@inbook{36260,
  author       = {{Weber, Jutta}},
  booktitle    = {{Drone Imaginaries. The Power of Remote Vision}},
  editor       = {{Maurer, Kathrin and Graae, Andreas Immanuel}},
  pages        = {{167--179}},
  publisher    = {{Manchester University Press}},
  title        = {{{Artificial Intelligence and the Sociotechnical Imaginary: On Skynet, Self-Healing Swarms and Slaughterbots}}},
  year         = {{2021}},
}

@inbook{36257,
  author       = {{Weber, Jutta and Mayer, Katja}},
  booktitle    = {{Explorations in Digital Cultures}},
  editor       = {{Burkhardt, Marcus and Shnayien, Mary and Grashöfer, Katja}},
  publisher    = {{meson press}},
  title        = {{{From Optimizing Military Operations to Targeting Terrorist Networks: Social Network Analysis in Data-Driven Warfare}}},
  year         = {{2021}},
}

@inbook{36256,
  author       = {{Weber, Jutta}},
  booktitle    = {{In digitaler Gesellschaft. Neukonfigurationen zwischen Robotern, Algorithmen und Usern}},
  editor       = {{Braun, Kathrin and Kropp, Cordula}},
  pages        = {{213--222}},
  publisher    = {{transcript}},
  title        = {{{Human-Machine Learning und Digital Commons}}},
  year         = {{2021}},
}

@article{36545,
  abstract     = {{Due to the Corona crisis, German Higher Education Institutions had to close their campuses in March and lecturers had to teach online. To understand how the Corona crisis affected students, first this article explains the structural and social inequalities in the German higher education system, using Tinto's (1975; 1997) student engagement theory. Second, the concept of Bergman-Rosamond et al. (2020) is used to analyze the challenges that Corona has raised for students, including current surveys. We found that the closure of the social space campus (and the Corona crisis as a whole) particularly hit hard those students who had previously been affected by (intersectional) inequality. Therefore, to lessen the specific challenges associated with the ad hoc transition to digital studying, the creation of a digital community of learning can help. We demonstrate how such a community can be created by the example seminar, "Digital practices: an autoethnographic observation". During the seminar, students recorded their digital technology use in a journal, and we analyzed the diary entries using the collaborate autoethnography method. The seminar example shows that this method is well suited for the development of a community of learning as it not only places students in the spotlight but as students work together on a topic they get to know each other, and a basis of trust is created through peer-feedback. Therefore, it was important to have a digital space (in this case Mahara) where the exchange could take place. The continuous insight into the students’ "learning status" enabled the lecturer to promote the learning and provide individual assistance for the students.}},
  author       = {{Steinhardt, Isabel}},
  journal      = {{ISA Pedagogy Series}},
  keywords     = {{Intersectionality, inequality, gender, diversity, higher-education, crisis}},
  number       = {{1}},
  pages        = {{42--59}},
  publisher    = {{International Sociology Association}},
  title        = {{{Students in the spotlight: Using collaborative autoethnography to build a community of learning in the Corona crisis}}},
  volume       = {{1}},
  year         = {{2021}},
}

@techreport{36551,
  abstract     = {{The call for free access to research data and materials is becoming louder and louder from the political and scientific communities in Germany. More and more researchers are facing demands to open up qualitative research data for scientific purposes. They often have a general interest in sharing their data, but are unsure how to proceed. This handout was developed to provide an initial introduction to opening and sharing qualitative data. It was developed at a workshop held in Berlin in January 2020, organized by the research group „Digitization of Science“ of the Weizenbaum Institute, together with its associate researcher Dr. Isabel Steinhardt from the University of Kassel. The workshop involved staff from German research data centers as well as mentees and mentors from the Fellow Program Open Science who already have experience with Open Science, qualitative research, and interdisciplinary research. The handout is addressed primarily to qualitatively researching scientists in Germany. For this reason, it was initially written in German. One year later, we have now decided to translate the handout into English as well. The reasons are twofold: first, we want to make it accessible to researchers in Germany with little knowledge of German. Second, we also want to give interested people outside Germany an insight into the German system and the German discussion about opening up and sharing qualitative data. Due to the objectives and the history of its development, the handout focuses on the German context. This includes the literature references and further sources, and the references to research data centers as well as legal issues. We have deliberately not included a contextualization of the German situation in international discussions in order to keep the handout as short as possible.}},
  author       = {{Steinhardt, Isabel and Fischer, Caroline and Heimstädt, Maximilian and Hirsbrunner, Simon David and Ikiz-Akinci, Dilek and Kressin, Lisa and Kretzer, Susanne and Möllenkamp, Andreas and Portzelt, Maike and Rahal, Rima-Maria and Schimmler, Sonja and Wilke, René and Wünsche, Hannes}},
  pages        = {{20}},
  publisher    = {{Weizenbaum Institute for the Networked Society - The German Internet Institu}},
  title        = {{{Opening up and Sharing Data from Qualitative Research: A Primer}}},
  doi          = {{10.34669/WI.WS/17}},
  volume       = {{17}},
  year         = {{2021}},
}

@inbook{36557,
  abstract     = {{Anhand einer explorativen Studie in den Fächern Jura und Soziale Arbeit wird rekonstruiert welche Praktiken Studierende in Bezug auf digitale Technologien haben und ob digitale Praktiken im Studium existieren. Dazu wurden narrative Interviews mit sechs Studierenden geführt, die habitushermeneutisch ausgewertet wurden. Die Ergebnisse zeigen keine digitalen Praktiken in Bezug auf das Studium, wohingegen sich digitale Praktiken im alltäglichen Leben zeigen. Für das Studium zeigen sich unterschiedliche Praktiken in der Nutzung digitaler Technologien, die in Beziehung zu den Kapitalsorten stehen, die Studierende besitzen. Die explorativen Ergebnisse legen nahe, dass Studierende unterschiedliche Hilfestellungen in Bezug auf die Digitalisierung des Studiums benötigen, die in der Lehrplanung und -pädagogik berücksichtigt werden müssten.}},
  author       = {{Steinhardt, Isabel}},
  booktitle    = {{Entwicklungen im Feld der Hochschule}},
  editor       = {{Bremer, Helmut and Lange-Vester, Andrea}},
  isbn         = {{978-3-7799-5861-1}},
  pages        = {{213--226}},
  title        = {{{Digitale Praktiken und das Studium}}},
  year         = {{2021}},
}

@misc{30961,
  author       = {{Lammer, Christina}},
  publisher    = {{www.kibum.de (Thomas Boyken und Jörn Brüggemann),}},
  title        = {{{Andrea Karimé: Sterne im Kopf und ein unglaublicher Plan. Köln: Peter Hammer Verlag 2021}}},
  year         = {{2021}},
}

@article{25227,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>Quantum well (QW) heterostructures have been extensively used for the realization of a wide range of optical and electronic devices. Exploiting their potential for further improvement and development requires a fundamental understanding of their electronic structure. So far, the most commonly used experimental techniques for this purpose have been all-optical spectroscopy methods that, however, are generally averaging in momentum space. Additional information can be gained by angle-resolved photoelectron spectroscopy (ARPES), which measures the electronic structure with momentum resolution. Here we report on the use of extremely low-energy ARPES (photon energy ~ 7 eV) to increase depth sensitivity and access buried QW states, located at 3 nm and 6 nm below the surface of cubic-GaN/AlN and GaAs/AlGaAs heterostructures, respectively. We find that the QW states in cubic-GaN/AlN can indeed be observed, but not their energy dispersion, because of the high surface roughness. The GaAs/AlGaAs QW states, on the other hand, are buried too deep to be detected by extremely low-energy ARPES. Since the sample surface is much flatter, the ARPES spectra of the GaAs/AlGaAs show distinct features in momentum space, which can be reconducted to the band structure of the topmost surface layer of the QW structure. Our results provide important information about the samples’ properties required to perform extremely low-energy ARPES experiments on electronic states buried in semiconductor heterostructures.</jats:p>}},
  author       = {{Hajlaoui, Mahdi and Ponzoni, Stefano and Deppe, Michael and Henksmeier, Tobias and As, Donat Josef and Reuter, Dirk and Zentgraf, Thomas and Springholz, Gunther and Schneider, Claus Michael and Cramm, Stefan and Cinchetti, Mirko}},
  issn         = {{2045-2322}},
  journal      = {{Scientific Reports}},
  title        = {{{Extremely low-energy ARPES of quantum well states in cubic-GaN/AlN and GaAs/AlGaAs heterostructures}}},
  doi          = {{10.1038/s41598-021-98569-6}},
  volume       = {{11}},
  year         = {{2021}},
}

@inproceedings{44843,
  abstract     = {{Unsupervised blind source separation methods do not require a training phase
and thus cannot suffer from a train-test mismatch, which is a common concern in
neural network based source separation. The unsupervised techniques can be
categorized in two classes, those building upon the sparsity of speech in the
Short-Time Fourier transform domain and those exploiting non-Gaussianity or
non-stationarity of the source signals. In this contribution, spatial mixture
models which fall in the first category and independent vector analysis (IVA)
as a representative of the second category are compared w.r.t. their separation
performance and the performance of a downstream speech recognizer on a
reverberant dataset of reasonable size. Furthermore, we introduce a serial
concatenation of the two, where the result of the mixture model serves as
initialization of IVA, which achieves significantly better WER performance than
each algorithm individually and even approaches the performance of a much more
complex neural network based technique.}},
  author       = {{Boeddeker, Christoph and Rautenberg, Frederik and Haeb-Umbach, Reinhold}},
  booktitle    = {{ITG Conference on Speech Communication}},
  location     = {{Kiel}},
  title        = {{{A Comparison and Combination of Unsupervised Blind Source Separation  Techniques}}},
  year         = {{2021}},
}

@inproceedings{28259,
  author       = {{Boeddeker, Christoph and Zhang, Wangyou and Nakatani, Tomohiro and Kinoshita, Keisuke and Ochiai, Tsubasa and Delcroix, Marc and Kamo, Naoyuki and Qian, Yanmin and Haeb-Umbach, Reinhold}},
  booktitle    = {{ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)}},
  title        = {{{Convolutive Transfer Function Invariant SDR Training Criteria for Multi-Channel Reverberant Speech Separation}}},
  doi          = {{10.1109/icassp39728.2021.9414661}},
  year         = {{2021}},
}

@inproceedings{23998,
  author       = {{Schmalenstroeer, Joerg and Heitkaemper, Jens and Ullmann, Joerg and Haeb-Umbach, Reinhold}},
  booktitle    = {{29th European Signal Processing Conference (EUSIPCO)}},
  pages        = {{1--5}},
  title        = {{{Open Range Pitch Tracking for Carrier Frequency Difference Estimation from HF Transmitted Speech}}},
  year         = {{2021}},
}

@misc{48787,
  author       = {{Hartung, Olaf}},
  booktitle    = {{H-Soz-Kult}},
  publisher    = {{Clio-online - Historisches Fachinformationssystem e.V.}},
  title        = {{{Rezension von: Jörg van Norden, Thomas Must, Lars Deile, Peter Riedel, Susan Krause und Wanda Schürenberg (Hgg.): Geschichtsdidaktische Grundbegriffe. Ein Bilderbuch für Studium, Lehre und Beruf. Hannover 2020}}},
  year         = {{2021}},
}

@article{22528,
  abstract     = {{Due to the ad hoc nature of wireless acoustic sensor networks, the position of the sensor nodes is typically unknown. This contribution proposes a technique to estimate the position and orientation of the sensor nodes from the recorded speech signals. The method assumes that a node comprises a microphone array with synchronously sampled microphones rather than a single microphone, but does not require the sampling clocks of the nodes to be synchronized. From the observed audio signals, the distances between the acoustic sources and arrays, as well as the directions of arrival, are estimated. They serve as input to a non-linear least squares problem, from which both the sensor nodes’ positions and orientations, as well as the source positions, are alternatingly estimated in an iterative process. Given one set of unknowns, i.e., either the source positions or the sensor nodes’ geometry, the other set of unknowns can be computed in closed-form. The proposed approach is computationally efficient and the first one, which employs both distance and directional information for geometry calibration in a common cost function. Since both distance and direction of arrival measurements suffer from outliers, e.g., caused by strong reflections of the sound waves on the surfaces of the room, we introduce measures to deemphasize or remove unreliable measurements. Additionally, we discuss modifications of our previously proposed deep neural network-based acoustic distance estimator, to account not only for omnidirectional sources but also for directional sources. Simulation results show good positioning accuracy and compare very favorably with alternative approaches from the literature.}},
  author       = {{Gburrek, Tobias and Schmalenstroeer, Joerg and Haeb-Umbach, Reinhold}},
  issn         = {{1687-4722}},
  journal      = {{EURASIP Journal on Audio, Speech, and Music Processing}},
  title        = {{{Geometry calibration in wireless acoustic sensor networks utilizing DoA and distance information}}},
  doi          = {{10.1186/s13636-021-00210-x}},
  year         = {{2021}},
}

@inproceedings{23994,
  author       = {{Gburrek, Tobias and Schmalenstroeer, Joerg and Haeb-Umbach, Reinhold}},
  booktitle    = {{ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)}},
  title        = {{{Iterative Geometry Calibration from Distance Estimates for Wireless Acoustic Sensor Networks}}},
  doi          = {{10.1109/icassp39728.2021.9413831}},
  year         = {{2021}},
}

@inproceedings{23999,
  author       = {{Gburrek, Tobias and Schmalenstroeer, Joerg and Haeb-Umbach, Reinhold}},
  booktitle    = {{Speech Communication; 14th ITG-Symposium}},
  pages        = {{1--5}},
  title        = {{{On Source-Microphone Distance Estimation Using Convolutional Recurrent Neural Networks}}},
  year         = {{2021}},
}

@inproceedings{23997,
  author       = {{Chinaev, Aleksej and Enzner, Gerald and Gburrek, Tobias and Schmalenstroeer, Joerg}},
  booktitle    = {{29th European Signal Processing Conference (EUSIPCO)}},
  pages        = {{1--5}},
  title        = {{{Online Estimation of Sampling Rate Offsets in Wireless Acoustic Sensor Networks with Packet Loss}}},
  year         = {{2021}},
}

@misc{49017,
  author       = {{Moritz, Tilman}},
  booktitle    = {{sehepunkte}},
  number       = {{10}},
  title        = {{{A. Seidler, I. Monok (Hgg.): Reformation und Bücher. Zentren der Ideen – Zentren der Buchproduktion. Wiesbaden 2020}}},
  volume       = {{21}},
  year         = {{2021}},
}

@inproceedings{29304,
  abstract     = {{In this work we address disentanglement of style and content in speech signals. We propose a fully convolutional variational autoencoder employing two encoders: a content encoder and a style encoder. To foster disentanglement, we propose adversarial contrastive predictive coding. This new disentanglement method does neither need parallel data nor any supervision. We show that the proposed technique is capable of separating speaker and content traits into the two different representations and show competitive speaker-content disentanglement performance compared to other unsupervised approaches. We further demonstrate an increased robustness of the content representation against a train-test mismatch compared to spectral features, when used for phone recognition.}},
  author       = {{Ebbers, Janek and Kuhlmann, Michael and Cord-Landwehr, Tobias and Haeb-Umbach, Reinhold}},
  booktitle    = {{Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)}},
  pages        = {{3860–3864}},
  title        = {{{Contrastive Predictive Coding Supported Factorized Variational Autoencoder for Unsupervised Learning of Disentangled Speech Representations}}},
  year         = {{2021}},
}

@inproceedings{22894,
  abstract     = {{The first order optimality conditions of optimal control problems (OCPs) can
be regarded as boundary value problems for Hamiltonian systems. Variational or
symplectic discretisation methods are classically known for their excellent
long term behaviour. As boundary value problems are posed on intervals of
fixed, moderate length, it is not immediately clear whether methods can profit
from structure preservation in this context. When parameters are present,
solutions can undergo bifurcations, for instance, two solutions can merge and
annihilate one another as parameters are varied. We will show that generic
bifurcations of an OCP are preserved under discretisation when the OCP is
either directly discretised to a discrete OCP (direct method) or translated
into a Hamiltonian boundary value problem using first order necessary
conditions of optimality which is then solved using a symplectic integrator
(indirect method). Moreover, certain bifurcations break when a non-symplectic
scheme is used. The general phenomenon is illustrated on the example of a cut
locus of an ellipsoid.}},
  author       = {{Offen, Christian and Ober-Blöbaum, Sina}},
  issn         = {{2405-8963}},
  keywords     = {{optimal control, catastrophe theory, bifurcations, variational methods, symplectic integrators}},
  location     = {{Berlin, Germany}},
  pages        = {{334--339}},
  title        = {{{Bifurcation preserving discretisations of optimal control problems}}},
  doi          = {{https://doi.org/10.1016/j.ifacol.2021.11.099}},
  volume       = {{54(19)}},
  year         = {{2021}},
}

@article{47964,
  abstract     = {{In the last two decades, variably doped strontium barium niobate (SBN) has attracted a lot of scientific interest mainly due to its specific non-linear optical response. Comparably, the parental compound, i.e., undoped SBN, appears to be less studied so far. Here, two different cuts of single-crystalline nominally pure strontium barium niobate in the composition Sr0.61Ba0.39Nb2O6 (SBN61) are comprehensively studied and analyzed with regard to their photoconductive responses. We present conductance measurements under systematically varied illumination conditions along either the polar z-axis or perpendicular to it (x-cut). Apart from a pronounced photoconductance (PC) already under daylight and a large effect upon super-bandgap illumination in general, we observe (i) distinct spectral features when sweeping the excitation wavelength over the sub-bandgap region as then discussed in the context of deep and shallow trap states, (ii) extremely slow long-term relaxation for both light-on and light-off transients in the range of hours and days, (iii) a critical dependence of the photoresponse on the pre-illumination history of the sample, and (iv) a current–voltage hysteresis depending on both the illumination and the electrical-measurement conditions in a complex manner.}},
  author       = {{Beyreuther, Elke and Ratzenberger, Julius and Roeper, Matthias and Kirbus, Benjamin and Rüsing, Michael and Ivleva, Liudmila I. and Eng, Lukas M.}},
  issn         = {{2073-4352}},
  journal      = {{Crystals}},
  keywords     = {{Inorganic Chemistry, Condensed Matter Physics, General Materials Science, General Chemical Engineering}},
  number       = {{7}},
  publisher    = {{MDPI AG}},
  title        = {{{Photoconduction of Polar and Nonpolar Cuts of Undoped Sr0.61Ba0.39Nb2O6 Single Crystals}}},
  doi          = {{10.3390/cryst11070780}},
  volume       = {{11}},
  year         = {{2021}},
}