TY - CHAP A1 - Staat, Manfred T1 - Problems and chances for probabilistic fracture mechanics in the analysis of steel pressure boundary reliability. - Überarb. Ausg. N2 - In: Technical feasibility and reliability of passive safety systems for nuclear power plants. Proceedings of an Advisory Group Meeting held in Jülich, 21-24 November 1994. - Vienna , 1996. - Seite: 43 - 55 IAEA-TECDOC-920 Abstract: It is shown that the difficulty for probabilistic fracture mechanics (PFM) is the general problem of the high reliability of a small population. There is no way around the problem as yet. Therefore what PFM can contribute to the reliability of steel pressure boundaries is demon­strated with the example of a typical reactor pressure vessel and critically discussed. Although no method is distinguishable that could give exact failure probabilities, PFM has several addi­tional chances. Upper limits for failure probability may be obtained together with trends for design and operating conditions. Further, PFM can identify the most sensitive parameters, improved control of which would increase reliability. Thus PFM should play a vital role in the analysis of steel pressure boundaries despite all shortcomings. KW - Bruchmechanik KW - probabilistic fracture mechanics KW - PFM Y1 - 2006 ER - TY - JOUR A1 - Albracht, Kirsten A1 - Arampatzis, Adamantios T1 - Influence of the mechanical properties of the muscle-tendon unit on force generation in runners with different running economy JF - Biological Cybernetics Y1 - 2006 U6 - https://doi.org/10.1007/s00422-006-0070-z SN - 1432-0770 VL - 95 IS - 1 SP - 87 EP - 96 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Kahle, Ralph A1 - Wie, Bong T1 - Solar Sailing Kinetic Energy Impactor (KEI) Mission Design Tradeoffs for Impacting and Deflecting Asteroid 99942 Apophis JF - AIAA Guidance, Navigation, and Control Conference & Exhibit - AIAA Atmospheric Flight Mechanics Conference & Exhibit - AIAA Modeling and Simulation Technologies Conference & Exhibit - AIAA/AAS Astrodynamics Specialist Conference & Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 ) Y1 - 2006 SN - 1-56347-802-1 N1 - American Institute of Aeronautics and Astronautics ; American Astronautical Society ; AIAA/AAS Astrodynamics Specialist Conference & Exhibit <2006, Keystone, Colo.> ; AIAA paper number: AIAA-2006-6178 SP - 1 EP - 20 PB - American Institute of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mengali, Giovanni A1 - Quarta, Alessandrao A. A1 - Macdonald, Malcolm T1 - Parametric Model and Optimal Control of Solar Sails with Optical Degradation JF - Journal of guidance, control, and dynamics. 29 (2006), H. 5 Y1 - 2006 SN - 0162-3192 N1 - 2. ISSN: 0731-5090 SP - 1170 EP - 1178 ER - TY - CHAP A1 - Loeb, Horst W. A1 - Schartner, Karl-Heinz A1 - Seboldt, Wolfgang A1 - Dachwald, Bernd A1 - Streppel, Joern A1 - Meusemann, Hans A1 - Schülke, Peter T1 - SEP for a lander mission to the jovian moon europa T2 - 57th International Astronautical Congress N2 - Under DLR-contract, Giessen University and DLR Cologne are studying solar-electric propulsion missions (SEP) to the outer regions of the solar system. The most challenging reference mission concerns the transport of a 1.35-tons chemical lander spacecraft into an 80-RJ circular orbit around Jupiter, which would enable to place a 375 kg lander with 50 kg of scientific instruments on the surface of the icy moon "Europa". Thorough analyses show that the best solution in terms of SEP launch mass times thrusting time would be a two-stage EP module and a triple-junction solar array with concentrators which would be deployed step by step. Mission performance optimizations suggest to propel the spacecraft in the first EP stage by 6 gridded ion thrusters, running at 4.0 kV of beam voltage, which would save launch mass, and in the second stage by 4 thrusters with 1.25 to 1.5 kV of positive high voltage saving thrusting time. In this way, the launch mass of the spacecraft would be kept within 5.3 tons. Without a launcher's C3 and interplanetary gravity assists, Jupiter might be reached within about 4 yrs. The spiraling-down into the parking orbit would need another 1.8 yrs. This "large mission" can be scaled down to a smaller one, e.g., by halving all masses, the solar array power, and the number of thrusters. Due to their reliability, long lifetime and easy control, RIT-22 engines have been chosen for mission analysis. Based on precise tests, the thruster performance has been modeled. Y1 - 2006 U6 - https://doi.org/10.2514/6.IAC-06-C4.4.04 N1 - 57th International Astronautical Congress, 02 October 2006 - 06 October 2006, Valencia, Spain. SP - 1 EP - 12 ER - TY - GEN A1 - Staat, Manfred A1 - Barry, Steve T1 - Continuum Mechanics with an Introduction to the Finite Element Method / Steve Barry; Manfred Staat. With extensions by Manfred Staat. N2 - Contents: 1 Introduction 2 One Dimensional Continuum Mechanics 3 Tensors 4 Three Dimensional Stress and Strain 5 Conservation Laws 6 Contiunuum Modelling 7 Plain Problems 8 Questions 9 Reference Information KW - Technische Mechanik KW - Finite-Elemente-Methode Y1 - 2006 ER - TY - JOUR A1 - Digel, Ilya A1 - Maggakis-Kelemen, Christina A1 - Zerlin, Kay A1 - Linder, Peter T1 - Body temperature-related structural transitions of monotremal and human hemoglobin JF - Biophysical Journal. 91 (2006), H. 8 Y1 - 2006 SN - 1542-0086 SP - 3014 EP - 3021 ER - TY - JOUR A1 - Kotliar, Konstantin A1 - Koshitz, I. N. A1 - Svetlowa, O. V. A1 - Makarov, F. N. T1 - Biomechanical analysis of traditional and contemporary conceptions on pathogenesis of the primary open angle glaucoma / Koshitz, I. N. ; Svetlova, O. V. ; Kotliar, K. E. ; Makarov, F. N. ; Smolnikov, B. A. JF - Glaukoma (2005) Y1 - 2005 N1 - Original in Russisch SP - 41 EP - 63 PB - - ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Kayatekin, Muammer B. A1 - Uysal, N. A1 - Resmi, H. T1 - Does antioxidant supplementation alter the effects of acute exercise on erythrocyte aggregation, deformability and endothelium adhesion in untrained rats? Kayatekin, Muammer B.; Uysal N.; Resmi, H.; Bediz, Seref C.; Temiz Artmann, A.; Genç, S.; Tugyan, K. JF - International Journal for Vitamin and Nutrition Research. 75 (2005), H. 4 Y1 - 2005 SN - 0300-9831 SP - 243 EP - 250 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Resmi, Halil A1 - Akhunlar, Hülya A1 - Güner, Gül T1 - In vitro effects of high glucose concentrations on membrane protein sulfhydryl oxidation, G-actin and deformability of human erythrocytes. Resmi, Halil ; Akhunlar, Hülya ; Temiz Artmann, Aysegül ; Güner, Gül JF - Cell biochemistry and function. 23 (2005), H. 3 Y1 - 2005 SN - 0263-6484 SP - 163 EP - 168 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Akhisaroglu, M. A1 - Sercan, Z. A1 - Kayatekin, B. M. T1 - Adhesion of Erythrocytes to Endothelial Cells After Acute Exercise: Differences in Red Blood Cells from Juvenile and Adult Rats. Temiz Artmann, A.; Akhisaroglu, M.; Sercan, Z.; Kayatekin, BM.; Yorukoglu, K.; Kirkali, G. JF - Physiological Research (2005) Y1 - 2005 SN - 0862-8408 N1 - pre-press article ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Saklamaz, Ali A1 - Comlekci, Abdurrahman A1 - Caliskan, Sezer T1 - The beneficial effects of lipid-lowering drugs beyond lipid-lowering effects: A comparative study with pravastatin, atorvastatin, and fenofibrate in patients with type IIa and type IIb hyperlipidemia / Saklamaz, Ali ; Comlekci, Abdurrahman ; Temiz, Aysegu JF - Metabolism. 54 (2005), H. 5 Y1 - 2005 SN - 0026-0495 SP - 677 EP - 681 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ohndorf, A. A1 - Seboldt, Wolfgang T1 - Optimierung der Lageregelung von Raumfahrzeugen mit Niedrigschubantrieb mittels evolutionärer neuronaler Regler / A. Ohndorf ; B. Dachwald ; W. Seboldt JF - Deutscher Luft- und Raumfahrtkongress 2005 : Friedrichshafen, 26. bis 29. September 2005, Motto: Luft- und Raumfahrt - Grenzen überwinden, Horizonte erweitern / Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V. (DGLR). [Red.: Peter Brandt (verantwortlich)]. Bd. 3. - (Jahrbuch ... der Deutschen Gesellschaft für Luft- und Raumfahrt Y1 - 2005 N1 - Deutscher Luft- und Raumfahrt-Kongress <2005, Friedrichshafen> ; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth ; Dokumentnr: DGLR-2005-224 SP - 1971 EP - 1978 PB - DGLR CY - Bonn ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - Multiple Near-Earth Asteroid Rendezvous and Sample Return Using First Generation Solar Sailcraft JF - Acta Astronautica. 57 (2005), H. 11 Y1 - 2005 SN - 0094-5765 SP - 864 EP - 875 ER - TY - JOUR A1 - Staat, Manfred T1 - Local and global collapse pressure of longitudinally flawed pipes and cylindrical vessels JF - International Journal of Pressure Vessels and Piping. 82 (2005), H. 3 Y1 - 2005 SN - 0308-0161 SP - 217 EP - 225 ER - TY - JOUR A1 - Staat, Manfred T1 - Local and global collapse pressure of longitudinally flawed pipes and cylindrical vessels N2 - Limit loads can be calculated with the finite element method (FEM) for any component, defect geometry, and loading. FEM suggests that published long crack limit formulae for axial defects under-estimate the burst pressure for internal surface defects in thick pipes while limit loads are not conservative for deep cracks and for pressure loaded crack-faces. Very deep cracks have a residual strength, which is modelled by a global collapse load. These observations are combined to derive new analytical local and global collapse loads. The global collapse loads are close to FEM limit analyses for all crack dimensions. KW - Finite-Elemente-Methode KW - Grenzwertberechnung KW - Axialbelastung KW - FEM KW - Grenzwertberechnung KW - Axialbelastung KW - Traglastanalyse KW - Limit analysis KW - Global and local collapse KW - Axially cracked pipe KW - Pressure loaded crack-face Y1 - 2005 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimization of very-low-thrust trajectories using evolutionary neurocontrol JF - Acta Astronautica N2 - Searching optimal interplanetary trajectories for low-thrust spacecraft is usually a difficult and time-consuming task that involves much experience and expert knowledge in astrodynamics and optimal control theory. This is because the convergence behavior of traditional local optimizers, which are based on numerical optimal control methods, depends on an adequate initial guess, which is often hard to find, especially for very-low-thrust trajectories that necessitate many revolutions around the sun. The obtained solutions are typically close to the initial guess that is rarely close to the (unknown) global optimum. Within this paper, trajectory optimization problems are attacked from the perspective of artificial intelligence and machine learning. Inspired by natural archetypes, a smart global method for low-thrust trajectory optimization is proposed that fuses artificial neural networks and evolutionary algorithms into so-called evolutionary neurocontrollers. This novel method runs without an initial guess and does not require the attendance of an expert in astrodynamics and optimal control theory. This paper details how evolutionary neurocontrol works and how it could be implemented. The performance of the method is assessed for three different interplanetary missions with a thrust to mass ratio <0.15mN/kg (solar sail and nuclear electric). Y1 - 2005 SN - 1879-2030 VL - 57 IS - 2-8 SP - 175 EP - 185 PB - Elsevier CY - Amsterdam [u.a.] ER - TY - JOUR A1 - Staat, Manfred T1 - Direct finite element route for design-by-analysis of pressure components N2 - In the new European standard for unfired pressure vessels, EN 13445-3, there are two approaches for carrying out a Design-by-Analysis that cover both the stress categorization method (Annex C) and the direct route method (Annex B) for a check against global plastic deformation and against progressive plastic deformation. This paper presents the direct route in the language of limit and shakedown analysis. This approach leads to an optimization problem. Its solution with Finite Element Analysis is demonstrated for mechanical and thermal actions. One observation from the examples is that the so-called 3f (3Sm) criterion fails to be a reliable check against progressive plastic deformation. Precise conditions are given, which greatly restrict the applicability of the 3f criterion. KW - Einspielen KW - Plastizität KW - Deformation KW - Analytischer Zulaessigkeitsnachweis KW - Einspiel-Analyse KW - fortschreitende plastische Deformation KW - alternierend Verformbarkeit KW - Einspiel-Kriterium KW - Design-by-analysis KW - Shakedown analysis KW - Progressive plastic deformation KW - Alternating plasticity KW - Shakedown criterion Y1 - 2005 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Turyshev, Slava G. A1 - Dittus, H. A1 - Shao, M. [u.a.] T1 - Fundamental Physics with the Laser Astrometric Test Of Relativity / S.G. Turyshev ; H. Dittus ; M. Shao ... B.Dachwald ... JF - Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588) Y1 - 2005 SN - 9290928999 N1 - ISBN der CD-ROM-Ausg.: 9290928999 ; Symposium Trends in Space Science and Cosmic Vision 2020 <2005, Noordwijk> ; ESLAB symposium <39, 2005, Noordwijk> ; European Space Laboratory SP - 8 EP - 11 PB - ESA Publ. Div. CY - Noordwijk ER - TY - JOUR A1 - Dittus, H. A1 - Turyshev, S. G. A1 - Dachwald, Bernd A1 - Blome, Hans-Joachim T1 - A Mission to Explore the Pioneer Anomaly JF - Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588) Y1 - 2005 SN - 9290928999 N1 - ISBN der CD-ROM-Ausg.: 9290928999 ; Symposium Trends in Space Science and Cosmic Vision 2020 <2005, Noordwijk> ; ESLAB symposium <39,2005, Noordwijk> ; European Space Laboratory ; Report Number: LA-UR-05-4907 ; The Pioneer Explorer Collaboration SP - 3 EP - 10 PB - ESA Publ. Div. CY - Noordwijk ER -