TY - JOUR A1 - Kurz, Melanie T1 - Der Modell-Roller JF - Form : the making of design Y1 - 2006 SN - 0015-7678 VL - 2006 IS - 209 SP - 64 EP - 72 ER - TY - JOUR A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Impact of Battery Performance on the Initial Sizing of Hybrid-Electric General Aviation Aircraft JF - Journal of Aerospace Engineering N2 - Studies suggest that hybrid-electric aircraft have the potential to generate fewer emissions and be inherently quieter when compared to conventional aircraft. By operating combustion engines together with an electric propulsion system, synergistic benefits can be obtained. However, the performance of hybrid-electric aircraft is still constrained by a battery’s energy density and discharge rate. In this paper, the influence of battery performance on the gross mass for a four-seat general aviation aircraft with a hybrid-electric propulsion system is analyzed. For this design study, a high-level approach is chosen, using an innovative initial sizing methodology to determine the minimum required aircraft mass for a specific set of requirements and constraints. Only the peak-load shaving operational strategy is analyzed. Both parallel- and serial-hybrid propulsion configurations are considered for two different missions. The specific energy of the battery pack is varied from 200 to 1,000 W⋅h/kg, while the discharge time, and thus the normalized discharge rating (C-rating), is varied between 30 min (2C discharge rate) and 2 min (30C discharge rate). With the peak-load shaving operating strategy, it is desirable for hybrid-electric aircraft to use a light, low capacity battery system to boost performance. For this case, the battery’s specific power rating proved to be of much higher importance than for full electric designs, which have high capacity batteries. Discharge ratings of 20C allow a significant take-off mass reduction aircraft. The design point moves to higher wing loadings and higher levels of hybridization if batteries with advanced technology are used. Y1 - 2020 U6 - https://doi.org/10.1061/(ASCE)AS.1943-5525.0001113 SN - 1943-5525 VL - 33 IS - 3 PB - ASCE CY - Reston, Va. 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 - TY - JOUR A1 - Fabo, Sabine ED - Mohr, Klaus T1 - Sisyphus wird Steiff JF - Prädikat spießig (Boxhorn ; 21) N2 - Eine Reise durch die fremde Welt eines Kaufhaus-Schaufensters. Plüschtiere mit eingebauter Bewegungstechnik - knuffig oder nur eine Ausformulierung des Ernst des Lebens? Y1 - 2010 SN - 1864-2535 VL - 2010 SP - 58 EP - 61 PB - FH Aachen, Fachbereich Gestaltung CY - Aachen ER - TY - JOUR A1 - Laack, Walter van T1 - Nahtoderfahrungen aus medizinischer Sicht JF - Deutsche medizinische Wochenschrift : DMW N2 - Nah- versus Nachtoderfahrungen Nahtoderfahrungen (NTE) sind ein Phänomen aus der Kategorie „außergewöhnliche Bewusstseinserfahrungen“. Sie treten in unmittelbarer Nähe des eigenen Todes auf. Oft, aber nicht immer, handelt es sich dabei um Erfahrungen von Personen, die durch ärztliche Maßnahmen wiederbelebt wurden und später davon berichten (NTE-ler). Jedoch kommen solche Phänomene auch bei Menschen vor, die während einer schweren Erkrankung eine lebensbedrohliche Krise haben, hiervon aber spontan genesen. Den NTE ähnlich sind auch sogenannte Nachtod-erfahrungen sowie spontane Erlebnisse, die im Rahmen anderer außergewöhnlicher Stresssituationen auftreten. Von Nachtoderfahrungen spricht man, wenn die Betroffenen anlässlich des Todes von geliebten Angehörigen oder Freunden Erlebnisse haben, die inhaltlich ebenfalls, zumindest aber teilweise, denen von NTE entsprechen. Nachtoderfahrungen sowie spontane NTE-ähnliche Erlebnisse unterscheiden sich jedoch von den echten NTE zumeist sowohl quantitativ als auch qualitativ. Unter einem quantitativen Unterschied versteht man in diesem Zusammenhang eine in der Regel geringer ausgeprägte Komplexität, als sie sehr vielen NTE zu eigen ist. Da sich aber auch viele NTE selbst bezüglich ihrer Komplexität unterscheiden, ist der Hauptunterschied qualitativer Natur: Echte NTE besitzen gegenüber den anderen hier erwähnten Phänomenen eine größere inhaltliche und emotionale Tiefe. Sie begleiten die Betroffenen anschließend ein Leben lang – zumeist mit positiven, in Einzelfällen aber auch mit negativen Folgen, die bis zu einem späteren Suizid reichen können. Die genannten außergewöhnlichen Bewusstseinsphänomene lassen sich in ihrer Gesamtheit bei rund 5 % der Bevölkerung finden. NTE im Speziellen haben hiervon einen durchaus bedeutenden Anteil. Je nach Studie geben zwischen 18 % und 40 % aller Personen, die reanimiert wurden, an, währenddessen eine NTE erlebt zu haben. Dass nicht alle eine solche Erfahrung machen, wird von Kritikern gern dahingehend interpretiert, NTE seien rein physiologischer und keineswegs spiritueller Natur. Jedoch sollte man bedenken, dass im Fall einer rein neurophysiologischen Grundlage von NTE dann bei jedem ein solches Phänomen zu erwarten wäre, so wie beispielsweise auch die Symptome einer Hypoglykämie im Wesentlichen immer dieselben sind. Y1 - 2014 U6 - https://doi.org/10.1055/s-0034-1387363 SN - 1439-4413 (E-Journal); 0012-0472 (Print); 1437-5982 (Print) VL - Jg. 139 IS - H. 51/52 SP - 2651 EP - 2654 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Tippkötter, Nils A1 - Deterding, A. A1 - Ulber, Roland T1 - Determination of acetic acid in fermentation broth by gas-diffusion technique JF - Engineering in Life Sciences N2 - Due to the interfering effects of acetic acid in many fermentation processes, a gas-diffusion technique was developed for the online determination of acetic acid. The measurements were accomplished with a flow diffusion analysis (FDA) unit from the TRACE Analytics GmbH, Braunschweig, Germany. The diffusion analysis is based on the UV-absorbance of acetic acid at 205 nm. The measurement was achieved by the separation of an acceptor and a carrier stream (acidified fermentation broth) using a gas permeable polytetrafluoroethylene (PTFE) membrane, whereby broth constituents that would otherwise disturb the UV-measurement of acetic acid, are held back efficiently. Merely, the fermentation by-products, e.g. formic acid, is capable of diffusing through the membrane. While formic acid can disturb the measurement, carbon dioxide does not absorb at 205 nm. The method operates with time-dependent sample enrichment. During the analysis, a small volume of the acceptor stream is stopped for a defined time interval in the acceptor chamber. During this period, the gaseous acetic acid diffuses through the membrane and is enriched in the acceptor chamber. Subsequently after the enrichment, the acceptor stream flows through a UV-detector. The intensity of the signal is proportional to the acetic acid concentration. Online measurements in bioreactors via a sterile filtration probe have been accomplished. A linear calibration in the range of 0.5–5.0 g/L acetic acid with a relative standard deviation of <5 % was obtained. A sampling rate of 8 samples per hour was possible. The system was applied for the determination of acetic acid in E. coli fermentation broth. The instrument is easy to clean, very user-friendly and does not require any toxic or expensive reagents. Y1 - 2008 U6 - https://doi.org/10.1002/elsc.200820227 VL - 8 IS - 1, Special Issue: Technical Systems for the Use in Life Sciences SP - 62 EP - 67 ER - TY - JOUR A1 - Horstmann, Marie-Therese A1 - Bialonski, Stephan A1 - Noenning, Nina A1 - Mai, Heinke A1 - Prusseit, Jens A1 - Wellmer, Jörg A1 - Hinrichs, Hermann A1 - Lehnertz, Klaus T1 - State dependent properties of epileptic brain networks: Comparative graph–theoretical analyses of simultaneously recorded EEG and MEG JF - Clinical Neurophysiology N2 - Objective To investigate whether functional brain networks of epilepsy patients treated with antiepileptic medication differ from networks of healthy controls even during the seizure-free interval. Methods We applied different rules to construct binary and weighted networks from EEG and MEG data recorded under a resting-state eyes-open and eyes-closed condition from 21 epilepsy patients and 23 healthy controls. The average shortest path length and the clustering coefficient served as global statistical network characteristics. Results Independent on the behavioral condition, epileptic brains exhibited a more regular functional network structure. Similarly, the eyes-closed condition was characterized by a more regular functional network structure in both groups. The amount of network reorganization due to behavioral state changes was similar in both groups. Consistent findings could be achieved for networks derived from EEG but hardly from MEG recordings, and network construction rules had a rather strong impact on our findings. Conclusions Despite the locality of the investigated processes epileptic brain networks differ in their global characteristics from non-epileptic brain networks. Further methodological developments are necessary to improve the characterization of disturbed and normal functional networks. Significance An increased regularity and a diminished modulation capability appear characteristic of epileptic brain networks. Y1 - 2010 U6 - https://doi.org/10.1016/j.clinph.2009.10.013 SN - 1388-2457 VL - 121 IS - 2 SP - 172 EP - 185 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ferrein, Alexander A1 - Beck, Daniel A1 - Lakemeyer, Gerhard T1 - Landmark-Based Representations for Navigating Holonomic Soccer Robots / Beck, Daniel ; Ferrein, Alexander ; Lakemeyer, Gerhard JF - RoboCup 2008 : robot soccer world cup XII / Luca Iocchi ... (eds.) Y1 - 2009 SN - 978-3-642-02921-9 N1 - Lecture Notes in Computer Science ; 5399 SP - 25 EP - 36 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Heuermann, Holger A1 - Graf, W. T1 - Direkte Messung der Dispersion des Wellenwiderstandes einer Mikrostreifenleitung JF - Kleinheubacher Berichte : Vorträge und Berichte der gemeinsamen Tagung des U.R.S.I.-Landesausschusses in der Bundesrepublik Deutschland / Hrsg.: Deutsche Telekom AG. 40. 1997 (1997) Y1 - 1997 ER - TY - JOUR A1 - Fabo, Sabine ED - Könches, Barbara T1 - Welcome to the training: Actionist Respoke interaktiv by Michael Jonoschek und Rüdiger Schlömer JF - Bilder-Codes : Internationaler Medienkunstpreis 2002 Y1 - 2002 SN - 3-928201-28-X SP - 41 EP - 48 PB - ZKM CY - Karlsruhe ER - TY - JOUR A1 - Krause, Thomas T1 - Bauabrechnung und Mengenermittlung JF - Beispiele für die Baubetriebspraxis / Hoffmann, Manfred ; Kuhlmann, Willy [Hrsg.]. Y1 - 2006 SN - 978-3-8351-0002-2 N1 - Kapitel 4 SP - 49 EP - 62 PB - Teubner CY - Wiesbaden ER - TY - JOUR A1 - Bäcker, Matthias A1 - Rakowski, D. A1 - Poghossian, Arshak A1 - Biselli, Manfred A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis JF - Journal of Biotechnology N2 - A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses. Y1 - 2013 U6 - https://doi.org/10.1016/j.jbiotec.2012.03.014 SN - 0168-1656 VL - 163 IS - 4 SP - 371 EP - 376 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Combined amperometric/field-effect sensor for the detection of dissolved hydrogen JF - Sensors and actuators B: Chemical N2 - Real-time and reliable monitoring of the biogas process is crucial for a stable and efficient operation of biogas production in order to avoid digester breakdowns. The concentration of dissolved hydrogen (H₂) represents one of the key parameters for biogas process control. In this work, a one-chip integrated combined amperometric/field-effect sensor for monitoring the dissolved H₂ concentration has been developed for biogas applications. The combination of two different transducer principles might allow a more accurate and reliable measurement of dissolved H₂ as an early warning indicator of digester failures. The feasibility of the approach has been demonstrated by simultaneous amperometric/field-effect measurements of dissolved H₂ concentrations in electrolyte solutions. Both, the amperometric and the field-effect transducer show a linear response behaviour in the H₂ concentration range from 0.1 to 3% (v/v) with a slope of 198.4 ± 13.7 nA/% (v/v) and 14.9 ± 0.5 mV/% (v/v), respectively. Y1 - 2012 U6 - https://doi.org/10.1016/j.snb.2012.10.050 SN - 0925-4005 N1 - Part of special issue "Selected Papers from the 14th International Meeting on Chemical Sensors" VL - 187 SP - 168 EP - 173 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Mai, D.-T. A1 - Mourzina, Y. A1 - Schöning, Michael Josef T1 - Impedance effect of an ion-sensitive membrane: characterisation of an EMIS sensor by impedance spectroscopy, capacitance-voltage and constant-capacitance method JF - Sensors and Actuators B. 103 (2004), H. 1-2 Y1 - 2004 SN - 0925-4005 SP - 423 EP - 428 ER - TY - JOUR A1 - Heuermann, Holger A1 - Sadeghfam, Arash T1 - Electrically tunable bandpass filter with integrated carrier suppression for UHF RFID systems / Sadeghfam, Arash ; Heuermann, Holger JF - European Conference on Wireless Technology, 2008. EuWiT 2008. Y1 - 2008 SN - 978-2-87487-008-8 SP - 306 EP - 309 ER - TY - JOUR A1 - Ullrich, Sebastian A1 - Grottke, Oliver A1 - Rossaint, Rolf A1 - Staat, Manfred A1 - Deserno, Thomas M. A1 - Kuhlen, Torsten T1 - Virtual Needle Simulation with Haptics for Regional Anaesthesia Y1 - 2010 N1 - IEEE Virtual Reality 2010, Workshop on Medical Virtual Environments, Waltham, MA, USA, March 21, 2010 SP - 1 EP - 3 ER - TY - JOUR A1 - Heuermann, Holger T1 - Calibration of a Network Analyzer Without a Thru Connection for Nonlinear and Multiport Measurements JF - IEEE Transactions on Microwave Theory and Techniques. 56 (2008), H. 11, 1 Y1 - 2008 SN - 0018-9480 SP - 2505 EP - 2510 ER - TY - JOUR A1 - Laack, Walter van T1 - Neurophysiologisch ist das nicht alles zu erklären : Nahtoderfahrungen aus wissenschaftlicher Sicht JF - Der Allgemeinarzt Y1 - 2017 SN - 0172-7249 VL - 38 IS - 1 SP - 4 EP - 7 PB - Universimed Deutschland GmbH CY - Mainz ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Silicon-based field-effect devices with nanostructured surfaces for bio-/chemical sensing JF - Semiconductor micro- and nanoelectronics : Proceedings of the Seventh International Conference , Tsakhcadzor, Armenia July 3-5 2009 Y1 - 2009 SP - 51 EP - 53 ER - TY - JOUR A1 - Rau, Christoph A1 - Alexopoulos, Spiros A1 - Breitbach, Gerd A1 - Hoffschmidt, Bernhard A1 - Latzke, Markus A1 - Sattler, Johannes Christoph T1 - Transient simulation of a solar-hybrid tower power plant with open volumetric receiver at the location Barstow JF - Energy procedia : proceedings of the SolarPACES 2013 International Conference N2 - In this work the transient simulations of four hybrid solar tower power plant concepts with open-volumetric receiver technology for a location in Barstow-Daggett, USA, are presented. The open-volumetric receiver uses ambient air as heat transfer fluid and the hybridization is realized with a gas turbine. The Rankine cycle is heated by solar-heated air and/or by the gas turbine's flue gases. The plant can be operated in solar-only, hybrid parallel or combined cycle-only mode as well as in any intermediate load levels where the solar portion can vary between 0 to 100%. The simulated plant is based on the configuration of a solar-hybrid power tower project, which is in planning for a site in Northern Algeria. The meteorological data for Barstow-Daggett was taken from the software meteonorm. The solar power tower simulation tool has been developed in the simulation environment MATLAB/Simulink and is validated. Y1 - 2014 U6 - https://doi.org/10.1016/j.egypro.2014.03.157 SN - 1876-6102 VL - 49 SP - 1481 EP - 1490 PB - Elsevier CY - Amsterdam ER -