@inproceedings{MichelRosinButenwegetal.2020, author = {Michel, Philipp and Rosin, Julia and Butenweg, Christoph and Klinkel, Sven}, title = {Soil-dependent earthquake spectra in the analysis of liquid-storage-tanks on compliant soil}, series = {Seismic design of industrial facilities 2020: proceedings of the 2nd International Conference on Seismic Design of Industrial Facilities (SeDIF-Conference)}, booktitle = {Seismic design of industrial facilities 2020: proceedings of the 2nd International Conference on Seismic Design of Industrial Facilities (SeDIF-Conference)}, isbn = {978-3-86359-729-0}, pages = {245 -- 254}, year = {2020}, language = {en} } @inproceedings{SildatkeKarwanniKraftetal.2020, author = {Sildatke, Michael and Karwanni, Hendrik and Kraft, Bodo and Schmidts, Oliver and Z{\"u}ndorf, Albert}, title = {Automated Software Quality Monitoring in Research Collaboration Projects}, series = {ICSEW'20: Proceedings of the IEEE/ACM 42nd International Conference on Software Engineering Workshops}, booktitle = {ICSEW'20: Proceedings of the IEEE/ACM 42nd International Conference on Software Engineering Workshops}, doi = {10.1145/3387940.3391478}, pages = {603 -- 610}, year = {2020}, language = {en} } @article{ButenwegRosinHoller2017, author = {Butenweg, Christoph and Rosin, Julia and Holler, Stefan}, title = {Analysis of cylindrical granular material silos under seismic excitation}, series = {Buildings}, volume = {7}, journal = {Buildings}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2075-5309}, doi = {10.3390/buildings7030061}, pages = {1 -- 12}, year = {2017}, abstract = {Silos generally work as storage structures between supply and demand for various goods, and their structural safety has long been of interest to the civil engineering profession. This is especially true for dynamically loaded silos, e.g., in case of seismic excitation. Particularly thin-walled cylindrical silos are highly vulnerable to seismic induced pressures, which can cause critical buckling phenomena of the silo shell. The analysis of silos can be carried out in two different ways. In the first, the seismic loading is modeled through statically equivalent loads acting on the shell. Alternatively, a time history analysis might be carried out, in which nonlinear phenomena due to the filling as well as the interaction between the shell and the granular material are taken into account. The paper presents a comparison of these approaches. The model used for the nonlinear time history analysis considers the granular material by means of the intergranular strain approach for hypoplasticity theory. The interaction effects between the granular material and the shell is represented by contact elements. Additionally, soil-structure interaction effects are taken into account.}, language = {en} } @inproceedings{KubalskiMarinkovićButenweg2016, author = {Kubalski, T. and Marinković, Marko and Butenweg, Christoph}, title = {Numerical investigation of masonry infilled R.C. frames}, series = {Brick and Block Masonry. Proceedings of the 16th International Brick and Block Masonry Conference, Padova, Italy, 26-30 June 2016}, booktitle = {Brick and Block Masonry. Proceedings of the 16th International Brick and Block Masonry Conference, Padova, Italy, 26-30 June 2016}, editor = {Modena, Claudio}, publisher = {CRC Press}, address = {Leiden}, isbn = {9781315374963}, pages = {1219 -- 1226}, year = {2016}, language = {en} } @inproceedings{ButenwegMarinkovic2018, author = {Butenweg, Christoph and Marinkovic, Marko}, title = {Damage reduction system for masonry infill walls under seismic loading}, series = {ce/papers}, volume = {2}, booktitle = {ce/papers}, number = {4}, publisher = {Ernst \& Sohn Verlag}, address = {Berlin}, doi = {10.1002/cepa.863}, pages = {267 -- 273}, year = {2018}, abstract = {Reinforced concrete (RC) frames with masonry infills are frequently used in seismic regions all over the world. Generally masonry infills are considered as nonstructural elements and thus are typically neglected in the design process. However, the observations made after strong earthquakes have shown that masonry infills can modify the dynamic behavior of the structure significantly. The consequences were total collapses of buildings and loss of human lives. This paper presents the new system INODIS (Innovative Decoupled Infill System) developed within the European research project INSYSME (Innovative Systems for Earthquake Resistant Masonry Enclosures in RC Buildings). INODIS decouples the frame and the masonry infill by means of special U-shaped rubbers placed in between frame and infill. The effectiveness of the system was investigated by means of full scale tests on RC frames with masonry infills subjected to in-plane and out-of-plane loading. Furthermore small specimen tests were conducted to determine material characteristics of the components and the resistances of the connections. Finally, a micromodel was developed to simulate the in-plane behavior of RC frames infilled with AAC blocks with and without installation of the INODIS system.}, language = {en} } @inproceedings{RajanHoltschoppenDalgueretal.2016, author = {Rajan, Sreelakshmy and Holtschoppen, B. and Dalguer, L. A. and Klinkel, S. and Butenweg, Christoph}, title = {Seismic fragility analysis of a non-conventional reinforced concrete structure considering different uncertainties}, series = {Proceedings of ISMA2016, International Conference on Noise and Vibration Engineering/USD2016, International Conference on Uncertainty in Structural Dynamics, / ISMA 2016, USD 2016}, booktitle = {Proceedings of ISMA2016, International Conference on Noise and Vibration Engineering/USD2016, International Conference on Uncertainty in Structural Dynamics, / ISMA 2016, USD 2016}, editor = {Sas, P.}, publisher = {KU Leuven}, address = {Leuven}, pages = {4213 -- 4225}, year = {2016}, language = {en} } @inproceedings{RajanButenwegDalgueretal.2017, author = {Rajan, S. and Butenweg, Christoph and Dalguer, L. A. and An, J. H. and Renault, P. and Klinkel, S.}, title = {Fragility curves for a three-storey reinforced concrete test structure of the international benchmark SMART 2013}, series = {16th World Conference on Earthquake, 16WCEE 2017 Santiago Chile, January 9th to 13th 2017}, booktitle = {16th World Conference on Earthquake, 16WCEE 2017 Santiago Chile, January 9th to 13th 2017}, publisher = {Chilean Association on Seismology and Earthquake Engineering (ACHISINA)}, year = {2017}, language = {en} } @inproceedings{KernImaniVashianiTimmermanns2021, author = {Kern, Alexander and Imani Vashiani, Anahita and Timmermanns, Tobias}, title = {Threat for human beings due to touch voltages and body currents caused by direct lightning strikes in case of non-isolated lightning protection systems using natural components}, series = {35th International Conference on Lightning Protection (ICLP) and XVI International Symposium on Lightning Protection (SIPDA)}, booktitle = {35th International Conference on Lightning Protection (ICLP) and XVI International Symposium on Lightning Protection (SIPDA)}, publisher = {IEEE}, isbn = {978-1-6654-2346-5}, doi = {10.1109/ICLPandSIPDA54065.2021.9627465}, pages = {8 Seiten}, year = {2021}, abstract = {For typical cases of non-isolated lightning protection systems (LPS) the impulse currents are investigated which may flow through a human body directly touching a structural part of the LPS. Based on a basic LPS model with conventional down-conductors especially the cases of external and internal steel columns and metal fa{\c{c}}ades are considered and compared. Numerical simulations of the line quantities voltages and currents in the time domain are performed with an equivalent circuit of the entire LPS. As a result it can be stated that by increasing the number of conventional down-conductors and external steel columns the threat for a human being can indeed be reduced, but not down to an acceptable limit. In case of internal steel columns used as natural down-conductors the threat can be reduced sufficiently, depending on the low-resistive connection of the steel columns to the lightning equipotential bonding or the earth termination system, resp. If a metal fa{\c{c}}ade is used the threat for human beings touching is usually very low, if the fa{\c{c}}ade is sufficiently interconnected and multiply connected to the lightning equipotential bonding or the earth termination system, resp.}, language = {en} } @book{Pieper2021, author = {Pieper, Martin}, title = {Quantum mechanics: Introduction to mathematical formulation}, publisher = {Springer}, address = {Wiesbaden}, isbn = {978-3-658-32644-9}, doi = {10.1007/978-3-658-32645-6}, pages = {XIII, 33}, year = {2021}, abstract = {Anyone who has always wanted to understand the hieroglyphs on Sheldon's blackboard in the TV series The Big Bang Theory or who wanted to know exactly what the fate of Schr{\"o}dinger's cat is all about will find a short, descriptive introduction to the world of quantum mechanics in this essential. The text particularly focuses on the mathematical description in the Hilbert space. The content goes beyond popular scientific presentations, but is nevertheless suitable for readers without special prior knowledge thanks to the clear examples.}, language = {en} } @inproceedings{SteuerDankertSharmaBlecketal.2017, author = {Steuer-Dankert, Linda and Sharma, Mamta Rameshwarlal and Bleck, Wolfgang and Leicht-Scholten, Carmen}, title = {Innovation through Diversity - Development of a Diversity and Innovation management concept}, series = {International Conference on Innovation and Management : IAM23017S : Date: July 4-7, 2017, Osaka, Japan}, booktitle = {International Conference on Innovation and Management : IAM23017S : Date: July 4-7, 2017, Osaka, Japan}, editor = {Farn, C. K.}, publisher = {Kuang Hui Chiu}, address = {Osaka}, issn = {2218-6387}, pages = {Panel C}, year = {2017}, abstract = {Acknowledging that a diverse workforce could be a potential source of innovation, the current research deals with the fine details of why diversity management is central to achieving innovation in heterogeneous research groups and how this could be effectively realized in an organization. The types of heterogeneities addressed mainly include gender, qualification, academic discipline and intercultural perspectives. The type of organization being dealt with in this work is a complex association of research institutes at a technical university in Germany (RWTH Aachen University), namely a 'Cluster of Excellence', whereby several institutes of the university work collaboratively in different sub-projects. The 'Cluster of Excellence' is a part of the 'Excellence Initiative' of the German federal and state governments German Research Foundation (DFG) and German Council of Science and Humanities, with the ultimate aim of promoting cutting-edge research. To support interdisciplinary collaboration and thus the performance of the cluster, the development of a diversity and innovation management concept is presently in the conceptual phase and will be described in the frame of this paper. The 3-S-Diversity Model, composed of the three elements: skills, structure and strategy, serves as a basis for the development of the concept. The proposed concept consists of six phases; the first two phases lay the ground work by developing an understanding of the status quo on the forms of diversity in the Cluster of Excellence, the type of organizational structure of the member institutes and the varieties of specialist work cultures of the same. The third and the fourth phases build up on this foundation by means of qualitative and quantitative studies. While the third phase deals with the sensitization of the management level to the close connection between diversity and innovation; the need to manage them thereafter and find tailor-made methods of doing so, the fourth phase shall mainly focus on the mindset of the employees in this regard. The fifth phase shall consolidate the learnings and the ideas developed in the course of the first four phases into an implementable strategy. The ultimate phase shall be the implementation of this concept in the Cluster. The first three phases have been accomplished successfully and the preliminary results are already available.}, language = {en} } @article{BeckerFrauenrathHezeletal.2010, author = {Becker, Meike and Frauenrath, Tobias and Hezel, Fabian and Krombach, Gabriele A. and Kremer, Ute and Koppers, Benedikt and Butenweg, Christoph and Goemmel, Andreas and Utting, Jane F. and Schulz-Menger, Jeanette and Niendorf, Thoralf}, title = {Comparison of left ventricular function assessment using phonocardiogram- and electrocardiogram-triggered 2D SSFP CINE MR imaging at 1.5 T and 3.0 T}, series = {European Radiology}, volume = {20}, journal = {European Radiology}, publisher = {Springer}, address = {Berlin}, issn = {1432-1084 (Onlineausgabe)}, doi = {10.1007/s00330-009-1676-z}, pages = {1344 -- 1355}, year = {2010}, abstract = {Objective: As high-field cardiac MRI (CMR) becomes more widespread the propensity of ECG to interference from electromagnetic fields (EMF) and to magneto-hydrodynamic (MHD) effects increases and with it the motivation for a CMR triggering alternative. This study explores the suitability of acoustic cardiac triggering (ACT) for left ventricular (LV) function assessment in healthy subjects (n=14). Methods: Quantitative analysis of 2D CINE steady-state free precession (SSFP) images was conducted to compare ACT's performance with vector ECG (VCG). Endocardial border sharpness (EBS) was examined paralleled by quantitative LV function assessment. Results: Unlike VCG, ACT provided signal traces free of interference from EMF or MHD effects. In the case of correct Rwave recognition, VCG-triggered 2D CINE SSFP was immune to cardiac motion effects—even at 3.0 T. However, VCG-triggered 2D SSFP CINE imaging was prone to cardiac motion and EBS degradation if R-wave misregistration occurred. ACT-triggered acquisitions yielded LV parameters (end-diastolic volume (EDV), endsystolic volume (ESV), stroke volume (SV), ejection fraction (EF) and left ventricular mass (LVM)) comparable with those derived fromVCG-triggered acquisitions (1.5 T: ESVVCG=(56± 17) ml, EDVVCG=(151±32)ml, LVMVCG=(97±27) g, SVVCG=(94± 19)ml, EFVCG=(63±5)\% cf. ESVACT= (56±18) ml, EDVACT=(147±36) ml, LVMACT=(102±29) g, SVACT=(91± 22) ml, EFACT=(62±6)\%; 3.0 T: ESVVCG=(55±21) ml, EDVVCG=(151±32) ml, LVMVCG=(101±27) g, SVVCG=(96±15) ml, EFVCG=(65±7)\% cf. ESVACT=(54±20) ml, EDVACT=(146±35) ml, LVMACT= (101±30) g, SVACT=(92±17) ml, EFACT=(64±6)\%). Conclusions: ACT's intrinsic insensitivity to interference from electromagnetic fields renders}, language = {en} } @article{RuppRiekeHandschuhetal.2020, author = {Rupp, Matthias and Rieke, Christian and Handschuh, Nils and Kuperjans, Isabel}, title = {Economic and ecological optimization of electric bus charging considering variable electricity prices and CO₂eq intensities}, series = {Transportation Research Part D: Transport and Environment}, volume = {81}, journal = {Transportation Research Part D: Transport and Environment}, number = {Article 102293}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1361-9209}, doi = {10.1016/j.trd.2020.102293}, year = {2020}, abstract = {In many cities, diesel buses are being replaced by electric buses with the aim of reducing local emissions and thus improving air quality. The protection of the environment and the health of the population is the highest priority of our society. For the transport companies that operate these buses, not only ecological issues but also economic issues are of great importance. Due to the high purchase costs of electric buses compared to conventional buses, operators are forced to use electric vehicles in a targeted manner in order to ensure amortization over the service life of the vehicles. A compromise between ecology and economy must be found in order to both protect the environment and ensure economical operation of the buses. In this study, we present a new methodology for optimizing the vehicles' charging time as a function of the parameters CO₂eq emissions and electricity costs. Based on recorded driving profiles in daily bus operation, the energy demands of conventional and electric buses are calculated for the passenger transportation in the city of Aachen in 2017. Different charging scenarios are defined to analyze the influence of the temporal variability of CO₂eq intensity and electricity price on the environmental impact and economy of the bus. For every individual day of a year, charging periods with the lowest and highest costs and emissions are identified and recommendations for daily bus operation are made. To enable both the ecological and economical operation of the bus, the parameters of electricity price and CO₂ are weighted differently, and several charging periods are proposed, taking into account the priorities previously set. A sensitivity analysis is carried out to evaluate the influence of selected parameters and to derive recommendations for improving the ecological and economic balance of the battery-powered electric vehicle. In all scenarios, the optimization of the charging period results in energy cost savings of a maximum of 13.6\% compared to charging at a fixed electricity price. The savings potential of CO₂eq emissions is similar, at 14.9\%. From an economic point of view, charging between 2 a.m. and 4 a.m. results in the lowest energy costs on average. The CO₂eq intensity is also low in this period, but midday charging leads to the largest savings in CO₂eq emissions. From a life cycle perspective, the electric bus is not economically competitive with the conventional bus. However, from an ecological point of view, the electric bus saves on average 37.5\% CO₂eq emissions over its service life compared to the diesel bus. The reduction potential is maximized if the electric vehicle exclusively consumes electricity from solar and wind power.}, language = {en} } @inproceedings{PaulsenHoffstadtKrafftetal.2020, author = {Paulsen, Svea and Hoffstadt, Kevin and Krafft, Simone and Leite, A. and Zang, J. and Fonseca-Zang, W. and Kuperjans, Isabel}, title = {Continuous biogas production from sugarcane as sole substrate}, series = {Energy Reports}, volume = {6}, booktitle = {Energy Reports}, number = {Supplement 1}, publisher = {Elsevier}, doi = {10.1016/j.egyr.2019.08.035}, pages = {153 -- 158}, year = {2020}, language = {en} } @inproceedings{ElMoussaouiKassmiAlexopoulosetal.2021, author = {El Moussaoui, Noureddine and Kassmi, Khalil and Alexopoulos, Spiros and Schwarzer, Klemens and Chayeb, Hamid and Bachiri, Najib}, title = {Simulation studies on a new innovative design of a hybrid solar distiller MSDH alimented with a thermal and photovoltaic energy}, series = {Materialstoday: Proceedings}, booktitle = {Materialstoday: Proceedings}, issn = {2214-7853}, doi = {10.1016/j.matpr.2021.03.115}, year = {2021}, language = {en} } @inproceedings{MistlerButenwegAnthoine2004, author = {Mistler, M. and Butenweg, Christoph and Anthoine, A.}, title = {Evaluation of the failure criterion for masonry by homogenisation}, series = {Proceedings of the Seventh International Conference on Computational Structures Technology : [Lisbon, Portugal, 7 - 9 September 2004] / ed. by B. H. V. Topping and C.A. Mota Soares}, booktitle = {Proceedings of the Seventh International Conference on Computational Structures Technology : [Lisbon, Portugal, 7 - 9 September 2004] / ed. by B. H. V. Topping and C.A. Mota Soares}, publisher = {Civil-Comp Press}, address = {Stirling}, organization = {International Conference on Computational Structures Technology <7, 2004, Lissabon>}, isbn = {0-948749-95-4}, doi = {10.4203/ccp.79.201}, pages = {16 Seiten}, year = {2004}, language = {en} } @article{GoettscheAlexopoulosDuemmleretal.2019, author = {G{\"o}ttsche, Joachim and Alexopoulos, Spiros and D{\"u}mmler, Andreas and Maddineni, S. K.}, title = {Multi-Mirror Array Calculations With Optical Error}, pages = {1 -- 6}, year = {2019}, abstract = {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.}, language = {en} } @inproceedings{SattlerCaminosUerlingsetal.2020, author = {Sattler, Johannes, Christoph and Caminos, Ricardo Alexander Chico and {\"U}rlings, Nicolas and Dutta, Siddharth and Ruiz, Victor and Kalogirou, Soteris and Ktistis, Panayiotis and Agathokleous, Rafaela and Jung, Christian and Alexopoulos, Spiros and Atti, Vikrama Nagababu and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Operational experience and behaviour of a parabolic trough collector system with concrete thermal energy storage for process steam generation in Cyprus}, series = {AIP Conference Proceedings}, booktitle = {AIP Conference Proceedings}, number = {2303}, doi = {10.1063/5.0029278}, pages = {140004-1 -- 140004-10}, year = {2020}, language = {en} } @inproceedings{RendonSchwagerGhiasietal.2020, author = {Rendon, Carlos and Schwager, Christian and Ghiasi, Mona and Schmitz, Pascal and Bohang, Fakhri and Caminos, Ricardo Alexander Chico and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf}, title = {Modeling and upscaling of a pilot bayonettube reactor for indirect solar mixed methane reforming}, series = {AIP Conference Proceedings}, booktitle = {AIP Conference Proceedings}, number = {2303}, doi = {10.1063/5.0029974}, pages = {170012-1 -- 170012-9}, year = {2020}, language = {en} } @inproceedings{HandschuhStollenwerkBorchert2021, author = {Handschuh, Nils and Stollenwerk, Dominik and Borchert, J{\"o}rg}, title = {Operation of thermal storage power plants under high renewable grid penetration}, series = {NEIS 2021: Conference on Sustainable Energy Supply and Energy Storage Systems}, booktitle = {NEIS 2021: Conference on Sustainable Energy Supply and Energy Storage Systems}, publisher = {VDE Verlag}, address = {Berlin}, isbn = {978-3-8007-5651-3}, pages = {261 -- 265}, year = {2021}, abstract = {The planned coal phase-out in Germany by 2038 will lead to the dismantling of power plants with a total capacity of approx. 30 GW. A possible further use of these assets is the conversion of the power plants to thermal storage power plants; the use of these power plants on the day-ahead market is considerably limited by their technical parameters. In this paper, the influence of the technical boundary conditions on the operating times of these storage facilities is presented. For this purpose, the storage power plants were described as an MILP problem and two price curves, one from 2015 with a relatively low renewable penetration (33 \%) and one from 2020 with a high renewable energy penetration (51 \%) are compared. The operating times were examined as a function of the technical parameters and the critical influencing factors were investigated. The thermal storage power plant operation duration and the energy shifted with the price curve of 2020 increases by more than 25 \% compared to 2015.}, language = {en} } @incollection{HoffschmidtAlexopoulosRauetal.2022, author = {Hoffschmidt, Bernhard and Alexopoulos, Spiros and Rau, Christoph and Sattler, Johannes, Christoph and Anthrakidis, Anette and Teixeira Boura, Cristiano Jos{\´e} and O'Connor, B. and Chico Caminos, R.A. and Rend{\´o}n, C. and Hilger, P.}, title = {Concentrating solar power}, series = {Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications}, booktitle = {Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-0-12-819734-9}, pages = {670 -- 724}, year = {2022}, abstract = {The focus of this chapter is the production of power and the use of the heat produced from concentrated solar thermal power (CSP) systems. The chapter starts with the general theoretical principles of concentrating systems including the description of the concentration ratio, the energy and mass balance. The power conversion systems is the main part where solar-only operation and the increase in operational hours. Solar-only operation include the use of steam turbines, gas turbines, organic Rankine cycles and solar dishes. The operational hours can be increased with hybridization and with storage. Another important topic is the cogeneration where solar cooling, desalination and of heat usage is described. Many examples of commercial CSP power plants as well as research facilities from the past as well as current installed and in operation are described in detail. The chapter closes with economic and environmental aspects and with the future potential of the development of CSP around the world.}, language = {en} }