TY - CHAP A1 - Gehler, M. A1 - Ober-Blöbaum, S. A1 - Dachwald, Bernd T1 - Application of discrete mechanics and optimal control to spacecraft in non-keplerian motion around small solar system bodies T2 - Procceedings of the 60th International Astronautical Congress N2 - Prolonged operations close to small solar system bodies require a sophisticated control logic to minimize propellant mass and maximize operational efficiency. A control logic based on Discrete Mechanics and Optimal Control (DMOC) is proposed and applied to both conventionally propelled and solar sail spacecraft operating at an arbitrarily shaped asteroid in the class of Itokawa. As an example, stand-off inertial hovering is considered, recently identified as a challenging part of the Marco Polo mission. The approach is easily extended to stand-off orbits. We show that DMOC is applicable to spacecraft control at small objects, in particular with regard to the fact that the changes in gravity are exploited by the algorithm to optimally control the spacecraft position. Furthermore, we provide some remarks on promising developments. KW - Spacecraft Y1 - 2009 SN - 978-161567908-9 N1 - 60th International Astronautical Congress 2009, IAC 2009; Daejeon; South Korea; 12 October 2009 through 16 October 2009 SP - 1360 EP - 1371 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Abdurakhmanov, Aydemir A1 - Gumenyuk, Andrej T1 - Application of electron beam welding to fabrication of steel-aluminium dissimilar joint T2 - Beam technologies & laser application : proceedings of the VII international conference, Saint Petersburg, Sept. 18-21, 2012 Y1 - 2012 SP - 265 EP - 279 PB - Publ. House CY - Saint Petersburg ER - TY - CHAP A1 - Horikawa, Atsushi A1 - Okada, Kunio A1 - Uto, Takahiro A1 - Uchiyama, Yuta A1 - Wirsum, Manfred A1 - Funke, Harald A1 - Kusterer, Karsten T1 - Application of Low NOx Micro-mix Hydrogen Combustion to 2MW Class Industrial Gas Turbine Combustor T2 - Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan Y1 - 2019 SN - 978-4-89111-010-9 N1 - IGTC-2019-129 SP - 1 EP - 6 ER - TY - CHAP A1 - Horikawa, Atsushi A1 - Okada, Kunio A1 - Kazari, Masahide A1 - Funke, Harald A1 - Keinz, Jan A1 - Kusterer, Karsten A1 - Haj Ayed, Anis T1 - Application of Low NOx Micro-Mix Hydrogen Combustion to Industrial Gas Turbine Combustor and Conceptual Design T2 - Proceedings of International Gas Turbine Congress 2015 Tokyo November 15-20, 2015, Tokyo, Japan Y1 - 2015 SN - 978-4-89111-008-6 N1 - IGTC15-0238 SP - 141 EP - 146 ER - TY - CHAP A1 - Dilthey, Ulrich A1 - Schleser, Markus A1 - Möller, M. A1 - Weichhold, O. ED - Hegger, Josef T1 - Application of polymers in textile reinforced concrete : from the interface to construction elements T2 - Textile reinforced concrete : proceedings of the 1. International RILEM Conference, held at the RWTH Aachen, September 6/7, 2006. (RILEM proceedings ; 50) Y1 - 2006 SN - 2-912143-97-7 SP - 55 EP - 64 PB - RILEM Publ. CY - Bagneux ER - TY - CHAP A1 - Wittig, M. A1 - Rütters, René A1 - Bragard, Michael ED - Reiff-Stephan, Jörg ED - Jäkel, Jens ED - Schwarz, André T1 - Application of RL in control systems using the example of a rotatory inverted pendulum T2 - Tagungsband AALE 2024 : Fit für die Zukunft: praktische Lösungen für die industrielle Automation N2 - In this paper, the use of reinforcement learning (RL) in control systems is investigated using a rotatory inverted pendulum as an example. The control behavior of an RL controller is compared to that of traditional LQR and MPC controllers. This is done by evaluating their behavior under optimal conditions, their disturbance behavior, their robustness and their development process. All the investigated controllers are developed using MATLAB and the Simulink simulation environment and later deployed to a real pendulum model powered by a Raspberry Pi. The RL algorithm used is Proximal Policy Optimization (PPO). The LQR controller exhibits an easy development process, an average to good control behavior and average to good robustness. A linear MPC controller could show excellent results under optimal operating conditions. However, when subjected to disturbances or deviations from the equilibrium point, it showed poor performance and sometimes instable behavior. Employing a nonlinear MPC Controller in real time was not possible due to the high computational effort involved. The RL controller exhibits by far the most versatile and robust control behavior. When operated in the simulation environment, it achieved a high control accuracy. When employed in the real system, however, it only shows average accuracy and a significantly greater performance loss compared to the simulation than the traditional controllers. With MATLAB, it is not yet possible to directly post-train the RL controller on the Raspberry Pi, which is an obstacle to the practical application of RL in a prototyping or teaching setting. Nevertheless, RL in general proves to be a flexible and powerful control method, which is well suited for complex or nonlinear systems where traditional controllers struggle. KW - Rotatory Inverted Pendulum KW - MPC KW - LQR KW - PPO KW - Reinforcement Learning Y1 - 2024 SN - 978-3-910103-02-3 U6 - http://dx.doi.org/10.33968/2024.53 N1 - 20. AALE-Konferenz. Bielefeld, 06.03.-08.03.2024. (Tagungsband unter https://doi.org/10.33968/2024.29) SP - 241 EP - 248 PB - le-tex publishing services GmbH CY - Leipzig ER - TY - CHAP A1 - Bung, Daniel B. A1 - Valero, Daniel ED - Crookston, B. ED - Tullis, B. T1 - Application of the optical flow method to velocity determination in hydraulic structure models BT - Session 11: Fish passage and shiplocks T2 - Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016 Y1 - 2016 SN - 978-1-884575-75-4 U6 - http://dx.doi.org/10.15142/T3150628160853 SP - 223 EP - 232 ER - TY - CHAP A1 - Darveniza, M. A1 - Flisowski, Z. A1 - Kern, Alexander A1 - Landers, E.-U. A1 - LoPiparo, G. A1 - Mazzetti, C. A1 - Rousseau, A. A1 - Sherlock, J. T1 - Application problems of the probabilistic approach to the assessment of risk for structures and services N2 - The paper deals with the development of the probabilistic approach to the assessment of risk due to lightning. Sources of damage, types of damage and types of loss are defined and, accordingly, the procedure for risk analysis and the way of assessment of different risk components is proposed. The way to evaluate the influence of different protection measures (lightning protection system; shielding of structure, cables and equipment; routing of internal wiring; surge protective device) in reducing such probabilities is considered. The paper has been prepared within the framework of the activity of IEC TC81-WG9/CLC TC81-WG4 directed to prepare the draft IEC 62305-2 Risk Management, in cooperation with the Secretary of IEC/CLC TC81. KW - Blitzschutz KW - Risikoabwägung KW - Lightning protection system KW - risk assessment KW - protection measures Y1 - 2002 ER - TY - CHAP A1 - Hellmanns, Mark A1 - Fischer, F. A1 - Dilger, Klaus T1 - Applikation und Einsatz von faserverstärkten Klebstoffen im Bauwesen T2 - Tagungsband / 13. Kolloquium Gemeinsame Forschung in der Klebtechnik : 26. und 27. Februar 2013, Frankfurt am Main Y1 - 2013 SP - 61 EP - 62 PB - DECHEMA CY - Frankfurt a.M. ER - TY - CHAP A1 - Hellmanns, Mark A1 - Fischer, F. A1 - Dilger, K. A1 - Wittor, B. A1 - Hildebrand, J. A1 - Werner, F. T1 - Applikation und Einsatz von faserverstärkten Klebstoffen im Bauwesen abgeschlossenes IGF-Projekt Nr. 16956 B (DVS 08.072, Laufzeit 01.02.2011 - 31.01.2013) T2 - Tagungsband / 14. Kolloquium Gemeinsame Forschung in der Klebtechnik : 18. und 19. Februar 2014, DECHEMA-Haus, Frankfurt am Main Y1 - 2014 SP - 26 EP - 27 ER -