@article{SchneidereitBreuss2023, author = {Schneidereit, Toni and Breuß, Michael}, title = {Adaptive neural-domain refinement for solving time-dependent differential equations}, doi = {10.1186/s13662-023-03789-x}, year = {2023}, abstract = {A classic approach for solving differential equations with neural networks builds upon neural forms, which employ the differential equation with a discretisation of the solution domain. Making use of neural forms for time-dependent differential equations, one can apply the recently developed method of domain segmentation. That is, the domain may be split into several subdomains, on which the optimisation problem is solved. In classic adaptive numerical methods, the mesh as well as the domain may be refined or decomposed, in order to improve the accuracy. Also, the degree of approximation accuracy may be adapted. Therefore, it is desirable to transfer such important and successful strategies to the field of neural-network-based solutions. In the presented work, we propose a novel adaptive neural approach to meet this aim for solving time-dependent problems. To this end, each subdomain is reduced in size until the optimisation is resolved up to a predefined training accuracy. In addition, while the neural networks employed are by default small, we propose a means to adjust also the number of neurons in an adaptive way. We introduce conditions to automatically confirm the solution reliability and optimise computational parameters whenever it is necessary. Results are provided for several initial-value problems that illustrate important computational properties of the method.}, subject = {Neural forms; Differential equations; Physics-informed neural networks; Adaptive neural refinement; Domain decomposition; Neuronale Formen; Differentialgleichungen; Physikalisch informierte neuronale Netze; Adaptive neuronale Verfeinerung; Gebietszerlegung; Differentialgleichung; Neuronales Netz}, language = {en} } @article{GeyerWindischFritscheetal.2023, author = {Geyer, Thomas and Windisch, Thomas and Fritsche, Christoph and Sarradj, Ennes}, title = {Dataset on permeability of wings from owls and non-silently flying birds}, doi = {10.1016/j.dib.2023.109825}, year = {2023}, abstract = {The very soft and flow-permeable plumage is among the special adaptations of the owl that the silent flight is attributed to. Using a specially designed apparatus that provides a low-speed volume flow of air through a small sample of porous materials, measurements of the air flow permeability were performed in accordance to ISO 9053 on a total of 39 prepared wing specimen from six different bird species, including three species of silently flying owls and three non-silently flying bird species. The resulting data set described in the present paper contains the static airflow resistance measured at different positions on the wing.}, subject = {Owl wing; Air flow resistivity; Permeability; Silent flight; Acoustics; leiser Eulenflug; Str{\"o}mungswiderstand; Permeabilit{\"a}t; Eulenflug; Akustik; Eulen; Vogelflug; Str{\"o}mungswiderstand; Akustik; Permeabilit{\"a}t}, language = {en} } @inproceedings{RuedaEscobedoMorenoSchiffer, author = {Rueda-Escobedo, Juan G. and Moreno, Jaime A. and Schiffer, Johannes}, title = {Finite-time estimation of time-varying frequency signals in low-inertia power systems}, doi = {10.26127/BTUOpen-5988}, pages = {2108 -- 2114}, abstract = {The ongoing and unprecedented transformation of power systems leads to a reduction in the number of conventional power plants, which are the classical actuators of the grid. In addition, this development results in a decreasing system inertia, which is expected to yield faster frequency dynamics. Therefore power-electronics-interfaced units have to take over system control tasks and, in particular, frequency control. For this purpose, accurate and fast estimation algorithms for time-varying frequency signals are needed. Motivated by this fact, we propose a time-varying parameter estimator and a tuning criterion, which for sufficiently small initial estimation errors allows to reconstruct the time-varying frequency signal of a symmetric three-phase waveform in finite time. The proposed estimator is derived by using a time-varying version of the super twisting algorithm and its performance is illustrated via numerical examples.}, subject = {Distributed power generation; Frequency control; Parameter estimation; Power plants; Power system control; Frequenzsignale; Massentr{\"a}gheit; Systemsteuerung; Transformation; Frequenzdynamik; Energieversorgung; Frequenzstabilit{\"a}t}, language = {en} } @inproceedings{SegabinazziFerreiraNolte2019, author = {Segabinazzi Ferreira, Raphael and Nolte, J{\"o}rg}, title = {Low latency reconfiguration mechanism for fine-grained processor internal functional units}, doi = {10.1109/LATW.2019.8704560}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-50497}, year = {2019}, abstract = {The strive for performance, low power consumption, and less chip area have been diminishing the reliability and the time to fault occurrences due to wear out of electronic devices. Recent research has shown that functional units within processors usually execute a different amount of operations when running programs. Therefore, these units present different individual wear out during their lifetime. Most existent schemes for re-configuration of processors due to fault detection and other processor parameters are done at the level of cores which is a costly way to achieve redundancy. This paper presents a low latency (approximately 1 clock cycle) software controlled mechanism to reconfigure units within processor cores according to predefined parameters. Such reconfiguration capability delivers features like wear out balance of processor functional units, configuration of units according to the criticality of tasks running on an operating system and configurations to gain in performance (e.g. parallel execution) when possible. The focus of this paper is to show the implemented low latency reconfiguration mechanism and highlight its possible main features.}, subject = {Functional units low latency; Fine-grained; Reconfiguration; Software; Rekonfiguration; Mikroprozessor; Latenzzeit }, language = {en} } @inproceedings{RottaSegabinazziFerreiraNolte2020, author = {Rotta, Randolf and Segabinazzi Ferreira, Raphael and Nolte, J{\"o}rg}, title = {Real-time dynamic hardware reconfiguration for processors with redundant functional units}, series = {Proceedings of the 2020 IEEE 23rd International Symposium on Real-Time Distributed Computing (ISORC)}, booktitle = {Proceedings of the 2020 IEEE 23rd International Symposium on Real-Time Distributed Computing (ISORC)}, publisher = {Institute of Electrical and Electronics Engineers Inc. (IEEE)}, address = {Nashville, TN, USA}, isbn = {978-1-7281-6958-3}, issn = {2375-5261}, doi = {10.1109/ISORC49007.2020.00035}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-52031}, year = {2020}, abstract = {The tiny logic elements in modern integrated circuits increase the rate of transient failures significantly. Therefore, redundancy on various levels is necessary to retain reliability. However, for mixed-criticality scenarios, the typical processor designs offer either too little fault-tolerance or too much redundancy for one part of the applications. Amongst others, we specifically address redundant processor internal functional units (FU) to cope with transient errors and support wear leveling. A real-time operating system (RTOS) was extended to control our prototypical hardware platform and, since it can be configured deterministically within few clock cycles, we are able to reconfigure the FUs dynamically, at process switching time, according to the specified critically of the running processes. Our mechanisms were integrated into the Plasma processor and the Plasma-RTOS. With few changes to the original software code, it was, for example, possible to quickly change from fault-detecting to fault-correcting modes of the processor on demand.}, subject = {Reconfiguration; Run-Time; Modular redundancy; Mixed-criticality; Rekonfiguration; Laufzeit; Funktionseinheit; Redundanz }, language = {en} } @article{RichterRachowIsraeletal.2023, author = {Richter, Jana and Rachow, Fabian and Israel, Johannes and Roth, Norbert and Charlafti, Evgenia and G{\"u}nther, Vivien and Flege, Jan Ingo and Mauss, Fabian}, title = {Reaction mechanism development for methane steam reforming on a Ni/Al2O3 catalyst}, doi = {10.3390/catal13050884}, year = {2023}, abstract = {In this work, a reliable kinetic reaction mechanism was revised to accurately reproduce the detailed reaction paths of steam reforming of methane over a Ni/Al2O3 catalyst. A steadystate fixed-bed reactor experiment and a 1D reactor catalyst model were utilized for this task. The distinctive feature of this experiment is the possibility to measure the axially resolved temperature profile of the catalyst bed, which makes the reaction kinetics inside the reactor visible. This allows for understanding the actual influence of the reaction kinetics on the system; while pure gas concentration measurements at the catalytic reactor outlet show near-equilibrium conditions, the inhere presented temperature profile shows that it is insufficient to base a reaction mechanism development on close equilibrium data. The new experimental data allow for achieving much higher quality in the modeling efforts. Additionally, by carefully controlling the available active surface via dilution in the experiment, it was possible to slow down the catalyst conversion rate, which helped during the adjustment of the reaction kinetics. To assess the accuracy of the revised mechanism, a monolith experiment from the literature was simulated. The results show that the fitted reaction mechanism was able to accurately predict the experimental outcomes for various inlet mass flows, temperatures, and steam-to-carbon ratios.}, subject = {1D modeling; Reaction rates; Methane steam reforming; Fixed-bed reactor experiments; Nickel catalyst; 1D-Modellierung; Reaktionsgeschwindigkeiten; Methan-Dampfreformierung; Festbettreaktor-Experimente; Nickel-Katalysator; Katalysator; Reaktionsmechanismus; Festbettreaktor; Steamreforming; Reaktionsgeschwindigkeit}, language = {en} } @article{Zeissig2023, author = {Zeißig, Anke}, title = {Boredom as the originator of a desideratum : reflections on the creative and suppressive consequences of boredom in the school context}, doi = {10.3389/fsoc.2023.1214069}, year = {2023}, abstract = {Bored children begin to draw, do crafts, to fidget - or they do something bad. Others fall silent, withdraw, or become lethargic. Research on school-related boredom has focused primarily on the negative consequences of boredom, such as decreased cognitive performance, motivation or attentativeness, or disruptiveness. These negative aspects of boredom can be contrasted by the notion that boredom can promote creative performance. This paper reflects on boredom's creative and suppressive consequences as an interplay of personality traits and behavioral possibilities in school situations, on the one hand, and as an interplay of situational experiences with constituent developmental processes on the other. It is proposed that boredom is a gauge of the learner's resonance with school content, learning and/or developmental relationships. Boredom indicates a psychological need and its desideratum. Thus, both creative and suppressive potentials are inherent in boredom.}, subject = {Boredom; Creativity; Education; School; Langeweile; Kreativit{\"a}t; Bildung; Schule; Spiritualit{\"a}t; Bildung; Kind; Kognitive Entwicklung; Langeweile; Sozialp{\"a}dagogik; Boredom; Education}, language = {en} } @article{AliKhanKolendaetal.2023, author = {Ali, Aamir and Khan, Muhammad Moman and Kolenda, Rafal and Olowe, Olugbenga Adekunie and Weinreich, J{\"o}rg and Li, Ganwu and Schierack, Peter}, title = {The role of AJB35136 and fdtA genes in biofilm formation by avian pathogenic Escherichia coli}, doi = {10.1186/s12917-023-03672-7}, year = {2023}, abstract = {Background Infections caused by avian pathogenic Escherichia coli (APEC) result in significant economic losses in poultry industry. APEC strains are known to form biofilms in various conditions allowing them to thrive even under harsh and nutrient-deficient conditions on different surfaces, and this ability enables them to evade chemical and biological eradication methods. Despite knowing the whole genome sequences of various APEC isolates, little has been reported regarding their biofilm-associated genes. A random transposon mutant library of the wild-type APEC IMT 5155 comprising 1,300 mutants was analyzed for biofilm formation under nutrient deprived conditions using Videoscan technology coupled with fluorescence microscopy. Seven transposon mutants were found to have reproducibly and significantly altered biofilm formation and their mutated genes were identified by arbitrary PCR and DNA sequencing. The intact genes were acquired from the wild-type strain, cloned in pACYC177 plasmid and transformed into the respective altered biofilm forming transposon mutants, and the biofilm formation was checked in comparison to the wild type and mutant strains under the same conditions. Results In this study, we report seven genes i.e., nhaA, fdeC, yjhB, lysU, ecpR, AJB35136 and fdtA of APEC with significant contribution to biofilm formation. Reintroduction of AJB35136 and fdtA, reversed the altered phenotype proving that a significant role being played by these two O-antigen related genes in APEC biofilm formation. Presence of these seven genes across nonpathogenic E. coli and APEC genomes was also analyzed showing that they are more prevalent in the latter.}, subject = {APEC; Biofilm; Gene; Complementation; Transposon mutant; VideoScan; Genkomplementierung; Transposon-Mutanten; Gefl{\"u}gelkrankheit; Escherichia coli; Biofilm; Komplementation; Transponson; Mutant}, language = {en} } @inproceedings{Schmitt2023, author = {Schmitt, Rebecca Erika}, title = {The geometric design of Christoph Dientzenhofer's 'radical' vaults}, doi = {10.26127/BTUOpen-6408}, year = {2023}, abstract = {Christoph Dientzenhofer (1655-1722) is considered one of the most important Baroque master builders of Central Europe. From his extensive architectural oeuvre, a group of six church buildings with geometrically complex forms stands out, recognised by architectural historians as particularly innovative and influential. These churches, located in Bohemia (Czech Republic), and often collectively referred to as the 'radical', 'dynamic', 'Guarinesque', or simply 'Bohemian' group, are: St. Joseph in Obořiště (1702-11), the Castle Church in Smiřice (1702-11), St. Nicholas in the Lesser Town of Prague (1703-11), St. Clare in Cheb (1707-11), St. Margaret in Břevnov (1708-16), and the Church of the Holy Assumption in Nov{\´a} Paka (1709-24). The brick vaults of these six buildings, sequences of oval domes and double-curved vault areas, are of particular interest for building research. In this study, the geometric design of the vaults of Dientzenhofer's 'radical' churches is documented, analysed, and compared using 3D laser scans of the buildings as primary source. The 3D models generated from the scans enable a geometric analysis through the method of reverse geometric engineering, breaking down the vaults' complex three-dimensional forms into their basic two-dimensional components: segments of circles with different radii and orientations, curved in one or two directions. These forms can be found in the architectural and stereotomic treatises that were widespread at the time. By comparing the vault geometry of the six churches with each other and with the geometric concepts discussed in the treatises, general statements can be made about the architect's design choices. On the basis of this investigation, hypotheses are made about the design and underlying geometric ideas of the vaults of Dientzenhofer's 'radical group', and the results are placed in context.}, subject = {Geometric Design; Brick Vault; Christoph Dientzenhofer; Reverse Engineering; Stereotomy; Geometrischer Entwurf; Backsteingew{\"o}lbe; Reverse Engineering; Stereotomie; Dietzenhofer, Christoph; Kirchenbau; Baugestaltung; Gew{\"o}lbe; Ziegel; Geometrie; Dreidimensionales Modell}, language = {en} } @article{CelikAtapekPolatetal.2023, author = {{\c{C}}elik, G{\"u}l{\c{s}}ah Akta{\c{s}} and Atapek, Şaban Hakan and Polat, Şeyda and Obrosov, Aleksei and Weiß, Sabine}, title = {Nitriding effect on the tribological performance of CrN-, AlTiN-, and CrN/AlTiN-Coated DIN 1.2367 hot work tool steel}, doi = {10.3390/ma16072804}, year = {2023}, abstract = {In this study, heat-treated and multisurface engineered DIN 1.2367 tool steel was subjected to room and elevated temperature wear tests, and the effect of nitriding on its tribological behavior was investigated. CrN, AlTiN, and CrN/AlTiN coatings with a total thickness of 2 µm were obtained by arc cathodic physical vapor deposition on conventional heat-treated and gas-nitrided steels. The white layer formed during nitriding was removed, and a diffusion layer (100 µm) was achieved in the cross section of the steel having a tempered martensitic matrix. The highest surface hardness was attained with an integral coating (CrN/AlTiN), and surface hardness increased even more after nitriding due to the formation of a multicomponent ceramic layer on top of the diffusion layer. The room temperature wear tests performed against an alumina counterpart revealed that (i) CrN/AlTiN-coated steel had the highest friction coefficient of 0.26, which further increased to 0.33 by nitriding due to the increase in shear strength, and that (ii) with increasing surface hardness, the specific wear rates (W) of the heat-treated and coated steels could be ranked as follows: WCrN/AlTiN < WAlTiN < WCrN. The wear rates decreased when nitriding was carried out prior to coating. In order to simulate the aluminum extrusion conditions, hot wear behavior of the surfaces against AA6080 alloy at 450 °C was investigated. The hot wear tests revealed that (i) high friction coefficients were reached due to the adhesive characteristic of aluminum to the surfaces, (ii) the nitrided and CrN/AlTiN-coated sample exhibited the lowest wear rate among all studied surfaces, and (iii) the film damage on the worn surfaces mostly occurred in the form of droplet delamination.}, subject = {DIN 1.2367; PVD coating; Wear; Characterization; PVD-Beschichtung; Verschleiß; Charakterisierung; Werkzeugstahl; Warmarbeitsstahl; Nitrierh{\"a}rten; Tribologie; Werkzeugpr{\"u}fung; Verschleiß}, language = {en} } @article{BoltonLaaser2017, author = {Bolton, Sharon C. and Laaser, Knut}, title = {The moral economy of solidarity: A longitudinal study of special needs teachers}, publisher = {SAGE Publications}, address = {London, England}, issn = {0950-0170}, doi = {10.1177/0950017019871237}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-52124}, year = {2017}, abstract = {Based on a longitudinal study of a Pupil Referral Unit (PRU) in England for children excluded from mainstream schools and utilising a moral economy lens, this article explores how solidarity is created and maintained in a very particular community of teachers and learning support assistants (LSAs). A moral economy approach highlights the centrality of people's moral norms and values for understanding the multi-layered dimensions of solidarity in organisations and how it changes in the context of transformations in the labour process. The article illustrates how teachers and LSAs rely on mutuality, underpinned by moral norms of justice, and values of care, dignity and recognition, to cope with physically and emotionally demanding work that is under-resourced and undervalued. The analysis reveals that solidarity is not only against unjust workplace regimes, but also for connectivity and a humanised labour process.}, subject = {England; Moral economy; Inequality; Pupil Referral Unit; Schools; Solidarity; Sonderschule; Lehrerkollegium; Solidarit{\"a}t; Moral; Norm }, language = {en} } @incollection{BhutaniBoesGoetteletal., author = {Bhutani, A. and Boes, F. and Goettel, B. and Schaefer, J. and Eisenbeis, J. and Zwick, T. and Malz, Stefan and Rodriguez Vazquez, Pedro and Grzyb, Janusz and Pfeiffer, Ulrich}, title = {Real100G.RF : a fully integrated, multi-purpose radio front-end for wireless 100 Gbps}, series = {Wireless 100 Gbps and beyond : architectures, approaches and findings of German Research Foundation (DFG) Priority Programme SPP1655}, booktitle = {Wireless 100 Gbps and beyond : architectures, approaches and findings of German Research Foundation (DFG) Priority Programme SPP1655}, doi = {10.26127/BTUOpen-5915}, publisher = {BTU Cottbus - Senftenberg}, pages = {295 -- 354}, abstract = {In 2012 a group of researchers proposed a basic research initiative to the German Research Foundation (DFG) as a special priority project (SPP) with the name: Wireless 100 Gbps and beyond. The main goal of this initiative was the investigation of architectures, technologies and methods to go well beyond the state of the art. The target of 100 Gbps was set far away from the (at that time) achievable 1 Gbps such that it was not possible to achieve promising results just by tuning some parameters. We wanted to find breakthrough solutions. When we started the work on the proposal we discussed the challenges to be addressed in order to advancing the wireless communication speed significantly. Having the fundamental Shannon boundary in mind we discussed how to achieve the 100 Gbps speed.}, subject = {100 Gbps; Wireless; Drahtlos; Real100G.RF; Fully integrated; Multi-purpose radio front-end; Vollst{\"a}ndig integriert; Vielseitig anwendbare Funkeingangsstufe; Drahtloses Sensorsystem; Hochfrequenztechnik; Antenne; Terahertzbereich; Energieffizienz}, language = {en} } @article{HanReiterSchlipfetal.2023, author = {Han, Weijia and Reiter, Sebastian and Schlipf, Jon and Mai, Christian and Spirito, Davide and Jose, Josmy and Wenger, Christian and Fischer, Inga A.}, title = {Strongly enhanced sensitivities of CMOS compatible plasmonic titanium nitride nanohole arrays for refractive index sensing under oblique incidence}, doi = {10.1364/OE.481993}, year = {2023}, abstract = {Titanium nitride (TiN) is a complementary metal-oxide-semiconductor (CMOS) compatible material with large potential for the fabrication of plasmonic structures suited for device integration. However, the comparatively large optical losses can be detrimental for application. This work reports a CMOS compatible TiN nanohole array (NHA) on top of a multilayer stack for potential use in integrated refractive index sensing with high sensitivities at wavelengths between 800 and 1500 nm. The stack, consisting of the TiN NHA on a silicon dioxide (SiO2) layer with Si as substrate (TiN NHA/SiO2/Si), is prepared using an industrial CMOS compatible process. The TiN NHA/SiO2/Si shows Fano resonances in reflectance spectra under oblique excitation, which are well reproduced by simulation using both finite difference time domain (FDTD) and rigorous coupled-wave analysis (RCWA) methods. The sensitivities derived from spectroscopic characterizations increase with the increasing incident angle and match well with the simulated sensitivities. Our systematic simulation-based investigation of the sensitivity of the TiN NHA/SiO2/Si stack under varied conditions reveals that very large sensitivities up to 2305 nm per refractive index unit (nm RIU-1) are predicted when the refractive index of superstrate is similar to that of the SiO2 layer. We analyze in detail how the interplay between plasmonic and photonic resonances such as surface plasmon polaritons (SPPs), localized surface plasmon resonances (LSPRs), Rayleigh Anomalies (RAs), and photonic microcavity modes (Fabry-P{\´e}rot resonances) contributes to this result. This work not only reveals the tunability of TiN nanostructures for plasmonic applications but also paves the way to explore efficient devices for sensing in broad conditions.}, subject = {TiN; Plasmonics; Plasmonik; Plasmonik; Photonik; Titannitrid; Plasmonics; Photonics}, language = {en} } @article{AsliKimHoeschler2023, author = {Asli, Majid and Kim, Dongsuk and H{\"o}schler, Klaus}, title = {On the potentials of the integration of pressure gain combustion with a hybrid electric propulsion system}, doi = {10.3390/aerospace10080710}, year = {2023}, abstract = {As the issue of pollutant emissions from aviation propulsion escalates, research into alternative powertrains is gaining momentum. Two promising technologies are the Hybrid Electric Propulsion System (HEPS) and Pressure Gain Combustion (PGC). HEPS is expected to reduce pollutant emissions by decreasing fuel consumption, whereas PGC uses detonation in the combustor to increase the thermal efficiency of engines by elevating the total pressure during combustion. This study extensively explores the integration of these two emerging technologies, thoroughly assessing the advantages that arise from their combination. First, the renowned turboprop engine PW127 is benchmarked and modeled using Gasturb software. The model is integrated into Simulink using the T-MATS tool, with HEPS and pressure gain components added to analyze the thermodynamics of various configurations under different pressure gain values and HEPS parameters. The analysis, conducted up to the cruise phase of the baseline aircraft, reveals that applying pressure gain combustion through Rotating Detonation Combustion (RDC) results in a more significant increase in efficiency and decrease in fuel consumption compared to HEPS with conventional gas turbines. However, HEPS helps maintain a more uniform combustor inlet condition and reduces the Turbine Inlet Temperature (TIT) at the takeoff phase, where the highest TIT otherwise occurs. The results suggest that integrating HEPS with PGC can be beneficial in maintaining optimal combustor conditions and mitigating turbine efficiency degradation.}, subject = {Pressure gain combustion; Hybrid electric propulsion; Rotating detonation combustion; Druckverst{\"a}rkungsverbrennung; Rotierende Detonationsverbrennung; Hybrid-Elektroantrieb; Propeller-Turbinen-Luftstrahltriebwerk; Hybridantrieb; Verbrennung; Schadstoffemission; Emissionsverringerung}, language = {en} } @incollection{WendlandGielen, author = {Wendland, David and Gielen, Mark}, title = {The design and construction of the vaults in Notre-Dame in Paris and the development of medieval vaulting and stereotomy : surveys, analyses and experiments}, doi = {10.26127/BTUOpen-6060}, publisher = {BTU Cottbus - Senftenberg}, abstract = {Among the many innovative church constructions in the {\^I}le-de-France during the twelfth century that immediately followed the ground-breaking new building of the abbey church of Saint-Denis, the high vaults in the cathedral of Notre-Dame in Paris mark a turning point - both in sheer dimensions and in their quality of execution as stone constructions. On the other hand, some solutions in design and construction that can be observed in these vaults remain unique within the dynamic development of Gothic vaulting in the great cathedrals built in the following years. On closer view it turns out that the general design of the vault as well as its construction details are hardly understood until now, mainly because they have been overlooked in a unifying perspective on Gothic architecture coined by the idealistic view of the Gothic Revival in the nineteenth century. Further, the particular relation between vault design and stereotomy needs to be clarified, and its significance needs to be understood.}, subject = {Vault; Medieval architecture; Gothic; Notre-Dame de Paris; Speyer Cathedral; Gew{\"o}lbe; Mittelalterliche Architektur; Gotik; Dom zu Speyer; Notre-Dame (Paris); Kirchenbau; Gew{\"o}lbe; Gotik}, language = {en} } @article{FrankenNetzerMaussetal., author = {Franken, Tim and Netzer, Corinna and Mauss, Fabian and Pasternak, Michal and Seidel, Lars and Borg, Anders and Lehtiniemi, Harry and Matrisciano, Andrea and Kulzer, Andre Casal}, title = {Multi-objective optimization of water injection in spark-ignition engines using the stochastic reactor model with tabulated chemistry}, publisher = {SAGE Publications}, address = {London, England}, issn = {1468-0874}, doi = {10.1177/1468087419857602}, abstract = {Water injection is investigated for turbocharged spark-ignition engines to reduce knock probability and enable higher engine efficiency. The novel approach of this work is the development of a simulation-based optimization process combining the advantages of detailed chemistry, the stochastic reactor model and genetic optimization to assess water injection. The fast running quasi-dimensional stochastic reactor model with tabulated chemistry accounts for water effects on laminar flame speed and combustion chemistry. The stochastic reactor model is coupled with the Non-dominated Sorting Genetic Algorithm to find an optimum set of operating conditions for high engine efficiency. Subsequently, the feasibility of the simulation-based optimization process is tested for a three-dimensional computational fluid dynamic numerical test case. The newly proposed optimization method predicts a trade-off between fuel efficiency and low knock probability, which highlights the present target conflict for spark-ignition engine development. Overall, the optimization shows that water injection is beneficial to decrease fuel consumption and knock probability at the same time. The application of the fast running quasi-dimensional stochastic reactor model allows to run large optimization problems with low computational costs. The incorporation with the Non-dominated Sorting Genetic Algorithm shows a well-performing multi-objective optimization and an optimized set of engine operating parameters with water injection and high compression ratio is found.}, subject = {Ottomotor; Water injection; Genetic optimization; Spark-ignition engine; Stochastic reactor model; Detailed chemistry; Wassereinspritzung; Prozessoptimierung; Stochastisches Modell}, language = {en} } @inproceedings{Schmitt, author = {Schmitt, Rebecca Erika}, title = {Geometric design and construction of a Late Baroque brick vault : Kilian Ignaz Dientzenhofer's Benedictine Church of the Holy Cross and St. Hedwig at Legnickie Pole}, doi = {10.26127/BTUOpen-5905}, abstract = {This paper investigates the case study of Kilian Ignaz Dientzenhofer's church of St. Hedwig in the Polish region of Silesia. The building, a popular pilgrimage church, is known in the history of art and architecture as a Late Baroque jewel with a curious design and famous frescoes. While the shape of the building and its vault has led to different interpretations in the past, its geometry has not yet been analysed on a reliable basis. Moreover, the construction of the brick vault has not yet been subject to scientific research. In order to investigate these aspects, a 3D laser scan of the vault's extrados and intrados was utilised as the primary source. The 3D model generated from the scan not only enabled the detailed description of structural ribs, brick patterns and construction details on the extrados, but also made a geometrical analysis using reverse geometric engineering possible. The results show a geometric design of the vault surfaces as well as double-curved arches based on simple plane circle segments. This clear geometric definition of the vault is associated with a remarkable simplicity of construction method and centering. In the context of other vault designs by members of the Dientzenhofer professional circle of master builders and architects, the vault of St. Hedwig can be seen as both a continuation and an improvement in terms of geometric design and construction details.}, subject = {Kilian Ignaz Dientzenhofer; Legnickie Pole; Geometric design; Construction; Vault; Geometrischer Entwurf; Konstruktion; Gew{\"o}lbe; Dientzenhofer; Kilian Ignaz; Wahlstatt (Liegnitz); Kirchenbau; Gew{\"o}lbe; Dreidimensionale Rekonstruktion; Geometrie}, language = {en} } @article{FrimpongMolkenthinKoranteng2022, author = {Frimpong, Bernard Fosu and Molkenthin, Frank and Koranteng, Addo}, title = {Analysis of temperature variability utilising Mann-Kendall and Sen's slope estimator tests in the Accra and Kumasi metropolises in Ghana}, doi = {10.1186/s40068-022-00269-1}, year = {2022}, abstract = {Temperature variability may have direct and indirect impacts on the environments of the Accra and Kumasi Metropolises in Ghana. This study analysed temperature and trends in temperature in both cities using in-situ measurements from one meteorological station in both cities from 1986 to 2015. The temperature indices were computed using the RClimdex package from the Expert Team on Climate Change Detection Monitoring Indices (ETCCDMI). The temperature time series was pre-whitened before the Mann-Kendall trend and Sen's slope estimator analysis were applied. Initial analysis revealed minimal variation in temperature in both cities. The results from the analysed temperature indices revealed an increase in warm days and a general rise in the minimum temperature compared to maximum temperatures. Mann Kendall and Sen's slope revealed significant trends in the annual and seasonal (dry and wet seasons) in minimum temperature in both cities. These might lead to an increased rate of heat-stressed diseases and an overall rise in urban warming in both cities. The analysis of temperature, indices and trends provided comprehensive insights into the temperature of Accra and Kumasi. The results highlight the essence of evaluating temperature indices and trends in light of Climate Change concerns. It is recommended that urban green and blue spaces should be incorporated into land use plans as these policy directions can aid regulate the temperature in both cities.}, subject = {Temperature variability; Mann-Kendall test; Sen's slope estimator; Accra; Kumasi; Temperaturvarabilit{\"a}t; Sen-Slope Sch{\"a}tzer; Accra; Kumasi; Temperatur; Schwankung}, language = {en} } @inproceedings{SegabinazziFerreiraGeorgeChenetal.2019, author = {Segabinazzi Ferreira, Raphael and George, Nevin and Chen, Junchao and H{\"u}bner, Michael and Krstic, Milos and Nolte, J{\"o}rg and Vierhaus, Heinrich Theodor}, title = {Configurable Fault Tolerant Circuits and System Level Integration for Self-Awareness}, isbn = {978-3-902457-54-7}, doi = {10.26127/BTUOpen-5050}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-50503}, year = {2019}, abstract = {Scaling minimum features of ICs down to the 10nm- area and below has allowed high integration rates in electronics. Scaling at supply voltages of 1V and below also implies a rising level of stress which drives aging effects that reduce switching speed and the expected life time. Additionally, vulnerability from particle radiation is increased. Hence, fault detection and on-line correction become a must for many applications. However, not only fault tolerance but self-awareness becomes also an advantage. Provided that by being aware of its own healthy state allow optimized configurations regarding system operation modes and configurable hardware mechanism. This paper shows a preliminary work in a configurable circuit and explores its configuration possibilities when integrated into a complete system.}, subject = {Self-awareness; Configurable circuits; Fault tolerant; Operation modes; Integrierte Schaltung; Konfiguration ; Fehlertoleranz}, language = {en} } @incollection{SchmittWendland, author = {Schmitt, Rebecca Erika and Wendland, David}, title = {The geometric design of the "Guarinesque" vaults in Banz and Vierzehnheiligen in relation to the treatises of stereotomy}, doi = {10.26127/BTUOpen-5904}, publisher = {BTU Cottbus - Senftenberg}, abstract = {Johann Dientzenhofer's Banz Abbey Church (1710-1718) and Balthasar Neumann's church of Vierzehnheiligen (1743-1772), both located in Upper Franconia (Germany), are characterised by their masonry vaults, sequences of oval domes separated by double-curved arches. This Late Baroque architecture has been called "Guarinesque"; however, the conceptual connection between the vaults and Guarino Guarini's architecture remains to be thoroughly investigated. This paper resumes the discussion about the geometric definitions of these vaults using the modern methods of geometric analysis and reverse geometrical engineering, based on 3D laser scanning. The analysis of these scans reveals a design process based on plane circle segments and ovals, while more complex geometric procedures are not necessary to describe the vaults. Further, the relationship between these designs and the procedures of geometric design described in the treatises of stereotomy since the 16th century can be shown. On this background, the relation to Guarini's Architettura Civile (1737) is discussed.}, subject = {Balthasar Neumann; Johann Dientzenhofer; Vierzehnheiligen; Banz; Vault; Gew{\"o}lbe; Klosterkirche Banz (Bad Staffelstein); Wallfahrtskirche Vierzehnheiligen (Staffelstein); Kirchenbau; Gew{\"o}lbe; Dreidimensionale Rekonstruktion; Geometrie}, language = {en} }