@article{ChromikKirstenHerdicketal.2022, author = {Chromik, Jonas and Kirsten, Kristina and Herdick, Arne and Kappattanavar, Arpita Mallikarjuna and Arnrich, Bert}, title = {SensorHub}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s22010408}, pages = {18}, year = {2022}, abstract = {Observational studies are an important tool for determining whether the findings from controlled experiments can be transferred into scenarios that are closer to subjects' real-life circumstances. A rigorous approach to observational studies involves collecting data from different sensors to comprehensively capture the situation of the subject. However, this leads to technical difficulties especially if the sensors are from different manufacturers, as multiple data collection tools have to run simultaneously. We present SensorHub, a system that can collect data from various wearable devices from different manufacturers, such as inertial measurement units, portable electrocardiographs, portable electroencephalographs, portable photoplethysmographs, and sensors for electrodermal activity. Additionally, our tool offers the possibility to include ecological momentary assessments (EMAs) in studies. Hence, SensorHub enables multimodal sensor data collection under real-world conditions and allows direct user feedback to be collected through questionnaires, enabling studies at home. In a first study with 11 participants, we successfully used SensorHub to record multiple signals with different devices and collected additional information with the help of EMAs. In addition, we evaluated SensorHub's technical capabilities in several trials with up to 21 participants recording simultaneously using multiple sensors with sampling frequencies as high as 1000 Hz. We could show that although there is a theoretical limitation to the transmissible data rate, in practice this limitation is not an issue and data loss is rare. We conclude that with modern communication protocols and with the increasingly powerful smartphones and wearables, a system like our SensorHub establishes an interoperability framework to adequately combine consumer-grade sensing hardware which enables observational studies in real life.}, language = {en} } @article{ArboledaZapataGuillemoteauTronicke2022, author = {Arboleda-Zapata, Mauricio and Guillemoteau, Julien and Tronicke, Jens}, title = {A comprehensive workflow to analyze ensembles of globally inverted 2D electrical resistivity models}, series = {Journal of applied geophysics}, volume = {196}, journal = {Journal of applied geophysics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0926-9851}, doi = {10.1016/j.jappgeo.2021.104512}, pages = {12}, year = {2022}, abstract = {Electrical resistivity tomography (ERT) aims at imaging the subsurface resistivity distribution and provides valuable information for different geological, engineering, and hydrological applications. To obtain a subsurface resistivity model from measured apparent resistivities, stochastic or deterministic inversion procedures may be employed. Typically, the inversion of ERT data results in non-unique solutions; i.e., an ensemble of different models explains the measured data equally well. In this study, we perform inference analysis of model ensembles generated using a well-established global inversion approach to assess uncertainties related to the nonuniqueness of the inverse problem. Our interpretation strategy starts by establishing model selection criteria based on different statistical descriptors calculated from the data residuals. Then, we perform cluster analysis considering the inverted resistivity models and the corresponding data residuals. Finally, we evaluate model uncertainties and residual distributions for each cluster. To illustrate the potential of our approach, we use a particle swarm optimization (PSO) algorithm to obtain an ensemble of 2D layer-based resistivity models from a synthetic data example and a field data set collected in Loon-Plage, France. Our strategy performs well for both synthetic and field data and allows us to extract different plausible model scenarios with their associated uncertainties and data residual distributions. Although we demonstrate our workflow using 2D ERT data and a PSObased inversion approach, the proposed strategy is general and can be adapted to analyze model ensembles generated from other kinds of geophysical data and using different global inversion approaches.}, language = {en} } @article{Lewandowski2022, author = {Lewandowski, Max}, title = {Hadamard states for bosonic quantum field theory on globally hyperbolic spacetimes}, series = {Journal of mathematical physics}, volume = {63}, journal = {Journal of mathematical physics}, number = {1}, publisher = {American Institute of Physics}, address = {Melville}, issn = {0022-2488}, doi = {10.1063/5.0055753}, pages = {34}, year = {2022}, abstract = {According to Radzikowski's celebrated results, bisolutions of a wave operator on a globally hyperbolic spacetime are of the Hadamard form iff they are given by a linear combination of distinguished parametrices i2(G˜aF-G˜F+G˜A-G˜R) in the sense of Duistermaat and H{\"o}rmander [Acta Math. 128, 183-269 (1972)] and Radzikowski [Commun. Math. Phys. 179, 529 (1996)]. Inspired by the construction of the corresponding advanced and retarded Green operator GA, GR as done by B{\"a}r, Ginoux, and Pf{\"a}ffle {Wave Equations on Lorentzian Manifolds and Quantization [European Mathematical Society (EMS), Z{\"u}rich, 2007]}, we construct the remaining two Green operators GF, GaF locally in terms of Hadamard series. Afterward, we provide the global construction of i2(G˜aF-G˜F), which relies on new techniques such as a well-posed Cauchy problem for bisolutions and a patching argument using Čech cohomology. This leads to global bisolutions of the Hadamard form, each of which can be chosen to be a Hadamard two-point-function, i.e., the smooth part can be adapted such that, additionally, the symmetry and the positivity condition are exactly satisfied.}, language = {en} } @article{TofeldeBufeTurowski2022, author = {Tofelde, Stefanie and Bufe, Aaron and Turowski, Jens M.}, title = {Hillslope Sediment Supply Limits Alluvial Valley Width}, series = {AGU Advances}, journal = {AGU Advances}, publisher = {American Geophysical Union (AGU); Wiley}, address = {Hoboken, New Jersey, USA}, issn = {2576-604X}, doi = {10.1029/2021AV000641}, pages = {20}, year = {2022}, abstract = {River-valley morphology preserves information on tectonic and climatic conditions that shape landscapes. Observations suggest that river discharge and valley-wall lithology are the main controls on valley width. Yet, current models based on these observations fail to explain the full range of cross-sectional valley shapes in nature, suggesting hitherto unquantified controls on valley width. In particular, current models cannot explain the existence of paired terrace sequences that form under cyclic climate forcing. Paired river terraces are staircases of abandoned floodplains on both valley sides, and hence preserve past valley widths. Their formation requires alternating phases of predominantly river incision and predominantly lateral planation, plus progressive valley narrowing. While cyclic Quaternary climate changes can explain shifts between incision and lateral erosion, the driving mechanism of valley narrowing is unknown. Here, we extract valley geometries from climatically formed, alluvial river-terrace sequences and show that across our dataset, the total cumulative terrace height (here: total valley height) explains 90\%-99\% of the variance in valley width at the terrace sites. This finding suggests that valley height, or a parameter that scales linearly with valley height, controls valley width in addition to river discharge and lithology. To explain this valley-width-height relationship, we reformulate existing valley-width models and suggest that, when adjusting to new boundary conditions, alluvial valleys evolve to a width at which sediment removal from valley walls matches lateral sediment supply from hillslope erosion. Such a hillslope-channel coupling is not captured in current valley-evolution models. Our model can explain the existence of paired terrace sequences under cyclic climate forcing and relates valley width to measurable field parameters. Therefore, it facilitates the reconstruction of past climatic and tectonic conditions from valley topography.}, language = {en} } @book{OPUS4-57691, title = {Linguistic hybridity}, series = {Studia Romanica}, journal = {Studia Romanica}, number = {232}, editor = {Hennemann, Anja and Meisnitzer, Benjamin}, publisher = {Universit{\"a}tsverlag Winter}, address = {Heidelberg}, isbn = {978-3-8253-4936-3}, pages = {229}, year = {2022}, abstract = {This volume deals with different linguistic phenomena representing grammaticalization and lexicalization processes and combines different approaches of contact linguistics and variational linguistics. It contains papers on clitic placement in Angolan Portuguese, on the use of subject pronouns in French, Brazilian Portuguese and Caribbean Spanish, on evidential marking in Paraguayan Spanish, on Paraguayan Guaran{\´i}, on evidentiality in different varieties of Spanish, on discourse markers in Latin America, on modal particles in Italian and their translation into German, on bilingual communities in Southern Brazil, on Spanish-German-Russian language contact and on Romance aspectual periphrases in contact with English progressives.}, language = {en} } @incollection{BoehmHennemannMeisnitzer2022, author = {B{\"o}hm, Ver{\´o}nica Julia and Hennemann, Anja and Meisnitzer, Benjamin}, title = {Language contact and the linguistic coding of evidentiality in varieties of Spanish in Latin America}, series = {Linguistic hybridity: contact-induced and cognitively motivated grammaticalization and lexicalization processes in Romance languages}, booktitle = {Linguistic hybridity: contact-induced and cognitively motivated grammaticalization and lexicalization processes in Romance languages}, publisher = {Universit{\"a}tsverlag Winter}, address = {Heidelberg}, isbn = {978-3-8253-4936-3}, pages = {117 -- 142}, year = {2022}, language = {en} } @incollection{HennemannMeisnitzer2022, author = {Hennemann, Anja and Meisnitzer, Benjamin}, title = {An introduction to contact-induced and cognitively motivated grammaticalization and lexicalization processes in Romance languages}, series = {Linguistic hybridity: contact-induced and cognitively motivated grammaticalization and lexicalization processes in Romance languages}, booktitle = {Linguistic hybridity: contact-induced and cognitively motivated grammaticalization and lexicalization processes in Romance languages}, publisher = {Heidelberg}, address = {Universit{\"a}tsverlag Winter}, isbn = {978-3-8253-4936-3}, pages = {7 -- 13}, year = {2022}, language = {en} } @article{KastiusSchlosser2022, author = {Kastius, Alexander and Schlosser, Rainer}, title = {Dynamic pricing under competition using reinforcement learning}, series = {Journal of revenue and pricing management}, volume = {21}, journal = {Journal of revenue and pricing management}, number = {1}, publisher = {Springer Nature Switzerland AG}, address = {Cham}, issn = {1476-6930}, doi = {10.1057/s41272-021-00285-3}, pages = {50 -- 63}, year = {2022}, abstract = {Dynamic pricing is considered a possibility to gain an advantage over competitors in modern online markets. The past advancements in Reinforcement Learning (RL) provided more capable algorithms that can be used to solve pricing problems. In this paper, we study the performance of Deep Q-Networks (DQN) and Soft Actor Critic (SAC) in different market models. We consider tractable duopoly settings, where optimal solutions derived by dynamic programming techniques can be used for verification, as well as oligopoly settings, which are usually intractable due to the curse of dimensionality. We find that both algorithms provide reasonable results, while SAC performs better than DQN. Moreover, we show that under certain conditions, RL algorithms can be forced into collusion by their competitors without direct communication.}, language = {en} } @article{AdairMcLaughlin2022, author = {Adair, Gigi and McLaughlin, Carly}, title = {Beyond humanitarianism}, series = {Narrating Flight and Asylum}, journal = {Narrating Flight and Asylum}, publisher = {Trier}, address = {WVT Wissenschaftlicher Verlag Trier}, isbn = {978-3-86821-965-4}, pages = {165 -- 182}, year = {2022}, language = {en} } @article{MiklashevskyFischerLindemann2022, author = {Miklashevsky, Alex and Fischer, Martin H. and Lindemann, Oliver}, title = {Spatial-numerical associations without a motor response? Grip force says 'Yes'}, series = {Acta Psychologica}, volume = {231}, journal = {Acta Psychologica}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-6297}, doi = {10.1016/j.actpsy.2022.103791}, pages = {1 -- 17}, year = {2022}, abstract = {In numerical processing, the functional role of Spatial-Numerical Associations (SNAs, such as the association of smaller numbers with left space and larger numbers with right space, the Mental Number Line hypothesis) is debated. Most studies demonstrate SNAs with lateralized responses, and there is little evidence that SNAs appear when no response is required. We recorded passive holding grip forces in no-go trials during number processing. In Experiment 1, participants performed a surface numerical decision task ("Is it a number or a letter?"). In Experiment 2, we used a deeper semantic task ("Is this number larger or smaller than five?"). Despite instruction to keep their grip force constant, participants' spontaneous grip force changed in both experiments: Smaller numbers led to larger force increase in the left than in the right hand in the numerical decision task (500-700 ms after stimulus onset). In the semantic task, smaller numbers again led to larger force increase in the left hand, and larger numbers increased the right-hand holding force. This effect appeared earlier (180 ms) and lasted longer (until 580 ms after stimulus onset). This is the first demonstration of SNAs with passive holding force. Our result suggests that (1) explicit motor response is not a prerequisite for SNAs to appear, and (2) the timing and strength of SNAs are task-dependent. (216 words).}, language = {en} }