TY - JOUR A1 - Warerkar, Shashikant A1 - Schmitz, Stefan A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Reißel, Martin A1 - Tamme, Rainer T1 - Air-Sand Heat Exchanger for High-Temperature Storage JF - Journal of Solar Energy Engineering. 133 (2011), H. 2 Y1 - 2011 SN - 0199-6231 N1 - 7 pages SP - 021010 PB - ASME CY - New York ER - TY - JOUR A1 - Doorschodt, B. M. A1 - Schreinemachers, M. C. J. M. A1 - Behbahani, Mehdi A1 - Florquin, S. A1 - Weis, J. A1 - Staat, Manfred A1 - Tolba, R. H. T1 - Hypothermic machine perfusion of kidney grafts: which pressure is preferred JF - Annals of Biomedical Engineering. 39 (2011), H. 3 Y1 - 2011 SN - 1573-9686 SP - 1051 EP - 1059 PB - Springer CY - Berlin ER - TY - CHAP A1 - Ohndorf, Andreas A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang A1 - Schartner, Karl-Heinz T1 - Flight times to the heliopause using a combination of solar and radioisotope electric propulsion T2 - 32nd International Electric Propulsion Conference N2 - We investigate the interplanetary flight of a low-thrust space probe to the heliopause,located at a distance of about 200 AU from the Sun. Our goal was to reach this distance within the 25 years postulated by ESA for such a mission (which is less ambitious than the 15-year goal set by NASA). Contrary to solar sail concepts and combinations of allistic and electrically propelled flight legs, we have investigated whether the set flight time limit could also be kept with a combination of solar-electric propulsion and a second, RTG-powered upper stage. The used ion engine type was the RIT-22 for the first stage and the RIT-10 for the second stage. Trajectory optimization was carried out with the low-thrust optimization program InTrance, which implements the method of Evolutionary Neurocontrol,using Artificial Neural Networks for spacecraft steering and Evolutionary Algorithms to optimize the Neural Networks’ parameter set. Based on a parameter space study, in which the number of thrust units, the unit’s specific impulse, and the relative size of the solar power generator were varied, we have chosen one configuration as reference. The transfer time of this reference configuration was 29.6 years and the fastest one, which is technically more challenging, still required 28.3 years. As all flight times of this parameter study were longer than 25 years, we further shortened the transfer time by applying a launcher-provided hyperbolic excess energy up to 49 km2/s2. The resulting minimal flight time for the reference configuration was then 27.8 years. The following, more precise optimization to a launch with the European Ariane 5 ECA rocket reduced the transfer time to 27.5 years. This is the fastest mission design of our study that is flexible enough to allow a launch every year. The inclusion of a fly-by at Jupiter finally resulted in a flight time of 23.8 years,which is below the set transfer-time limit. However, compared to the 27.5-year transfer,this mission design has a significantly reduced launch window and mission flexibility if the escape direction is restricted to the heliosphere’s “nose". KW - low-thrust trajectory optimization KW - heliosphere KW - ion propulsion Y1 - 2011 N1 - IEPC-2011-051 32nd International Electric Propulsion Conference,September 11–15, 2011 Wiesbaden, Germany SP - 1 EP - 12 ER - TY - CHAP A1 - Baumann, Torsten A1 - Teixeira Boura, Cristiano José A1 - Eckstein, Julian A1 - Felinks, Jan A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Schmitz, Stefan A1 - Zunft, Stefan T1 - Air-sand heat exchanger T2 - 6th International Renewable Energy Storage Conference (IRES 2011) : November 28 - 30, 2011, bcc Berlin Congress Center, Berlin, Germany / EUROSOLAR ... Y1 - 2011 PB - Eurosolar CY - Bonn ER - TY - JOUR A1 - Scholz, Christina A1 - Romagnoli, Daniele A1 - Dachwald, Bernd A1 - Theil, Stephan T1 - Performance analysis of an attitude control system for solar sails using sliding masses JF - Advances in Space Research Y1 - 2011 SN - 0273-1177 VL - 48 IS - 11 SP - 1822 EP - 1835 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Baumann, Torsten A1 - Teixeira Boura, Cristiano José A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Schmitz, Stefan A1 - Zunft, Stefan T1 - Air-sand heat exchanger: materials and flow properties T2 - SolarPACES 2011 : concentrating solar power and chemical energy systems : 20 - 23 September, 2011, Granada, Spain Y1 - 2011 CY - Granada ER - TY - CHAP A1 - Fricke, Barbara A1 - Ziolko, C. A1 - Anthrakidis, Anette A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard A1 - Dillig, M. A1 - Giese, F. T1 - InnoSol - life cycle analysis of solar power tower plants T2 - SolarPACES 2011 : concentrating solar power and chemical energy systems : 20 - 23 September, 2011, Granada, Spain Y1 - 2011 CY - Granada ER - TY - JOUR A1 - Levers, A. A1 - Staat, Manfred A1 - Laack, Walter van T1 - Analyse der Langzeitwirkung der MBST® KernspinResonanzTherapie bei Gonarthrose T1 - Analysis of the Long-term Effect of the MBST® Nuclear Magnetic Resonance Therapy on Gonarthrosis N2 - Originalausgabe: Orthopädische Praxis Jg. 47. 2011 H. 11; S. 536-543. Mit freundlicher Genehmigung des Verlags Zusammenfassung: Auf der Basis von Patientenabfragen mittels Fragebogen zum Schmerzempfinden und zur Einschränkung bei Aktivitäten des alltäglichen Lebens wird die Langzeitwirkung der MBST® KernspinResonanz-Therapie bei Gonarthrose untersucht. An der Studie nahmen 39 Patienten teil, bei denen die Therapie bis zu vier Jahre zurückliegt. Neben einer Gesamtbetrachtung wird der Erfolg auch in Abhängigkeit von Alter, Geschlecht und sportlicher Aktivität analysiert. Insgesamt weist die Studie auf eine anhaltende Verbesserung des Gesundheitszustands mit zum Teil deutlicher Schmerzlinderung auch noch nach vier Jahren hin, jedoch mit einer leichten Schmerzzunahme gegen Ende des Untersuchungszeitraums von vier Jahren. Eine tendenziell positivere Wirkung bei Frauen, älteren Menschen oder auch sportlich nicht-aktiven Patienten lässt auf eine mögliche Beeinflussung des Erfolgs der Therapie durch (Über-)Belastung im Alltag schließen. Ein zusätzlich positiver Effekt der Therapie auf die Knochendichte ist ebenfalls denkbar, dies bleibt jedoch offen. N2 - Original edition: Orthopädische Praxis Vol. 47. 2011 Issue 11; P. 536-543. On the friendly authority of the publisher. Abstract: Based upon a questionnaire for patient-queries regarding pain-sensation and activity-restrictions during everyday task, the long-term effect of MBST® nuclear magnetic resonance therapy is studied in osteoarthritis of the knee. 39 patients, whose therapy dates back up to four years, participated in the study. In addition to an overall view, the success of this therapy is also analyzed regarding age, gender and physical activities. Overall, the study pointed out a sustained improvement in the patients´ local health-status with a significant pain-relief even after four years, but also with a slight increase in pain towards the end of that four-year period. There tends to be more positive effect on women, on elderly of also on even non-sports-active patients which suggest a possible influence by daily (over)-stressing on the success of the therapy. An additional positive effect of the therapy on bone density is also conceivable, however, this remains open. KW - Kniegelenkarthrose KW - Gonarthrose KW - MBST KW - Arthosetherapie KW - gonarthrosis KW - MBST KW - arthrosis therapy Y1 - 2011 ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Novacek, V. A1 - Tolba, R. A1 - Klinge, U. A1 - Turquier, F. A1 - Staat, Manfred T1 - Experimental and Computational approach to study colorectal anastomosis. ISB2011, Proceedings of the XXIII Congress of the International Society of Biomechanics, Brussels, Belgium, July 3-7, 2011 N2 - Summary: This paper presents a methodology to study and understand the mechanics of stapled anastomotic behaviors by combining empirical experimentation and finite element analysis. Performance of stapled anastomosis is studied in terms of leakage and numerical results which are compared to in vitro experiments performed on fresh porcine tissue. Results suggest that leaks occur between the tissue and staple legs penetrating through the tissue. KW - Anastomose KW - Finite-Elemente-Methode KW - Biomechanik KW - Anastomosis KW - Finite element method KW - Biomechanics Y1 - 2011 ER - TY - JOUR A1 - Kleefeld, Andreas A1 - Reißel, Martin T1 - The Levenberg–Marquardt method applied to a parameter estimation problem arising from electrical resistivity tomography JF - Applied Mathematics and Computation Y1 - 2011 SN - 0096-3003 VL - 217 IS - 9 SP - 4490 EP - 4501 PB - Elsevier CY - Amsterdam ER -