@article{OrzadaFiedlerBitzetal.2020,
  author    = {Orzada, Stephan and Fiedler, Thomas M. and Bitz, Andreas and Ladd, Mark E. and Quick, Harald H.},
  title     = {Local SAR compression with overestimation control to reduce maximum relative SAR overestimation and improve multi-channel RF array performance},
  series = {Magnetic Resonance Materials in Physics, Biology and Medicine},
  journal   = {Magnetic Resonance Materials in Physics, Biology and Medicine},
  number    = {34 (2021)},
  publisher = {Springer},
  address   = {Heidelberg},
  isbn      = {1352-8661},
  doi       = {10.1007/s10334-020-00890-0},
  pages     = {153 -- 164},
  year      = {2020},
  abstract  = {Objective In local SAR compression algorithms, the overestimation is generally not linearly dependent on actual local SAR. This can lead to large relative overestimation at low actual SAR values, unnecessarily constraining transmit array performance. Method Two strategies are proposed to reduce maximum relative overestimation for a given number of VOPs. The first strategy uses an overestimation matrix that roughly approximates actual local SAR; the second strategy uses a small set of pre-calculated VOPs as the overestimation term for the compression. Result Comparison with a previous method shows that for a given maximum relative overestimation the number of VOPs can be reduced by around 20\% at the cost of a higher absolute overestimation at high actual local SAR values. Conclusion The proposed strategies outperform a previously published strategy and can improve the SAR compression where maximum relative overestimation constrains the performance of parallel transmission.},
  language  = {en}
}
@article{SchifferFerreinLakemeyer2012,
  author    = {Schiffer, Stefan and Ferrein, Alexander and Lakemeyer, Gerhard},
  title     = {Caesar: an intelligent domestic service robot},
  series = {Intelligent service robotics},
  volume    = {5},
  journal   = {Intelligent service robotics},
  number    = {4},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1861-2776},
  doi       = {10.1007/s11370-012-0118-y},
  pages     = {259 -- 276},
  year      = {2012},
  abstract  = {In this paper we present CAESAR, an intelligent domestic service robot. In domestic settings for service robots complex tasks have to be accomplished. Those tasks benefit from deliberation, from robust action execution and from flexible methods for human-robot interaction that account for qualitative notions used in natural language as well as human fallibility. Our robot CAESAR deploys AI techniques on several levels of its system architecture. On the low-level side, system modules for localization or navigation make, for instance, use of path-planning methods, heuristic search, and Bayesian filters. For face recognition and human-machine interaction, random trees and well-known methods from natural language processing are deployed. For deliberation, we use the robot programming and plan language READYLOG, which was developed for the high-level control of agents and robots; it allows combining programming the behaviour using planning to find a course of action. READYLOG is a variant of the robot programming language Golog. We extended READYLOG to be able to cope with qualitative notions of space frequently used by humans, such as "near" and "far". This facilitates human-robot interaction by bridging the gap between human natural language and the numerical values needed by the robot. Further, we use READYLOG to increase the flexible interpretation of human commands with decision-theoretic planning. We give an overview of the different methods deployed in CAESAR and show the applicability of a system equipped with these AI techniques in domestic service robotics},
  language  = {en}
}
@article{SchaeferHoefkenSchuba2011,
  author    = {Schaefer, Thomas and H{\"o}fken, Hans-Wilhelm and Schuba, Marko},
  title     = {Windows Phone 7 from a Digital Forensics' Perspective},
  publisher = {Springer},
  address   = {Berlin},
  year      = {2011},
  language  = {en}
}
@article{BergmannGoettenBraunetal.2022,
  author    = {Bergmann, Ole and G{\"o}tten, Falk and Braun, Carsten and Janser, Frank},
  title     = {Comparison and evaluation of blade element methods against RANS simulations and test data},
  series = {CEAS Aeronautical Journal},
  volume    = {13},
  journal   = {CEAS Aeronautical Journal},
  publisher = {Springer},
  address   = {Wien},
  issn      = {1869-5590 (Online)},
  doi       = {10.1007/s13272-022-00579-1},
  pages     = {535 -- 557},
  year      = {2022},
  abstract  = {This paper compares several blade element theory (BET) method-based propeller simulation tools, including an evaluation against static propeller ground tests and high-fidelity Reynolds-Average Navier Stokes (RANS) simulations. Two proprietary propeller geometries for paraglider applications are analysed in static and flight conditions. The RANS simulations are validated with the static test data and used as a reference for comparing the BET in flight conditions. The comparison includes the analysis of varying 2D aerodynamic airfoil parameters and different induced velocity calculation methods. The evaluation of the BET propeller simulation tools shows the strength of the BET tools compared to RANS simulations. The RANS simulations underpredict static experimental data within 10\% relative error, while appropriate BET tools overpredict the RANS results by 15-20\% relative error. A variation in 2D aerodynamic data depicts the need for highly accurate 2D data for accurate BET results. The nonlinear BET coupled with XFOIL for the 2D aerodynamic data matches best with RANS in static operation and flight conditions. The novel BET tool PropCODE combines both approaches and offers further correction models for highly accurate static and flight condition results.},
  language  = {en}
}
@article{Ferrein2010,
  author    = {Ferrein, Alexander},
  title     = {Robot controllers for highly dynamic environments with real-time constraints},
  series = {K{\"u}nstliche Intelligenz : KI},
  volume    = {24},
  journal   = {K{\"u}nstliche Intelligenz : KI},
  number    = {2},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {1610-1987},
  doi       = {10.1007/s13218-010-0041-3},
  pages     = {175 -- 178},
  year      = {2010},
  abstract  = {In this extended abstract we describe the robot programming and planning language READYLOG, a GOLOG dialect which was developed to support the decision making of robots acting in dynamic real-time domains like robotic soccer. The formal framework of READYLOG, which is based on the situation calculus, features imperative control structures like loops and procedures, allows for decision-theoretic planning, and accounts for a continuously changing world. We developed high-level controllers in READYLOG for our soccer robots in RoboCup's Middle-size league, but also for service robots and for autonomous agents in interactive computer games.},
  language  = {en}
}
@article{RensVarzinczakMeyeretal.2010,
  author    = {Rens, Gavin and Varzinczak, Ivan and Meyer, Thomas and Ferrein, Alexander},
  title     = {A Logic for Reasoning about Actions and Explicit Observations},
  series = {AI 2010: Advances in Artificial Intelligence 23rd Australasian Joint Conference, Adelaide, Australia, December 7-10, 2010. Proceedings},
  journal   = {AI 2010: Advances in Artificial Intelligence 23rd Australasian Joint Conference, Adelaide, Australia, December 7-10, 2010. Proceedings},
  publisher = {Springer},
  address   = {Berlin},
  doi       = {10.1007/978-3-642-17432-2_40},
  pages     = {395 -- 404},
  year      = {2010},
  language  = {en}
}
@article{MoehrenBergmannJanseretal.2024,
  author    = {M{\"o}hren, Felix and Bergmann, Ole and Janser, Frank and Braun, Carsten},
  title     = {Assessment of structural mechanical effects related to torsional deformations of propellers},
  series = {CEAS Aeronautical Journal},
  journal   = {CEAS Aeronautical Journal},
  publisher = {Springer},
  address   = {Wien},
  issn      = {1869-5590 (eISSN)},
  doi       = {10.1007/s13272-024-00737-7},
  pages     = {22 Seiten},
  year      = {2024},
  abstract  = {Lifting propellers are of increasing interest for Advanced Air Mobility. All propellers and rotors are initially twisted beams, showing significant extension-twist coupling and centrifugal twisting. Torsional deformations severely impact aerodynamic performance. This paper presents a novel approach to assess different reasons for torsional deformations. A reduced-order model runs large parameter sweeps with algebraic formulations and numerical solution procedures. Generic beams represent three different propeller types for General Aviation, Commercial Aviation, and Advanced Air Mobility. Simulations include solid and hollow cross-sections made of aluminum, steel, and carbon fiber-reinforced polymer. The investigation shows that centrifugal twisting moments depend on both the elastic and initial twist. The determination of the centrifugal twisting moment solely based on the initial twist suffers from errors exceeding 5\% in some cases. The nonlinear parts of the torsional rigidity do not significantly impact the overall torsional rigidity for the investigated propeller types. The extension-twist coupling related to the initial and elastic twist in combination with tension forces significantly impacts the net cross-sectional torsional loads. While the increase in torsional stiffness due to initial twist contributes to the overall stiffness for General and Commercial Aviation propellers, its contribution to the lift propeller's stiffness is limited. The paper closes with the presentation of approximations for each effect identified as significant. Numerical evaluations are necessary to determine each effect for inhomogeneous cross-sections made of anisotropic material.},
  language  = {en}
}
@article{BelavyAlbrachtBrueggemannetal.2016,
  author    = {Belavy, Daniel L. and Albracht, Kirsten and Br{\"u}ggemann, Gert-Peter and Vergroesen, Pieter-Paul A. and Dieen, Jaap H. van},
  title     = {Can exercise positively influence the intervertebral disc?},
  series = {Sports Medicine},
  volume    = {46},
  journal   = {Sports Medicine},
  number    = {4},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1179-2035},
  doi       = {10.1007/s40279-015-0444-2},
  pages     = {473 -- 485},
  year      = {2016},
  abstract  = {To better understand what kinds of sports and exercise could be beneficial for the intervertebral disc (IVD), we performed a review to synthesise the literature on IVD adaptation with loading and exercise. The state of the literature did not permit a systematic review; therefore, we performed a narrative review. The majority of the available data come from cell or whole-disc loading models and animal exercise models. However, some studies have examined the impact of specific sports on IVD degeneration in humans and acute exercise on disc size. Based on the data available in the literature, loading types that are likely beneficial to the IVD are dynamic, axial, at slow to moderate movement speeds, and of a magnitude experienced in walking and jogging. Static loading, torsional loading, flexion with compression, rapid loading, high-impact loading and explosive tasks are likely detrimental for the IVD. Reduced physical activity and disuse appear to be detrimental for the IVD. We also consider the impact of genetics and the likelihood of a 'critical period' for the effect of exercise in IVD development. The current review summarises the literature to increase awareness amongst exercise, rehabilitation and ergonomic professionals regarding IVD health and provides recommendations on future directions in research.},
  language  = {en}
}
@article{NiemuellerFerreinLakemeyer2010,
  author    = {Niem{\"u}ller, Tim and Ferrein, Alexander and Lakemeyer, Gerhard},
  title     = {A Lua-based behavior engine for controlling the humanoid robot Nao},
  series = {RoboCup 2009: Robot Soccer World Cup XIII},
  journal   = {RoboCup 2009: Robot Soccer World Cup XIII},
  publisher = {Springer},
  address   = {Heidelberg},
  doi       = {10.1007/978-3-642-11876-0_21},
  pages     = {240 -- 251},
  year      = {2010},
  language  = {en}
}
@article{SchollSchubertZieneretal.2010,
  author    = {Scholl, Ingrid and Schubert, Nicole and Ziener, Pascal and Pietrzyk, Uwe},
  title     = {GPU-basiertes Volumenrendering von multimodalen medizinischen Bilddaten in Echtzeit},
  series = {Bildverarbeitung f{\"u}r die Medizin 2010},
  journal   = {Bildverarbeitung f{\"u}r die Medizin 2010},
  publisher = {Springer},
  address   = {Berlin},
  isbn      = {978-3-642-11967-5},
  pages     = {400 -- 404},
  year      = {2010},
  abstract  = {Die vorliegende Arbeit zeichnet sich dadurch aus, dass registrierte unsegmentierte Volumina aus multimodalen Bilddatens{\"a}tzen (z.B. MRT, PET) gleichzeitig in einer 3D-Rekonstruktion visualisiert werden und in Echtzeit manipuliert werden k{\"o}nnen. Erm{\"o}glicht wird die Echtzeitf{\"a}higkeit durch die Programmierung der Algorithmen zur direkten Volumenvisualisierung auf der Grafikkarte mittels der neuen CUDA-Technologie. Die Zuordnung der Farbeigenschaften wird {\"u}ber 1D-Transferfunktionen f{\"u}r jedes Volumen getrennt gesteuert. So k{\"o}nnen durch die interaktive Ver{\"a}nderung der 1D-Transferfunktion Detailinformationen aus den zwei Bilddatens{\"a}tzen getrennt kontrolliert werden und die Vorteile der verschiedenen Bildmodalit{\"a}ten in einer Visualisierung genutzt werden. Mittels dieses interaktiven Frameworks k{\"o}nnen neue Erkenntnisse insbesondere {\"u}ber neurodegenerativen Erkrankungen gewonnen werden.},
  language  = {de}
}