TY - CHAP A1 - Kuhlmann, Wolfram A1 - Butenweg, Christoph A1 - Lopez, Marijen A1 - Fernandez, Sebastian T1 - Seismic vulnerability assessment of the historic Aachen Cathedral T2 - Conference proceedings / 13th World Conference on Earthquake Engineering [Vancouver, British Columbia, Canada, August 1 - 6, 2004] / [hosted by CAEE/ACGP, Canadian Association for Earthquake Engineering] Y1 - 2004 SP - 1 EP - 14 PB - CAEE CY - Vancouver ER - TY - CHAP A1 - Kuhlmann, Wolfram A1 - Butenweg, Christoph A1 - Bettzieche, Volker A1 - Meskouris, Konstantin T1 - Experimentelle und numerische Untersuchungen zur baudynamischen Beurteilung von Talsperren des Ruhrverbandes T2 - 13. Deutsches Talsperrensymposium in Weimar Y1 - 2004 SP - 1 EP - 26 ER - TY - CHAP A1 - Butenweg, Christoph A1 - Bettzieche, Volker A1 - Kuhlmann, Wolfram A1 - Meskouris, Konstantin T1 - Die baudynamische Beurteilung von Talsperren am Beispiel der Fürwiggetalsperre T2 - Berichte der Fachtagung Baustatik - Baupraxis 9 am 14. und 15. März 2005 in Dresden / Institut für Statik und Dynamik der Tragwerke, TU Dresden, Deutschland Y1 - 2005 SN - 3-00-015456-6 SP - 73 EP - 84 PB - Inst. für Statik und Dynamik der Tragwerke CY - Dresden ER - TY - CHAP A1 - Meskouris, Konstantin A1 - Butenweg, Christoph A1 - Mistler, Michael A1 - Kuhlmann, Wolfram T1 - Seismic behaviour of historic masonry buildings T2 - 7th National Congress on Mechanics : Chania, Crete, June 24 - 26, 2004 ; proceedings / ed. A. Kounadis .... Y1 - 2004 SP - 47 EP - 49 PB - Hellenic Society for Theoretical and Applied Mechanics CY - Chania ER - TY - CHAP A1 - Eggert, Mathias A1 - Weber, Jannik T1 - What drives the purchase decision in Instagram stores? T2 - ECIS 2023 Research Papers N2 - The popularity of social media and particularly Instagram grows steadily. People use the different platforms to share pictures as well as videos and to communicate with friends. The potential of social media platforms is also being used for marketing purposes and for selling products. While for Facebook and other online social media platforms the purchase decision factors are investigated several times, Instagram stores remain mainly unattended so far. The present research work closes this gap and sheds light into decisive factors for purchasing products offered in Instagram stores. A theoretical research model, which contains selected constructs that are assumed to have a significant influence on Instagram user´s purchase intention, is developed. The hypotheses are evaluated by applying structural equation modelling on survey data containing 127 relevant participants. The results of the study reveal that ‘trust’, ‘personal recommendation’, and ‘usability’ significantly influences user’s buying intention in Instagram stores. KW - Instagram store KW - shopping behavior KW - purchase factor KW - PLS KW - structural equation model Y1 - 2023 N1 - ECIS 2023, European Conference on Information Systems, Kristiansand, Norway, June 11.-16. SP - 1 EP - 17 ER - TY - CHAP A1 - Marinkovic, Marko A1 - Butenweg, Christoph T1 - Seismic behaviour of RC frames with uncoupled masonry infills having two storeys or two bays T2 - Brick and Block Masonry - From Historical to Sustainable Masonry. Proceedings of the 17th International Brick/Block Masonry Conference N2 - Reinforced concrete (RC) structures with masonry infills are widely used for several types of buildings all over the world. However, it is well known that traditional masonry infills constructed with rigid contact to the surrounding RC frame performed rather poor in past earthquakes. Masonry infills showed severe in-plane damages and failed in many cases under out-of-plane seismic loading. As the undesired interactions between frames and infills changes the load transfer on building level, complete collapses of buildings were observed. A possible solution is uncoupling of masonry infills to the frame to reduce the infill contribution activated by the frame deformation under horizontal loading. The paper presents numerical simulations on RC frames equipped with the innovative decoupling system INODIS. The system was developed within the European project INSYSME and allows an effective uncoupling of frame and infill. The simulations are carried out with a micro-modelling approach, which is able to predict the complex nonlinear behaviour resulting from the different materials and their interaction. Each brick is modelled individually and connected taking into account nonlinearity of a brick mortar interface. The calibration of the model is based on small specimen tests and experimental results for one bay one storey frame are used for the validation. The validated model is further used for parametric studies on two storey and two bay infilled frames. The response and change of the structural stiffness are analysed and compared to the traditionally infilled frame. The results confirm the effectiveness of the INODIS system with less damage and relatively low contribution of the infill at high drift levels. In contrast to the uncoupled system configurations, traditionally infilled frames experienced brittle failure at rather low drift levels. Y1 - 2020 U6 - https://doi.org/10.1201/9781003098508-72 N1 - 17th International Brick/Block Masonry Conference (17thIB2MaC 2020), July 5-8, 2020, Kraków, Poland SP - 1 EP - 7 PB - CRC Press CY - London ER - TY - CHAP A1 - Michel, Philipp A1 - Rosin, Julia A1 - Butenweg, Christoph A1 - Klinkel, Sven T1 - Soil-dependent earthquake spectra in the analysis of liquid-storage-tanks on compliant soil T2 - Seismic design of industrial facilities 2020 N2 - A further development of the Added-Mass-Method allows the combined representation of the effects of both soil-structure-interaction and fluid-structure interaction on a liquid-filled-tank in one model. This results in a practical method for describing the dynamic fluid pressure on the tank shell during joint movement. The fluid pressure is calculated on the basis of the tank's eigenform and the earthquake acceleration and represented by additional masses on the shell. The bearing on compliant ground is represented by replacement springs, which are calculated dependent on the local soil composition. The influence of the shear modulus of the compliant soil is clearly visible in the pressure curves and the stress distribution in the shell. The acceleration spectra are also dependent on soil stiffness. According to Eurocode-8 the acceleration spectra are determined for fixed soil-classes, instead of calculating the accelerations for each site in direct dependence on the soil composition. This leads to unrealistic sudden changes in the system's response. Therefore, earthquake spectra are calculated for different soil models in direct dependence of the shear modulus. Thus, both the acceleration spectra and the replacement springs match the soil composition. This enables a reasonable and consistent calculation of the system response for the actual conditions at each site. Y1 - 2020 SN - 978-3-86359-729-0 N1 - 2nd International Conference on Seismic Design of Industrial Facilities (Aachen, Germany, March 4-5, 2020) SP - 245 EP - 254 PB - Apprimus Verlag CY - Aachen ER - TY - CHAP A1 - Markinkovic, Marko A1 - Butenweg, Christoph A1 - Pavese, A. A1 - Lanese, I. A1 - Hoffmeister, B. A1 - Pinkawa, M. A1 - Vulcu, C. A1 - Bursi, O. A1 - Nardin, C. A1 - Paolacci, F. A1 - Quinci, G. A1 - Fragiadakis, M. A1 - Weber, F. A1 - Huber, P. A1 - Renault, P. A1 - Gündel, M. A1 - Dyke, S. A1 - Ciucci, M. A1 - Marino, A. T1 - Investigation of the seismic behaviour of structural and nonstructural components in industrial facilities by means of shaking table tests T2 - Seismic design of industrial facilities 2020 Y1 - 2020 SN - 978-3-86359-729-0 N1 - 2nd International Conference on Seismic Design of Industrial Facilities (Aachen, Germany, March 4-5, 2020) SP - 159 EP - 172 PB - Apprimus Verlag CY - Aachen ER - TY - CHAP A1 - Cacciatore, Pamela A1 - Butenweg, Christoph T1 - Seismic safety of cylindrical granular material steel silos under seismic loading T2 - Seismic design of industrial facilities 2020 Y1 - 2020 SN - 978-3-86359-729-0 N1 - 2nd International Conference on Seismic Design of Industrial Facilities (Aachen, Germany, March 4-5, 2020) SP - 231 EP - 244 PB - Apprimus Verlag CY - Aachen ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Bauer, Waldemar A1 - Boden, Ralf Christian A1 - Ceriotti, Matteo A1 - Cordero, Federico A1 - Dachwald, Bernd A1 - Dumont, Etienne A1 - Grimm, Christian D. A1 - Hercik, D. A1 - Herique, A. A1 - Ho, Tra-Mi A1 - Jahnke, Rico A1 - Kofman, Wlodek A1 - Lange, Caroline A1 - Lichtenheldt, Roy A1 - McInnes, Colin R. A1 - Mikschl, Tobias A1 - Montenegro, Sergio A1 - Moore, Iain A1 - Pelivan, Ivanka A1 - Peloni, Alessandro A1 - Plettenmeier, Dirk A1 - Quantius, Dominik A1 - Reershemius, Siebo A1 - Renger, Thomas A1 - Riemann, Johannes A1 - Rogez, Yves A1 - Ruffer, Michael A1 - Sasaki, Kaname A1 - Schmitz, Nicole A1 - Seboldt, Wolfgang A1 - Seefeldt, Patric A1 - Spietz, Peter A1 - Spröwitz, Tom A1 - Sznajder, Maciej A1 - Toth, Norbert A1 - Viavattene, Giulia A1 - Wejmo, Elisabet A1 - Wolff, Friederike A1 - Ziach, Christian T1 - Responsive exploration and asteroid characterization through integrated solar sail and lander development using small spacecraft technologies T2 - IAA Planetary Defense Conference N2 - In parallel to the evolution of the Planetary Defense Conference, the exploration of small solar system bodies has advanced from fast fly-bys on the sidelines of missions to the planets to the implementation of dedicated sample-return and in-situ analysis missions. Spacecraft of all sizes have landed, touch-and-go sampled, been gently beached, or impacted at hypervelocity on asteroid and comet surfaces. More have flown by close enough to image their surfaces in detail or sample their immediate environment, often as part of an extended or re-purposed mission. And finally, full-scale planetary defense experiment missions are in the making. Highly efficient low-thrust propulsion is increasingly applied beyond commercial use also in mainstream and flagship science missions, in combination with gravity assist propulsion. Another development in the same years is the growth of small spacecraft solutions, not in size but in numbers and individual capabilities. The on-going NASA OSIRIS-REx and JAXA HAYABUSA2 missions exemplify the trend as well as the upcoming NEA SCOUT mission or the landers MINERVA-II and MASCOT recently deployed on Ryugu. We outline likely as well as possible and efficient routes of continuation of all these developments towards a propellant-less and highly efficient class of spacecraft for small solar system body exploration: small spacecraft solar sails designed for carefree handling and equipped with carried landers and application modules, for all asteroid user communities –planetary science, planetary defence, and in-situ resource utilization. This projection builds on the experience gained in the development of deployable membrane structures leading up to the successful ground deployment test of a (20 m)² solar sail at DLR Cologne and in the 20 years since. It draws on the background of extensive trajectory optimization studies, the qualified technology of the DLR GOSSAMER-1 deployment demonstrator, and the MASCOT asteroid lander. These enable ‘now-term’ as well as near-term hardware solutions, and thus responsive fast-paced development. Mission types directly applicable to planetary defense include: single and Multiple NEA Rendezvous ((M)NR) for mitigation precursor, target monitoring and deflection follow-up tasks; sail-propelled head-on retrograde kinetic impactors (RKI) for mitigation; and deployable membrane based methods to modify the asteroid’s properties or interact with it. The DLR-ESTEC GOSSAMER Roadmap initiated studies of missions uniquely feasible with solar sails such as Displaced L1 (DL1) space weather advance warning and monitoring and Solar Polar Orbiter (SPO) delivery which demonstrate the capability of near-term solar sails to achieve NEA rendezvous in any kind of orbit, from Earth-coorbital to extremely inclined and even retrograde orbits. For those mission types using separable payloads, such as SPO, (M)NR and RKI, design concepts can be derived from the separable Boom Sail Deployment Units characteristic of DLR GOSSAMER solar sail technology, nanolanders like MASCOT, or microlanders like the JAXA-DLR Jupiter Trojan Asteroid Lander for the OKEANOS mission which can shuttle from the sail to the asteroids visited and enable multiple NEA sample-return missions. These are an ideal match for solar sails in micro-spacecraft format whose launch configurations are compatible with ESPA and ASAP secondary payload platforms. Y1 - 2019 N1 - Conference: IAA Planetary Defense ConferenceAt: Washington DC, USA 29.04-03.05.2019 ER - TY - CHAP A1 - Möhren, Felix A1 - Bergmann, Ole A1 - Janser, Frank A1 - Braun, Carsten T1 - On the determination of harmonic propeller loads T2 - AIAA SCITECH 2023 Forum N2 - Dynamic loads significantly impact the structural design of propeller blades due to fatigue and static strength. Since propellers are elastic structures, deformations and aerodynamic loads are coupled. In the past, propeller manufacturers established procedures to determine unsteady aerodynamic loads and the structural response with analytical steady-state calculations. According to the approach, aeroelastic coupling primarily consists of torsional deformations. They neglect bending deformations, deformation velocities, and inertia terms. This paper validates the assumptions above for a General Aviation propeller and a lift propeller for urban air mobility or large cargo drones. Fully coupled reduced-order simulations determine the dynamic loads in the time domain. A quasi-steady blade element momentum approach transfers loads to one-dimensional finite beam elements. The simulation results are in relatively good agreement with the analytical method for the General Aviation propeller but show increasing errors for the slender lift propeller. The analytical approach is modified to consider the induced velocities. Still, inertia and velocity proportional terms play a significant role for the lift propeller due to increased elasticity. The assumption that only torsional deformations significantly impact the dynamic loads of propellers is not valid. Adequate determination of dynamic loads of such designs requires coupled aeroelastic simulations or advanced analytical procedures. Y1 - 2023 U6 - https://doi.org/10.2514/6.2023-2404 N1 - AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, Md & Online PB - AIAA ER - TY - CHAP A1 - Dachwald, Bernd T1 - Global optimization of low-thrust space missions using evolutionary neurocontrol T2 - Proceedings of the international workshop on global optimization N2 - Low-thrust space propulsion systems enable flexible high-energy deep space missions, but the design and optimization of the interplanetary transfer trajectory is usually difficult. It involves much experience and expert knowledge because the convergence behavior of traditional local trajectory optimization methods depends strongly on an adequate initial guess. Within this extended abstract, evolutionary neurocontrol, a method that fuses artificial neural networks and evolutionary algorithms, is proposed as a smart global method for low-thrust trajectory optimization. It does not require an initial guess. The implementation of evolutionary neurocontrol is detailed and its performance is shown for an exemplary mission. KW - Evolutionary Neurocontrol KW - Spacecraft Trajectory Optimization KW - Low-Thrust Propulsion Y1 - 2005 SP - 85 EP - 90 ER - TY - CHAP A1 - Schartner, Karl-Heinz A1 - Loeb, H. W. A1 - Dachwald, Bernd A1 - Ohndorf, Andreas T1 - Perspectives of electric propulsion for outer planetary and deep space missions T2 - European Planetary Science Congress 2009 N2 - Solar-electric propulsion (SEP) is superior with respect to payload capacity, flight time and flexible launch window to the conventional interplanetary transfer method using chemical propulsion combined with gravity assists. This fact results from the large exhaust velocities of electric low–thrust propulsion and is favourable also for missions to the giant planets, Kuiper-belt objects and even for a heliopause probe (IHP) as shown in three studies by the authors funded by DLR. They dealt with a lander for Europa and a sample return mission from a mainbelt asteroid [1], with the TANDEM mission [2]; the third recent one investigates electric propulsion for the transfer to the edge of the solar system. All studies are based on triple-junction solar arrays, on rf-ion thrusters of the qualified RIT-22 type and they use the intelligent trajectory optimization program InTrance [3]. Y1 - 2009 N1 - European Planetary Science Congress 2009, 13-18 September, Potsdam, Germany SP - 416 EP - 416 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Boden, Ralf A1 - Ceriotti, Matteo A1 - Dachwald, Bernd A1 - Dumont, Etienne A1 - Grimm, Christian D. A1 - Lange, Caroline A1 - Lichtenheldt, Roy A1 - Pelivan, Ivanka A1 - Peloni, Alessandro A1 - Riemann, Johannes A1 - Spröwitz, Tom A1 - Tardivel, Simon T1 - Soil to sail-asteroid landers on near-term sailcraft as an evolution of the GOSSAMER small spacecraft solar sail concept for in-situ characterization T2 - 5th IAA Planetary Defense Conference KW - multiple NEA rendezvous KW - solar sail KW - GOSSAMER-1 KW - MASCOT KW - asteroid sample return Y1 - 2017 N1 - 5th IAA Planetary Defense Conference – PDC 2017 15-19 May 2017, Tokyo, Japan ER - TY - CHAP A1 - Wolf, Martin R. A1 - Schlick, Christopher A1 - Herbst, D. A1 - Springer, J. ED - Uellner, Stefan T1 - Einflussfaktoren auf den Erfolg von Telekooperation in großen Unternehmen T2 - Computer Supported Cooperative Work (CSCW) in großen Unternehmungen : Tagungsband zum Workshop der GI-Fachgruppe 5.5.1 "CSCW in Organisationen" und dem Technologiezentrum Darmstadt der Deutschen Telekom AG vom 09. - 10. Mai 1996 Y1 - 1996 SP - 1 EP - 12 PB - Dt. Telekom CY - Darmstadt ER - TY - CHAP A1 - Bertsch, Timo A1 - Meinecke, Matthias A1 - Wolf, Martin R. A1 - Schmunk, Karina T1 - Smart-Living-Services nur gegen Daten? Process-Mining als Möglichkeit zur Steigerung der Akzeptanz! T2 - Angewandte Forschung in der Wirtschaftsinformatik 2019 : Tagungsband zur 32. AKWI-Jahrestagung / hrsg. von Martin R. Wolf, Thomas Barton, Frank Herrmann, Vera G. Meister, Christian Müller, Christian Seel N2 - Seit Jahren etablieren sich Technologien in unserem Alltag, die mit Hilfe von smarten Komponenten neue Services und Vernetzungsmöglichkeiten schaffen. Dieses Paper beschreibt die Ergebnisse einer Studie, die die Akzeptanz von IoT-gestützten, smarten Services im privaten Umfeld untersucht. Dabei wird eine zentrale Datenverarbeitung mit automatisierter Erstellung smarter Services der dezentralen Datenverarbeitung mit manueller Serviceerstellung in sieben Kategorien gegenübergestellt. Die Auswertung der Studie legt die Forschungsfrage nahe, ob das Nutzerverhalten im Kontext Smart Living nicht auch mit einem dezentralen Lösungsansatz, und somit unabhängig von großen Unternehmen, analysiert werden kann. Hierfür wird im zweiten Teil des Papers die Anwendbarkeit von Process-Mining im Bereich Smart Living untersucht und prototypisch getestet. Y1 - 2019 SN - 978-3-944330-62-4 SP - 216 EP - 226 PB - mana-Buch CY - Heide ER - TY - CHAP A1 - Dachwald, Bernd T1 - Solar sail performance requirements for missions to the outer solar system and beyond T2 - 55th International Astronautical Congress 2004 N2 - Solar sails enable missions to the outer solar system and beyond, although the solar radiation pressure decreases with the square of solar distance. For such missions, the solar sail may gain a large amount of energy by first making one or more close approaches to the sun. Within this paper, optimal trajectories for solar sail missions to the outer planets and into near interstellar space (200 AU) are presented. Thereby, it is shown that even near/medium-term solar sails with relatively moderate performance allow reasonable transfer times to the boundaries of the solar system. Y1 - 2004 U6 - https://doi.org/10.2514/6.IAC-04-S.P.11 N1 - 55th International Astronautical Congress 2004 - Vancouver, Canada SP - 1 EP - 9 ER - TY - CHAP A1 - Digel, Ilya A1 - Temiz Artmann, Aysegül A1 - Artmann, Gerhard A1 - Nojima, H. T1 - Plasma cluster ions (PCI) influence on microbial cells viability : [abstract] N2 - Recently, SHARP corporation has developed the world’s first “Plasma Cluster Ions (PCI)” air purification technology, which uses plasma discharge to generate cluster ions. The new plasma cluster device releases into the air positive and negative ions, which are harmless to humans and are able to decompose and deactivate airborne substances by chemical reactions. A lot of phenomenological tests of the PCI air purification technology on microbial cells have been conducted. And, in most cases, it has been shown that PCI demonstrate strongly pronounced killing effect. Although, the particular mechanisms of PCI action are still not evident. We studied variations in resistance to PCI among gram-positive airborne microorganisms, as well as some dose-dependent, spatial, cultural and biochemical properties of PCI action in respect of Staphylococcus spp, Enterococcus spp, Micrococcus spp. KW - Clusterion KW - Raumluft KW - Luftreiniger KW - Plasmacluster ion technology KW - Air purification Y1 - 2003 ER - TY - CHAP A1 - Bung, Daniel Bernhard T1 - A comparative study of self-aerated stepped spillway and smooth invert chute flow: the effect of step-induced macro roughness T2 - 5th Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : CG JOINT 2010 Y1 - 2010 SN - 978-7-5618-3671-2 SP - 451 EP - 456 PB - Univ. Press CY - Tianjin ER - TY - CHAP A1 - Tomić, Igor A1 - Penna, Andrea A1 - DeJong, Matthew A1 - Butenweg, Christoph A1 - Correia, António A. A1 - Candeias, Paulo X. A1 - Senaldi, Ilaria A1 - Guerrini, Gabriele A1 - Malomo, Daniele A1 - Beyer, Katrin T1 - Seismic testing of adjacent interacting masonry structures T2 - 12th International Conference on Structural Analysis of Historical Constructions (SAHC 2020) N2 - In many historical centres in Europe, stone masonry buildings are part of building aggregates, which developed when the layout of the city or village was densified. In these aggregates, adjacent buildings share structural walls to support floors and roofs. Meanwhile, the masonry walls of the façades of adjacent buildings are often connected by dry joints since adjacent buildings were constructed at different times. Observations after for example the recent Central Italy earthquakes showed that the dry joints between the building units were often the first elements to be damaged. As a result, the joints opened up leading to pounding between the building units and a complicated interaction at floor and roof beam supports. The analysis of such building aggregates is very challenging and modelling guidelines do not exist. Advances in the development of analysis methods have been impeded by the lack of experimental data on the seismic response of such aggregates. The objective of the project AIMS (Seismic Testing of Adjacent Interacting Masonry Structures), included in the H2020 project SERA, is to provide such experimental data by testing an aggregate of two buildings under two horizontal components of dynamic excitation. The test unit is built at half-scale, with a two-storey building and a one-storey building. The buildings share one common wall while the façade walls are connected by dry joints. The floors are at different heights leading to a complex dynamic response of this smallest possible building aggregate. The shake table test is conducted at the LNEC seismic testing facility. The testing sequence comprises four levels of shaking: 25%, 50%, 75% and 100% of nominal shaking table capacity. Extensive instrumentation, including accelerometers, displacement transducers and optical measurement systems, provides detailed information on the building aggregate response. Special attention is paid to the interface opening, the globa KW - Historical centres KW - Stone masonry KW - Adjacent buildings KW - Shake table test Y1 - 2020 U6 - https://doi.org/10.23967/sahc.2021.234 N1 - 12th International Conference on Structural Analysis of Historical Constructions (SAHC 2021), September 29-30 and October 1, 2021, online N1 - (SAHC 2020 ursprünglich geplant für September 2020 in Barelona - verschoben wg. Covid-Pandemie) SP - 1 EP - 12 ER - TY - CHAP A1 - Dachwald, Bernd A1 - Xu, Changsheng A1 - Feldmann, Marco A1 - Plescher, Engelbert T1 - IceMole : Development of a novel subsurface ice probe and testing of the first prototype on the Morteratsch Glacier T2 - EGU General Assembly 2011 Vienna | Austria | 03 – 08 April 2011 N2 - We present the novel concept of a combined drilling and melting probe for subsurface ice research. This probe, named “IceMole”, is currently developed, built, and tested at the FH Aachen University of Applied Sciences’ Astronautical Laboratory. Here, we describe its first prototype design and report the results of its field tests on the Swiss Morteratsch glacier. Although the IceMole design is currently adapted to terrestrial glaciers and ice shields, it may later be modified for the subsurface in-situ investigation of extraterrestrial ice, e.g., on Mars, Europa, and Enceladus. If life exists on those bodies, it may be present in the ice (as life can also be found in the deep ice of Earth). Y1 - 2011 ER - TY - CHAP A1 - Wolf, Martin R. A1 - Wiedenmaier, S. A1 - Schlick, Christopher ED - Herrmann, Thomas T1 - Flexible Kooperation durch computergestützte Teamarbeit T2 - Groupware und organisatorische Innovation : Tagungsband der Deutschen Fachtagung zu Computer Supported Cooperative Work. - (Berichte des German Chapter of the ACM ; Bd. 51) Y1 - 1998 SN - 3-519-02692-9 SP - 349 EP - 350 PB - Teubner CY - Stuttgart ER - TY - CHAP A1 - Anic, Filip A1 - Penava, Davorin A1 - Guljas, Ivica A1 - Sarhosis, Vasilis A1 - Abrahamczyk, Lars A1 - Butenweg, Christoph T1 - The Effect of Openings on Out-of-Plane Capacity of Masonry Infilled Reinforced Concrete Frames T2 - 16th European Conference on Earthquake Engineering, Thessaloniki, 18-21 June, 2018 Y1 - 2018 N1 - Paper No 10168 SP - 1 EP - 11 ER - TY - CHAP A1 - Zähl, Philipp M. A1 - Biewendt, Marcel A1 - Wolf, Martin R. A1 - Eggert, Mathias T1 - Requirements for competence developing games in the environment of SE Competence Development T2 - AKWI-Tagungsband zur 35. AKWI-Jahrestagung N2 - Many of today’s factors make software development more and more complex, such as time pressure, new technologies, IT security risks, et cetera. Thus, a good preparation of current as well as future software developers in terms of a good software engineering education becomes progressively important. As current research shows, Competence Developing Games (CDGs) and Serious Games can offer a potential solution. This paper identifies the necessary requirements for CDGs to be conducive in principle, but especially in software engineering (SE) education. For this purpose, the current state of research was summarized in the context of a literature review. Afterwards, some of the identified requirements as well as some additional requirements were evaluated by a survey in terms of subjective relevance. KW - software engineering KW - requirements KW - competence developing games KW - systematic literature review Y1 - 2022 SN - 978-3-95545-409-8 U6 - https://doi.org/10.30844/AKWI_2022_05 N1 - Tagungsband zur 35. Jahrestagung des Arbeitskreises Wirtschaftsinformatik an Hochschulen für Angewandte Wissenschaften im deutschsprachigen Raum (AKWI), 11.09. bis 13.09.2022, Hochschule für Technik und Wirtschaft Berlin (HTW Berlin) und Hochschule für Wirtschaft und Recht Berlin (HWR Berlin) SP - 73 EP - 88 PB - GITO CY - Berlin ER - TY - CHAP A1 - Butenweg, Christoph A1 - Rajan, Sreelakshmy T1 - Design and construction techniques of AAC masonry buildings in earthquakes regions T2 - 10 years Xella research in Building Materials : Symposium on the 4th and 5th of September, Potsdam 2014 Y1 - 2014 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Biele, Jens A1 - Dachwald, Bernd A1 - Grimm, Christian A1 - Lange, Caroline A1 - Ulamec, Stephan T1 - Small spacecraft for small solar system body science, planetary defence and applications T2 - IEEE Aerospace Conference 2016 N2 - Following the recent successful landings and occasional re-awakenings of PHILAE, the lander carried aboard ROSETTA to comet 67P/Churyumov-Gerasimenko, and the launch of the Mobile Asteroid Surface Scout, MASCOT, aboard the HAYABUSA2 space probe to asteroid (162173) Ryugu we present an overview of the characteristics and peculiarities of small spacecraft missions to small solar system bodies (SSSB). Their main purpose is planetary science which is transitioning from a ‘pure’ science of observation of the distant to one also supporting in-situ applications relevant for life on Earth. Here we focus on missions at the interface of SSSB science and planetary defence applications. We provide a brief overview of small spacecraft SSSB missions and on this background present recent missions, projects and related studies at the German Aerospace Center, DLR, that contribute to the worldwide planetary defence community. These range from Earth orbit technology demonstrators to active science missions in interplanetary space. We provide a summary of experience from recently flown missions with DLR participation as well as a number of studies. These include PHILAE, the lander of ESA’s ROSETTA comet rendezvous mission now on the surface of comet 67P/Churyumov-Gerasimenko, and the Mobile Asteroid Surface Scout, MASCOT, now in cruise to the ~1 km diameter C-type near-Earth asteroid (162173) Ryugu aboard the Japanese sample-return probe HAYABUSA2. We introduce the differences between the conventional methods employed in the design, integration and testing of large spacecraft and the new approaches developed by small spacecraft projects. We expect that the practical experience that can be gained from projects on extremely compressed timelines or with high-intensity operation phases on a newly explored small solar system body can contribute significantly to the study, preparation and realization of future planetary defence related missions. One is AIDA (Asteroid Impact & Deflection Assessment), a joint effort of ESA, JHU/APL, NASA, OCA and DLR, combining JHU/APL’s DART (Double Asteroid Redirection Test) and ESA’s AIM (Asteroid Impact Monitor) spacecraft in a mission towards near-Earth binary asteroid system (65803) Didymos. DLR is currently applying MASCOT heritage and lessons learned to the design of MASCOT2, a lander for the AIM mission to support a bistatic low frequency radar experiment with PHILAE/ROSETTA CONSERT heritage to explore the inner structure of Didymoon which is the designated impact target for DART. Y1 - 2016 SP - 1 EP - 20 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Bauer, Waldemar A1 - Biele, Jens A1 - Cordero, Frederico A1 - Dachwald, Bernd A1 - Koncz, Alexander A1 - Krause, Christian A1 - Mikschl, Tobias A1 - Montenegro, Sergio A1 - Quantius, Dominik A1 - Ruffer, Michael A1 - Sasaki, Kaname A1 - Schmitz, Nicole A1 - Seefeldt, Patric A1 - Tóth, Norbert A1 - Wejmo, Elisabet T1 - From Sail to Soil – Getting Sailcraft Out of the Harbour on a Visit to One of Earth’s Nearest Neighbours T2 - 4th IAA Planetary Denfense Conference - PDC 2015, 13-17 April 2015, Frascati, Roma, Italy Y1 - 2015 ER - TY - CHAP A1 - O\'Heras, Carlos A1 - Digel, Ilya A1 - Temiz Artmann, Aysegül T1 - Nanostructured carbon-based column for LPS/protein adsorption : [abstract] N2 - The absence of a general method for endotoxin removal from liquid interfaces gives an opportunity to find new methods and materials to overcome this gap. Activated nanostructured carbon is a promising material that showed good adsorption properties due to its vast pore network and high surface area. The aim of this study is to find the adsorption rates for a carboneous material produced at different temperatures, as well as to reveal possible differences between the performance of the material for each of the adsorbates used during the study (hemoglobin, serum albumin and lipopolysaccharide, LPS). KW - Kohlenstofffaser KW - Adsorption KW - Lipopolysaccharide KW - aktivierte nanostrukturierte Kohlenstofffaser KW - lipopolysaccharides KW - activated nanostructured carbon Y1 - 2009 ER - TY - CHAP A1 - ElBashir, Rasha A1 - Digel, Ilya T1 - Effect of nitric oxide gas on hydrogels : [abstract] N2 - The results support our theory that the NO gas has an influence in increasing the translational diffusion of hydrogels and it accelerates the melting process of the gels. KW - Stickstoffmonoxid KW - Hydrogel KW - nitric oxide gas KW - hydrogel Y1 - 2009 ER - TY - CHAP A1 - Götten, Falk A1 - Havermann, Marc A1 - Braun, Carsten A1 - Gomez, Francisco A1 - Bil, Cees T1 - On the Applicability of Empirical Drag Estimation Methods for Unmanned Air Vehicle Design Read More: https://arc.aiaa.org/doi/10.2514/6.2018-3192 T2 - 2018 Aviation Technology, Integration, and Operations Conference, AIAA AVIATION Forum Y1 - 2018 U6 - https://doi.org/10.2514/6.2018-3192 SN - 1533-385X N1 - AIAA 2018-3192 SP - Article 3192 ER - TY - CHAP A1 - Weiss, Christian A1 - Heslenfeld, Jonas A1 - Saewe, Jasmin Kathrin A1 - Bremen, Sebastian A1 - Häfner, Constantin Leon T1 - Investigation on the influence of powder humidity in Laser Powder Bed Fusion (LPBF) T2 - Procedia CIRP 12th CIRP Conference on Photonic Technologies [LANE 2022] N2 - In the Laser Powder Bed Fusion (LPBF) process, parts are built out of metal powder material by exposure of a laser beam. During handling operations of the powder material, several influencing factors can affect the properties of the powder material and therefore directly influence the processability during manufacturing. Contamination by moisture due to handling operations is one of the most critical aspects of powder quality. In order to investigate the influences of powder humidity on LPBF processing, four materials (AlSi10Mg, Ti6Al4V, 316L and IN718) are chosen for this study. The powder material is artificially humidified, subsequently characterized, manufactured into cubic samples in a miniaturized process chamber and analyzed for their relative density. The results indicate that the processability and reproducibility of parts made of AlSi10Mg and Ti6Al4V are susceptible to humidity, while IN718 and 316L are barely influenced. KW - LPBF KW - Additive Manufacturing KW - Powder Material KW - Humidity Y1 - 2022 U6 - https://doi.org/10.1016/j.procir.2022.08.102 SN - 2212-8271 N1 - 12th CIRP Conference on Photonic Technologies [LANE 2022], 04. September 2022 bis 08. September 2022, Fürth VL - 111 SP - 115 EP - 120 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Butenweg, Christoph ED - Kuzmanović, Vladan ED - Ignjatović, Ivan T1 - Integrated approach for monitoring and management of buildings with digital building models and modern sensor technologies T2 - Proceedings of the International Conference Civil Engineering 2021 - Achievements and Visions N2 - Nowadays modern high-performance buildings and facilities are equipped with monitoring systems and sensors to control building characteristics like energy consumption, temperature pattern and structural safety. The visualization and interpretation of sensor data is typically based on simple spreadsheets and non-standardized user-oriented solutions, which makes it difficult for building owners, facility managers and decision-makers to evaluate and understand the data. The solution of this problem in the future are integrated BIM-Sensor approaches which allow the generation of BIM models incorporating all relevant information of monitoring systems. These approaches support both the dynamic visualization of key structural performance parameters, the effective long-term management of sensor data based on BIM and provide a user-friendly interface to communicate with various stakeholders. A major benefit for the end user is the use of the BIM software architecture, which is the future standard anyway. In the following, the application of the integrated BIM-Sensor approach is illustrated for a typical industrial facility as a part of an early warning and rapid response system for earthquake events currently developed in the research project “ROBUST” with financial support by the German Federal Ministry for Economic Affairs and Energy (BMWI). Y1 - 2021 N1 - Civil Engineering 2021 – Achievements and Visions, University of Belgrade, October 25 – 26, 2021 Belgrade, Serbia SP - 67 EP - 75 PB - University of Belgrade CY - Belgrade ER - TY - CHAP A1 - Lu, S. A1 - Beyer, K. A1 - Bosiljkov, V. A1 - Butenweg, Christoph A1 - D’Ayala, D. A1 - Degee, H. A1 - Gams, M. A1 - Klouda, J. A1 - Lagomarsino, S. A1 - Penna, A. A1 - Mojsilovic, N. A1 - da Porto, F. A1 - Sorrentino, L. A1 - Vintzileou, E. ED - Modena, Claudio ED - da Porto, F. ED - Valluzzi, M.R. T1 - Next generation of Eurocode 8, masonry chapter T2 - Brick and Block Masonry Proceedings of the 16th International Brick and Block Masonry Conference, Padova, Italy, 26-30 June 2016 N2 - This paper describes the procedure on the evaluation of the masonry chapter for the next generation of Eurocode 8, the European Standard for earthquake-resistant design. In CEN, TC 250/SC8, working group WG 1 has been established to support the subcommittee on the topic of masonry on both design of new structures (EN1998-1) and assessment of existing structures (EN1998-3). The aim is to elaborate suggestions for amendments which fit the current state of the art in masonry and earthquake-resistant design. Focus will be on modelling, simplified methods, linear-analysis (q-values, overstrength-values), nonlinear procedures, out-of-plane design as well as on clearer definition of limit states. Beside these, topics related to general material properties, reinforced masonry, confined masonry, mixed structures and non-structural infills will be covered too. This paper presents the preliminary work and results up to the submission date. Y1 - 2016 SN - 978-1-138-02999-6 (Print) SN - 9781315374963 (E-Book) SP - 695 EP - 700 PB - Taylor & Francis CY - London ER - TY - CHAP A1 - Pirovano, Laura A1 - Seefeldt, Patric A1 - Dachwald, Bernd A1 - Noomen, Ron T1 - Attitude and orbital modeling of an uncontrolled solar-sail experiment in low-Earth orbit T2 - 25th International Symposium on Space Flight Dynamics ISSFD N2 - Gossamer-1 is the first project of the three-step Gossamer roadmap, the purpose of which is to develop, prove and demonstrate that solar-sail technology is a safe and reliable propulsion technique for long-lasting and high-energy missions. This paper firstly presents the structural analysis performed on the sail to understand its elastic behavior. The results are then used in attitude and orbital simulations. The model considers the main forces and torques that a satellite experiences in low-Earth orbit coupled with the sail deformation. Doing the simulations for varying initial conditions in attitude and rotation rate, the results show initial states to avoid and maximum rotation rates reached for correct and faulty deployment of the sail. Lastly comparisons with the classic flat sail model are carried out to test the hypothesis that the elastic behavior does play a role in the attitude and orbital behavior of the sail KW - Solar sail KW - Gossamer structures KW - Attitude dynamics KW - Orbital dynamics Y1 - 2015 N1 - 25th International Symposium on Space Flight Dynamics ISSFD October 19 – 23, 2015, Munich, Germany https://issfd.org/2015/ SP - 1 EP - 15 ER - TY - CHAP A1 - Maike, Müller A1 - Lenz, Laura A1 - Wolf, Martin R. T1 - Steigerung der Effektivität durch Prozessmodellierungs-Tools - Änderbarkeit und Transparenz von Prozessen am Beispiel der Business Simulation Apollo 13 T2 - Informatik 2014 N2 - Die Nutzung von Prozessmodellierungsmethoden oder - werkzeugen kann erheblichen Einfluss auf die Effektivität von Prozessen haben. Das gilt insbesondere für Situationen, in denen Personen unter Stress stehen oder ungeübt sind. In diesen Fällen geben Prozessmodelle konkrete Empfehlungen, nach denen sich die handelnden Personen richten könnten. In Experimenten mit der Business-Simulation Apollo 13 haben wir den Effekt eines Einsatzes von Prozessmodellierungsmethoden und -werkzeugen untersucht. Bereits bekannte Theorien (z.B. über geeignete Verhältnisse von Kommunikationsinhalten) konnten bestätigt werden. Darüber hinaus haben wir eine besondere Bedeutung der Übertragbarkeit von Prozessmodellen in konkrete Handlungen identifiziert. Y1 - 2014 SN - 978-3-88579-626-8 SN - 1617-5468 SP - 357 EP - 369 PB - Gesellschaft für Informatik e.V. CY - Bonn ER - TY - CHAP A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang A1 - Loeb, Horst W. A1 - Schartner, Karl-Heinz T1 - A comparison of SEP and NEP for a main belt asteroid sample return mission T2 - 7th International Symposium on Launcher Technologies, Barcelona, Spain, 02-05 April 2007 N2 - Innovative interplanetary deep space missions, like a main belt asteroid sample return mission, require ever larger velocity increments (∆V s) and thus ever more demanding propulsion capabilities. Providing much larger exhaust velocities than chemical high-thrust systems, electric low-thrust space-propulsion systems can significantly enhance or even enable such high-energy missions. In 1995, a European-Russian Joint Study Group (JSG) presented a study report on “Advanced Interplanetary Missions Using Nuclear-Electric Propulsion” (NEP). One of the investigated reference missions was a sample return (SR) from the main belt asteroid (19) Fortuna. The envisaged nuclear power plant, Topaz-25, however, could not be realized and also the worldwide developments in space reactor hardware stalled. In this paper, we investigate, whether such a mission is also feasible using a solar electric propulsion (SEP) system and compare our SEP results to corresponding NEP results. Y1 - 2007 SP - 1 EP - 10 ER - TY - CHAP A1 - Zähl, Philipp M. A1 - Theis, Sabine A1 - Wolf, Martin R. A1 - Köhler, Klemens ED - Chen, Jessie Y. C. ED - Fragomeni, Gino T1 - Teamwork in software development and what personality has to do with it - an overview T2 - Virtual, Augmented and Mixed Reality N2 - Due to the increasing complexity of software projects, software development is becoming more and more dependent on teams. The quality of this teamwork can vary depending on the team composition, as teams are always a combination of different skills and personality types. This paper aims to answer the question of how to describe a software development team and what influence the personality of the team members has on the team dynamics. For this purpose, a systematic literature review (n=48) and a literature search with the AI research assistant Elicit (n=20) were conducted. Result: A person’s personality significantly shapes his or her thinking and actions, which in turn influences his or her behavior in software development teams. It has been shown that team performance and satisfaction can be strongly influenced by personality. The quality of communication and the likelihood of conflict can also be attributed to personality. KW - Teamwork KW - Software KW - Personality KW - Performance KW - Elicit Y1 - 2023 SN - 978-3-031-35633-9 (Print) SN - 978-3-031-35634-6 (Online) U6 - https://doi.org/10.1007/978-3-031-35634-6_10 N1 - Virtual, Augmented and Mixed Reality: 15th International Conference. VAMR 2023. Held as Part of the 25th HCI International Conference. HCII 2023. Copenhagen, Denmark. July 23–28, 2023. SP - 130 EP - 153 PB - Springer CY - Cham ER - TY - CHAP A1 - Eggert, Mathias A1 - Dyong, Julian T1 - Applying process mining in small and medium sized IT enterprises – challenges and guidelines T2 - Business Process Management, 20th International Conference, BPM 2022, Proceedings N2 - Process mining gets more and more attention even outside large enterprises and can be a major benefit for small and medium sized enterprises (SMEs) to gain competitive advantages. Applying process mining is challenging, particularly for SMEs because they have less resources and process maturity. So far, IS researchers analyzed process mining challenges with a focus on larger companies. This paper investigates the application of process mining by means of a case study and sheds light into the particular challenges of an IT SME. The results reveal 13 SME process mining challenges and seven guidelines to address them. In this way, the paper contributes to the understanding of process mining application in SME and shows similarities and differences to larger companies. KW - Process mining KW - Challenges KW - Guidelines KW - SME KW - Case Study Y1 - 2022 SN - 978-3-031-16103-2 U6 - https://doi.org/10.1007/978-3-031-16103-2_11 N1 - International Conference on Business Process Management (BPM 2022), Münster, Germany, Sept. 11-16, 2022 SP - 125 EP - 142 PB - Springer CY - Cham 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 - TY - CHAP A1 - Bung, Daniel Bernhard A1 - Valero, Daniel ED - Dewals, Benjamin T1 - Image processing techniques for velocity estimation in highly aerated flows: bubble image velocimetry vs. optical flow T2 - Sustainable Hydraulics in the Era of Global Change : Proceedings of the 4th IAHR Europe Congress (Liege, Belgium, 27-29 July 2016) Y1 - 2016 SN - 978-1-138-02977-4 SN - 978-1-4987-8149-7 (eBook) U6 - https://doi.org/10.1201/b21902-31 SP - 151 EP - 157 PB - CRC Press ER - TY - CHAP A1 - Oertel, M. A1 - Bung, Daniel Bernhard ED - Crookston, B. ED - Tullis, B. T1 - Scouring processes downstream a crossbar block ramp BT - Session 3: Scour, erosion, sedimentation T2 - Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016 Y1 - 2016 SN - 978-1-884575-75-4 U6 - https://doi.org/10.15142/T3340628160853 SP - 549 EP - 559 ER - TY - CHAP A1 - Alexopoulos, Spiros A1 - Kluczka, Sven A1 - Vaeßen, Christiane A1 - Roeb, M. A1 - Neises, M. T1 - Scenario development for efficient methanol production using CO2 and solar energy T2 - Eurosun 2012 : Solar energy for a brighter future : conference proceedings : Rijeka, 18.-22.09.2012 Y1 - 2012 SP - ID 99 CY - Rijeka ER - TY - CHAP A1 - Dachwald, Bernd A1 - Kahle, Ralph A1 - Wie, Bong T1 - Head-on impact deflection of NEAs: a case study for 99942 Apophis T2 - Planetary Defense Conference 2007 N2 - Near-Earth asteroid (NEA) 99942 Apophis provides a typical example for the evolution of asteroid orbits that lead to Earth-impacts after a close Earth-encounter that results in a resonant return. Apophis will have a close Earth-encounter in 2029 with potential very close subsequent Earth-encounters (or even an impact) in 2036 or later, depending on whether it passes through one of several less than 1 km-sized gravitational keyholes during its 2029-encounter. A pre-2029 kinetic impact is a very favorable option to nudge the asteroid out of a keyhole. The highest impact velocity and thus deflection can be achieved from a trajectory that is retrograde to Apophis orbit. With a chemical or electric propulsion system, however, many gravity assists and thus a long time is required to achieve this. We show in this paper that the solar sail might be the better propulsion system for such a mission: a solar sail Kinetic Energy Impactor (KEI) spacecraft could impact Apophis from a retrograde trajectory with a very high relative velocity (75-80 km/s) during one of its perihelion passages. The spacecraft consists of a 160 m × 160 m, 168 kg solar sail assembly and a 150 kg impactor. Although conventional spacecraft can also achieve the required minimum deflection of 1 km for this approx. 320 m-sized object from a prograde trajectory, our solar sail KEI concept also allows the deflection of larger objects. For a launch in 2020, we also show that, even after Apophis has flown through one of the gravitational keyholes in 2029, the solar sail KEI concept is still feasible to prevent Apophis from impacting the Earth, but many KEIs would be required for consecutive impacts to increase the total Earth-miss distance to a safe value Y1 - 2007 N1 - Planetary Defense Conference 2007, Wahington D.C., USA, 05-08 March 2007 SP - 1 EP - 12 ER - TY - CHAP A1 - Bassam, Rasha A1 - Digel, Ilya A1 - Artmann, Gerhard T1 - Effect of nitric oxide on protein thermal stability : [abstract] N2 - As a deduction from these results, we can conclude that proteins mainly in vitro, denaturate totally at a temperature between 57°C -62°C, and they also affected by NO and different ions types. In which mainly, NO cause earlier protein denaturation, which means that, NO has a destabilizing effect on proteins, and also different ions will alter the protein denaturation in which, some ions will cause earlier protein denaturation while others not. KW - Stickstoffmonoxid KW - Proteine KW - Hämoglobin KW - nitric oxide gas KW - protein KW - hemoglobin Y1 - 2009 ER - TY - CHAP A1 - Ferrein, Alexander A1 - Maier, Christopher A1 - Mühlbacher, Clemens A1 - Niemüller, Tim A1 - Steinbauer, Gerald A1 - Vassos, Stravros T1 - Controlling logistics robots with the action-based language YAGI T2 - Intelligent Robotics and Applications: 9th International Conference, ICIRA 2016, Tokyo, Japan, August 22-24, 2016, Proceedings, Part I Y1 - 2016 SN - 978-3-319-43505-3 (Print) SN - 978-3-319-43506-0 (Online) U6 - https://doi.org/10.1007/978-3-319-43506-0_46 N1 - Series: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) VL - 9834 SP - 525 EP - 537 PB - Springer ER - TY - CHAP A1 - Braun, Carsten A1 - Boucke, Alexander A1 - Ballmann, Josef T1 - Numerical prediction of the wing deformation of a high speed transport aircraft type wind tunnel model by direct aeroelastic simulation T2 - Conference proceedings : CEAS/AIAA/DGLR International Forum on Aeroelasticity and Structural Dynamics IFASD 2005 : München, June 28 - July 1, 2005. DGLR-Bericht. 2005,04 Y1 - 2005 SN - 3-932182-43-X PB - DGLR CY - Bonn ER - TY - CHAP A1 - Niemueller, Tim A1 - Ferrein, Alexander A1 - Reuter, Sebastian A1 - Jeschke, Sabina A1 - Lakemeyer, Gerhard T1 - The RoboCup Logistics League as a Holistic Multi-Robot Smart Factory Benchmark T2 - Proceedings of the IROS 2015 Open forum on evaluation of results, replication of experiments and benchmarking in robotics research N2 - With autonomous mobile robots receiving increased attention in industrial contexts, the need for benchmarks becomes more and more an urgent matter. The RoboCup Logistics League (RCLL) is one specific industry-inspired scenario focusing on production logistics within a Smart Factory. In this paper, we describe how the RCLL allows to assess the performance of a group of robots within the scenario as a whole, focusing specifically on the coordination and cooperation strategies and the methods and components to achieve them. We report on recent efforts to analyze performance of teams in 2014 to understand the implications of the current grading scheme, and derived criteria and metrics for performance assessment based on Key Performance Indicators (KPI) adapted from classic factory evaluation. We reflect on differences and compatibility towards RoCKIn, a recent major benchmarking European project. Y1 - 2015 ER - TY - CHAP A1 - Eichenbaum, Julian A1 - Nikolovski, Gjorgji A1 - Mülhens, Leon A1 - Reke, Michael A1 - Ferrein, Alexander A1 - Scholl, Ingrid T1 - Towards a lifelong mapping approach using Lanelet 2 for autonomous open-pit mine operations T2 - 2023 IEEE 19th International Conference on Automation Science and Engineering (CASE) N2 - Autonomous agents require rich environment models for fulfilling their missions. High-definition maps are a well-established map format which allows for representing semantic information besides the usual geometric information of the environment. These are, for instance, road shapes, road markings, traffic signs or barriers. The geometric resolution of HD maps can be as precise as of centimetre level. In this paper, we report on our approach of using HD maps as a map representation for autonomous load-haul-dump vehicles in open-pit mining operations. As the mine undergoes constant change, we also need to constantly update the map. Therefore, we follow a lifelong mapping approach for updating the HD maps based on camera-based object detection and GPS data. We show our mapping algorithm based on the Lanelet 2 map format and show our integration with the navigation stack of the Robot Operating System. We present experimental results on our lifelong mapping approach from a real open-pit mine. Y1 - 2023 SN - 979-8-3503-2069-5 (Online) SN - 979-8-3503-2070-1 (Print) U6 - https://doi.org/10.1109/CASE56687.2023.10260526 N1 - 19th International Conference on Automation Science and Engineering (CASE), 26-30 August 2023, Auckland, New Zealand. PB - IEEE ER - TY - CHAP A1 - Niemueller, Tim A1 - Reuter, Sebastian A1 - Ewert, Daniel A1 - Ferrein, Alexander A1 - Jeschke, Sabina A1 - Lakemeyer, Gerhard ED - Almeida, Luis T1 - The Carologistics Approach to Cope with the Increased Complexity and New Challenges of the RoboCup Logistics League 2015 T2 - RoboCup 2015: Robot World Cup XIX Y1 - 2016 SN - 978-3-319-29339-4 U6 - https://doi.org/10.1007/978-3-319-29339-4_4 N1 - Lecture Notes in Computer Science ; 9513 SP - 47 EP - 59 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Konstantinidis, K. A1 - Kowalski, Julia A1 - Martinez, C. F. A1 - Dachwald, Bernd A1 - Ewerhart, D. A1 - Förstner, R. T1 - Some necessary technologies for in-situ astrobiology on enceladus T2 - Proceedings of the International Astronautical Congress Y1 - 2015 SN - 978-151081893-4 N1 - 6th International Astronautical Congress 2015: Space - The Gateway for Mankind's Future, IAC 2015; Jerusalem; Israel; 12 October 2015 through 16 October 2015 SP - 1354 EP - 1372 ER - TY - CHAP A1 - Dachwald, Bernd T1 - Low-Thrust Mission Analysis and Global Trajectory Optimization Using Evolutionary Neurocontrol: New Results T2 - European Workshop on Space Mission Analysis ESA/ESOC, Darmstadt, Germany 10 { 12 Dec 2007 N2 - Interplanetary trajectories for low-thrust spacecraft are often characterized by multiple revolutions around the sun. Unfortunately, the convergence of traditional trajectory optimizers that are based on numerical optimal control methods depends strongly on an adequate initial guess for the control function (if a direct method is used) or for the starting values of the adjoint vector (if an indirect method is used). Especially when many revolutions around the sun are re- quired, trajectory optimization becomes a very difficult and time-consuming task that involves a lot of experience and expert knowledge in astrodynamics and optimal control theory, because an adequate initial guess is extremely hard to find. Evolutionary neurocontrol (ENC) was proposed as a smart method for low-thrust trajectory optimization that fuses artificial neural networks and evolutionary algorithms to so-called evolutionary neurocontrollers (ENCs) [1]. Inspired by natural archetypes, ENC attacks the trajectoryoptimization problem from the perspective of artificial intelligence and machine learning, a perspective that is quite different from that of optimal control theory. Within the context of ENC, a trajectory is regarded as the result of a spacecraft steering strategy that maps permanently the actual spacecraft state and the actual target state onto the actual spacecraft control vector. This way, the problem of searching the optimal spacecraft trajectory is equivalent to the problem of searching (or "learning") the optimal spacecraft steering strategy. An artificial neural network is used to implement such a spacecraft steering strategy. It can be regarded as a parameterized function (the network function) that is defined by the internal network parameters. Therefore, each distinct set of network parameters defines a different network function and thus a different steering strategy. The problem of searching the optimal steering strategy is now equivalent to the problem of searching the optimal set of network parameters. Evolutionary algorithms that work on a population of (artificial) chromosomes are used to find the optimal network parameters, because the parameters can be easily mapped onto a chromosome. The trajectory optimization problem is solved when the optimal chromosome is found. A comparison of solar sail trajectories that have been published by others [2, 3, 4, 5] with ENC-trajectories has shown that ENCs can be successfully applied for near-globally optimal spacecraft control [1, 6] and that they are able to find trajectories that are closer to the (unknown) global optimum, because they explore the trajectory search space more exhaustively than a human expert can do. The obtained trajectories are fairly accurate with respect to the terminal constraint. If a more accurate trajectory is required, the ENC-solution can be used as an initial guess for a local trajectory optimization method. Using ENC, low-thrust trajectories can be optimized without an initial guess and without expert attendance. Here, new results for nuclear electric spacecraft and for solar sail spacecraft are presented and it will be shown that ENCs find very good trajectories even for very difficult problems. Trajectory optimization results are presented for 1. NASA's Solar Polar Imager Mission, a mission to attain a highly inclined close solar orbit with a solar sail [7] 2. a mission to de ect asteroid Apophis with a solar sail from a retrograde orbit with a very-high velocity impact [8, 9] 3. JPL's \2nd Global Trajectory Optimization Competition", a grand tour to visit four asteroids from different classes with a NEP spacecraft Y1 - 2007 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 - CHAP A1 - Valero, Daniel A1 - Vogel, Jochen A1 - Schmidt, Daniel A1 - Bung, Daniel Bernhard T1 - Three-dimensional flow structure inside the cavity of a non-aerated stepped chute T2 - 7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May Y1 - 2018 SN - 978-0-692-13277-7 U6 - https://doi.org/10.15142/T3GH17 ER - TY - CHAP A1 - Anthrakidis, Anette A1 - Rusack, Markus A1 - Schwarzer, Klemens T1 - Low effort measurement method of PTC-efficiency T2 - SolarPACES 2010 : the CSP conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France Y1 - 2010 SP - 48 EP - 49 PB - Soc. OSC CY - Saint Maur ER - TY - CHAP A1 - Dey, Thomas A1 - Elsen, Ingo A1 - Ferrein, Alexander A1 - Frauenrath, Tobias A1 - Reke, Michael A1 - Schiffer, Stefan ED - Makedon, Fillia T1 - CO2 Meter: a do-it-yourself carbon dioxide measuring device for the classroom T2 - PETRA '21: Proceedings of the 14th Pervasive Technologies Related to Assistive Environments Conference N2 - In this paper we report on CO2 Meter, a do-it-yourself carbon dioxide measuring device for the classroom. Part of the current measures for dealing with the SARS-CoV-2 pandemic is proper ventilation in indoor settings. This is especially important in schools with students coming back to the classroom even with high incidents rates. Static ventilation patterns do not consider the individual situation for a particular class. Influencing factors like the type of activity, the physical structure or the room occupancy are not incorporated. Also, existing devices are rather expensive and often provide only limited information and only locally without any networking. This leaves the potential of analysing the situation across different settings untapped. Carbon dioxide level can be used as an indicator of air quality, in general, and of aerosol load in particular. Since, according to the latest findings, SARS-CoV-2 can be transmitted primarily in the form of aerosols, carbon dioxide may be used as a proxy for the risk of a virus infection. Hence, schools could improve the indoor air quality and potentially reduce the infection risk if they actually had measuring devices available in the classroom. Our device supports schools in ventilation and it allows for collecting data over the Internet to enable a detailed data analysis and model generation. First deployments in schools at different levels were received very positively. A pilot installation with a larger data collection and analysis is underway. KW - embedded hardware KW - sensor networks KW - information systems KW - education KW - do-it-yourself Y1 - 2021 SN - 9781450387927 U6 - https://doi.org/10.1145/3453892.3462697 N1 - PETRA '21: The 14th PErvasive Technologies Related to Assistive Environments Conference Corfu Greece 29 June 2021- 2 July 2021 SP - 292 EP - 299 PB - Association for Computing Machinery CY - New York ER - TY - CHAP A1 - Gehler, M. A1 - Ober-Blöbaum, S. A1 - Dachwald, Bernd T1 - Application of discrete mechanics and optimal control to spacecraft in non-keplerian motion around small solar system bodies T2 - Procceedings of the 60th International Astronautical Congress N2 - Prolonged operations close to small solar system bodies require a sophisticated control logic to minimize propellant mass and maximize operational efficiency. A control logic based on Discrete Mechanics and Optimal Control (DMOC) is proposed and applied to both conventionally propelled and solar sail spacecraft operating at an arbitrarily shaped asteroid in the class of Itokawa. As an example, stand-off inertial hovering is considered, recently identified as a challenging part of the Marco Polo mission. The approach is easily extended to stand-off orbits. We show that DMOC is applicable to spacecraft control at small objects, in particular with regard to the fact that the changes in gravity are exploited by the algorithm to optimally control the spacecraft position. Furthermore, we provide some remarks on promising developments. KW - Spacecraft Y1 - 2009 SN - 978-161567908-9 N1 - 60th International Astronautical Congress 2009, IAC 2009; Daejeon; South Korea; 12 October 2009 through 16 October 2009 SP - 1360 EP - 1371 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Kallweit, Stephan A1 - Schleupen, Josef A1 - Dahmann, Peter A1 - Bagheri, Mohsen A1 - Engemann, Heiko T1 - Entwicklung eines Kletterroboters zur Diagnose und Instandsetzung von Windenergieanlagen (SMART) T2 - Automatisierung im Fokus von Industrie 4.0 : Tagungsband AALE 2016 ; 13. Fachkonferenz, Lübeck Y1 - 2016 SN - 978-3-8356-7312-0 N1 - AALE-Konferenz <13., 2016, Lübeck> SP - 207 EP - 212 PB - DIV Deutscher Industrieverlag GmbH CY - München ER - TY - CHAP A1 - Chajan, Eduard A1 - Schulte-Tigges, Joschua A1 - Reke, Michael A1 - Ferrein, Alexander A1 - Matheis, Dominik A1 - Walter, Thomas T1 - GPU based model-predictive path control for self-driving vehicles T2 - IEEE Intelligent Vehicles Symposium (IV) N2 - One central challenge for self-driving cars is a proper path-planning. Once a trajectory has been found, the next challenge is to accurately and safely follow the precalculated path. The model-predictive controller (MPC) is a common approach for the lateral control of autonomous vehicles. The MPC uses a vehicle dynamics model to predict the future states of the vehicle for a given prediction horizon. However, in order to achieve real-time path control, the computational load is usually large, which leads to short prediction horizons. To deal with the computational load, the control algorithm can be parallelized on the graphics processing unit (GPU). In contrast to the widely used stochastic methods, in this paper we propose a deterministic approach based on grid search. Our approach focuses on systematically discovering the search area with different levels of granularity. To achieve this, we split the optimization algorithm into multiple iterations. The best sequence of each iteration is then used as an initial solution to the next iteration. The granularity increases, resulting in smooth and predictable steering angle sequences. We present a novel GPU-based algorithm and show its accuracy and realtime abilities with a number of real-world experiments. KW - Heuristic algorithms KW - Computational modeling KW - model-predictive control KW - GPU KW - autonomous driving Y1 - 2021 SN - 978-1-7281-5394-0 U6 - https://doi.org/10.1109/IV48863.2021.9575619 N1 - 2021 IEEE Intelligent Vehicles Symposium (IV), July 11-17, 2021. Nagoya, Japan SP - 1243 EP - 1248 PB - IEEE CY - New York, NY ER - TY - CHAP A1 - Dachwald, Bernd T1 - Radiation pressure force model for an ideal laser-enhanced solar sail T2 - 4th International Symposium on Solar Sailing N2 - The concept of a laser-enhanced solar sail is introduced and the radiation pressure force model for an ideal laser-enhanced solar sail is derived. A laser-enhanced solar sail is a “traditional” solar sail that is, however, not solely propelled by solar radiation, but additionally by a laser beam that illuminates the sail. The additional laser radiation pressure increases the sail's propulsive force and can give, depending on the location of the laser source, more control authority over the direction of the solar sail’s propulsive force vector. This way, laser-enhanced solar sails may augment already existing solar sail mission concepts and make novel mission concepts feasible. Y1 - 2017 N1 - 4th International Symposium on Solar Sailing 17-20 January 2017, Kyōto, Japan SP - 1 EP - 5 ER - TY - CHAP A1 - Pham, Phu Tinh A1 - Staat, Manfred T1 - A simplification for shakedown analysis of hardening structures T2 - Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon Y1 - 2015 SP - 1 EP - 4 PB - RWTH Aachen University CY - Aachen ER - TY - CHAP A1 - Bung, Daniel Bernhard A1 - Hildebrandt, Arndt A1 - Oertel, Mario A1 - Schlenkhoff, Andreas A1 - Schlurmann, Torsten ED - McKee Smith, Jane T1 - Bore propagation over a submerged horizontal plate by physical and numerical simulation T2 - Coastal engineering 2008 : proceedings of the 31st international conference; Hamburg, Germany, 31 August - 5 September 2008 ; Vol. 4 Y1 - 2008 SN - 9814277401 ; 9789814277402 SP - 3542 EP - 3553 ER - TY - CHAP A1 - Rens, Gavin A1 - Ferrein, Alexander A1 - Poel, Etienne van der T1 - Extending DTGolog to deal with POMD-Ps T2 - Proceedings of the Nineteenth Annual Symposium of the Pattern Recognition Association of South Africa (PRASA 2008) Y1 - 2008 SP - 49 EP - 54 ER - TY - CHAP A1 - Hering, T. A1 - Ulber, Roland A1 - Tippkötter, Nils T1 - Development of a screening system for antimicrobial surfaces T2 - New frontiers of biotech-processes (Himmelfahrtstagung) : 02-04 May 2016, Rhein-Mosel-Halle, Koblenz/Germany Y1 - 2016 SP - 129 PB - DECHEMA CY - Frankfurt am Main ER - TY - CHAP A1 - Staat, Manfred A1 - Ballmann, J. T1 - Fundamental aspects of numerical methods for the propagation of multi-dimensional nonlinear waves in solids T2 - Nonlinear hyperbolic equations : theory, computations methods, and applications ; proceedings of the 2nd International Conference on Nonlinear Hyperbolic Problems, Aachen N2 - The nonlinear scalar constitutive equations of gases lead to a change in sound speed from point to point as would be found in linear inhomogeneous (and time dependent) media. The nonlinear tensor constitutive equations of solids introduce the additional local effect of solution dependent anisotropy. The speed of a wave passing through a point changes with propagation direction and its rays are inclined to the front. It is an open question whether the widely used operator splitting techniques achieve a dimensional splitting with physically reasonable results for these multi-dimensional problems. May be this is the main reason why the theoretical and numerical investigations of multi-dimensional wave propagation in nonlinear solids are so far behind gas dynamics. We hope to promote the subject a little by a discussion of some fundamental aspects of the solution of the equations of nonlinear elastodynamics. We use methods of characteristics because they only integrate mathematically exact equations which have a direct physical interpretation. KW - Nichtlineare Welle KW - Nichtlineare Gleichung KW - Festkörper KW - Elastodynamik KW - Multi-dimensional wave propagation KW - nonlinear solids KW - nonlinear tensor constitutive equation Y1 - 1989 SP - 574 EP - 588 ER - TY - CHAP A1 - Viehmann, Tarik A1 - Limpert, Nicolas A1 - Hofmann, Till A1 - Henning, Mike A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard ED - Eguchi, Amy ED - Lau, Nuno ED - Paetzel-Prüsmann, Maike ED - Wanichanon, Thanapat T1 - Winning the RoboCup logistics league with visual servoing and centralized goal reasoning T2 - RoboCup 2022: Robot World Cup XXV N2 - The RoboCup Logistics League (RCLL) is a robotics competition in a production logistics scenario in the context of a Smart Factory. In the competition, a team of three robots needs to assemble products to fulfill various orders that are requested online during the game. This year, the Carologistics team was able to win the competition with a new approach to multi-agent coordination as well as significant changes to the robot’s perception unit and a pragmatic network setup using the cellular network instead of WiFi. In this paper, we describe the major components of our approach with a focus on the changes compared to the last physical competition in 2019. Y1 - 2023 SN - 978-3-031-28468-7 (Print) SN - 978-3-031-28469-4 (Online) U6 - https://doi.org/https://doi.org/10.1007/978-3-031-28469-4_25 N1 - Robot World Cup, RoboCup 2022. 17. July 2023. Bangkok, Thailand. Part of the Lecture Notes in Computer Science book series (LNAI,volume 13561) SP - 300 EP - 312 PB - Springer CY - Cham ER - TY - CHAP A1 - Tran, Ngoc Trinh A1 - Matthies, Hermann G. A1 - Stavroulakis, Georgios Eleftherios A1 - Staat, Manfred T1 - Direct plastic structural design by chance constrained programming T2 - 6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK N2 - We propose a stochastic programming method to analyse limit and shakedown of structures under random strength with lognormal distribution. In this investigation a dual chance constrained programming algorithm is developed to calculate simultaneously both the upper and lower bounds of the plastic collapse limit or the shakedown limit. The edge-based smoothed finite element method (ES-FEM) using three-node linear triangular elements is used. Y1 - 2018 ER - TY - CHAP A1 - Dachwald, Bernd A1 - Baturkin, Volodymyr A1 - Coverstone, Victoria A1 - Diedrich, Ben A1 - Garbe, Gregory A1 - Görlich, Marianne A1 - Leipold, Manfred A1 - Lura, Franz A1 - Macdonald, Malcolm A1 - McInnes, Colin A1 - Mengali, Giovanni A1 - Quarta, Alessandro A1 - Rios-Reyes, Leonel A1 - Scheeres, Daniel J. A1 - Seboldt, Wolfgang A1 - Wie, Bong T1 - Potential effects of optical solar sail degredation on trajectory design T2 - AAS/AIAA Astrodynamics Specialist N2 - The optical properties of the thin metalized polymer films that are projected for solar sails are assumed to be affected by the erosive effects of the space environment. Their degradation behavior in the real space environment, however, is to a considerable degree indefinite, because initial ground test results are controversial and relevant inspace tests have not been made so far. The standard optical solar sail models that are currently used for trajectory design do not take optical degradation into account, hence its potential effects on trajectory design have not been investigated so far. Nevertheless, optical degradation is important for high-fidelity solar sail mission design, because it decreases both the magnitude of the solar radiation pressure force acting on the sail and also the sail control authority. Therefore, we propose a simple parametric optical solar sail degradation model that describes the variation of the sail film’s optical coefficients with time, depending on the sail film’s environmental history, i.e., the radiation dose. The primary intention of our model is not to describe the exact behavior of specific film-coating combinations in the real space environment, but to provide a more general parametric framework for describing the general optical degradation behavior of solar sails. Using our model, the effects of different optical degradation behaviors on trajectory design are investigated for various exemplary missions. Y1 - 2005 N1 - 2005 AAS/AIAA Astrodynamics Specialist Conference, 7-11.08.2005. Lake Tahoe, California https://www.space-flight.org/AAS_meetings/2005_astro/2005_astro.html SP - 1 EP - 23 ER - TY - CHAP A1 - Staat, Manfred T1 - Limit and shakedown analysis under uncertainty T2 - Proceedings International Conference on Advances in Computational Mechanics (ACOME) Y1 - 2012 N1 - International Conference on Advances in Computational Mechanics (ACOME), August 14-16, 2012, Ho Chi Minh City, Vietnam SP - 837 EP - 861 ER - TY - CHAP A1 - Nikolovski, Gjorgji A1 - Limpert, Nicolas A1 - Nessau, Hendrik A1 - Reke, Michael A1 - Ferrein, Alexander T1 - Model-predictive control with parallelised optimisation for the navigation of autonomous mining vehicles T2 - 2023 IEEE Intelligent Vehicles Symposium (IV) N2 - The work in modern open-pit and underground mines requires the transportation of large amounts of resources between fixed points. The navigation to these fixed points is a repetitive task that can be automated. The challenge in automating the navigation of vehicles commonly used in mines is the systemic properties of such vehicles. Many mining vehicles, such as the one we have used in the research for this paper, use steering systems with an articulated joint bending the vehicle’s drive axis to change its course and a hydraulic drive system to actuate axial drive components or the movements of tippers if available. To address the difficulties of controlling such a vehicle, we present a model-predictive approach for controlling the vehicle. While the control optimisation based on a parallel error minimisation of the predicted state has already been established in the past, we provide insight into the design and implementation of an MPC for an articulated mining vehicle and show the results of real-world experiments in an open-pit mine environment. KW - Mpc KW - Control KW - Path-following KW - Navigation KW - Automation Y1 - 2023 SN - 979-8-3503-4691-6 (Online) SN - 979-8-3503-4692-3 (Print) U6 - https://doi.org/10.1109/IV55152.2023.10186806 N1 - IEEE Symposium on Intelligent Vehicle, 4.-7. June 2023, Anchorage, AK, USA. PB - IEEE ER - TY - CHAP A1 - Capitain, C. A1 - Hering, T. A1 - Tippkötter, Nils A1 - Ulber, Roland T1 - Enzymatic polymerization of lignin model compounds and solubilized lignin in an aqueous ethanol extract T2 - New frontiers of biotech-processes (Himmelfahrtstagung) : 02-04 May 2016, Rhein-Mosel-Halle, Koblenz/Germany Y1 - 2016 SP - 151 EP - 152 PB - DECHEMA CY - Frankfurt am Main ER - TY - CHAP A1 - Duong, Minh Tuan A1 - Nguyen, Nhu Huynh A1 - Staat, Manfred ED - Eberhardsteiner, J. T1 - Numerical stability enhancement of modeling hyperelastic materials T2 - Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Y1 - 2012 N1 - 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012 ER - TY - CHAP A1 - Becker, Jörg A1 - Eggert, Mathias A1 - Heddier, Marcel A1 - Knackstedt, Ralf T1 - Merging Conceptual Modeling and Law for Legally Compliant Information Systems Design - A Framework-Based Research Agenda T2 - 45th Hawaii International Conference on System Sciences 2012 Y1 - 2012 SN - 978-0-7695-4525-7 U6 - https://doi.org/10.1109/HICSS.2012.428 SP - 5241 EP - 5248 ER - TY - CHAP A1 - Eichler, Fabian A1 - Skupin, Marco A1 - Thurn, Laura A1 - Kasch, Susanne A1 - Schmidt, Thomas T1 - Operating limits for beam melting of glass materials T2 - Modern Technologies in Manufacturing (MTeM 2019) N2 - Laser-based Additive Manufacturing (AM) processes for the use of metals out of the powder bed have been investigated profusely and are prevalent in industry. Although there is a broad field of application, Laser Powder Bed Fusion (LPBF), also known as Selective Laser Melting (SLM) of glass is not fully developed yet. The material properties of glass are significantly different from the investigated metallic material for LPBF so far. As such, the process cannot be transferred, and the parameter limits and the process sequence must be redefined for glass. Starting with the characterization of glass powders, a parameter field is initially confined to investigate the process parameter of different glass powder using LPBFprocess. A feasibility study is carried out to process borosilicate glass powder. The effects of process parameters on the dimensional accuracy of fabricated parts out of borosilicate and hints for the post-processing are analysed and presented in this paper. Y1 - 2019 U6 - https://doi.org/10.1051/matecconf/201929901004 N1 - MATEC Web of Conferences 299; MTeM 2019 VL - 299 IS - Article 01004 ER - TY - CHAP A1 - Ferrein, Alexander A1 - Maier, Christopher A1 - Mühlbacher, Clemens A1 - Niemueller, Tim A1 - Steinbauer, Gerald A1 - Vassos, Stravros T1 - Controlling Logistics Robots with the Action-based Language YAGI T2 - Proceedings of the 2015 IROS Workshop on Workshop on Task Planning for Intelligent Robots in Service and Manufacturing Y1 - 2015 ER - TY - CHAP A1 - Baumann, Torsten A1 - Teixeira Boura, Cristiano José A1 - Eckstein, Julian A1 - Dabrowski, Jan A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Schmitz, Stefan A1 - Zunft, Stefan T1 - Properties of bulk materials for high-temperature air-sand heat exchangers T2 - 30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 2 Y1 - 2012 SN - 978-1-61839-364-7 SP - 1270 EP - 1278 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Ferrein, Alexander A1 - Meeßen, Marcus A1 - Limpert, Nicolas A1 - Schiffer, Stefan ED - Lepuschitz, Wilfried T1 - Compiling ROS schooling curricula via contentual taxonomies T2 - Robotics in Education N2 - The Robot Operating System (ROS) is the current de-facto standard in robot middlewares. The steadily increasing size of the user base results in a greater demand for training as well. User groups range from students in academia to industry professionals with a broad spectrum of developers in between. To deliver high quality training and education to any of these audiences, educators need to tailor individual curricula for any such training. In this paper, we present an approach to ease compiling curricula for ROS trainings based on a taxonomy of the teaching contents. The instructor can select a set of dedicated learning units and the system will automatically compile the teaching material based on the dependencies of the units selected and a set of parameters for a particular training. We walk through an example training to illustrate our work. Y1 - 2021 SN - 978-3-030-67411-3 U6 - https://doi.org/10.1007/978-3-030-67411-3_5 N1 - RiE: International Conference on Robotics in Education (RiE); Advances in Intelligent Systems and Computing book series (AISC, volume 1316) SP - 49 EP - 60 PB - Springer CY - Cham ER - TY - CHAP A1 - Jung, Alexander A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - Electromechanical model of hiPSC-derived ventricular cardiomyocytes cocultured with fibroblasts T2 - 6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK N2 - The CellDrum provides an experimental setup to study the mechanical effects of fibroblasts co-cultured with hiPSC-derived ventricular cardiomyocytes. Multi-scale computational models based on the Finite Element Method are developed. Coupled electrical cardiomyocyte-fibroblast models (cell level) are embedded into reaction-diffusion equations (tissue level) which compute the propagation of the action potential in the cardiac tissue. Electromechanical coupling is realised by an excitation-contraction model (cell level) and the active stress arising during contraction is added to the passive stress in the force balance, which determines the tissue displacement (tissue level). Tissue parameters in the model can be identified experimentally to the specific sample. Y1 - 2018 ER - TY - CHAP A1 - Kahmann, Stephanie Lucina A1 - Uschok, Stephan A1 - Wegmann, Kilian A1 - Müller, Lars-P. A1 - Staat, Manfred T1 - Biomechanical multibody model with refined kinematics of the elbow T2 - 6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK N2 - The overall objective of this study is to develop a new external fixator, which closely maps the native kinematics of the elbow to decrease the joint force resulting in reduced rehabilitation time and pain. An experimental setup was designed to determine the native kinematics of the elbow during flexion of cadaveric arms. As a preliminary study, data from literature was used to modify a published biomechanical model for the calculation of the joint and muscle forces. They were compared to the original model and the effect of the kinematic refinement was evaluated. Furthermore, the obtained muscle forces were determined in order to apply them in the experimental setup. The joint forces in the modified model differed slightly from the forces in the original model. The muscle force curves changed particularly for small flexion angles but their magnitude for larger angles was consistent. Y1 - 2018 ER - TY - CHAP A1 - Hofmann, Till A1 - Mataré, Victor A1 - Schiffer, Stefan A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard T1 - Constraint-based online transformation of abstract plans into executable robot actions T2 - Proceedings of the 2018 AAAI Spring Symposium on Integrating Representation, Reasoning, Learning, and Execution for Goal Directed Autonomy Y1 - 2018 SP - 549 EP - 553 ER - TY - CHAP A1 - Stopforth, Riaan A1 - Davrajh, Shaniel A1 - Ferrein, Alexander T1 - Design considerations of the duo fugam dual rotor UAV T2 - 2017 Pattern Recognition Association of South Africa and Robotics and Mechatronics (PRASA-RobMech) Y1 - 2017 SN - 978-1-5386-2314-5 U6 - https://doi.org/10.1109/RoboMech.2017.8261115 SP - 7 EP - 13 ER - TY - CHAP A1 - Niemueller, Tim A1 - Reuter, Sebastian A1 - Ferrein, Alexander A1 - Jeschke, Sabina A1 - Lakemeyer, Gerhard ED - Almeida, Luis T1 - Evaluation of the RoboCup Logistics League and Derived Criteria for Future Competitions T2 - RoboCup 2015: Robot World Cup XIX Y1 - 2016 SN - 978-3-319-29339-4 U6 - https://doi.org/10.1007/978-3-319-29339-4_3 N1 - Lecture Notes in Computer Science ; 9513 SP - 31 EP - 43 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Bhattarai, Aroj A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - Biomechanical study of the female pelvic floor dysfunction using the finite element method T2 - Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon Y1 - 2015 SP - 1 EP - 4 PB - RWTH Aachen University CY - Aachen ER - TY - CHAP A1 - Becker, Jörg A1 - Eggert, Mathias A1 - Schwittay, Sebastian ED - Mattfeld, Dirk Christian T1 - How to Evaluate the Practical Relevance of Business Process Compliance Checking Approaches? T2 - Multikonferenz Wirtschaftsinformatik 2012 - Tagungsband der MKWI 2012 Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:084-13011115376 SP - 849 EP - 862 PB - Institut für Wirtschaftsinformatik CY - Braunschweig ER - TY - CHAP A1 - Waldmann, Christoph A1 - Vera, Jean-Pierre de A1 - Dachwald, Bernd A1 - Strasdeit, Henry A1 - Sohl, Frank A1 - Hanff, Hendrik A1 - Kowalski, Julia A1 - Heinen, Dirk A1 - Macht, Sabine A1 - Bestmann, Ulf A1 - Meckel, Sebastian A1 - Hildebrandt, Marc A1 - Funke, Oliver A1 - Gehrt, Jan-Jöran T1 - Search for life in ice-covered oceans and lakes beyond Earth T2 - 2018 IEEE/OES Autonomous Underwater Vehicle Workshop, Proceedings November 2018, Article number 8729761 N2 - The quest for life on other planets is closely connected with the search for water in liquid state. Recent discoveries of deep oceans on icy moons like Europa and Enceladus have spurred an intensive discussion about how these waters can be accessed. The challenge of this endeavor lies in the unforeseeable requirements on instrumental characteristics both with respect to the scientific and technical methods. The TRIPLE/nanoAUV initiative is aiming at developing a mission concept for exploring exo-oceans and demonstrating the achievements in an earth-analogue context, exploring the ocean under the ice shield of Antarctica and lakes like Dome-C on the Antarctic continent. KW - Planetary exploration KW - Jupiter KW - ice moons KW - underwater vehicle KW - Antarctica Y1 - 2018 U6 - https://doi.org/10.1109/AUV.2018.8729761 ER - TY - CHAP A1 - Niemueller, Tim A1 - Neumann, Tobias A1 - Henke, Christoph A1 - Schönitz, Sebastian A1 - Reuter, Sebastian A1 - Ferrein, Alexander A1 - Jeschke, Sabina A1 - Lakemeyer, Gerhard T1 - Improvements for a robust production in the RoboCup logistics league 2016 T2 - RoboCup 2016: Robot World Cup XX. RoboCup 2016. Y1 - 2017 SN - 978-3-319-68792-6 U6 - https://doi.org/10.1007/978-3-319-68792-6_49 SP - 589 EP - 600 PB - Springer CY - Cham ER - TY - CHAP A1 - Duprat, J. A1 - Dachwald, Bernd A1 - Hilchenbach, M. A1 - Engrand, Cecile A1 - Espe, C. A1 - Feldmann, M. A1 - Francke, Gero A1 - Görög, Mark A1 - Lüsing, N. A1 - Langenhorst, Falko T1 - The MARVIN project: a micrometeorite harvester in Antarctic snow T2 - 44th Lunar and Planetary Science Conference N2 - MARVIN is an automated drilling and melting probe dedicated to collect pristine interplanetary dust particles (micrometeorites) from central Antarctica snow. Y1 - 2013 N1 - 44th Lunar and Planetary Science Conference, March 18-22, 2013, The Woodlands, Texas ER - TY - CHAP A1 - Hofmann, Till A1 - Limpert, Nicolas A1 - Mataré, Victor A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard T1 - Winning the RoboCup Logistics League with Fast Navigation, Precise Manipulation, and Robust Goal Reasoning T2 - RoboCup 2019: Robot World Cup XXIII. RoboCup Y1 - 2019 SN - 978-3-030-35699-6 U6 - https://doi.org/10.1007/978-3-030-35699-6_41 N1 - Lecture Notes in Computer Science, vol 11531 SP - 504 EP - 516 PB - Springer CY - Cham ER - TY - CHAP A1 - Kasch, Susanne A1 - Schmidt, Thomas A1 - Eichler, Fabian A1 - Thurn, Laura A1 - Jahn, Simon A1 - Bremen, Sebastian T1 - Solution approaches and process concepts for powder bed-based melting of glass T2 - Industrializing Additive Manufacturing. Proceedings of AMPA2020 N2 - In the study, the process chain of additive manufacturing by means of powder bed fusion will be presented based on the material glass. In order to reliably process components additively, new concepts with different solutions were developed and investigated. Compared to established metallic materials, the properties of glass materials differ significantly. Therefore, the process control was adapted to the material glass in the investigations. With extensive parameter studies based on various glass powders such as borosilicate glass and quartz glass, scientifically proven results on powder bed fusion of glass are presented. Based on the determination of the particle properties with different methods, extensive investigations are made regarding the melting behavior of glass by means of laser beams. Furthermore, the experimental setup was steadily expanded. In addition to the integration of coaxial temperature measurement and regulation, preheating of the building platform is of major importance. This offers the possibility to perform 3D printing at the transformation temperatures of the glass materials. To improve the component’s properties, the influence of a subsequent heat treatment was also investigated. The experience gained was incorporated into a new experimental system, which allows a much better exploration of the 3D printing of glass. Currently, studies are being conducted to improve surface texture, building accuracy, and geometrical capabilities using three-dimensional specimen. The contribution shows the development of research in the field of 3D printing of glass, gives an insight into the machine and process engineering as well as an outlook on the possibilities and applications. KW - Glass powder KW - Laser processing KW - Additive manufacturing KW - Melting KW - L-PBF Y1 - 2020 SN - 978-3-030-54333-4 (Print) SN - 978-3-030-54334-1 (Online) U6 - https://doi.org/10.1007/978-3-030-54334-1_7 N1 - International Conference on Additive Manufacturing in Products and Applications. 01.-03. September 2020. Zurich, Switzerland SP - 82 EP - 95 PB - Springer CY - Cham ER - TY - CHAP A1 - Valero, Daniel A1 - Bung, Daniel Bernhard A1 - Oertel, M. ED - Dewals, Benjamin T1 - Turbulent dispersion in bounded horizontal jets : RANS capabilities and physical modeling comparison T2 - Sustainable Hydraulics in the Era of Global Change : Proceedings of the 4th IAHR Europe Congress (Liege, Belgium, 27-29 July 2016) Y1 - 2016 SN - 978-1-138-02977-4 SN - 978-1-4987-8149-7 (eBook) U6 - https://doi.org/10.1201/b21902-13 SP - 49 EP - 55 PB - CRC Press ER - TY - CHAP A1 - Engel, M. A1 - Thieringer, J. A1 - Tippkötter, Nils T1 - Microbial electrosynthesis for sustainable biobutanol production T2 - New frontiers of biotech-processes (Himmelfahrtstagung) : 02-04 May 2016, Rhein-Mosel-Halle, Koblenz/Germany Y1 - 2016 SP - 77 EP - 78 PB - DECHEMA CY - Frankfurt am Main ER - TY - CHAP A1 - Finger, Felix A1 - Khalsa, R. A1 - Kreyer, Jörg A1 - Mayntz, Joscha A1 - Braun, Carsten A1 - Dahmann, Peter A1 - Esch, Thomas A1 - Kemper, Hans A1 - Schmitz, O. A1 - Bragard, Michael T1 - An approach to propulsion system modelling for the conceptual design of hybrid-electric general aviation aircraft T2 - Deutscher Luft- und Raumfahrtkongress 2019, 30.9.-2.10.2019, Darmstadt N2 - In this paper, an approach to propulsion system modelling for hybrid-electric general aviation aircraft is presented. Because the focus is on general aviation aircraft, only combinations of electric motors and reciprocating combustion engines are explored. Gas turbine hybrids will not be considered. The level of the component's models is appropriate for the conceptual design stage. They are simple and adaptable, so that a wide range of designs with morphologically different propulsive system architectures can be quickly compared. Modelling strategies for both mass and efficiency of each part of the propulsion system (engine, motor, battery and propeller) will be presented. Y1 - 2019 ER - TY - CHAP A1 - Göttsche, Joachim A1 - Hinsch, Andreas A1 - Wittwer, Volker ED - Hugo-Le Goff, Anne T1 - Electrochromic and optical properties of mixed WO3-TiO2 thin films produced by sputtering and the sol-gel technique T2 - Optical materials technology for energy efficiency and solar energy conversion XI: chromogenics for smart windows : 19 and 21 May 1992, Toulouse-Labège. (SPIE proceedings series. 1728) Y1 - 1992 SN - 0-8194-0901-4 SP - 13 EP - 25 PB - SPIE CY - Bellingham, Wash. ER - TY - CHAP A1 - Bäcker, Matthias A1 - Koch, C. A1 - Geiger, F. A1 - Eber, F. A1 - Gliemann, H. A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - A New Class of Biosensors Based on Tobacco Mosaic Virus and Coat Proteins as Enzyme Nanocarrier T2 - Procedia Engineering Y1 - 2016 U6 - https://doi.org/10.1016/j.proeng.2016.11.228 SN - 1877-7058 N1 - Proceedings of the 30th anniversary Eurosensors Conference – Eurosensors 2016, 4-7. Sepember 2016, Budapest, Hungary VL - Vol. 168 SP - 618 EP - 621 ER - TY - CHAP A1 - Ritz, Thomas A1 - Fuchs, Britta ED - Breitner, Michael T1 - Kosten-Nutzen-Bewertungen bei mobilen Anwendungen T2 - Mobile und Ubiquitäre Informationssysteme - Technologien, Prozesse, Marktfahigkeit. Proceedings zur 3. Konferenz Mobile und Ubiquitäre Informationssysteme (MMS 2008) 26. - 28. Februar 2008, München, Germany. - (GI-Edition : Proceedings ; 123) Breitner, Michael H. [Hrsg.] Y1 - 2008 SN - 978-3-88579-217-8 SP - 164 EP - 177 PB - Ges. für Informatik CY - Bonn ER - TY - CHAP A1 - Wu, Chunsheng A1 - Poghossian, Arshak A1 - Werner, Frederik A1 - Bronder, Thomas A1 - Bäcker, Matthias A1 - Wang, Ping A1 - Schöning, Michael Josef T1 - An application of a scanning light-addressable potentiometric sensor for label-free DNA detection T2 - 11. Dresdner Sensor-Symposium : 9.-11.12.2013 Y1 - 2013 SN - 978-3-9813484-5-3 SP - 164 EP - 168 ER - TY - CHAP A1 - Ferrein, Alexander A1 - Niemüller, Tim A1 - Schiffer, Stefan A1 - Lakemeyer, Gerhard ED - Boots, Byron T1 - Lessons learnt from developing the embodied AI platform CAESAR for domestic service robotics T2 - Designing intelligent robots : reintegrating AI II ; papers from the AAAI spring symposium ; [held March 25 - 27, 2013 in Palo Alto, California, USA, on the campus of Stanford University]. (Technical Report / Association for the Advancement of Artificial Intelligence ; 2013,4) Y1 - 2013 SN - 9781577356011 SP - 21 EP - 26 ER - TY - CHAP A1 - Leingartner, Max A1 - Maurer, Johannes A1 - Steinbauer, Gerald A1 - Ferrein, Alexander T1 - Evaluation of sensors and mapping approaches for disasters in tunnels T2 - IEEE International Symposium on Safety, Security, and Rescue Robotics : SSRR : 21-26 Oct. 2013, Linkoping, Sweden Y1 - 2013 SN - 978-1-4799-0879-0 SP - 1 EP - 7 ER - TY - CHAP A1 - Niemüller, Tim A1 - Ewert, Daniel A1 - Reuter, Sebastian A1 - Ferrein, Alexander A1 - Jeschke, Sabina A1 - Lakemeyer, Gerhard T1 - The Carologistics RoboCup Logistics Team 2013 T2 - RoboCup 2013 : Eindhoven Y1 - 2013 SP - 1 EP - 8 ER - TY - CHAP A1 - Ferrein, Alexander A1 - Lakemeyer, Gerhard A1 - Schiffer, Stefan T1 - AllemaniACs@ home 2006 team description Y1 - 2006 SP - 1 EP - 6 ER - TY - CHAP A1 - Heuermann, Holger A1 - Sadeghfam, Arash A1 - Finger, Torsten T1 - Alternative ignition system based on microwave plasma T2 - Advanced ignition systems for gasoline engines : [Vorträge der 1st International Conference Advanced Ignition Systems for Gasoline Engines - 1. Internationale Tagung Zündsysteme für Ottomotoren, 12.-13. November 2012, Berlin] Y1 - 2013 SN - 9783816931904 SP - 95 EP - 103 PB - Expert-Verl. CY - Renningen ER -