TY - JOUR A1 - Thielemann, Frank A1 - Kriegesmann, Bernd A1 - Schaffner, M. T1 - Mit vereinten Kräften die Wettbewerbsfähigkeit steigern - Kooperation als Antwort auf den In­novationsdruck . Kriegesmann, B.; Thielemann, F.; Schaffner, M. JF - Der Druckspiegel. 50 (1995), H. 10 Y1 - 1995 SN - 0012-6500 SP - 931 EP - 935 ER - TY - JOUR A1 - Förster, Arnold A1 - Zamdmer, N. A1 - Hu, Qing A1 - Verghese, S. T1 - Mode-Discriminating Photoconductor and Coplanar Wave-Guide Circuits for Picosecond Sampling. Zamdmer, N.; Hu, Qing ; Verghese, S. ; Förster, A. JF - Applied Physics Letters. 74 (1999), H. 7 Y1 - 1999 SN - 1077-3118 SP - 1039 EP - 1041 ER - TY - CHAP A1 - Schwager, Christian A1 - Angele, Florian A1 - Schwarzbözl, Peter A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Model predictive assistance for operational decision making in molten salt receiver systems T2 - SolarPACES: Solar Power & Chemical Energy Systems N2 - Despite the challenges of pioneering molten salt towers (MST), it remains the leading technology in central receiver power plants today, thanks to cost effective storage integration and high cost reduction potential. The limited controllability in volatile solar conditions can cause significant losses, which are difficult to estimate without comprehensive modeling [1]. This paper presents a Methodology to generate predictions of the dynamic behavior of the receiver system as part of an operating assistance system (OAS). Based on this, it delivers proposals if and when to drain and refill the receiver during a cloudy period in order maximize the net yield and quantifies the amount of net electricity gained by this. After prior analysis with a detailed dynamic two-phase model of the entire receiver system, two different reduced modeling approaches where developed and implemented in the OAS. A tailored decision algorithm utilizes both models to deliver the desired predictions efficiently and with appropriate accuracy. KW - Power plants KW - Associated liquids KW - Decision theory KW - Electrochemistry Y1 - 2023 SN - 978-0-7354-4623-6 U6 - http://dx.doi.org/10.1063/5.0151514 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - 27th International Conference on Concentrating Solar Power and Chemical Energy Systems 27 September–1 October 2021 Online IS - 2815 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - JOUR A1 - Rieke, Christian A1 - Stollenwerk, Dominik A1 - Dahmen, Markus A1 - Pieper, Martin T1 - Modeling and optimization of a biogas plant for a demand-driven energy supply JF - Energy N2 - Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process. This paper provides a new model of a biogas plant, which is as accurate as the standard ADM1 model. The advantage compared to ADM1 is that it is based on only four parameters compared to 28. Applying this model, an optimization was installed, which allows a demand-driven supply by biogas plants. Finally the results are confirmed by several experiments and measurements with a real test plant. Y1 - 2018 U6 - http://dx.doi.org/10.1016/j.energy.2017.12.073 SN - 0360-5442 VL - 145 SP - 657 EP - 664 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Rendon, Carlos A1 - Schwager, Christian A1 - Ghiasi, Mona A1 - Schmitz, Pascal A1 - Bohang, Fakhri A1 - Caminos, Ricardo Alexander Chico A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Modeling and upscaling of a pilot bayonettube reactor for indirect solar mixed methane reforming T2 - AIP Conference Proceedings Y1 - 2020 U6 - http://dx.doi.org/10.1063/5.0029974 IS - 2303 SP - 170012-1 EP - 170012-9 ER - TY - JOUR A1 - Vogt, Christian A1 - Iwanowski-Strahser, Katha A1 - Marquart, Gabriele A1 - Arnold, Juliane A1 - Mottaghy, Darius A1 - Pechnig, Renate A1 - Gnjezda, Daniel A1 - Clauser, Christoph T1 - Modeling contribution to risk assessment of thermal production power for geothermal reservoirs JF - Renewable Energy Y1 - 2013 U6 - http://dx.doi.org/10.1016/j.renene.2012.11.026 SN - 0960-1481 VL - 53 SP - 230 EP - 241 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Zahra, Mahdi A1 - Phani Srujan, Merige A1 - Caminos, Ricardo Alexander Chico A1 - Schmitz, Pascal A1 - Herrmann, Ulf A1 - Teixeira Boura, Cristiano José A1 - Schmitz, Mark A1 - Gielen, Hans A1 - Gedle, Yibekal A1 - Dersch, Jürgen T1 - Modeling the thermal behavior of solar salt in electrical resistance heaters for the application in PV-CSP hybrid power plants T2 - SOLARPACES 2020 N2 - Concentrated Solar Power (CSP) systems are able to store energy cost-effectively in their integrated thermal energy storage (TES). By intelligently combining Photovoltaics (PV) systems with CSP, a further cost reduction of solar power plants is expected, as well as an increase in dispatchability and flexibility of power generation. PV-powered Resistance Heaters (RH) can be deployed to raise the temperature of the molten salt hot storage from 385 °C up to 565 °C in a Parabolic Trough Collector (PTC) plant. To avoid freezing and decomposition of molten salt, the temperature distribution in the electrical resistance heater is investigated in the present study. For this purpose, a RH has been modeled and CFD simulations have been performed. The simulation results show that the hottest regions occur on the electric rod surface behind the last baffle. A technical optimization was performed by adjusting three parameters: Shell-baffle clearance, electric rod-baffle clearance and number of baffles. After the technical optimization was carried out, the temperature difference between the maximum temperature and the average outlet temperature of the salt is within the acceptable limits, thus critical salt decomposition has been avoided. Additionally, the CFD simulations results were analyzed and compared with results obtained with a one-dimensional model in Modelica. KW - Solar thermal technologies KW - Hybrid energy system KW - Concentrated solar power KW - Energy storage KW - Photovoltaics Y1 - 2022 SN - 978-0-7354-4195-8 U6 - http://dx.doi.org/10.1063/5.0086268 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - 26th International Conference on Concentrating Solar Power and Chemical Energy Systems 28 September–2 October 2020 Freiburg, Germany IS - 2445 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - BOOK A1 - Meißen, Ralf A1 - Hotfilter, Josef T1 - Modell einer Einrichtung zur Positionierung von kugelförmigen Brennelementen nach einer Bohrung mit berührungsloser fluidischer Abtastung / Josef Hotfilter ; Ralf Meißen Y1 - 1972 N1 - Kernforschungsanlage : Berichte der ... ; 898 PB - Kernforschungsanlage CY - Jülich ER - TY - CHAP A1 - Rosin, Julia A1 - Kubalski, Thomas A1 - Butenweg, Christoph T1 - Modellierung eines basisisolierten, zylindrischen Flüssigkeitstanks aus Stahl T2 - 13. D-A-CH Tagung für Erdbebeningenieurwesen und Baudynamik (D-A-CH 2013) : 29.-30. August 2013, Wien, Österreich Y1 - 2013 SP - 1 EP - 10 ER - TY - JOUR A1 - Kubalski, Thomas A1 - Butenweg, Christoph T1 - Modelling strategies for horizontally loaded infill masonry T1 - Modellierungsansätze für horizontal beanspruchtes Ausfachungsmauerwerk JF - Mauerwerk : European journal of masonry Y1 - 2015 U6 - http://dx.doi.org/10.1002/dama.201500675 VL - Volume 19 IS - Issue 5 SP - 363 EP - 369 PB - Wiley CY - Weinheim ER - TY - CHAP A1 - Mertens, Alexander A1 - Brauner, Philipp A1 - Baier, Ralph A1 - Brillowski, Florian A1 - Dammers, Hannah A1 - van Dyck, Marc A1 - Kong, Iris A1 - Königs, Peter A1 - Kordtomeikel, Frauke A1 - Liehner, Gian Luca A1 - Pütz, Sebastian A1 - Rodermann, Niklas A1 - Schaar, Anne Kathrin A1 - Steuer-Dankert, Linda A1 - Vervier, Luisa A1 - Wlecke, Shari A1 - Gries, Thomas A1 - Leicht-Scholten, Carmen A1 - Nagel, Saskia K. A1 - Piller, Frank T. A1 - Schuh, Günther A1 - Ziefle, Martina A1 - Nitsch, Verena ED - Michael, Judith ED - Pfeiffer, Jérôme ED - Wortmann, Andreas T1 - Modelling Human Factors in Cyber Physical Production Systems by the Integration of Human Digital Shadows T2 - Modellierung 2022 Satellite Events N2 - The future of industrial manufacturing and production will increasingly manifest in the form of cyber-physical production systems. Here, Digital Shadows will act as mediators between the physical and digital world to model and operationalize the interactions and relationships between different entities in production systems. Until now, the associated concepts have been primarily pursued and implemented from a technocentric perspective, in which human actors play a subordinate role, if they are considered at all. This paper outlines an anthropocentric approach that explicitly considers the characteristics, behavior, and traits and states of human actors in socio-technical production systems. For this purpose, we discuss the potentials and the expected challenges and threats of creating and using Human Digital Shadows in production. KW - human digital shadow KW - cyber physical production system KW - human factors Y1 - 2022 U6 - http://dx.doi.org/10.18420/modellierung2022ws-018 SP - 147 EP - 149 PB - GI Gesellschaft für Informatik CY - Bonn ER - TY - JOUR A1 - Mistler, Michael A1 - Butenweg, Christoph A1 - Meskouris, Konstantin T1 - Modelling methods of historic masonry buildings under seismic excitation JF - Journal of seismology Y1 - 2006 U6 - http://dx.doi.org/10.1007/s10950-006-9033-z SN - 1383-4649 (Print) ; 1573-157X (E-Journal) VL - Volume 10 IS - No. 4 SP - 497 EP - 510 ER - TY - CHAP A1 - Kalker, Ines A1 - Neumann, M. A1 - Butenweg, Christoph A1 - Holler, Stefan T1 - Modelling of textile strengthened masonry T2 - Proceedings of the Tenth International Conference on Civil, Structural and Environmental Engineering Computing : [Rome, Italy, 30. August - 2. September 2005] / ed. by B. H. V. Topping Y1 - 2005 SN - 1-905088-00-0 U6 - http://dx.doi.org/10.4203/ccp.81.184 SP - 447 EP - 448 PB - Civil-Comp Press CY - Stirling ER - TY - JOUR A1 - Förster, Arnold A1 - Zettler, J.-T. A1 - Mikkelsen, H. A1 - Leo, K. T1 - Modulated ellipsometric measurements and transfer-matrix calculation of the field-dependent dielectric function of a multiple quantum well / J.-Th. Zettler ; H. Mikkelsen ; K. Leo ... A. Förster JF - Physical Review B . 46 (1992), H. 24 Y1 - 1992 SN - 0163-1829 N1 - 2. ISSN: 1098-0121 ; ISSN der E-Ausg.: 1095-3795 SP - 15955 EP - 15962 ER - TY - CHAP A1 - Küppers, Christine A1 - Groebel, Simone A1 - Kuperjans, Isabel A1 - Dielmann, Klaus-Peter T1 - Molekulargenetische Analysen zur Optimierung der Biogasgewinnung T2 - Biogas 2011 : 4. Innovationskongress ; Effizienzsteigerung von Biogasanlagen ; Vorstellung der 17 besten Biogas-Innovationen der letzten 12 Monate ; 12. - 13. Mai 2011, im ZUK der Deutschen Bundesstiftung Umwelt ; Tagungsband Y1 - 2011 SN - 978-3-9813776-1-3 SP - 45 EP - 48 PB - Profair Consult+Project CY - Hildesheim ER - TY - JOUR A1 - Rossi, Leonardo A1 - Winands, Mark H. M. A1 - Butenweg, Christoph ED - Zhang, Jessica T1 - Monte Carlo Tree Search as an intelligent search tool in structural design problems JF - Engineering with Computers : An International Journal for Simulation-Based Engineering N2 - Monte Carlo Tree Search (MCTS) is a search technique that in the last decade emerged as a major breakthrough for Artificial Intelligence applications regarding board- and video-games. In 2016, AlphaGo, an MCTS-based software agent, outperformed the human world champion of the board game Go. This game was for long considered almost infeasible for machines, due to its immense search space and the need for a long-term strategy. Since this historical success, MCTS is considered as an effective new approach for many other scientific and technical problems. Interestingly, civil structural engineering, as a discipline, offers many tasks whose solution may benefit from intelligent search and in particular from adopting MCTS as a search tool. In this work, we show how MCTS can be adapted to search for suitable solutions of a structural engineering design problem. The problem consists of choosing the load-bearing elements in a reference reinforced concrete structure, so to achieve a set of specific dynamic characteristics. In the paper, we report the results obtained by applying both a plain and a hybrid version of single-agent MCTS. The hybrid approach consists of an integration of both MCTS and classic Genetic Algorithm (GA), the latter also serving as a term of comparison for the results. The study’s outcomes may open new perspectives for the adoption of MCTS as a design tool for civil engineers. KW - Monte Carlo Tree Search KW - Structural design KW - Artificial intelligence KW - Civil engineering KW - Genetic algorithm Y1 - 2022 U6 - http://dx.doi.org/10.1007/s00366-021-01338-2 SN - 1435-5663 SN - 0177-0667 VL - 38 IS - 4 SP - 3219 EP - 3236 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Förster, Arnold A1 - Tillmann, K. A1 - Gerthsen, D. T1 - Morphological transformations of MBE-grown In0.6Ga0.4As island on GaAs(001) substrates / K. Tillmann ; D. Gerthsen ; P. Pfundstein ; A. Förster ... JF - Microscopy of semiconducting materials 1995 : proceedings of the Institute of Physics Conference held at Oxford University, 20 - 23 March 1995 / Ed. by A G Cullis ... - (Conference series / Institute of Physics ; 146) Y1 - 1995 SN - 0-7503-0347-6 N1 - MSM <9, 1995, Oxford> ; Institut of Physics SP - 195 EP - ff. PB - Institute of Physics CY - Bristol [u.a.] ER - TY - CHAP A1 - Rajan, Sreelakshmy A1 - Kubalski, Thomas A1 - Altay, Okyay A1 - Dalguer, Luis A A1 - Butenweg, Christoph T1 - Multi-dimensional fragility analysis of a RC building with components using response surface method T2 - 24th International Conference on Structural Mechanics in Reactor Technology, Busan, Korea, 20-25 August, 2017 N2 - Conventional fragility curves describe the vulnerability of the main structure under external hazards. However, in complex structures such as nuclear power plants, the safety or the risk depends also on the components associated with a system. The classical fault tree analysis gives an overall view of the failure and contains several subsystems to the main event, however, the interactions in the subsystems are not well represented. In order to represent the interaction of the components, a method suggested by Cimellaro et al. (2006) using multidimensional performance limit state functions to obtain the system fragility curves is adopted. This approach gives the possibility of deriving the cumulative fragility taking into account the interaction of the response of different components. In this paper, this approach is used to evaluate seismic risk of a representative electrical building infrastructure, including the component, of a nuclear power plant. A simplified model of the structure, with nonlinear material behavior is employed for the analysis in Abaqus©. The input variables considered are the material parameters, boundary conditions and the seismic input. The variability of the seismic input is obtained from selected ground motion time histories of spectrum compatible synthetic ccelerograms. Unlike the usual Monte Carlo methods used for the probabilistic analysis of the structure, a computationally effective response surface method is used. This method reduces the computational effort of the calculations by reducing the required number of samples. Y1 - 2017 SN - 9781510856776 SP - 3126 EP - 3135 PB - International Assn for Structural Mechanics in Reactor Technology (IASMiRT) CY - Raleigh, USA ER - TY - JOUR A1 - Göttsche, Joachim A1 - Alexopoulos, Spiros A1 - Dümmler, Andreas A1 - Maddineni, S. K. T1 - Multi-Mirror Array Calculations With Optical Error N2 - The optical performance of a 2-axis solar concentrator was simulated with the COMSOL Multiphysics® software. The concentrator consists of a mirror array, which was created using the application builder. The mirror facets are preconfigured to form a focal point. During tracking all mirrors are moved simultaneously in a coupled mode by 2 motors in two axes, in order to keep the system in focus with the moving sun. Optical errors on each reflecting surface were implemented in combination with the solar angular cone of ± 4.65 mrad. As a result, the intercept factor of solar radiation that is available to the receiver was calculated as a function of the transversal and longitudinal angles of incidence. In addition, the intensity distribution on the receiver plane was calculated as a function of the incidence angles. KW - solar process heat KW - concentrating collector KW - raytracing KW - point-focussing system Y1 - 2019 SP - 1 EP - 6 ER - TY - CHAP A1 - Feldhusen, Jörg A1 - Brezing, Alexander Nikolaus A1 - Pütz, Claus A1 - Wählisch, Georg T1 - Multi-system CAD-teaching in large classes T2 - When design education and design research meet : proceedings of the 12th International Conference on Engineering and Product Design Education, Norwegian University of Science and Technology (NTNU) Trondheim, Norway, 2nd - 3rd September 2010 ; [E&PDE] Y1 - 2010 SN - 978-1-904670-19-3 SP - 204 EP - 209 PB - Design Society CY - Glasgow ER -