from a systematic review on the change in isometric strength due to UIKEE has been modelled using Bayesian lonigutidinal model-based meta-analysis. Using the model of the change in isometric strength, increase in the average motor neuron discharge rate following UIKEE has been quantified.Item Open Access Untersuchung einer Augmented Reality Kollaborationssoftware in der verteilten agilen Arbeitsweise der Automobilentwicklung(2024) Dyhringer, Robert; Resch, Michael (Prof. Dr.-Ing. Dr. h.c. Dr. h.c. Prof. e.h)Der Begriff Metaverse motiviert seit 2021 neue Forschung in der Wissenschaft, insbesondere in der Automobilentwicklung. Die Kombination von agilen Arbeitsweisen und verteilter Zusammenarbeit wirft neue Herausforderungen auf, die durch den Einsatz einer kollaborativen Augmented Reality Software bewältigt werden können. Eine methodisch entwickelte Software und wissenschaftliche Studien zeigen in dieser Arbeit, dass die Technologie der Augmented Reality die gleichberechtigte Gruppenarbeit und die Kommunikation in einem agilen Setup verbessern kann.Item Open Access Housing adjustment to handle natural hazards : proactive urban development planning for an effective response to natural hazards and to "build back better" in recovery, rehabilitation, and reconstruction - on the case of Banda Aceh, Indonesia(2021) Lucas, Sabrina; Schönwandt, Walter L. (Prof. Dr.-Ing. Dipl.-Ing. Dipl.-Psych.)Natural hazards, including climatological, meteorological, hydrological, and geophysical hazards can have a devastating impact on human life, the built environment, urban development, and economy. A lack of money and resources, inadequate planning laws and regulations as well as a lack of effective monitoring strategies, are reasons why people in developing countries are particularly vulnerable to the impact of natural hazards. In many cases, there is a lack of information and knowledge about what can be done to appropriately adjust housing, comprising the immediate physical environment, both within and outside of buildings where people live, and which serve as a shelter from external influences. The present thesis investigates the need for pre-disaster housing adjustment strategies as a necessary contribution of urban development planning at a local level. This was achieved through systematic interviews and field studies in the post disaster study area Banda Aceh, Indonesia. Two instruments for pre-disaster planning are introduced: ‘Proactive urban development planning as pre-disaster protection’, a systematic risk management approach, before a disaster strikes as part of the everyday planning process; and a ‘reconstruction template’ to prepare for the worst-case scenario. With these two instruments, not only the quality of reconstruction projects can be improved but, in long-term urban development planning, housing can be adjusted to natural hazards. This approach is based on the UNISDR (United Nations International Strategy for Disaster Risk Reduction) Sendai framework for Disaster Risk Reduction 2015-2030 and forms a bridge between post-disaster reconstruction and long-lasting urban development.Item Open Access Miscibility, viscoelastic reinforcement, and transport properties of blend membranes based on sulfonated poly(phenylene sulfone)s(2021) Saatkamp, Torben; Maier, Joachim (Prof. Dr.)Chemical energy that hydrogen may generate during combustion and the corresponding electrical energy are interconvertible by means of a fuel cell (FC) and by the electrolysis of water (WE), which allows for the utilization of the complementary nature of these two key energy vectors towards energy sustainability. A proton exchange membrane (PEM) made from an ionomer is commonly employed as the electrolyte in mobile fuel cell applications and in water electrolyzers that require dynamic operability and pressurized product gases. New PEM materials are needed to increase performance, reduce environmental impact, and allow for a more targeted design of PEMFC and PEMWE systems, all of which is in some way limited by the use of the established perfluorosulfonic acid (PFSA) type ionomers. This work’s focus lies on sulfonated poly(phenylene sulfone)s (sPPS), a unique group of fluorine-free cation conducting ionomers. They are unique in terms of their chemical stability and transport properties, however, typical in terms of their salt-like brittleness in the dry state and extensive swelling at high humidity and in water. To make the unique properties of sPPS available in application, the goal of this work is to take a comprehensive approach to their viscoelastic reinforcement. Therefore, the structure of this thesis entails three related aspects along the process from pure materials to the optimization of robust PEMs for application. The first chapter focuses on the optimization of the intrinsic viscoelastic properties of a particularly suited sPPS (termed S360, with IEC 2.78 meq g-1, EW 360 g mol-1) which lays the groundwork for reliable and systematic further development. To achieve this, relevant properties of S360 are first characterized and viscoelastic shortcomings as seen in water uptake measurements and tensile tests under dry conditions (≤ 30% relative humidity, RH) discussed. The step-growth polymerization of S360 is optimized after finding significant inorganic contamination retained in the established purification process of the widely used monomer sulfonated difluorodiphenyl sulfone (sDFDPS), allowing for the preparation of the ionomer in reproducible high molecular weight. Relevant properties of high molecular weight S360 are characterized and an enhancement of mechanical properties at 30% RH as well as when submerged in water is found. Access to reproducible high quality of S360 enables its first-time use and study as a PEM in a completely fluorine-free WE cell. At 80 °C, record performance amongst fluorine free electrolytes in PEMWEs of 3.48 A cm-2 at 1.8 V is achieved, showcasing the potential of sPPS for application. The second chapter entails the identification and better understanding of a suitable and versatile reinforcement concept for creating robust membranes based on sPPS. To achieve this, the established homogeneously miscible acid-base polymer blends of sulfonated ionomers with poly(benzimidazole) (PBI, and its derivatives PBIO and PBIOO) are discussed in-depth and chosen for later systematic optimization in combination with sPPS. Since the origin of miscibility in PBI blends with sulfonated ionomers is insufficiently described in literature and could facilitate targeted design of new blend components, a model acid-base polymer blend system comprising pyridine-functionalized poly(sulfone) (PSU) is created. Pyridine groups of different basicity tethered to PSU in varying concentration are used to investigate the effect that interpolymer acid-base interaction strength and concentration have on miscibility in blends with 80 wt% S360, as derived from the blend membranes’ cross-sectional SEMs. High mutual compatibility is achieved at high concentration of weak interpolymer interaction, which is interpreted with regards to the observed miscibility in PBI blends. Based on the derived role that hydrogen bonds may play in PBI blends, the difference of interpolymer interaction in solution (during membrane formation) and in the dry membrane is described. This could enable the development of new blend concepts in the future. An exemplary miscible blend that comprises interpolymer hydrogen bonds only in solution but not in the final membrane is shown. The third chapter describes the optimization and balance of properties in the previously described polymer blends with PBIO, following the goal to prepare membranes which can be evaluated in fuel cells and fabricated on a wider scale in order to bring the attractive properties of sPPS into application. To achieve this, S360-blend membranes of varying PBIO content are characterized with regard to conductivity and mechanical properties in various conditions. High mechanical robustness is achieved in S360 blends with 30 wt% PBIO but is accompanied by dramatic reduction of conductivity, due to the charge-consuming acid-base interaction. The findings are translated into blends with fully sulfonated sPPS (termed S220, with IEC 4.54 meq g-1, EW 220 g mol-1) which allows for the creation of membranes that combine mechanical toughness with high conductivity at a ratio of 25 wt% PBIO in S220, making the material suited for production on a commercial casting line and fuel cell testing. Membranes based on S360 that comprise 15 wt% PBIO are designated for further studies in PEMWEs, where membrane requirements differ significantly from that in PEMFCs, highlighting the versatility of the reinforcement approach chosen in this work. Finally, first fuel cell tests of thin spray coated PBIO blend membranes are conducted, and initial durability testing of sPPS-based membranes in fuel cells is possible. Overall, the results presented in this work are strongly interrelated which underlines the importance of comprehensiveness in the successful viscoelastic reinforcement of sulfonated poly(phenylene sulfone)s. Ultimately, the blend membranes resulting from this work can be used as a platform for further development of sPPS-based PEMs in the future.Item Open Access Technologieakzeptanz von virtuellen Lern- und Arbeitsumgebungen(2021) Pletz, Carolin; Zinn, Bernd (Prof. Dr.)Mit dem Einsatz innovativer Technologien in Lern- und Arbeitsprozessen werden vor dem Hintergrund der Digitalisierung und Industrie 4.0 multiple Potenziale verbunden. Insbesondere immersive virtuelle Lern- und Arbeitsumgebungen (Virtual Reality, kurz IVR) bieten vielversprechende Möglichkeiten, um das Lernen und Arbeiten gewinnbringend zu unterstützen. Unter IVR werden computergenerierte Darstellungen verstanden, welche dreidimensional und interaktiv sind. Die Nutzenden können über natürliche Benutzerschnittstellen regelrecht in die virtuelle Umgebung „eintauchen“. Der in der Arbeit bilanzierte Forschungsstand zeigt, dass zu Beginn der Forschungsbemühungen allerdings nur wenig über die Technologieakzeptanz von IVR und den entsprechenden fördernden und hemmenden Faktoren bekannt ist. Unter der Technologieakzeptanz wird die „positive Annahmeentscheidung einer Innovation durch die [Anwenderinnen und] Anwender“ (Simon, 2001, S. 89) verstanden. In Anbetracht dieser Forschungslücke besteht das zentrale Forschungsvorhaben der vorliegenden Arbeit deshalb in der Generierung eines Beschreibungs- und Erklärungswissens zur Technologieakzeptanz von IVR bei (potenziellen) Nutzerinnen und Nutzern. Ein theoretischer Rahmen zur Digitalisierung der Arbeitswelt, zu Virtual Reality Technologien und zur Technologieakzeptanz sowie eine Übersicht über den entsprechenden empirischen Forschungsstand führen in die Thematik ein. Die Arbeit umfasst vier empirische Studien zur Untersuchung der Technologieakzeptanz von IVR. In der ersten Studie werden die theoretischen Annahmen des Technology Acceptance Models (TAM) in Bezug auf die Technologieakzeptanz von IVR empirisch geprüft. Das TAM geht davon aus, dass die Nutzungsintention von Informationstechnologien hauptsächlich von der wahrgenommenen Nützlichkeit und Benutzerfreundlichkeit beeinflusst wird. Studie 1 untersucht in diesem Zusammenhang die Technologieakzeptanz und die nutzerbezogenen Faktoren Alter und Vorerfahrung mit der Technologie im Rahmen einer quantitativen Fragebogenerhebung mit (potenziellen) Nutzerinnen und Nutzern von IVR. Die zweite Studie fokussiert die Technologieakzeptanz eines virtuellen Verkaufsraums und bezieht neben den Kernfaktoren des TAM die soziale Norm, wahrgenommene Verhaltenskontrolle sowie die organisationsbezogenen Faktoren Unterstützung durch die Führung, Anwendertraining und Anwendersupport in die Betrachtung ein. Die Datenerhebung erfolgt ebenfalls mittels eines quantitativen Fragebogens. In der dritten Studie wird eine virtuelle Lernanwendung für Bedienerschulungen formativ im Hinblick auf die Technologieakzeptanz, User Experience und den Lerntransfer von virtuell gelerntem Handlungswissen auf reale Tätigkeiten mittels einer qualitativen Videoanalyse evaluiert. Die vierte Studie zielt auf die Identifikation von weiteren nutzerbezogenen, organisationsbezogenen und insbesondere technologiespezifischen fördernden und hemmenden Faktoren im Rahmen einer qualitativen Interviewstudie mit Experten ab. Die Ergebnisse zeigen, dass das TAM auch als geeignete Grundlage zur Untersuchung der Technologieakzeptanz von IVR herangezogen werden kann und die wahrgenommene Nützlichkeit sowie Benutzerfreundlichkeit einen Einfluss auf die Nutzungsintention haben (Studie 1). Ebenso beeinflusst die wahrgenommene Verhaltenskontrolle die Nutzungsintention und die organisationalen Faktoren hängen positiv mit den TAM-Faktoren zusammen (Studie 2). Es wird verdeutlicht, dass mit der Untersuchung innovativer Technologien auch neuartige methodische Zugänge in Forschungsbemühungen einhergehen müssen (Studie 3). Weitere nutzerbezogene, organisationsbezogene und technologiespezifische Einflussfaktoren auf die Technologieakzeptanz werden für den Einsatz von IVR in Lehr-Lernkontexten identifiziert (Studie 4). Zusammenfassend lassen sich auf der Basis der eigenen Forschungsergebnisse und unter Berücksichtigung der Limitationen praxisrelevante Ansatzpunkte zur Steigerung der Technologieakzeptanz von IVR ableiten.Item Open Access Enzymkatalysierte regioselektive N-Methylierung und N-Alkylierung von Pyrazolen(2021) Bengel, Ludwig L.; Hauer, Bernhard (Prof. Dr.)Item Open Access Human and computational measurement of lexical semantic change(2023) Schlechtweg, Dominik; Schulte im Walde, Sabine (apl. Prof. Dr.)Human language changes over time. This change occurs on several linguistic levels such as grammar, sound or meaning. The study of meaning changes on the word level is often called 'Lexical Semantic Change' (LSC) and is traditionally either approached from an onomasiological perspective asking by which words a meaning can be expressed, or a semasiological perspective asking which meanings a word can express over time. In recent years, the task of automatic detection of semasiological LSC from textual data has been established as a proper field of computational linguistics under the name of 'Lexical Semantic Change Detection' (LSCD). Two main factors have contributed to this development: (i) The 'digital turn' in the humanities has made large amounts of historical texts available in digital form. (ii) New computational models have been introduced efficiently learning semantic aspects of words solely from text. One of the main motivations behind the work on LSCD are their applications in historical semantics and historical lexicography, where researchers are concerned with the classification of words into categories of semantic change. Automatic methods have the advantage to produce semantic change predictions for large amounts of data in small amounts of time and could thus considerably decrease human efforts in the mentioned fields while being able to scan more data and thus to uncover more semantic changes, which are at the same time less biased towards ad hoc sampling criteria used by researchers. On the other hand, automatic methods may also be hurtful when their predictions are biased, i.e., they may miss numerous semantic changes or label words as changing which are not. Results produced in this way may then lead researchers to make empirically inadequate generalizations on semantic change. Hence, automatic change detection methods should not be trusted until they have been evaluated thoroughly and their predictions have been shown to reach an acceptable level of correctness. Despite the rapid growth of LSCD as a field, a solid evaluation of the wealth of proposed models was still missing at the onset of this thesis. The reasons were multiple, but most importantly there was no annotated benchmark test set available. This thesis is thus concerned with the process of providing such an evaluation for LSCD, including • the definition of the basic concepts and tasks, • the development and validation of data annotation schemes with humans, • the annotation of a multilingual benchmark test set, • the evaluation of computational models on the benchmark, their analysis and improvement, as well as • an application of the developed methods to showcase their usefulness in the targeted fields (historical semantics and lexicography).Item Open Access Chancen und Risiken von Aufstieg und Macht : politisch-gesellschaftliche Wirklichkeit in den "Märchen" der Gründerzeit (1871-1890)(2024) Berger, Anna; Potthast, Barbara (apl. Prof. Dr.)Die vorliegende Arbeit geht davon aus, dass sich - ohne einen Allgemeinheitsanspruch zu erheben - in einem großen Teil der in der Gründerzeit veröffentlichten ‚Märchen‘ Bezüge zur zeitgenössischen politischen, wirtschaftlichen und sozialen Wirklichkeit am Ende des 19. Jahrhunderts zeigen. Anhand konkreter Textbeispiele werden diese modernen Elemente herausgearbeitet und es wird gezeigt, auf welche Art und Weise sie mit den Merkmalen der Gattung ‚Märchen‘ verknüpft werden und welche Funktion sie darin erfüllen. Als Untersuchungszeitraum werden die Jahre 1871 bis 1890 zugrunde gelegt. Dabei setzt sich das Textkorpus einerseits aus Prosatexten zusammen, die in der von Julius Lohmeyer herausgegebenen Zeitschrift „Deutsche Jugend“ im Zeitraum von 1873 bis 1885 abgedruckt worden sind, und andererseits aus Märchenbüchern und Beiträgen in Dichtermärchen-Sammlungen. Dabei zeigt sich auf der einen Seite, dass in einigen als ‚Märchen‘ titulierten Texten das zentrale Merkmal des ‚Wunderbaren‘ fehlt. Aus literaturwissenschaftlicher Sicht handelt es sich um (realistische) Erzählungen, die sich paratextuell selbst als ‚Märchen‘ ausweisen. Auf der anderen Seite beinhaltet das Textkorpus zahlreiche Erzählungen, die eine Mischung aus Realismus und märchentypischen Kennzeichen - sei es den Handlungsablauf, das Personal und die Requisiten oder den Märchenstil betreffend - aufweisen. Da diesen im ausgehenden 19. Jahrhundert veröffentlichten Texten in der Forschung bisher nur wenig Aufmerksamkeit im Speziellen gewidmet wurde, liegt der Schwerpunkt dieser literaturwissenschaftlichen Untersuchung auf der Präsentation, der Analyse und dem Vergleich ausgewählter, größtenteils in Vergessenheit geratener, deutschsprachiger ‚Märchen‘ der Gründerzeit. In Anbetracht der Materialfülle wurden bei der Auswahl der Erzählungen die Themen-Schwerpunkte ‚Aufstiegschancen und Abstiegsängste‘ und ‚Machtgewinn und Machtverlust‘ gesetzt, die in einer Wechselbeziehung zueinander stehen. Diese beiden Themenbereiche zeichnen sich besonders deutlich in den untersuchten Prosatexten ab.