@inproceedings{RosinHenneboehlButenweg2015, author = {Rosin, J. and Henneb{\"o}hl, B. and Butenweg, Christoph}, title = {Globale Stabilit{\"a}tsanalysen zylindrischer, seismisch belasteter Tanks auf numerischer Grundlage}, series = {Erdbeben und bestehende Bauten : 14. D-A-C-H Tagung 20.08. - 21.08.2015, ETH Z{\"u}rich. (Dokumentation / SIA ; D 0255)}, booktitle = {Erdbeben und bestehende Bauten : 14. D-A-C-H Tagung 20.08. - 21.08.2015, ETH Z{\"u}rich. (Dokumentation / SIA ; D 0255)}, publisher = {SGEB}, address = {Z{\"u}rich}, organization = {D-A-C-H Tagung <14, 2015, Z{\"u}rich>}, isbn = {978-3-03732-060-0}, pages = {173 -- 180}, year = {2015}, language = {de} } @inproceedings{MatareSchifferFerrein2019, author = {Matar{\´e}, Victor and Schiffer, Stefan and Ferrein, Alexander}, title = {golog++ : An integrative system design}, series = {CogRob 2018. Cognitive Robotics Workshop : Proceedings of the 11th Cognitive Robotics Workshop 2018 co-located with 16th International Conference on Principles of Knowledge Representation and Reasoning (KR 2018) Tempe, AZ, USA, October 27th, 2018}, booktitle = {CogRob 2018. Cognitive Robotics Workshop : Proceedings of the 11th Cognitive Robotics Workshop 2018 co-located with 16th International Conference on Principles of Knowledge Representation and Reasoning (KR 2018) Tempe, AZ, USA, October 27th, 2018}, editor = {Steinbauer, Gerald and Ferrein, Alexander}, issn = {1613-0073}, pages = {29 -- 35}, year = {2019}, language = {en} } @inproceedings{ChajanSchulteTiggesRekeetal.2021, author = {Chajan, Eduard and Schulte-Tigges, Joschua and Reke, Michael and Ferrein, Alexander and Matheis, Dominik and Walter, Thomas}, title = {GPU based model-predictive path control for self-driving vehicles}, series = {IEEE Intelligent Vehicles Symposium (IV)}, booktitle = {IEEE Intelligent Vehicles Symposium (IV)}, publisher = {IEEE}, address = {New York, NY}, isbn = {978-1-7281-5394-0}, doi = {10.1109/IV48863.2021.9575619}, pages = {1243 -- 1248}, year = {2021}, abstract = {One central challenge for self-driving cars is a proper path-planning. Once a trajectory has been found, the next challenge is to accurately and safely follow the precalculated path. The model-predictive controller (MPC) is a common approach for the lateral control of autonomous vehicles. The MPC uses a vehicle dynamics model to predict the future states of the vehicle for a given prediction horizon. However, in order to achieve real-time path control, the computational load is usually large, which leads to short prediction horizons. To deal with the computational load, the control algorithm can be parallelized on the graphics processing unit (GPU). In contrast to the widely used stochastic methods, in this paper we propose a deterministic approach based on grid search. Our approach focuses on systematically discovering the search area with different levels of granularity. To achieve this, we split the optimization algorithm into multiple iterations. The best sequence of each iteration is then used as an initial solution to the next iteration. The granularity increases, resulting in smooth and predictable steering angle sequences. We present a novel GPU-based algorithm and show its accuracy and realtime abilities with a number of real-world experiments.}, language = {en} } @inproceedings{SchulteSchwagerNoureldinetal.2023, author = {Schulte, Jonas and Schwager, Christian and Noureldin, Kareem and May, Martin and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Gradient controlled startup procedure of a molten-salt power-to-heat energy storage plant based on dynamic process simulation}, series = {SolarPACES: Solar Power \& Chemical Energy Systems}, booktitle = {SolarPACES: Solar Power \& Chemical Energy Systems}, number = {2815 / 1}, publisher = {AIP conference proceedings / American Institute of Physics}, address = {Melville, NY}, isbn = {978-0-7354-4623-6}, issn = {1551-7616 (online)}, doi = {10.1063/5.0148741}, pages = {9 Seiten}, year = {2023}, abstract = {The integration of high temperature thermal energy storages into existing conventional power plants can help to reduce the CO2 emissions of those plants and lead to lower capital expenditures for building energy storage systems, due to the use of synergy effects [1]. One possibility to implement that, is a molten salt storage system with a powerful power-to-heat unit. This paper presents two possible control concepts for the startup of the charging system of such a facility. The procedures are implemented in a detailed dynamic process model. The performance and safety regarding the film temperatures at heat transmitting surfaces are investigated in the process simulations. To improve the accuracy in predicting the film temperatures, CFD simulations of the electrical heater are carried out and the results are merged with the dynamic model. The results show that both investigated control concepts are safe regarding the temperature limits. The gradient controlled startup performed better than the temperature-controlled startup. Nevertheless, there are several uncertainties that need to be investigated further.}, language = {en} } @inproceedings{KraftMeyerNagl2002, author = {Kraft, Bodo and Meyer, Oliver and Nagl, Manfred}, title = {Graph technology support for conceptual design in civil engineering}, isbn = {3-18-318004-9}, year = {2002}, abstract = {In: Advances in intelligent computing in engineering : proceedings of the 9.International EG-ICE Workshop ; Darmstadt, (01 - 03 August) 2002 / Martina Schnellenbach-Held ... (eds.) . - D{\"u}sseldorf: VDI-Verl., 2002 .- Fortschritt-Berichte VDI, Reihe 4, Bauingenieurwesen ; 180 ; S. 1-35 The paper describes a novel way to support conceptual design in civil engineering. The designer uses semantical tools guaranteeing certain internal structures of the design result but also the fulfillment of various constraints. Two different approaches and corresponding tools are discussed: (a) Visually specified tools with automatic code generation to determine a design structure as well as fixing various constraints a design has to obey. These tools are also valuable for design knowledge specialist. (b) Extensions of existing CAD tools to provide semantical knowledge to be used by an architect. It is sketched how these different tools can be combined in the future. The main part of the paper discusses the concepts and realization of two prototypes following the two above approaches. The paper especially discusses that specific graphs and the specification of their structure are useful for both tool realization projects.}, subject = {CAD}, language = {en} } @inproceedings{KraftRetkowitz2006, author = {Kraft, Bodo and Retkowitz, Daniel}, title = {Graph Transformations for Dynamic Knowledge Processing}, year = {2006}, abstract = {In: Proceedings of the 39th Annual Hawaii International Conference on System Sciences, 2006. HICSS '06 http://dx.doi.org/10.1109/HICSS.2006.200 The conceptual design phase at the beginning of the building construction process is not adequately supported by any CAD-tool. Conceptual design support needs regarding two aspects: first, the architect must be able to develop conceptual sketches that provide abstraction from constructive details. Second, conceptually relevant knowledge should be available to check these conceptual sketches. The paper deals with knowledge to formalize for conceptual design. To enable domain experts formalizing knowledge, a graph-based specification is presented that allows the development of a domain ontology and design rules specific for one class of buildings at runtime. The provided tool support illustrates the introduced concepts and demonstrates the consistency analysis between knowledge and conceptual design.}, subject = {CAD}, language = {de} } @inproceedings{LorenzAltherrPelz2019, author = {Lorenz, Imke-Sophie B. and Altherr, Lena and Pelz, Peter F.}, title = {Graph-theoretic resilience analysis of a water distribution system's topology}, series = {World Congress on Resilience, Reliability and Asset Management 2019}, booktitle = {World Congress on Resilience, Reliability and Asset Management 2019}, pages = {106 -- 109}, year = {2019}, abstract = {Water suppliers are faced with the great challenge of achieving high-quality and, at the same time, low-cost water supply. In practice, the focus is set on the most beneficial maintenance measures and/or capacity adaptations of existing water distribution systems (WDS). Since climatic and demographic influences will pose further challenges in the future, the resilience enhancement of WDS, i.e. the enhancement of their capability to withstand and recover from disturbances, has been in particular focus recently. To assess the resilience of WDS, metrics based on graph theory have been proposed. In this study, a promising approach is applied to assess the resilience of the WDS for a district in a major German City. The conducted analysis provides insight into the process of actively influencing the resilience of WDS}, language = {en} } @inproceedings{Wollert2006, author = {Wollert, J{\"o}rg}, title = {Grundlagen Wireless - Was kann von Funktechnik erwartet werden?}, series = {Wireless technologies : von der Technologie zur Anwendung : 8. Kongress, 27. - 28. September 2006, Dortmund / J{\"o}rg Wollert (Hrsg.) (Fortschritt-Berichte VDI : Reihe 10, Informatik, Kommunikation ; Nr. 772)}, booktitle = {Wireless technologies : von der Technologie zur Anwendung : 8. Kongress, 27. - 28. September 2006, Dortmund / J{\"o}rg Wollert (Hrsg.) (Fortschritt-Berichte VDI : Reihe 10, Informatik, Kommunikation ; Nr. 772)}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, isbn = {3-18-377210-8}, pages = {314 -- 323}, year = {2006}, language = {de} } @inproceedings{Wollert2010, author = {Wollert, J{\"o}rg}, title = {Grundlagen Wireless Technologie}, series = {Wireless Technologies : 12. Kongress, 22. - 23. September 2010, Bochum ; von der Technologie zur Anwendung / J{\"o}rg F. Wollert (Hrsg.) (Fortschritt-Berichte VDI : Reihe 10, Informatik, Kommunikation ; 810)}, booktitle = {Wireless Technologies : 12. Kongress, 22. - 23. September 2010, Bochum ; von der Technologie zur Anwendung / J{\"o}rg F. Wollert (Hrsg.) (Fortschritt-Berichte VDI : Reihe 10, Informatik, Kommunikation ; 810)}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, pages = {322 -- 330}, year = {2010}, language = {de} } @inproceedings{HallmannHeideckerSchlottereretal.2016, author = {Hallmann, Marcus and Heidecker, Ansgar and Schlotterer, Markus and Dachwald, Bernd}, title = {GTOC8: results and methods of team 15 DLR}, series = {26th AAS/AIAA Space Flight Mechanics Meeting, Napa, CA}, booktitle = {26th AAS/AIAA Space Flight Mechanics Meeting, Napa, CA}, year = {2016}, abstract = {This paper describes the results and methods used during the 8th Global Trajectory Optimization Competition (GTOC) of the DLR team. Trajectory optimization is crucial for most of the space missions and usually can be formulated as a global optimization problem. A lot of research has been done to different type of mission problems. The most demanding ones are low thrust transfers with e.g. gravity assist sequences. In that case the optimal control problem is combined with an integer problem. In most of the GTOCs we apply a filtering of the problem based on domain knowledge.}, language = {en} }