@misc{Pessoa, type = {Master Thesis}, author = {Pessoa, Suelen}, title = {Why do the Archives archive? A journey from the hunko to the counter-ethnography and back}, doi = {10.25643/bauhaus-universitaet.4328}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210112-43280}, school = {Bauhaus-Universit{\"a}t Weimar}, abstract = {A complex artistic research on the theme of cultural heritage and (neo)colonial processes of material and immaterial expropriation. Starting from the encounter with a phonographic relic at the Berliner Phonogramm-Archiv, the artist embarks on a journey to her own roots embodied in the practice of the Afro-Brazilian religion Candombl{\´e}. In the form of a theoretical treatise, an archive (photos, diagrams, maps, newspaper clippings, letters, documents), as well as a sound performance in the public space of the city of Weimar, several theoretical and performative elements are brought together in this transmedia artistic research that proposes a true decolonial practice.}, subject = {K{\"u}nstlerische Forschung}, language = {en} } @misc{Ansari, type = {Master Thesis}, author = {Ansari, Meisam}, title = {Simulation methods for functional and microstructured composite materials}, doi = {10.25643/bauhaus-universitaet.4278}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20201103-42783}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {110}, abstract = {In this thesis, a generic model for the post-failure behavior of concrete in tension is proposed. A mesoscale model of concrete representing the heterogeneous nature of concrete is formulated. The mesoscale model is composed of three phases: aggregate, mortar matrix, and the Interfacial Transition Zone between them. Both local and non-local formulations of the damage are implemented and the results are compared. Three homogenization schemes from the literature are employed to obtain the homogenized constitutive relationship for the macroscale model. Three groups of numerical examples are provided.}, subject = {Simulation}, language = {en} } @misc{MacielCostadaSilva, type = {Master Thesis}, author = {Maciel Costa da Silva, Luiza}, title = {Smart Cities and Mobility Stations: Lessons learned from the Smarter Together in Vienna and Munich}, doi = {10.25643/bauhaus-universitaet.4270}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20201012-42702}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {110}, abstract = {With an increasing urban population and urban problems arising from this unplanned growth, several projects aimed at promoting sustainable urban development have emerged. Smart mobility strategies, such as shared mobility and mobility stations, represent some of the solutions to promote changes in travel behavior. Despite its beneficial impacts, however, the implementation of such infrastructure is criticized for not contributing to current urban issues, as well as often disregarding knowledge about urban space and its functioning. In this context, the Smarter Together, a joint research and innovation project funded through the European Union program H2020, was implemented. The project selected three lighthouse cities to test and upscale innovative solutions: Vienna, Munich, and Lyon. This master thesis presents the main characteristics of the mobility stations systems implemented in Vienna and Munich in the scope of the project Smarter Together. Its main goal is to share what can be learned from their experiences while approaching critically the concept of smart cities. This master thesis identifies important aspects to take into account when planning, implementing, and operating mobility stations, and provides an understanding of smart cities and smart mobility that goes beyond the adoption of technology. Several methods were combined for the development of this master thesis, such as quantitative secondary data, observational studies, application of survey forms, explorative expert interviews, and literature review. This work has demonstrated that the Smarter Together has a cutting-edge scope and contributed greatly to research and innovation, by creating living laboratories to test the application of technology in the urban environment. However, from the perspective of the mobility stations assessment, many caveats were made. In short, many lessons could be learned and are presented throughout this work aiming at contributing to the improvement of the mobility stations implemented in the project areas in Munich and Vienna, as well as for inspiring other cities in Europe and worldwide.}, subject = {Intelligente Stadt}, language = {en} } @misc{MendoncadeAlmeida, type = {Master Thesis}, author = {Mendon{\c{c}}a de Almeida, Karina}, title = {Why isn't Google welcome in Kreuzberg? Social movement and the effects of Internet on urban space}, doi = {10.25643/bauhaus-universitaet.4244}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200924-42446}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {132}, abstract = {Advances in information and communication technologies such as the Internet have driven a great transformation in the interactions between individuals and the urban environment. As the use of the Internet in cities becomes more intense and diverse, there is also a restructuring of urban space, which is experienced by groups in society in various ways, according to the specificity of each context. Accordingly, large Internet companies have emerged as new players in the processes of urbanization, either through partnerships with the public administration or through various services offered directly to urban residents. Once these corporations are key actors in the digitalization of urban services, their operations can affect the patterns of urban inequality and generate a series of new struggles over the production of space. Interested in analyzing this phenomena from the perspective of civil society, the present Master Thesis examined a social movement that prevented Google to settle a new startup campus in the district of Kreuzberg, in Berlin. By asking why Google was not welcome in that context, this study also sought to understand how internet, as well as its main operators, has affected everyday life in the city. Thus, besides analyzing the movement, I investigated the particularities of the urban context where it arose and the elements that distinguish the mobilization's opponent. In pursuit of an interdisciplinary approach, I analyzed and discussed the results of empirical research in dialogue with critical theories in the fields of urban studies and the Internet, with emphasis on Castells' definitions of urban social movements and network society (1983, 2009, 2015), Couldry's and Mejias' (2019) idea of data colonialism, Lef{\`e}bvre's (1991, 1996) concepts of abstract space and the right to the city, as well as Zuboff's (2019) theory of surveillance capitalism. The case at hand has exposed that Google plays a prominent role in the way the Internet has been developed and deployed in cities. From the perspective accessed, the current appropriation of Internet technologies has been detrimental to individual autonomy and has contributed to intensifying existing inequalities in the city. The alternative vision to this relies mainly on the promotion of decentralized solidarity networks.}, subject = {Soziale Bewegung}, language = {en} } @misc{Froehlich, type = {Master Thesis}, author = {Fr{\"o}hlich, Jan}, title = {On systematic approaches for interpreted information transfer of inspection data from bridge models to structural analysis}, doi = {10.25643/bauhaus-universitaet.4131}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200416-41310}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {82}, abstract = {In conjunction with the improved methods of monitoring damage and degradation processes, the interest in reliability assessment of reinforced concrete bridges is increasing in recent years. Automated imagebased inspections of the structural surface provide valuable data to extract quantitative information about deteriorations, such as crack patterns. However, the knowledge gain results from processing this information in a structural context, i.e. relating the damage artifacts to building components. This way, transformation to structural analysis is enabled. This approach sets two further requirements: availability of structural bridge information and a standardized storage for interoperability with subsequent analysis tools. Since the involved large datasets are only efficiently processed in an automated manner, the implementation of the complete workflow from damage and building data to structural analysis is targeted in this work. First, domain concepts are derived from the back-end tasks: structural analysis, damage modeling, and life-cycle assessment. The common interoperability format, the Industry Foundation Class (IFC), and processes in these domains are further assessed. The need for usercontrolled interpretation steps is identified and the developed prototype thus allows interaction at subsequent model stages. The latter has the advantage that interpretation steps can be individually separated into either a structural analysis or a damage information model or a combination of both. This approach to damage information processing from the perspective of structural analysis is then validated in different case studies.}, subject = {Br{\"u}ckenbau}, language = {en} } @misc{Hamzah, type = {Master Thesis}, author = {Hamzah, Abdulrazzak}, title = {L{\"o}sung von Randwertaufgaben der Bruchmechanik mit Hilfe einer approximationsbasierten Kopplung zwischen der Finite-Elemente-Methode und Methoden der komplexen Analysis}, doi = {10.25643/bauhaus-universitaet.4093}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200211-40936}, school = {Bauhaus-Universit{\"a}t Weimar}, abstract = {Das Hauptziel der vorliegenden Arbeit war es, eine stetige Kopplung zwischen der ananlytischen und numerischen L{\"o}sung von Randwertaufgaben mit Singularit{\"a}ten zu realisieren. Durch die inter-polationsbasierte gekoppelte Methode kann eine globale C0 Stetigkeit erzielt werden. F{\"u}r diesen Zweck wird ein spezielle finite Element (Kopplungselement) verwendet, das die Stetigkeit der L{\"o}sung sowohl mit dem analytischen Element als auch mit den normalen CST Elementen gew{\"a}hrleistet. Die interpolationsbasierte gekoppelte Methode ist zwar f{\"u}r beliebige Knotenanzahl auf dem Interface ΓAD anwendbar, aber es konnte durch die Untersuchung von der Interpolationsmatrix und numerische Simulationen festgestellt werden, dass sie schlecht konditioniert ist. Um das Problem mit den numerischen Instabilit{\"a}ten zu bew{\"a}ltigen, wurde eine approximationsbasierte Kopplungsmethode entwickelt und untersucht. Die Stabilit{\"a}t dieser Methode wurde anschließend anhand der Untersuchung von der Gramschen Matrix des verwendeten Basissystems auf zwei Intervallen [-π,π] und [-2π,2π] beurteilt. Die Gramsche Matrix auf dem Intervall [-2π,2π] hat einen g{\"u}nstigeren Konditionszahl in der Abh{\"a}ngigkeit von der Anzahl der Kopplungsknoten auf dem Interface aufgewiesen. Um die dazu geh{\"o}rigen numerischen Instabilit{\"a}ten ausschließen zu k{\"o}nnen wird das Basissystem mit Hilfe vom Gram-Schmidtschen Orthogonalisierungsverfahren auf beiden Intervallen orthogonalisiert. Das orthogonale Basissystem l{\"a}sst sich auf dem Intervall [-2π,2π] mit expliziten Formeln schreiben. Die Methode des konsistentes Sampling, die h{\"a}ufig in der Nachrichtentechnik verwendet wird, wurde zur Realisierung von der approximationsbasierten Kopplung herangezogen. Eine Beschr{\"a}nkung dieser Methode ist es, dass die Anzahl der Sampling-Basisfunktionen muss gleich der Anzahl der Wiederherstellungsbasisfunktionen sein. Das hat dazu gef{\"u}hrt, dass das eingef{\"u}hrt Basissys-tem (mit 2 n Basisfunktionen) nur mit n Basisfunktion verwendet werden kann. Zur L{\"o}sung diese Problems wurde ein alternatives Basissystems (Variante 2) vorgestellt. F{\"u}r die Verwendung dieses Basissystems ist aber eine Transformationsmatrix M n{\"o}tig und bei der Orthogonalisierung des Basissystems auf dem Intervall [-π,π] kann die Herleitung von dieser Matrix kompliziert und aufwendig sein. Die Formfunktionen wurden anschließend f{\"u}r die beiden Varianten hergeleitet und grafisch (f{\"u}r n = 5) dargestellt und wurde gezeigt, dass diese Funktionen die Anforderungen an den Formfunktionen erf{\"u}llen und k{\"o}nnen somit f{\"u}r die FE- Approximation verwendet werden. Anhand numerischer Simulationen, die mit der Variante 1 (mit Orthogonalisierung auf dem Intervall [-2π,2π]) durchgef{\"u}hrt wurden, wurden die grundlegenden Fragen (Beispielsweise: Stetigkeit der Verformungen auf dem Interface ΓAD, Spannungen auf dem analytischen Gebiet) {\"u}ber- pr{\"u}ft.}, subject = {Mathematik}, language = {de} } @misc{Duering, type = {Master Thesis}, author = {D{\"u}ring, Serjoscha}, title = {Between plan and reality: tracing the development dynamics of the Lanzhou New Area - a computational approach}, doi = {10.25643/bauhaus-universitaet.4000}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20191108-40002}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {78}, abstract = {Contemporary planning practice is often criticized as too design-driven with a lack of both quantitative evaluation criteria and employment of models that anticipate the self-organizational forces shaping cities, resulting in significant gaps between plan and reality. This study aims to introduce a modular toolbox prototype for spatial-analysis in data-poor environments. It is proposed to integrate designing, evaluation, and monitoring of urban development into one framework, thus supporting data-driven, on-demand urban design, and planning processes. The proposed framework's value will exemplarily be tested, focussing on the analysis and simulation of spatiotemporal growth trajectories taking the Lanzhou New Area as a case-study - a large scale new town project that struggles to attract residents and businesses. Conducted analysis suggests that more attention should be given to spatiotemporal development paths to ensure that cities work more efficiently throughout any stage of development. Finally, early hints on general design strategies to achieve this goal are discussed with the assistance of the proposed toolbox.}, subject = {Stadtplanung}, language = {en} } @misc{vonButler, type = {Master Thesis}, author = {von Butler, Natalie}, title = {Scalarization Methods for Multi-Objective Structural Optimization}, doi = {10.25643/bauhaus-universitaet.4010}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20191030-40106}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {178}, abstract = {Scalarization methods are a category of multiobjective optimization (MOO) methods. These methods allow the usage of conventional single objective optimization algorithms, as scalarization methods reformulate the MOO problem into a single objective optimization problem. The scalarization methods analysed within this thesis are the Weighted Sum (WS), the Epsilon-Constraint (EC), and the MinMax (MM) method. After explaining the approach of each method, the WS, EC and MM are applied, a-posteriori, to three different examples: to the Kursawe function; to the ten bar truss, a common benchmark problem in structural optimization; and to the metamodel of an aero engine exit module. The aim is to evaluate and compare the performance of each scalarization method that is examined within this thesis. The evaluation is conducted using performance metrics, such as the hypervolume and the generational distance, as well as using visual comparison. The application to the three examples gives insight into the advantages and disadvantages of each method, and provides further understanding of an adequate application of the methods concerning high dimensional optimization problems.}, subject = {Mehrkriterielle Optimierung}, language = {en} } @misc{Bendalla, type = {Master Thesis}, author = {Bendalla, Abdulmagid Sedig Khalafallah}, title = {Nonlinear Numerical Modelling of Cable Elements in Bridges for Dynamic Analysis}, doi = {10.25643/bauhaus-universitaet.3994}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20191007-39940}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {107}, abstract = {Identifying cable force with vibration-based methods has become widely used in engineering practice due to simplicity of application. The string taut theory provides a simple definition of the relationship between natural frequencies and the tension force of a cable. However, this theory assumes a perfectly flexible non-sagging cable pinned at its ends. These assumptions do not reflect all cases, especially when the cable is short, under low tension forces or the supports are partially flexible. Extradosed bridges, which are distinguished from cable-stayed bridges by their low pylon height, have shorter cables. Therefore the application of the conventional string taut theory to identify cable forces on extradosed bridge cables might be inadequate to identify cable forces. In this work, numerical modelling of an extradosed bridge cable saddled on a circular deviator at pylon is conducted. The model is validated with the catenary analytical solution and its static and dynamic behaviours are studied. The effect of a saddle support is found to positively affect the cable stiffness by geometric means; longer saddle radius increases the cable stiffness by suppressing the deformations near the saddle. Further, accounting the effects of bending stiffness in the numerical model by using beam elements show considerable deviation from models with truss elements (i.e. zero bending stiffness). This deviation is manifested when comparing the static and dynamic properties. This motivates a more thorough study of bending stiffness effects on short cables. Bending stiffness effects are studied using two rods connected with several springs along their length. Under bending moments, the springs resist the rods' relative axial displacement by the springs' transverse component. This concept is used to identify bending stiffness values by utilizing the parallel axis theorem to quantify ratios of the second moment of area. These ratios are calculated based on the setup of the springs (e.g. number of springs per unit length, transverse stiffness, etc...). The numerical model based on this concept agrees well with the theoretical values computed using upper and lower bounds of the parallel axis theorem. The proposed concept of quantifying ratios of the second moment of area using springs as connection between cable rods is applied on an actual extradosed bridge geometry. The model is examined by comparison to the previously validated global numerical model. The two models showed good correlation under various changing parameters. This allowed further study of the effects of stick/slip behaviour between cable rods on an actual bridge geometry.}, subject = {Kabel}, language = {en} } @misc{Zafar, type = {Master Thesis}, author = {Zafar, Usman}, title = {Probabilistic Reliability Analysis of Wind Turbines}, doi = {10.25643/bauhaus-universitaet.3977}, school = {Bauhaus-Universit{\"a}t Weimar}, abstract = {Renewable energy use is on the rise and these alternative resources of energy can help combat with the climate change. Around 80\% of the world's electricity comes from coal and petroleum however, the renewables are the fastest growing source of energy in the world. Solar, wind, hydro, geothermal and biogas are the most common forms of renewable energy. Among them, wind energy is emerging as a reliable and large-scaled source of power production. The recent research and confidence in the performance has led to the construction of more and bigger wind turbines around the world. As wind turbines are getting bigger, a concern regarding their safety is also in discussion. Wind turbines are expensive machinery to construct and the enormous capital investment is one of the main reasons, why many countries are unable to adopt to the wind energy. Generally, a reliable wind turbine will result in better performance and assist in minimizing the cost of operation. If a wind turbine fails, it's a loss of investment and can be harmful for the surrounding habitat. This thesis aims towards estimating the reliability of an offshore wind turbine. A model of Jacket type offshore wind turbine is prepared by using finite element software package ABAQUS and is compared with the structural failure criteria of the wind turbine tower. UQLab, which is a general uncertainty quantification framework developed at ETH Z{\"u}rich, is used for the reliability analysis. Several probabilistic methods are included in the framework of UQLab, which include Monte Carlo, First Order Reliability Analysis and Adaptive Kriging Monte Carlo simulation. This reliability study is performed only for the structural failure of the wind turbine but it can be extended to many other forms of failures e.g. reliability for power production, or reliability for different component failures etc. It's a useful tool that can be utilized to estimate the reliability of future wind turbines, that could result in more safer and better performance of wind turbines.}, subject = {Windturbine}, language = {en} }