@article{AlsaadHartmannVoelker, author = {Alsaad, Hayder and Hartmann, Maria and Voelker, Conrad}, title = {The effect of a living wall system designated for greywater treatment on the hygrothermal performance of the facade}, series = {Energy and Buildings}, volume = {2022}, journal = {Energy and Buildings}, number = {volume 255, article 111711}, doi = {10.1016/j.enbuild.2021.111711}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20240116-65299}, pages = {17}, abstract = {Besides their multiple known benefits regarding urban microclimate, living walls can be used as decentralized stand-alone systems to treat greywater locally at the buildings. While this offers numerous environmental advantages, it can have a considerable impact on the hygrothermal performance of the facade as such systems involve bringing large quantities of water onto the facade. As it is difficult to represent complex entities such as plants in the typical simulation tools used for heat and moisture transport, this study suggests a new approach to tackle this challenge by coupling two tools: ENVI-Met and Delphin. ENVI-Met was used to simulate the impact of the plants to determine the local environmental parameters at the living wall. Delphin, on the other hand, was used to conduct the hygrothermal simulations using the local parameters calculated by ENVI-Met. Four wall constructions were investigated in this study: an uninsulated brick wall, a precast concrete plate, a sandy limestone wall, and a double-shell wall. The results showed that the living wall improved the U-value, the exterior surface temperature, and the heat flux through the wall. Moreover, the living wall did not increase the risk of moisture in the wall during winter and eliminated the risk of condensation.}, subject = {Feuchteleitung}, language = {en} } @article{PollackLueckWolfetal., author = {Pollack, Moritz and L{\"u}ck, Andrea and Wolf, Mario and Kraft, Eckhard and V{\"o}lker, Conrad}, title = {Energy and Business Synergy: Leveraging Biogenic Resources from Agriculture, Waste, and Wastewater in German Rural Areas}, series = {Sustainability}, volume = {2023}, journal = {Sustainability}, number = {volume 15, issue 24, article 16573}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/su152416573}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231222-65172}, pages = {1 -- 25}, abstract = {The imperative to transform current energy provisions is widely acknowledged. However, scant attention has hitherto been directed toward rural municipalities and their innate resources, notably biogenic resources. In this paper, a methodological framework is developed to interconnect resources from waste, wastewater, and agricultural domains for energy utilization. This entails cataloging existing resources, delineating their potential via quantitative assessments utilizing diverse technologies, and encapsulating them in a conceptual model. The formulated models underwent iterative evaluation with engagement from diverse stakeholders. Consequently, 3 main concepts, complemented by 72 sub-concepts, were delineated, all fostering positive contributions to climate protection and providing heat supply in the rural study area. The outcomes' replicability is underscored by the study area's generic structure and the employed methodology. Through these inquiries, a framework for the requisite energy transition, with a pronounced emphasis on the coupling of waste, wastewater, and agriculture sectors in rural environments, is robustly analyzed.}, subject = {Energiewende}, language = {en} } @article{SchwenkeSoebkeKraft, author = {Schwenke, Nicolas and S{\"o}bke, Heinrich and Kraft, Eckhard}, title = {Potentials and Challenges of Chatbot-Supported Thesis Writing: An Autoethnography}, series = {Trends in Higher Education}, volume = {2023}, journal = {Trends in Higher Education}, number = {Volume 2, issue 4}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/higheredu2040037}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231207-65016}, pages = {611 -- 635}, abstract = {The release of the large language model-based chatbot ChatGPT 3.5 in November 2022 has brought considerable attention to the subject of artificial intelligence, not only to the public. From the perspective of higher education, ChatGPT challenges various learning and assessment formats as it significantly reduces the effectiveness of their learning and assessment functionalities. In particular, ChatGPT might be applied to formats that require learners to generate text, such as bachelor theses or student research papers. Accordingly, the research question arises to what extent writing of bachelor theses is still a valid learning and assessment format. Correspondingly, in this exploratory study, the first author was asked to write his bachelor's thesis exploiting ChatGPT. For tracing the impact of ChatGPT methodically, an autoethnographic approach was used. First, all considerations on the potential use of ChatGPT were documented in logs, and second, all ChatGPT chats were logged. Both logs and chat histories were analyzed and are presented along with the recommendations for students regarding the use of ChatGPT suggested by a common framework. In conclusion, ChatGPT is beneficial for thesis writing during various activities, such as brainstorming, structuring, and text revision. However, there are limitations that arise, e.g., in referencing. Thus, ChatGPT requires continuous validation of the outcomes generated and thus fosters learning. Currently, ChatGPT is valued as a beneficial tool in thesis writing. However, writing a conclusive thesis still requires the learner's meaningful engagement. Accordingly, writing a thesis is still a valid learning and assessment format. With further releases of ChatGPT, an increase in capabilities is to be expected, and the research question needs to be reevaluated from time to time.}, subject = {Chatbot}, language = {en} } @article{LizarazuHarirchianShaiketal., author = {Lizarazu, Jorge and Harirchian, Ehsan and Shaik, Umar Arif and Shareef, Mohammed and Antoni-Zdziobek, Annie and Lahmer, Tom}, title = {Application of machine learning-based algorithms to predict the stress-strain curves of additively manufactured mild steel out of its microstructural characteristics}, series = {Results in Engineering}, volume = {2023}, journal = {Results in Engineering}, number = {Volume 20 (2023)}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.rineng.2023.101587}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231207-65028}, pages = {1 -- 12}, abstract = {The study presents a Machine Learning (ML)-based framework designed to forecast the stress-strain relationship of arc-direct energy deposited mild steel. Based on microstructural characteristics previously extracted using microscopy and X-ray diffraction, approximately 1000 new parameter sets are generated by applying the Latin Hypercube Sampling Method (LHSM). For each parameter set, a Representative Volume Element (RVE) is synthetically created via Voronoi Tessellation. Input raw data for ML-based algorithms comprises these parameter sets or RVE-images, while output raw data includes their corresponding stress-strain relationships calculated after a Finite Element (FE) procedure. Input data undergoes preprocessing involving standardization, feature selection, and image resizing. Similarly, the stress-strain curves, initially unsuitable for training traditional ML algorithms, are preprocessed using cubic splines and occasionally Principal Component Analysis (PCA). The later part of the study focuses on employing multiple ML algorithms, utilizing two main models. The first model predicts stress-strain curves based on microstructural parameters, while the second model does so solely from RVE images. The most accurate prediction yields a Root Mean Squared Error of around 5 MPa, approximately 1\% of the yield stress. This outcome suggests that ML models offer precise and efficient methods for characterizing dual-phase steels, establishing a framework for accurate results in material analysis.}, subject = {Maschinelles Lernen}, language = {en} } @article{BertramAltrock, author = {Bertram, Grischa Frederik and Altrock, Uwe}, title = {Jenseits agonistischer Planungstheorien: Die „Normalit{\"a}t"von Protesten und ihr Einfluss auf die Konfliktaustragungin der r{\"a}umlichen Planung}, series = {Raumforschung und Raumordnung}, volume = {2023}, journal = {Raumforschung und Raumordnung}, number = {Vol. 81, No. 5}, publisher = {oekom Verlag}, address = {M{\"u}nchen}, doi = {10.14512/rur.1674}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231207-64995}, pages = {493 -- 508}, abstract = {Die Planungsforschung hat sich sp{\"a}testens seit der „kommunikativen Wende" intensiv damit besch{\"a}ftigt, wie mit Konflikten umgegangen werden soll und wird. Ans{\"a}tze der „agonistischen" Planungstheorie widersprechen der normativen Pr{\"a}misse, Konsensbildung unter den Planungsbeteiligten anzustreben. Vielmehr wollen sie widerstreitende Positionen normativ f{\"u}r die r{\"a}umliche Entwicklung fruchtbar machen. Zugleich betonen sie eine vermeintliche Dualit{\"a}t von Planung und Protest, die in der neueren Protesttheorie infrage gestellt wird. Dieser Beitrag zeigt aufbauend auf einer Diskussion von planungs- und protesttheoretischen Ans{\"a}tzen und einer empirischen Analyse planungsbezogener Proteste in Deutschland, dass diese Proteste von den Planungsakteuren zwar immer st{\"a}rker als „Normalit{\"a}t" aufgefasst werden und antagonistische Partizipation trotz zunehmender Konflikthaftigkeit und vermeintlicher Infragestellung der repr{\"a}sentativen Demokratie kulturell regelgebunden bleibt. Protesthandeln ist Teil ausdifferenzierter „Partizipationsb{\"u}ndel", die situationsbezogen auch Teilnahme an Beteiligungsverfahren, direktdemokratische Verfahren und Klagen umfassen. Protestierende verfolgen dabei meist eine eher reformorientierte Agenda, die keiner „Z{\"a}hmung" bedarf. Allerdings k{\"o}nnen die zugrunde liegenden Konflikte h{\"a}ufig gar nicht „gel{\"o}st" werden. Planenden hingegen k{\"o}nnen auch innerhalb eines agonistischen Planungsumfelds rationalistische und deliberative Ans{\"a}tze zur Verf{\"u}gung stehen, die sie situationsbezogen und strategisch nutzen.}, subject = {Raumplanung}, language = {de} } @article{BrokowLogaKrueger, author = {Brokow-Loga, Anton and Kr{\"u}ger, Timmo}, title = {Potentials of Climate Emergency Declarations for degrowth transformations. The ambivalent stance of German municipalities in conflicts over a post-fossil future}, series = {Raumforschung und Raumordnung}, volume = {2023}, journal = {Raumforschung und Raumordnung}, number = {Vol. 81, No. 5}, publisher = {oekom Verlag}, address = {M{\"u}nchen}, doi = {10.14512/rur.1666}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231204-64984}, pages = {523 -- 537}, abstract = {This paper addresses the scope for action by municipalities in a climate emergency and places it in the framework of ecomodern (urban) policy. We analyse the way in which two German 'climate emergency municipalities' translate conflicts of post-fossil transformation into concrete political and planning strategies. Although more than 2,200 authorities around the world have already declared a climate emergency, research on the impact of these resolutions on the political orientation of municipalities is very limited. Our research focus is on the (potentially agonistic) treatment of conflicts in planning. We argue that in times of a socio-ecological crisis, success in conflict resolution cannot refer to appeasement and depoliticisation. Instead, we propose a framework of five criteria, based on critical theory on ecomodern strategies, planning processes and degrowth. Thus, this practice-related and explorative paper connects empirical insights from the German cities of Constance and Berlin with an innovative normative framework. The findings tell a complex story of an, at least partial, admission of the failure of previous climate mitigation strategies, a lack of social institutions of limits, an instrumental relation to nature and a disregard for social injustices. The paper discusses how municipalities, in the context of ongoing tensions over the post-fossil transformation in Germany, on the one hand hold on to business-as-usual approaches, but on the other hand also set political impulses for change.}, subject = {Stadtentwicklung}, language = {de} } @article{Suhr, author = {Suhr, Maike}, title = {Diversit{\"a}t und (Anti-)Diskriminierung im Kontext journalistischer Neugr{\"u}ndungen: Eine Forschungsagenda}, series = {Global Media Journal German Edition}, volume = {2023}, journal = {Global Media Journal German Edition}, number = {Volume 13, No 1}, doi = {10.22032/dbt.57907}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231027-64836}, pages = {1 -- 19}, abstract = {Obgleich redaktionelle Diversit{\"a}t regelm{\"a}ßig als eine der Kernherausforderungen f{\"u}r den Journalismus gehandelt wird, tun sich journalistische Organisationen immer noch schwer damit, gleichberechtigte Zugangs-und Entfaltungschancen f{\"u}r Frauen, People of Color, Menschen aus Einwandererfamilien oder auf anderen Ebenen diskriminierungsbetroffene Journalist*innen zu schaffen. Stattdessen zeigt die gender-und diversit{\"a}tsbezogene Redaktionsforschung, dass Redaktionen nach wie vor in ihren Strukturen, Praktiken und in ihrer Kultur gesellschaftliche Machtverh{\"a}ltnisse widerspiegeln und (re-)produzieren. Doch im Zuge des „Entrepreneurial Journalism" entstehen heute vielerorts neue Organisationen. Diese journalistischen Neugr{\"u}ndungen zeichnen sich unter anderem durch kleinere, offenere und flexiblere Organisationsstrukturen aus. Ihr ver{\"a}nderter organisationaler Charakter wurde jedoch bislang noch nicht tiefergehend im Hinblick auf seine Potenziale und m{\"o}glichen Risiken f{\"u}r Diversit{\"a}t und (Anti-)Diskriminierung untersucht. Der Beitrag hat somit zum Ziel, journalistische Neugr{\"u}ndungen als neuen Gegenstand auf der Agenda der organisations-und diskriminierungsbezogenen Journalismusforschung zu positionieren. Dazu werden ausgew{\"a}hlte Studien zum „Entrepreneurial Journalism" im Hinblick auf Diversit{\"a}t und (Anti-)Diskriminierung aufgearbeitet und bestehende Desiderata identifiziert. Auf dieser Grundlage wird schließlich eine programmatische Forschungsagenda entwickelt, um empirische Folgeforschung zum Thema anzustoßen.}, subject = {Journalismus}, language = {de} } @article{PartschefeldTutalHalmansederetal., author = {Partschefeld, Stephan and Tutal, Adrian and Halmanseder, Thomas and Schneider, Jens and Osburg, Andrea}, title = {Investigations on Stability of Polycarboxylate Superplasticizers in Alkaline Activators for Geopolymer Binders}, series = {Materials}, volume = {2023}, journal = {Materials}, number = {Volume 16, issue 15, article 5369}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/ma16155369}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20231026-64809}, pages = {1 -- 14}, abstract = {Calcined clays are interesting starting materials to be used as SCMs (supplementary cementitious materials) in cements or to be converted to geopolymers by activation with a high alkaline activator. The adjustment of the properties in the fresh state, especially regarding the consistency of these binders, is almost exclusively achieved by the addition of water, since commercially available superplasticizers seem to be ineffective in low-calcium geopolymer systems. The aim of this study was a systematic investigation of various PCE (polycarboxylate ester/ether) superplasticizers (methacrylate ester PCE: MPEG, isoprenol ether PCE: IPEG, methallyl ether PCE: HPEG) with respect to their stability in different alkaline activators (NaOH, KOH, sodium and potassium silicate solutions). The effectiveness of superplasticizers (SPs) in low-calcium geopolymer binders was verified by rheological tests. Size exclusion chromatography was used to investigate if structural degradation of the superplasticizers occurs. The investigated PCE superplasticizers showed a thickening effect in the low-calcium geopolymer system. Depending on the alkalinity of the activator solution, a degradation process was detected for all the PCEs investigated. The side chains of the PCEs are cleaved off the backbone by basic ester and ether hydrolysis. The highest degree of degradation was found in sodium and potassium silicate solutions. In alkaline hydroxide solutions, the degradation process increases with increasing alkalinity.}, subject = {Geopolymere}, language = {en} } @article{AnsariTartaglioneKoenke, author = {Ansari, Meisam and Tartaglione, Fabiola and K{\"o}nke, Carsten}, title = {Experimental Validation of Dynamic Response of Small-Scale Metaconcrete Beams at Resonance Vibration}, series = {materials}, volume = {2023}, journal = {materials}, number = {volume 16, issue 14, article 5029}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/ma16145029}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230818-64154}, pages = {1 -- 17}, abstract = {Structures and their components experience substantially large vibration amplitudes at resonance, which can cause their failure. The scope of this study is the utilization of silicone-coated steel balls in concrete as damping aggregates to suppress the resonance vibration. The heavy steel cores oscillate with a frequency close to the resonance frequency of the structure. Due to the phase difference between the vibrations of the cores and the structure, the cores counteract the vibration of the structure. The core-coating inclusions are randomly distributed in concrete similar to standard aggregates. This mixture is referred to as metaconcrete. The main goal of this work is to validate the ability of the inclusions to suppress mechanical vibration through laboratory experiments. For this purpose, two small-scale metaconcrete beams were cast and tested. In a free vibration test, the metaconcrete beams exhibited a larger damping ratio compared to a similar beam cast from conventional concrete. The vibration amplitudes of the metaconcrete beams at resonance were measured with a frequency sweep test. In comparison with the conventional concrete beam, both metaconcrete beams demonstrated smaller vibration amplitudes. Both experiments verified an improvement in the dynamic response of the metaconcrete beams at resonance vibration.}, subject = {Beton}, language = {en} } @article{Coenen, author = {Coenen, Ekkehard}, title = {Anti-Gewalttrainings, Gewaltwissen und die institutionelle Erzeugung gewaltbefreiter Subjekte}, series = {Soziale Passagen}, volume = {2023}, journal = {Soziale Passagen}, publisher = {VS, Verl. f{\"u}r Sozialwissenschaften/GWV-Fachverlag}, address = {Wiesbaden}, doi = {10.1007/s12592-023-00453-9}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230720-64104}, pages = {1 -- 16}, abstract = {Dieser Beitrag fragt danach, wie Wissen {\"u}ber Gewalt in Anti-Gewalttrainings produziert, vermittelt und sozial wirkm{\"a}chtig wird. Auf Basis des kommunikativen Konstruktivismus werden diese Kurse als gewaltbezogene Institutionen begriffen, in denen eine Wissensordnung der Gewalt stabilisiert wird. Sie sollen Abweichungen von institutionalisierten Wirklichkeitsvorstellungen in Bezug auf Gewalt entgegenwirken. Dabei lassen sie sich als Selbsttechniken begreifen, durch welche die Kursteilnehmer*innen eine spezifische Subjektposition ein{\"u}ben, n{\"a}mlich die des gewaltbefreiten Subjekts. Vor diesem Hintergrund wird anschließend zwischen konditionalen und konzessiven Anti-Gewalttrainings unterschieden. Erstere wenden sich an Personen, die tats{\"a}chlich von der institutionalisierten Wirklichkeitsvorstellung abgewichen sind und somit gesellschaftlich als Gewaltt{\"a}ter*innen eingestuft werden, w{\"a}hrend Letztere auf eine Klientel zielen, die potenziell von den g{\"a}ngigen Normen abweichen k{\"o}nnte, obwohl noch keine Gewalt aufgetreten sein muss. Abschließend wird gezeigt, dass den Kursleiter*innen eine wichtige Rolle im Subjektivierungsprozess und der Wissenskommunikation {\"u}ber Gewalt zukommt. Neben Wissen {\"u}ber Gewalt werden durch sie auch Wertbindungen, Legitimationen und Weltbilder vermittelt.}, subject = {Gewalt}, language = {de} } @article{VogelArnoldVoelkeretal., author = {Vogel, Albert and Arnold, J{\"o}rg and Voelker, Conrad and Kornadt, Oliver}, title = {Data for sound pressure level prediction in lightweight constructions caused by structure-borne sound sources and their uncertainties}, series = {Data in Brief}, volume = {2023}, journal = {Data in Brief}, number = {Volume 48, June 2023, article 109292}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.dib.2023.109292}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230719-64114}, pages = {1 -- 16}, abstract = {When predicting sound pressure levels induced by structure-borne sound sources and describing the sound propagation path through the building structure as exactly as possible, it is necessary to characterize the vibration behavior of the structure-borne sound sources. In this investigation, the characterization of structure-borne sound sources was performed using the two-stage method (TSM) described in EN 15657. Four different structure-borne sound sources were characterized and subsequently installed in a lightweight test stand. The resulting sound pressure levels in an adjacent receiving room were measured. In the second step, sound pressure levels were predicted according to EN 12354-5 based on the parameters of the structure-borne sound sources. Subsequently, the predicted and the measured sound pressure levels were compared to obtain reliable statements on the achievable accuracy when using source quantities determined by TSM with this prediction method.}, subject = {Bauakustik}, language = {en} } @article{AbdelnourZabel, author = {Abdelnour, Mena and Zabel, Volkmar}, title = {Modal identification of structures with a dynamic behaviour characterised by global and local modes at close frequencies}, series = {Acta Mechanica}, volume = {2023}, journal = {Acta Mechanica}, publisher = {Springer}, address = {Wien}, doi = {10.1007/s00707-023-03598-z}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230525-63822}, pages = {1 -- 21}, abstract = {Identification of modal parameters of a space frame structure is a complex assignment due to a large number of degrees of freedom, close natural frequencies, and different vibrating mechanisms. Research has been carried out on the modal identification of rather simple truss structures. So far, less attention has been given to complex three-dimensional truss structures. This work develops a vibration-based methodology for determining modal information of three-dimensional space truss structures. The method uses a relatively complex space truss structure for its verification. Numerical modelling of the system gives modal information about the expected vibration behaviour. The identification process involves closely spaced modes that are characterised by local and global vibration mechanisms. To distinguish between local and global vibrations of the system, modal strain energies are used as an indicator. The experimental validation, which incorporated a modal analysis employing the stochastic subspace identification method, has confirmed that considering relatively high model orders is required to identify specific mode shapes. Especially in the case of the determination of local deformation modes of space truss members, higher model orders have to be taken into account than in the modal identification of most other types of structures.}, subject = {Fachwerkbau}, language = {en} } @article{KreskowskiRendleFroehlich, author = {Kreskowski, Adrian and Rendle, Gareth and Fr{\"o}hlich, Bernd}, title = {Efficient Direct Isosurface Rasterization of Scalar Volumes}, series = {Computer Graphics Forum}, volume = {2022}, journal = {Computer Graphics Forum}, number = {Volume 4, Issue 7}, publisher = {Wiley Blackwell}, address = {Oxford}, doi = {10.1111/cgf.14670}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230525-63835}, pages = {215 -- 226}, abstract = {In this paper we propose a novel and efficient rasterization-based approach for direct rendering of isosurfaces. Our method exploits the capabilities of task and mesh shader pipelines to identify subvolumes containing potentially visible isosurface geometry, and to efficiently extract primitives which are consumed on the fly by the rasterizer. As a result, our approach requires little preprocessing and negligible additional memory. Direct isosurface rasterization is competitive in terms of rendering performance when compared with ray-marching-based approaches, and significantly outperforms them for increasing resolution in most situations. Since our approach is entirely rasterization based, it affords straightforward integration into existing rendering pipelines, while allowing the use of modern graphics hardware features, such as multi-view stereo for efficient rendering of stereoscopic image pairs for geometry-bound applications. Direct isosurface rasterization is suitable for applications where isosurface geometry is highly variable, such as interactive analysis scenarios for static and dynamic data sets that require frequent isovalue adjustment.}, subject = {Rendering}, language = {en} } @article{SanderWeissermel, author = {Sander, Hendrik and Weißermel, S{\"o}ren}, title = {Urban Heat Transition in Berlin: Corporate Strategies, Political Conflicts, and Just Solutions}, series = {Urban Planning}, volume = {2023}, journal = {Urban Planning}, number = {Volume 8, No 1}, publisher = {Cogitatio Press}, address = {Lissabon}, doi = {10.17645/up.v8i1.6178}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230524-63845}, pages = {361 -- 371}, abstract = {In the field of urban climate policy, heat production and demand are key sectors for achieving a sustainable city. Heat production has to shift from fossil to renewable energies, and the heat demand of most buildings has to be reduced significantly via building retrofits. However, analyses of heat transition still lack its contextualization within entangled urban politico-economic processes and materialities and require critical socio-theoretical examination. Asking about the embeddedness of heat transition within social relations and its implications for social justice issues, this article discusses the challenges and opportunities of heat transition, taking Berlin as an example. It uses an urban political ecology perspective to analyze the materialities of Berlin's heating-housing nexus, its politico-economic context, implications for relations of inequality and power, and its contested strategies. The empirical analysis identifies major disputes about the future trajectory of heat production and about the distribution of retrofit costs. Using our conceptual approach, we discuss these empirical findings against the idea of a more just heat transition. For this purpose, we discuss three policy proposals regarding cost distribution, urban heat planning, and remunicipalization of heat utilities. We argue that this conceptual approach provides huge benefits for debates around heat transition and, more generally, energy justice and just transitions.}, subject = {Berlin}, language = {en} } @article{Bockelmann, author = {Bockelmann, Leo}, title = {Impacts of Change: Analysing the Perception of Industrial Heritage in the Vogtland Region}, series = {Urban Planning}, volume = {2023}, journal = {Urban Planning}, number = {Volume 8, No 1}, publisher = {Cogitatio Press}, address = {Lissabon}, doi = {10.17645/up.v8i1.6025}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230524-63814}, pages = {30 -- 38}, abstract = {Beyond metropolitan areas, many peripheral regions and their cities in Europe have, in manifold ways, been significantly shaped by industrialisation. In the context of the relocation of industrial production to other countries over the last decades, the question has been raised as to the role this heritage can play in futural regional development as well as the potential local identification with this history. Hence, this article seeks to analyse the perception of the industrial heritage in the Vogtland region, located alongside the border of three German federal states and the Czech Republic. It inquires as to the perception of the industrial heritage by the local population and related potential future narrations. Based on spontaneous and explorative interviews with local people as an empirical base, a discrepancy between the perception of the tangible and intangible dimensions of the industrial heritage can be observed. On the one hand, the tangible heritage like older factories and production complexes are seen as a functional legacy and an "eyesore" narrative is attributed to them. On the other hand, people often reference the personal and familial connection to the industry and highlight its importance for the historical development and the wealth of the region. But these positive associations are mainly limited to the intangible dimension and are disconnected from the material artefacts of industrial production.}, subject = {Vogtland}, language = {en} } @article{DamirMeyerAziz, author = {Damir, Mirhan and Meyer, Martin and Aziz, Hellen}, title = {Patterns of Detachment: Spatial Transformations of the Phosphate Industry in el-Quseir, Egypt}, series = {Urban Planning}, volume = {2023}, journal = {Urban Planning}, number = {Volume 8, No 1}, publisher = {Cogitatio Press}, address = {Lissabon}, doi = {10.17645/up.v8i1.6053}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230524-63805}, pages = {1 -- 16}, abstract = {The establishment of phosphate mines and processing plants by Italian entrepreneurs in el-Quseir in 1912 revitalized a town that had faced a steady decline after the opening of the Suez Canal and re-linked it to the world economy. To this day, the now defunct industrial site occupies a large section of physical el-Quseir and plays a key role in its identity. In this article, we explore the impact of the company's successive industrialization and deindustrialization based on archival research, interviews, and mapping. By tracing physical changes on-site and in the city of el-Quseir from the founding of its phosphate industry until today, as well as the historical and current interactions of citizens with the industrial facilities, we hope to better understand the "cluster value" of the industrial plant in quotidian life and the effect of the vacuum left behind after the termination of production. As machinery and buildings are slowly eroding in the absence of expressed interest by the former Italian and current Egyptian owners, we aim to discuss the relationship between the citizens and their el-Quseir phosphate plant as a crucial element of its heritage value at the local level.}, subject = {{\"A}gypten}, language = {en} } @article{GrimmeKollakidouSonderskovZarpetal., author = {Grimme, Sophie Alice and Kollakidou, Avgi and S{\o}nderskov Zarp, Christian and Hornecker, Eva and Kr{\"u}ger, Norbert and Graf, Phillip and Marchetti, Emanuela}, title = {Floor Cleaners as Helper Pets: Projecting Assistive Robots' Agency on Zoomorphic Affordances}, series = {SN Computer Science}, volume = {2023}, journal = {SN Computer Science}, number = {volume 4, article 372}, publisher = {Springer}, address = {Singapur}, doi = {10.1007/s42979-023-01769-2}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230524-63796}, pages = {1 -- 14}, abstract = {Care of ageing adults has become a dominant field of application for assistive robot technologies, promising support for ageing adults residing in care homes and staff, in dealing with practical routine tasks and providing social and emotional relieve. A time consuming and human intensive necessity is the maintenance of high hygiene quality in care homes. Robotic vacuum cleaners have been proven effective for doing the job elsewhere, but—in the context of care homes—are counterproductive for residents' well-being and do not get accepted. This is because people with dementia manifest their agency in more implicit and emotional ways, while making sense of the world around them. Starting from these premises, we explored how a zoomorphic designed vacuum cleaner could better accommodate the sensemaking of people with dementia. Our design reconceptualises robotic vacuum cleaners as a cat-like robot, referring to a playful behaviour and appearance to communicate a non-threatening and familiar role model. Data from an observational study shows that residents responded positively to our prototype, as most of them engaged playfully with it as if it was a pet or a cat-like toy, for example luring it with gestures. Some residents simply ignored the robot, indicating that it was not perceived as frightening or annoying. The level of activity influenced reactions; residents ignored our prototype if busy with other occupations, which proves that it did not cause significant disturbance. We further report results from focus group sessions with formal and informal caregivers who discussed a video prototype of our robot. Caregivers encouraged us to enhance the animal like characteristics (in behaviour and materiality) even further to result in richer interactions and provoke haptic pleasure but also pointed out that residents should not mistake the robot for a real cat.}, subject = {Alter}, language = {en} } @article{AbrahamczykUzair, author = {Abrahamczyk, Lars and Uzair, Aanis}, title = {On the use of climate models for estimating the non-stationary characteristic values of climatic actions in civil engineering practice}, series = {Frontiers in Built Environment}, volume = {2023}, journal = {Frontiers in Built Environment}, number = {volume 9, article 1108328}, publisher = {Frontier Media}, address = {Lausanne}, doi = {10.3389/fbuil.2023.1108328}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230524-63751}, pages = {1 -- 9}, abstract = {The characteristic values of climatic actions in current structural design codes are based on a specified probability of exceedance during the design working life of a structure. These values are traditionally determined from the past observation data under a stationary climate assumption. However, this assumption becomes invalid in the context of climate change, where the frequency and intensity of climatic extremes varies with respect to time. This paper presents a methodology to calculate the non-stationary characteristic values using state of the art climate model projections. The non-stationary characteristic values are calculated in compliance with the requirements of structural design codes by forming quasi-stationary windows of the entire bias-corrected climate model data. Three approaches for the calculation of non-stationary characteristic values considering the design working life of a structure are compared and their consequences on exceedance probability are discussed.}, subject = {Klima{\"a}nderung}, language = {en} } @article{WiegandOsburg, author = {Wiegand, Torben and Osburg, Andrea}, title = {Synthesis, Curing and Thermal Behavior of Amine Hardeners from Potentially Renewable Sources}, series = {Polymers}, volume = {2023}, journal = {Polymers}, number = {volume 15, issue 4, article 990}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/polym15040990}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230524-63745}, pages = {1 -- 12}, abstract = {Research into bio-based epoxy resins has intensified in recent decades. Here, it is of great importance to use raw materials whose use does not compete with food production. In addition, the performance of the newly developed materials should be comparable to that of conventional products. Possible starting materials are lignin degradation products, such as vanillin and syringaldehyde, for which new synthesis routes to the desired products must be found and their properties determined. In this article, the first synthesis of two amine hardeners, starting with vanillin and syringaldehyde, using the Smiles rearrangement reaction is reported. The amine hardeners were mixed with bisphenol A diglycidyl ether, and the curing was compared to isophorone diamine, 4-4′-diaminodiphenyl sulfone, and 4-Aminonbenzylamine by means of differential scanning calorimetry. It was found that the two amines prepared are cold-curing. As TG-MS studies showed, the thermal stability of at least one of the polymers prepared with the potentially bio-based amines is comparable to that of the polymer prepared with isophorone diamine, and similar degradation products are formed during pyrolysis.}, subject = {Epoxide}, language = {en} } @article{AlemuHabteLahmeretal., author = {Alemu, Yohannes L. and Habte, Bedilu and Lahmer, Tom and Urgessa, Girum}, title = {Topologically preoptimized ground structure (TPOGS) for the optimization of 3D RC buildings}, series = {Asian Journal of Civil Engineering}, volume = {2023}, journal = {Asian Journal of Civil Engineering}, publisher = {Springer International Publishing}, address = {Cham}, doi = {10.1007/s42107-023-00640-2}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230517-63677}, pages = {1 -- 11}, abstract = {As an optimization that starts from a randomly selected structure generally does not guarantee reasonable optimality, the use of a systemic approach, named the ground structure, is widely accepted in steel-made truss and frame structural design. However, in the case of reinforced concrete (RC) structural optimization, because of the orthogonal orientation of structural members, randomly chosen or architect-sketched framing is used. Such a one-time fixed layout trend, in addition to its lack of a systemic approach, does not necessarily guarantee optimality. In this study, an approach for generating a candidate ground structure to be used for cost or weight minimization of 3D RC building structures with included slabs is developed. A multiobjective function at the floor optimization stage and a single objective function at the frame optimization stage are considered. A particle swarm optimization (PSO) method is employed for selecting the optimal ground structure. This method enables generating a simple, yet potential, real-world representation of topologically preoptimized ground structure while both structural and main architectural requirements are considered. This is supported by a case study for different floor domain sizes.}, subject = {Bodenmechanik}, language = {en} } @article{GuoAlajlanZhuangetal., author = {Guo, Hongwei and Alajlan, Naif and Zhuang, Xiaoying and Rabczuk, Timon}, title = {Physics-informed deep learning for three-dimensional transient heat transfer analysis of functionally graded materials}, series = {Computational Mechanics}, volume = {2023}, journal = {Computational Mechanics}, publisher = {Springer}, address = {Berlin}, doi = {10.1007/s00466-023-02287-x}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230517-63666}, pages = {1 -- 12}, abstract = {We present a physics-informed deep learning model for the transient heat transfer analysis of three-dimensional functionally graded materials (FGMs) employing a Runge-Kutta discrete time scheme. Firstly, the governing equation, associated boundary conditions and the initial condition for transient heat transfer analysis of FGMs with exponential material variations are presented. Then, the deep collocation method with the Runge-Kutta integration scheme for transient analysis is introduced. The prior physics that helps to generalize the physics-informed deep learning model is introduced by constraining the temperature variable with discrete time schemes and initial/boundary conditions. Further the fitted activation functions suitable for dynamic analysis are presented. Finally, we validate our approach through several numerical examples on FGMs with irregular shapes and a variety of boundary conditions. From numerical experiments, the predicted results with PIDL demonstrate well agreement with analytical solutions and other numerical methods in predicting of both temperature and flux distributions and can be adaptive to transient analysis of FGMs with different shapes, which can be the promising surrogate model in transient dynamic analysis.}, subject = {W{\"a}rme{\"u}bergang}, language = {en} } @article{RabczukZhuangOterkus, author = {Rabczuk, Timon and Zhuang, Xiaoying and Oterkus, Erkan}, title = {Editorial: Computational modeling based on nonlocal theory}, series = {Engineering with Computers}, volume = {2023}, journal = {Engineering with Computers}, number = {Volume 39, issue 3}, publisher = {Springer}, address = {London}, doi = {https://doi.org/10.1007/s00366-022-01775-7}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230517-63658}, pages = {1}, abstract = {Nonlocal theories concern the interaction of objects, which are separated in space. Classical examples are Coulomb's law or Newton's law of universal gravitation. They had signficiant impact in physics and engineering. One classical application in mechanics is the failure of quasi-brittle materials. While local models lead to an ill-posed boundary value problem and associated mesh dependent results, nonlocal models guarantee the well-posedness and are furthermore relatively easy to implement into commercial computational software.}, subject = {Computersimulation}, language = {en} } @article{KraazKoopWunschetal., author = {Kraaz, Luise and Koop, Maria and Wunsch, Maximilian and Plank-Wiedenbeck, Uwe}, title = {The Scaling Potential of Experimental Knowledge in the Case of the Bauhaus.MobilityLab, Erfurt (Germany)}, series = {Urban Planning}, volume = {2022}, journal = {Urban Planning}, number = {Volume 7, Issue 3}, doi = {10.17645/up.v7i3.5329}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230509-63633}, pages = {274 -- 284}, abstract = {Real-world labs hold the potential to catalyse rapid urban transformations through real-world experimentation. Characterised by a rather radical, responsive, and location-specific nature, real-world labs face constraints in the scaling of experimental knowledge. To make a significant contribution to urban transformation, the produced knowledge must go beyond the level of a building, street, or small district where real-world experiments are conducted. Thus, a conflict arises between experimental boundaries and the stimulation of broader implications. The challenges of scaling experimental knowledge have been recognised as a problem, but remain largely unexplained. Based on this, the article will discuss the applicability of the "typology of amplification processes" by Lam et al. (2020) to explore and evaluate the potential of scaling experimental knowledge from real-world labs. The application of the typology is exemplified in the case of the Bauhaus.MobilityLab. The Bauhaus.MobilityLab takes a unique approach by testing and developing cross-sectoral mobility, energy, and logistics solutions with a distinct focus on scaling knowledge and innovation. For this case study, different qualitative research techniques are combined according to "within-method triangulation" and synthesised in a strengths, weaknesses, opportunities, and threats (SWOT) analysis. The analysis of the Bauhaus.MobilityLab proves that the "typology of amplification processes" is useful as a systematic approach to identifying and evaluating the potential of scaling experimental knowledge.}, subject = {Stadtplanung}, language = {en} } @article{SimonRitz, author = {Simon-Ritz, Frank}, title = {"Kultur ist Reichtum an Problemen": Wie sich der Kultur-Begriff der UNESCO an Egon Friedell ann{\"a}herte}, series = {Palmbaum: Literarisches Journal aus Th{\"u}ringen}, volume = {2023}, journal = {Palmbaum: Literarisches Journal aus Th{\"u}ringen}, number = {Heft 1}, publisher = {Quartus Verlag}, address = {Bucha bei Jena}, doi = {10.25643/bauhaus-universitaet.4952}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230411-49524}, pages = {4}, abstract = {Der in H. 1/2023 erschienene Essay f{\"u}hrt Gedanken einer in H. 1/2022 des "Palmbaum" erschienene Betrachtung (https://doi.org/10.25643/bauhaus-universitaet.4628) weiter. Im Zentrum stehen dabei die Bem{\"u}hungen der UNESCO um das immaterielle Kulturerbe.}, subject = {UNESCO}, language = {de} } @article{LondongBarthSoebke, author = {Londong, J{\"o}rg and Barth, Marcus and S{\"o}bke, Heinrich}, title = {Reducing antimicrobial resistances by source separation of domestic wastewater}, series = {Frontiers in Environmental Health}, volume = {2023}, journal = {Frontiers in Environmental Health}, number = {Volume 2, article 1151898}, publisher = {Frontiers Media}, address = {Lausanne}, doi = {10.3389/fenvh.2023.1151898}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230403-49483}, pages = {1 -- 5}, abstract = {Antimicrobial resistances (AMR) are ranked among the top ten threats to public health and societal development worldwide. Toilet wastewater contained in domestic wastewater is a significant source of AMR entering the aquatic environment. The current commonly implemented combined sewer systems at times cause overflows during rain events, resulting in the discharge of untreated wastewater into the aquatic environment, thus promoting AMR. In this short research article, we describe an approach to transform combined sewer systems into source separation-modified combined sewer systems that separately treat toilet wastewater. We employ simulations for demonstrating that source separation-modified combined sewer systems reduce the emission of AMR- causing substances by up to 11.5 logarithm levels. Thus, source separation- modified combined sewer systems are amongst the most effective means of combating AMR. KEYWORDS}, subject = {Allgemeinheit}, language = {en} } @article{WellbrockLobigsErbrichetal., author = {Wellbrock, Christian-Mathias and Lobigs, Frank and Erbrich, Lukas and Buschow, Christopher}, title = {Coopetition is King. {\"O}konomische Potentiale und medienpolitische Implikationen kooperativer Journalismusplattformen}, volume = {2023}, publisher = {Landesanstalt f{\"u}r Medien NRW}, address = {D{\"u}sseldorf}, doi = {10.25643/bauhaus-universitaet.4947}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230320-49473}, pages = {1 -- 48}, abstract = {Die vorliegende Studie geht der Fragestellung nach, wie sich eine anbieter{\"u}bergreifende, abonnementbasierte Plattform f{\"u}r den digitalen Journalismus, also eine Art Spotify im Journalismus, auf die Ums{\"a}tze der Anbieter journalistischer Inhalte und die Abonnements im Digitaljournalismus in Deutschland auswirken w{\"u}rde. Auf Basis drei sich erg{\"a}nzender Sch{\"a}tzmethoden f{\"u}r Zahlungsbereitschaft, die in zwei Repr{\"a}sentativbefragungen der deutschen Online-Bev{\"o}lkerung mit insgesamt 8.000 Teilnehmenden angewandt wurden, gelangt das Whitepaper zu den folgenden Schl{\"u}sselbefunden.}, subject = {Journalistik}, language = {de} } @article{AnsariZachariasKoenke, author = {Ansari, Meisam and Zacharias, Christin and K{\"o}nke, Carsten}, title = {Metaconcrete: An Experimental Study on the Impact of the Core-Coating Inclusions on Mechanical Vibration}, series = {materials}, volume = {2023}, journal = {materials}, number = {Volume 16, Issue 5, article 1836}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/ma16051836}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230315-49370}, pages = {1 -- 18}, abstract = {Resonance vibration of structures is an unpleasant incident that can be conventionally avoided by using a Tuned Mass Damper (TMD). The scope of this paper contains the utilization of engineered inclusions in concrete as damping aggregates to suppress resonance vibration similar to a TMD. The inclusions are composed of a stainless-steel core with a spherical shape coated with silicone. This configuration has been the subject of several studies and it is best known as Metaconcrete. This paper presents the procedure of a free vibration test conducted with two small-scaled concrete beams. The beams exhibited a higher damping ratio after the core-coating element was secured to them. Subsequently, two meso-models of small-scaled beams were created: one representing conventional concrete and the other representing concrete with the core-coating inclusions. The frequency response curves of the models were obtained. The change in the response peak verified the ability of the inclusions to suppress the resonance vibration. This study concludes that the core-coating inclusions can be utilized in concrete as damping aggregates.}, subject = {Beton}, language = {en} } @article{AlsaadSchaelteSchneeweissetal., author = {Alsaad, Hayder and Sch{\"a}lte, Gereon and Schneeweiß, Mario and Becher, Lia and Pollack, Moritz and Gena, Amayu Wakoya and Schweiker, Marcel and Hartmann, Maria and Voelker, Conrad and Rossaint, Rolf and Irrgang, Matthias}, title = {The Spread of Exhaled Air and Aerosols during Physical Exercise}, series = {Journal of Clinical Medicine}, volume = {2023}, journal = {Journal of Clinical Medicine}, number = {Volume 12, issue 4, article 1300}, publisher = {Basel}, address = {MDPI}, doi = {10.3390/jcm12041300}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230208-49262}, pages = {20}, abstract = {Physical exercise demonstrates a special case of aerosol emission due to its associated elevated breathing rate. This can lead to a faster spread of airborne viruses and respiratory diseases. Therefore, this study investigates cross-infection risk during training. Twelve human subjects exercised on a cycle ergometer under three mask scenarios: no mask, surgical mask, and FFP2 mask. The emitted aerosols were measured in a grey room with a measurement setup equipped with an optical particle sensor. The spread of expired air was qualitatively and quantitatively assessed using schlieren imaging. Moreover, user satisfaction surveys were conducted to evaluate the comfort of wearing face masks during training. The results indicated that both surgical and FFP2 masks significantly reduced particles emission with a reduction efficiency of 87.1\% and 91.3\% of all particle sizes, respectively. However, compared to surgical masks, FFP2 masks provided a nearly tenfold greater reduction of the particle size range with long residence time in the air (0.3-0.5 μm). Furthermore, the investigated masks reduced exhalation spreading distances to less than 0.15 m and 0.1 m in the case of the surgical mask and FFP2 mask, respectively. User satisfaction solely differed with respect to perceived dyspnea between no mask and FFP2 mask conditions.}, subject = {Sport}, language = {en} } @article{BapirAbrahamczykWichtmannetal., author = {Bapir, Baban and Abrahamczyk, Lars and Wichtmann, Torsten and Prada-Sarmiento, Luis Felipe}, title = {Soil-structure interaction: A state-of-the-art review of modeling techniques and studies on seismic response of building structures}, series = {Frontiers in Built Environment}, volume = {2023}, journal = {Frontiers in Built Environment}, number = {Volume 9}, editor = {Ozturk, Baki}, publisher = {Frontiers Media}, address = {Lausanne}, doi = {10.3389/fbuil.2023.1120351}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230206-49190}, pages = {1 -- 17}, abstract = {The present article aims to provide an overview of the consequences of dynamic soil-structure interaction (SSI) on building structures and the available modelling techniques to resolve SSI problems. The role of SSI has been traditionally considered beneficial to the response of structures. However, contemporary studies and evidence from past earthquakes showed detrimental effects of SSI in certain conditions. An overview of the related investigations and findings is presented and discussed in this article. Additionally, the main approaches to evaluate seismic soil-structure interaction problems with the commonly used modelling techniques and computational methods are highlighted. The strength, limitations, and application cases of each model are also discussed and compared. Moreover, the role of SSI in various design codes and global guidelines is summarized. Finally, the advancements and recent findings on the SSI effects on the seismic response of buildings with different structural systems and foundation types are presented. In addition, with the aim of helping new researchers to improve previous findings, the research gaps and future research tendencies in the SSI field are pointed out.}, subject = {Boden-Bauwerk-Wechselwirkung}, language = {en} } @article{AicherBoermelLondongetal., author = {Aicher, Andreas and B{\"o}rmel, Melanie and Londong, J{\"o}rg and Beier, Silvio}, title = {Vertical green system for gray water treatment: Analysis of the VertiKKA-module in a field test}, series = {Frontiers in Environmental Science}, volume = {2022}, journal = {Frontiers in Environmental Science}, number = {Volume 10 (2022), article 976005}, publisher = {Frontiers Media}, address = {Lausanne}, doi = {10.3389/fenvs.2022.976005}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48840}, pages = {1 -- 7}, abstract = {This work presents a modular Vertical Green System (VGS) for gray water treatment, developed at the Bauhaus-Universit{\"a}t Weimar. The concept was transformed into a field study with four modules built and tested with synthetic gray water. Each module set contains a small and larger module with the same treatment substrate and was fed hourly. A combination of lightweight structural material and biochar of agricultural residues and wood chips was used as the treatment substrate. In this article, we present the first 18 weeks of operation. Regarding the treatment efficiency, the parameters chemical oxygen demand (COD), total phosphorous (TP), ortho-phosphate (ortho-P), total bound nitrogen (TNb), ammonium nitrogen (NH4-N), and nitrate nitrogen (NO3-N) were analyzed and are presented in this work. The results of the modules with agricultural residues are promising. Up to 92\% COD reduction is stated in the data. The phosphate and nitrogen fractions are reduced significantly in these modules. By contrast, the modules with wood chips reduce only 67\% of the incoming COD and respectively less regarding phosphates and the nitrogen fraction.}, subject = {Grauwasser}, language = {en} } @article{Coenen, author = {Coenen, Ekkehard}, title = {Communicative Action, Objectifications, and the Triad of Violence}, series = {Human Studies}, volume = {2022}, journal = {Human Studies}, number = {45 (2022)}, publisher = {Springer Science + Business Media B.V}, address = {Dordrecht}, doi = {10.1007/s10746-022-09639-1}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48828}, pages = {447 -- 468}, abstract = {This article aims to develop a social theory of violence that emphasizes the role of the third party as well as the communication between the involved subjects. For this Teresa Koloma Beck's essay 'The Eye of the Beholder: Violence as a Social Process' is taken as a starting point, which adopts a social-constructivist perspective. On the one hand, the basic concepts and the benefits of this approach are presented. On the other hand, social-theoretical problems of this approach are revealed. These deficits are counteracted by expanding Koloma Beck's approach with a communicative-constructivist framework. Thus, the role of communicative action and the 'objectification of violence' is emphasized. These aspects impact the perception, judgement and (de-)legitimation of violence phenomena and the emergence of a 'knowledge of violence'. Communicative actions and objectifications form a key to understanding violent interactions and the link between the micro and macro levels. Finally, the methodological consequences for the research of violence and Communicative Constructivism are discussed. Furthermore, possible research fields are outlined, which open up by looking at communicative action and the objectifications within the 'triads of violence'.}, subject = {Gewalt}, language = {en} } @article{Stadler, author = {Stadler, Max}, title = {Gr{\"u}nderzeit. Hightech und Alternativen der Wissenschaft in West-Berlin}, series = {NTM Zeitschrift f{\"u}r Geschichte der Wissenschaften, Technik und Medizin}, volume = {2022}, journal = {NTM Zeitschrift f{\"u}r Geschichte der Wissenschaften, Technik und Medizin}, number = {30 (2022)}, publisher = {Basel}, address = {Birkh{\"a}user}, doi = {10.1007/s00048-022-00352-9}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48800}, pages = {599 -- 632}, abstract = {Zu den diversen Unternehmungen sozialbewegter „Gegenwissenschaft", die um 1980 auf der Bildfl{\"a}che der BRD erschienen, z{\"a}hlte der 1982 gegr{\"u}ndete Berliner Wissenschaftsladen e. V., kurz WILAB - eine Art „alternatives" Spin-off der Technischen Universit{\"a}t Berlin. Der vorliegende Beitrag situiert die Ausgr{\"u}ndung des „Ladens" im Kontext zeitgen{\"o}ssischer Fortschritte der (regionalen) Forschungs- und Technologiepolitik. Gezeigt wird, wie der deindustrialisierenden Inselstadt, qua „innovationspolitischer" Gegensteuerung, dabei sogar eine gewisse Vorreiterrolle zukam: {\"u}ber die Stadtgrenzen hinaus sichtbare Neuerungen wie die Gr{\"u}ndermesse BIG TECH oder das 1983 er{\"o}ffnete Berliner Innovations- und Gr{\"u}nderzentrum (BIG), der erste „Incubator" [sic] der BRD, etwa gingen auf das Konto der 1977/78 lancierten Technologie-Transferstelle der TU Berlin, TU-transfer. Anders gesagt: tendenziell bekam man es hier nun mit Verh{\"a}ltnissen zu tun, die immer weniger mit den Tr{\"a}umen einer „kritischen", nicht-fremdbestimmten (Gegen‑)Wissenschaft kompatibel waren. Latent kontr{\"a}r zur historiographischen Prominenz des wissenschaftskritischen Zeitgeists fristeten „alternativen" Zielsetzungen verpflichtete Unternehmungen wie „WILAB" ein relativ marginalisiertes Nischendasein. Dennoch wirft das am WILAB verfolgte, so gesehen wenig aussichtsreiche Anliegen, eine andere, n{\"a}mlich „humanere" Informationstechnologie in die Wege zu leiten, ein instruktives Licht auf die Aufbr{\"u}che „unternehmerischer" Wissenschaft in der BRD um 1980.}, subject = {Berlin }, language = {de} } @article{HahlbrockBraunHeideletal., author = {Hahlbrock, David and Braun, Michael and Heidel, Robin and Lemmen, Patrik and Boumann, Roland and Bruckmann, Tobias and Schramm, Dieter and Helm, Volker and Willmann, Jan}, title = {Cable Robotic 3D-printing: additive manufacturing on the construction site}, series = {Construction Robotics}, volume = {2022}, journal = {Construction Robotics}, publisher = {Springer International Publishing}, address = {Cham}, doi = {10.1007/s41693-022-00082-3}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48791}, pages = {1 -- 14}, abstract = {This paper outlines an important step in characterizing a novel field of robotic construction research where a cable-driven parallel robot is used to extrude cementitious material in three-dimensional space, and thus offering a comprehensive new approach to computational design and construction, and to robotic fabrication at larger scales. Developed by the Faculty of Art and Design at Bauhaus-University Weimar (Germany), the faculty of Architecture at the University of Applied Sciences Dortmund (Germany) and the Chair of Mechatronics at the University of Duisburg-Essen (Germany), this approach offers unique advantages over existing additive manufacturing methods: the system is easily transportable and scalable, it does not require additional formwork or scaffolding, and it offers digital integration and informational oversight across the entire design and building process. This paper considers 1) key research components of cable robotic 3D-printing (such as computational design, material exploration, and robotic control), and 2) the integration of these parameters into a unified design and building process. The demonstration of the approach at full-scale is of particular concern.}, subject = {Robotik}, language = {en} } @article{MoscosoKraus, author = {Moscoso, Caridad and Kraus, Matthias}, title = {On the Verification of Beams Subjected to Lateral Torsional Buckling by Simplified Plastic Structural Analysis}, series = {ce/papers}, volume = {2022}, journal = {ce/papers}, number = {Volume 5, Issue 4}, publisher = {Ernst \& Sohn}, address = {Berlin}, doi = {10.1002/cepa.1835}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48782}, pages = {914 -- 923}, abstract = {Plastic structural analysis may be applied without any difficulty and with little effort for structural member verifications with regard to lateral torsional buckling of doubly symmetric rolled I sections. Suchlike analyses can be performed based on the plastic zone theory, specifically using finite beam elements with seven degrees of freedom and 2nd order theory considering material nonlinearity. The existing Eurocode enables these approaches and the coming-up generation will provide corresponding regulations in EN 1993-1-14. The investigations allow the determination of computationally accurate limit loads, which are determined in the present paper for selected structural systems with different sets of parameters, such as length, steel grade and cross section types. The results are compared to approximations gained by more sophisticated FEM analyses (commercial software Ansys Workbench applying solid elements) for reasons of verification/validation. In this course, differences in the results of the numerical models are addressed and discussed. In addition, results are compared to resistances obtained by common design regulations based on reduction factors χlt including regulations of EN 1993-1-1 (including German National Annex) as well as prEN 1993-1-1: 2020-08 (proposed new Eurocode generation). Concluding, correlations of results and their advantages as well as disadvantages are discussed.}, subject = {Stahl}, language = {en} } @article{Morawski, author = {Morawski, Tommaso}, title = {La tavola e la mappa. Paradigmi per una metaforologia mediale dell'immaginazione cartografica in Kant}, series = {Philosophy Kitchen}, volume = {2022}, journal = {Philosophy Kitchen}, number = {17, II/2022}, publisher = {Universit{\`a} degli Studi di Torino}, address = {Turino}, doi = {10.13135/2385-1945/7191}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48766}, pages = {137 -- 152}, abstract = {Immanuel Kant's thought is a central historical and theoretical reference in Hans Blumenberg's metaphorological project. This is demonstrated by the fact that in the Paradigms the author outlines the concept of absolute metaphor by explicitly referring to \S59 of the Critique of the Power of Judgment and recognizing in the Kantian symbol a model for his own metaphorics. However, Kant's name also appears in the chapter on the metaphor of the "terra incognita" that not only did he theorize the presence of symbolic hypotyposis in our language [...] but also made extensive use of metaphors linked to "determinate historical experiences". In particular: geographical metaphors. In my essay, I would like to start from the analysis of Kant's geographical metaphors in order to try to rethink Blumenberg's archaeological method as an archaeology of media that grounds the study of metaphors in the materiality of communication and the combination of tools, agents and media.}, subject = {Kant, Immanuel}, language = {it} } @article{BuschowWellbrock, author = {Buschow, Christopher and Wellbrock, Christian-Mathias}, title = {"Spotify for News"? User Perception of Subscription-Based Content Platforms for News Media}, series = {Journalism and Media}, volume = {2022}, journal = {Journalism and Media}, number = {2023, 4}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/journalmedia4010001}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230124-48740}, pages = {1 -- 15}, abstract = {Subscription-based news platforms (such as "Apple News+" or "Readly") that bundle content from different publishers into one comprehensive package and offer it to media users at a fixed monthly rate are a new way of accessing and consuming digital journalism. These services have received little attention in journalism studies, although they differ greatly from traditional media products and distribution channels. This article empirically investigates the perception of journalism platforms based on eight qualitative focus group discussions with 55 German news consumers. Results show that the central characteristics these platforms should fulfill in order to attract users are strikingly similar to the characteristics of media platforms from the music and video industries, in particular regarding price points, contract features, and modes of usage. Against this background, the potential and perspectives of a subscription-based news platform for journalism's societal role are discussed.}, subject = {Journalistik}, language = {en} } @article{AlaladeReichertKoehnetal., author = {Alalade, Muyiwa and Reichert, Ina and K{\"o}hn, Daniel and Wuttke, Frank and Lahmer, Tom}, title = {A Cyclic Multi-Stage Implementation of the Full-Waveform Inversion for the Identification of Anomalies in Dams}, series = {Infrastructures}, volume = {2022}, journal = {Infrastructures}, number = {Volume 7, issue 12, article 161}, editor = {Qu, Chunxu and Gao, Chunxu and Zhang, Rui and Jia, Ziguang and Li, Jiaxiang}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/infrastructures7120161}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221201-48396}, pages = {19}, abstract = {For the safe and efficient operation of dams, frequent monitoring and maintenance are required. These are usually expensive, time consuming, and cumbersome. To alleviate these issues, we propose applying a wave-based scheme for the location and quantification of damages in dams. To obtain high-resolution "interpretable" images of the damaged regions, we drew inspiration from non-linear full-multigrid methods for inverse problems and applied a new cyclic multi-stage full-waveform inversion (FWI) scheme. Our approach is less susceptible to the stability issues faced by the standard FWI scheme when dealing with ill-posed problems. In this paper, we first selected an optimal acquisition setup and then applied synthetic data to demonstrate the capability of our approach in identifying a series of anomalies in dams by a mixture of reflection and transmission tomography. The results had sufficient robustness, showing the prospects of application in the field of non-destructive testing of dams.}, subject = {Damm}, language = {en} } @article{ArnoldKraus, author = {Arnold, Robert and Kraus, Matthias}, title = {On the nonstationary identification of climate-influenced loads for the semi-probabilistic approach using measured and projected data}, series = {Cogent Engineering}, volume = {2022}, journal = {Cogent Engineering}, number = {Volume 9, issue 1, article 2143061}, editor = {Pham, Duc}, publisher = {Taylor \& Francis}, address = {London}, doi = {10.1080/23311916.2022.2143061}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221117-47363}, pages = {1 -- 26}, abstract = {A safe and economic structural design based on the semi-probabilistic concept requires statistically representative safety elements, such as characteristic values, design values, and partial safety factors. Regarding climate loads, the safety levels of current design codes strongly reflect experiences based on former measurements and investigations assuming stationary conditions, i.e. involving constant frequencies and intensities. However, due to climate change, occurrence of corresponding extreme weather events is expected to alter in the future influencing the reliability and safety of structures and their components. Based on established approaches, a systematically refined data-driven methodology for the determination of design parameters considering nonstationarity as well as standardized targets of structural reliability or safety, respectively, is therefore proposed. The presented procedure picks up fundamentals of European standardization and extends them with respect to nonstationarity by applying a shifting time window method. Taking projected snow loads into account, the application of the method is exemplarily demonstrated and various influencing parameters are discussed.}, subject = {Reliabilit{\"a}t}, language = {en} } @article{Lutolli, author = {Lutolli, Blerim}, title = {A Review of Domed Cities and Architecture: Past, Present and Future}, series = {Future cities and environment}, volume = {2022}, journal = {Future cities and environment}, number = {Volume 8, issue 1}, publisher = {Ubiquity Press Limited}, address = {London}, doi = {10.5334/fce.154}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221103-47335}, pages = {1 -- 9}, abstract = {The goal of architecture is changing in response to the expanding role of cities, rapid urbanization, and transformation under changing economic, environmental, social, and demographic factors. As cities increased in the early modern era, overcrowding, urbanization, and pollution conditions led reformers to consider the future shape of the cities. One of the most critical topics in contemporary architecture is the subject of the future concepts of living. In most cases, domed cities, as a future concept of living, are rarely considered, and they are used chiefly as "utopian" visions in the discourse of future ways of living. This paper highlights the reviews of domed cities to deepen the understanding of the idea in practice, like its approach in terms of architecture. The main aim of this paper is to provide a broad overview for domed cities in the face of pollution as one of the main concerns in many European cities. As a result, the significance of the reviews of the existing projects is focused on their conceptual quality. This review will pave the way for further studies in terms of future developments in the realm of domed cities. In this paper, the city of Celje, one of the most polluted cities in Slovenia, is taken as a case study for considering the concept of Dome incorporated due to the lack of accessible literature on the topic. This review's primary contribution is to allow architects to explore a broad spectrum of innovation by comparing today's achievable statuses against the possibilities generated by domed cities. As a result of this study, the concept of living under the Dome remains to be developed in theory and practice. The current challenging climatic situation will accelerate the evolution of these concepts, resulting in the formation of new typologies, which are a requirement for humanity.}, subject = {Architektur}, language = {en} } @article{ChowdhuryKraus, author = {Chowdhury, Sharmistha and Kraus, Matthias}, title = {Design-related reassessment of structures integrating Bayesian updating of model safety factors}, series = {Results in Engineering}, volume = {2022}, journal = {Results in Engineering}, number = {Volume 16, article 100560}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.rineng.2022.100560}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221028-47294}, pages = {1 -- 1}, abstract = {In the semi-probabilistic approach of structural design, the partial safety factors are defined by considering some degree of uncertainties to actions and resistance, associated with the parameters' stochastic nature. However, uncertainties for individual structures can be better examined by incorporating measurement data provided by sensors from an installed health monitoring scheme. In this context, the current study proposes an approach to revise the partial safety factor for existing structures on the action side, γE by integrating Bayesian model updating. A simple numerical example of a beam-like structure with artificially generated measurement data is used such that the influence of different sensor setups and data uncertainties on revising the safety factors can be investigated. It is revealed that the health monitoring system can reassess the current capacity reserve of the structure by updating the design safety factors, resulting in a better life cycle assessment of structures. The outcome is furthermore verified by analysing a real life small railway steel bridge ensuring the applicability of the proposed method to practical applications.}, subject = {Lebenszyklus}, language = {en} } @article{ChowdhuryZabel, author = {Chowdhury, Sharmistha and Zabel, Volkmar}, title = {Influence of loading sequence on wind induced fatigue assessment of bolts in TV-tower connection block}, series = {Results in Engineering}, volume = {2022}, journal = {Results in Engineering}, number = {Volume 16, article 100603}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.rineng.2022.100603}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221028-47303}, pages = {1 -- 18}, abstract = {Bolted connections are widely employed in structures like transmission poles, wind turbines, and television (TV) towers. The behaviour of bolted connections is often complex and plays a significant role in the overall dynamic characteristics of the structure. The goal of this work is to conduct a fatigue lifecycle assessment of such a bolted connection block of a 193 m tall TV tower, for which 205 days of real measurement data have been obtained from the installed monitoring devices. Based on the recorded data, the best-fit stochastic wind distribution for 50 years, the decisive wind action, and the locations to carry out the fatigue analysis have been decided. A 3D beam model of the entire tower is developed to extract the nodal forces corresponding to the connection block location under various mean wind speeds, which is later coupled with a detailed complex finite element model of the connection block, with over three million degrees of freedom, for acquiring stress histories on some pre-selected bolts. The random stress histories are analysed using the rainflow counting algorithm (RCA) and the damage is estimated using Palmgren-Miner's damage accumulation law. A modification is proposed to integrate the loading sequence effect into the RCA, which otherwise is ignored, and the differences between the two RCAs are investigated in terms of the accumulated damage.}, subject = {Schadensakkumulation}, language = {en} } @article{HarirchianIsik, author = {Harirchian, Ehsan and Isik, Ercan}, title = {A Comparative Probabilistic Seismic Hazard Analysis for Eastern Turkey (Bitlis) Based on Updated Hazard Map and Its Effect on Regular RC Structures}, series = {Buildings}, volume = {2022}, journal = {Buildings}, number = {Volume 12, issue 10, article 1573}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/buildings12101573}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221028-47283}, pages = {1 -- 19}, abstract = {Determining the earthquake hazard of any settlement is one of the primary studies for reducing earthquake damage. Therefore, earthquake hazard maps used for this purpose must be renewed over time. Turkey Earthquake Hazard Map has been used instead of Turkey Earthquake Zones Map since 2019. A probabilistic seismic hazard was performed by using these last two maps and different attenuation relationships for Bitlis Province (Eastern Turkey) were located in the Lake Van Basin, which has a high seismic risk. The earthquake parameters were determined by considering all districts and neighborhoods in the province. Probabilistic seismic hazard analyses were carried out for these settlements using seismic sources and four different attenuation relationships. The obtained values are compared with the design spectrum stated in the last two earthquake maps. Significant differences exist between the design spectrum obtained according to the different exceedance probabilities. In this study, adaptive pushover analyses of sample-reinforced concrete buildings were performed using the design ground motion level. Structural analyses were carried out using three different design spectra, as given in the last two seismic design codes and the mean spectrum obtained from attenuation relationships. Different design spectra significantly change the target displacements predicted for the performance levels of the buildings.}, subject = {Erbeben}, language = {en} } @article{MaiwaldSchwarzKaufmannetal., author = {Maiwald, Holger and Schwarz, Jochen and Kaufmann, Christian and Langhammer, Tobias and Golz, Sebastian and Wehner, Theresa}, title = {Innovative Vulnerability and Risk Assessment of Urban Areas against Flood Events: Prognosis of Structural Damage with a New Approach Considering Flow Velocity}, series = {Water}, volume = {2022}, journal = {Water}, number = {Volume 14, issue 18, article 2793}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/w14182793}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221012-47254}, pages = {1 -- 28}, abstract = {The floods in 2002 and 2013, as well as the recent flood of 2021, caused billions Euros worth of property damage in Germany. The aim of the project Innovative Vulnerability and Risk Assessment of Urban Areas against Flood Events (INNOVARU) involved the development of a practicable flood damage model that enables realistic damage statements for the residential building stock. In addition to the determination of local flood risks, it also takes into account the vulnerability of individual buildings and allows for the prognosis of structural damage. In this paper, we discuss an improved method for the prognosis of structural damage due to flood impact. Detailed correlations between inundation level and flow velocities depending on the vulnerability of the building types, as well as the number of storeys, are considered. Because reliable damage data from events with high flow velocities were not available, an innovative approach was adopted to cover a wide range of flow velocities. The proposed approach combines comprehensive damage data collected after the 2002 flood in Germany with damage data of the 2011 Tohoku earthquake tsunami in Japan. The application of the developed methods enables a reliable reinterpretation of the structural damage caused by the August flood of 2002 in six study areas in the Free State of Saxony.}, subject = {Bauschaden}, language = {en} } @article{MehlingSchnabelLondong, author = {Mehling, Simon and Schnabel, Tobias and Londong, J{\"o}rg}, title = {Investigation on Energetic Efficiency of Reactor Systems for Oxidation of Micro-Pollutants by Immobilized Active Titanium Dioxide Photocatalysis}, series = {Water}, volume = {2022}, journal = {Water}, number = {Volume 14, issue 7, article 2681}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/w14172681}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220912-47130}, pages = {1 -- 15}, abstract = {In this work, the degradation performance for the photocatalytic oxidation of eight micropollutants (amisulpride, benzotriazole, candesartan, carbamazepine, diclofenac, gabapentin, methlybenzotriazole, and metoprolol) within real secondary effluent was investigated using three different reactor designs. For all reactor types, the influence of irradiation power on its reaction rate and energetic efficiency was investigated. Flat cell and batch reactor showed almost similar substance specific degradation behavior. Within the immersion rotary body reactor, benzotriazole and methylbenzotriazole showed a significantly lower degradation affinity. The flat cell reactor achieved the highest mean degradation rate, with half time values ranging from 5 to 64 min with a mean of 18 min, due to its high catalysts surface to hydraulic volume ratio. The EE/O values were calculated for all micro-pollutants as well as the mean degradation rate constant of each experimental step. The lowest substance specific energy per order (EE/O) values of 5 kWh/m3 were measured for benzotriazole within the batch reactor. The batch reactor also reached the lowest mean values (11.8-15.9 kWh/m3) followed by the flat cell reactor (21.0-37.0 kWh/m3) and immersion rotary body reactor (23.9-41.0 kWh/m3). Catalyst arrangement and irradiation power were identified as major influences on the energetic performance of the reactors. Low radiation intensities as well as the use of submerged catalyst arrangement allowed a reduction in energy demand by a factor of 3-4. A treatment according to existing treatment goals of wastewater treatment plants (80\% total degradation) was achieved using the batch reactor with a calculated energy demand of 7000 Wh/m3.}, subject = {Fotokatalyse}, language = {en} } @article{AlYasiriMutasharGuerlebecketal., author = {Al-Yasiri, Zainab Riyadh Shaker and Mutashar, Hayder Majid and G{\"u}rlebeck, Klaus and Lahmer, Tom}, title = {Damage Sensitive Signals for the Assessment of the Conditions of Wind Turbine Rotor Blades Using Electromagnetic Waves}, series = {Infrastructures}, volume = {2022}, journal = {Infrastructures}, number = {Volume 7, Issue 8 (August 2022), article 104}, editor = {Shafiullah, GM}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/infrastructures7080104}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220831-47093}, pages = {18}, abstract = {One of the most important renewable energy technologies used nowadays are wind power turbines. In this paper, we are interested in identifying the operating status of wind turbines, especially rotor blades, by means of multiphysical models. It is a state-of-the-art technology to test mechanical structures with ultrasonic-based methods. However, due to the density and the required high resolution, the testing is performed with high-frequency waves, which cannot penetrate the structure in depth. Therefore, there is a need to adopt techniques in the fields of multiphysical model-based inversion schemes or data-driven structural health monitoring. Before investing effort in the development of such approaches, further insights and approaches are necessary to make the techniques applicable to structures such as wind power plants (blades). Among the expected developments, further accelerations of the so-called "forward codes" for a more efficient implementation of the wave equation could be envisaged. Here, we employ electromagnetic waves for the early detection of cracks. Because in many practical situations, it is not possible to apply techniques from tomography (characterized by multiple sources and sensor pairs), we focus here on the question of whether the existence of cracks can be determined by using only one source for the sent waves.}, subject = {Windkraftwerk}, language = {en} } @article{ArtusKoch, author = {Artus, Mathias and Koch, Christian}, title = {Object-Oriented Damage Information Modeling Concepts and Implementation for Bridge Inspection}, series = {Journal of Computing in Civil Engineering}, volume = {2022}, journal = {Journal of Computing in Civil Engineering}, number = {Volume 36, issue 6}, doi = {10.1061/(ASCE)CP.1943-5487.0001030}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220826-47087}, pages = {1 -- 21}, abstract = {Bridges are designed to last for more than 50 years and consume up to 50\% of their life-cycle costs during their operation phase. Several inspections and assessment actions are executed during this period. Bridge and damage information must be gathered, digitized, and exchanged between different stakeholders. Currently, the inspection and assessment practices rely on paper-based data collection and exchange, which is time-consuming and error-prone, and leads to loss of information. Storing and exchanging damage and building information in a digital format may lower costs and errors during inspection and assessment and support future needs, for example, immediate simulations regarding performance assessment, automated maintenance planning, and mixed reality inspections. This study focused on the concept for modeling damage information to support bridge reviews and structural analysis. Starting from the definition of multiple use cases and related requirements, the data model for damage information is defined independently from the subsequent implementation. In the next step, the implementation via an established standard is explained. Functional tests aim to identify problems in the concept and implementation. To show the capability of the final model, two example use cases are illustrated: the inspection review of the entire bridge and a finite-element analysis of a single component. Main results are the definition of necessary damage data, an object-oriented damage model, which supports multiple use cases, and the implementation of the model in a standard. Furthermore, the tests have shown that the standard is suitable to deliver damage information; however, several software programs lack proper implementation of the standard.}, subject = {Building Information Modeling}, language = {en} } @article{PatzeltErfurtLudwig, author = {Patzelt, Max and Erfurt, Doreen and Ludwig, Horst-Michael}, title = {Quantification of cracks in concrete thin sections considering current methods of image analysis}, series = {Journal of Microscopy}, volume = {2022}, journal = {Journal of Microscopy}, number = {Volume 286, Issue 2}, doi = {10.1111/jmi.13091}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220811-46754}, pages = {154 -- 159}, abstract = {Image analysis is used in this work to quantify cracks in concrete thin sections via modern image processing. Thin sections were impregnated with a yellow epoxy resin, to increase the contrast between voids and other phases of the concrete. By the means of different steps of pre-processing, machine learning and python scripts, cracks can be quantified in an area of up to 40 cm2. As a result, the crack area, lengths and widths were estimated automatically within a single workflow. Crack patterns caused by freeze-thaw damages were investigated. To compare the inner degradation of the investigated thin sections, the crack density was used. Cracks in the thin sections were measured manually in two different ways for validation of the automatic determined results. On the one hand, the presented work shows that the width of cracks can be determined pixelwise, thus providing the plot of a width distribution. On the other hand, the automatically measured crack length differs in comparison to the manually measured ones.}, subject = {Beton}, language = {en} } @article{GuoZhuangChenetal., author = {Guo, Hongwei and Zhuang, Xiaoying and Chen, Pengwan and Alajlan, Naif and Rabczuk, Timon}, title = {Analysis of three-dimensional potential problems in non-homogeneous media with physics-informed deep collocation method using material transfer learning and sensitivity analysis}, series = {Engineering with Computers}, volume = {2022}, journal = {Engineering with Computers}, doi = {10.1007/s00366-022-01633-6}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220811-46764}, pages = {1 -- 22}, abstract = {In this work, we present a deep collocation method (DCM) for three-dimensional potential problems in non-homogeneous media. This approach utilizes a physics-informed neural network with material transfer learning reducing the solution of the non-homogeneous partial differential equations to an optimization problem. We tested different configurations of the physics-informed neural network including smooth activation functions, sampling methods for collocation points generation and combined optimizers. A material transfer learning technique is utilized for non-homogeneous media with different material gradations and parameters, which enhance the generality and robustness of the proposed method. In order to identify the most influential parameters of the network configuration, we carried out a global sensitivity analysis. Finally, we provide a convergence proof of our DCM. The approach is validated through several benchmark problems, also testing different material variations.}, subject = {Deep learning}, language = {en} } @article{ChakrabortyAnitescuZhuangetal., author = {Chakraborty, Ayan and Anitescu, Cosmin and Zhuang, Xiaoying and Rabczuk, Timon}, title = {Domain adaptation based transfer learning approach for solving PDEs on complex geometries}, series = {Engineering with Computers}, volume = {2022}, journal = {Engineering with Computers}, doi = {10.1007/s00366-022-01661-2}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220811-46776}, pages = {1 -- 20}, abstract = {In machine learning, if the training data is independently and identically distributed as the test data then a trained model can make an accurate predictions for new samples of data. Conventional machine learning has a strong dependence on massive amounts of training data which are domain specific to understand their latent patterns. In contrast, Domain adaptation and Transfer learning methods are sub-fields within machine learning that are concerned with solving the inescapable problem of insufficient training data by relaxing the domain dependence hypothesis. In this contribution, this issue has been addressed and by making a novel combination of both the methods we develop a computationally efficient and practical algorithm to solve boundary value problems based on nonlinear partial differential equations. We adopt a meshfree analysis framework to integrate the prevailing geometric modelling techniques based on NURBS and present an enhanced deep collocation approach that also plays an important role in the accuracy of solutions. We start with a brief introduction on how these methods expand upon this framework. We observe an excellent agreement between these methods and have shown that how fine-tuning a pre-trained network to a specialized domain may lead to an outstanding performance compare to the existing ones. As proof of concept, we illustrate the performance of our proposed model on several benchmark problems.}, subject = {Maschinelles Lernen}, language = {en} } @article{RoskammVollmer, author = {Roskamm, Nikolai and Vollmer, Lisa}, title = {Was ist Stadt? Was ist Kritik? Einf{\"u}hrung in die Debatte zum Jubil{\"a}umsheft von sub\urban}, series = {sub\urban. zeitschrift f{\"u}r kritische stadtforschung}, journal = {sub\urban. zeitschrift f{\"u}r kritische stadtforschung}, number = {Band 10, Nr. 1,}, publisher = {Sub\urban e.V.}, address = {Leipzig}, doi = {10.36900/suburban.v10i1.798}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220811-46847}, pages = {127 -- 130}, abstract = {Im Heft zum zehnj{\"a}hrigen Jubil{\"a}um von sub\urban mit dem Themenschwerpunkt „sub\x: Verortungen, Entortungen" ver{\"o}ffentlichen wir eine Debatte, die von den bisherigen in unserer Zeitschrift in dieser Rubrik gef{\"u}hrten textlichen Diskussionen abweicht. Im Vorfeld der Planungen f{\"u}r unsere Jubil{\"a}umsausgabe haben wir die aktuellen Mitglieder unseres wissenschaftlichen Beirats darum gebeten, zwei grundlegende Fragen von kritischer Stadtforschung in kurzen Beitr{\"a}gen zu diskutieren: Was ist Stadt? Was ist Kritik?}, subject = {Stadt}, language = {de} } @article{WelchGuerra, author = {Welch Guerra, Max}, title = {Fach, Gesellschaft und Wissenschaft. Beitrag zur Debatte „Was ist Stadt? Was ist Kritik?"}, series = {sub\urban. zeitschrift f{\"u}r kritische stadtforschung}, volume = {2022}, journal = {sub\urban. zeitschrift f{\"u}r kritische stadtforschung}, number = {Band 10, Nr. 1}, publisher = {Sub\urban e.V.}, address = {Leipzig}, doi = {10.36900/suburban.v10i1.779}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220810-46855}, pages = {188 -- 190}, abstract = {Der Aufruf, die Begriffe Stadt und Kritik in das Zentrum einer Debatte zu stellen, bietet die große Chance, uns weit {\"u}ber begriffliche Kl{\"a}rungen unseres gemeinsamen Arbeitsgegenstands hinaus - die ja auch f{\"u}r sich selbst sehr fruchtbar sein k{\"o}nnen - {\"u}ber die Funktion zu verst{\"a}ndigen, die wir in der Gesellschaft aus{\"u}ben, wenn wir r{\"a}umliche Planung praktizieren, erforschen und lehren. Da in der Bundesrepublik nicht nur ein großer Bedarf, sondern auch eine betr{\"a}chtliche Nachfrage nach {\"o}ffentlicher Planung besteht und die planungsbezogenen Wissenschaften sich eines insgesamt stabilen institutionellen Standes erfreuen, laufen wir Gefahr, die gesellschaftspolitische Legitimation von Berufsfeld und Wissenschaft zu vernachl{\"a}ssigen, sie als gegeben zu behandeln. Wir m{\"u}ssen uns ja kaum rechtfertigen.}, subject = {Stadt}, language = {de} } @article{BecherVoelkerRodehorstetal., author = {Becher, Lia and V{\"o}lker, Conrad and Rodehorst, Volker and Kuhne, Michael}, title = {Background-oriented schlieren technique for two-dimensional visualization of convective indoor air flows}, series = {Optics and Lasers in Engineering}, volume = {2020}, journal = {Optics and Lasers in Engineering}, number = {Volume 134, article 106282}, doi = {https://doi.org/10.1016/j.optlaseng.2020.106282}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220810-46972}, pages = {9}, abstract = {This article focuses on further developments of the background-oriented schlieren (BOS) technique to visualize convective indoor air flow, which is usually defined by very small density gradients. Since the light rays deflect when passing through fluids with different densities, BOS can detect the resulting refractive index gradients as integration along a line of sight. In this paper, the BOS technique is used to yield a two-dimensional visualization of small density gradients. The novelty of the described method is the implementation of a highly sensitive BOS setup to visualize the ascending thermal plume from a heated thermal manikin with temperature differences of minimum 1 K. To guarantee steady boundary conditions, the thermal manikin was seated in a climate laboratory. For the experimental investigations, a high-resolution DLSR camera was used capturing a large field of view with sufficient detail accuracy. Several parameters such as various backgrounds, focal lengths, room air temperatures, and distances between the object of investigation, camera, and structured background were tested to find the most suitable parameters to visualize convective indoor air flow. Besides these measurements, this paper presents the analyzing method using cross-correlation algorithms and finally the results of visualizing the convective indoor air flow with BOS. The highly sensitive BOS setup presented in this article complements the commonly used invasive methods that highly influence weak air flows.}, subject = {Raumklima}, language = {en} } @article{Hanna, author = {Hanna, John}, title = {Computational Modelling for the Effects of Capsular Clustering on Fracture of Encapsulation-Based Self-Healing Concrete Using XFEM and Cohesive Surface Technique}, series = {Applied Sciences}, volume = {2022}, journal = {Applied Sciences}, number = {Volume 12, issue 10, article 5112}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/app12105112}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220721-46717}, pages = {1 -- 17}, abstract = {The fracture of microcapsules is an important issue to release the healing agent for healing the cracks in encapsulation-based self-healing concrete. The capsular clustering generated from the concrete mixing process is considered one of the critical factors in the fracture mechanism. Since there is a lack of studies in the literature regarding this issue, the design of self-healing concrete cannot be made without an appropriate modelling strategy. In this paper, the effects of microcapsule size and clustering on the fractured microcapsules are studied computationally. A simple 2D computational modelling approach is developed based on the eXtended Finite Element Method (XFEM) and cohesive surface technique. The proposed model shows that the microcapsule size and clustering have significant roles in governing the load-carrying capacity and the crack propagation pattern and determines whether the microcapsule will be fractured or debonded from the concrete matrix. The higher the microcapsule circumferential contact length, the higher the load-carrying capacity. When it is lower than 25\% of the microcapsule circumference, it will result in a greater possibility for the debonding of the microcapsule from the concrete. The greater the core/shell ratio (smaller shell thickness), the greater the likelihood of microcapsules being fractured.}, subject = {Beton}, language = {en} } @article{GuerlebeckLegatiukWebber, author = {G{\"u}rlebeck, Klaus and Legatiuk, Dmitrii and Webber, Kemmar}, title = {Operator Calculus Approach to Comparison of Elasticity Models for Modelling of Masonry Structures}, series = {Mathematics}, volume = {2022}, journal = {Mathematics}, number = {Volume 10, issue 10, article 1670}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/math10101670}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220721-46726}, pages = {1 -- 22}, abstract = {The solution of any engineering problem starts with a modelling process aimed at formulating a mathematical model, which must describe the problem under consideration with sufficient precision. Because of heterogeneity of modern engineering applications, mathematical modelling scatters nowadays from incredibly precise micro- and even nano-modelling of materials to macro-modelling, which is more appropriate for practical engineering computations. In the field of masonry structures, a macro-model of the material can be constructed based on various elasticity theories, such as classical elasticity, micropolar elasticity and Cosserat elasticity. Evidently, a different macro-behaviour is expected depending on the specific theory used in the background. Although there have been several theoretical studies of different elasticity theories in recent years, there is still a lack of understanding of how modelling assumptions of different elasticity theories influence the modelling results of masonry structures. Therefore, a rigorous approach to comparison of different three-dimensional elasticity models based on quaternionic operator calculus is proposed in this paper. In this way, three elasticity models are described and spatial boundary value problems for these models are discussed. In particular, explicit representation formulae for their solutions are constructed. After that, by using these representation formulae, explicit estimates for the solutions obtained by different elasticity theories are obtained. Finally, several numerical examples are presented, which indicate a practical difference in the solutions.}, subject = {Mauerwerk}, language = {en} } @article{SoebkeLueck, author = {S{\"o}bke, Heinrich and L{\"u}ck, Andrea}, title = {Framing Algorithm-Driven Development of Sets of Objectives Using Elementary Interactions}, series = {Applied System Innovation}, volume = {2022}, journal = {Applied System Innovation}, number = {Volume 5, issue 3, article 49}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/asi5030049}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220713-46624}, pages = {1 -- 20}, abstract = {Multi-criteria decision analysis (MCDA) is an established methodology to support the decision-making of multi-objective problems. For conducting an MCDA, in most cases, a set of objectives (SOO) is required, which consists of a hierarchical structure comprised of objectives, criteria, and indicators. The development of an SOO is usually based on moderated development processes requiring high organizational and cognitive effort from all stakeholders involved. This article proposes elementary interactions as a key paradigm of an algorithm-driven development process for an SOO that requires little moderation efforts. Elementary interactions are self-contained information requests that may be answered with little cognitive effort. The pairwise comparison of elements in the well-known analytical hierarchical process (AHP) is an example of an elementary interaction. Each elementary interaction in the development process presented contributes to the stepwise development of an SOO. Based on the hypothesis that an SOO may be developed exclusively using elementary interactions (EIs), a concept for a multi-user platform is proposed. Essential components of the platform are a Model Aggregator, an Elementary Interaction Stream Generator, a Participant Manager, and a Discussion Forum. While the latter component serves the professional exchange of the participants, the first three components are intended to be automatable by algorithms. The platform concept proposed has been evaluated partly in an explorative validation study demonstrating the general functionality of the algorithms outlined. In summary, the platform concept suggested demonstrates the potential to ease SOO development processes as the platform concept does not restrict the application domain; it is intended to work with little administration moderation efforts, and it supports the further development of an existing SOO in the event of changes in external conditions. The algorithm-driven development of SOOs proposed in this article may ease the development of MCDA applications and, thus, may have a positive effect on the spread of MCDA applications.}, subject = {Multikriteria-Entscheidung}, language = {en} } @article{DokhanchiArnoldVogeletal.2020, author = {Dokhanchi, Najmeh Sadat and Arnold, J{\"o}rg and Vogel, Albert and V{\"o}lker, Conrad}, title = {Measurement of indoor air temperature distribution using acoustic travel-time tomography: Optimization of transducers location and sound-ray coverage of the room}, series = {Measurement}, volume = {2020}, journal = {Measurement}, number = {Volume 164, article 107934}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.measurement.2020.107934}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220524-46473}, year = {2020}, abstract = {Acoustic travel-time TOMography (ATOM) allows the measurement and reconstruction of air temperature distributions. Due to limiting factors, such as the challenge of travel-time estimation of the early reflections in the room impulse response, which heavily depends on the position of transducers inside the measurement area, ATOM is applied mainly outdoors. To apply ATOM in buildings, this paper presents a numerical solution to optimize the positions of transducers. This optimization avoids reflection overlaps, leading to distinguishable travel-times in the impulse response reflectogram. To increase the accuracy of the measured temperature within tomographic voxels, an additional function is employed to the proposed numerical method to minimize the number of sound-path-free voxels, ensuring the best sound-ray coverage of the room. Subsequently, an experimental set-up has been performed to verify the proposed numerical method. The results indicate the positive impact of the optimal positions of transducers on the distribution of ATOM-temperatures.}, subject = {Bauphysik}, language = {en} } @article{SoebkeLueck, author = {S{\"o}bke, Heinrich and L{\"u}ck, Andrea}, title = {Framing Algorithm-Driven Development of Sets of Objectives Using Elementary Interactions}, series = {Applied System Innovation}, volume = {2022}, journal = {Applied System Innovation}, number = {Volume 5, issue 49, article 49}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/asi503004}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220524-46469}, pages = {1 -- 21}, abstract = {Multi-criteria decision analysis (MCDA) is an established methodology to support the decision-making of multi-objective problems. For conducting an MCDA, in most cases, a set of objectives (SOO) is required, which consists of a hierarchical structure comprised of objectives, criteria, and indicators. The development of an SOO is usually based on moderated development processes requiring high organizational and cognitive effort from all stakeholders involved. This article proposes elementary interactions as a key paradigm of an algorithm-driven development process for an SOO that requires little moderation efforts. Elementary interactions are self-contained information requests that may be answered with little cognitive effort. The pairwise comparison of elements in the well-known analytical hierarchical process (AHP) is an example of an elementary interaction. Each elementary interaction in the development process presented contributes to the stepwise development of an SOO. Based on the hypothesis that an SOO may be developed exclusively using elementary interactions (EIs), a concept for a multi-user platform is proposed. Essential components of the platform are a Model Aggregator, an Elementary Interaction Stream Generator, a Participant Manager, and a Discussion Forum. While the latter component serves the professional exchange of the participants, the first three components are intended to be automatable by algorithms. The platform concept proposed has been evaluated partly in an explorative validation study demonstrating the general functionality of the algorithms outlined. In summary, the platform concept suggested demonstrates the potential to ease SOO development processes as the platform concept does not restrict the application domain; it is intended to work with little administration moderation efforts, and it supports the further development of an existing SOO in the event of changes in external conditions. The algorithm-driven development of SOOs proposed in this article may ease the development of MCDA applications and, thus, may have a positive effect on the spread of MCDA applications.}, subject = {Operations Research}, language = {en} } @article{TarabenMorgenthal, author = {Taraben, Jakob and Morgenthal, Guido}, title = {Integration and Comparison Methods for Multitemporal Image-Based 2D Annotations in Linked 3D Building Documentation}, series = {Remote Sensing}, volume = {2022}, journal = {Remote Sensing}, number = {Volume 14, issue 9, article 2286}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/rs14092286}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220513-46488}, pages = {1 -- 20}, abstract = {Data acquisition systems and methods to capture high-resolution images or reconstruct 3D point clouds of existing structures are an effective way to document their as-is condition. These methods enable a detailed analysis of building surfaces, providing precise 3D representations. However, for the condition assessment and documentation, damages are mainly annotated in 2D representations, such as images, orthophotos, or technical drawings, which do not allow for the application of a 3D workflow or automated comparisons of multitemporal datasets. In the available software for building heritage data management and analysis, a wide range of annotation and evaluation functions are available, but they also lack integrated post-processing methods and systematic workflows. The article presents novel methods developed to facilitate such automated 3D workflows and validates them on a small historic church building in Thuringia, Germany. Post-processing steps using photogrammetric 3D reconstruction data along with imagery were implemented, which show the possibilities of integrating 2D annotations into 3D documentations. Further, the application of voxel-based methods on the dataset enables the evaluation of geometrical changes of multitemporal annotations in different states and the assignment to elements of scans or building models. The proposed workflow also highlights the potential of these methods for condition assessment and planning of restoration work, as well as the possibility to represent the analysis results in standardised building model formats.}, subject = {Bauwesen}, language = {en} } @article{AlsaadHartmannHilbeletal., author = {Alsaad, Hayder and Hartmann, Maria and Hilbel, Rebecca and V{\"o}lker, Conrad}, title = {ENVI-met validation data accompanied with simulation data of the impact of facade greening on the urban microclimate}, series = {Data in Brief}, volume = {2022}, journal = {Data in Brief}, number = {Volume 42, article 108200}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.dib.2022.108200}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220511-46455}, pages = {1 -- 13}, abstract = {This dataset consists mainly of two subsets. The first subset includes measurements and simulation data conducted to validate the simulation tool ENVI-met. The measurements were conducted at the campus of the Bauhaus-University Weimar in Weimar, Germany and consisted of recording exterior air temperature, globe temperature, relative humidity, and wind velocity at 1.5 m at four points on four different days. After the measurements, the geometry of the campus was modelled and meshed; the simulations were conducted using the weather data of the measurements days with the aim of investigating the accuracy of the model. The second data subset consists of ENVI-met simulation data of the potential of facade greening in improving the outdoor environment and the indoor air temperature during heatwaves in Central European cities. The data consist of the boundary conditions and the simulation output of two simulation models: with and without facade greening. The geometry of the models corresponded to a residential buildings district in Stuttgart, Germany. The simulation output consisted of exterior air temperature, mean radiant temperature, relative humidity, and wind velocity at 12 different probe points in the model in addition to the indoor air temperature of an exemplary building. The dataset presents both vertical profiles of the probed parameters as well as the time series output of the five-day simulation duration. Both data subsets correspond to the investigations presented in the co-submitted article [1].}, subject = {Messung}, language = {en} } @article{TeitelbaumAlsaadAvivetal., author = {Teitelbaum, Eric and Alsaad, Hayder and Aviv, Dorit and Kim, Alexander and V{\"o}lker, Conrad and Meggers, Forrest and Pantelic, Jovan}, title = {Addressing a systematic error correcting for free and mixed convection when measuring mean radiant temperature with globe thermometers}, series = {Scientific reports}, volume = {2022}, journal = {Scientific reports}, number = {Volume 12, article 6473}, publisher = {Springer Nature}, address = {London}, doi = {10.1038/s41598-022-10172-5}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220509-46363}, pages = {18}, abstract = {It is widely accepted that most people spend the majority of their lives indoors. Most individuals do not realize that while indoors, roughly half of heat exchange affecting their thermal comfort is in the form of thermal infrared radiation. We show that while researchers have been aware of its thermal comfort significance over the past century, systemic error has crept into the most common evaluation techniques, preventing adequate characterization of the radiant environment. Measuring and characterizing radiant heat transfer is a critical component of both building energy efficiency and occupant thermal comfort and productivity. Globe thermometers are typically used to measure mean radiant temperature (MRT), a commonly used metric for accounting for the radiant effects of an environment at a point in space. In this paper we extend previous field work to a controlled laboratory setting to (1) rigorously demonstrate that existing correction factors used in the American Society of Heating Ventilation and Air-conditioning Engineers (ASHRAE) Standard 55 or ISO7726 for using globe thermometers to quantify MRT are not sufficient; (2) develop a correction to improve the use of globe thermometers to address problems in the current standards; and (3) show that mean radiant temperature measured with ping-pong ball-sized globe thermometers is not reliable due to a stochastic convective bias. We also provide an analysis of the maximum precision of globe sensors themselves, a piece missing from the domain in contemporary literature.}, subject = {Strahlungstemperatur}, language = {en} } @article{KumariHarirchianLahmeretal., author = {Kumari, Vandana and Harirchian, Ehsan and Lahmer, Tom and Rasulzade, Shahla}, title = {Evaluation of Machine Learning and Web-Based Process for Damage Score Estimation of Existing Buildings}, series = {Buildings}, volume = {2022}, journal = {Buildings}, number = {Volume 12, issue 5, article 578}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/buildings12050578}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220509-46387}, pages = {1 -- 23}, abstract = {The seismic vulnerability assessment of existing reinforced concrete (RC) buildings is a significant source of disaster mitigation plans and rescue services. Different countries evolved various Rapid Visual Screening (RVS) techniques and methodologies to deal with the devastating consequences of earthquakes on the structural characteristics of buildings and human casualties. Artificial intelligence (AI) methods, such as machine learning (ML) algorithm-based methods, are increasingly used in various scientific and technical applications. The investigation toward using these techniques in civil engineering applications has shown encouraging results and reduced human intervention, including uncertainties and biased judgment. In this study, several known non-parametric algorithms are investigated toward RVS using a dataset employing different earthquakes. Moreover, the methodology encourages the possibility of examining the buildings' vulnerability based on the factors related to the buildings' importance and exposure. In addition, a web-based application built on Django is introduced. The interface is designed with the idea to ease the seismic vulnerability investigation in real-time. The concept was validated using two case studies, and the achieved results showed the proposed approach's potential efficiency}, subject = {Maschinelles Lernen}, language = {en} } @article{ArtusKoch, author = {Artus, Mathias and Koch, Christian}, title = {State of the art in damage information modeling for RC bridges - A literature review}, series = {Advanced Engineering Informatics}, volume = {2020}, journal = {Advanced Engineering Informatics}, number = {volume 46, article 101171}, publisher = {Elsevier Science}, address = {Amsterdam}, doi = {10.1016/j.aei.2020.101171}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220506-46390}, pages = {1 -- 16}, abstract = {In Germany, bridges have an average age of 40 years. A bridge consumes between 0.4\% and 2\% of its construction cost per year over its entire life cycle. This means that up to 80\% of the construction cost are additionally needed for operation, inspection, maintenance, and destruction. Current practices rely either on paperbased inspections or on abstract specialist software. Every application in the inspection and maintenance sector uses its own data model for structures, inspections, defects, and maintenance. Due to this, data and properties have to be transferred manually, otherwise a converter is necessary for every data exchange between two applications. To overcome this issue, an adequate model standard for inspections, damage, and maintenance is necessary. Modern 3D models may serve as a single source of truth, which has been suggested in the Building Information Modeling (BIM) concept. Further, these models offer a clear visualization of the built infrastructure, and improve not only the planning and construction phases, but also the operation phase of construction projects. BIM is established mostly in the Architecture, Engineering, and Construction (AEC) sector to plan and construct new buildings. Currently, BIM does not cover the whole life cycle of a building, especially not inspection and maintenance. Creating damage models needs the building model first, because a defect is dependent on the building component, its properties and material. Hence, a building information model is necessary to obtain meaningful conclusions from damage information. This paper analyzes the requirements, which arise from practice, and the research that has been done in modeling damage and related information for bridges. With a look at damage categories and use cases related to inspection and maintenance, scientific literature is discussed and synthesized. Finally, research gaps and needs are identified and discussed.}, subject = {Building Information Modeling}, language = {de} } @article{SimonRitz, author = {Simon-Ritz, Frank}, title = {Zwischen Residenzkultur und Bratwursttradition: Th{\"u}ringer UNESCO-Initiativen}, series = {Palmbaum: Literarisches Journal aus Th{\"u}ringen}, volume = {2022}, journal = {Palmbaum: Literarisches Journal aus Th{\"u}ringen}, number = {Heft 1}, publisher = {Quartus Verlag}, address = {Bucha bei Jena}, doi = {10.25643/bauhaus-universitaet.4628}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220413-46282}, pages = {4}, abstract = {Der Essay, der in H. 1/2022 des "Palmbaum: literarisches Journal aus Th{\"u}ringen" erschienen ist, besch{\"a}ftigt sich mit dem Begriff des "kulturellen Erbes", der verschiedenen UNESCO-Programmen zugrundeliegt.}, subject = {Kultur}, language = {de} } @article{ArtusAlabassyKoch, author = {Artus, Mathias and Alabassy, Mohamed Said Helmy and Koch, Christian}, title = {A BIM Based Framework for Damage Segmentation, Modeling, and Visualization Using IFC}, series = {Applied Sciences}, volume = {2022}, journal = {Applied Sciences}, number = {volume 12, issue 6, article 2772}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/app12062772}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220314-46059}, pages = {1 -- 24}, abstract = {Paper-based data acquisition and manual transfer between incompatible software or data formats during inspections of bridges, as done currently, are time-consuming, error-prone, cumbersome, and lead to information loss. A fully digitized workflow using open data formats would reduce data loss, efforts, and the costs of future inspections. On the one hand, existing studies proposed methods to automatize data acquisition and visualization for inspections. These studies lack an open standard to make the gathered data available for other processes. On the other hand, several studies discuss data structures for exchanging damage information among different stakeholders. However, those studies do not cover the process of automatic data acquisition and transfer. This study focuses on a framework that incorporates automatic damage data acquisition, transfer, and a damage information model for data exchange. This enables inspectors to use damage data for subsequent analyses and simulations. The proposed framework shows the potentials for a comprehensive damage information model and related (semi-)automatic data acquisition and processing.}, subject = {Building Information Modeling}, language = {en} } @article{ZhangRen, author = {Zhang, Yongzheng and Ren, Huilong}, title = {Implicit implementation of the nonlocal operator method: an open source code}, series = {Engineering with computers}, volume = {2022}, journal = {Engineering with computers}, publisher = {Springer}, address = {London}, doi = {10.1007/s00366-021-01537-x}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220216-45930}, pages = {1 -- 35}, abstract = {In this paper, we present an open-source code for the first-order and higher-order nonlocal operator method (NOM) including a detailed description of the implementation. The NOM is based on so-called support, dual-support, nonlocal operators, and an operate energy functional ensuring stability. The nonlocal operator is a generalization of the conventional differential operators. Combined with the method of weighed residuals and variational principles, NOM establishes the residual and tangent stiffness matrix of operate energy functional through some simple matrix without the need of shape functions as in other classical computational methods such as FEM. NOM only requires the definition of the energy drastically simplifying its implementation. The implementation in this paper is focused on linear elastic solids for sake of conciseness through the NOM can handle more complex nonlinear problems. The NOM can be very flexible and efficient to solve partial differential equations (PDEs), it's also quite easy for readers to use the NOM and extend it to solve other complicated physical phenomena described by one or a set of PDEs. Finally, we present some classical benchmark problems including the classical cantilever beam and plate-with-a-hole problem, and we also make an extension of this method to solve complicated problems including phase-field fracture modeling and gradient elasticity material.}, subject = {Strukturmechanik}, language = {en} } @article{MehlingSchnabelLondong, author = {Mehling, Simon and Schnabel, Tobias and Londong, J{\"o}rg}, title = {Photocatalytic ozonation in an immersion rotary body reactor for the removal of micro-pollutants from the effluent of wastewater treatment plants}, series = {Water Science \& Technology}, volume = {2022}, journal = {Water Science \& Technology}, number = {volume 85, issue 1}, publisher = {IWA Publishing}, address = {London}, doi = {10.2166/wst.2021.617}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220209-45865}, pages = {535 -- 548}, abstract = {Carrier-bound titanium dioxide catalysts were used in a photocatalytic ozonation reactor for the degradation of micro-pollutants in real wastewater. A photocatalytic immersion rotary body reactor with a 36-cm disk diameter was used, and was irradiated using UV-A light-emitting diodes. The rotating disks were covered with catalysts based on stainless steel grids coated with titanium dioxide. The dosing of ozone was carried out through the liquid phase via an external enrichment and a supply system transverse to the flow direction. The influence of irradiation power and ozone dose on the degradation rate for photocatalytic ozonation was investigated. In addition, the performance of the individual processes photocatalysis and ozonation were studied. The degradation kinetics of the parent compounds were determined using liquid chromatography tandem mass spectrometry. First-order kinetics were determined for photocatalysis and photocatalytic ozonation. A maximum reaction rate of the reactor was determined, which could be achieved by both photocatalysis and photocatalytic ozonation. At a dosage of 0.4 mg /mg DOC, the maximum reaction rate could be achieved using 75\% of the irradiation power used for sole photocatalysis, allowing increases in the energetic efficiency of photocatalytic wastewater treatment processes. The process of photocatalytic ozonation is suitable to remove a wide spectrum of micro-pollutants from wastewater.}, subject = {Abwasserreinigung}, language = {en} } @article{Zhang, author = {Zhang, Yongzheng}, title = {Nonlocal dynamic Kirchhoff plate formulation based on nonlocal operator method}, series = {Engineering with Computers}, volume = {2022}, journal = {Engineering with Computers}, publisher = {Springer}, address = {London}, doi = {10.1007/s00366-021-01587-1}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220209-45849}, pages = {1 -- 35}, abstract = {In this study, we propose a nonlocal operator method (NOM) for the dynamic analysis of (thin) Kirchhoff plates. The nonlocal Hessian operator is derived based on a second-order Taylor series expansion. The NOM does not require any shape functions and associated derivatives as 'classical' approaches such as FEM, drastically facilitating the implementation. Furthermore, NOM is higher order continuous, which is exploited for thin plate analysis that requires C1 continuity. The nonlocal dynamic governing formulation and operator energy functional for Kirchhoff plates are derived from a variational principle. The Verlet-velocity algorithm is used for the time discretization. After confirming the accuracy of the nonlocal Hessian operator, several numerical examples are simulated by the nonlocal dynamic Kirchhoff plate formulation.}, subject = {Angewandte Mathematik}, language = {en} } @article{RabczukGuoZhuangetal., author = {Rabczuk, Timon and Guo, Hongwei and Zhuang, Xiaoying and Chen, Pengwan and Alajlan, Naif}, title = {Stochastic deep collocation method based on neural architecture search and transfer learning for heterogeneous porous media}, series = {Engineering with Computers}, volume = {2022}, journal = {Engineering with Computers}, publisher = {Springer}, address = {London}, doi = {10.1007/s00366-021-01586-2}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220209-45835}, pages = {1 -- 26}, abstract = {We present a stochastic deep collocation method (DCM) based on neural architecture search (NAS) and transfer learning for heterogeneous porous media. We first carry out a sensitivity analysis to determine the key hyper-parameters of the network to reduce the search space and subsequently employ hyper-parameter optimization to finally obtain the parameter values. The presented NAS based DCM also saves the weights and biases of the most favorable architectures, which is then used in the fine-tuning process. We also employ transfer learning techniques to drastically reduce the computational cost. The presented DCM is then applied to the stochastic analysis of heterogeneous porous material. Therefore, a three dimensional stochastic flow model is built providing a benchmark to the simulation of groundwater flow in highly heterogeneous aquifers. The performance of the presented NAS based DCM is verified in different dimensions using the method of manufactured solutions. We show that it significantly outperforms finite difference methods in both accuracy and computational cost.}, subject = {Maschinelles Lernen}, language = {en} } @article{LegatiukGuerlebeckHommel, author = {Legatiuk, Anastasiia and G{\"u}rlebeck, Klaus and Hommel, Angela}, title = {Estimates for the discrete fundamental solution of the discrete Laplace operator on a rectangular lattice}, series = {Mathematical Methods in the Applied Sciences}, volume = {2021}, journal = {Mathematical Methods in the Applied Sciences}, publisher = {Wiley}, address = {Chichester}, doi = {10.1002/mma.7747}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220209-45829}, pages = {1 -- 23}, abstract = {This paper presents numerical analysis of the discrete fundamental solution of the discrete Laplace operator on a rectangular lattice. Additionally, to provide estimates in interior and exterior domains, two different regularisations of the discrete fundamental solution are considered. Estimates for the absolute difference and lp-estimates are constructed for both regularisations. Thus, this work extends the classical results in the discrete potential theory to the case of a rectangular lattice and serves as a basis for future convergence analysis of the method of discrete potentials on rectangular lattices.}, subject = {diskrete Fourier-Transformation}, language = {en} } @article{BecherGenaAlsaadetal., author = {Becher, Lia and Gena, Amayu Wakoya and Alsaad, Hayder and Richter, Bernhard and Spahn, Claudia and V{\"o}lker, Conrad}, title = {The spread of breathing air from wind instruments and singers using schlieren techniques}, series = {Indoor Air}, volume = {2021}, journal = {Indoor Air}, number = {volume 31, issue 6}, publisher = {Wiley Blackwell}, address = {Oxford}, doi = {10.1111/ina.12869}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220209-45817}, pages = {1798 -- 1814}, abstract = {The spread of breathing air when playing wind instruments and singing was investigated and visualized using two methods: (1) schlieren imaging with a schlieren mirror and (2) background-oriented schlieren (BOS). These methods visualize airflow by visualizing density gradients in transparent media. The playing of professional woodwind and brass instrument players, as well as professional classical trained singers were investigated to estimate the spread distances of the breathing air. For a better comparison and consistent measurement series, a single high note, a single low note, and an extract of a musical piece were investigated. Additionally, anemometry was used to determine the velocity of the spreading breathing air and the extent to which it was quantifiable. The results showed that the ejected airflow from the examined instruments and singers did not exceed a spreading range of 1.2 m into the room. However, differences in the various instruments have to be considered to assess properly the spread of the breathing air. The findings discussed below help to estimate the risk of cross-infection for wind instrument players and singers and to develop efficacious safety precautions, which is essential during critical health periods such as the current COVID-19 pandemic.}, subject = {Covid-19}, language = {en} } @article{BuschowSuhrSerger, author = {Buschow, Christopher and Suhr, Maike and Serger, Hauke}, title = {Media Work as Field Advancement: The Case of Science Media Center Germany}, series = {Media and Communication}, volume = {2022}, journal = {Media and Communication}, number = {Volume 10, issue 1}, publisher = {Cogitatio Press}, address = {Lisbon}, doi = {10.17645/mac.v10i1.4454}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220125-45709}, pages = {99 -- 109}, abstract = {In the wake of the news industry's digitization, novel organizations that differ considerably from traditional media firms in terms of their functional roles and organizational practices of media work are emerging. One new type is the field repair organization, which is characterized by supporting high-quality media work to compensate for the deficits (such as those which come from cost savings and layoffs) which have become apparent in legacy media today. From a practice-theoretical research perspective and based on semi-structured interviews, virtual field observations, and document analysis, we have conducted a single case study on Science Media Center Germany (SMC), a unique non-profit news start-up launched in 2016 in Cologne, Germany. Our findings show that, in addition to field repair activities, SMC aims to facilitate progress and innovation in the field, which we refer to as field advancement. This helps to uncover emerging needs and anticipates problems before they intensify or even occur, proactively providing products and tools for future journalism. This article contributes to our understanding of novel media organizations with distinct functions in the news industry, allowing for advancements in theory on media work and the organization of journalism in times of digital upheaval.}, subject = {Journalismus}, language = {en} } @article{KrausCrişanWittor, author = {Kraus, Matthias and Cri{\c{s}}an, Nicolae-Andrei and Wittor, Bj{\"o}rn}, title = {Stability Study of Cantilever-Beams - Numerical Analysis and Analytical Calculation (LTB)}, series = {ce/papers}, volume = {2021}, journal = {ce/papers}, number = {Volume 4, issue 2-4}, publisher = {Ernst \& Sohn, a Wiley brand}, address = {Berlin}, doi = {10.1002/cepa.1539}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45637}, pages = {2199 -- 2206}, abstract = {According to Eurocode, the computation of bending strength for steel cantilever beams is a straightforward process. The approach is based on an Ayrton-Perry formula adaptation of buckling curves for steel members in compression, which involves the computation of an elastic critical buckling load for considering the instability. NCCI documents offer a simplified formula to determine the critical bending moment for cantilevers beams with symmetric cross-section. Besides the NCCI recommendations, other approaches, e.g. research literature or Finite-Element-Analysis, may be employed to determine critical buckling loads. However, in certain cases they render different results. Present paper summarizes and compares the abovementioned analytical and numerical approaches for determining critical loads and it exemplarily analyses corresponding cantilever beam capacities using numerical approaches based on plastic zones theory (GMNIA).}, subject = {Tr{\"a}ger}, language = {en} } @article{IbanezKraus, author = {Ibanez, Stalin and Kraus, Matthias}, title = {A Numerical Approach for Plastic Cross Cross-Sectional Analyses of Steel Members}, series = {ce/papers}, volume = {2021}, journal = {ce/papers}, number = {Volume 4, issue 2-4}, publisher = {Ernst \& Sohn, a Wiley brand}, address = {Berlin}, doi = {10.1002/cepa.1527}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45622}, pages = {2098 -- 2106}, abstract = {Global structural analyses in civil engineering are usually performed considering linear-elastic material behavior. However, for steel structures, a certain degree of plasticization depending on the member classification may be considered. Corresponding plastic analyses taking material nonlinearities into account are effectively realized using numerical methods. Frequently applied finite elements of two and three-dimensional models evaluate the plasticity at defined nodes using a yield surface, i.e. by a yield condition, hardening rule, and flow rule. Corresponding calculations are connected to a large numerical as well as time-consuming effort and they do not rely on the theoretical background of beam theory, to which the regulations of standards mainly correspond. For that reason, methods using beam elements (one-dimensional) combined with cross-sectional analyses are commonly applied for steel members in terms of plastic zones theories. In these approaches, plasticization is in general assessed by means of axial stress only. In this paper, more precise numerical representation of the combined stress states, i.e. axial and shear stresses, is presented and results of the proposed approach are validated and discussed.}, subject = {Stahlkonstruktion}, language = {en} } @article{MullisSchipper, author = {Mullis, Daniel and Schipper, Sebastian}, title = {Die postdemokratische Stadt zwischen Politisierung und Kontinuit{\"a}t. Oder ist die Stadt jemals demokratisch gewesen?}, series = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, volume = {2013}, journal = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, number = {Band 1, Heft 2}, publisher = {sub\urban e.V.}, address = {Berlin}, doi = {10.36900/suburban.v1i2.97}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45600}, pages = {79 -- 100}, abstract = {In der kritischen Stadtforschung wird die These der postdemokratischen Stadt aktuell immer wieder aufgegriffen und dabei eng mit Prozessen der Neoliberalisierung verkn{\"u}pft. Ausgehend von einer kritischen Diskussion der konzeptionellen Zug{\"a}nge bei Colin Crouch und Jacques Ranci{\`e}re geht der Beitrag anhand der Geschichte der kommunalen Selbstverwaltung in Frankfurt am Main dem Gehalt der beiden Begriffsbestimmungen in der konkreten historischen Analyse nach. Verwiesen wird dabei auf die unterschiedliche Analysetiefe der beiden Konzepte. Entgegen der bei Crouch vorherrschenden Annahme, dass es vor der neoliberalen Stadt eine demokratische Form st{\"a}dtischen Regierens gegeben hat, wird unter R{\"u}ckbezug auf die Argumentation Ranci{\`e}res zur Demokratie betont, dass der Fordismus keinesfalls als egalit{\"a}rer, inklusiver oder demokratischer charakterisiert werden kann. Vielmehr vertreten wir die These, dass die fordistische Stadt zwar aus anderen Gr{\"u}nden, aber vom Grundsatz her nicht weniger postdemokratisch gewesen ist als die neoliberale der Gegenwart und dass die demokratischen Momente am ehesten in den Br{\"u}chen und Spalten der sozialen Konflikte der 1970er und 1980er Jahre gefunden werden k{\"o}nnen.}, subject = {Stadtplanung}, language = {de} } @article{Birkholz, author = {Birkholz, Marie Luise}, title = {M{\"a}chtiger Boden. Essay {\"u}ber den Versuch, einen Staatsapparat zu erlaufen}, series = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, volume = {2015}, journal = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, number = {Band 3, Heft 2}, publisher = {ub\urban e.V.}, address = {Berlin}, doi = {10.36900/suburban.v3i2.200}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45591}, pages = {141 -- 154}, abstract = {Der Text folgt in essayistischer Form einem Spaziergang durch das politische Zentrum Bras{\´i}lias in Brasilien. Die Konzentration liegt auf der Gestaltung des Bodens. Wie ist die Planhauptstadt „vom Reißbrett" in der Horizontalen gestaltet? Wie sehen repr{\"a}sentative Pl{\"a}tze einer Stadt aus, die vor allem f{\"u}r Autos gebaut worden ist? Der forschende Blick liegt auf dem erlebten Ist-Zustand und wird assoziativ mit Ergebnissen der Forschungsarbeit aus Deutschland reflektiert. „M{\"a}chtiger Boden" entstand als Satellit zur aktuellen Forschung der Autorin im Rahmen eines Aufenthalts in Brasilien.}, subject = {Brasilia}, language = {de} } @article{SchmidtLahmer, author = {Schmidt, Albrecht and Lahmer, Tom}, title = {Efficient domain decomposition based reliability analysis for polymorphic uncertain material parameters}, series = {Proceedings in Applied Mathematics \& Mechanics}, volume = {2021}, journal = {Proceedings in Applied Mathematics \& Mechanics}, number = {Volume 21, issue 1}, publisher = {Wiley-VHC}, address = {Weinheim}, doi = {10.1002/pamm.202100014}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45563}, pages = {1 -- 4}, abstract = {Realistic uncertainty description incorporating aleatoric and epistemic uncertainties can be described within the framework of polymorphic uncertainty, which is computationally demanding. Utilizing a domain decomposition approach for random field based uncertainty models the proposed level-based sampling method can reduce these computational costs significantly and shows good agreement with a standard sampling technique. While 2-level configurations tend to get unstable with decreasing sampling density 3-level setups show encouraging results for the investigated reliability analysis of a structural unit square.}, subject = {Polymorphie}, language = {en} } @article{KrausKlausWittor, author = {Kraus, Matthias and Klaus, Martin and Wittor, Bj{\"o}rn}, title = {Experimental Analyses on the Resistance of Tapped Blind Holes}, series = {ce/papers}, volume = {2021}, journal = {ce/papers}, number = {Volume 4, issue 2-4}, publisher = {Ernst \& Sohn, a Wiley brand}, address = {Berlin}, doi = {10.1002/cepa.1273}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45553}, pages = {141 -- 147}, abstract = {Bolted connections are commonly used in steel construction. The load-bearing behavior of bolt fittings has extensively been studied in various research activities and the bearing capacity of bolted connections can be assessed well by standard regulations for practical applications. With regard to tensile loading, the nut does not have strong influence on resistances, since the failure occurs in the bolts due to higher material strengths of the nuts. In some applications, so-called "blind holes" are used to connect plated components. In a manner of speaking, the nut is replaced by the "outer" plate with a prefabricated hole and thread, in which the bolt can be screwed and tightened. In such connections, the limit load capacity cannot solely be assessed by the bolt resistance, since the threaded hole in the base material has strong influence on the structural behavior. In this context, the available screw-in depth of the blind hole is of fundamental importance. The German National Annex of EN 1993-1-8 provides information on a necessary depth in order to transfer the full tensile capacity of the bolt. However, some connections do not allow to fabricate such depths. In these cases, the capacity of the connection is unclear and not specified. In this paper, first experiments on corresponding connections with different screw-in depths are presented and compared to limit load capacities according to the standard.}, subject = {Gewinde}, language = {en} } @article{MeiabadiMoradiKaramimoghadametal., author = {Meiabadi, Mohammad Saleh and Moradi, Mahmoud and Karamimoghadam, Mojtaba and Ardabili, Sina and Bodaghi, Mahdi and Shokri, Manouchehr and Mosavi, Amir Hosein}, title = {Modeling the Producibility of 3D Printing in Polylactic Acid Using Artificial Neural Networks and Fused Filament Fabrication}, series = {polymers}, volume = {2021}, journal = {polymers}, number = {Volume 13, issue 19, article 3219}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/polym13193219}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220110-45518}, pages = {1 -- 21}, abstract = {Polylactic acid (PLA) is a highly applicable material that is used in 3D printers due to some significant features such as its deformation property and affordable cost. For improvement of the end-use quality, it is of significant importance to enhance the quality of fused filament fabrication (FFF)-printed objects in PLA. The purpose of this investigation was to boost toughness and to reduce the production cost of the FFF-printed tensile test samples with the desired part thickness. To remove the need for numerous and idle printing samples, the response surface method (RSM) was used. Statistical analysis was performed to deal with this concern by considering extruder temperature (ET), infill percentage (IP), and layer thickness (LT) as controlled factors. The artificial intelligence method of artificial neural network (ANN) and ANN-genetic algorithm (ANN-GA) were further developed to estimate the toughness, part thickness, and production-cost-dependent variables. Results were evaluated by correlation coefficient and RMSE values. According to the modeling results, ANN-GA as a hybrid machine learning (ML) technique could enhance the accuracy of modeling by about 7.5, 11.5, and 4.5\% for toughness, part thickness, and production cost, respectively, in comparison with those for the single ANN method. On the other hand, the optimization results confirm that the optimized specimen is cost-effective and able to comparatively undergo deformation, which enables the usability of printed PLA objects.}, subject = {3D-Druck}, language = {en} } @article{AlsaadHartmannVoelker, author = {Alsaad, Hayder and Hartmann, Maria and V{\"o}lker, Conrad}, title = {Hygrothermal simulation data of a living wall system for decentralized greywater treatment}, series = {Data in Brief}, volume = {2022}, journal = {Data in Brief}, number = {volume 40, article 107741}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.dib.2021.107741}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220106-45483}, pages = {12}, abstract = {This dataset presents the numerical analysis of the heat and moisture transport through a facade equipped with a living wall system designated for greywater treatment. While such greening systems provide many environmental benefits, they involve pumping large quantities of water onto the wall assembly, which can increase the risk of moisture in the wall as well as impaired energetic performance due to increased thermal conductivity with increased moisture content in the building materials. This dataset was acquired through numerical simulation using the coupling of two simulation tools, namely Envi-Met and Delphin. This coupling was used to include the complex role the plants play in shaping the near-wall environmental parameters in the hygrothermal simulations. Four different wall assemblies were investigated, each assembly was assessed twice: with and without the living wall. The presented data include the input and output parameters of the simulations, which were presented in the co-submitted article [1].}, subject = {Kupplung}, language = {en} } @article{KleinerRoesslerVogtetal., author = {Kleiner, Florian and R{\"o}ßler, Christiane and Vogt, Franziska and Osburg, Andrea and Ludwig, Horst-Michael}, title = {Reconstruction of calcium silicate hydrates using multiple 2D and 3D imaging techniques: Light microscopy, μ-CT, SEM, FIB-nT combined with EDX}, series = {Journal of Microscopy}, volume = {2021}, journal = {Journal of Microscopy}, publisher = {John Wiley \& Sons Ltd}, address = {Oxford}, doi = {10.1111/jmi.13081}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220106-45458}, pages = {1 -- 6}, abstract = {This study demonstrates the application and combination of multiple imaging techniques [light microscopy, micro-X-ray computer tomography (μ-CT), scanning electron microscopy (SEM) and focussed ion beam - nano-tomography (FIB-nT)] to the analysis of the microstructure of hydrated alite across multiple scales. However, by comparing findings with mercury intrusion porosimetry (MIP), it becomes obvious that the imaged 3D volumes and 2D images do not sufficiently overlap at certain scales to allow a continuous quantification of the pore size distribution (PSD). This can be overcome by improving the resolution and increasing the measured volume. Furthermore, results show that the fibrous morphology of calcium-silicate-hydrates (C-S-H) phases is preserved during FIB-nT. This is a requirement for characterisation of nano-scale porosity. Finally, it was proven that the combination of FIB-nT with energy-dispersive X-ray spectroscopy (EDX) data facilitates the phase segmentation of a 11 × 11 × 7.7 μm3 volume of hydrated alite.}, subject = {Zementklinker}, language = {en} } @article{JiangRoesslerWellmannetal., author = {Jiang, Mingze and R{\"o}ßler, Christiane and Wellmann, Eva and Klaver, Jop and Kleiner, Florian and Schmatz, Joyce}, title = {Workflow for high-resolution phase segmentation of cement clinker fromcombined BSE image and EDX spectral data}, series = {Journal of Microscopy}, volume = {2021}, journal = {Journal of Microscopy}, publisher = {Wiley-Blackwell}, address = {Oxford}, doi = {10.1111/jmi.13072}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211215-45449}, pages = {1 -- 7}, abstract = {Burning of clinker is the most influencing step of cement quality during the production process. Appropriate characterisation for quality control and decision-making is therefore the critical point to maintain a stable production but also for the development of alternative cements. Scanning electron microscopy (SEM) in combination with energy dispersive X-ray spectroscopy (EDX) delivers spatially resolved phase and chemical information for cement clinker. This data can be used to quantify phase fractions and chemical composition of identified phases. The contribution aims to provide an overview of phase fraction quantification by semi-automatic phase segmentation using high-resolution backscattered electron (BSE) images and lower-resolved EDX element maps. Therefore, a tool for image analysis was developed that uses state-of-the-art algorithms for pixel-wise image segmentation and labelling in combination with a decision tree that allows searching for specific clinker phases. Results show that this tool can be applied to segment sub-micron scale clinker phases and to get a quantification of all phase fractions. In addition, statistical evaluation of the data is implemented within the tool to reveal whether the imaged area is representative for all clinker phases.}, subject = {Zementklinker}, language = {en} } @article{Wenzel, author = {Wenzel, Mirjam}, title = {Das partikulare Ged{\"a}chtnis j{\"u}discher Museen}, doi = {10.25643/bauhaus-universitaet.4535}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211129-45355}, pages = {24}, abstract = {Bauhaus-Gastprofessorin Mirjam Wenzel referierte am 30. Juni 2021 im Audimax der Bauhaus-Universit{\"a}t Weimar zur Entstehungsgeschichte und Konzeption J{\"u}discher Museen. Dabei ging sie darauf ein, inwiefern diese Museen besonders relevant f{\"u}r aktuelle gesellschaftliche und politische Fragestellungen sind. Prof. Wenzels zweiter {\"o}ffentlicher Vortrag an der Bauhaus-Universit{\"a}t Weimar skizzierte die Potentiale von Kultureinrichtungen in Zeiten gesellschaftspolitischer Ver{\"a}nderungen im Allgemeinen und die Bedeutung J{\"u}discher Museen angesichts verbaler und t{\"a}tlicher Gewalt gegen J{\"u}dinnen und Juden im Besonderen.}, subject = {Ged{\"a}chtnis}, language = {de} } @article{Schwerzmann, author = {Schwerzmann, Katia}, title = {Abolish! Against the Use of Risk Assessment Algorithms at Sentencing in the US Criminal Justice System}, series = {Philosophy \& Technology}, volume = {2021}, journal = {Philosophy \& Technology}, doi = {10.1007/s13347-021-00491-2}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211207-45417}, pages = {1 -- 22}, abstract = {In this article, I show why it is necessary to abolish the use of predictive algorithms in the US criminal justice system at sentencing. After presenting the functioning of these algorithms in their context of emergence, I offer three arguments to demonstrate why their abolition is imperative. First, I show that sentencing based on predictive algorithms induces a process of rewriting the temporality of the judged individual, flattening their life into a present inescapably doomed by its past. Second, I demonstrate that recursive processes, comprising predictive algorithms and the decisions based on their predictions, systematically suppress outliers and progressively transform reality to match predictions. In my third and final argument, I show that decisions made on the basis of predictive algorithms actively perform a biopolitical understanding of justice as management and modulation of risks. In such a framework, justice becomes a means to maintain a perverse social homeostasis that systematically exposes disenfranchised Black and Brown populations to risk.}, subject = {Biopolitik}, language = {en} } @article{SchmitzKraft, author = {Schmitz, Tonia and Kraft, Eckhard}, title = {Pilot scale photobioreactor system for land-based macroalgae cultivation}, series = {Journal of Applied Phycology}, volume = {2021}, journal = {Journal of Applied Phycology}, doi = {10.1007/s10811-021-02617-7}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211207-45401}, pages = {1 -- 10}, abstract = {Marine macroalgae such as Ulva intestinalis have promising properties as feedstock for cosmetics and pharmaceuticals. However, since the quantity and quality of naturally grown algae vary widely, their exploitability is reduced - especially for producers in high-priced markets. Moreover, the expansion of marine or shore-based cultivation systems is unlikely in Europe, since promising sites either lie in fishing zones, recreational areas, or natural reserves. The aim was therefore to develop a closed photobioreactor system enabling full control of abiotic environmental parameters and an effective reconditioning of the cultivation medium in order to produce marine macroalgae at sites distant from the shore. To assess the feasibility and functionality of the chosen technological concept, a prototypal plant has been implemented in central Germany - a site distant from the sea. Using a newly developed, submersible LED light source, cultivation experiments with Ulva intestinalis led to growth rates of 7.72 ± 0.04 \% day-1 in a cultivation cycle of 28 days. Based on the space demand of the production system, this results in fresh mass productivity of 3.0 kg m-2, respectively, of 1.1 kg m-2 per year. Also considering the ratio of biomass to energy input amounting to 2.76 g kWh-1, significant future improvements of the developed photobioreactor system should include the optimization of growth parameters, and the reduction of the system's overall energy demand.}, subject = {Makroalgen}, language = {en} } @article{MuellerLudwigTangeHasholt, author = {M{\"u}ller, Matthias and Ludwig, Horst-Michael and Tange Hasholt, Marianne}, title = {Salt frost attack on concrete: the combined effect of cryogenic suction and chloride binding on ice formation}, series = {Materials and Structures}, volume = {2021}, journal = {Materials and Structures}, number = {issue 54, article 189}, doi = {10.1617/s11527-021-01779-7}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211207-45392}, pages = {1 -- 16}, abstract = {Scaling of concrete due to salt frost attack is an important durability issue in moderate and cold climates. The actual damage mechanism is still not completely understood. Two recent damage theories—the glue spall theory and the cryogenic suction theory—offer plausible, but conflicting explanations for the salt frost scaling mechanism. The present study deals with the cryogenic suction theory, which assumes that freezing concrete can take up unfrozen brine from a partly frozen deicing solution during salt frost attack. According to the model hypothesis, the resulting saturation of the concrete surface layer intensifies the ice formation in this layer and causes salt frost scaling. In this study an experimental technique was developed that makes it possible to quantify to which extent brine uptake can increase ice formation in hardened cement paste (used as a model material for concrete). The experiments were carried out with low temperature differential scanning calorimetry, where specimens were subjected to freeze-thaw cycles while being in contact with NaCl brine. Results showed that the ice content in the specimens increased with subsequent freeze-thaw cycles due to the brine uptake at temperatures below 0 °C. The ability of the hardened cement paste to bind chlorides from the absorbed brine at the same time affected the freezing/melting behavior of the pore solution and the magnitude of the ice content.}, subject = {Beton}, language = {en} } @article{RenZhuangOterkusetal., author = {Ren, Huilong and Zhuang, Xiaoying and Oterkus, Erkan and Zhu, Hehua and Rabczuk, Timon}, title = {Nonlocal strong forms of thin plate, gradient elasticity, magneto-electro-elasticity and phase-field fracture by nonlocal operator method}, series = {Engineering with Computers}, volume = {2021}, journal = {Engineering with Computers}, doi = {10.1007/s00366-021-01502-8}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211207-45388}, pages = {1 -- 22}, abstract = {The derivation of nonlocal strong forms for many physical problems remains cumbersome in traditional methods. In this paper, we apply the variational principle/weighted residual method based on nonlocal operator method for the derivation of nonlocal forms for elasticity, thin plate, gradient elasticity, electro-magneto-elasticity and phase-field fracture method. The nonlocal governing equations are expressed as an integral form on support and dual-support. The first example shows that the nonlocal elasticity has the same form as dual-horizon non-ordinary state-based peridynamics. The derivation is simple and general and it can convert efficiently many local physical models into their corresponding nonlocal forms. In addition, a criterion based on the instability of the nonlocal gradient is proposed for the fracture modelling in linear elasticity. Several numerical examples are presented to validate nonlocal elasticity and the nonlocal thin plate.}, subject = {Bruchmechanik}, language = {en} } @article{AnicPenavaSarhosisetal., author = {Anic, Filip and Penava, Davorin and Sarhosis, Vasilis and Abrahamczyk, Lars}, title = {Development and Calibration of a 3D Micromodel for Evaluation of Masonry Infilled RC Frame Structural Vulnerability to Earthquakes}, series = {Geosciences}, volume = {2021}, journal = {Geosciences}, number = {Voume 11, issue 11, article 468}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/geosciences11110468}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211202-45370}, pages = {23}, abstract = {Within the scope of literature, the influence of openings within the infill walls that are bounded by a reinforced concrete frame and excited by seismic drift forces in both in- and out-of-plane direction is still uncharted. Therefore, a 3D micromodel was developed and calibrated thereafter, to gain more insight in the topic. The micromodels were calibrated against their equivalent physical test specimens of in-plane, out-of-plane drift driven tests on frames with and without infill walls and openings, as well as out-of-plane bend test of masonry walls. Micromodels were rectified based on their behavior and damage states. As a result of the calibration process, it was found that micromodels were sensitive and insensitive to various parameters, regarding the model's behavior and computational stability. It was found that, even within the same material model, some parameters had more effects when attributed to concrete rather than on masonry. Generally, the in-plane behavior of infilled frames was found to be largely governed by the interface material model. The out-of-plane masonry wall simulations were governed by the tensile strength of both the interface and masonry material model. Yet, the out-of-plane drift driven test was governed by the concrete material properties.}, subject = {Verwundbarkeit}, language = {en} } @article{LondongBarthSoebke, author = {Londong, J{\"o}rg and Barth, Marcus and S{\"o}bke, Heinrich}, title = {Modeling and Simulation of Source Separation in Sanitation Systems for Reducing Emissions of Antimicrobial Resistances}, series = {Water}, volume = {2021}, journal = {Water}, number = {Volume 13, issue 23, article 3342}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/w13233342}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211202-45338}, pages = {1 -- 19}, abstract = {Antimicrobial resistance (AMR) is identified by the World Health Organization (WHO) as one of the top ten threats to public health worldwide. In addition to public health, AMR also poses a major threat to food security and economic development. Current sanitation systems contribute to the emergence and spread of AMR and lack effective AMR mitigation measures. This study assesses source separation of blackwater as a mitigation measure against AMR. A source-separation-modified combined sanitation system with separate collection of blackwater and graywater is conceptually described. Measures taken at the source, such as the separate collection and discharge of material flows, were not considered so far on a load balance basis, i.e., they have not yet been evaluated for their effectiveness. The sanitation system described is compared with a combined system and a separate system regarding AMR emissions by means of simulation. AMR is represented in the simulation model by one proxy parameter each for antibiotics (sulfamethoxa-zole), antibiotic-resistant bacteria (extended-spectrum beta-lactamase E. Coli), and antibiotic re-sistance genes (blaTEM). The simulation results suggest that the source-separation-based sanitation system reduces emissions of antibiotic-resistant bacteria and antibiotic resistance genes into the aquatic environment by more than six logarithm steps compared to combined systems. Sulfa-methoxazole emissions can be reduced by 75.5\% by keeping blackwater separate from graywater and treating it sufficiently. In summary, sanitation systems incorporating source separation are, to date, among the most effective means of preventing the emission of AMR into the aquatic envi-ronment.}, subject = {Abwasser}, language = {en} } @article{AlkamLahmer, author = {Alkam, Feras and Lahmer, Tom}, title = {A robust method of the status monitoring of catenary poles installed along high-speed electrified train tracks}, series = {Results in Engineering}, volume = {2021}, journal = {Results in Engineering}, number = {volume 12, article 100289}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.rineng.2021.100289}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211011-45212}, pages = {1 -- 8}, abstract = {Electric trains are considered one of the most eco-friendly and safest means of transportation. Catenary poles are used worldwide to support overhead power lines for electric trains. The performance of the catenary poles has an extensive influence on the integrity of the train systems and, consequently, the connected human services. It became a must nowadays to develop SHM systems that provide the instantaneous status of catenary poles in- service, making the decision-making processes to keep or repair the damaged poles more feasible. This study develops a data-driven, model-free approach for status monitoring of cantilever structures, focusing on pre-stressed, spun-cast ultrahigh-strength concrete catenary poles installed along high-speed train tracks. The pro-posed approach evaluates multiple damage features in an unfied damage index, which leads to straightforward interpretation and comparison of the output. Besides, it distinguishes between multiple damage scenarios of the poles, either the ones caused by material degradation of the concrete or by the cracks that can be propagated during the life span of the given structure. Moreover, using a logistic function to classify the integrity of structure avoids the expensive learning step in the existing damage detection approaches, namely, using the modern machine and deep learning methods. The findings of this study look very promising when applied to other types of cantilever structures, such as the poles that support the power transmission lines, antenna masts, chimneys, and wind turbines.}, subject = {Fahrleitung}, language = {en} } @article{AlsaadVoelker, author = {Alsaad, Hayder and V{\"o}lker, Conrad}, title = {Qualitative evaluation of the flow supplied by personalized ventilation using schlieren imaging and thermography}, series = {Building and Environment}, volume = {2020}, journal = {Building and Environment}, number = {Volume 167, article 106450}, publisher = {Elsevier}, address = {New York}, doi = {10.25643/bauhaus-universitaet.4511}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211008-45117}, pages = {11}, abstract = {Personalized ventilation (PV) is a mean of delivering conditioned outdoor air into the breathing zone of the occupants. This study aims to qualitatively investigate the personalized flows using two methods of visualization: (1) schlieren imaging using a large schlieren mirror and (2) thermography using an infrared camera. While the schlieren imaging was used to render the velocity and mass transport of the supplied flow, thermography was implemented to visualize the air temperature distribution induced by the PV. Both studies were conducted using a thermal manikin to simulate an occupant facing a PV outlet. As a reference, the flow supplied by an axial fan and a cased axial fan was visualized with the schlieren system as well and compared to the flow supplied by PV. Schlieren visualization results indicate that the steady, low-turbulence flow supplied by PV was able to penetrate the thermal convective boundary layer encasing the manikin's body, providing clean air for inhalation. Contrarily, the axial fan diffused the supplied air over a large target area with high turbulence intensity; it only disturbed the convective boundary layer rather than destroying it. The cased fan supplied a flow with a reduced target area which allowed supplying more air into the breathing zone compared to the fan. The results of thermography visualization showed that the supplied cool air from PV penetrated the corona-shaped thermal boundary layer. Furthermore, the supplied air cooled the surface temperature of the face, which indicates the large impact of PV on local thermal sensation and comfort.}, subject = {Bildverarbeitung}, language = {en} } @article{HarirchianKumariJadhavetal., author = {Harirchian, Ehsan and Kumari, Vandana and Jadhav, Kirti and Rasulzade, Shahla and Lahmer, Tom and Raj Das, Rohan}, title = {A Synthesized Study Based on Machine Learning Approaches for Rapid Classifying Earthquake Damage Grades to RC Buildings}, series = {Applied Sciences}, volume = {2021}, journal = {Applied Sciences}, number = {Volume 11, issue 16, article 7540}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/app11167540}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210818-44853}, pages = {1 -- 33}, abstract = {A vast number of existing buildings were constructed before the development and enforcement of seismic design codes, which run into the risk of being severely damaged under the action of seismic excitations. This poses not only a threat to the life of people but also affects the socio-economic stability in the affected area. Therefore, it is necessary to assess such buildings' present vulnerability to make an educated decision regarding risk mitigation by seismic strengthening techniques such as retrofitting. However, it is economically and timely manner not feasible to inspect, repair, and augment every old building on an urban scale. As a result, a reliable rapid screening methods, namely Rapid Visual Screening (RVS), have garnered increasing interest among researchers and decision-makers alike. In this study, the effectiveness of five different Machine Learning (ML) techniques in vulnerability prediction applications have been investigated. The damage data of four different earthquakes from Ecuador, Haiti, Nepal, and South Korea, have been utilized to train and test the developed models. Eight performance modifiers have been implemented as variables with a supervised ML. The investigations on this paper illustrate that the assessed vulnerability classes by ML techniques were very close to the actual damage levels observed in the buildings.}, subject = {Maschinelles Lernen}, language = {en} } @article{Legatiuk, author = {Legatiuk, Dmitrii}, title = {Mathematical Modelling by Help of Category Theory: Models and Relations between Them}, series = {mathematics}, volume = {2021}, journal = {mathematics}, number = {volume 9, issue 16, article 1946}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/math9161946}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210817-44844}, pages = {17}, abstract = {The growing complexity of modern practical problems puts high demand on mathematical modelling. Given that various models can be used for modelling one physical phenomenon, the role of model comparison and model choice is becoming particularly important. Methods for model comparison and model choice typically used in practical applications nowadays are computationbased, and thus time consuming and computationally costly. Therefore, it is necessary to develop other approaches to working abstractly, i.e., without computations, with mathematical models. An abstract description of mathematical models can be achieved by the help of abstract mathematics, implying formalisation of models and relations between them. In this paper, a category theory-based approach to mathematical modelling is proposed. In this way, mathematical models are formalised in the language of categories, relations between the models are formally defined and several practically relevant properties are introduced on the level of categories. Finally, an illustrative example is presented, underlying how the category-theory based approach can be used in practice. Further, all constructions presented in this paper are also discussed from a modelling point of view by making explicit the link to concrete modelling scenarios.}, subject = {Kategorientheorie}, language = {en} } @article{SeichterNesslerKnopf, author = {Seichter, Cosima Zita and Neßler, Miriam and Knopf, Paul}, title = {Mapping In-Betweenness. The Refugee District in Belgrade in the Context of Migration, Urban Development, and Border Regimes}, series = {Movements. Journal for Critical Migration and Border Regime Studies}, volume = {2020}, journal = {Movements. Journal for Critical Migration and Border Regime Studies}, number = {Volume 5, Issue 1}, address = {G{\"o}ttingen}, doi = {10.25643/bauhaus-universitaet.4480}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210806-44807}, pages = {1 -- 9}, abstract = {The contribution explores the migratory situation on the Balkans and more specifically in the so-called Refugee District in Belgrade from a spatial perspective. By visualizing the areas of tensions in the Refugee District, the city of Belgrade, Serbia and Europe it aims to disentangle the political and socio-spatial levels that lead to the stuck situation of in-betweenness at the gates of the European Union.}, subject = {Europ{\"a}ische Union}, language = {en} } @article{SeichterNesslerKnopf, author = {Seichter, Cosima Zita and Neßler, Miriam and Knopf, Paul}, title = {Der Refugee District in Belgrad. Ein Raum der Nicht-Bewegung zwischen neoliberaler Stadtentwicklung, serbischem Migrationsmanagement und EU-Grenzregime}, series = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, volume = {2021}, journal = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, number = {Band 9, Heft 1/2}, publisher = {sub\urban e.V.}, address = {Berlin}, doi = {10.36900/suburban.v9i1/2.622}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210805-44776}, pages = {225 -- 234}, abstract = {Durch internationale Fluchtbewegungen {\"u}ber die sogenannte Balkanroute bildete sich in Serbiens Hauptstadt Belgrad in den letzten Jahren ein sogenannter Refugee District heraus. Im Kontext von Migration und Flucht werden dabei zahlreiche Spannungsfelder auf unterschiedlichen r{\"a}umlichen und politischen Ebenen sichtbar. F{\"u}r Fl{\"u}chtende kreieren diese eine Situation, die von Stillstand, Ausweglosigkeit, Kontrolle, Gefahr und Verdr{\"a}ngung gepr{\"a}gt ist. Allerdings f{\"u}hren die Vielschichtigkeit und die Diversit{\"a}t unterschiedlicher Akteur*innen, die bez{\"u}glich der Situation von Fl{\"u}chtenden auf der Balkanroute wirkm{\"a}chtig sind, auch zu Nischen, Widerst{\"a}ndigkeiten und der M{\"o}glichkeit (neuer) Allianzen. Auf diese Weise entsteht eine kollektive Praktik der Nicht-Bewegung im Widerstand gegen die Unterdr{\"u}ckung und f{\"u}r globale Bewegungsfreiheit.}, subject = {Belgrad}, language = {de} } @article{LegatiukWeiszPatrault, author = {Legatiuk, Dmitrii and Weisz-Patrault, Daniel}, title = {Coupling of Complex Function Theory and Finite Element Method for Crack Propagation Through Energetic Formulation: Conformal Mapping Approach and Reduction to a Riemann-Hilbert Problem}, series = {Computational Methods and Function Theory}, volume = {2021}, journal = {Computational Methods and Function Theory}, publisher = {Springer}, address = {Heidelberg}, doi = {10.1007/s40315-021-00403-7}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210805-44763}, pages = {1 -- 23}, abstract = {In this paper we present a theoretical background for a coupled analytical-numerical approach to model a crack propagation process in two-dimensional bounded domains. The goal of the coupled analytical-numerical approach is to obtain the correct solution behaviour near the crack tip by help of the analytical solution constructed by using tools of complex function theory and couple it continuously with the finite element solution in the region far from the singularity. In this way, crack propagation could be modelled without using remeshing. Possible directions of crack growth can be calculated through the minimization of the total energy composed of the potential energy and the dissipated energy based on the energy release rate. Within this setting, an analytical solution of a mixed boundary value problem based on complex analysis and conformal mapping techniques is presented in a circular region containing an arbitrary crack path. More precisely, the linear elastic problem is transformed into a Riemann-Hilbert problem in the unit disk for holomorphic functions. Utilising advantages of the analytical solution in the region near the crack tip, the total energy could be evaluated within short computation times for various crack kink angles and lengths leading to a potentially efficient way of computing the minimization procedure. To this end, the paper presents a general strategy of the new coupled approach for crack propagation modelling. Additionally, we also discuss obstacles in the way of practical realisation of this strategy.}, subject = {Angewandte Mathematik}, language = {en} } @article{NooriMortazaviKeshtkarietal., author = {Noori, Hamidreza and Mortazavi, Bohayra and Keshtkari, Leila and Zhuang, Xiaoying and Rabczuk, Timon}, title = {Nanopore creation in MoS2 and graphene monolayers by nanoparticles impact: a reactive molecular dynamics study}, series = {Applied Physics A}, volume = {2021}, journal = {Applied Physics A}, number = {volume 127, article 541}, publisher = {Springer}, address = {Heidelberg}, doi = {10.1007/s00339-021-04693-5}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210804-44756}, pages = {1 -- 13}, abstract = {In this work, extensive reactive molecular dynamics simulations are conducted to analyze the nanopore creation by nano-particles impact over single-layer molybdenum disulfide (MoS2) with 1T and 2H phases. We also compare the results with graphene monolayer. In our simulations, nanosheets are exposed to a spherical rigid carbon projectile with high initial velocities ranging from 2 to 23 km/s. Results for three different structures are compared to examine the most critical factors in the perforation and resistance force during the impact. To analyze the perforation and impact resistance, kinetic energy and displacement time history of the projectile as well as perforation resistance force of the projectile are investigated. Interestingly, although the elasticity module and tensile strength of the graphene are by almost five times higher than those of MoS2, the results demonstrate that 1T and 2H-MoS2 phases are more resistive to the impact loading and perforation than graphene. For the MoS2nanosheets, we realize that the 2H phase is more resistant to impact loading than the 1T counterpart. Our reactive molecular dynamics results highlight that in addition to the strength and toughness, atomic structure is another crucial factor that can contribute substantially to impact resistance of 2D materials. The obtained results can be useful to guide the experimental setups for the nanopore creation in MoS2or other 2D lattices.}, subject = {Nanomechanik}, language = {en} } @article{CerejeirasKaehlerLegatiuketal., author = {Cerejeiras, Paula and K{\"a}hler, Uwe and Legatiuk, Anastasiia and Legatiuk, Dmitrii}, title = {Discrete Hardy Spaces for Bounded Domains in Rn}, series = {Complex Analysis and Operator Theory}, volume = {2021}, journal = {Complex Analysis and Operator Theory}, number = {Volume 15, article 4}, publisher = {Springer}, address = {Heidelberg}, doi = {10.1007/s11785-020-01047-6}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210804-44746}, pages = {1 -- 32}, abstract = {Discrete function theory in higher-dimensional setting has been in active development since many years. However, available results focus on studying discrete setting for such canonical domains as half-space, while the case of bounded domains generally remained unconsidered. Therefore, this paper presents the extension of the higher-dimensional function theory to the case of arbitrary bounded domains in Rn. On this way, discrete Stokes' formula, discrete Borel-Pompeiu formula, as well as discrete Hardy spaces for general bounded domains are constructed. Finally, several discrete Hilbert problems are considered.}, subject = {Dirac-Operator}, language = {en} } @article{TutalPartschefeldSchneideretal., author = {Tutal, Adrian and Partschefeld, Stephan and Schneider, Jens and Osburg, Andrea}, title = {Effects of Bio-Based Plasticizers, Made From Starch, on the Properties of Fresh and Hardened Metakaolin-Geopolymer Mortar: Basic Investigations}, series = {Clays and Clay Minerals}, volume = {2020}, journal = {Clays and Clay Minerals}, number = {volume 68, No. 5}, publisher = {Springer}, address = {Heidelberg}, doi = {10.1007/s42860-020-00084-8}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210804-44737}, pages = {413 -- 427}, abstract = {Conventional superplasticizers based on polycarboxylate ether (PCE) show an intolerance to clay minerals due to intercalation of their polyethylene glycol (PEG) side chains into the interlayers of the clay mineral. An intolerance to very basic media is also known. This makes PCE an unsuitable choice as a superplasticizer for geopolymers. Bio-based superplasticizers derived from starch showed comparable effects to PCE in a cementitious system. The aim of the present study was to determine if starch superplasticizers (SSPs) could be a suitable additive for geopolymers by carrying out basic investigations with respect to slump, hardening, compressive and flexural strength, shrinkage, and porosity. Four SSPs were synthesized, differing in charge polarity and specific charge density. Two conventional PCE superplasticizers, differing in terms of molecular structure, were also included in this study. The results revealed that SSPs improved the slump of a metakaolin-based geopolymer (MK-geopolymer) mortar while the PCE investigated showed no improvement. The impact of superplasticizers on early hardening (up to 72 h) was negligible. Less linear shrinkage over the course of 56 days was seen for all samples in comparison with the reference. Compressive strengths of SSP specimens tested after 7 and 28 days of curing were comparable to the reference, while PCE led to a decline. The SSPs had a small impact on porosity with a shift to the formation of more gel pores while PCE caused an increase in porosity. Throughout this research, SSPs were identified as promising superplasticizers for MK-geopolymer mortar and concrete.}, subject = {Geopolymere}, language = {en} } @article{SchirmerOsburg, author = {Schirmer, Ulrike and Osburg, Andrea}, title = {A new method for the quantification of adsorbed styrene acrylate copolymer particles on cementitious surfaces: a critical comparative study}, series = {SN Applied Sciences}, volume = {2020}, journal = {SN Applied Sciences}, number = {Volume 2, article 2061}, publisher = {Springer}, address = {Heidelberg}, doi = {10.1007/s42452-020-03825-5}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210804-44729}, pages = {1 -- 11}, abstract = {The amount of adsorbed styrene acrylate copolymer (SA) particles on cementitious surfaces at the early stage of hydration was quantitatively determined using three different methodological approaches: the depletion method, the visible spectrophotometry (VIS) and the thermo-gravimetry coupled with mass spectrometry (TG-MS). Considering the advantages and disadvantages of each method, including the respectively required sample preparation, the results for four polymer-modified cement pastes, varying in polymer content and cement fineness, were evaluated. To some extent, significant discrepancies in the adsorption degrees were observed. There is a tendency that significantly lower amounts of adsorbed polymers were identified using TG-MS compared to values determined with the depletion method. Spectrophotometrically generated values were ​​lying in between these extremes. This tendency was found for three of the four cement pastes examined and is originated in sample preparation and methodical limitations. The main influencing factor is the falsification of the polymer concentration in the liquid phase during centrifugation. Interactions in the interface between sediment and supernatant are the cause. The newly developed method, using TG-MS for the quantification of SA particles, proved to be suitable for dealing with these revealed issues. Here, instead of the fluid phase, the sediment is examined with regard to the polymer content, on which the influence of centrifugation is considerably lower.}, subject = {Zement}, language = {en} } @article{ReichertOlneyLahmer, author = {Reichert, Ina and Olney, Peter and Lahmer, Tom}, title = {Combined approach for optimal sensor placement and experimental verification in the context of tower-like structures}, series = {Journal of Civil Structural Health Monitoring}, volume = {2021}, journal = {Journal of Civil Structural Health Monitoring}, number = {volume 11}, publisher = {Heidelberg}, address = {Springer}, doi = {10.1007/s13349-020-00448-7}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210804-44701}, pages = {223 -- 234}, abstract = {When it comes to monitoring of huge structures, main issues are limited time, high costs and how to deal with the big amount of data. In order to reduce and manage them, respectively, methods from the field of optimal design of experiments are useful and supportive. Having optimal experimental designs at hand before conducting any measurements is leading to a highly informative measurement concept, where the sensor positions are optimized according to minimal errors in the structures' models. For the reduction of computational time a combined approach using Fisher Information Matrix and mean-squared error in a two-step procedure is proposed under the consideration of different error types. The error descriptions contain random/aleatoric and systematic/epistemic portions. Applying this combined approach on a finite element model using artificial acceleration time measurement data with artificially added errors leads to the optimized sensor positions. These findings are compared to results from laboratory experiments on the modeled structure, which is a tower-like structure represented by a hollow pipe as the cantilever beam. Conclusively, the combined approach is leading to a sound experimental design that leads to a good estimate of the structure's behavior and model parameters without the need of preliminary measurements for model updating.}, subject = {Strukturmechanik}, language = {en} }