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  - CHAP
A1  - Fiedler, Gerda
A1  - Gottschlich-Müller, Birgit
A1  - Melcher, Karin
ED  - Liu-Henke, Xiaobo
ED  - Durak, Umut
T1  - Online-Prüfungen mit STACK Aufgaben
T2  - Tagungsband ASIM Workshop STS/GMMS/EDU 2021
N2  - Wir stellen hier exemplarisch STACK Aufgaben vor, die frei von der Problematik sind, welche sich durch diverse Kommunikationswege und (webbasierte) Computer Algebra Systeme (CAS) ergibt. Daher sind sie insbesondere für eine Open-Book Online Prüfung geeignet, da eine faire Prüfungssituation gewährleistet werden kann.
Y1  - 2021
SN  - 978-3-901608-69-8
U6  - https://doi.org/10.11128/arep.45
N1  - Virtueller Workshop, ASIM STS/GMMS & EDU 2021, 11.-12. März 2021
SP  - 173
EP  - 178
PB  - ARGESIM Verlag
CY  - Wien
ER  - 
TY  - BOOK
A1  - Feuerriegel, Uwe
T1  - Wärmeübertragung mit EXCEL und VBA: Wärmetechnische Berechnungen und Simulationen effektiv durchführen und professionell dokumentieren
N2  - Dieses Lehrbuch vermittelt die Grundlagen der Wärmeübertragung sowie den Umgang mit EXCEL-VBA von der Erstellung von Makros bis zu benutzerdefinierten Funktionen. Es legt damit eine Basis für die schnelle und professionelle Durchführung von Berechnungen und Simulationen. Die angeleitete Erstellung von Berechnungsmodulen mit EXCEL und VBA aus allen wichtigen Bereichen der Wärmeübertragung bildet den inhaltlichen Schwerpunkt. Dazu zählen die stationäre Wärmeleitung und der stationäre Wärmedurchgang, die instationäre Wärmeleitung, der Wärmeübergang bei freier und erzwungener Konvektion sowie die Wärmestrahlung und der Wärmeübergang beim Kondensieren und Sieden. Soweit sinnvoll und möglich werden die Stoffwertekorrelationen und die Berechnungsvorschriften aus dem VDI-Wärmeatlas verwendet. Für ausgewählte Anwendungen werden zudem komplexere Auslegungen und Simulationen von Prozessen der Wärmeübertragung sowie von Wärmeübertragern erstellt. Die Zielgruppen: Studierende in Bachelor- und Masterstudiengängen, Praktiker im Engineering
KW  - Wärmeübertragung
KW  - Energietechnik
KW  - Excel und VBA
KW  - VDI-Wärmeatlas
KW  - Wärmeübertrager
Y1  - 2021
SN  - 978-3-658-35905-8
U6  - https://doi.org/10.1007/978-3-658-35906-5
N1  - In der Bereichsbibliothek Eupener Straße unter der Signatur 21 WDW 39 vorhanden
PB  - Springer Vieweg
CY  - Wiesbaden
ER  - 
TY  - CHAP
A1  - Ferrein, Alexander
A1  - Meeßen, Marcus
A1  - Limpert, Nicolas
A1  - Schiffer, Stefan
ED  - Lepuschitz, Wilfried
T1  - Compiling ROS schooling curricula via contentual taxonomies
T2  - Robotics in Education
N2  - The Robot Operating System (ROS) is the current de-facto standard in robot middlewares. The steadily increasing size of the user base results in a greater demand for training as well. User groups range from students in academia to industry professionals with a broad spectrum of developers in between. To deliver high quality training and education to any of these audiences, educators need to tailor individual curricula for any such training. In this paper, we present an approach to ease compiling curricula for ROS trainings based on a taxonomy of the teaching contents. The instructor can select a set of dedicated learning units and the system will automatically compile the teaching material based on the dependencies of the units selected and a set of parameters for a particular training. We walk through an example training to illustrate our work.
Y1  - 2021
SN  - 978-3-030-67411-3
U6  - https://doi.org/10.1007/978-3-030-67411-3_5
N1  - RiE: International Conference on Robotics in Education (RiE);
Advances in Intelligent Systems and Computing book series (AISC, volume 1316)
SP  - 49
EP  - 60
PB  - Springer
CY  - Cham
ER  - 
TY  - JOUR
A1  - Fagan, Andrew J.
A1  - Bitz, Andreas
A1  - Björkman-Burtscher, Isabella M.
A1  - Collins, Christopher M.
A1  - Kimbrell, Vera
A1  - Raaijmakers, Alexander J. E.
T1  - 7T MR Safety
JF  - Journal of Magnetic Resonance Imaging (JMRI)
Y1  - 2021
U6  - https://doi.org/10.1002/jmri.27319
SN  - 1522-2586
VL  - 53
IS  - 2
SP  - 333
EP  - 346
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Erpicum, Sebastien
A1  - Crookston, Brian M.
A1  - Bombardelli, Fabian
A1  - Bung, Daniel Bernhard
A1  - Felder, Stefan
A1  - Mulligan, Sean
A1  - Oertel, Mario
A1  - Palermo, Michele
T1  - Hydraulic structures engineering: An evolving science in a changing world
JF  - Wires Water
Y1  - 2021
U6  - https://doi.org/10.1002/wat2.1505
SN  - 2049-1948
VL  - 8
IS  - 2
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - THES
A1  - Ernst, Loredana
T1  - Let´s change fashion!: Eine Image-Kampagne der Fair Wear Foundation
für faire und nachhaltige Mode.
N2  - Fast Fashion-Ketten beherrschen die Modewelt. Doch einige Unternehmen, Siegel und Stiftungen versuchen die Textilindustrie neu umzugestalten. Um die Modeindustrie nachhaltig zu verändern, müssen allerdings auch den Kunden die schlechten Arbeitsbedingungen und die negativen Einflüsse der Textilbranche auf die Umwelt bewusst werden.
Das konkrete Ziel der erstellten Kampagne ist es, modebewusste Menschen davon zu überzeugen Fast Fashion hinter sich zu lassen. Es soll also ein Umdenken bei den Konsumenten stattfinden. Die Fair Wear Foundation und ihre Mitglieder vertreten die Vision, dass Mode auch fair und nachhaltig sein kann. Genau diese Vision soll mit der Kampagne vermittelt und an die Konsumenten weitergetragen werden.
KW  - Kampagne
KW  - Konzept
KW  - Layout
KW  - Mode
KW  - fair
Y1  - 2021
N1  - Für diese Arbeit steht kein Volltext zur Verfügung.
PB  - FH Aachen
CY  - Aachen
ER  - 
TY  - CHAP
A1  - Englhard, Markus
A1  - Weber, Tobias
A1  - Arent, Jan-Christoph
T1  - Efficiency enhancement for CFRP-Prepregautoclave manufacturing by means of simulation-assisted loading optimization
T2  - Proceedings of SAMPE Europe Conference 2021
N2  - A new method for improved autoclave loading within the restrictive framework of helicopter manufacturing is proposed. It is derived from experimental and numerical studies of the curing process and aims at optimizing tooling positions in the autoclave for fast and homogeneous heat-up. The mold positioning is based on two sets of information. The thermal properties of the molds, which can be determined via semi-empirical thermal simulation. The second information is a previously determined distribution of heat transfer coefficients inside the autoclave. Finally, an experimental proof of concept is performed to show a cycle time reduction of up to 31% using the proposed methodology.
Y1  - 2021
N1  - SAMPE Europe Conference 2021, Baden/Zürich, Schweiz, 29. bis 30. September 2021
ER  - 
TY  - CHAP
A1  - Engelmann, Ulrich M.
A1  - Shasha, Carolyn
A1  - Slabu, Ioana
T1  - Magnetic nanoparticle relaxation in biomedical application: focus on simulating nanoparticle heating
T2  - Magnetic nanoparticles in human health and medicine
Y1  - 2021
SN  - 978-1-119-75467-1
SP  - 327
EP  - 354
PB  - Wiley-Blackwell
CY  - Hoboken, New Jeersey
ER  - 
TY  - JOUR
A1  - Engelmann, Ulrich M.
A1  - Shalaby, Ahmed
A1  - Shasha, Carolyn
A1  - Krishnan, Kannan M.
A1  - Krause, Hans-Joachim
T1  - Comparative modeling of frequency mixing measurements of magnetic nanoparticles using micromagnetic simulations and Langevin theory
JF  - Nanomaterials
N2  - Dual frequency magnetic excitation of magnetic nanoparticles (MNP) enables enhanced biosensing applications. This was studied from an experimental and theoretical perspective: nonlinear sum-frequency components of MNP exposed to dual-frequency magnetic excitation were measured as a function of static magnetic offset field. The Langevin model in thermodynamic equilibrium was fitted to the experimental data to derive parameters of the lognormal core size distribution. These parameters were subsequently used as inputs for micromagnetic Monte-Carlo (MC)-simulations. From the hysteresis loops obtained from MC-simulations, sum-frequency components were numerically demodulated and compared with both experiment and Langevin model predictions. From the latter, we derived that approximately 90% of the frequency mixing magnetic response signal is generated by the largest 10% of MNP. We therefore suggest that small particles do not contribute to the frequency mixing signal, which is supported by MC-simulation results. Both theoretical approaches describe the experimental signal shapes well, but with notable differences between experiment and micromagnetic simulations. These deviations could result from Brownian relaxations which are, albeit experimentally inhibited, included in MC-simulation, or (yet unconsidered) cluster-effects of MNP, or inaccurately derived input for MC-simulations, because the largest particles dominate the experimental signal but concurrently do not fulfill the precondition of thermodynamic equilibrium required by Langevin theory.
KW  - Magnetic nanoparticles
KW  - Frequency mixing magnetic detection
KW  - Langevin theory
KW  - Micromagnetic simulation
KW  - Nonequilibrium dynamics
Y1  - 2021
SN  - 2079-4991
U6  - https://doi.org/10.3390/nano11051257
N1  - This article belongs to the Special Issue Applications and Properties of Magnetic Nanoparticles
VL  - 11
IS  - 5
SP  - 1
EP  - 16
PB  - MDPI
CY  - Basel
ER  -