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See detailU wie Un
Heimböckel, Dieter UL

Article for general public (2012)

Detailed reference viewed: 67 (2 UL)
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See detailU-Lab: an out-of-the-box solution for any usability problem? A presentation on methodological and practical issues
Koenig, Vincent UL; van de Leemput, Cécile

Scientific Conference (2005)

Detailed reference viewed: 42 (0 UL)
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See detailUAS see-and-avoid strategy using a fuzzy logic controller optimized by Cross-Entropy in Scaling Factors and Membership Functions
Fu, Changhong; Olivares Mendez, Miguel Angel UL; Campoy, P. et al

in Unmanned Aircraft Systems (ICUAS), 2013 International Conference on (2013)

This work aims to develop a novel Cross-Entropy (CE) optimization-based fuzzy controller for Unmanned Aerial Monocular Vision-IMU System (UAMVIS) to solve the seeand-avoid problem using its accurate ... [more ▼]

This work aims to develop a novel Cross-Entropy (CE) optimization-based fuzzy controller for Unmanned Aerial Monocular Vision-IMU System (UAMVIS) to solve the seeand-avoid problem using its accurate autonomous localization information. The function of this fuzzy controller is regulating the heading of this system to avoid the obstacle, e.g. wall. In the Matlab Simulink-based training stages, the Scaling Factor (SF) is adjusted according to the specified task firstly, and then the Membership Function (MF) is tuned based on the optimized Scaling Factor to further improve the collison avoidance performance. After obtained the optimal SF and MF, 64% of rules has been reduced (from 125 rules to 45 rules), and a large number of real flight tests with a quadcopter have been done. The experimental results show that this approach precisely navigates the system to avoid the obstacle. To our best knowledge, this is the first work to present the optimized fuzzy controller for UAMVIS using Cross-Entropy method in Scaling Factors and Membership Functions optimization. [less ▲]

Detailed reference viewed: 137 (8 UL)
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See detailUAS See-and-Avoid using two different approaches of Fuzzy Control
Olivares Mendez, Miguel Angel UL; Mejias, Luis; Campoy, Pascual et al

in 2012 International Conference on Unmanned Aircraft Systems (ICUAS'12) (2012)

This work presents two UAS See and Avoid approaches using Fuzzy Control. We compare the performance of each controller when a Cross-Entropy method is applied to optimase the parameters for one of the ... [more ▼]

This work presents two UAS See and Avoid approaches using Fuzzy Control. We compare the performance of each controller when a Cross-Entropy method is applied to optimase the parameters for one of the controllers. Each controller receive information from an image processing frontend that detect and track targets in the environment. Visual information is then used under a visual servoing approach to perform autonomous avoidance. Experimental flight trials using a small quadrotor were performed to validate and compare the behaviour of both controllers. [less ▲]

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See detailUAV degradation identification for pilot notification using machine learning techniques
Manukyan, Anush UL; Olivares Mendez, Miguel Angel UL; Bissyande, Tegawendé François D Assise UL et al

in Proceedings of 21st IEEE International Conference on Emerging Technologies and Factory Automation ETFA 2016 (2016, September 06)

Unmanned Aerial Vehicles are currently investigated as an important sub-domain of robotics, a fast growing and truly multidisciplinary research field. UAVs are increasingly deployed in real-world settings ... [more ▼]

Unmanned Aerial Vehicles are currently investigated as an important sub-domain of robotics, a fast growing and truly multidisciplinary research field. UAVs are increasingly deployed in real-world settings for missions in dangerous environments or in environments which are challenging to access. Combined with autonomous flying capabilities, many new possibilities, but also challenges, open up. To overcome the challenge of early identification of degradation, machine learning based on flight features is a promising direction. Existing approaches build classifiers that consider their features to be correlated. This prevents a fine-grained detection of degradation for the different hardware components. This work presents an approach where the data is considered uncorrelated and, using machine learning <br />techniques, allows the precise identification of UAV’s damages. [less ▲]

Detailed reference viewed: 154 (22 UL)
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See detailUAV fleet area coverage with network connectivity constraint
Schleich, Julien UL; Panchapakesan, Athithyaa; Danoy, Grégoire UL et al

in Proceedings of the 11th ACM International Symposium on Mobility Management and Wireless Access (MobiWac'13) (2013)

Detailed reference viewed: 211 (13 UL)
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See detailUAV Fleet Mobility Model with Multiple Pheromones for Tracking Moving Observation Targets
Atten, Christophe UL; Chanouf, Loubna; Danoy, Grégoire UL et al

in 19th European Conference on Applications of Evolutionary Computation (EvoApplications) (2016)

Detailed reference viewed: 248 (34 UL)
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See detailUAV Multilevel Swarms for Situation Management
Rosalie, Martin UL; Danoy, Grégoire UL; Bouvry, Pascal UL et al

in Proceedings of the 2Nd Workshop on Micro Aerial Vehicle Networks, Systems, and Applications for Civilian Use (2016)

The development and usage of Unmanned Aerial Vehicles (UAVs) quickly increased in the last decades, mainly for military purposes. Nowadays, this type of technology is used in non-military contexts mainly ... [more ▼]

The development and usage of Unmanned Aerial Vehicles (UAVs) quickly increased in the last decades, mainly for military purposes. Nowadays, this type of technology is used in non-military contexts mainly for civil and environment protection: search & rescue teams, fire fighters, police officers, environmental scientific studies, etc. Although the technology for operating a single UAV is now mature, additional efforts are still necessary for using UAVs in fleets (or swarms). This position paper presents the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques). The challenges of this project consist of handling several fleets of UAVs (swarms) including communication, networking and positioning aspects. This motivates the development of novel multilevel cooperation algorithms which is an area that has not been widely explored, especially when autonomy is an additional challenge. Moreover, we will provide techniques to optimize communications for multilevel swarms. Finally, we will develop distributed and localized mobility management algorithms that will cope with conflicting objectives such as connectivity maintenance and geographical area coverage. [less ▲]

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See detailUAV Relay-Assisted Emergency Communications in IoT Networks: Resource Allocation and Trajectory Optimization
Tran Dinh, Hieu UL; Nguyen, van Dinh UL; Gautam, Sumit UL et al

E-print/Working paper (2020)

Unmanned aerial vehicle (UAV) communication has emerged as a prominent technology for emergency communications (e.g., natural disaster) in Internet of Things (IoT) networks to enhance the ability of ... [more ▼]

Unmanned aerial vehicle (UAV) communication has emerged as a prominent technology for emergency communications (e.g., natural disaster) in Internet of Things (IoT) networks to enhance the ability of disaster prediction, damage assessment, and rescue operations promptly. In this paper, a UAV is deployed as a flying base station (BS) to collect data from time-constrained IoT devices and then transfer the data to a ground gateway (GW). In general, the latency constraint at IoT users and the limited storage capacity of UAV highly hinder practical applications of UAV-assisted IoT networks. In this paper, full-duplex (FD) technique is adopted at the UAV to overcome these challenges. In addition, half-duplex (HD) scheme for UAV-based relaying is also considered to provide a comparative study between two modes (viz., FD and HD). Herein, a device is successfully served iff its data is collected by UAV and conveyed to GW within the flight time. In this context, we aim at maximizing the number of served IoT devices by jointly optimizing bandwidth and power allocation, as well as the UAV trajectory, while satisfying the requested timeout (RT) requirement of each device and the UAV’s limited storage capacity. The formulated optimization problem is troublesome to solve due to its non-convexity and combinatorial nature. Toward appealing applications, we first relax binary variables into continuous values and transform the original problem into a more computationally tractable form. By leveraging inner approximation framework, we derive newly approximated functions for non-convex parts and then develop a simple yet efficient iterative algorithm for its solutions. Next, we attempt to maximize the total throughput subject to the number of served IoT devices. Finally, numerical results show that the proposed algorithms significantly outperform benchmark approaches in terms of the number of served IoT devices and the amount of collected data. [less ▲]

Detailed reference viewed: 33 (2 UL)
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See detailUAV-Assisted Secure Communications in Terrestrial Cognitive Radio Networks: Joint Power Control and 3D Trajectory Optimization
Nguyen, X. Nguyen; Nguyen, van Dinh UL; Nguyen, Hieu V. et al

in IEEE Transactions on Vehicular Communications (in press)

This paper considers secure communications for an underlay cognitive radio network (CRN) in the presence of an external eavesdropper (Eve). The secrecy performance of CRNs is usually limited by the ... [more ▼]

This paper considers secure communications for an underlay cognitive radio network (CRN) in the presence of an external eavesdropper (Eve). The secrecy performance of CRNs is usually limited by the primary receiver’s interference power constraint. To overcome this issue, we propose to use an unmanned aerial vehicle (UAV) as a friendly jammer to interfere Eve in decoding the confidential message from the secondary transmitter (ST). Our goal is to jointly optimize the transmit power and UAV’s trajectory in the three-dimensional (3D) space to maximize the average achievable secrecy rate of the secondary system. The formulated optimization problem is nonconvex due to the nonconvexity of the objective and nonconvexity of constraints, which is very challenging to solve. To obtain a suboptimal but efficient solution to the problem, we first transform the original problem into a more tractable form and develop an iterative algorithm for its solution by leveraging the inner approximation framework. We further extend the proposed algorithm to the case of imperfect location information of Eve, where the average worst-case secrecy rate is considered as the objective function. Extensive numerical results are provided to demonstrate the merits of the proposed algorithms over existing approaches. [less ▲]

Detailed reference viewed: 46 (5 UL)
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See detailÜber Bildungskategorien in der „Community Music“. Überlegungen zur Ausbildung in der Blasmusik
Sagrillo, Damien UL

Presentation (2019, April 28)

Während das Konzept des formalen, nicht-formalen und informellen Lernens in seinen allgemeinen Orientierungen als bekannt vorausgesetzt werden kann, gilt dies weniger für die Musikpädagogik. Die ... [more ▼]

Während das Konzept des formalen, nicht-formalen und informellen Lernens in seinen allgemeinen Orientierungen als bekannt vorausgesetzt werden kann, gilt dies weniger für die Musikpädagogik. Die Sichtweise auf die Kategorien des Lernens im Allgemeinen, auf die Musikpädagogik und auf die Musikausübung von Amateuren im Besonderen wird Gegenstand der folgenden Zeilen sein. Darüber hinaus wird das Konzept der „community music“ (CM), für das sich in der deutschen Sprache keine geeignete Übersetzung findet, vorgestellt werden. Der Begriff „community music“ ist nicht an einer einzigen Definition festzumachen. Zunächst scheint es, als wäre er komplett losgelöst von traditionellen Methoden des Lernens formaler und nicht-formaler Art aufzufassen und eher der Kategorie informellen Lernens zuzuordnen. In neueren Ansätzen wird CM als Teil der Inklusion und Partizipation in einem assoziativen Umfeld gesehen und als Mittel, die Barriere zwischen traditioneller Musikpädagogik und den Anforderungen der musizierenden Menschen zu überwinden. Auf der anderen Seite versteht sich CM als Gegenentwurf zur musikalischen Hochkultur Das Konzept von CM eignet sich in besonderem Maße, um den Prozess der musikalischen Ausbildung junger Menschen darzustellen. Einerseits beginnt dieser oft mit einer Amateurphase, um später, für die talentiertesten, zum Berufsleben zu führen. Andererseits beschreibt CM die Ausbildung und den Weg junger Musiker hin zu Laienmusikorganisationen. Schließlich zeichnet CM das lebenslange Wirken von Amateurmusikern nach. In meinem Beitrag werde ich Definitionen für die drei Kategorien von Bildung in Bezug auf die Musikpädagogik anbieten. (Dabei kann nicht ignoriert werden, dass es im wissenschaftlichen Diskurs für den Aspekt der non-formalen Bildung im Zusammenhang mit Musik keinen Konsens gibt.) Schließlich wird, mithilfe der in Europa gängigen künstlerischen Praxis des Blasmusikwesens, die Verbindung der beiden Konzepte – Bildungskategorien und CM – exemplifiziert. [less ▲]

Detailed reference viewed: 96 (4 UL)
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See detailÜber das Gesetz: Zur juristischen Form bei Handke
Kohns, Oliver UL

in Gegenwartsliteratur : ein germanistisches Jahrbuch = a German studies yearbook (2013), 12

Der Beitrag fragt nach der Bedeutung von Begriffen wie »Gesetz« und »Gerechtigkeit« in den Texten Handkes. Eine schillernde Bedeutungsfülle nimmt das Konzept des »Gesetzes« an, es verweist aber zentral – ... [more ▼]

Der Beitrag fragt nach der Bedeutung von Begriffen wie »Gesetz« und »Gerechtigkeit« in den Texten Handkes. Eine schillernde Bedeutungsfülle nimmt das Konzept des »Gesetzes« an, es verweist aber zentral – wie im Vergleich mit Stifters »sanftem Gesetz« gezeigt werden soll – auf eine ästhetische Vorstellung von Gerechtigkeit (in der Wahrnehmung und Beschreibung der Wirklichkeit). Die Lektüre von Die Stunde der wahren Empfindung (1975) und Die Wiederholung (1986) soll zeigen, dass diese Vorstellung von Gerechtigkeit – als Suche nach dem Gesetz – auch die narrative Struktur von Handkes Texten prägen kann. Die »Serbien«-Texte Handkes zeigen schließlich, dass auch die explizit politischen Interventionen des Autors im Kontext der poetologischen Vorstellung von Gesetz und Gerechtigkeit verstanden werden müssen. [less ▲]

Detailed reference viewed: 138 (11 UL)
See detailÜber das Verhältnis von Identität, Sprache und Mehrsprachigkeit – mit einigen Anmerkungen zur Situation in Luxemburg
Hu, Adelheid UL

in Burwitz-Melzer, Eva; Königs, Frank; Riemer, Claudia (Eds.) Identität und Fremdsprachenlernen. Anmerkungen zu einer komplexen Beziehung. Arbeitspapiere der 33.Frühjahrskonferenz zur Erforschung der Fremdsprachenunterrichts (2013)

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See detailÜber den Einsatz eines Windschutzes bei gravimetrischen Messungen
Weigelt, Matthias UL; Schlesinger, R.

Scientific Conference (2010, October)

Detailed reference viewed: 38 (0 UL)
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See detailÜber den Zusammenhang zwischen dem physischen Selbstkonzept, der Bezugsnormorientierung und der Zielorientierung bei Grundschulkindern
Lohbeck, Annette; Tietjens, Maike; Bund, Andreas UL

in Wegner, Manfred; Brückner, Jan-Peter; Kratzenstein, Stefan (Eds.) Sportpsychologische Kompetenz und Verantwortung (2012, May)

Detailed reference viewed: 151 (2 UL)
See detailÜber die afrikanische Adaption von Kevin Rittbergers Kassandra oder Die Welt als Ende der Vorstellung in Togo
Nonoa, Koku Gnatuloma UL

in Assemboni, Amatso; Babka, Anna; Beck, Laura (Eds.) et al Postkolonialität denken – Spektren germanistischer Forschung in Togo (2017)

Detailed reference viewed: 32 (1 UL)
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See detailÜber die Ambivalenz des Teilens. Zur Rolle der Sharing Economy in Postwachstumsansätzen
Schulz, Christian UL

in Politische Ökologie (2020), 35(160), 66-71

Detailed reference viewed: 98 (8 UL)
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See detailÜber die Bedeutung des historischen Systemvergleichs für die Wirtschaftswissenschaften. Betrachtungen auf Makro-, Meso- und Mikroebene
Klump, Rainer UL

in Baar, L.; Petzina, D. (Eds.) Wirtschaftlicher Strukturwandel. Innovationen und regionaler Wandel im geteilten Deutschland nach 1945 (1999)

Detailed reference viewed: 34 (0 UL)