Universität Stuttgart
Permanent URI for this communityhttps://elib.uni-stuttgart.de/handle/11682/1
Browse
39 results
Search Results
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 Strategische Themen der digitalen Transformation administrativer Prozesse an den Universitäten in Baden-Württemberg - eine kooperative Umsetzung(2021) Gerken, Jan; Hätscher, Petra; Krolopp, Heidi; Nußbaumer, Martin; Peter, Christine; Pfister, Alexander; Rehm, Simone; Rottenecker, Jürgen; Scheffer, Katrin; Schenek, Matthias; Schneider, Gerhardt; Tegelears, Miriam; Walter, Thomas; Wesner, Stefan; Windscheid, Barbara; Winter, Julia; Bohr, IngridDie Universitäten sind insgesamt im Hinblick auf die Digitalisierung ihrer Dienstleistungen bereits fortgeschritten. Hier sind insbesondere die Felder Forschung, Lehre und die administrativen Prozesse der Universitäten für Studierende positiv hervorzuheben, in denen die Landesuniversitäten auch durch Nutzung von Kooperationen bereits wichtige Ergebnisse erzielt haben. Es besteht aber weiter ein großer Handlungsbedarf insbesondere in der weiteren Digitalisierung administrativer Prozesse an den Universitäten, um den Anforderungen der Forscherinnen und Forscher, der Studierenden, der Promovierenden, der Lehrenden, des administrativen Personals und nicht zuletzt auch den Erwartungen an einen zeitgemäßen Arbeitsplatz zu entsprechen. Um die Digitale Transformation der administrativen Prozesse auf Landesebene strategisch weiterzuentwickeln, werden in diesem Papier die fünf drängendsten Themenfelder der digitalen Transformation administrativer Prozesse beschrieben. Die hier beschriebenen Themenfelder verstehen sich vollständig als Teil der Dachstrategie der Landesrektorenkonferenz, die in „Baden-Württemberg 2021-26: Digitale Zukunft der Wissenschaft gestalten“ beschrieben wurden.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 Digitalisierung der Unterschrift in Verwaltungsprozessen(2021) Bohr, Ingrid; Fuhrmeister, Ivonne; Hengel, Martin; Kuhrau, Stefan; Kurz, Daniela; Ptak, Joachim; Roll, Oliver; Schleimer, Toni; Schnell, Andreas; Spann, Christian; Weilguni, Claudia; Welte, RandolphIm Papier werden rechtliche Aspekte der Bedeutung von Unterschriften sowie technische Aspekte einer möglichen Umsetzung von digitalen Unterschriften betrachtet. Anhand von drei unterschiedlichen Prozessen - Urlaubsantrag, Bewerbung und Immatrikulation sowie Beschaffung - wendet das White-Paper die Erkenntnisse der allgemeinen Betrachtung auf konkrete Vorgänge an. Aus dem White-Paper können konkrete Digitalisierungsprojekte der administrativen Prozesse der Hochschulen abgeleitet und die Mitarbeiterinnen und Mitarbeiter der Universitäten können es als Arbeitsgrundlage nutzen.Item Open Access Curbad Cannstatt : Entwicklung der Kurmetropole(2022) Grimm, Maximilian FriedrichDiese Arbeit behandelt die kulturhistorische und städtebauliche Entwicklung eines Kurorts, der zugleich ältester sowie bevölkerungsreichster Stadtbezirk in Stuttgart und überdies industrialisiert ist. Zusätzlich wird die Problematik von Großstädten mit Kurortstruktur, Bädergeschichte und Wellnesstourismus in einem Vergleich untersucht. Im Kontext der gesunden Urbanisierung (Ökostadt/Smart City usw.) sollten die traditionellen Kurstädte in der Stadtplanung allgemein Vorbilder sein. Metropolen mit Kurbetrieb können in ihrer Entwicklung historisch wie gegenwärtig beispielhaft sein.Item Open Access Facets of specialization and its relation to career success : an analysis of U.S. sociology, 1980 to 2015(2021) Heiberger, Raphael H.; Munoz-Najar Galvez, Sebastian; McFarland, Daniel A.We investigate how sociology students garner recognition from niche field audiences through specialization. Our dataset comprises over 80,000 sociology-related dissertations completed at U.S. universities, as well as data on graduates’ pursuant publications. We analyze different facets of how students specialize - topic choice, focus, novelty, and consistency. To measure specialization types within a consistent methodological frame, we utilize structural topic modeling. These measures capture specialization strategies used at an early career stage. We connect them to a crucial long-term outcome in academia: becoming an advisor. Event-history models reveal that specific topic choices and novel combinations exhibit a positive influence, whereas focused theses make no substantial difference. In particular, theses related to the cultural turn, methods, or race are tied to academic careers that lead to mentorship. Thematic consistency of students’ publication track also has a strong positive effect on the chances of becoming an advisor. Yet, there are diminishing returns to consistency for highly productive scholars, adding important nuance to the well-known imperative of publish or perish in academic careers.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 Reallabor für nachhaltige Mobilitätskultur - Intro(Stuttgart : Reallabor für nachhaltige Mobilitätskultur - Future City Lab, 2020) Alle, Katrin; Baum, Martina; Friedrich, Markus; Klawiter, Sebastian; Lindner, Doris; Migl, Alexander; Noller, Hanna; Pfau, Natalia; Schaufler, Claudius; Staffa, Anna; Uhl, Elke; Klawiter, Sebastian; Noller, Hanna; Grehl, HeideWie wollen wir in Zukunft zusammenleben? Welche Räume und Mobilitätsformen braucht es dafür und wie können wir diese gestalten? Wie können wir Transformation aktiv voranbringen? Was bewirken Realexperimente und Provisorische Architekturen? Welche Chancen eröffnet Lehre außerhalb akademischer Räume? Welche Lehrformate brauchen wir in Zukunft? Wie kann die Stadtverwaltung diese Projekte unterstützen und von ihnen profitieren? Und welche Rolle spielen dabei Bürger*innen, Studierende, Wissenschaftler*innen, Politik und Wirtschaft? Diese und viele weitere Fragen begleiteten das Future City Lab_Universität Stuttgart - Reallabor für nachhaltige Mobilitätskultur über fünf Jahre lang. In den sechs vorliegenden Zines möchten wir ergänzend zur 2018 erschienenen Publikation "Stuttgart in Bewegung: Berichte von unterwegs" weitere Ideen und mögliche Lösungswege auf diese Fragen geben. Um das in der Anschlussförderung entstandene Wissen verfügbar zu machen, den Austausch sowie die Kommunikation zwischen Zivilgesellschaft, Forscher*innen, Interessierten und Stadtverwaltung zu stärken, bündelt das Reallabor das entstandene Wissen in eine Open-Source-Zines-Sammlung. Diese Zines genannten Hefte sind Low-Budget-Magazine, kostengünstig auf A3-Papier zu drucken und zu einfachen DIN-A4-Heften zu falten. Dadurch soll der Austausch, der Umgang und die Diskussion mit den erarbeiteten Thematiken vereinfacht und für alle Beteiligten schnell sowie kostenlos zugänglich werden. Ganz bewusst wurden die wichtigen Erkenntnisse der Projekte an den jeweiligen Anfang der Zines gestellt, um die vielfältigen Inhalte greifbar zu machen. Innerhalb der Zines wird mittels Fußnoten und farbigen Hervorhebungen auf weiterführende Literatur und verwandte Thematiken verwiesen. Um den übergeordneten Zusammenhang der einzelnen Hefte zu visualisieren, wurde in Zusammenarbeit mit dem Grafikbüro Studio Panorama eine Layoutvorlage entwickelt. Entstanden ist ein Hybrid aus wissenschaftlicher und beschreibender Aufarbeitung der zweiten Förderphase mit der Intention, Möglichkeiten zur Bearbeitung wichtiger Forschungsfragen aufzeigen und niederschwellig vermitteln zu können.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 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.