@article{WojciechowskiPogscheba2022, author = {Wojciechowski, Manfred and Pogscheba, Patrick}, title = {Building a COVID-Safe Navigation App Using a Meta-Model Based Context Server}, series = {sensors}, volume = {22}, journal = {sensors}, number = {24}, publisher = {MDPI}, issn = {1424-8220}, doi = {10.3390/s22249890}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-39570}, pages = {1 -- 14}, year = {2022}, abstract = {Building context-aware applications is an already widely researched topic. It is our belief that context awareness has the potential to supplement the Internet of Things, when a suitable methodology including supporting tools will ease the development of context-aware applications. We believe that a meta-model based approach can be key to achieving this goal. In this paper, we present our meta-model based methodology, which allows us to define and build application-specific context models and the integration of sensor data without any programming. We describe how that methodology is applied with the implementation of a relatively simple context-aware COVID-safe navigation app. The outcome showed that programmers with no experience in context-awareness were able to understand the concepts easily and were able to effectively use it after receiving a short training. Therefore, context-awareness is able to be implemented within a short amount of time. We conclude that this can also be the case for the development of other context-aware applications, which have the same context-awareness characteristics. We have also identified further optimization potential, which we will discuss at the conclusion of this article.}, language = {en} } @article{WohlersMuellerBraun2022, author = {Wohlers, Luis Constantin and M{\"u}ller, Patrick and Braun, Alexander}, title = {Original image noise reconstruction for spatially-varying filtered driving scenes}, series = {Electronic Imaging: Society for Imaging Science and Technology}, volume = {34}, journal = {Electronic Imaging: Society for Imaging Science and Technology}, number = {16}, publisher = {Society for Imaging Sciences and Technology}, issn = {2470-1173}, doi = {10.2352/EI.2022.34.16.AVM-214}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-41479}, pages = {1 -- 7}, year = {2022}, language = {en} } @article{WittpahlDeeganBlacketal.2021, author = {Wittpahl, Christian and Deegan, Brian and Black, Bob and Braun, Alexander}, title = {An analytic-numerical image flicker study to test novel flicker metrics}, series = {Electronic Imaging: Society for Imaging Science and Technology}, journal = {Electronic Imaging: Society for Imaging Science and Technology}, number = {17}, publisher = {Society for Imaging Science and Technology}, issn = {2470-1173}, doi = {10.2352/ISSN.2470-1173.2021.17.AVM-183}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-35671}, pages = {1 -- 8}, year = {2021}, language = {en} } @inproceedings{vonBergSchwoererPrinzetal.2023, author = {von Berg, Markus and Schw{\"o}rer, Paul and Prinz, Lukas and Steffens, Jochen}, title = {Analysis of physical and perceptual properties of room impulse responses: development of an online tool}, series = {Forum Acusticuum 2023: 10th Convention of European Acoustics Association, Turin, Italy, 11th-15th September 2023}, booktitle = {Forum Acusticuum 2023: 10th Convention of European Acoustics Association, Turin, Italy, 11th-15th September 2023}, publisher = {EAA}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-41955}, pages = {8}, year = {2023}, abstract = {Over the past decades, research in room acoustics has established several derivative measures of an impulse response, some of which are incorporated in the ISO 3382 standards. These parameters intend to represent perceptual qualities, but were developed without a consistent modeling of room acoustical perception. More recent research proposed comprehensive inventories of room acoustic perception that are purely based on evaluations by human subjects, such as the Room Acoustical Quality Index (RAQI). In this work RA-QI scores acquired for 70 room impulse responses were predicted from room acoustical parameters. Except for Reverberance, the prediction of RAQI factors performed rather poor. In most cases, the sound source had a greater impact on RAQI scores. All analyses are published in an online tool, where users can upload omnidirectional and binaural impulse responses, and instantly obtain and visualize several physical descriptors, as well as predicted RAQI scores for three different sound sources. So far, acceptable prediction accuracy is achieved for Reverberance, Strength, Irregular Decay, Clarity and Intimacy. Larger data sets of evaluated impulse responses are required to improve the model performance and enable reliable predictions of room acoustical quality. Therefore, the administration of RAQI evaluations within the website is currently being developed.}, language = {en} } @inproceedings{vonBergPrinzSteffens2022, author = {von Berg, Markus and Prinz, Lukas and Steffens, Jochen}, title = {Comparing individual perception of timbre and reverberance}, address = {Gyeoungju, S{\"u}dkorea}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-38706}, pages = {5}, year = {2022}, abstract = {Room reverberation alters the spatial impression and timbre of a sound by modulating its spectral and temporal characteristics. Thus, we argue that, on a perceptual level, reverberation basically breaks down into interaural differences and spectro-temporal cues and that the separation of a perceived timbre into a sound source and a surrounding room is a purely cognitive process. To investigate the connection between the perception of reverberation cues and timbre analysis, the sensitivity for changes in reverberation was compared to timbre perception abilities. The Timbre Perception Test was used to measure the perception of the temporal envelope, spectral centroid, and spectral flux of artificial sounds. Sensitivity for changes in reverberation time was tested with a discrimination task using speech and noise with speech-alike spectral and temporal envelopes as source signals. Musical and acoustical expertise was assessed through the Goldsmiths Musical Sophistication Index and self-reports on experience with and knowledge of acoustics. There was a considerable correlation between timbre and reverberance perception ability, but timbre perception and academic experience predicted only 41\% of the variance in reverberance perception. Still, perception abilities related to similar acoustical phenomena seem to be better indicators of listening skills than self-reports on acoustical or musical expertise.}, language = {en} } @techreport{Vogel2017, author = {Vogel, Peter}, title = {Investing as Random Trial}, series = {Trading}, journal = {Trading}, number = {1}, publisher = {Hochschule D{\"u}sseldorf}, address = {D{\"u}sseldorf}, issn = {2567-2347}, doi = {10.20385/2567-2347/2017.1}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-11118}, pages = {39}, year = {2017}, abstract = {We introduce an investment algorithm for a market of individual securities. The investment algorithm is derived from constraints depending on investment parameters in order to limit the risk and to take into account an individual investor. One constraint is devoted to trading costs. Purchased securities are selected randomly among securities that meet the buy condition, making trading a random trial. Simulations with historical price data are demonstrated for a simple example: The buy condition is evaluated on the basis of the price relationship for two subsequent trading days and the sales condition is defined by holding securities only for one day. A trading expert evaluates the expected return for the investment algorithm with respect to the random selection. Thus, the expert informs precisely on how many market players perform using the same investment algorithm. Its findings are for a parametrized set of buy conditions simultaneously, which makes a trading expert a valuable tool for theorists as well as for practitioners. In our example, the trading expert demonstrated clearly a significant mean reversion effect for a horizon of one day.}, language = {en} } @misc{Vogel2018, author = {Vogel, Peter}, title = {Marktdaten}, series = {Trading}, journal = {Trading}, publisher = {Hochschule D{\"u}sseldorf}, address = {D{\"u}sseldorf}, issn = {2567-2347}, doi = {10.20385/2567-2347/2017.1/1}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-15015}, year = {2018}, abstract = {Die in der Schriftenreihe Trading verwendeten Forschungsdaten beinhalten historische Kursdaten, geliefert von Lenz+Partner AG (Deutschland), f{\"u}r eine Auswahl an Aktien. Die Datei „FEBRDUSA_1" zeigt diese Auswahl in Form der deutschen Wertpapierkennnummer (Spalte „Titel"), des Handelszeitraums (Spalten „Beginn" und „Ende") und des Aktiennamens. Kursdaten sind in dieser Datei nicht enthalten, sondern liegen in einer umfangreichen Datenbank vor. Die Marktdaten umfassen 867 Aktien und sind das Ergebnis eines im Jahr 2015 durchgef{\"u}hrten Auswahlprozesses mit dem Ziel, Datenqualit{\"a}t und Handelbarkeit der Aktien zu verbessern. Es wurden folgende Bedingungen gefordert: - Die Aktien werden an der Frankfurter B{\"o}rse gehandelt. - Sie sind in einem der deutschen Aktienindizes DAX, MDAX, TECDAX, SDAX, HDAX, CDAX, Technology All Share, Prime All Share und GEX oder in den amerikanischen Aktienindizes S\&P 500 oder Nasdaq 100 gelistet. - Die Kursdaten der in Frankfurt gehandelten Aktien enden nicht vor dem Jahr 2014. - Der (unbereinigte) Er{\"o}ffnungskurs Ende 2013 betr{\"a}gt mindestens 1 EUR. Diese Bedingung soll dazu beitragen, das Handeln von „penny stocks" zu verhindern. Die vorliegende Marktdefinition resultierte in 867 Aktien, die fr{\"u}hestens am 11. Dezember 2014 enden, sodass eine Auswertung der Marktdaten mit vollst{\"a}ndigen Kurswerten bis zu diesem Zeitpunkt m{\"o}glich ist. Der Markt ist groß genug, um interessante Kaufbedingungen mit einer ausreichend großen Anzahl an Kaufkandidaten zu untersuchen.}, language = {en} } @article{VersuemerSteffensBlaettermannetal.2020, author = {Vers{\"u}mer, Siegbert and Steffens, Jochen and Bl{\"a}ttermann, Patrick and Becker-Schweitzer, J{\"o}rg}, title = {Modelling evaluations of low-level sounds in everyday situations using linear machine learning for variable selection}, series = {Frontiers in Psychology}, volume = {11}, journal = {Frontiers in Psychology}, publisher = {Frontiers}, issn = {1664-1078}, doi = {10.3389/fpsyg.2020.570761}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-23779}, year = {2020}, language = {en} } @techreport{vanRiessenvandenBrink2020, author = {van Rießen, Anne and van den Brink, Henning}, title = {From impacts to benefits: User research as a change of perspective for studies on the practice of drama education}, address = {D{\"u}sseldorf}, issn = {2509-6958}, doi = {10.20385/2509-6958/2020.6}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-21273}, pages = {17}, year = {2020}, abstract = {This essay looks at the potentials and limitations of user research for studies on the practice of drama education. To date, this field has been dominated by impact studies. After illustrating the blind spots that are created by taking this research approach to the practice of drama education, we will present the user research perspective and look at the opportunities that it provides to generate new, differentiated knowledge. User research makes it possible to illuminate the processes of acquiring and using knowledge in terms of its delivery. It also provides a potential framework of analysis for placing these processes in the delivery context, which includes subjective learning types, relevance and institutional and social conditions. This expanded perspective will make it possible to identify the factors that foster and limit benefits and reflect them in practice.}, subject = {Theaterp{\"a}dagogik}, language = {en} } @inproceedings{TiatorGeigerGrimm2020, author = {Tiator, Marcel and Geiger, Christian and Grimm, Paul}, title = {Point Cloud Segmentation with Deep Reinforcement Learning}, series = {ECAI 2020: 24th European Conference on Artificial Intelligence, 29 August-8 September 2020, Santiago De Compostela, Spain - Including 10th Conference on Prestigious Applications of Artificial Intellig}, booktitle = {ECAI 2020: 24th European Conference on Artificial Intelligence, 29 August-8 September 2020, Santiago De Compostela, Spain - Including 10th Conference on Prestigious Applications of Artificial Intellig}, editor = {Dilkina, B. and Catala, A. and Giacomo, G. De}, publisher = {IOS Press}, isbn = {978-1-64368-100-9}, doi = {10.3233/FAIA200417}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-30872}, pages = {2768 -- 2775}, year = {2020}, language = {en} }