TY - JOUR A1 - Prume, Klaus A1 - Zalachas, Nicolas A1 - Laskewitz, Bernd A1 - Kamlah, Marc T1 - Effective Piezoelectric Coefficients of Ferroelectric Thin Films on Elastic Substrates / Zalachas, Nicolas ; Laskewitz, Bernd ; Kamlah, Marc ; Prume, Klaus ; Lapusta, Yuri ; Tiedke, Stephan JF - Journal of Intelligent Material Systems and Structures. 20 (2008), H. 6 Y1 - 2008 SN - 1045-389X SP - 683 EP - 695 ER - TY - JOUR A1 - Prume, Klaus A1 - Waser, Rainer A1 - Franken, Klaus A1 - Maier, Horst R. T1 - Finite-Element Analysis of Ceramic Multilayer Capacitors: Modeling and Electrical Impedance Spectroscopy for a Nondestructive Failure Test / Prume, Klaus ; Waser, Rainer ; Franken, Klaus ; Maier, Horst R. ; JF - Journal of the American Ceramic Society. 83 (2000), H. 5 Y1 - 2000 SN - 0002-7820 SP - 1153 EP - 1159 ER - TY - JOUR A1 - Prume, Klaus A1 - Waser, Rainer T1 - Finite-element simulation of coupled characteristics of ceramic multilayer capacitors under transient electrical loading / Prume, Klaus ; Waser, Rainer JF - Proceedings of the 2000 12th IEEE International Symposium on Applications of Ferroelectrics. Vol. 2 Y1 - 2000 N1 - ISAF 2000. Proceedings of the 2000 12th IEEE International Symposium on Applications of Ferroelectrics SP - 675 EP - 678 ER - TY - JOUR A1 - Prume, Klaus A1 - Tyholdt, F. A1 - Calame, F. A1 - Raeder, H. T1 - Chemically derived seeding layer for {100}-textured PZT thin films / Tyholdt, F. ; Calame, F. ; Prume, K. ; Raeder, H. ; Muralt, P. JF - Journal of Electroceramics. 19 (2007), H. 4 Y1 - 2007 SN - 1385-3449 SP - 311 EP - 314 ER - TY - JOUR A1 - Prume, Klaus A1 - Tiedke, S. A1 - Schmitz, T. A1 - Roelofs, A. T1 - Direct hysteresis measurements of single nanosized ferroelectric capacitors contacted with an atomic force microscope / Tiedke, S. ; Schmitz, T. ; Prume, K. ; Roelofs, A. ; Schneller, T. ; Kall, U. ; Waser, R. ; Ganpule, C. S. ; Nagarajan, V. ; Stanishevs JF - Applied Physics Letters. 79 (2001), H. 22 Y1 - 2001 SN - 0003-6951 SP - 3678 EP - 3680 ER - TY - JOUR A1 - Prume, Klaus A1 - Roelofs, Andreas A1 - Schmitz, Thorsten A1 - Reichenberg, Bernd T1 - Compensation of the Parasitic Capacitance of a Scanning Force Microscope Cantilever Used for Measurements on Ferroelectric Capacitors of Submicron Size by Means of Finite Element Simulations / Prume, Klaus ; Roelofs, Andreas ; Schmitz, Thorsten ; Reichenb JF - Japanese Journal of Applied Physics. 41 (2002), H. 11B Y1 - 2002 SN - 0021-4922 SP - 7198 EP - 7201 ER - TY - JOUR A1 - Prume, Klaus A1 - Reichenberg, B. A1 - Roelofs, A. A1 - Waser, R. T1 - In-situ compensation of the parasitic capacitance for nanoscale hysteresis measurements / Schmitz, T. ; Prume, K. ; Reichenberg, B. ; Roelofs, A. ; Waser, R. ; Tiedke, S. JF - Journal of the European Ceramic Society. 24 (2004), H. 6 Y1 - 2004 SN - 0955-2219 N1 - Electroceramics VIII SP - 1145 EP - 1147 ER - TY - JOUR A1 - Prume, Klaus A1 - Raeder, H. A1 - Tyholdt, F. A1 - Booij, W. E. T1 - Taking piezoelectric microsystems from the laboratory to production / Raeder, H. ; Tyholdt, F. ; Booij, W. ; Calame, F. ; Ostbo, N. P. ; Bredesen, R. ; Prume, K. ; Rijnders, G. ; Muralt, P. JF - Journal of Electroceramics. 19 (2007), H. 4 Y1 - 2007 SN - 1385-3449 SP - 357 EP - 362 ER - TY - JOUR A1 - Prume, Klaus A1 - Peter, F. A1 - Rüdiger, A. A1 - Dittmann, R. T1 - Analysis of shape effects on the piezoresponse in ferroelectric nanograins with and without adsorbates / Peter, F. ; Rüdiger, A. ; Dittmann, R. ; Waser, R. ; Szot, K. ; Reichenberg, B. ; Prume, K. ; JF - Applied Physics Letters . 87 (2005), H. 8 Y1 - 2005 SN - 0003-6951 SP - 082901 EP - 082901-3 ER - TY - JOUR A1 - Prume, Klaus A1 - Muralt, Paul A1 - Calame, Florian A1 - Schmitz-Kempen, Thorsten T1 - Extensive electromechanical characterization of PZT thin films for MEMS applications by electrical and mechanical excitation signals / Prume, Klaus ; Muralt, Paul ; Calame, Florian ; Schmitz-Kempen, Thorsten ; Tiedke, Stephan JF - Journal of Electroceramics. 19 (2007), H. 4 Y1 - 2007 SN - 1385-3449 SP - 407 EP - 411 ER - TY - JOUR A1 - Prume, Klaus A1 - Muralt, P. A1 - Calame, F. A1 - Schmitz-Kempen, T. T1 - Piezoelectric thin films: evaluation of electrical and electromechanical characteristics for MEMS devices / Prume, K. ; Muralt, P. ; Calame, F. ; Schmitz-Kempen, T. ; Tiedke, S. ; JF - IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control. 54 (2007), H. 1 Y1 - 2007 SN - 0885-3010 SP - 81 EP - 14 ER - TY - JOUR A1 - Prume, Klaus A1 - Meyer, René A1 - Waser, Rainer A1 - Schmitz, Torsten T1 - Dynamic leakage current compensation in ferroelectric thin-film capacitor structures / Meyer, René ; Waser, Rainer ; Prume, Klaus ; Schmitz, Torsten ; Tiedke, Stephan JF - Applied Physics Letters . 86 (2005), H. 14 Y1 - 2005 SN - 0003-6951 SP - 142907-1 EP - 142907-3 ER - TY - JOUR A1 - Prume, Klaus A1 - Gerber, Peter A1 - Kügeler, Carsten A1 - Roelofs, Andreas T1 - Simulation and measurements of the piezoelectric properties response (d33) of piezoelectric layered thin film structures influenced by the top-electrode size / Prume, K. ; Gerber, P. ; Kügeler, C. ; Roelofs, A. ; Böttger, U. ; Waser, R. ; Schmitz-Kempen, Y1 - 2004 SN - 0-7803-8410-5 N1 - 14th IEEE International Symposium on Applications of Ferroelectrics, 2004. ISAF-04. 2004 SP - 7 EP - 10 ER - TY - JOUR A1 - Prume, Klaus A1 - Gerber, P. A1 - Roelofs, A. A1 - Kügeler, C. T1 - Effects of the top-electrode size on the piezoelectric properties (d33 and S) of lead zirconate titanate thin films / Gerber, P. ; Roelofs, A. ; Kügeler, C.; Böttger, U. ; Waser, R. ; Prume, K. ; JF - Journal of Applied Physics . 96 (2004), H. 5 Y1 - 2004 SN - 0021-8979 SP - 2800 EP - 2804 ER - TY - JOUR A1 - Prume, Klaus A1 - Franken, Klaus A1 - Maier, Horst R. A1 - Waser, Rainer T1 - Finite-Element Analysis of Ceramic Multilayer Capacitors: Failure Probability Caused by Wave Soldering and Bending Loads / Franken, Klaus ; Maier, Horst R. ; Prume, Klaus ; Waser, Rainer JF - Journal of the American Ceramic Society. 83 (2000), H. 6 Y1 - 2000 SN - 0002-7820 SP - 1433 EP - 1440 ER - TY - JOUR A1 - Prume, Klaus A1 - Franken, Klaus A1 - Böttger, Ulrich A1 - Waser, Rainer T1 - Modelling and numerical simulation of the electrical, mechanical, and thermal coupled behaviour of Multilayer capacitors (MLCs) / Prume, Klaus ; Franken, Klaus ; Böttger, Ulrich ; Waser, Rainer ; Maier, Horst R. JF - Journal of the European Ceramic Society. 22 (2002), H. 8 Y1 - 2002 SN - 0955-2219 SP - 1285 EP - 1296 ER - TY - JOUR A1 - Prume, Klaus A1 - Booij, W. E. A1 - Vogl, A. H. A1 - Wang, D. T. T1 - A simple and powerful analytical model for MEMS piezoelectric multimorphs / Booij, W. E. ; Vogl, A. H. ; Wang, D. T. ; Tyholdt, F. ; Ostbo, N. P. ; Raeder, H. ; Prume, K. JF - Journal of Electroceramics. 19 (2007), H. 4 Y1 - 2007 SN - 1385-3449 SP - 387 EP - 393 ER - TY - JOUR A1 - Prume, Klaus T1 - Electrical and electromechanical characterization of piezoelectric thin films in view of MEMS application / Tiedke, S. ; Prume, K. ; Schmitz-Kempen, T.; Y1 - 2007 N1 - ISAF 2007. Sixteenth IEEE International Symposium on Applications of Ferroelectrics, 2007 SP - 702 ER - TY - JOUR A1 - Prochnow, Nora A1 - Gebing, Tina A1 - Ladage, Kerstin A1 - Krause-Finkeldey, Dorothee A1 - Ourdi, Abessamad El A1 - Bitz, Andreas A1 - Streckert, Joachim A1 - Hansen, Volkert A1 - Dermietzel, Rolf T1 - Electromagnetic field effect or simply stress? Effects of UMTS exposure on hippocampal longterm plasticity in the context of procedure related hormone release JF - PLoS one N2 - Harmful effects of electromagnetic fields (EMF) on cognitive and behavioural features of humans and rodents have been controversially discussed and raised persistent concern about adverse effects of EMF on general brain functions. In the present study we applied radio-frequency (RF) signals of the Universal Mobile Telecommunications System (UMTS) to full brain exposed male Wistar rats in order to elaborate putative influences on stress hormone release (corticosteron; CORT and adrenocorticotropic hormone; ACTH) and on hippocampal derived synaptic long-term plasticity (LTP) and depression (LTD) as electrophysiological hallmarks for memory storage and memory consolidation. Exposure was computer controlled providing blind conditions. Nominal brain-averaged specific absorption rates (SAR) as a measure of applied mass-related dissipated RF power were 0, 2, and 10 W/kg over a period of 120 min. Comparison of cage exposed animals revealed, regardless of EMF exposure, significantly increased CORT and ACTH levels which corresponded with generally decreased field potential slopes and amplitudes in hippocampal LTP and LTD. Animals following SAR exposure of 2 W/kg (averaged over the whole brain of 2.3 g tissue mass) did not differ from the sham-exposed group in LTP and LTD experiments. In contrast, a significant reduction in LTP and LTD was observed at the high power rate of SAR (10 W/kg). The results demonstrate that a rate of 2 W/kg displays no adverse impact on LTP and LTD, while 10 W/kg leads to significant effects on the electrophysiological parameters, which can be clearly distinguished from the stress derived background. Our findings suggest that UMTS exposure with SAR in the range of 2 W/kg is not harmful to critical markers for memory storage and memory consolidation, however, an influence of UMTS at high energy absorption rates (10 W/kg) cannot be excluded. Y1 - 2011 U6 - http://dx.doi.org/10.1371/journal.pone.0019437 VL - 6 IS - 5 PB - PLOS CY - San Francisco ER - TY - JOUR A1 - Oßmann, Martin A1 - Kazay, B. T1 - Simple circuit provides high-side current sensing / Ossmann, M ; Kazay, B. JF - EDN. 45 (2000), H. 21 Y1 - 2000 SN - 0012-7515 SP - 200 EP - 200 ER - TY - JOUR A1 - Oßmann, Martin A1 - Kazay, B. T1 - Single mu C pin makes half-duplex RS-232C / Ossmann, M JF - EDN. 44 (1999), H. 16 Y1 - 1999 SN - 0012-7515 SP - 118 ER - TY - JOUR A1 - Oßmann, Martin A1 - Hattrup, C. A1 - Broeck, H. W. van der T1 - Fast estimation techniques for digital control of resonant converters / Hattrup, C.; van der Broeck, H.W.; Ossmann, M.; JF - IEEE Transaction on Power Electronics. 18 (2003), H. 1 Y1 - 2003 SN - 0885-8993 N1 - Part 2 SP - 365 EP - 372 ER - TY - JOUR A1 - Orzada, Stephan A1 - Solbach, Klaus A1 - Gratz, Marcel A1 - Brunheim, Sascha A1 - Fiedler, Thomas M. A1 - Johst, Sören A1 - Bitz, Andreas A1 - Shooshtary, Samaneh A1 - Abuelhaija, Asjraf A1 - Voelker, Maximilian N. A1 - Rietsch, Stefan H. G. A1 - Kraff, Oliver A1 - Maderwald, Stefan A1 - Flöser, Martina A1 - Oehmingen, Mark A1 - Quick, Harald H. A1 - Ladd, Mark E. T1 - A 32-channel parallel transmit system add-on for 7T MRI JF - Plos one Y1 - 2019 U6 - http://dx.doi.org/10.1371/journal.pone.0222452 ER - TY - JOUR A1 - Orzada, Stephan A1 - Maderwald, Stefan A1 - Poser, Benedikt Andreas A1 - Bitz, Andreas A1 - Quick, Harald H. A1 - Ladd, Mark E. T1 - RF excitation using time interleaved acquisition of modes (TIAMO) to address B1 inhomogeneity in high-field MRI JF - Magnetic Resonance in Medicine N2 - As the field strength and, therefore, the operational frequency in MRI is increased, the wavelength approaches the size of the human head/body, resulting in wave effects, which cause signal decreases and dropouts. Several multichannel approaches have been proposed to try to tackle these problems, including RF shimming, where each element in an array is driven by its own amplifier and modulated with a certain (constant) amplitude and phase relative to the other elements, and Transmit SENSE, where spatially tailored RF pulses are used. In this article, a relatively inexpensive and easy to use imaging scheme for 7 Tesla imaging is proposed to mitigate signal voids due to B1 field inhomogeneity. Two time-interleaved images are acquired using a different excitation mode for each. By forming virtual receive elements, both images are reconstructed together using GRAPPA to achieve a more homogeneous image, with only small SNR and SAR penalty in head and body imaging at 7 Tesla. Y1 - 2010 U6 - http://dx.doi.org/10.1002/mrm.22527 SN - 1522-2594 VL - 64 IS - 2 SP - 327 EP - 333 PB - Wiley-Liss CY - New York ER - TY - JOUR A1 - Orzada, Stephan A1 - Ladd, Mark E. A1 - Bitz, Andreas T1 - A method to approximate maximum local SAR in multichannel transmit MR systems without transmit phase information JF - Magnetic Resonance in Medicine N2 - Purpose To calculate local specific absorption rate (SAR) correctly, both the amplitude and phase of the signal in each transmit channel have to be known. In this work, we propose a method to derive a conservative upper bound for the local SAR, with a reasonable safety margin without knowledge of the transmit phases of the channels. Methods The proposed method uses virtual observation points (VOPs). Correction factors are calculated for each set of VOPs that prevent underestimation of local SAR when the VOPs are applied with the correct amplitudes but fixed phases. Results The proposed method proved to be superior to the worst-case calculation based on the maximum eigenvalue of the VOPs. The mean overestimation for six coil setups could be reduced, whereas no underestimation of the maximum local SAR occurred. In the best investigated case, the overestimation could be reduced from a factor of 3.3 to a factor of 1.7. Conclusion The upper bound for the local SAR calculated with the proposed method allows a fast estimation of the local SAR based on power measurements in the transmit channels and facilitates SAR monitoring in systems that do not have the capability to monitor transmit phases Y1 - 2016 U6 - http://dx.doi.org/10.1002/mrm.26398 SN - 1522-2594 VL - 78 IS - 2 SP - 805 EP - 811 PB - International Society for Magnetic Resonance in Medicine ER - TY - JOUR A1 - Orzada, Stephan A1 - Johst, Sören A1 - Maderwald, Stefan A1 - Bitz, Andreas A1 - Solbach, Klaus A1 - Ladd, Mark E. T1 - Mitigation of B1(+) inhomogeneity on single-channel transmit systems with TIAMO JF - Magnetic Resonance in Medicine Y1 - 2013 U6 - http://dx.doi.org/10.1002/mrm.24453 SN - 1522-2594 VL - 70 IS - 1 SP - 290 EP - 294 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Orzada, Stephan A1 - Fiedler, Thomas M. A1 - Bitz, Andreas A1 - Ladd, Mark E. A1 - Quick, Harald H. T1 - Local SAR compression with overestimation control to reduce maximum relative SAR overestimation and improve multi-channel RF array performance JF - Magnetic Resonance Materials in Physics, Biology and Medicine N2 - 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. Y1 - 2020 SN - 1352-8661 U6 - http://dx.doi.org/10.1007/s10334-020-00890-0 IS - 34 (2021) SP - 153 EP - 164 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Orzada, Stephan A1 - Bitz, Andreas A1 - Schäfer, Lena C. A1 - Ladd, Susanne C. A1 - Ladd, Mark E. A1 - Maderwald, Stefan T1 - Open design eight-channel transmit/receive coil for high-resolution and real-time ankle imaging at 7 T JF - Medical Physics N2 - Purpose: At 1.5 T, real-time MRI of joint movement has been shown to be feasible. However, 7 T, provides higher SNR and thus an improved potential for parallel imaging acceleration. The purpose of this work was to build an open, U-shaped eight-channel transmit/receive microstrip coil for 7 T MRI to enable high-resolution and real-time imaging of the moving ankle joint. Methods: A U-shaped eight-channel transmit/receive array for the human ankle was built.urn:x-wiley:00942405:mp3399:equation:mp3399-math-0001-parameters and urn:x-wiley:00942405:mp3399:equation:mp3399-math-0002-factor were measured. SAR calculations of different ankle postures were performed to ensure patient safety. Inhomogeneities in the transmit field consequent to the open design were compensated for by the use of static RF shimming. High-resolution and real-time imaging was performed in human volunteers. Results: The presented array showed good performance with regard to patient comfort and image quality. High acceleration factors of up to 4 are feasible without visible acceleration artifacts. Reasonable image homogeneity was achieved with RF shimming. Conclusions: Open, noncylindrical designs for transmit/receive coils are practical at 7 T and real-time imaging of the moving joint is feasible with the presented coil design. Y1 - 2011 U6 - http://dx.doi.org/10.1118/1.3553399 SN - 2473-4209 VL - 38 IS - 3 SP - 1162 EP - 1167 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Orzada, Stephan A1 - Bitz, Andreas A1 - Johst, Sören A1 - Gratz, Marcel A1 - Völker, Maximilian N. A1 - Kraff, Oliver A1 - Abuelhaija, Ashraf A1 - Fiedler, Thomas M. A1 - Solbach, Klaus A1 - Quick, Harald H. A1 - Ladd, Mark E. T1 - Analysis of an integrated 8-Channel Tx/Rx body array for use as a body coil in 7-Tesla MRI JF - Frontiers in Physics Y1 - 2017 U6 - http://dx.doi.org/10.3389/fphy.2017.00017 SN - 2296-424X N1 - Article number 17 VL - 5 IS - Jun ER - TY - JOUR A1 - Orzada, S. A1 - Maderwald, S. A1 - Poser, B. A. A1 - Johst, S. A1 - Kannengiesser, S. A1 - Ladd, M. E. A1 - Bitz, Andreas T1 - Time-interleaved acquisition of modes: an analysis of SAR and image contrast implications JF - Magnetic Resonance in Medicine N2 - s the magnetic field strength and therefore the operational frequency in MRI are increased, the radiofrequency wavelength approaches the size of the human head/body, resulting in wave effects which cause signal decreases and dropouts. Especially, whole-body imaging at 7 T and higher is therefore challenging. Recently, an acquisition scheme called time-interleaved acquisition of modes has been proposed to tackle the inhomogeneity problems in high-field MRI. The basic premise is to excite two (or more) different Burn:x-wiley:07403194:media:MRM23081:tex2gif-stack-1 modes using static radiofrequency shimming in an interleaved acquisition, where the complementary radiofrequency patterns of the two modes can be exploited to improve overall signal homogeneity. In this work, the impact of time-interleaved acquisition of mode on image contrast as well as on time-averaged specific absorption rate is addressed in detail. Time-interleaved acquisition of mode is superior in Burn:x-wiley:07403194:media:MRM23081:tex2gif-stack-2 homogeneity compared with conventional radiofrequency shimming while being highly specific absorption rate efficient. Time-interleaved acquisition of modes can enable almost homogeneous high-field imaging throughout the entire field of view in PD, T2, and T2*-weighted imaging and, if a specified homogeneity criterion is met, in T1-weighted imaging as well. Y1 - 2012 U6 - http://dx.doi.org/10.1002/mrm.23081 SN - 1522-2594 VL - 67 IS - 4 SP - 1033 EP - 1041 PB - Wiley-Liss CY - New York ER - TY - JOUR A1 - Noureddine, Yacine A1 - Kraff, Oliver A1 - Ladd, Mark E. A1 - Wrede, Karsten H. A1 - Chen, Bixia A1 - Quick, Harald H. A1 - Schaefers, Gregor A1 - Bitz, Andreas T1 - In vitro and in silico assessment of RF-induced heating around intracranial aneurysm clips at 7 Tesla JF - Magnetic Resonance in Medicine Y1 - 2017 U6 - http://dx.doi.org/10.1002/mrm.26650 SN - 1522-2594 IS - Early view PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Noureddine, Yacine A1 - Kraff, Oliver A1 - Ladd, Mark E. A1 - Wrede, Karsten A1 - Chen, Bixia A1 - Quick, Harald H. A1 - Schaefers, Georg A1 - Bitz, Andreas T1 - Radiofrequency induced heating around aneurysm clips using a generic birdcage head coil at 7 Tesla under consideration of the minimum distance to decouple multiple aneurysm clips JF - Magnetic Resonance in Medicine Y1 - 2019 U6 - http://dx.doi.org/10.1002/mrm.27835 SN - 1522-2594 IS - Early view SP - 1 EP - 17 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Noureddine, Yacine A1 - Bitz, Andreas A1 - Ladd, Mark E. A1 - Thürling, Markus A1 - Ladd, Susanne C. A1 - Schaefers, Gregor A1 - Kraff, Oliver T1 - Experience with magnetic resonance imaging of human subjects with passive implants and tattoos at 7 T: a retrospective study JF - Magnetic Resonance Materials in Physics, Biology and Medicine Y1 - 2015 U6 - http://dx.doi.org/10.1007/s10334-015-0499-y SN - 1352-8661 VL - 28 IS - 6 SP - 577 EP - 590 PB - Springer CY - Berlin ER - TY - JOUR A1 - Niemüller, Tim A1 - Lakemeyer, Gerhard A1 - Ferrein, Alexander A1 - Reuter, S. A1 - Ewert, D. A1 - Jeschke, S. A1 - Pensky, D. A1 - Karras, Ulrich T1 - Proposal for advancements to the LLSF in 2014 and beyond Y1 - 2013 SP - Publ. online ER - TY - JOUR A1 - Niemüller, Tim A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard T1 - A Lua-based Behavior Engine for Controlling the Humanoid Robot Nao JF - RoboCup 2009: Robot Soccer World Cup XIII Y1 - 2010 N1 - Lecture Notes in Computer Science ; 5949 SP - 240 EP - 251 ER - TY - JOUR A1 - Niemüller, Tim A1 - Ferrein, Alexander A1 - Eckel, Gerhard A1 - Pirro, David A1 - Podbregar, Patrick A1 - Kellner, Tobias A1 - Rath, Christoph A1 - Steinbauer, Gerald T1 - Providing Ground-truth Data for the Nao Robot Platform JF - RoboCup 2010: Robot Soccer World Cup XIV Y1 - 2011 SN - 978-3-642-20217-9 N1 - Lecture Notes in Computer Science ; 6556 SP - 133 EP - 144 PB - Springer CY - Berlin ER - TY - JOUR A1 - Niemüller, Tim A1 - Ferrein, Alexander A1 - Beck, Daniel A1 - Lakemeyer, Gerhard T1 - Design Principles of the Component-Based Robot Software Framework Fawkes JF - Simulation, Modeling, and Programming for Autonomous Robots Y1 - 2010 N1 - Lecture Notes in Computer Science ; 6472 ; Second International Conference, SIMPAR 2010, Darmstadt, Germany, November 15-18, 2010. Proceedings SP - 300 EP - 311 ER - TY - JOUR A1 - Ndoumbè Mbonjo Mbonjo, H. A1 - Streckert, J. A1 - Bitz, Andreas A1 - Hansen, V. A1 - Glasmachers, A. A1 - Gencol, S. A1 - Rozic, D. T1 - Generic UMTS test signal for RF bioelectromagnetic studies JF - Bioelectromagnetics Y1 - 2004 U6 - http://dx.doi.org/10.1002/bem.20007 SN - 1521-186X VL - 25 IS - 6 SP - 415 EP - 425 ER - TY - JOUR A1 - Müller, Tim M. A1 - Leise, Philipp A1 - Lorenz, Imke-Sophie A1 - Altherr, Lena A1 - Pelz, Peter F. T1 - Optimization and validation of pumping system design and operation for water supply in high-rise buildings JF - Optimization and Engineering N2 - The application of mathematical optimization methods for water supply system design and operation provides the capacity to increase the energy efficiency and to lower the investment costs considerably. We present a system approach for the optimal design and operation of pumping systems in real-world high-rise buildings that is based on the usage of mixed-integer nonlinear and mixed-integer linear modeling approaches. In addition, we consider different booster station topologies, i.e. parallel and series-parallel central booster stations as well as decentral booster stations. To confirm the validity of the underlying optimization models with real-world system behavior, we additionally present validation results based on experiments conducted on a modularly constructed pumping test rig. Within the models we consider layout and control decisions for different load scenarios, leading to a Deterministic Equivalent of a two-stage stochastic optimization program. We use a piecewise linearization as well as a piecewise relaxation of the pumps’ characteristics to derive mixed-integer linear models. Besides the solution with off-the-shelf solvers, we present a problem specific exact solving algorithm to improve the computation time. Focusing on the efficient exploration of the solution space, we divide the problem into smaller subproblems, which partly can be cut off in the solution process. Furthermore, we discuss the performance and applicability of the solution approaches for real buildings and analyze the technical aspects of the solutions from an engineer’s point of view, keeping in mind the economically important trade-off between investment and operation costs. KW - Technical Operations Research KW - MINLP KW - MILP KW - Experimental validation KW - Pumping systems Y1 - 2020 U6 - http://dx.doi.org/10.1007/s11081-020-09553-4 SN - 1573-2924 VL - 2021 IS - 22 SP - 643 EP - 686 PB - Springer ER - TY - JOUR A1 - Mühl, Thomas A1 - Binnebösel, Marcel A1 - Klinge, Uwe A1 - Goedderz, Thomas T1 - New objective measurement to characterize the porosity of textile implants JF - Journal of Biomedical Materials Research Part B: Applied Biomaterials. 84B (2008), H. 1 Y1 - 2008 SN - 1552-4981 SP - 176 EP - 183 ER - TY - JOUR A1 - Mayer, Claudia T1 - L'Estétique et le pouvoir: Le discours chaotique de l'Allemagne unifiée JF - Canadian review of comparative literature : CRCL = Revue canadienne de littérature comparée : RCLC / Canadian Comparative Literature Association. 24 (1997), H. 2 Y1 - 1997 SN - 0319-051X SP - 297 EP - 317 ER - TY - JOUR A1 - Mayer, Claudia T1 - Between Trans- and Interdisciplinarity. »Germanistik« and the Dialectic of Inclusion and Exclusion of the Other(s) JF - Language and literature today : proceedings of the XIXth triennal congress of the International Federation for Modern Languages and Literatures ; Brasília 22 - 30 August 1993. General ed. Neide de Faria. Y1 - 1993 SN - 85-230-0405-x N1 - Band 2 SP - 958 EP - 966 PB - Univ. CY - Brasilia ER - TY - JOUR A1 - Mayer, Claudia T1 - Between Resistance and Affirmation: Christa Wolf and German Unification JF - Canadian review of comparative literature : CRCL = Revue canadienne de littérature comparée / Canadian Comparative Literature Association. 22 (1995), H. 3-4 Y1 - 1995 SN - 0319-051X SP - 813 EP - 835 ER - TY - JOUR A1 - Maus, Stefan A1 - Höfken, Hans-Wilhelm A1 - Schuba, Marko T1 - Forensic Analysis of Geodata in Android Smartphones Y1 - 2011 N1 - Cyberforensics 2011, Glasgow SP - 1 EP - 11 ER - TY - JOUR A1 - Maas, Marnix C. A1 - Vos, Eline K. A1 - Lagemaat, Miriam W. A1 - Bitz, Andreas A1 - Orzada, Stephan A1 - Kobus, Thiele A1 - Kraff, Oliver A1 - Maderwald, Stefan A1 - Ladd, Mark E. A1 - Scheenen, Tom W. J. T1 - Feasibility of T₂-weighted turbo spin echo imaging of the human prostate at 7 tesla JF - Magnetic Resonance in Medicine N2 - Purpose To demonstrate that high quality T₂-weighted (T2w) turbo spin-echo (TSE) imaging of the complete prostate can be achieved routinely and within safety limits at 7 T, using an external transceive body array coil only. Methods Nine healthy volunteers and 12 prostate cancer patients were scanned on a 7 T whole-body system. Preparation consisted of B₀ and radiofrequency shimming and localized flip angle calibration. T₁ and T₂ relaxation times were measured and used to define the T2w-TSE protocol. T2w imaging was performed using a TSE sequence (pulse repetition time/echo time 3000–3640/71 ms) with prolonged excitation and refocusing pulses to reduce specific absorption rate. Results High quality T2w TSE imaging was performed in less than 2 min in all subjects. Tumors of patients with gold-standard tumor localization (MR-guided biopsy or prostatectomy) were well visualized on 7 T imaging (n = 3). The number of consecutive slices achievable within a 10-g averaged specific absorption rate limit of 10 W/kg was ≥28 in all subjects, sufficient for full prostate coverage with 3-mm slices in at least one direction. Conclusion High quality T2w TSE prostate imaging can be performed routinely and within specific absorption rate limits at 7 T with an external transceive body array. Y1 - 2014 U6 - http://dx.doi.org/10.1002/mrm.24818 SN - 1522-2594 VL - 71 IS - 5 SP - 1711 EP - 1719 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Limpert, Nicolas A1 - Wiesen, Patrick A1 - Ferrein, Alexander A1 - Kallweit, Stephan A1 - Schiffer, Stefan T1 - The ROSIN Project and its Outreach to South Africa JF - R&D Journal Y1 - 2019 VL - 35 SP - 1 EP - 6 ER - TY - JOUR A1 - Lerchl, Alexander A1 - Krüger, Heike A1 - Niehaus, Michael A1 - Streckert, Joachim R. A1 - Bitz, Andreas A1 - Hansen, Volkert T1 - Effects of mobile phone electromagnetic fields at nonthermal SAR values on melatonin and body weight of Djungarian hamsters (Phodopus sungorus) JF - Journal of Pineal Research Y1 - 2008 U6 - http://dx.doi.org/10.1111/j.1600-079X.2007.00522.x SN - 1600-079X VL - 44 IS - 3 SP - 267 EP - 272 ER - TY - JOUR A1 - Leise, Philipp A1 - Eßer, Arved A1 - Eichenlaub, Tobias A1 - Schleiffer, Jean-Eric A1 - Altherr, Lena A1 - Rinderknecht, Stephan A1 - Pelz, Peter F. T1 - Sustainable system design of electric powertrains - comparison of optimization methods JF - Engineering Optimization N2 - The transition within transportation towards battery electric vehicles can lead to a more sustainable future. To account for the development goal ‘climate action’ stated by the United Nations, it is mandatory, within the conceptual design phase, to derive energy-efficient system designs. One barrier is the uncertainty of the driving behaviour within the usage phase. This uncertainty is often addressed by using a stochastic synthesis process to derive representative driving cycles and by using cycle-based optimization. To deal with this uncertainty, a new approach based on a stochastic optimization program is presented. This leads to an optimization model that is solved with an exact solver. It is compared to a system design approach based on driving cycles and a genetic algorithm solver. Both approaches are applied to find efficient electric powertrains with fixed-speed and multi-speed transmissions. Hence, the similarities, differences and respective advantages of each optimization procedure are discussed. KW - Powertrain KW - stochastic optimization KW - global optimization KW - genetic algorithm Y1 - 2021 U6 - http://dx.doi.org/10.1080/0305215X.2021.1928660 SN - 0305-215X PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Leingartner, Max A1 - Maurer, Johannes A1 - Ferrein, Alexander A1 - Steinbauer, Gerald T1 - Evaluation of Sensors and Mapping Approaches for Disasters in Tunnels JF - Journal of Field Robotics N2 - Ground or aerial robots equipped with advanced sensing technologies, such as three-dimensional laser scanners and advanced mapping algorithms, are deemed useful as a supporting technology for first responders. A great deal of excellent research in the field exists, but practical applications at real disaster sites are scarce. Many projects concentrate on equipping robots with advanced capabilities, such as autonomous exploration or object manipulation. In spite of this, realistic application areas for such robots are limited to teleoperated reconnaissance or search. In this paper, we investigate how well state-of-the-art and off-the-shelf components and algorithms are suited for reconnaissance in current disaster-relief scenarios. The basic idea is to make use of some of the most common sensors and deploy some widely used algorithms in a disaster situation, and to evaluate how well the components work for these scenarios. We acquired the sensor data from two field experiments, one from a disaster-relief operation in a motorway tunnel, and one from a mapping experiment in a partly closed down motorway tunnel. Based on these data, which we make publicly available, we evaluate state-of-the-art and off-the-shelf mapping approaches. In our analysis, we integrate opinions and replies from first responders as well as from some algorithm developers on the usefulness of the data and the limitations of the deployed approaches, respectively. We discuss the lessons we learned during the two missions. These lessons are interesting for the community working in similar areas of urban search and rescue, particularly reconnaissance and search. Y1 - 2016 U6 - http://dx.doi.org/10.1002/rob.21611 SN - 1556-4967 VL - 33 IS - 8 SP - 1037 EP - 1057 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Lagemaat, Miriam W. A1 - Vos, Eline K. A1 - Maas, Marnix C. A1 - Bitz, Andreas A1 - Orzada, Stephan A1 - Uden, Mark J. van A1 - Kobus, Thiele A1 - Heerschap, Arend A1 - Scheenen, Tom W. J. T1 - Phosphorus magnetic resonance spectroscopic imaging at 7 T in patients with prostate cancer JF - Investigative Radiology N2 - Objectives The aim of this study was to identify characteristics of phosphorus (³¹P) spectra of the human prostate and to investigate changes of individual phospholipid metabolites in prostate cancer through in vivo ³¹P magnetic resonance spectroscopic imaging (MRSI) at 7 T. Materials and Methods In this institutional review board–approved study, 15 patients with biopsy-proven prostate cancer underwent T₂-weighted magnetic resonance imaging and 3-dimensional ³¹P MRSI at 7 T. Voxels were selected at the tumor location, in normal-appearing peripheral zone tissue, normal-appearing transition zone tissue, and in the base of the prostate close to the seminal vesicles. Phosphorus metabolite ratios were determined and compared between tissue types. Results Signals of phosphoethanolamine (PE) and phosphocholine (PC) were present and well resolved in most ³¹P spectra in the prostate. Glycerophosphocholine signals were observable in 43% of the voxels in malignant tissue, but in only 10% of the voxels in normal-appearing tissue away from the seminal vesicles. In many spectra, independent of tissue type, 2 peaks resonated in the chemical shift range of inorganic phosphate, possibly representing 2 separate pH compartments. The PC/PE ratio in the seminal vesicles was highly elevated compared with the prostate in 5 patients. A considerable overlap of ³¹P metabolite ratios was found between prostate cancer and normal-appearing prostate tissue, preventing direct discrimination of these tissues. The only 2 patients with high Gleason scores tumors (≥4+5) presented with high PC and glycerophosphocholine levels in their cancer lesions. Conclusions Phosphorus MRSI at 7 T shows distinct features of phospholipid metabolites in the prostate gland and its surrounding structures. In this exploratory study, no differences in ³¹P metabolite ratios were observed between prostate cancer and normal-appearing prostate tissue possibly because of the partial volume effects of small tumor foci in large MRSI voxels. Y1 - 2014 U6 - http://dx.doi.org/10.1097/RLI.0000000000000012 SN - 1536-0210 VL - 49 IS - 5 SP - 363 EP - 372 PB - Lippincott Williams & Wilkins CY - Philadelphia, Pa. ER -