@inproceedings{BragardGottschlichDeDoncker2011, author = {Bragard, Michael and Gottschlich, J. and De Doncker, R. W.}, title = {Design and realization of a credit card size driver stage for high power thyristor based devices with integrated MOS structure}, series = {2011 IEEE 8th International Conference on Power Electronics and ECCE Asia (ICPE \& ECCE 2011) : Jeju, South Korea, 30 May 2011 - 3 June 2011 / [co-sponsored by the Korean Institute of Power Electronics ...]}, booktitle = {2011 IEEE 8th International Conference on Power Electronics and ECCE Asia (ICPE \& ECCE 2011) : Jeju, South Korea, 30 May 2011 - 3 June 2011 / [co-sponsored by the Korean Institute of Power Electronics ...]}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-61284-958-4 (Print)}, doi = {10.1109/ICPE.2011.5944661}, pages = {1182 -- 1189}, year = {2011}, language = {en} } @article{FrauenrathHezelRenzetal.2010, author = {Frauenrath, Tobias and Hezel, Fabian and Renz, Wolfgang and de Geyer d'Orth, Thibaut and Dieringer, Matthias and von Knobelsdorf-Brenkenhoff, Florian and Prothmann, Marcel and Schulz-Menger, Jeanette and Niendorf, Thoralf}, title = {Acoustic cardiac triggering: a practical solution for synchronization and gating of cardiovascular magnetic resonance at 7 Tesla}, series = {Journal of Cardiovascular Magnetic Resonance}, volume = {12}, journal = {Journal of Cardiovascular Magnetic Resonance}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1532-429X}, doi = {10.1186/1532-429X-12-67}, year = {2010}, abstract = {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.}, language = {en} } @article{MartinFrauenrathOezerdemetal.2011, author = {Martin, Conrad and Frauenrath, Tobias and {\"O}zerdem, Celal and Renz, Wolfgang and Niendorf, Thoralf}, title = {Development and evaluation of a small and mobile Magneto Alert Sensor (MALSE) to support safety requirements for magnetic resonance imaging}, series = {European Radiology}, volume = {21}, journal = {European Radiology}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {1432-1084}, doi = {10.1007/s00330-011-2153-z}, pages = {2187 -- 2192}, year = {2011}, abstract = {Objective The purpose of this study is to (i) design a small and mobile Magnetic field ALert SEnsor (MALSE), (ii) to carefully evaluate its sensors to their consistency of activation/deactivation and sensitivity to magnetic fields, and (iii) to demonstrate the applicability of MALSE in 1.5 T, 3.0 T and 7.0 T MR fringe field environments. Methods MALSE comprises a set of reed sensors, which activate in response to their exposure to a magnetic field. The activation/deactivation of reed sensors was examined by moving them in/out of the fringe field generated by 7TMR. Results The consistency with which individual reed sensors would activate at the same field strength was found to be 100\% for the setup used. All of the reed switches investigated required a substantial drop in ambient magnetic field strength before they deactivated. Conclusions MALSE is a simple concept for alerting MRI staff to a ferromagnetic object being brought into fringe magnetic fields which exceeds MALSEs activation magnetic field. MALSE can easily be attached to ferromagnetic objects within the vicinity of a scanner, thus creating a barrier for hazardous situations induced by ferromagnetic parts which should not enter the vicinity of an MR-system to occur.}, language = {en} } @inproceedings{PenneProfittlichRingbecketal.2010, author = {Penne, Jochen and Profittlich, Martin and Ringbeck, Thorsten and Buxbaum, Bernd}, title = {Touchless detailed 3D scan of human hand anatomy using time-of-flight cameras}, series = {Proceedings of the International Conference on 3D Body Scanning Technologies : Lugano, Switzerland, 19-20 October 2010}, booktitle = {Proceedings of the International Conference on 3D Body Scanning Technologies : Lugano, Switzerland, 19-20 October 2010}, editor = {D, Nicola D'Apuzzo}, publisher = {Hometrica Consulting}, address = {Z{\"u}rich}, isbn = {978-3-033-02714-5}, pages = {361 -- 369}, year = {2010}, language = {en} } @inproceedings{SchwarteBuxbaumHeinoletal.1998, author = {Schwarte, Rudolf and Buxbaum, Bernd and Heinol, Horst-Guenther and Xu, Zhanping and Ringbeck, Thorsten and Zang, Zhigang}, title = {Novel 3D-vision systems based on layout optimized PMD-structures}, series = {Proceedings / OPTO 98, Internationaler Kongress und Fachausstellung f{\"u}r Optische Sensorik, Messtechnik und Elektronik, 18. - 20. Mai 1998, Kongreßzentrum Erfurt}, booktitle = {Proceedings / OPTO 98, Internationaler Kongress und Fachausstellung f{\"u}r Optische Sensorik, Messtechnik und Elektronik, 18. - 20. Mai 1998, Kongreßzentrum Erfurt}, publisher = {ACS Organisations GmbH}, address = {Wunsdorf}, pages = {197 -- 202}, year = {1998}, language = {en} } @article{DieringerRenzLindeletal.2011, author = {Dieringer, Matthias A. and Renz, Wolfgang and Lindel, Tomasz D. and Seifert, Frank and Frauenrath, Tobias and von Knobelsdorf-Brenkenhoff, Florian and Waiczies, Helmar and Hoffmann, Werner and Rieger, Jan and Pfeiffer, Harald and Ittermann, Bernd and Schulz-Menger, Jeanette and Niendorf, Thoralf}, title = {Design and application of a four-channel transmit/receive surface coil for functional cardiac imaging at 7T}, series = {Journal of Magnetic Resonance Imaging}, volume = {33}, journal = {Journal of Magnetic Resonance Imaging}, number = {3}, publisher = {Wiley-Liss}, address = {New York}, issn = {1522-2586}, doi = {10.1002/jmri.22451}, pages = {736 -- 741}, year = {2011}, abstract = {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.}, language = {en} } @misc{TkachenkovonKnobelsdorffBrenkenhoffKleindienstetal.2012, author = {Tkachenko, Valeriy and von Knobelsdorff-Brenkenhoff, Florian and Kleindienst, Denise and Winter, Lukas and Rieger, Jan and Frauenrath, Tobias and Dieringer, Matthias A. and Santoro, Davide and Niendorf, Thoralf and Schulz-Menger, Jeanette}, title = {Cardiovasular MR at 7Tesla: assessment of the right ventricle}, series = {2012 ISMRM Annual Meeting Proceedings}, journal = {2012 ISMRM Annual Meeting Proceedings}, issn = {1545-4428}, year = {2012}, abstract = {The assessment of the right ventricle (RV) is a challenge in today's cardiology, but of growing clinical impact regarding patient prognosis in different cardiac diseases. The detection and differentiation of small wall motion abnormalities may help to enhance the differentiation of cardiomyopathies including Arrhythmogenic Rightventricular Cardiomyopathy. Cardiovascular magnetic resonance (CMR) at 1.5T is the accepted gold standard for RV quantification. The higher spatial resolution achievable at ultrahigh field strength (UHF) offers the potential to gain new insights into the structure and function of the RV. To approach this goal accurate RV chamber quantification at 7T has to be proven. Consequently this study examines the feasibility of assessment of RV dimensions and function at 7T using improved spatial resolution enabled by the intrinsic sensitivity gain of UHF CMR. For this purpose, a dedicated 16 channel TX/RX RF coil array is used together with 2D CINE fast gradient echo (FGRE) imaging. For comparison RV chamber quantification is conducted at 1.5T using a SSFP based state of the art clinical protocol.}, language = {en} } @inproceedings{LenzWolf2014, author = {Lenz, Laura L. and Wolf, Martin R.}, title = {Economic evaluation of serious games with the comparative assessment framework COSEGA}, series = {The shift from teaching to learning : individual, collective and organizational learning through gaming simulation ; proceedings of the 45th conference of the International Simulation and Gaming Association, Dornbirn 2014}, booktitle = {The shift from teaching to learning : individual, collective and organizational learning through gaming simulation ; proceedings of the 45th conference of the International Simulation and Gaming Association, Dornbirn 2014}, editor = {Kritz, Willy Christian}, publisher = {Bertelsmann}, address = {[Bielefeld]}, isbn = {978-3-7639-5422-3}, pages = {374 -- 386}, year = {2014}, language = {en} } @misc{GraesslRenzHezeletal.2012, author = {Gr{\"a}ßl, Andreas and Renz, Wolfgang and Hezel, Fabian and Frauenrath, Tobias and Pfeiffer, Harald and Hoffmann, Werner and Kellmann, Peter and Martin, Conrad and Niendorf, Thoralf}, title = {Design, evaluation and application of a modular 32 channel transmit/receive surface coil array for cardiac MRI at 7T}, series = {2012 ISMRM Annual Meeting Proceedings}, journal = {2012 ISMRM Annual Meeting Proceedings}, issn = {1545-4428}, year = {2012}, abstract = {Cardiac MR (CMR) at ultrahigh (≥7.0 T) fields is regarded as one of the most challenging MRI applications. At 7.0 T image quality is not always exclusively defined by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Detrimental effects bear the potential to spoil the signal-to-noise (SNR) and contrast-to-noise (CNR) benefits of cardiac MR (CMR) at 7.0 T. B₁⁺-inhomogeneities and signal voids represent the main challenges. Various pioneering coil concepts have been proposed to tackle these issues, enabling cardiac MRI at 7.0 T. This includes a trend towards an ever larger number of transmit and receive channels. This approach affords multi-dimensional B₁⁺ modulations to improve B₁⁺ shimming performance and to enhance RF efficiency. Also, parallel imaging benefits from a high number of receive channels enabling two-dimensional acceleration. Realizing the limitations of existing coil designs tailored for UHF CMR and recognizing the opportunities of a many element TX/RX channel architecture this work proposes a modular, two dimensional 32-channel transmit and receive array using loop elements and examines its efficacy for enhanced B¹+ homogeneity and improved parallel imaging performance.}, language = {en} } @article{SchulteTiggesFoersterNikolovskietal.2022, author = {Schulte-Tigges, Joschua and F{\"o}rster, Marco and Nikolovski, Gjorgji and Reke, Michael and Ferrein, Alexander and Kaszner, Daniel and Matheis, Dominik and Walter, Thomas}, title = {Benchmarking of various LiDAR sensors for use in self-driving vehicles in real-world environments}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {19}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s22197146}, pages = {20 Seiten}, year = {2022}, abstract = {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.}, language = {en} }