TY - CHAP A1 - Fleischhaker, Robert A1 - Gebs, Raphael A1 - Budnicki, Aleksander A1 - Wolf, M. A1 - Kleinbauer, Jochen A1 - Sutter, Dirk H. T1 - Compact gigawatt-class sub-picosecond Yb:YAG thin-disk regenerative chirped-pulse amplifier with high average power at up to 800 kHz T2 - Lasers and electro-optics europe (CLEO EUROPE/IQEC) : International quantum electronics conference : 12 - 16 May 2013, Munich, GE. Y1 - 2013 SN - 978-1-4799-0593-5 U6 - http://dx.doi.org/10.1109/CLEOE-IQEC.2013.6801054 N1 - Lasers and Electro-Optics Europe (CLEO EUROPE/IQEC) <5, 2013, Munich, GE> PB - IEEE Computer Society ER - TY - JOUR A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Comparative assessment of parallel-hybrid-electric propulsion systems for four different aircraft JF - Journal of Aircraft N2 - Until electric energy storage systems are ready to allow fully electric aircraft, the combination of combustion engine and electric motor as a hybrid-electric propulsion system seems to be a promising intermediate solution. Consequently, the design space for future aircraft is expanded considerably, as serial hybrid-electric, parallel hybrid-electric, fully electric, and conventional propulsion systems must all be considered. While the best propulsion system depends on a multitude of requirements and considerations, trends can be observed for certain types of aircraft and certain types of missions. This Paper provides insight into some factors that drive a new design toward either conventional or hybrid propulsion systems. General aviation aircraft, regional transport aircraft vertical takeoff and landing air taxis, and unmanned aerial vehicles are chosen as case studies. Typical missions for each class are considered, and the aircraft are analyzed regarding their takeoff mass and primary energy consumption. For these case studies, a high-level approach is chosen, using an initial sizing methodology. Only parallel-hybrid-electric powertrains are taken into account. Aeropropulsive interaction effects are neglected. Results indicate that hybrid-electric propulsion systems should be considered if the propulsion system is sized by short-duration power constraints. However, if the propulsion system is sized by a continuous power requirement, hybrid-electric systems offer hardly any benefit. Y1 - 2020 U6 - http://dx.doi.org/10.2514/1.C035897 SN - 1533-3868 VL - 57 IS - 5 PB - AIAA CY - Reston, Va. ER - TY - CHAP A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Comparative assessment of parallel-hybrid-electric propulsion systems for four different aircraft T2 - AIAA SciTech Forum 2020, 06.01.2020 - 10.01.2020, Orlando Y1 - 2020 U6 - http://dx.doi.org/10.2514/6.2020-1502 ER - TY - JOUR A1 - Hoffschmidt, Bernhard A1 - Fend, Thomas A1 - Jorgensen, Gary A1 - Küster, Harald T1 - Comparative assessment of solar concentrator materials / Fend, Thomas ; Hoffschmidt, Bernhard ; Jorgensen, Gary ; Küster, Harald ; Krüger, Dirk ; Pitz-Paal, Robert ; Riebrock, Peter ; Riffelmann, Klaus-Jürgen JF - Solar energy. 74 (2003), H. 2 Y1 - 2003 SN - 0038-092X SP - 149 EP - 155 ER - TY - JOUR A1 - Hoffschmidt, Bernhard A1 - Fend, Thomas A1 - Jorgensen, Gary T1 - Comparative assessment of solar concentrator materials / Thomas Fend ; Bernhard Hoffschmidt ; Gary Jorgensen ... JF - Renewable energy for local communities of Europe : (toward Rio+10) ; proceedings / EuroSun 2002, the 4th ISES Europe Solar Congress ; Bologna (Italy), 23 - 26 June 2002 / ISES Italia Y1 - 2002 SN - 88-900893-0-X N1 - Eurosun <4, 2002, Bologna> ; International Solar Energy Society SP - paper_125.pdf CY - Bologna ER - TY - JOUR A1 - Förster, Arnold A1 - Hardtdegen, Hilde A1 - Ungermanns, C. T1 - Comparative investigation of electrical and optical characteristics of AlxGa1-xAs/GaAs structures deposited by LP-MOVPE and MBE / H. Hardtdegen ; M. Hollfelder ; C. Ungermanns ... A. Förster ... JF - Compound semiconductors, 1994 : proceedings of the twenty-first International Symposium on Compound Semiconductors held in San Diego, California, 18 - 22 September, 1994 / ed. by Herb Goronkin ... - (Conference series / Institute of Physics ; 141) Y1 - 1995 SN - 0-7503-0226-7 N1 - International Symposium on Compound Semiconductors <21, 1994, San Diego, Calif.> ; Institute of Physics SP - 81 EP - ff. PB - Institute of Physics CY - Bristol [u.a.] ER - TY - JOUR A1 - Rupp, Matthias A1 - Schulze, Sven A1 - Kuperjans, Isabel T1 - Comparative life cycle analysis of conventional and hybrid heavy-duty trucks JF - World electric vehicle journal N2 - Heavy-duty trucks are one of the main contributors to greenhouse gas emissions in German traffic. Drivetrain electrification is an option to reduce tailpipe emissions by increasing energy conversion efficiency. To evaluate the vehicle’s environmental impacts, it is necessary to consider the entire life cycle. In addition to the daily use, it is also necessary to include the impact of production and disposal. This study presents the comparative life cycle analysis of a parallel hybrid and a conventional heavy-duty truck in long-haul operation. Assuming a uniform vehicle glider, only the differing parts of both drivetrains are taken into account to calculate the environmental burdens of the production. The use phase is modeled by a backward simulation in MATLAB/Simulink considering a characteristic driving cycle. A break-even analysis is conducted to show at what mileage the larger CO2eq emissions due to the production of the electric drivetrain are compensated. The effect of parameter variation on the break-even mileage is investigated by a sensitivity analysis. The results of this analysis show the difference in CO2eq/t km is negative, indicating that the hybrid vehicle releases 4.34 g CO2eq/t km over a lifetime fewer emissions compared to the diesel truck. The break-even analysis also emphasizes the advantages of the electrified drivetrain, compensating the larger emissions generated during production after already a distance of 15,800 km (approx. 1.5 months of operation time). The intersection coordinates, distance, and CO2eq, strongly depend on fuel, emissions for battery production and the driving profile, which lead to nearly all parameter variations showing an increase in break-even distance. Y1 - 2018 U6 - http://dx.doi.org/10.3390/wevj9020033 SN - 2032-6653 VL - 9 IS - 2 SP - Article No. 33 PB - MDPI CY - Basel 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 - http://dx.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 - TY - CHAP A1 - Finger, Felix T1 - Comparative Performance and Benefit Assessment of VTOL and CTOL UAVs T2 - Deutscher Luft- und Raumfahrtkongress (DLRK) 2016, 13.-15.9.2016 Y1 - 2016 ER - TY - JOUR A1 - Schubert, Nicole A1 - Scholl, Ingrid T1 - Comparing GPU-based multi-volume ray casting techniques JF - Computer Science - Research and Development Y1 - 2011 SN - 1865-2042 VL - 26 IS - 12 SP - 39 EP - 50 PB - Springer CY - Berlin ER -