TY - CHAP A1 - Staat, Manfred A1 - Heitzer, Michael ED - Staat, Manfred ED - Heitzer, Michael T1 - Probabilistic limit and shakedown problems T2 - Numerical methods for limit and shakedown analysis. Deterministic and probabilistic problems Y1 - 2003 SN - 3-00-010001-6 N1 - NIC Series VL - 15 SP - 217 EP - 268 PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - BOOK A1 - Staat, Manfred A1 - Heitzer, Michael T1 - Numerical methods for limit and shakedown analysis. Deterministic and probabilistic problems. Y1 - 2003 SN - 3-00-010001-6 N1 - NIC Series Vol. 15 / Ed. by Staat, M; Heitzer, M. PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - CHAP A1 - Seboldt, Wolfgang A1 - Dachwald, Bernd T1 - Solar sails for near-term advanced scientific deep space missions T2 - Proceedings of the 8th International Workshop on Combustion and Propulsion N2 - Solar sails are propelled in space by reflecting solar photons off large mirroring surfaces, thereby transforming the momentum of the photons into a propulsive force. This innovative concept for low-thrust space propulsion works without any propellant and thus provides a wide range of opportunities for highenergy low-cost missions. Offering an efficient way of propulsion, solar sailcraft could close a gap in transportation options for highly demanding exploration missions within our solar system and even beyond. On December 17th, 1999, a significant step was made towards the realization of this technology: a lightweight solar sail structure with an area of 20 m × 20 m was successfully deployed on ground in a large facility at the German Aerospace Center (DLR) at Cologne. The deployment from a package of 60 cm × 60 cm × 65 cm with a total mass of less than 35 kg was achieved using four extremely light-weight carbon fiber reinforced plastics (CFRP) booms with a specific mass of 100 g/m. The paper briefly reviews the basic principles of solar sails as well as the technical concept and its realization in the ground demonstration experiment, performed in close cooperation between DLR and ESA. Next possible steps are outlined. They could comprise the in-orbit demonstration of the sail deployment on the upper stage of a low-cost rocket and the verification of the propulsion concept by an autonomous and free flying solar sail in the frame of a scientific mission. It is expected that the present design could be extended to sail sizes of about (40 m)2 up to even (70 m)2 without significant mass penalty. With these areas, the maximum achievable thrust at 1 AU would range between 10 and 40 mN – comparable to some electric thrusters. Such prototype sails with a mass between 50 and 150 kg plus a micro-spacecraft of 50 to 250 kg would have a maximum acceleration in the order of 0.1 mm/s2 at 1 AU, corresponding to a maximum ∆V-capability of about 3 km/s per year. Two near/medium-term mission examples to a near-Earth asteroid (NEA) will be discussed: a rendezvous mission and a sample return mission. KW - solar sail KW - low-thrust KW - near-Earth asteroid KW - sample return KW - solar system Y1 - 2003 N1 - Proceedings of the 8th International Workshop on Combustion and Propulsion. Pozzuoli, Italy, 16 - 21 June 2002. ER - TY - JOUR A1 - Staat, Manfred T1 - Some Achievements of the European Project LISA for FEM Based Limit and Shakedown Analysis JF - Computational mechanics : developments and applications, 2002 : presented at the 2002 ASME Pressure Vessels and Piping Conference, Vancouver, British Columbia, Canada, August 5 - 9. / Badie, N. [ed] Y1 - 2002 SN - 0791846520 N1 - Serie PVP ; vol. 441. SP - 177 EP - 185 PB - American Society of Mechanical Engineers CY - New York ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Limit and Shakedown Analysis with Uncertain Data JF - Stochastic optimization techniques : numerical methods and technical applications / Marti, K. [ed] Y1 - 2002 SN - 3-540-42889-5 SP - 241 EP - 254 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Sponagel, Stefan A1 - Baroud, G. A1 - Steffen, T. A1 - Wu, J. T1 - Parameter identification for cement infiltration of osteoporotic bone JF - Poromechanics II : Proceedings of the Second Biot Conference on Poromechanics Grenoble, France 26 - 28 August 2002 / ed. by J.-L. Auriault ... Y1 - 2002 SN - 90-5809-394-8 SP - 55 EP - 58 PB - Balkema CY - Lisse [u.a.] ER - TY - JOUR A1 - Artmann, Gerhard A1 - Trzewik, Jürgen A1 - Ates, M. T1 - A novel method to quantify mechanical tension in cell monolayers. Trzewik, Jürgen; Ates, M., Artmann, Gerhard Michael JF - Biomedizinische Technik. 47 (2002), H. Suppl. 1. Pt. 1 Y1 - 2002 SN - 0013-5585 N1 - Druckausgabe unter 63 Z 47 vorhanden SP - 379 EP - 381 ER - TY - JOUR A1 - Maggakis-Kelemen, Christina A1 - Biselli, Manfred A1 - Artmann, Gerhard T1 - Determination of the elastic shear modulus of cultured human red blood cells JF - Biomedizinische Technik. 47 (2002), H. Suppl. 1 Pt. 1 Y1 - 2002 SN - 0013-5585 N1 - Druckausgabe unter 63 Z 471 vorhanden SP - 106 EP - 109 ER - TY - JOUR A1 - Artmann, Gerhard A1 - Zhou-Stache, J. A1 - Buettner, R. A1 - Mittermayer, C. [u.a.] T1 - Inhibition of TNF-alpha induced cell death in HUVEC and Jurkat cells by protocatechuic acid. Zhou-Stache, J.; Buettner, R.; Artmann, Gerhard Michael; Mittermayer, C.; Bosserhoff, A. K. JF - Medical and Biological Engineering and Computing. 40 (2002), H. 6 Y1 - 2002 SN - 0140-0118 SP - 698 EP - 703 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Yalcin, Ozlem A1 - Resmi, Halil A1 - Baskurt, Oguz K. T1 - Can white blood cell activation be one of the major factors that affect hemorheological parameters during and after exercise? JF - Clinical Hemorheology and Microcirculation. 26 (2002), H. 3 Y1 - 2002 SN - 1386-0291 N1 - = The 11th European Symposium on Clinical Hemorheology, Rouen, France, 19-22 September 2000 SP - 189 EP - 193 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. T1 - Optimization of Interplanetary Rendezvous Trajectories for Solar Sailcraft Using a Neurocontroller JF - A collection of technical papers / AIAA Astrodynamics Specialist Conference : Monterey, California, 5 - 8 August 2002. - Vol. 2 Y1 - 2002 SN - 1-56347-549-9 N1 - Astrodynamics Specialist Conference <2002, Monterey, Calif.> American Institute of Aeronautics and Astronautics ; AIAA paper number: AIAA-2002-4989 SP - 1263 EP - 1270 PB - American Institute of Aeronautics and Astronautics CY - Reston, Va. ER - TY - CHAP A1 - Staat, Manfred A1 - Heitzer, Michael T1 - The restricted influence of kinematic hardening on shakedown loads N2 - Structural design analyses are conducted with the aim of verifying the exclusion of ratcheting. To this end it is important to make a clear distinction between the shakedown range and the ratcheting range. In cyclic plasticity more sophisticated hardening models have been suggested in order to model the strain evolution observed in ratcheting experiments. The hardening models used in shakedown analysis are comparatively simple. It is shown that shakedown analysis can make quite stable predictions of admissible load ranges despite the simplicity of the underlying hardening models. A linear and a nonlinear kinematic hardening model of two-surface plasticity are compared in material shakedown analysis. Both give identical or similar shakedown ranges. Structural shakedown analyses show that the loading may have a more pronounced effect than the hardening model. KW - Biomedizinische Technik KW - Einspielen KW - Shakedown KW - Ratcheting KW - Bruchmechanik KW - shakedown KW - material shakedown KW - linear kinematic hardening KW - nonlinear kinematic hardening KW - ratchetting Y1 - 2002 ER - TY - CHAP A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang A1 - Häusler, Bernd T1 - Performance requirements for near-term interplanetary solar sailcraft missions T2 - 6th International AAAF Symposium on Space Propulsion: Propulsion for Space Transportation of the XXIst Century N2 - Solar sailcraft provide a wide range of opportunities for high-energy low-cost missions. To date, most mission studies require a rather demanding performance that will not be realized by solar sailcraft of the first generation. However, even with solar sailcraft of moderate performance, scientifically relevant missions are feasible. This is demonstrated with a Near Earth Asteroid sample return mission and various planetary rendezvous missions. Y1 - 2002 N1 - 6th International AAAF Symposium on Space Propulsion: Propulsion for Space Transportation of the XXIst Century, Versailles, France, 14-16 May 2002 ER -