TY - JOUR A1 - Dieringer, Matthias A. A1 - Renz, Wolfgang A1 - Lindel, Tomasz D. A1 - Seifert, Frank A1 - Frauenrath, Tobias A1 - von Knobelsdorf-Brenkenhoff, Florian A1 - Waiczies, Helmar A1 - Hoffmann, Werner A1 - Rieger, Jan A1 - Pfeiffer, Harald A1 - Ittermann, Bernd A1 - Schulz-Menger, Jeanette A1 - Niendorf, Thoralf T1 - Design and application of a four-channel transmit/receive surface coil for functional cardiac imaging at 7T JF - Journal of Magnetic Resonance Imaging N2 - Purpose To design and evaluate a four-channel cardiac transceiver coil array for functional cardiac imaging at 7T. Materials and Methods A four-element cardiac transceiver surface coil array was developed with two rectangular loops mounted on an anterior former and two rectangular loops on a posterior former. specific absorption rate (SAR) simulations were performed and a Burn:x-wiley:10531807:media:JMRI22451:tex2gif-stack-1 calibration method was applied prior to obtain 2D FLASH CINE (mSENSE, R = 2) images from nine healthy volunteers with a spatial resolution of up to 1 × 1 × 2.5 mm3. Results Tuning and matching was found to be better than 10 dB for all subjects. The decoupling (S21) was measured to be >18 dB between neighboring loops, >20 dB for opposite loops, and >30 dB for other loop combinations. SAR values were well within the limits provided by the IEC. Imaging provided clinically acceptable signal homogeneity with an excellent blood-myocardium contrast applying the Burn:x-wiley:10531807:media:JMRI22451:tex2gif-stack-2 calibration approach. Conclusion A four-channel cardiac transceiver coil array for 7T was built, allowing for cardiac imaging with clinically acceptable signal homogeneity and an excellent blood-myocardium contrast. Minor anatomic structures, such as pericardium, mitral, and tricuspid valves and their apparatus, as well as trabeculae, were accurately delineated. Y1 - 2011 U6 - https://doi.org/10.1002/jmri.22451 SN - 1522-2586 VL - 33 IS - 3 SP - 736 EP - 741 PB - Wiley-Liss CY - New York ER - TY - JOUR A1 - Schulte-Tigges, Joschua A1 - Förster, Marco A1 - Nikolovski, Gjorgji A1 - Reke, Michael A1 - Ferrein, Alexander A1 - Kaszner, Daniel A1 - Matheis, Dominik A1 - Walter, Thomas T1 - Benchmarking of various LiDAR sensors for use in self-driving vehicles in real-world environments JF - Sensors N2 - Abstract In this paper, we report on our benchmark results of the LiDAR sensors Livox Horizon, Robosense M1, Blickfeld Cube, Blickfeld Cube Range, Velodyne Velarray H800, and Innoviz Pro. The idea was to test the sensors in different typical scenarios that were defined with real-world use cases in mind, in order to find a sensor that meet the requirements of self-driving vehicles. For this, we defined static and dynamic benchmark scenarios. In the static scenarios, both LiDAR and the detection target do not move during the measurement. In dynamic scenarios, the LiDAR sensor was mounted on the vehicle which was driving toward the detection target. We tested all mentioned LiDAR sensors in both scenarios, show the results regarding the detection accuracy of the targets, and discuss their usefulness for deployment in self-driving cars. KW - Lidar KW - Benchmark KW - Self-driving Y1 - 2022 U6 - https://doi.org/10.3390/s22197146 SN - 1424-8220 N1 - This article belongs to the Special Issue "Sensor Fusion for Vehicles Navigation and Robotic Systems" VL - 22 IS - 19 PB - MDPI CY - Basel ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Fuchs, Katharina A1 - Dieringer, Matthias A. A1 - Özerdem, Celal A1 - Patel, Nishan A1 - Renz, Wolfgang A1 - Greiser, Andreas A1 - Elgeti, Thomas A1 - Niendorf, Thoralf T1 - Detailing the use of magnetohydrodynamic effects for synchronization of MRI with the cardiac cycle: A feasibility study JF - Journal of Magnetic Resonance Imaging N2 - Purpose: To investigate the feasibility of using magnetohydrodynamic (MHD) effects for synchronization of magnetic resonance imaging (MRI) with the cardiac cycle. Materials and Methods: The MHD effect was scrutinized using a pulsatile flow phantom at B0 = 7.0 T. MHD effects were examined in vivo in healthy volunteers (n = 10) for B0 ranging from 0.05–7.0 T. Noncontrast-enhanced MR angiography (MRA) of the carotids was performed using a gated steady-state free-precession (SSFP) imaging technique in conjunction with electrocardiogram (ECG) and MHD synchronization. Results: The MHD potential correlates with flow velocities derived from phase contrast MRI. MHD voltages depend on the orientation between B0 and the flow of a conductive fluid. An increase in the interelectrode spacing along the flow increases the MHD potential. In vivo measurement of the MHD effect provides peak voltages of 1.5 mV for surface areas close to the common carotid artery at B0 = 7.0 T. Synchronization of MRI with the cardiac cycle using MHD triggering is feasible. MHD triggered MRA of the carotids at 3.0 T showed an overall image quality and richness of anatomic detail, which is comparable to ECG-triggered MRAs. Conclusion: This feasibility study demonstrates the use of MHD effects for synchronization of MR acquisitions with the cardiac cycle. J. Magn. Reson. Imaging 2012;36:364–372. © 2012 Wiley Periodicals, Inc. Y1 - 2012 U6 - https://doi.org/10.1002/jmri.23634 SN - 1522-2586 VL - 36 IS - 2 SP - 364 EP - 372 PB - Wiley-Liss CY - New York ER - TY - JOUR A1 - Gräßl, Andreas A1 - Renz, Wolfgang A1 - Hezel, Fabian A1 - Dieringer, Matthias A. A1 - Winter, Lukas A1 - Özerdem, Celal A1 - Rieger, Jan A1 - Kellmann, Peter A1 - Santoro, Davide A1 - Lindel, Tomasz D. A1 - Frauenrath, Tobias A1 - Pfeiffer, Harald A1 - Niendorf, Thoralf T1 - Modular 32-channel transceiver coil array for cardiac MRI at 7.0T JF - Magnetic Resonance in Medicine N2 - Purpose To design and evaluate a modular transceiver coil array with 32 independent channels for cardiac MRI at 7.0T. Methods The modular coil array comprises eight independent building blocks, each containing four transceiver loop elements. Numerical simulations were used for B1+ field homogenization and radiofrequency (RF) safety validation. RF characteristics were examined in a phantom study. The array's suitability for accelerated high spatial resolution two-dimensional (2D) FLASH CINE imaging of the heart was examined in a volunteer study. Results Transmission field adjustments and RF characteristics were found to be suitable for the volunteer study. The signal-to-noise intrinsic to 7.0T together with the coil performance afforded a spatial resolution of 1.1 × 1.1 × 2.5 mm3 for 2D CINE FLASH MRI, which is by a factor of 6 superior to standardized CINE protocols used in clinical practice at 1.5T. The 32-channel transceiver array supports one-dimensional acceleration factors of up to R = 4 without impairing image quality significantly. Conclusion The modular 32-channel transceiver cardiac array supports accelerated and high spatial resolution cardiac MRI. The array is compatible with multichannel transmission and provides a technological basis for future clinical assessment of parallel transmission techniques at 7.0T. Y1 - 2013 U6 - https://doi.org/10.1002/mrm.24903 SN - 1522-2594 VL - 72 IS - 1 SP - 276 EP - 290 PB - Wiley-Liss CY - New York ER - TY - JOUR A1 - Bragard, G. A1 - Bragard, Michael T1 - Ein kostengünstiges, universelles Modellbauinterface JF - Der mathematische und naturwissenschaftliche Unterricht : MNU ; Organ des Deutschen Vereins zur Förderung des Mathematischen und Naturwissenschaftlichen Unterrichts e.V. N2 - Wir stellen einen USB-Baustein vor, der eine kostengünstige und universelle Möglichkeit schafft , im Unterricht den Themenkreis Messen-Steuern-Regeln zu behandeln. Die Funktionalität orientiert sich am CVK-Interface der Firma Fischertechnik. Im Gegensatz zu kommerziellen Lösungen erlaubt unser Aufbau auch den preiswerten Einsatz in Gruppen- oder Einzelarbeit. Abschließend berichten wir über ein Beispiel aus dem Unterrichtseinsatz. Y1 - 2012 SN - 0025-5866 VL - 65 IS - 5 SP - 290 EP - 293 PB - Seeberger CY - Neuss ER - TY - JOUR A1 - Droop, Philipp A1 - Chen, Shaohuang A1 - Radford, Melissa J. A1 - Paulßen, Elisabeth A1 - Gates, Byron D. A1 - Reilly, Raymond M. A1 - Radchenko, Valery A1 - Hoehr, Cornelia T1 - Synthesis of 197m/gHg labelled gold nanoparticles for targeted radionuclide therapy JF - Radiochimica Acta N2 - Meitner-Auger-electron emitters have a promising potential for targeted radionuclide therapy of cancer because of their short range and the high linear energy transfer of Meitner-Auger-electrons (MAE). One promising MAE candidate is 197m/gHg with its half-life of 23.8 h and 64.1 h, respectively, and high MAE yield. Gold nanoparticles (AuNPs) that are labelled with 197m/gHg could be a helpful tool for radiation treatment of glioblastoma multiforme when infused into the surgical cavity after resection to prevent recurrence. To produce such AuNPs, 197m/gHg was embedded into pristine AuNPs. Two different syntheses were tested starting from irradiated gold containing trace amounts of 197m/gHg. When sodium citrate was used as reducing agent, no 197m/gHg labelled AuNPs were formed, but with tannic acid, 197m/gHg labeled AuNPs were produced. The method was optimized by neutralizing the pH (pH = 7) of the Au/197m/gHg solution, which led to labelled AuNPs with a size of 12.3 ± 2.0 nm as measured by transmission electron microscopy. The labelled AuNPs had a concentration of 50 μg (gold)/mL with an activity of 151 ± 93 kBq/mL (197gHg, time corrected to the end of bombardment). KW - 197m/gHg KW - Gold nanoparticle (AuNP) KW - Meitner-Auger-electron (MAE) KW - Targeted radionuclide therapy (TRT) Y1 - 2023 U6 - https://doi.org/10.1515/ract-2023-0144 SN - 2193-3405 VL - 111 IS - 10 SP - 773 EP - 779 PB - De Gruyter CY - Berlin [u.a.] ER - TY - JOUR A1 - Heuermann, Holger T1 - Calibration procedures with series impedances and unknown lines simplify on-wafer measurements JF - IEEE transactions on microwave theory and techniques : MTT ; a publication of the IEEE Microwave Theory and Techniques Society. 47 (1999), H. 1 Y1 - 1999 SN - 0018-9480 SP - 1 EP - 5 ER - TY - JOUR A1 - Heuermann, Holger A1 - Schiek, B. T1 - Error corrected impedance measurements with a network analyzer JF - IEEE transactions on instrumentation and measurement : IM / Institute of Electrical and Electronics Engineers, Instrumentation and Measurement Group. 44 (1995), H. 2 Y1 - 1995 SN - 0018-9456 SP - 295 EP - 299 ER - TY - JOUR A1 - Wolf, Martin R. A1 - Simon, S. A1 - Schlick, Christopher T1 - Qualitative and Quantitative Analysis of Cooperation / Wolf, M. ; Simon, S. ; Schlick, C. JF - Proceedings : May 26 - 29, 1998, Cannes (France) = Actes : 26 - 29 mai 1998 / INRIA, Institut National de Recherche en Informatique et en Automatique, Unité de recherche ... F. Darses ..., eds Y1 - 1998 N1 - COOP ; Institut National de Recherche en Informatique et en Automatique ; Centre ; (Sophia Antipolis) ; International Conference on the Design of Cooperative Systems ; (3 ; 1998.05.26-29 ; Cannes) ; Conference Internationale sur la Conception de Systèmes Coopératifs ; (3 ; 1998.05.26-29 ; Cannes) ; COOP ; (3 ; 1998.05.26-29 ; Cannes) SP - 1 EP - 5 PB - - CY - Cannes ER - TY - JOUR A1 - Ritz, Thomas T1 - Personalized Information Services: Production and Distribution of these Services employing Mass-Customization Y1 - 2002 N1 - International Congress on Mass Media and Communications in the e-society of the 21st Century, Moskau, 17.-19.10.2002 ER - TY - JOUR A1 - Heuermann, Holger A1 - Schiek, Burkhard T1 - Robuster Algorithmus zur Streuparameterbestimmung für systemfehlerkorrigierte Netzwerkanalysatoren JF - Kleinheubacher Berichte : Vorträge und Berichte der gemeinsamen Tagung des U.R.S.I.-Landesausschusses in der Bundesrepublik Deutschland / Hrsg.: Deutsche Telekom AG. 35. 1991 (1991) Y1 - 1991 SP - 555 EP - 556 ER - TY - JOUR A1 - Wolf, Martin R. A1 - Foltz, Christian A1 - Killich, Stephan A1 - Schmidt, Ludger T1 - Task and Information Modeling for Cooperative Work / Foltz, Christian ; Killich, Stephan ; Wolf, Martin ; Schmidt, Ludger ; Luczak, Holger JF - Systems, social and internationalization design aspects of human-computer interaction / ed. by Michael J. Smith, Gavriel Salvendy Vol. 2 Y1 - 2001 SN - 0-8058-3608-X N1 - International Conference on Human Computer Interaction 9, 2001, New Orleans, La. SP - 172 EP - 176 PB - - ER - TY - JOUR A1 - Heuermann, Holger A1 - Sadeghfam, Arash T1 - Novel balanced inductor for compact differential systems / Sadeghfam, Arash; Heuermann, Holger JF - Conference proceedings : Tuesday 12th, Wednesday 13th and Thursday 14th October, [RAI International Exhibition and Congress Centre, Amsterdam ; part of European Microwave Week 2004] / EuMA, European Microwave Association Y1 - 2004 SN - 1-580-53992-0 N1 - European Microwave Conference ; (34, 2004, Amsterdam) ; European Microwave Week ; (7, 2004, Amsterdam) SP - 709 EP - 712 PB - Horizon House Publ. CY - London ER - TY - JOUR A1 - Heuermann, Holger A1 - Schiek, Burkhard T1 - Error Corrected Impedance Measurements with a Network Analyzer Y1 - 1994 N1 - 1994 Conference on Precision Electromagnetic Measurements digest : 27 June - 1 July 1994, Boulder, Colorado, USA / Organized by National Institute of Standards and Technology. Ed. by Edie DeWeese SP - 125 EP - 126 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 - Grande, Marion A1 - Meffert, Elisabeth A1 - Schoenberger, Eva A1 - Jung, Stefanie A1 - Frauenrath, Tobias A1 - Huber, Walter A1 - Hussmann, Katja A1 - Moormann, Mareike A1 - Heim, Stefan T1 - From a concept to a word in a syntactically complete sentence: An fMRI study on spontaneous language production in an overt picture description task JF - NeuroImage N2 - Spontaneous language has rarely been subjected to neuroimaging studies. This study therefore introduces a newly developed method for the analysis of linguistic phenomena observed in continuous language production during fMRI. Most neuroimaging studies investigating language have so far focussed on single word or — to a smaller extent — sentence processing, mostly due to methodological considerations. Natural language production, however, is far more than the mere combination of words to larger units. Therefore, the present study aimed at relating brain activation to linguistic phenomena like word-finding difficulties or syntactic completeness in a continuous language fMRI paradigm. A picture description task with special constraints was used to provoke hesitation phenomena and speech errors. The transcribed speech sample was segmented into events of one second and each event was assigned to one category of a complex schema especially developed for this purpose. The main results were: conceptual planning engages bilateral activation of the precuneus. Successful lexical retrieval is accompanied – particularly in comparison to unsolved word-finding difficulties – by the left middle and superior temporal gyrus. Syntactic completeness is reflected in activation of the left inferior frontal gyrus (IFG) (area 44). In sum, the method has proven to be useful for investigating the neural correlates of lexical and syntactic phenomena in an overt picture description task. This opens up new prospects for the analysis of spontaneous language production during fMRI. Y1 - 2012 U6 - https://doi.org/10.1016/j.neuroimage.2012.03.087 SN - 1522-2586 VL - 61 IS - 3 SP - 702 EP - 714 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bragard, Michael A1 - Conrad, M. A1 - van Hoek, H. A1 - De Doncker, R. W. T1 - The integrated emitter turn-off thyristor (IETO) : an innovative thyristor-based high power semiconductor device using MOS assisted turn-off JF - IEEE transactions on industry applications Y1 - 2011 U6 - https://doi.org/10.1109/TIA.2011.2161432 SN - 0093-9994 VL - 47 IS - 5 SP - 2175 EP - 2182 PB - IEEE CY - New York ER - TY - JOUR A1 - Kob, Malte A1 - Frauenrath, Tobias T1 - A system for parallel measurement of glottis opening and larynx position JF - Biomedical Signal Processing and Control N2 - The simultaneous assessment of glottal dynamics and larynx position can be beneficial for the diagnosis of disordered voice or speech production and swallowing. Up to now, methods either concentrate on assessment of the glottis opening using optical, acoustical or electrical (electroglottography, EGG) methods, or on visualisation of the larynx position using ultrasound, computer tomography or magnetic resonance imaging techniques. The method presented here makes use of a time-multiplex measurement approach of space-resolved transfer impedances through the larynx. The fast sequence of measurements allows a quasi simultaneous assessment of both larynx position and EGG signal using up to 32 transmit–receive signal paths. The system assesses the dynamic opening status of the glottis as well as the vertical and back/forward motion of the larynx. Two electrode-arrays are used for the measurement of the electrical transfer impedance through the neck in different directions. From the acquired data the global and individual conductivity is calculated as well as a 2D point spatial representation of the minimum impedance. The position information is shown together with classical EGG signals allowing a synchronous visual assessment of glottal area and larynx position. A first application to singing voice analysis is presented that indicate a high potential of the method for use as a non-invasive tool in the diagnosis of voice, speech, and swallowing disorders. KW - EGG KW - Transfer impedance KW - Tomography KW - Larynx position KW - Voice assessment Y1 - 2009 U6 - https://doi.org/10.1016/j.bspc.2009.03.004 SN - 1746-8108 VL - 4 IS - 3 SP - 221 EP - 228 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wiegner, Jonas A1 - Volker, Hanno A1 - Mainz, Fabian A1 - Backes, Andreas A1 - Loeken, Michael A1 - Hüning, Felix T1 - Energy analysis of a wireless sensor node powered by a Wiegand sensor JF - Journal of Sensors and Sensor Systems (JSSS) N2 - This article describes an Internet of things (IoT) sensing device with a wireless interface which is powered by the energy-harvesting method of the Wiegand effect. The Wiegand effect, in contrast to continuous sources like photovoltaic or thermal harvesters, provides small amounts of energy discontinuously in pulsed mode. To enable an energy-self-sufficient operation of the sensing device with this pulsed energy source, the output energy of the Wiegand generator is maximized. This energy is used to power up the system and to acquire and process data like position, temperature or other resistively measurable quantities as well as transmit these data via an ultra-low-power ultra-wideband (UWB) data transmitter. A proof-of-concept system was built to prove the feasibility of the approach. The energy consumption of the system during start-up was analysed, traced back in detail to the individual components, compared to the generated energy and processed to identify further optimization options. Based on the proof of concept, an application prototype was developed. Y1 - 2023 U6 - https://doi.org/10.5194/jsss-12-85-2023 SN - 2194-878X N1 - Corresponding author: Felix Hüning VL - 12 IS - 1 SP - 85 EP - 92 PB - Copernicus Publ. CY - Göttingen ER - TY - JOUR A1 - Klinge, Uwe A1 - Otto, Jens A1 - Mühl, Thomas T1 - High Structural Stability of Textile Implants Prevents Pore Collapse and Preserves Effective Porosity at Strain JF - BioMed Research International Y1 - 2015 U6 - https://doi.org/10.1155/2015/953209 SN - 2314-6133 (Print) SN - 2314-6141 (Online) N1 - Article ID: 953209 VL - 2015 ER -