@phdthesis{Wills,
  author    = {Wills, Nadine},
  title     = {Modell bedarfsorientierter Leistungserbringung im FM auf Grundlage von Sensortechnologien und BIM},
  publisher = {Eigenverlag der Professur Baubetrieb und Bauverfahren},
  address   = {Weimar},
  doi       = {10.25643/bauhaus-universitaet.4924},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230214-49248},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {171},
  abstract  = {W{\"a}hrend der Digitalisierung im Bauwesen insbesondere im Bereich der Planungs- und Errichtungsphase von Bauwerken immer gr{\"o}ßere Aufmerksamkeit zuteilwird, ist das digitale Potenzial im Facility Management weit weniger ausgesch{\"o}pft, als dies m{\"o}glich w{\"a}re. Vor dem Hintergrund, dass die Bewirtschaftung von Geb{\"a}uden jedoch einen wesentlichen Kostenanteil im Lebenszyklus darstellt, ist eine Fokussierung auf digitale Prozesse im Geb{\"a}udebetrieb erforderlich. Im Facility Management werden Dienstleistungen h{\"a}ufig verrichtungsorientiert, d. h. nach statischen Intervallen, oder bedarfsorientiert erbracht. Beide Arten der Leistungserbringung weisen Defizite auf, beispielweise weil T{\"a}tigkeiten auf Basis definierter Intervalle erbracht werden, ohne dass eine Notwendigkeit besteht oder weil bestehende Bedarfe mangels M{\"o}glichkeiten der Bedarfsermittlung nicht identifiziert werden. Speziell die Definition und Ermittlung eines Bedarfs zur Leistungserbringung ist h{\"a}ufig subjektiv gepr{\"a}gt. Auch sind Dienstleister oft nicht in fr{\"u}hen Phasen der Geb{\"a}udeplanung involviert und erhalten f{\"u}r ihre Dienstleistungen notwendige Daten und Informationen erst kurz vor Inbetriebnahme des zu betreibenden Geb{\"a}udes. Aktuelle Ans{\"a}tze des Building Information Modeling (BIM) und die zunehmende Verf{\"u}gbarkeit von Sensortechnologien in Geb{\"a}uden bieten Chancen, die o. g. Defizite zu beheben. In der vorliegenden Arbeit werden deshalb Datenmodelle und Methoden entwickelt, die mithilfe von BIM-basierten Datenbankstrukturen sowie Auswertungs- und Entscheidungsmethodiken Dienstleistungen der Geb{\"a}udebewirtschaftung objektiviert und automatisiert ausl{\"o}sen k{\"o}nnen. Der Fokus der Arbeit liegt dabei auf dem Facility Service der Reinigungs- und Pflegedienste des infrastrukturellen Facility Managements. Eine umfangreiche Recherche etablierter Normen und Standards sowie {\"o}ffentlich zug{\"a}nglicher Leistungsausschreibungen bilden die Grundlage der Definition erforderlicher Informationen zur Leistungserbringung. Die identifizierten statischen Geb{\"a}ude- und Prozessinformationen werden in einem relationalen Datenbankmodell strukturiert, das nach einer Darstellung von Messgr{\"o}ßen und der Beschreibung des Vorgehens zur Auswahl geeigneter Sensoren f{\"u}r die Erfassung von Bedarfen, um Sensorinformationen erweitert wird. Um Messwerte verschiedener und bereits in Geb{\"a}uden existenten Sensoren f{\"u}r die Leistungsausl{\"o}sung verwenden zu k{\"o}nnen, erfolgt die Implementierung einer Normierungsmethodik in das Datenbankmodell. Auf diese Weise kann der Bedarf zur Leistungserbringung ausgehend von Grenzwerten ermitteln werden. Auch sind Verkn{\"u}pfungsmethoden zur Kombination verschiedener Anwendungen in dem Datenbankmodell integriert. Zus{\"a}tzlich zur direkten Ausl{\"o}sung erforderlicher Aktivit{\"a}ten erm{\"o}glicht das entwickelte Modell eine opportune Ausl{\"o}sung von Leistungen, d. h. eine Leistungserbringung vor dem eigentlich bestehenden Bedarf. Auf diese Weise k{\"o}nnen t{\"a}tigkeits{\"a}hnliche oder r{\"a}umlich nah beieinander liegende T{\"a}tigkeiten sinnvoll vorzeitig erbracht werden, um f{\"u}r den Dienstleister eine Wegstreckeneinsparung zu erm{\"o}glichen. Die Arbeit beschreibt zudem die f{\"u}r die Auswertung, Entscheidungsfindung und Auftrags{\"u}berwachung ben{\"o}tigen Algorithmen. Die Validierung des entwickelten Modells bedarfsorientierter Leistungserbringung erfolgt in einer relationalen Datenbank und zeigt simulativ f{\"u}r unterschiedliche Szenarien des Geb{\"a}udebetriebs, dass Bedarfsermittlungen auf Grundlage von Sensortechnologien erfolgen und Leistungen opportun ausgel{\"o}st, beauftragt und dokumentiert werden k{\"o}nnen.},
  subject      = {Facility-Management},
  language  = {de}
}
@phdthesis{Jaouadi,
  author    = {Jaouadi, Zouhour},
  title     = {Pareto and Reliability-Oriented Aeroelastic Shape Optimization of Bridge Decks},
  doi       = {10.25643/bauhaus-universitaet.4935},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230303-49352},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {167},
  abstract  = {Due to the development of new technologies and materials, optimized bridge design has recently gained more attention. The aim is to reduce the bridge components materials and the CO2 emission from the cement manufacturing process. Thus, most long-span bridges are designed to be with high flexibility, low structural damping, and longer and slender spans. Such designs lead, however, to aeroelastic challenges. Moreover, the consideration of both the structural and aeroelastic behavior in bridges leads to contradictory solutions as the structural constraints lead to deck prototypes with high depth which provide high inertia to material volume ratios. On the other hand, considering solely the aerodynamic requirements, slender airfoil-shaped bridge box girders are recommended since they prevent vortex shedding and exhibit minimum drag. Within this framework comes this study which provides approaches to find optimal bridge deck cross-sections while considering the aerodynamic effects. Shape optimization of deck cross-section is usually formulated to minimize the amount of material by finding adequate parameters such as the depth, the height, and the thickness and while ensuring the overall stability of the structure by the application of some constraints. Codes and studies have been implemented to analyze the wind phenomena and the structural responses towards bridge deck cross-sections where simplifications have been adopted due to the complexity and the uniqueness of such components besides the difficulty of obtaining a final model of the aerodynamic behavior. In this thesis, two main perspectives have been studied; the first is fully deterministic and presents a novel framework on generating optimal aerodynamic shapes for streamlined and trapezoidal cross-sections based on the meta-modeling approach. Single and multi-objective optimizations were both carried out and a Pareto Front is generated. The performance of the optimal designs is checked afterwards. In the second part, a new strategy based on Reliability-Based Design Optimization (RBDO) to mitigate the vortex-induced vibration (VIV) on the Trans-Tokyo Bay bridge is proposed. Small changes in the leading and trailing edges are presented and uncertainties are considered in the structural system. Probabilistic constraints based on polynomial regression are evaluated and the problem is solved while applying the Reliability Index Approach (RIA) and the Performance Measure Approach (PMA). The results obtained in the first part showed that the aspect ratio has a significant effect on the aerodynamic behavior where deeper cross-sections have lower resistance against flutter and should be avoided. In the second part, the adopted RBDO approach succeeded to mitigate the VIV, and it is proven that designs with narrow or prolonged bottom-base length and featuring an abrupt surface change in the leading and trailing edges can lead to high vertical vibration amplitude. It is expected that this research will help engineers with the selections of the adequate deck cross-section layout, and encourage researchers to apply concepts of optimization regarding this field and develop the presented approaches for further studies.},
  subject      = {Gestaltoptimierung},
  language  = {en}
}
@phdthesis{Weise,
  author    = {Weise, Franziska},
  title     = {Erfolgskritische Faktoren in exemplarischen Building Information Modeling Anwendungsf{\"a}llen: Eine Analyse unter der Beachtung schleppender Digitalisierung und organisationaler Ver{\"a}nderungen},
  publisher = {Eigenverlag der Professur Baubetrieb und Bauverfahren},
  address   = {Weimar},
  doi       = {10.25643/bauhaus-universitaet.4928},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230302-49281},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  abstract  = {Die fortschreitende Digitalisierung l{\"a}sst innovative bauprojekt- und unternehmensinterne Workflows sowie Organisationssysteme entstehen. In diesem Zusammenhang ist die digitale Fortentwicklung durch Building Information Modeling [BIM] als Ver{\"a}nderungsprozess zu definieren, der Organisationsstrukturen nachhaltig umformen wird. BIM ist die f{\"u}hrende digitale Arbeitsmethodik im Bauwesen, die entwurfs-, ausf{\"u}hrungs- und bauprojektbezogenen Belangen gerecht werden kann. Die deutsche Bauwirtschaft ist im Vergleich zu anderen Branchen jedoch als digital r{\"u}ckst{\"a}ndig zu betrachten. Sie ist durch einen Markt gekennzeichnet, an dem kleine und mittelst{\"a}ndische Unternehmen [KMU] in hoher Zahl vertreten sind. Aufgrund von Anwendungsunkenntnis der kleinen und mittelst{\"a}ndischen Unternehmen fehlt der fl{\"a}chendeckende und durchg{\"a}ngige BIM-Einsatz in Projekten. Mit dem Fokus auf dem Bauprojekt als tempor{\"a}rer Organisation adressiert der vorliegende Forschungsschwerpunkt die Schaffung eines realistischen Abbilds erprobter BIM-Anwendungsf{\"a}lle in Modellprojekten. Herausgearbeitet werden derzeit bestehende BIM-Herausforderungen f{\"u}r Erstanwender, die die durchg{\"a}ngige BIM-Anwendung in Deutschland bisher hemmen. Die Forschungsarbeit fokussiert sich auf die Evaluation erfolgskritischer Faktoren [ekF] in BIM-Anwendungsf{\"a}llen [AWF] im Rahmen einer qualitativen Inhaltsanalyse. Die digitale Transformation birgt strukturrelevante Ver{\"a}nderungsdeterminanten f{\"u}r Organisationen durch die BIM-Anwendung und außerdem Herausforderungen, die in der Anwendungsfallforschung betrachtet werden. Die Zielstellung ist dreiteilig. Ein entwickeltes BIM-Strukturmodell erfasst die aktuelle Richtlinienarbeit sowie Standardisierung und stellt dadurch den Rahmen notwendiger BIM-Strukturen im Bauprojekt auf. Aus dem Strukturmodell ist ein Modell zur Pr{\"u}fung von Anwendungsfallrisiken abgeleitet worden. Dieses wird auf gezielt recherchierte BIM-Modellprojekte in Deutschland angewendet, um aus den erfolgskritischen Faktoren der darin praktizierten BIM-Anwendungsf{\"a}lle eine ekF-Risikomatrix abzuleiten. Daraus geht ein unterst{\"u}tzendes BIM-Anwendungsinstrument in Form von BPMN-Abl{\"a}ufen f{\"u}r KMU hervor. Resultierend aus der Verbindung des BIM-Strukturmodels und der Anwendungsfallanalyse wird in den einzelnen Ablauf{\"u}bersichten eine Risikoverortung je Anwendungsfall kenntlich gemacht. Unternehmen ohne BIM-Anwendungsexpertise in Bauprojektorganisationen erhalten auf diese Weise einen instrumentellen und niederschwelligen Zugang zu BIM, um die kollaborativen und wirtschaftlichen Vorteile der digitalen Arbeitsmethodik nutzen zu k{\"o}nnen.},
  subject      = {Building Information Modeling},
  language  = {de}
}
@phdthesis{Hunger,
  author    = {Hunger, Francis},
  title     = {Die Form der Datenbank},
  doi       = {10.25643/bauhaus-universitaet.4936},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230306-49362},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {424},
  abstract  = {Datenbanken sind heute die wichtigste Technik zur Organisation und Verarbeitung von Daten. Wie wurden sie zu einer der allgegenw{\"a}rtigsten und gleichzeitig unsichtbarsten Praxis, die menschliche Zusammenarbeit erm{\"o}glicht? Diese Studie beginnt mit einer historiographischen Erkundung der zentralen medialen Konzepte von Datenbanken und m{\"u}ndet in das praxeologische Konzept der "Daten als Formation", kurz: In-Formation. Der erste Hauptteil befasst sich mit der Formatierung von Daten durch die Verarbeitung strukturierter Daten mittels relationaler Algebra. Es wird erarbeitet, auf welche Weise Struktur neues Wissen schafft. Im zweiten Teil wird er{\"o}rtert, wie Datenbanken durch den diagrammatisch-epistemischen Raum der Tabelle operationalisiert werden. Drittens untersucht die Studie Transaktionen als Erkl{\"a}rungen daf{\"u}r, wie Daten und reale Handlungen koordiniert und synchronisiert werden k{\"o}nnen. Im zweiten Hauptteil wird untersucht, wie relationale Datenbanken zunehmend zum Zentrum von Softwareanwendungen und Infrastrukturen wurden, wobei der Schwerpunkt auf wirtschaftlichen Praktiken liegt. In einem vergleichenden Ansatz wird anhand von Fallstudien in der DDR der 1970er bis 1990er Jahren die Frage gestellt, ob es eine „sozialistische" Datenbankmanagement-Software gegeben hat. Dabei werden die „westlichen" Produktionsdatenbanken BOMP, COPICS und MAPICS (IBM) sowie R2 (SAP) im Zusammenspiel mit den ostdeutschen Sachgebietsorientierten Programmiersystemen (SOPS) von Robotron diskutiert. Schließlich untersucht dieser Teil, wie die DDR ihr eigenes relationales Datenbankmanagementsystem, DABA 1600, entwickelte und dabei „westliche" Technologie neu interpretierte. Das abschließende Kapitel fasst die Konzepte der relationalen Datenbanken als heute wichtigsten Datenorganisationstechnik zusammen. Es er{\"o}rtert, inwiefern es m{\"o}glich ist, die historiographische Erz{\"a}hlung {\"u}ber die Entstehung von Datenbankmanagementsystemen und ihre Folgen f{\"u}r die Geschichte der Informatik zu dezentrieren. Es schließt mit der Erkenntnis, dass {\"o}stliche und westliche Medien der Kooperation sich in Form und Funktion erstaunlich {\"a}hnlich sind, beide wurzeln in den tiefen Genealogien von organisatorischen und wissensbildenden Datenpraktiken. Neben dieser medienwissenschaftlichen Arbeit besteht die Dissertation aus einem k{\"u}nstlerischen Teil, der dokumentiert wird: Anhand einer Reihe von Vlogs erkundet die fiktionale Figur „Data Proxy" aktuelle Daten{\"o}kologien.},
  subject      = {Medientheorie},
  language  = {de}
}
@phdthesis{Gapševičius,
  author    = {Gapševičius, Mindaugas},
  title     = {Aesthetics of Maker Culture: the Active Role of the Audience},
  doi       = {10.25643/bauhaus-universitaet.4939},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230313-49396},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {206},
  abstract  = {In this work, practice-based research is conducted to rethink the understanding of aesthetics, especially in relation to current media art. Granted, we live in times when technologies merge with living organisms, but we also live in times that provide unlimited resources of knowledge and maker tools. I raise the question: In what way does the hybridization of living organisms and non-living technologies affect art audiences in the culture that may be defined as Maker culture? My hypothesis is that active participation of an audience in an artwork is inevitable for experiencing the artwork itself, while also suggesting that the impact of the umwelt changes the perception of an artwork. I emphasize artistic projects that unfold through mutual interaction among diverse peers, including humans, non-human organisms, and machines. In my thesis, I pursue collaborative scenarios that lead to the realization of artistic ideas: (1) the development of ideas by others influenced by me and (2) the materialization of my own ideas influenced by others. By developing the scenarios of collaborative work as an artistic experience, I conclude that the role of an artist in Maker culture is to mediate different types of knowledge and different positions, whereas the role of the audience is to actively engage in the artwork itself. At the same time, aesthetics as experience is triggered by the other, including living and non-living actors. It is intended that the developed methodologies could be further adapted in artistic practices, philosophy, anthropology, and environmental studies.},
  subject      = {Medienkunst},
  language  = {en}
}
@phdthesis{Torreiter,
  author    = {Torreiter, Laura},
  title     = {St{\"a}dtebauliche Aufwertung im Leipziger Osten: Migrant:innen als Pioniere beim Erwerb und der Sanierung von Baudenkmalen},
  doi       = {10.25643/bauhaus-universitaet.6408},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230717-64081},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {209},
  abstract  = {Anhand der st{\"a}dtebaulichen und sozialen Transformation des {\"o}stlichen Gr{\"u}nderzeitgebietes von Leipzig wird die Rolle von migrantischen Hausbesitzenden und in der Bausanierung T{\"a}tigen im Aufwertungsprozess untersucht. Der Zugang zum Gegenstand verbindet Fragen der Stadtsoziologie und der Denkmalforschung. Im sozialen Feld der Stadterneuerung wird die Revitalisierung des ehemals von Leerstand und R{\"u}ckbau betroffenen Baubestandes ausgehandelt. Die Positionen der Akteur:innen im Feld werden durch ihre Ausstattung mit {\"o}konomischem, aber auch sozialem und kulturellem Kapital bestimmt. Angeh{\"o}rige der Planungs- und Denkmalbeh{\"o}rden verf{\"u}gen {\"u}ber institutionalisiertes Kulturkapital und stehen damit Kleineigent{\"u}mer:innen, h{\"a}ufig Autodidakt:innen, gegen{\"u}ber. Baudenkmale k{\"o}nnen {\"u}ber ihre Funktion als Geldanlage und Wohnraum hinaus Status repr{\"a}sentieren und symbolisch angeeignet werden. Denkmalschutz dient dem {\"o}ffentlichen Interesse am Erhalt historischer Bausubstanz. Bei Sanierungen bestehen die Herausforderungen der Vereinbarkeit von Konservierung und Modernisierung, der Finanzierbarkeit f{\"u}r Eigent{\"u}mer:innen und der Sozialvertr{\"a}glichkeit f{\"u}r Bewohnende. Eine Darstellung der historischen Entwicklung des Leipziger Ostens zu Beginn der Analyse veranschaulicht die Abh{\"a}ngigkeit kultureller, sozialer und {\"o}konomischer Werte des Baubestandes vom jeweiligen gesellschaftlichen Kontext. Planerische Konzepte f{\"u}r das Gebiet zeigen, dass eine sozio{\"o}konomische Stabilisierung und Imageverbesserung erreicht werden sollte durch das Aufgreifen von Potentialen, wie den denkmalgesch{\"u}tzten Bauten, dem zuziehenden alternativen Milieu und migrantischer {\"O}konomie. Es wird deutlich, dass nach einer initialen Ans{\"a}ssigkeit von Pionier:innen die {\"o}ffentlichen Infrastrukturmaßnahmen und Denkmalausweisungen eine Inwertsetzung v. a. durch externe Anlegende vorbereiteten. Darauf aufbauend wurden anhand einer qualitativen Befragung die Erfahrungen von st{\"a}dtischen Mitarbeitenden, Fachleuten und im Quartier Engagierten denen von lokalen migrantischen Hausbesitzenden und im Bereich Sanierung T{\"a}tigen gegen{\"u}bergestellt. Migrant:innengruppen haben den Stadtraum in einer Phase vorherrschender Abwanderung durch die Er{\"o}ffnung von Gesch{\"a}ften und Institutionen sowie den Erwerb von Immobilien f{\"u}r sich erschlossen. Strukturelle Benachteiligungen, wie Diskriminierung auf dem Arbeitsmarkt, ihre Ans{\"a}ssigkeit im sozial stigmatisierten Gebiet sowie geringes {\"o}konomisches Kapital versuchten sie durch den Einsatz von sozialem Kapital auszugleichen. Sanierungen erfolgten mit hoher Eigenleistung und R{\"u}ckgriff auf private Netzwerke. Die Analyse des Erneuerungsprozesses im Leipziger Osten zeigt, dass in einer initialen Phase Pionier:innen von Planenden und der Denkmalpflege als essentiell f{\"u}r die Entwicklung angesehen wurden. G{\"u}nstige Instandsetzungen durch Kleineigent{\"u}mer:innen wurden akzeptiert, um Geb{\"a}ude vor weiterem Verfall zu bewahren. Mit der zunehmenden Forderung nach Verwendung hochwertiger Materialen werden die Sanierungsleistungen nach {\"a}sthetischen und letztlich {\"o}konomischen Kriterien bewertet. Gegen{\"u}ber sozialen Folgen einer Aufwertung von Bausubstanz l{\"a}sst sich eine unkritische Haltung der Denkmalpflege erkennen. Bei der Vermarktung der Best{\"a}nde durch professionelle Investierende findet die Sozialgeschichte des Stadtteils wenig Ber{\"u}cksichtigung, positiv besetzte Merkmale des Quartiers, wie Multikulturalit{\"a}t werden selektiv aufgegriffen. Der Anteil migrantischer Akteur:innen an der Entwicklung wird durch die {\"O}ffentlichkeit unzureichend anerkannt. Auch die Wertsch{\"a}tzung von Planenden und im Quartier Engagierten erfolgt v. a. anhand des {\"o}konomischen Status. Hohe Erwartungen an die Gesch{\"a}ftsstruktur und die Erscheinung des Straßenbildes k{\"o}nnen nicht erf{\"u}llt werden. Migrantische Hausbesitzende und im Bereich Sanierung T{\"a}tige ben{\"o}tigen f{\"u}r die Auseinandersetzung mit der Denkmalpflege kulturelles Kapital. Sie erkennen die Bedeutung des historischen Baubestandes f{\"u}r die Stadt und die Arbeit der Institution an, kritisieren jedoch Sanierungsauflagen bzw. Mitarbeitende der Denkmalpflege und k{\"o}nnen sich z. T. gegen diese behaupten. Lokale migrantische Kleineigent{\"u}mer:innen leisten durch ihre Quartiersbindung einen Beitrag zur {\"o}konomischen und sozialen Stabilisierung. Mit ihrer Aufstiegsorientierung f{\"o}rdern sie in der Vermietungspraxis jedoch nur bedingt die Integration anderer Migrant:innen und grenzen sich von statusniedrigen Gruppen im Quartier ab. Migrantische Hausbesitzende und Unternehmende nehmen sich selbst als erfolgreiche Vorreitende in einer heterogener werdenden ostdeutschen Stadtgesellschaft wahr. Sie erkannten fr{\"u}hzeitig das Entwicklungspotential und geh{\"o}ren zu den Initiierenden und Profitierenden der Inwertsetzung.},
  subject      = {Leipzig},
  language  = {de}
}
@phdthesis{Ajjour,
  author    = {Ajjour, Yamen},
  title     = {Addressing Controversial Topics in Search Engines},
  doi       = {10.25643/bauhaus-universitaet.6403},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230626-64037},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {133},
  abstract  = {Search engines are very good at answering queries that look for facts. Still, information needs that concern forming opinions on a controversial topic or making a decision remain a challenge for search engines. Since they are optimized to retrieve satisfying answers, search engines might emphasize a specific stance on a controversial topic in their ranking, amplifying bias in society in an undesired way. Argument retrieval systems support users in forming opinions about controversial topics by retrieving arguments for a given query. In this thesis, we address challenges in argument retrieval systems that concern integrating them in search engines, developing generalizable argument mining approaches, and enabling frame-guided delivery of arguments. Adapting argument retrieval systems to search engines should start by identifying and analyzing information needs that look for arguments. To identify questions that look for arguments we develop a two-step annotation scheme that first identifies whether the context of a question is controversial, and if so, assigns it one of several question types: factual, method, and argumentative. Using this annotation scheme, we create a question dataset from the logs of a major search engine and use it to analyze the characteristics of argumentative questions. The analysis shows that the proportion of argumentative questions on controversial topics is substantial and that they mainly ask for reasons and predictions. The dataset is further used to develop a classifier to uniquely map questions to the question types, reaching a convincing F1-score of 0.78. While the web offers an invaluable source of argumentative content to respond to argumentative questions, it is characterized by multiple genres (e.g., news articles and social fora). Exploiting the web as a source of arguments relies on developing argument mining approaches that generalize over genre. To this end, we approach the problem of how to extract argument units in a genre-robust way. Our experiments on argument unit segmentation show that transfer across genres is rather hard to achieve using existing sequence-to-sequence models. Another property of text which argument mining approaches should generalize over is topic. Since new topics appear daily on which argument mining approaches are not trained, argument mining approaches should be developed in a topic-generalizable way. Towards this goal, we analyze the coverage of 31 argument corpora across topics using three topic ontologies. The analysis shows that the topics covered by existing argument corpora are biased toward a small subset of easily accessible controversial topics, hinting at the inability of existing approaches to generalize across topics. In addition to corpus construction standards, fostering topic generalizability requires a careful formulation of argument mining tasks. Same side stance classification is a reformulation of stance classification that makes it less dependent on the topic. First experiments on this task show promising results in generalizing across topics. To be effective at persuading their audience, users of an argument retrieval system should select arguments from the retrieved results based on what frame they emphasize of a controversial topic. An open challenge is to develop an approach to identify the frames of an argument. To this end, we define a frame as a subset of arguments that share an aspect. We operationalize this model via an approach that identifies and removes the topic of arguments before clustering them into frames. We evaluate the approach on a dataset that covers 12,326 frames and show that identifying the topic of an argument and removing it helps to identify its frames.},
  subject      = {Informatik},
  language  = {en}
}
@phdthesis{Ashour,
  author    = {Ashour, Mohammed},
  title     = {Electromechanics and Hydrodynamics of Single Vesicles and Vesicle Doublet Using Phase-Field Isogeometric Analysis},
  doi       = {10.25643/bauhaus-universitaet.6400},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230628-64003},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {175},
  abstract  = {Biomembranes are selectively permeable barriers that separate the internal components of the cell from its surroundings. They have remarkable mechanical behavior which is characterized by many phenomena, but most noticeably their fluid-like in-plane behavior and solid-like out-of-plane behavior. Vesicles have been studied in the context of discrete models, such as Molecular Dynamics, Monte Carlo methods, Dissipative Particle Dynamics, and Brownian Dynamics. Those methods, however, tend to have high computational costs, which limited their uses for studying atomistic details. In order to broaden the scope of this research, we resort to the continuum models, where the atomistic details of the vesicles are neglected, and the focus shifts to the overall morphological evolution. Under the umbrella of continuum models, vesicles morphology has been studied extensively. However, most of those studies were limited to the mechanical response of vesicles by considering only the bending energy and aiming for the solution by minimizing the total energy of the system. Most of the literature is divided between two geometrical representation methods; the sharp interface methods and the diffusive interface methods. Both of those methods track the boundaries and interfaces implicitly. In this research, we focus our attention on solving two non-trivial problems. In the first one, we study a constrained Willmore problem coupled with an electrical field, and in the second one, we investigate the hydrodynamics of a vesicle doublet suspended in an external viscous fluid flow. For the first problem, we solve a constrained Willmore problem coupled with an electrical field using isogeometric analysis to study the morphological evolution of vesicles subjected to static electrical fields. The model comprises two phases, the lipid bilayer, and the electrolyte. This two-phase problem is modeled using the phase-field method, which is a subclass of the diffusive interface methods mentioned earlier. The bending, flexoelectric, and dielectric energies of the model are reformulated using the phase-field parameter. A modified Augmented-Lagrangian (ALM) approach was used to satisfy the constraints while maintaining numerical stability and a relatively large time step. This approach guarantees the satisfaction of the constraints at each time step over the entire temporal domain. In the second problem, we study the hydrodynamics of vesicle doublet suspended in an external viscous fluid flow. Vesicles in this part of the research are also modeled using the phase-field model. The bending energy and energies associated with enforcing the global volume and area are considered. In addition, the local inextensibility condition is ensured by introducing an additional equation to the system. To prevent the vesicles from numerically overlapping, we deploy an interaction energy definition to maintain a short-range repulsion between the vesicles. The fluid flow is modeled using the incompressible Navier-Stokes equations and the vesicle evolution in time is modeled using two advection equations describing the process of advecting each vesicle by the fluid flow. To overcome the velocity-pressure saddle point system, we apply the Residual-Based Variational MultiScale (RBVMS) method to the Navier-Stokes equations and solve the coupled systems using isogeometric analysis. We study vesicle doublet hydrodynamics in shear flow, planar extensional flow, and parabolic flow under various configurations and boundary conditions. The results reveal several interesting points about the electrodynamics and hydrodynamics responses of single vesicles and vesicle doublets. But first, it can be seen that isogeometric analysis as a numerical tool has the ability to model and solve 4th-order PDEs in a primal variational framework at extreme efficiency and accuracy due to the abilities embedded within the NURBS functions without the need to reduce the order of the PDE by creating an intermediate environment. Refinement whether by knot insertion, order increasing or both is far easier to obtain than traditional mesh-based methods. Given the wide variety of phenomena in natural sciences and engineering that are mathematically modeled by high-order PDEs, the isogeometric analysis is among the most robust methods to address such problems as the basis functions can easily attain high global continuity. On the applicational side, we study the vesicle morphological evolution based on the electromechanical liquid-crystal model in 3D settings. This model describing the evolution of vesicles is composed of time-dependent, highly nonlinear, high-order PDEs, which are nontrivial to solve. Solving this problem requires robust numerical methods, such as isogeometric analysis. We concluded that the vesicle tends to deform under increasing magnitudes of electric fields from the original sphere shape to an oblate-like shape. This evolution is affected by many factors and requires fine-tuning of several parameters, mainly the regularization parameter which controls the thickness of the diffusive interface width. But it is most affected by the method used for enforcing the constraints. The penalty method in presence of an electrical field tends to lock on the initial phase-field and prevent any evolution while a modified version of the ALM has proven to be sufficiently stable and accurate to let the phase-field evolve while satisfying the constraints over time at each time step. We show additionally the effect of including the flexoelectric nature of the Biomembranes in the computation and how it affects the shape evolution as well as the effect of having different conductivity ratios. All the examples were solved based on a staggered scheme, which reduces the computational cost significantly. For the second part of the research, we consider vesicle doublet suspended in a shear flow, in a planar extensional flow, and in a parabolic flow. When the vesicle doublet is suspended in a shear flow, it can either slip past each other or slide on top of each other based on the value of the vertical displacement, that is the vertical distance between the center of masses between the two vesicles, and the velocity profile applied. When the vesicle doublet is suspended in a planar extensional flow in a configuration that resembles a junction, the time in which both vesicles separate depends largely on the value of the vertical displacement after displacing as much fluid from between the two vesicles. However, when the vesicles are suspended in a tubular channel with a parabolic fluid flow, they develop a parachute-like shape upon converging towards each other before exiting the computational domain from the predetermined outlets. This shape however is affected largely by the height of the tubular channel in which the vesicle is suspended. The velocity essential boundary conditions are imposed weakly and strongly. The weak implementation of the boundary conditions was used when the velocity profile was defined on the entire boundary, while the strong implementation was used when the velocity profile was defined on a part of the boundary. The strong implementation of the essential boundary conditions was done by selectively applying it to the predetermined set of elements in a parallel-based code. This allowed us to simulate vesicle hydrodynamics in a computational domain with multiple inlets and outlets. We also investigate the hydrodynamics of oblate-like shape vesicles in a parabolic flow. This work has been done in 2D configuration because of the immense computational load resulting from a large number of degrees of freedom, but we are actively seeking to expand it to 3D settings and test a broader set of parameters and geometrical configurations.},
  subject      = {Isogeometrische Analyse},
  language  = {en}
}
@phdthesis{Mthunzi,
  author    = {Mthunzi, Everett},
  title     = {Interactive Surface Environments: Design and Implementation},
  doi       = {10.25643/bauhaus-universitaet.6406},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230704-64065},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {128},
  abstract  = {This dissertation presents three studies on the design and implementation of interactive surface environments. It puts forward approaches to engineering interactive surface prototypes using prevailing methodologies and technologies. The scholarly findings from each study have been condensed into academic manuscripts, which are conferred herewith. The first study identifies a communication gap between engineers of interactive surface systems (i.e., originators of concepts) and future developers. To bridge the gap, it explores a UML-based framework to establish a formal syntax for modeling hardware, middleware, and software of interactive surface prototypes. The proposed framework targets models-as-end-products, towards enabling a shared view of research prototypes thereby facilitating dialogue between concept originators and future developers. The second study positions itself to support developers with an open-source solution for exploiting 3D point clouds for interactive tabletop applications using CPU architectures. Given dense 3D point-cloud representations of tabletop environments, the study aims toward mitigating high computational effort by segmenting candidate interaction regions as a preprocessing step. The study contributes a robust open-source solution for reducing computational costs when leveraging 3D point clouds for interactive tabletop applications. The solution itself is flexible and adaptable to variable interactive surface applications. The third study contributes an archetypal concept for integrating mobile devices as active components in augmented tabletop surfaces. With emphasis on transparent development trails, the study demonstrates the utility of the open-source tool developed in the second study. In addition to leveraging 3D point clouds for real-time interaction, the research considers recent advances in computer vision and wireless communication to realize a modern, interactive tabletop application. A robust strategy that combines spatial augmented reality, point-cloud-based depth perception, CNN-based object detection, and Bluetooth communication is put forward. In addition to seamless communication between adhoc mobile devices and interactive tabletop systems, the archetypal concept demonstrates the benefits of preprocessing point clouds by segmenting candidate interaction regions, as suggested in the second study. Collectively, the studies presented in this dissertation contribute; 1—bridging the gap between originators of interactive surface concepts and future developers, 2— promoting the exploration of 3D point clouds for interactive surface applications using CPU-based architectures, and 3—leveraging 3D point clouds together with emerging CNN-based object detection, and Bluetooth communication technologies to advance existing surface interaction concepts.},
  subject      = {Mensch-Maschiene-Kommunikation},
  language  = {en}
}
@phdthesis{Dokhanchi,
  author    = {Dokhanchi, Najmeh Sadat},
  title     = {Measurement of the Indoor Air Temperature Distribution using Acoustic Travel-Time Tomography},
  isbn      = {978-3-00-075344-2 (print)},
  doi       = {10.25643/bauhaus-universitaet.4956},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230414-49567},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {155},
  abstract  = {One of the main criteria determining the thermal comfort of occupants is the air temperature. To monitor this parameter, a thermostat is traditionally mounted in the indoor environment for instance in office rooms in the workplaces, or directly on the radiator or in another location in a room. One of the drawbacks of this conventional method is the measurement at a certain location instead of the temperature distribution in the entire room including the occupant zone. As a result, the climatic conditions measured at the thermostat point may differ from those at the user's location. This not only negatively impacts the thermal comfort assessment but also leads to a waste of energy due to unnecessary heating and cooling. Moreover, for measuring the distribution of the air temperature under laboratory conditions, multiple thermal sensors should be installed in the area under investigation. This requires high effort in both installation and expense. To overcome the shortcomings of traditional sensors, Acoustic travel-time TOMography (ATOM) offers an alternative based on measuring the transmission sound velocity signals. The basis of the ATOM technique is the first-order dependency of the sound velocity on the medium's temperature. The average sound velocity, along the propagation paths, can be determined by travel-times estimation of a defined acoustic signal between transducers. After the travel-times collection, the room is divided into several volumetric grid cells, i.e. voxels, whose sizes are defined depending on the dimension of the room and the number of sound paths. Accordingly, the spatial air temperature in each voxel can be determined using a suitable tomographic algorithm. Recent studies indicate that despite the great potential of this technique to detect room climate, few experiments have been conducted. This thesis aims to develop the ATOM technique for indoor climatic applications while coupling the analysis methods of tomography and room acoustics. The method developed in this thesis uses high-energy early reflections in addition to the direct paths between transducers for travel time estimation. In this way, reflections can provide multiple sound paths that allow the room coverage to be maintained even when a few or even only one transmitter and receiver are used. In the development of the ATOM measurement system, several approaches have been employed, including the development of numerical methods and simulations and conducting experimental measurements, each of which has contributed to the improvement of the system's accuracy. In order to effectively separate the early reflections and ensure adequate coverage of the room with sound paths, a numerical method was developed based on the optimization of the coordinates of the sound transducers in the test room. The validation of the optimal positioning method shows that the reconstructed temperatures were significantly improved by placing the transducers at the optimal coordinates derived from the developed numerical method. The other numerical method developed is related to the selection of the travel times of the early reflections. Accordingly, the detection of the travel times has been improved by adjusting the lengths of the multiple analysis time-windows according to the individual travel times in the reflectogram of the room impulse response. This can reduce the probability of trapping faulty travel times in the analysis time-windows. The simulation model used in this thesis is based on the image source model (ISM) method for simulating the theoretical travel times of early reflection sound paths. The simulation model was developed to simulate the theoretical travel times up to third-order reflections. The empirical measurements were carried out in the climate lab of the Chair of Building Physics under different boundary conditions, i.e., combinations of different room air temperatures under both steady-state and transient conditions, and different measurement setups. With the measurements under controllable conditions in the climate lab, the validity of the developed numerical methods was confirmed. In this thesis, the performance of the ATOM measurement system was evaluated using two measurement setups. The setup for the initial investigations consists of an omnidirectional receiver and a near omnidirectional sound source, keeping the number of transducers as few as possible. This has led to accurately identify the sources of error that could occur in each part of the measuring system. The second measurement setup consists of two directional sound sources and one omnidirectional receiver. This arrangement of transducers allowed a higher number of well-detected travel times for tomography reconstruction, a better travel time estimation due to the directivity of the sound source, and better space utilization. Furthermore, this new measurement setup was tested to determine an optimal selection of the excitation signal. The results showed that for the utilized setup, a linear chirp signal with a frequency range of 200 - 4000 Hz and a signal duration of t = 1 s represents an optimal selection with respect to the reliability of the measured travel times and higher signal-to-noise ratio (SNR). To evaluate the performance of the measuring setups, the ATOM temperatures were always compared with the temperatures of high-resolution NTC thermistors with an accuracy of ±0.2 K. The entire measurement program, including acoustic measurements, simulation, signal processing, and visualization of measurement results are performed in MATLAB software. In addition, to reduce the uncertainty of the positioning of the transducers, the acoustic centre of the loudspeaker was determined experimentally for three types of excitation signals, namely MLS (maximum length sequence) signals with different lengths and duration, linear and logarithmic chirp signals with different defined frequency ranges. For this purpose, the climate lab was converted into a fully anechoic chamber by attaching absorption panels to the entire surfaces of the room. The measurement results indicated that the measurement of the acoustic centre of the sound source significantly reduces the displacement error of the transducer position. Moreover, to measure the air temperature in an occupied room, an algorithm was developed that can convert distorted signals into pure reference signals using an adaptive filter. The measurement results confirm the validity of the approach for a temperature interval of 4 K inside the climate lab. Accordingly, the accuracy of the reconstructed temperatures indicated that ATOM is very suitable for measuring the air temperature distribution in rooms.},
  subject      = {Bauphysik},
  language  = {en}
}