TY - JOUR A1 - Ritz, Thomas A1 - Hoof, Antonius J. M. T1 - Personalisierung von Content basierten Services - Produktion von personalisierten Informationsdienstleistungen JF - Content Management : digitale Inhalte als Bausteine einer vernetzten Welt ; 18. Juni 2002, Stuttgart / Innovationsforum. Veranst. Verein zur Förderung Produktionstechnischer Forschung e.V., Stuttgart. [Fraunhofer-Institut Arbeitswirtschaft und Organisatio Y1 - 2002 SN - 3-8167-6155-0 SP - 91 EP - 106 PB - Fraunhofer-IRB-Verl. CY - Stuttgart ER - TY - JOUR A1 - Schuba, Marko A1 - Hermanns, Oliver T1 - Performance Investigations of the IP Multicast Architecture / Hermanns, Oliver ; Schuba, Marko JF - Performance of the IP Multicast Achitecture . Proceedings JENC 6. Proceedings of the 6th Joint European Networking Conference, Tel Aviv Y1 - 1995 N1 - Reprinted in Computer Networks and ISDN Systems 28 pp 429-439, 1996 SP - 121-1 EP - 121-8 ER - TY - JOUR A1 - Schuba, Marko A1 - Haverkort, Boudewijn R. A1 - Schneider, Gaby T1 - Performance evaluation of multicast communication in packet-switched networks / Schuba, Marko ; Haverkort, Boudewijn R. ; Schneider, Gaby JF - Performance Evaluation. 39 (2000), H. 1-4 Y1 - 2000 SN - 0166-5316 N1 - http://dx.doi.org/10.1016/S0166-5316(99)00058-9 SP - 61 EP - 80 ER - TY - JOUR A1 - Fiedler, Thomas M. A1 - Orzada, Stephan A1 - Flöser, Martina A1 - Rietsch, Stefan H. G. A1 - Schmidt, Simon A1 - Stelter, Jonathan K. A1 - Wittrich, Marco A1 - Quick, Harald H. A1 - Bitz, Andreas A1 - Ladd, Mark E. T1 - Performance and safety assessment of an integrated transmit array for body imaging at 7 T under consideration of specificabsorption rate, tissue temperature, and thermal dose JF - NMR in Biomedicine N2 - In this study, the performance of an integrated body-imaging array for 7 T with 32 radiofrequency (RF) channels under consideration of local specific absorption rate (SAR), tissue temperature, and thermal dose limits was evaluated and the imaging performance was compared with a clinical 3 T body coil. Thirty-two transmit elements were placed in three rings between the bore liner and RF shield of the gradient coil. Slice-selective RF pulse optimizations for B1 shimming and spokes were performed for differently oriented slices in the body under consideration of realistic constraints for power and local SAR. To improve the B1+ homogeneity, safety assessments based on temperature and thermal dose were performed to possibly allow for higher input power for the pulse optimization than permissible with SAR limits. The results showed that using two spokes, the 7 T array outperformed the 3 T birdcage in all the considered regions of interest. However, a significantly higher SAR or lower duty cycle at 7 T is necessary in some cases to achieve similar B1+ homogeneity as at 3 T. The homogeneity in up to 50 cm-long coronal slices can particularly benefit from the high RF shim performance provided by the 32 RF channels. The thermal dose approach increases the allowable input power and the corresponding local SAR, in one example up to 100 W/kg, without limiting the exposure time necessary for an MR examination. In conclusion, the integrated antenna array at 7 T enables a clinical workflow for body imaging and comparable imaging performance to a conventional 3 T clinical body coil. KW - body imaging at 7 T MRI KW - thermal dose KW - tissue temperature KW - transmit antenna arrays Y1 - 2022 U6 - https://doi.org/10.1002/nbm.4656 SN - 0952-3480 (Print) SN - 1099-1492 (Online) VL - 35 IS - 5 SP - 1 EP - 17 PB - Wiley ER - TY - JOUR A1 - Schuba, Marko T1 - Performance Analysis of Reliable Multicast Mechanisms for Widely Spread Distributed Applications in the Internet JF - International Conference on Parallel and Distributed Processing Techniques and Applications : PDPTA '99 ; June 28 - July 1, 1999, Las Vegas, Nevada, USA / ed.: Hamid R. Arabnia Y1 - 1999 SN - 1892512157 SP - 1 EP - 7 ER - TY - JOUR A1 - Fiedler, Thomas M. A1 - Orzada, Stephan A1 - Flöser, Martina A1 - Rietsch, Stefan H. G. A1 - Quick, Harald H. A1 - Ladd, Mark E. A1 - Bitz, Andreas T1 - Performance analysis of integrated RF microstrip transmit antenna arrays with high channel count for body imaging at 7 T JF - NMR in Biomedicine N2 - The aim of the current study was to investigate the performance of integrated RF transmit arrays with high channel count consisting of meander microstrip antennas for body imaging at 7 T and to optimize the position and number of transmit ele- ments. RF simulations using multiring antenna arrays placed behind the bore liner were performed for realistic exposure conditions for body imaging. Simulations were performed for arrays with as few as eight elements and for arrays with high channel counts of up to 48 elements. The B1+ field was evaluated regarding the degrees of freedom for RF shimming in the abdomen. Worst-case specific absorption rate (SARwc ), SAR overestimation in the matrix compression, the number of virtual obser- vation points (VOPs) and SAR efficiency were evaluated. Constrained RF shimming was performed in differently oriented regions of interest in the body, and the devia- tion from a target B1+ field was evaluated. Results show that integrated multiring arrays are able to generate homogeneous B1+ field distributions for large FOVs, espe- cially for coronal/sagittal slices, and thus enable body imaging at 7 T with a clinical workflow; however, a low duty cycle or a high SAR is required to achieve homoge- neous B1+ distributions and to exploit the full potential. In conclusion, integrated arrays allow for high element counts that have high degrees of freedom for the pulse optimization but also produce high SARwc , which reduces the SAR accuracy in the VOP compression for low-SAR protocols, leading to a potential reduction in array performance. Smaller SAR overestimations can increase SAR accuracy, but lead to a high number of VOPs, which increases the computational cost for VOP evaluation and makes online SAR monitoring or pulse optimization challenging. Arrays with interleaved rings showed the best results in the study. KW - body imaging at UHF MRI KW - integrated transmit coil arrays KW - VOP compression Y1 - 2021 U6 - https://doi.org/10.1002/nbm.4515 SN - 0952-3480 (ISSN) SN - 1099-1492 (eISSN) VL - 34 IS - 7 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Mühl, Thomas A1 - Schwarz, Michael T1 - Pegel- und Dämpfungsmessung an Wellenlängenmultiplex-Systemen und -Komponenten JF - Nachrichtentechnische Zeitschrift. 46 (1993), H. 1 Y1 - 1993 SN - 0027-707X SP - 36 EP - 38 ER - TY - JOUR A1 - Hagemann, Hans-Jürgen A1 - Geittner, P. T1 - PCVD hybrid technology for single mode fibres. Hagemann, H. J.; Geittner, P. JF - Proceedings : papers presented at: the 8th Annual European Fibre Optic Communications and Local Area Networks Exposition Y1 - 1990 N1 - EFOC LAN <8, 1990, München> SP - 67 EP - 72 ER - TY - JOUR A1 - Hagemann, Hans-Jürgen A1 - Geittner, P. A1 - Warnier, J. A1 - Wilson, H. T1 - PCVD at high deposition rates. Geittner, P.; Hagemann, H. J.; Warnier, J.; Wilson, H. JF - Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 4 (1986), H. 7 Y1 - 1986 SN - 0733-8724 SP - 818 EP - 822 ER - TY - JOUR A1 - Scholl, Ingrid A1 - Conradi, Helmut A1 - Wirtz, D. A1 - Spreckelsen, Cord T1 - OrthoDocs - Ein modellbasiertes Werkzeug zur Erstellung orthopädischer Lerndokumente. Conradi, Helmar; Wirtz, D.; Spreckelsen, Cord; Scholl, Ingrid; Kreutz, Reinhard; Forst, R.; Spitzer, Klaus JF - Medizinische Informatik, Biometrie und Epidemiologie, GMDS '96, 41. Jahrestagung der GMDS, Bonn, September 1996 Y1 - 1997 SN - 3820812954 SP - 169 EP - 173 PB - MVV, Medizin-Verl. CY - München ER -