@article{vonKnobelsdorfBrenkenhoffFrauenrathProthmannetal.2010, author = {von Knobelsdorf-Brenkenhoff, Florian and Frauenrath, Tobias and Prothmann, Marcel and Dieringer, Matthias A. and Hezel, Fabian and Renz, Wolfgang and Kretschel, Kerstin and Niendorf, Thoralf and Schulz-Menger, Jeanette}, title = {Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla—a pilot study}, volume = {20}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {0938-7994}, doi = {10.1007/s00330-010-1888-2}, pages = {2844 -- 2852}, year = {2010}, abstract = {Objectives Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T. Methods A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated. Results All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm. Conclusions This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T.}, language = {en} } @misc{LindelGreiserWaxmanetal.2012, author = {Lindel, Tomasz Dawid and Greiser, Andreas and Waxman, Patrick and Dietterle, Martin and Seifert, Frank and Fontius, Ulrich and Renz, Wolfgang and Dieringer, Matthias A. and Frauenrath, Tobias and Schulz-Menger, Jeanette and Niendorf, Thoralf and Ittermann, Bernd}, title = {Cardiac CINE MRI at 7 T using a transmit array}, series = {2012 ISMRM Annual Meeting Proceedings}, journal = {2012 ISMRM Annual Meeting Proceedings}, issn = {1545-4428}, year = {2012}, abstract = {With its need for high SNR and short acquisition times, Cardiac MRI (CMR) is an intriguing target application for ultrahigh field MRI. Due to the sheer size of the upper torso, however, the known RF issues of 7T MRI are also most prominent in CMR. Recent years brought substantial progress but the full potential of the ultrahigh field for CMR is yet to be exploited. Parallel transmission (pTx) is a promising approach in this context and several groups have already reported B1 shimming for 7T CMR. In such a static pTx application amplitudes and phases of all Tx channels are adjusted individually but otherwise imaging techniques established in current clinical practice 1.5 T and 3 T are applied. More advanced forms of pTx as spatially selective excitation (SSE) using Transmit SENSE promise additional benefits like faster imaging with reduced fields of view or improved SAR control. SSE requires the full dynamic capabilities of pTx, however, and for the majority of today's implemented pTx hardware the internal synchronization of the Tx array does not easily permit external triggering as needed for CMR. Here we report a software solution to this problem and demonstrate the feasibility of CINE CMR at 7 T using a Tx array.}, 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} } @misc{NoetzoldBragardFinketal.2014, author = {N{\"o}tzold, K. and Bragard, Michael and Fink, K. and Griessel, R. and Wegener, R.}, title = {Cascaded H-bridge converter with transformer based cell power balancing in each voltage level : [Patentschrift]}, publisher = {Europ{\"a}isches Patentamt / United States Patent and Trademark Office [u.a.]}, address = {Den Haag / Alexandria, VA}, pages = {16 S. : graph. Darst.}, year = {2014}, language = {en} } @inproceedings{SchifferBragard2019, author = {Schiffer, Fabian and Bragard, Michael}, title = {Cascaded LQ and Field-Oriented Control of a Mobile Inverse Pendulum (Segway) with Permanent Magnet Synchronous Machines}, series = {2019 20th International Conference on Research and Education in Mechatronics (REM)}, booktitle = {2019 20th International Conference on Research and Education in Mechatronics (REM)}, isbn = {978-1-5386-9257-8}, doi = {10.1109/REM.2019.8744101}, pages = {1 -- 8}, year = {2019}, language = {en} } @article{HagemannHenningsWernicke1984, author = {Hagemann, Hans-J{\"u}rgen and Hennings, D. and Wernicke, R.}, title = {Ceramic multilayer capacitors. Hagemann, H. J.; Hennings, D.; Wernicke, R.}, series = {Philips' technical review / Philips' Gloeilampenfabrieken. Philips' Gloeilampenfabrieken . 41 (1984)}, journal = {Philips' technical review / Philips' Gloeilampenfabrieken. Philips' Gloeilampenfabrieken . 41 (1984)}, isbn = {0031-7926}, pages = {89 -- 98}, year = {1984}, language = {en} } @article{HaagZontarSchleupenetal.2014, author = {Haag, S. and Zontar, D. and Schleupen, Josef and M{\"u}ller, T. and Brecher, C.}, title = {Chain of refined perception in self-optimizing assembly of micro-optical systems}, series = {Journal of sensors and sensor systems}, volume = {3}, journal = {Journal of sensors and sensor systems}, number = {1}, publisher = {Copernicus Publ.}, address = {G{\"o}ttingen}, issn = {2194-878X}, doi = {10.5194/jsss-3-87-2014}, pages = {87 -- 95}, year = {2014}, abstract = {Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements - especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base.}, language = {en} } @article{SerrorHackHenzeetal.2021, author = {Serror, Martin and Hack, Sacha and Henze, Martin and Schuba, Marko and Wehrle, Klaus}, title = {Challenges and Opportunities in Securing the Industrial Internet of Things}, series = {IEEE Transactions on Industrial Informatics}, volume = {17}, journal = {IEEE Transactions on Industrial Informatics}, number = {5}, publisher = {IEEE}, address = {New York}, issn = {1941-0050}, doi = {10.1109/TII.2020.3023507}, pages = {2985 -- 2996}, year = {2021}, language = {en} } @article{SchollAachDesernoetal.2011, author = {Scholl, Ingrid and Aach, Til and Deserno, Thomas M. and Kuhlen, Torsten}, title = {Challenges of medical image processing}, series = {Computer Science - Research and Development}, volume = {26}, journal = {Computer Science - Research and Development}, number = {1-2}, publisher = {Springer}, address = {Berlin}, isbn = {1865-2042}, pages = {5 -- 13}, year = {2011}, language = {en} } @article{HoltrupSadeghfamHeuermannetal.2014, author = {Holtrup, S. and Sadeghfam, Arash and Heuermann, Holger and Awakowicz, P.}, title = {Characterization and optimization technique for microwave-driven high-intensity discharge lamps using hot S-parameters}, series = {IEEE transactions on microwave theories and techniques}, volume = {62}, journal = {IEEE transactions on microwave theories and techniques}, number = {10}, publisher = {IEEE}, address = {New York}, issn = {0018-9480}, doi = {10.1109/TMTT.2014.2342652}, pages = {2471 -- 2480}, year = {2014}, abstract = {High-intensity discharge lamps can be driven by radio-frequency signals in the ISM frequency band at 2.45 GHz, using a matching network to transform the impedance of the plasma to the source impedance. To achieve an optimal operating condition, a good characterization of the lamp in terms of radio frequency equivalent circuits under operating conditions is necessary, enabling the design of an efficient matching network. This paper presents the characterization technique for such lamps and presents the design of the required matching network. For the characterization, a high-intensity discharge lamp was driven by a monofrequent large signal at 2.45 GHz, whereas a frequency sweep over 300 MHz was performed across this signal to measure so-called small-signal hot S-parameters using a vector network analyzer. These parameters are then used as an equivalent load in a circuit simulator to design an appropriate matching network. Using the measured data as a black-box model in the simulation results in a quick and efficient method to simulate and design efficient matching networks in spite of the complex plasma behavior. Furthermore, photometric analysis of high-intensity discharge lamps are carried out, comparing microwave operation to conventional operation.}, language = {en} }