TY - JOUR A1 - Vorst, Phillip A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard T1 - AllemaniACs3D team description Y1 - 2006 SP - 1 EP - 6 ER - TY - CHAP A1 - Dylla, Frank A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard T1 - AllemaniACs 2003 team description T2 - RoboCup 2003 : Robot Soccer World Cup VII Y1 - 2003 SP - 1 EP - 3 ER - TY - CHAP A1 - Altherr, Lena A1 - Ederer, Thorsten A1 - Vergé, Angela A1 - Pelz, Peter F. T1 - Algorithmische Struktursynthese eines hydrostatischen Getriebes T2 - Antriebssysteme 2015 : Elektrik, Mechanik, Fluidtechnik in der Anwendung Y1 - 2015 SN - 978-3-18-092268-3 N1 - Antriebssysteme 2015 - Elektrik, Mechanik, Fluidtechnik in der Anwendung. VDI/VDE-Fachtagung. 11.11.15-12.11.15, Aachen. Veröffentlicht in der Reihe VDI-Berichte, Bandnummer 2268. SP - 145 EP - 155 PB - VDI-Verlag CY - Düsseldorf ER - TY - CHAP A1 - Altherr, Lena A1 - Ederer, Thorsten A1 - Schänzle, Christian A1 - Lorenz, Ulf A1 - Pelz, Peter F. T1 - Algorithmic system design using scaling and affinity laws T2 - Operations Research Proceedings 2015 N2 - Energy-efficient components do not automatically lead to energy-efficient systems. Technical Operations Research (TOR) shifts the focus from the single component to the system as a whole and finds its optimal topology and operating strategy simultaneously. In previous works, we provided a preselected construction kit of suitable components for the algorithm. This approach may give rise to a combinatorial explosion if the preselection cannot be cut down to a reasonable number by human intuition. To reduce the number of discrete decisions, we integrate laws derived from similarity theory into the optimization model. Since the physical characteristics of a production series are similar, it can be described by affinity and scaling laws. Making use of these laws, our construction kit can be modeled more efficiently: Instead of a preselection of components, it now encompasses whole model ranges. This allows us to significantly increase the number of possible set-ups in our model. In this paper, we present how to embed this new formulation into a mixed-integer program and assess the run time via benchmarks. We present our approach on the example of a ventilation system design problem. KW - Optimal Topology KW - Piecewise Linearization KW - Ventilation System KW - Similarity Theory Y1 - 2017 SN - 978-3-319-42901-4 SN - 978-3-319-42902-1 U6 - https://doi.org/10.1007/978-3-319-42902-1 N1 - International Conference of the German, Austrian and Swiss Operations Research Societies (GOR, ÖGOR, SVOR/ASRO), University of Vienna, Austria, September 1-4, 2015 SP - 605 EP - 611 PB - Springer CY - Cham ER - TY - BOOK A1 - Altherr, Lena T1 - Algorithmic System Design under Consideration of Dynamic Processes N2 - Nach Stand von Wissenschaft und Technik werden Komponenten hinsichtlich ihrer Eigenschaften, wie Lebensdauer oder Energieeffizienz, optimiert. Allerdings können selbst hervorragende Komponenten zu ineffizienten oder instabilen Systemen führen, wenn ihr Zusammenspiel nur unzureichend berücksichtigt wird. Eine Systembetrachtung schafft ein größeres Optimierungspotential - dem erhöhten Potential steht jedoch auch ein erhöhter Komplexitätsgrad gegenüber. Die vorliegende Arbeit ist im Rahmen des Sonderforschungsbereichs 805 entstanden, dessen Ziel die Beherrschung von Unsicherheit in Systemen des Maschinenbaus ist. Die Arbeit zeigt anhand eines realen Systems aus dem Bereich der Hydraulik, wie Unsicherheit in der Entwicklungsphase beherrscht werden kann. Hierbei ist neu, dass die durch den späteren Betrieb zu erwartende Systemdegradation eines jeden möglichen Systemvorschlags antizipiert werden kann. Dadurch können Betriebs- und Wartungskosten vorausgesagt und minimiert werden und durch eine optimale Betriebs- und Wartungsstrategie die Verfügbarkeit des Systems garantiert werden. Wesentliche Fragen bei der optimalen Auslegung des betrachteten hydrostatischen Getriebes sind dessen physikalische Modellierung, die Darstellung des Optimierungsproblems als gemischt-ganzzahliges lineares Programm, und dessen algorithmische Behandlung zur Lösungsfindung. Hierzu werden Heuristiken zum schnelleren Auffinden sinnvoller Systemtopologien vorgestellt und mittels mathematischer Dekomposition eine Bewertung des dynamischen Verschleiß- und Wartungsverlaufs möglicher Systemvorschläge vorgenommen. Die Arbeit stellt die Optimierung technischer Systeme an der Schnittstelle von Mathematik, Informatik und Ingenieurwesen sowohl gründlich als auch anschaulich und nachvollziehbar dar. KW - Mixed Integer Programming KW - Technical Operations Research KW - Optimization KW - System Design Y1 - 2016 SN - 978-3-8440-4848-3 PB - Shaker CY - Aachen ER - TY - JOUR A1 - Altherr, Lena A1 - Leise, Philipp A1 - Pfetsch, Marc E. A1 - Schmitt, Andreas T1 - Algorithmic design and resilience assessment of energy efficient high-rise water supply systems JF - Applied Mechanics and Materials N2 - High-rise water supply systems provide water flow and suitable pressure in all levels of tall buildings. To design such state-of-the-art systems, the consideration of energy efficiency and the anticipation of component failures are mandatory. In this paper, we use Mixed-Integer Nonlinear Programming to compute an optimal placement of pipes and pumps, as well as an optimal control strategy.Moreover, we consider the resilience of the system to pump failures. A resilient system is able to fulfill a predefined minimum functionality even though components fail or are restricted in their normal usage. We present models to measure and optimize the resilience. To demonstrate our approach, we design and analyze an optimal resilient decentralized water supply system inspired by a real-life hotel building. KW - MINLP KW - Buffering Capacity KW - Uncertainty KW - Water Supply Networks KW - Booster Stations Y1 - 2018 U6 - https://doi.org/10.4028/www.scientific.net/AMM.885.211 SN - 1662-7482 VL - 885 SP - 211 EP - 223 PB - Trans Tech Publications CY - Bäch ER - TY - BOOK A1 - Hagemann, Hans-Jürgen T1 - Akzeptorionen in BaTiO3 und SrTiO3 und ihre Auswirkungen auf die Eigenschaften von Titanatkeramiken Y1 - 1980 N1 - Aachen, Techn.Hochsch., Fak.f.Elektrotechnik, Diss. ER - TY - JOUR A1 - Gligorevic, Snjezana T1 - Airport surface propagation channel in the C-Band: measurements and modeling JF - IEEE transactions on antennas and propagation Y1 - 2013 SN - 0018-926x VL - Vol. 61 IS - Iss. 9 SP - 4792 EP - 4802 PB - IEEE CY - New York ER - TY - CHAP A1 - Gligorevic, Snjezana A1 - Zierhut, R. A1 - Jost, T. A1 - Wang, Wei T1 - Airport channel measurements at 5.2GHz T2 - 3rd European Conference on Antennas and Propagation : (EuCAP) ; Berlin, Germany, 23 - 27 March 2009 Y1 - 2009 SN - 978-1-4244-4753-4 ; 978-3-00-024573-2 SP - 877 EP - 881 ER - TY - CHAP A1 - Marco, Heather G. A1 - Ferrein, Alexander T1 - AGNES: The African-German Network of Excellence in Science T2 - Proceedings of the 2nd Developing World Robotics Forum, Workshop at IEEE AFRICON 2017 Y1 - 2017 SP - 1 EP - 2 ER - TY - JOUR A1 - Hartung, Frank A1 - Niebert, Norbert A1 - Schieder, Andreas A1 - Rembarz, René T1 - Advances in network-supported media delivery in next-generation mobile systems / Hartung, Frank ; Niebert, Norbert ; Schieder, Andreas ; Rembarz, René ; Schmid, Stefan ; Eggert, Lars JF - IEEE Communications Magazine. 44 (2006), H. 8 Y1 - 2006 SN - 0163-6804 SP - 82 EP - 89 ER - TY - JOUR A1 - Deserno, Thomas M. A1 - Aach, Til A1 - Amunts, Katrin A1 - Hillen, Walter A1 - Kuhlen, Torsten A1 - Scholl, Ingrid T1 - Advances in medical image processing : A special Issue on the Workshop in Aachen, Germany, March 2010 JF - Computer Science - Research and Development. 26 (2011), H. 1-2 Y1 - 2011 SN - 1865-2042 SP - 1 EP - 3 PB - springer CY - Berlin ER - TY - JOUR A1 - Heuermann, Holger A1 - Rumiantsev, A. A1 - Schott, S. T1 - Advanced on-wafer multiport calibration methods for mono- and mixed-mode device characterization JF - On wafer characterization : 63rd ARFTG conference digest, spring 2004, 11 June 2004, Fort Worth, TX / Automatic RF Techniques Group. [Conference chair: John Cable. Publication chair: J. G. Burns] Y1 - 2004 SN - 0-7803-8371-0 N1 - Microwave Theory and Techniques Society. ; Automatic RF Techniques Group ; ARFTG conference ; (63 : ; 2004.06.11 : ; Fort Worth, Tex.) SP - 91 EP - 96 PB - IEEE Operations Center CY - Piscataway, NJ ER - TY - CHAP A1 - Gebhardt, Andreas A1 - Ritz, Thomas A1 - Siekmann, Kirsten A1 - Wallenborn, Ramona ED - Demmer, Axel T1 - Additive manufacturing businesses in the process chain of individualized mass products T2 - DDMC 2014 : Proceedings of the Fraunhofer Direct Digital Manufacturing Conference Y1 - 2014 SN - 978-3-8396-9128-1 (E-Book) PB - Fraunhofer CY - Stuttgart ER - TY - CHAP A1 - Damm, Sebastian A1 - Ritz, Thomas A1 - Strauch, Jakob T1 - Adaption of archetype patterns for mobile cloud-based business apps T2 - 2011 IEEE International Conference on Pervasive Computing and Communications workshops (PerCom workshops 2011) : Seattle, Washington, USA, 21 - 25 March 2011 Y1 - 2011 SN - 978-1-61284-938-6 (Print) SN - 978-1-61284-936-2 (E-Book) U6 - https://doi.org/10.1109/PERCOMW.2011.5766849 SP - 100 EP - 105 PB - IEEE Service Center CY - Piscataway, NJ ER - TY - JOUR A1 - Ritz, Thomas A1 - Stender, Michael ED - Weisbecker, Anette T1 - Ad-hoc Anwendungsintegration mit mobilen CRM-Systement JF - Electronic Business : Innovationen, Anwendungen und Technologien Y1 - 2004 SN - 3-8167-6621-8 SP - 92 EP - 97 PB - Fraunhofer-IRB-Verl. CY - Stuttgart ER - TY - JOUR A1 - Ferrein, Alexander A1 - Steinbauer, Gerald A1 - Vassos, Stavros T1 - Action-Based Imperative Programming with YAGI N2 - Many tasks for autonomous agents or robots are best described by a specification of the environment and a specification of the available actions the agent or robot can perform. Combining such a specification with the possibility to imperatively program a robot or agent is what we call the actionbased imperative programming. One of the most successful such approaches is Golog. In this paper, we draft a proposal for a new robot programming language YAGI, which is based on the action-based imperative programming paradigm. Our goal is to design a small, portable stand-alone YAGI interpreter. We combine the benefits of a principled domain specification with a clean, small and simple programming language, which does not exploit any side-effects from the implementation language. We discuss general requirements of action-based programming languages and outline YAGI, our action-based language approach which particularly aims at embeddability. Y1 - 2012 N1 - Cognitive Robotics AAAI Technical Report WS-12-06 SP - 24 EP - 31 ER - TY - JOUR A1 - Ferrein, Alexander A1 - Dylla, Frank A1 - Lakemeyer, Gerhard T1 - Acting and Deliberating using Golog in Robotic Soccer - A Hybrid Architecture / Dylla, Frank ; Ferrein, Alexander ; Lakemeyer, Gerhard JF - Proc. 3rd International Cognitive Robotics Workshop (CogRob 2002) Y1 - 2002 SP - 1 EP - 7 ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Niendorf, Thoralf A1 - Kob, Malte T1 - Acoustic method for synchronization of Magnetic Resonance Imaging (MRI) JF - Acta Acustica N2 - Magnetic Resonance Imaging (MRI) of moving organs requires synchronization with physiological motion or flow, which dictate the viable window for data acquisition. To meet this challenge, this study proposes an acoustic gating device (ACG) that employs acquisition and processing of acoustic signals for synchronization while providing MRI compatibility, immunity to interferences with electro-magnetic and acoustic fields and suitability for MRI at high magnetic field strengths. The applicability and robustness of the acoustic gating approach is examined in a pilot study, where it substitutes conventional ECG-gating for cardiovascular MR. The merits and limitations of the ACG approach are discussed. Implications for MR imaging in the presence of physiological motion are considered including synchronization with other structure- or motion borne sounds. Y1 - 2008 U6 - https://doi.org/10.3813/AAA.918017 SN - 1861-9959 VL - 94 IS - 1 SP - 148 EP - 155 PB - Hirzel CY - Stuttgart ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Hezel, Fabian A1 - Renz, Wolfgang A1 - de Geyer d'Orth, Thibaut A1 - Dieringer, Matthias A1 - von Knobelsdorf-Brenkenhoff, Florian A1 - Prothmann, Marcel A1 - Schulz-Menger, Jeanette A1 - Niendorf, Thoralf T1 - Acoustic cardiac triggering: a practical solution for synchronization and gating of cardiovascular magnetic resonance at 7 Tesla JF - Journal of Cardiovascular Magnetic Resonance N2 - Background To demonstrate the applicability of acoustic cardiac triggering (ACT) for imaging of the heart at ultrahigh magnetic fields (7.0 T) by comparing phonocardiogram, conventional vector electrocardiogram (ECG) and traditional pulse oximetry (POX) triggered 2D CINE acquisitions together with (i) a qualitative image quality analysis, (ii) an assessment of the left ventricular function parameter and (iii) an examination of trigger reliability and trigger detection variance derived from the signal waveforms. Results ECG was susceptible to severe distortions at 7.0 T. POX and ACT provided waveforms free of interferences from electromagnetic fields or from magneto-hydrodynamic effects. Frequent R-wave mis-registration occurred in ECG-triggered acquisitions with a failure rate of up to 30% resulting in cardiac motion induced artifacts. ACT and POX triggering produced images free of cardiac motion artefacts. ECG showed a severe jitter in the R-wave detection. POX also showed a trigger jitter of approximately Δt = 72 ms which is equivalent to two cardiac phases. ACT showed a jitter of approximately Δt = 5 ms only. ECG waveforms revealed a standard deviation for the cardiac trigger offset larger than that observed for ACT or POX waveforms. Image quality assessment showed that ACT substantially improved image quality as compared to ECG (image quality score at end-diastole: ECG = 1.7 ± 0.5, ACT = 2.4 ± 0.5, p = 0.04) while the comparison between ECG vs. POX gated acquisitions showed no significant differences in image quality (image quality score: ECG = 1.7 ± 0.5, POX = 2.0 ± 0.5, p = 0.34). Conclusions The applicability of acoustic triggering for cardiac CINE imaging at 7.0 T was demonstrated. ACT's trigger reliability and fidelity are superior to that of ECG and POX. ACT promises to be beneficial for cardiovascular magnetic resonance at ultra-high field strengths including 7.0 T. KW - Interval Time Series KW - Image Quality Score KW - Image Quality Assessment KW - Sound Pressure Level KW - Cardiovascular Magnetic Resonance Y1 - 2010 U6 - https://doi.org/10.1186/1532-429X-12-67 SN - 1532-429X VL - 12 IS - 1 PB - Elsevier CY - Amsterdam ER -