@article{17390, author = {{Chantakit, Teanchai and Schlickriede, Christian and Sain, Basudeb and Meyer, Fabian and Weiss, Thomas and Chattham, Nattaporn and Zentgraf, Thomas}}, issn = {{2327-9125}}, journal = {{Photonics Research}}, number = {{9}}, pages = {{1435--1440}}, publisher = {{OSA}}, title = {{{All-dielectric silicon metalens for two-dimensional particle manipulation in optical tweezers}}}, doi = {{10.1364/prj.389200}}, volume = {{8}}, year = {{2020}}, } @inproceedings{17398, author = {{Turcanu, Ion and Engel, Thomas and Sommer, Christoph}}, booktitle = {{2019 IEEE Vehicular Networking Conference (VNC)}}, isbn = {{9781728145716}}, title = {{{Fog Seeding Strategies for Information-Centric Heterogeneous Vehicular Networks}}}, doi = {{10.1109/vnc48660.2019.9062816}}, year = {{2020}}, } @inproceedings{17405, author = {{Frank, Maximilian and Gausemeier, Juergen and Hennig-Cardinal von Widdern, Nils and Koldewey, Christian and Menzefricke, Joern Steffen and Reinhold, Jannik}}, booktitle = {{Proceedings of the ISPIM connects}}, publisher = {{International Society for Professional Innovation Management (ISPIM)}}, title = {{{A reference process for the Smart Service business: development and practical implications}}}, year = {{2020}}, } @inproceedings{17406, author = {{Becker, Julia-Kristin and Joachim, Klemens and Koldewey, Christian and Reinhold, Jannik and Dumitrescu, Roman}}, booktitle = {{Proceedings of the 2020 ISPIM Innovation Conference (Virtual) Event "Innovating in Times of Crisis"}}, publisher = {{ISPIM Innovation Conference}}, title = {{{Scaling Digital Business Models: A Case from the Automotive Industry}}}, year = {{2020}}, } @inproceedings{17407, author = {{Tornede, Alexander and Wever, Marcel Dominik and Hüllermeier, Eyke}}, booktitle = {{Discovery Science}}, title = {{{Extreme Algorithm Selection with Dyadic Feature Representation}}}, year = {{2020}}, } @inproceedings{17408, author = {{Hanselle, Jonas Manuel and Tornede, Alexander and Wever, Marcel Dominik and Hüllermeier, Eyke}}, booktitle = {{KI 2020: Advances in Artificial Intelligence}}, title = {{{Hybrid Ranking and Regression for Algorithm Selection}}}, year = {{2020}}, } @inbook{17411, abstract = {{Many dynamical systems possess symmetries, e.g. rotational and translational invariances of mechanical systems. These can be beneficially exploited in the design of numerical optimal control methods. We present a model predictive control scheme which is based on a library of precomputed motion primitives. The primitives are equivalence classes w.r.t. the symmetry of the optimal control problems. Trim primitives as relative equilibria w.r.t. this symmetry, play a crucial role in the algorithm. The approach is illustrated using an academic mobile robot example.}}, author = {{Flaßkamp, Kathrin and Ober-Blöbaum, Sina and Peitz, Sebastian}}, booktitle = {{Advances in Dynamics, Optimization and Computation}}, editor = {{Junge, Oliver and Schütze, Oliver and Froyland, Gary and Ober-Blöbaum, Sina and Padberg-Gehle, Kathrin}}, isbn = {{9783030512637}}, issn = {{2198-4182}}, publisher = {{Springer}}, title = {{{Symmetry in Optimal Control: A Multiobjective Model Predictive Control Approach}}}, doi = {{10.1007/978-3-030-51264-4_9}}, year = {{2020}}, } @inproceedings{17424, author = {{Tornede, Tanja and Tornede, Alexander and Wever, Marcel Dominik and Mohr, Felix and Hüllermeier, Eyke}}, booktitle = {{Proceedings of the ECMLPKDD 2020}}, title = {{{AutoML for Predictive Maintenance: One Tool to RUL Them All}}}, doi = {{10.1007/978-3-030-66770-2_8}}, year = {{2020}}, } @article{17426, abstract = {{The development of renewable energies and smart mobility has profoundly impacted the future of the distribution grid. An increasing bidirectional energy flow stresses the assets of the distribution grid, especially medium voltage switchgear. This calls for improved maintenance strategies to prevent critical failures. Predictive maintenance, a maintenance strategy relying on current condition data of assets, serves as a guideline. Novel sensors covering thermal, mechanical, and partial discharge aspects of switchgear, enable continuous condition monitoring of some of the most critical assets of the distribution grid. Combined with machine learning algorithms, the demands put on the distribution grid by the energy and mobility revolutions can be handled. In this paper, we review the current state-of-the-art of all aspects of condition monitoring for medium voltage switchgear. Furthermore, we present an approach to develop a predictive maintenance system based on novel sensors and machine learning. We show how the existing medium voltage grid infrastructure can adapt these new needs on an economic scale.}}, author = {{Hoffmann, Martin W. and Wildermuth, Stephan and Gitzel, Ralf and Boyaci, Aydin and Gebhardt, Jörg and Kaul, Holger and Amihai, Ido and Forg, Bodo and Suriyah, Michael and Leibfried, Thomas and Stich, Volker and Hicking, Jan and Bremer, Martin and Kaminski, Lars and Beverungen, Daniel and zur Heiden, Philipp and Tornede, Tanja}}, issn = {{1424-8220}}, journal = {{Sensors}}, title = {{{Integration of Novel Sensors and Machine Learning for Predictive Maintenance in Medium Voltage Switchgear to Enable the Energy and Mobility Revolutions}}}, doi = {{10.3390/s20072099}}, year = {{2020}}, } @article{17433, author = {{Wang, D. Q. and Reuter, Dirk and Wieck, A. D. and Hamilton, A. R. and Klochan, O.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, title = {{{Two-dimensional lateral surface superlattices in GaAs heterostructures with independent control of carrier density and modulation potential}}}, doi = {{10.1063/5.0009462}}, year = {{2020}}, } @article{17434, author = {{Kunnathully, Vinay S. and Riedl, Thomas and Trapp, Alexander and Langer, Timo and Reuter, Dirk and Lindner, Jörg K.N.}}, issn = {{0022-0248}}, journal = {{Journal of Crystal Growth}}, title = {{{InAs heteroepitaxy on nanopillar-patterned GaAs (111)A}}}, doi = {{10.1016/j.jcrysgro.2020.125597}}, year = {{2020}}, } @article{17435, author = {{Geier, M. and Freudenfeld, J. and Silva, J. T. and Umansky, V. and Reuter, Dirk and Wieck, A. D. and Brouwer, P. W. and Ludwig, S.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, title = {{{Electrostatic potential shape of gate-defined quantum point contacts}}}, doi = {{10.1103/physrevb.101.165429}}, year = {{2020}}, } @article{17436, abstract = {{The study of electron transport in low-dimensional systems is of importance, not only from a fundamental point of view, but also for future electronic and spintronic devices. In this context heterostructures containing a two-dimensional electron gas (2DEG) are a key technology. In particular GaAs/AlGaAs heterostructures, with a 2DEG at typically 100 nm below the surface, are widely studied. In order to explore electron transport in such systems, low-resistance ohmic contacts are required that connect the 2DEG to macroscopic measurement leads at the surface. Here we report on designing and measuring a dedicated device for unraveling the various resistance contributions in such contacts, which include pristine 2DEG series resistance, the 2DEG resistance under a contact, the contact resistance itself, and the influence of pressing a bonding wire onto a contact. We also report here a recipe for contacts with very low resistance values that remain below 10 Ω for annealing times between 20 and 350 s, hence providing the flexibility to use this method for materials with different 2DEG depths. The type of heating, temperature ramp rate and gas forming used for annealing is found to strongly influence the annealing process and hence the quality of the resulting contacts.}}, author = {{Javaid Iqbal, Muhammad and Reuter, Dirk and Wieck, Andreas Dirk and van der Wal, Caspar}}, issn = {{1286-0042}}, journal = {{The European Physical Journal Applied Physics}}, title = {{{Characterization of low-resistance ohmic contacts to a two-dimensional electron gas in a GaAs/AlGaAs heterostructure}}}, doi = {{10.1051/epjap/2020190202}}, year = {{2020}}, } @article{17437, author = {{Ebler, C. and Labud, P. A. and Rai, A. K. and Reuter, Dirk and Wieck, A. D. and Ludwig, A.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, title = {{{Electrical detection of excitonic states by time-resolved conductance measurements}}}, doi = {{10.1103/physrevb.101.125303}}, year = {{2020}}, } @article{17523, abstract = {{Compact and robust cold atom sources are increasingly important for quantum research, especially for transferring cutting-edge quantum science into practical applications. In this study, we report on a novel scheme that uses a metasurface optical chip to replace the conventional bulky optical elements used to produce a cold atomic ensemble with a single incident laser beam, which is split by the metasurface into multiple beams of the desired polarization states. Atom numbers ~107 and temperatures (about 35 μK) of relevance to quantum sensing are achieved in a compact and robust fashion. Our work highlights the substantial progress toward fully integrated cold atom quantum devices by exploiting metasurface optical chips, which may have great potential in quantum sensing, quantum computing, and other areas.}}, author = {{Zhu, Lingxiao and Liu, Xuan and Sain, Basudeb and Wang, Mengyao and Schlickriede, Christian and Tang, Yutao and Deng, Junhong and Li, Kingfai and Yang, Jun and Holynski, Michael and Zhang, Shuang and Zentgraf, Thomas and Bongs, Kai and Lien, Yu-Hung and Li, Guixin}}, issn = {{2375-2548}}, journal = {{Science Advances}}, number = {{31}}, publisher = {{American Association for the Advancement of Science}}, title = {{{A dielectric metasurface optical chip for the generation of cold atoms}}}, doi = {{10.1126/sciadv.abb6667}}, volume = {{6}}, year = {{2020}}, } @article{17578, author = {{Schweizer, Swetlana and Becker-Staines, Anna and Tröster, Thomas}}, issn = {{0956-053X}}, journal = {{Waste Management}}, pages = {{74--82}}, title = {{{Separation and reclamation of automotive hybrid structures made of metal and fibre-reinforced plastic}}}, doi = {{10.1016/j.wasman.2020.04.042}}, year = {{2020}}, } @article{17589, author = {{Sonnenrein, G. and Baumhögger, Elmar and Elsner, A. and Morbach, A. and Neukötter, M. and Paul, A. and Vrabec, J.}}, issn = {{0140-7007}}, journal = {{International Journal of Refrigeration}}, title = {{{Improving the performance of household refrigerating appliances through the integration of phase change materials in the context of the new global refrigerator standard IEC 62552:2015}}}, doi = {{10.1016/j.ijrefrig.2020.07.025}}, year = {{2020}}, } @unpublished{17605, abstract = {{Syntactic annotation of corpora in the form of part-of-speech (POS) tags is a key requirement for both linguistic research and subsequent automated natural language processing (NLP) tasks. This problem is commonly tackled using machine learning methods, i.e., by training a POS tagger on a sufficiently large corpus of labeled data. While the problem of POS tagging can essentially be considered as solved for modern languages, historical corpora turn out to be much more difficult, especially due to the lack of native speakers and sparsity of training data. Moreover, most texts have no sentences as we know them today, nor a common orthography. These irregularities render the task of automated POS tagging more difficult and error-prone. Under these circumstances, instead of forcing the POS tagger to predict and commit to a single tag, it should be enabled to express its uncertainty. In this paper, we consider POS tagging within the framework of set-valued prediction, which allows the POS tagger to express its uncertainty via predicting a set of candidate POS tags instead of guessing a single one. The goal is to guarantee a high confidence that the correct POS tag is included while keeping the number of candidates small. In our experimental study, we find that extending state-of-the-art POS taggers to set-valued prediction yields more precise and robust taggings, especially for unknown words, i.e., words not occurring in the training data.}}, author = {{Heid, Stefan Helmut and Wever, Marcel Dominik and Hüllermeier, Eyke}}, booktitle = {{Journal of Data Mining and Digital Humanities}}, publisher = {{episciences}}, title = {{{Reliable Part-of-Speech Tagging of Historical Corpora through Set-Valued Prediction}}}, year = {{2020}}, } @techreport{17703, abstract = {{Employing a unique sample of 2,849 tariff imposition announcements by and against the United States (U.S.) over the period from 2018 to 2019, this study analyzes the impact of recent tariff announcements on share prices from 859 U.S. companies. We provide evidence for negative (cumulative) average abnormal stock returns due to tariff announcements during a symmetric three-day event window. We suggest that stock market investors expect adverse impacts of tariff impositions, e.g. a decrease in the companies' future cash flows and a threat of retaliation. The negative wealth effects are observed irrespective of whether the Trump administration announces safeguard tariffs to protect domestic firms or a retaliation is declared by foreign countries. Moreover, building several subsamples, we find that the adverse impact is mostly driven by announcements involving China and is associated with a variety of sector, tariff, trade and firm characteristics.}}, author = {{Wengerek, Sascha Tobias}}, keywords = {{event study, international relations, protectionism, strategic trade policy, tariffs, trade conflict}}, pages = {{63}}, title = {{{Share price reactions to tariff imposition announcements in the Trump era - An event study of the trade conflict}}}, year = {{2020}}, } @article{17730, author = {{Ortmann, Regina and Pelster, Matthias and Wengerek, Sascha Tobias}}, issn = {{1544-6123}}, journal = {{Finance Research Letters}}, title = {{{COVID-19 and investor behavior}}}, doi = {{10.1016/j.frl.2020.101717}}, volume = {{37}}, year = {{2020}}, }