TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. A1 - Richter, L. T1 - Multiple Rendezvous and Sample Return Missions to Near-Earth Asteroids Using Solar Sailcraft JF - Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris] Y1 - 2003 SN - 92-9092-853-0 N1 - International Conference on Low Cost Planetary Missions <5, 2003, Noordwijk> ; International Academy of Astronautics ; European Space Research and Technology Centre SP - 351 EP - 358 PB - ESA CY - Noordwijk ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. A1 - Lämmerzahl, W. T1 - Solar Sail Propulsion: An Enabling Technology for Fundamental Physics Missions JF - Lasers, Clocks and Drag Free Control : Exploration of Relativistic Gravity in Space / by Hansjörg Dittus ..., eds. - ( Astrophysics and Space Science Library ; 349) Y1 - 2008 SN - 978-3-540-34376-9 SP - 379 EP - 398 PB - Springer CY - Berlin [u.a.] ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. A1 - Loeb, H. W A1 - Schartner, K.-H. T1 - Main Belt Asteroid Sample Return Mission Using Solar Electric Propulsion JF - Acta Astronautica. 63 (2008), H. 1-4 Y1 - 2008 SN - 0094-5765 N1 - International Astronautical Federation Congress <58, 2007, Hyderabad> ; International Astronautical Congress <58, 2007, Hyderabad> ; IAC-07-A3.5.07 SP - 91 EP - 101 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. 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 - Dachwald, Bernd A1 - Seboldt, W. T1 - Solar Sails for Near- and Medium-Term Scientific Deep Space Missions / W. Sebolt ; B. Dachwald JF - In-space propulsion : edited book of proceedings of the 10-IWCP, the 10th International Workshop on Combustion and Propulsion held in Lerici, La Spezia, Italy, 21-25 September 2003 / [ed.: Luigi T. DeLuca] Y1 - 2005 N1 - Paper 31 ; International workshop on combustion and propulsion <10, 2003, Lerici> PB - SP Lab, Politecnico di Milano CY - Milano ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. T1 - Solar Sails — Propellantless Propulsion for Near- and Medium-Term Deep-Space Missions / W. Seboldt ; B. Dachwald JF - Advanced Propulsion Systems and Technologies, Today to 2020 / Claudio Bruno (ed.) ... - (Progress in Astronautics and Aeronautics Series ; 223) Y1 - 2008 SN - 978-1-56347-929-8 N1 - ISBN 10: 1-56347-929-X ; American Institute of Aeronautics and Astronautics PB - AIAA CY - Reston, Va. 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 - JOUR A1 - Dachwald, Bernd A1 - Schmidt, Tanja D. A1 - Seboldt, Wolfgang A1 - Auweter-Kurtz, T1 - Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika Y1 - 2003 N1 - 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 20-23 July 2003, Huntsville, Alabama ; AIAA 2003-4573 SP - 1 EP - 9 PB - - ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ohndorf, A. A1 - Wie, Bong T1 - Solar Sail Trajectory Optimization for the Solar Polar Imager (SPI) Mission 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-2006-6177 PB - American Institute of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ohndorf, A. A1 - Gill, E. T1 - Optimization of low-thrust Earth-Moon transfers using evolutionary neurocontrol / Ohndorf, A. ; Dachwald, B. ; Gill, E. JF - IEEE Congress on Evolutionary Computation, 2009. CEC '09. Y1 - 2009 SN - 978-1-4244-2958-5 SP - 358 EP - 364 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ohndorf, A. T1 - 1st ACT Global Trajectory Optimisation Competition : Results found at DLR JF - Acta Astronautica. 61 (2007), H. 9 Y1 - 2007 SN - 0094-5765 N1 - Global Trajectory Optimization ; Results of the First Competition Organised by the Advanced Concept Team (ACT) of the European Space Agency (ESA) SP - 742 EP - 752 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mikucki, Jill A1 - Tulaczyk, Slawek A1 - Digel, Ilya A1 - Espe, Clemens A1 - Feldmann, Marco A1 - Francke, Gero A1 - Kowalski, Julia A1 - Xu, Changsheng T1 - IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems JF - Annals of Glaciology N2 - There is significant interest in sampling subglacial environments for geobiological studies, but they are difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The IceMole is a maneuverable subsurface ice probe for clean in situ analysis and sampling of glacial ice and subglacial materials. The design is based on the novel concept of combining melting and mechanical propulsion. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland. They demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. A more advanced probe is currently under development as part of the Enceladus Explorer (EnEx) project. It offers systems for obstacle avoidance, target detection, and navigation in ice. For the EnEx-IceMole, we will pay particular attention to clean protocols for the sampling of subglacial materials for biogeochemical analysis. We plan to use this probe for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, with return of a subglacial brine sample. KW - Antarctic Glaciology KW - Extraterrestrial Glaciology KW - Glaciological instruments and methods KW - Subclacial exploration KW - Subglacial lakes Y1 - 2014 U6 - https://doi.org/10.3189/2014AoG65A004 SN - 1727-5644 VL - 55 IS - 65 SP - 14 EP - 22 PB - Cambridge University Press CY - Cambridge ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mengali, Giovanni A1 - Quarta, Alessandro A. A1 - Circi, Christian T1 - Refined Solar Sail Force Model with Mission Application / Giovanni Mengali ; Alessandro A. Quarta , Christian Circi ; Bernd Dachwald JF - Journal of Guidance, Control, and Dynamics. 30 (2007), H. 2 Y1 - 2007 SN - 0162-3192 N1 - 2. ISBN: 0731-5090 SP - 512 EP - 520 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 - JOUR A1 - Dachwald, Bernd A1 - McDonald, Malcolm A1 - McInnes, Colin R. A1 - Mengali, Giovanni T1 - Impact of Optical Degradation on Solar Sail Mission Performance JF - Journal of Spacecraft and Rockets. 44 (2007), H. 4 Y1 - 2007 SN - 0022-4650 N1 - 2. ISSN: 1533-6794 SP - 740 EP - 749 ER - TY - JOUR A1 - Dachwald, Bernd A1 - MacDonald, Malcolm A1 - McInnes, Colin R. T1 - Heliocentric Solar Sail Orbit Transfers with Locally Optimal Control Laws / Malcolm Macdonald ; Colin McInnes ; Bernd Dachwald JF - Journal of Spacecraft and Rockets. 44 (2007), H. 1 Y1 - 2007 SN - 0022-4650 SP - 273 EP - 276 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Leipold, M. A1 - Fichtner, H. T1 - Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System / M. Leipold ; H. Fichtner ; B. Heber ... B. Dachwald ... JF - Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris] Y1 - 2003 SN - 92-9092-853-0 N1 - International Conference on Low Cost Planetary Missions <5, 2003, Noordwijk> ; International Academy of Astronautics ; European Space Research and Technology Centre SP - 367 EP - 375 PB - ESA CY - Noordwijk 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 - Carnelli, Ian A1 - Vasile, Massimiliano T1 - Evolutionary Neurocontrol: A Novel Method for Low-Thrust Gravity-Assist Trajectory Optimization / Carnelli, Ian ; Dachwald, Bernd ; Vasile, Massimiliano JF - Journal of guidance control and dynamics. 32 (2009), H. 2 Y1 - 2009 SN - 0731-5090 SP - 616 EP - 625 PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Carnelli, I. A1 - Vasile, M. T1 - Optimizing low-thrust gravity assist interplanetary trajectories using evolutionary neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile JF - IEEE Congress on Evolutionary Computation, 2007 : CEC 2007 ; 25 - 28 September 2007, Singapore Y1 - 2007 SN - 978-1-424-41339-3 N1 - ISBN 10: 1-424-41339-7 ; IEEE Congress on Evolutionary Computation <2007, Singapore> ; Institute of Electrical and Electronics Engineers ; Nebent: CEC 2007 ; Parallel als Online-Ausg. erschienen SP - 965 EP - 972 PB - IEEE Service Center CY - Piscataway, NJ ER - TY - JOUR A1 - Dachwald, Bernd A1 - Carnelli, I. A1 - Vasile, M. T1 - Evolutionary Neurocontrol as a Novel Method for Low-Thrust Gravity Assist Trajectory Optimization / I. Carnelli ; B. Dachwald ; M. Vasile JF - Proceedings of the Twenty-Fifth International Symposium on Space Technology and Science (Selected papers) : Kanazawa, [June 4 through June 11, 2006, at Kanazawa-shi Kanko Kaikan in Kanazawa city] / [Japan Society for Aeronautical and Space Sciences. Kohtaro Matsumoto [ed.-in-chief] Y1 - 2006 SN - 4-99005-002-9 N1 - International Symposium on Space Technology and Science <25, 2006, Kanazawa> ; ISTS 2006-d-46 SP - 569 EP - 574 PB - JSASS CY - Tokyo ER - TY - JOUR A1 - Dachwald, Bernd A1 - Carnelli, I. A1 - Vasile, M. T1 - Low-Thrust Gravity Assist Trajectory Optimization Using Evolutionary Neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile ... JF - Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3) Y1 - 2006 SN - 0-87703-527-X N1 - Astrodynamics Conference <2005, South Lake Tahoe, Calif.> ; American Astronautical Society ; Number: AAS-05-374 SP - 1911 EP - 1928 PB - Univelt CY - San Diego, Calif. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Baturkin, Volodymyr A1 - Coverstone, Victoria L. A1 - Dietrich, Benjamin A1 - Garbe, Gregory P. A1 - Görlich, Marianne A1 - Leipold, Manfred A1 - Lura, Franz A1 - Macdonald, Malcolm A1 - McInnes, Colin R. A1 - Mengali, Giovanni A1 - Quatra, Alessandro A. A1 - Rios-Reyes, Leonel A1 - Scheeres, Daniel J. A1 - Seboldt, Wolfgang A1 - Wie, Bong T1 - Potential Effects of Optical Solar Sail Degradation on Interplanetary Trajectory Design JF - Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3) Y1 - 2006 UR - http://www.spacesailing.net/paper/200508_LakeTahoe_Dachwald+.pdf SN - 0-87703-527-X N1 - Astrodynamics Conference <2005, South Lake Tahoe, Calif.> ; American Astronautical Society ; Number: AAS-05-413 SP - 2569 EP - 2592 PB - Univelt CY - San Diego, Calif. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ball, Andrew J. A1 - Ulamec, Stephan A1 - Price, Michael E. T1 - A small mission for in situ exploration of a primitive binary near-Earth asteroid / Ball, Andrew J. ; Ulamec, Stephan ; Dachwald, Bernd ; Price, Michael E. ; [u.a.] JF - Advances in Space Research. 43 (2009), H. 2 Y1 - 2009 SN - 0273-1177 SP - 317 EP - 324 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimization of very-low-thrust trajectories using evolutionary neurocontrol JF - Acta Astronautica. 57 (2005), H. 2-8 Y1 - 2005 SN - 0094-5765 SP - 175 EP - 185 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Interplanetary Mission Analysis for Non-Perfectly Reflecting Solar Sailcraft Using Evolutionary Neurocontrol JF - Astrodynamics 2003 : proceedings of the AAS/AIAA Astrodynamics Conference held August 3 - 7, 2003, Big Sky, Montana / ed. by Jean de Lafontaine. - Pt. 2. - (Advances in the astronautical sciences ; 116,2) Y1 - 2004 SN - 0-87703-509-1 N1 - Astrodynamics Conference <2003, Big Sky, Mont.> ; American Institute of Aeronautics and Astronautics ; AAS-03-579 SP - 1247 EP - 1262 PB - Univelt CY - San Diego, Calif. ER - TY - JOUR A1 - Dachwald, Bernd T1 - Low-Thrust Trajectory Optimization and Interplanetary Mission Analysis Using Evolutionary Neurocontrol JF - Deutscher Luft- und Raumfahrtkongress 2004 : Dresden, 20. bis 23. September 2004, Motto: Luft- und Raumfahrt - Brücke für eine wissensbasierte Gesellschaft / Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V. (DGLR). [Red.: Peter Brandt (verantwortlich)]. - Bd. 2. - (Jahrbuch ... der Deutschen Gesellschaft für Luft- und Raumfahrt) Y1 - 2004 N1 - Deutscher Luft- und Raumfahrt-Kongress <2004, Dresden> ; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth ; DGLR-2004-116 SP - 917 EP - 926 CY - Bonn ER - TY - JOUR A1 - Dachwald, Bernd T1 - Evolutionary Neurocontrol: A Smart Method for Global Optimization of Low-Thrust Trajectories JF - 22nd AIAA Applied Aerodynamics Conference and Exhibit - AIAA/AAS Astrodynamics Specialist Conference and Exhibit - AIAA Guidance, Navigation, and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : 16 - 19 August 2004, Providence, Rhode Island / American Institute of Aeronautics and Astronautics. - (AIAA meeting papers on disc ; 2004,14-15) Y1 - 2004 N1 - American Institute of Aeronautics and Astronautics ; AIAA/AAS Astrodynamics Specialist Conference and Exhibit <2004, Providence, RI> ; AIAA paper number: AIAA-2004-5405 PB - American Inst. of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimal Solar Sail Trajectories for Missions to the Outer Solar System JF - 22nd AIAA Applied Aerodynamics Conference and Exhibit - AIAA/AAS Astrodynamics Specialist Conference and Exhibit - AIAA Guidance, Navigation, and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : 16 - 19 August 2004, Providence, Rhode Island / American Institute of Aeronautics and Astronautics. - (AIAA meeting papers on disc ; 2004,14-15) Y1 - 2004 N1 - American Institute of Aeronautics and Astronautics ; AIAA/AAS Astrodynamics Specialist Conference and Exhibit <2004, Providence, RI> ; AIAA paper number: AIAA-2004-5406 PB - American Inst. of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd T1 - Minimum Transfer Times for Nonperfectly Reflecting Solar Sailcraft JF - Journal of Spacecraft and Rockets. 41 (2004), H. 4 Y1 - 2004 SN - 0022-4650 N1 - 2. ISSN: 1533-6794 SP - 693 EP - 695 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimal Solar Sail Trajectories for Missions to the Outer Solar System JF - Journal of guidance, control, and dynamics. 28 (2005), H. 6 Y1 - 2005 SN - 0162-3192 N1 - 2. ISSN: 0162-3192. - 3. ISSN: 0731-5090 SP - 1187 EP - 1193 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimization of Interplanetary Solar Sailcraft Trajectories Using Evolutionary Neurocontrol JF - Journal of guidance, control, and dynamics. 27 (2004), H. 1 Y1 - 2004 SN - 0162-3192 N1 - 2. ISSN: 0162-3192. - 3. ISSN: 0731-5090 SP - 66 EP - 72 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 - Czupalla, Markus A1 - Horneck, G. A1 - Blome, Hans-Joachim T1 - The conceptual design of a hybrid life support system based on the evaluation and comparison of terrestrial testbeds JF - Advances in Space Research Y1 - 2005 SN - 0273-1177 VL - 35 IS - 9 SP - 1609 EP - 1620 ER - TY - JOUR A1 - Czarnecki, Christian A1 - Winkelmann, Axel A1 - Spiliopoulou, Myra T1 - Services in electronic telecommunication markets: a framework for planning the virtualization of processes JF - Electronic Markets N2 - The potential of electronic markets in enabling innovative product bundles through flexible and sustainable partnerships is not yet fully exploited in the telecommunication industry. One reason is that bundling requires seamless de-assembling and re-assembling of business processes, whilst processes in telecommunication companies are often product-dependent and hard to virtualize. We propose a framework for the planning of the virtualization of processes, intended to assist the decision maker in prioritizing the processes to be virtualized: (a) we transfer the virtualization pre-requisites stated by the Process Virtualization Theory in the context of customer-oriented processes in the telecommunication industry and assess their importance in this context, (b) we derive IT-oriented requirements for the removal of virtualization barriers and highlight their demand on changes at different levels of the organization. We present a first evaluation of our approach in a case study and report on lessons learned and further steps to be performed. KW - Telecommunication KW - Services KW - Process virtualization KW - Product bundling KW - Transformation Y1 - 2010 U6 - https://doi.org/10.1007/s12525-010-0045-8 SN - 1422-8890 VL - 20 IS - 3-4 SP - 197 EP - 207 PB - Springer CY - Berlin ER - TY - JOUR A1 - Czarnecki, Christian A1 - Spiliopoulou, Myra T1 - A holistic framework for the implementation of a next generation network JF - International Journal of Business Information Systems N2 - As the potential of a next generation network (NGN) is recognised, telecommunication companies consider switching to it. Although the implementation of an NGN seems to be merely a modification of the network infrastructure, it may trigger or require changes in the whole company, because it builds upon the separation between service and transport, a flexible bundling of services to products and the streamlining of the IT infrastructure. We propose a holistic framework, structured into the layers ‘strategy’, ‘processes’ and ‘information systems’ and incorporate into each layer all concepts necessary for the implementation of an NGN, as well as the alignment of these concepts. As a first proof-of-concept for our framework we have performed a case study on the introduction of NGN in a large telecommunication company; we show that our framework captures all topics that are affected by an NGN implementation. KW - next generation network KW - telecommunication KW - NGN KW - IP-based networks KW - product bundling Y1 - 2012 U6 - https://doi.org/10.1504/IJBIS.2012.046291 SN - 1746-0972 VL - 9 IS - 4 SP - 385 EP - 401 PB - Inderscience Enterprises CY - Olney, Bucks ER - TY - JOUR A1 - Cosma, Cosmin A1 - Kessler, Julia A1 - Gebhardt, Andreas A1 - Campbell, Ian A1 - Balc, Nicolae T1 - Improving the Mechanical Strength of Dental Applications and Lattice Structures SLM Processed JF - Materials N2 - To manufacture custom medical parts or scaffolds with reduced defects and high mechanical characteristics, new research on optimizing the selective laser melting (SLM) parameters are needed. In this work, a biocompatible powder, 316L stainless steel, is characterized to understand the particle size, distribution, shape and flowability. Examination revealed that the 316L particles are smooth, nearly spherical, their mean diameter is 39.09 μm and just 10% of them hold a diameter less than 21.18 μm. SLM parameters under consideration include laser power up to 200 W, 250–1500 mm/s scanning speed, 80 μm hatch spacing, 35 μm layer thickness and a preheated platform. The effect of these on processability is evaluated. More than 100 samples are SLM-manufactured with different process parameters. The tensile results show that is possible to raise the ultimate tensile strength up to 840 MPa, adapting the SLM parameters for a stable processability, avoiding the technological defects caused by residual stress. Correlating with other recent studies on SLM technology, the tensile strength is 20% improved. To validate the SLM parameters and conditions established, complex bioengineering applications such as dental bridges and macro-porous grafts are SLM-processed, demonstrating the potential to manufacture medical products with increased mechanical resistance made of 316L. Y1 - 2020 U6 - https://doi.org/10.3390/ma13040905 SN - 1996-1944 VL - 13 IS - 4 SP - 1 EP - 18 PB - MDPI CY - Basel ER - TY - JOUR A1 - Cornelis, Peter A1 - Givanoudi, Stella A1 - Yongabi, Derick A1 - Iken, Heiko A1 - Duwé, Sam A1 - Deschaume, Olivier A1 - Robbens, Johan A1 - Dedecker, Peter A1 - Bartic, Carmen A1 - Wübbenhorst, Michael A1 - Schöning, Michael Josef A1 - Heyndrickx, Marc A1 - Wagner, Patrick T1 - Sensitive and specific detection of E. coli using biomimetic receptors in combination with a modified heat-transfer method JF - Biosensors and Bioelectronics Y1 - 2019 U6 - https://doi.org/10.1016/j.bios.2019.04.026 SN - 0956-5663 VL - 136 SP - 97 EP - 105 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Conzen, Catharina A1 - Albanna, Walid A1 - Weiss, Miriam A1 - Kürten, David A1 - Vilser, Walthard A1 - Kotliar, Konstantin A1 - Zäske, Charlotte A1 - Clusmann, Hans A1 - Schubert, Gerrit Alexander T1 - Vasoconstriction and Impairment of Neurovascular Coupling after Subarachnoid Hemorrhage: a Descriptive Analysis of Retinal Changes JF - Translational Stroke Research N2 - Impaired cerebral autoregulation and neurovascular coupling (NVC) contribute to delayed cerebral ischemia after subarachnoid hemorrhage (SAH). Retinal vessel analysis (RVA) allows non-invasive assessment of vessel dimension and NVC hereby demonstrating a predictive value in the context of various neurovascular diseases. Using RVA as a translational approach, we aimed to assess the retinal vessels in patients with SAH. RVA was performed prospectively in 24 patients with acute SAH (group A: day 5–14), in 11 patients 3 months after ictus (group B: day 90 ± 35), and in 35 age-matched healthy controls (group C). Data was acquired using a Retinal Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and NVC using flicker-light excitation. Diameter of retinal vessels—central retinal arteriolar and venular equivalent—was significantly reduced in the acute phase (p < 0.001) with gradual improvement in group B (p < 0.05). Arterial NVC of group A was significantly impaired with diminished dilatation (p < 0.001) and reduced area under the curve (p < 0.01) when compared to group C. Group B showed persistent prolonged latency of arterial dilation (p < 0.05). Venous NVC was significantly delayed after SAH compared to group C (A p < 0.001; B p < 0.05). To our knowledge, this is the first clinical study to document retinal vasoconstriction and impairment of NVC in patients with SAH. Using non-invasive RVA as a translational approach, characteristic patterns of compromise were detected for the arterial and venous compartment of the neurovascular unit in a time-dependent fashion. Recruitment will continue to facilitate a correlation analysis with clinical course and outcome. Y1 - 2018 U6 - https://doi.org/10.1007/s12975-017-0585-8 SN - 1868-601X IS - 9 SP - 284 EP - 293 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Colombo, Daniele A1 - Drira, Slah A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - An element-based formulation for ES-FEM and FS-FEM models for implementation in standard solid mechanics finite element codes for 2D and 3D static analysis JF - International Journal for Numerical Methods in Engineering N2 - Edge-based and face-based smoothed finite element methods (ES-FEM and FS-FEM, respectively) are modified versions of the finite element method allowing to achieve more accurate results and to reduce sensitivity to mesh distortion, at least for linear elements. These properties make the two methods very attractive. However, their implementation in a standard finite element code is nontrivial because it requires heavy and extensive modifications to the code architecture. In this article, we present an element-based formulation of ES-FEM and FS-FEM methods allowing to implement the two methods in a standard finite element code with no modifications to its architecture. Moreover, the element-based formulation permits to easily manage any type of element, especially in 3D models where, to the best of the authors' knowledge, only tetrahedral elements are used in FS-FEM applications found in the literature. Shape functions for non-simplex 3D elements are proposed in order to apply FS-FEM to any standard finite element. KW - distorted element KW - ES-FEM KW - FS-FEM KW - non-simplex S-FEM elements KW - S-FEM Y1 - 2022 U6 - https://doi.org/10.1002/nme.7126 SN - 1097-0207 VL - 124 IS - 2 SP - 402 EP - 433 PB - Wiley CY - Chichester ER - TY - JOUR A1 - Coll-Perales, Baldomero A1 - Schulte-Tigges, Joschua A1 - Rondinone, Michele A1 - Gozalvez, Javier A1 - Reke, Michael A1 - Matheis, Dominik A1 - Walter, Thomas T1 - Prototyping and evaluation of infrastructure-assisted transition of control for cooperative automated vehicles JF - IEEE Transactions on Intelligent Transportation Systems N2 - Automated driving is now possible in diverse road and traffic conditions. However, there are still situations that automated vehicles cannot handle safely and efficiently. In this case, a Transition of Control (ToC) is necessary so that the driver takes control of the driving. Executing a ToC requires the driver to get full situation awareness of the driving environment. If the driver fails to get back the control in a limited time, a Minimum Risk Maneuver (MRM) is executed to bring the vehicle into a safe state (e.g., decelerating to full stop). The execution of ToCs requires some time and can cause traffic disruption and safety risks that increase if several vehicles execute ToCs/MRMs at similar times and in the same area. This study proposes to use novel C-ITS traffic management measures where the infrastructure exploits V2X communications to assist Connected and Automated Vehicles (CAVs) in the execution of ToCs. The infrastructure can suggest a spatial distribution of ToCs, and inform vehicles of the locations where they could execute a safe stop in case of MRM. This paper reports the first field operational tests that validate the feasibility and quantify the benefits of the proposed infrastructure-assisted ToC and MRM management. The paper also presents the CAV and roadside infrastructure prototypes implemented and used in the trials. The conducted field trials demonstrate that infrastructure-assisted traffic management solutions can reduce safety risks and traffic disruptions. KW - Automated driving KW - automated vehicles KW - connected automated vehicles KW - CAV KW - experimental evaluation Y1 - 2021 U6 - https://doi.org/10.1109/TITS.2021.3061085 SN - 1524-9050 (Print) SN - 1558-0016 (Online) VL - 23 IS - 7 SP - 6720 EP - 6736 PB - IEEE ER - TY - JOUR A1 - Clausnitzer, Julian A1 - Kleefeld, Andreas T1 - A spectral Galerkin exponential Euler time-stepping scheme for parabolic SPDEs on two-dimensional domains with a C² boundary JF - Discrete and Continuous Dynamical Systems - Series B N2 - We consider the numerical approximation of second-order semi-linear parabolic stochastic partial differential equations interpreted in the mild sense which we solve on general two-dimensional domains with a C² boundary with homogeneous Dirichlet boundary conditions. The equations are driven by Gaussian additive noise, and several Lipschitz-like conditions are imposed on the nonlinear function. We discretize in space with a spectral Galerkin method and in time using an explicit Euler-like scheme. For irregular shapes, the necessary Dirichlet eigenvalues and eigenfunctions are obtained from a boundary integral equation method. This yields a nonlinear eigenvalue problem, which is discretized using a boundary element collocation method and is solved with the Beyn contour integral algorithm. We present an error analysis as well as numerical results on an exemplary asymmetric shape, and point out limitations of the approach. KW - Nonlinear eigenvalue problems KW - Boundary integral equations, KW - Exponential Euler scheme, KW - Parabolic SPDEs Y1 - 2024 U6 - https://doi.org/10.3934/dcdsb.2023148 SN - 1531-3492 SN - 1553-524X (eISSN) VL - 29 IS - 4 SP - 1624 EP - 1651 PB - AIMS CY - Springfield ER - TY - JOUR A1 - Claessens, J. A1 - Fuchsberger, A. A1 - Günther, C. A1 - Horn, G. A1 - Howker, K. A1 - Hulsebosch, R.J. A1 - Mitchell, C. A1 - Paterson, K. A1 - Preneel, B. A1 - Schellekens, D. A1 - Schuba, Marko T1 - Pioneering Advanced Mobile Privacy and Security Y1 - 2003 N1 - electronic proceedings of the 18th IFIP International Information Security Conference, Athens, Greece, May 2003 SP - 1 EP - 17 ER - TY - JOUR A1 - Claer, Mario A1 - Ferrein, Alexander A1 - Schiffer, Stefan T1 - Calibration of a Rotating or Revolving Platform with a LiDAR Sensor JF - Applied Sciences Y1 - 2019 U6 - https://doi.org/10.3390/app9112238 SN - 2076-3417 VL - Volume 9 IS - issue 11, 2238 PB - MDPI CY - Basel ER - TY - JOUR A1 - Ciritsis, Alexander A1 - Horbach, Andreas A1 - Staat, Manfred A1 - Kuhl, Christiane K. A1 - Kraemer, Nils Andreas T1 - Porosity and tissue integration of elastic mesh implants evaluated in vitro and in vivo JF - Journal of Biomedical Materials Research: Part B: Applied Biomaterials N2 - Purpose In vivo, a loss of mesh porosity triggers scar tissue formation and restricts functionality. The purpose of this study was to evaluate the properties and configuration changes as mesh deformation and mesh shrinkage of a soft mesh implant compared with a conventional stiff mesh implant in vitro and in a porcine model. Material and Methods Tensile tests and digital image correlation were used to determine the textile porosity for both mesh types in vitro. A group of three pigs each were treated with magnetic resonance imaging (MRI) visible conventional stiff polyvinylidene fluoride meshes (PVDF) or with soft thermoplastic polyurethane meshes (TPU) (FEG Textiltechnik mbH, Aachen, Germany), respectively. MRI was performed with a pneumoperitoneum at a pressure of 0 and 15 mmHg, which resulted in bulging of the abdomen. The mesh-induced signal voids were semiautomatically segmented and the mesh areas were determined. With the deformations assessed in both mesh types at both pressure conditions, the porosity change of the meshes after 8 weeks of ingrowth was calculated as an indicator of preserved elastic properties. The explanted specimens were examined histologically for the maturity of the scar (collagen I/III ratio). Results In TPU, the in vitro porosity increased constantly, in PVDF, a loss of porosity was observed under mild stresses. In vivo, the mean mesh areas of TPU were 206.8 cm2 (± 5.7 cm2) at 0 mmHg pneumoperitoneum and 274.6 cm2 (± 5.2 cm2) at 15 mmHg; for PVDF the mean areas were 205.5 cm2 (± 8.8 cm2) and 221.5 cm2 (± 11.8 cm2), respectively. The pneumoperitoneum-induced pressure increase resulted in a calculated porosity increase of 8.4% for TPU and of 1.2% for PVDF. The mean collagen I/III ratio was 8.7 (± 0.5) for TPU and 4.7 (± 0.7) for PVDF. Conclusion The elastic properties of TPU mesh implants result in improved tissue integration compared to conventional PVDF meshes, and they adapt more efficiently to the abdominal wall. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 827–833, 2018. Y1 - 2018 U6 - https://doi.org/10.1002/jbm.b.33877 SN - 1552-4981 VL - 106 IS - 2 SP - 827 EP - 833 PB - Wiley CY - New York, NY ER - TY - JOUR A1 - Ciobanu, Octavian A1 - Staat, Manfred A1 - Rahimi, Alireza T1 - The use of open source software in biomechanical finite element analysis JF - Buletinul Institutului Politehnic din Iaşi / Universitatea Tehnică Gh. Asachi, Iaşi Secţia 5, Construcţii de maşini = Machine construction = Bulletin of the Polytechnic Institute of Jassy = Izvestija Jasskogo Politechničeskogo Instituta Y1 - 2008 SN - 1011-2855 VL - 54 IS - 7/8 SP - 213 EP - 220 ER - TY - JOUR A1 - Chwallek, Constanze A1 - Nawrath, Lara A1 - Krastina, Anzelika A1 - Bruksle, Ieva T1 - Supportive research on sustainable entrepreneurship and business practices JF - SECA Sustainable Entrepreneurship for Climate Action Y1 - 2024 SN - 978-952-316-514-4 (pdf) SN - 2954-1654 (on-line publication) IS - 3 PB - Lapland University of Applied Sciences Ltd CY - Rovaniemi ER - TY - JOUR A1 - Chudoba, Rostislav A1 - Butenweg, Christoph A1 - Peiffer, F. T1 - Technical information system for collaborative material research JF - Advances in engineering software Y1 - 2004 U6 - https://doi.org/10.1016/j.advengsoft.2004.03.021 SN - 1873-5339 (E-Journal); 0965-9978 (Print) VL - Volume 35 IS - Issue 10-11 SP - 747 EP - 756 ER - TY - JOUR A1 - Christoph, Thomas A1 - Bahrenberg, Gregor A1 - Vry, Jean de A1 - Englberger, Werner A1 - Erdmann, Volker A. A1 - Frech, Moritz A1 - Kögel, Babette A1 - Röhl, Thomas A1 - Schiene, Klaus A1 - Schröder, Wolfgang A1 - Seibler, Jost A1 - Kurreck, Jens T1 - Investigation of TRPV1 loss-of-function phenotypes in transgenic shRNA expressing and knockout mice JF - Molecular and Cellular Neuroscience Y1 - 2008 U6 - https://doi.org/10.1016/j.mcn.2007.12.006 SN - 1044-7431 VL - 37 IS - 3 SP - 579 EP - 589 ER - TY - JOUR A1 - Christiaens, P. A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Wagner, Torsten A1 - Bijnens, N. A1 - Williams, O. A. A1 - Daenen, M. A1 - Haenen, K. A1 - Schöning, Michael Josef A1 - Wagner, P. T1 - Nanocrystalline diamond-based field-effect capacitive pH sensor JF - Transducers '07 Eurosensors XXI : digest of technical papers ; the14th International Conference on Solid-State Sensors, Actuators and Microsystems, June 10-14, 2007, Lyon, France / Gilles Delapierre (Ed.) Y1 - 2007 SN - 1-4244-0841-5 N1 - Eurosensors 21, 2007, Lyon ; International Conference on Solid-State Sensors, Actuators and Microsystems 14, 2007, Lyon SP - 1891 EP - 1894 PB - IEEE CY - Piscataway ER -