@article{ButenwegMarinkovićFehlingetal.2018,
  author    = {Butenweg, Christoph and Marinković, Marko and Fehling, Ekkehard and Pfetzing, Thomas},
  title     = {Stahlbetonrahmentragwerke mit Ausfachungen aus Mauerwerk unter kombinierten seismischen Belastungen in und senkrecht zur Wandebene},
  series = {Bauingenieur},
  volume    = {93},
  journal   = {Bauingenieur},
  publisher = {VDI Fachmedien},
  address   = {D{\"u}sseldorf},
  isbn      = {0005-6650},
  pages     = {2 -- 10},
  year      = {2018},
  language  = {de}
}
@article{Butenweg2017,
  author    = {Butenweg, Christoph},
  title     = {Die neue Erdbebenfibel. Neue Hilfsmittel f{\"u}r die Leichtbetonindustrie},
  series = {Tagungsband 61. Ulmer Beton Tage 2017},
  journal   = {Tagungsband 61. Ulmer Beton Tage 2017},
  year      = {2017},
  language  = {de}
}
@article{BlankeHagenkampDoeringetal.2021,
  author    = {Blanke, Tobias and Hagenkamp, Markus and D{\"o}ring, Bernd and G{\"o}ttsche, Joachim and Reger, Vitali and Kuhnhenne, Markus},
  title     = {Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates},
  series = {Geothermal Energy},
  volume    = {9},
  journal   = {Geothermal Energy},
  number    = {Article number: 19},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {2195-9706},
  doi       = {10.1186/s40517-021-00201-3},
  pages     = {23 Seiten},
  year      = {2021},
  abstract  = {Previous studies optimized the dimensions of coaxial heat exchangers using constant mass fow rates as a boundary condition. They show a thermal optimal circular ring width of nearly zero. Hydraulically optimal is an inner to outer pipe radius ratio of 0.65 for turbulent and 0.68 for laminar fow types. In contrast, in this study, fow conditions in the circular ring are kept constant (a set of fxed Reynolds numbers) during optimization. This approach ensures fxed fow conditions and prevents inappropriately high or low mass fow rates. The optimization is carried out for three objectives: Maximum energy gain, minimum hydraulic efort and eventually optimum net-exergy balance. The optimization changes the inner pipe radius and mass fow rate but not the Reynolds number of the circular ring. The thermal calculations base on Hellstr{\"o}m's borehole resistance and the hydraulic optimization on individually calculated linear loss of head coefcients. Increasing the inner pipe radius results in decreased hydraulic losses in the inner pipe but increased losses in the circular ring. The net-exergy diference is a key performance indicator and combines thermal and hydraulic calculations. It is the difference between thermal exergy fux and hydraulic efort. The Reynolds number in the circular ring is instead of the mass fow rate constant during all optimizations. The result from a thermal perspective is an optimal width of the circular ring of nearly zero. The hydraulically optimal inner pipe radius is 54\% of the outer pipe radius for laminar fow and 60\% for turbulent fow scenarios. Net-exergetic optimization shows a predominant infuence of hydraulic losses, especially for small temperature gains. The exact result depends on the earth's thermal properties and the fow type. Conclusively, coaxial geothermal probes' design should focus on the hydraulic optimum and take the thermal optimum as a secondary criterion due to the dominating hydraulics.},
  language  = {en}
}
@article{SchuellerRuhlDinstuehlerSengeretal.2022,
  author    = {Sch{\"u}ller-Ruhl, Aaron and Dinst{\"u}hler, Leonard and Senger, Thorsten and Bergfeld, Stefan and Ingenhag, Christian and Fleischhaker, Robert},
  title     = {Direct fabrication of arbitrary phase masks in optical glass via ultra-short pulsed laser writing of refractive index modifications},
  series = {Applied Physics B},
  volume    = {128},
  journal   = {Applied Physics B},
  number    = {Article number: 208},
  editor    = {Mackenzie, Jacob},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1432-0649 (Online)},
  doi       = {10.1007/s00340-022-07928-2},
  pages     = {1 -- 11},
  year      = {2022},
  abstract  = {We study the possibility to fabricate an arbitrary phase mask in a one-step laser-writing process inside the volume of an optical glass substrate. We derive the phase mask from a Gerchberg-Saxton-type algorithm as an array and create each individual phase shift using a refractive index modification of variable axial length. We realize the variable axial length by superimposing refractive index modifications induced by an ultra-short pulsed laser at different focusing depth. Each single modification is created by applying 1000 pulses with 15 μJ pulse energy at 100 kHz to a fixed spot of 25 μm diameter and the focus is then shifted axially in steps of 10 μm. With several proof-of-principle examples, we show the feasibility of our method. In particular, we identify the induced refractive index change to about a value of Δn=1.5⋅10-3. We also determine our current limitations by calculating the overlap in the form of a scalar product and we discuss possible future improvements.},
  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}
}
@article{GeorgStollenwerkReinkensmeieretal.2021,
  author    = {Georg, J{\"o}rg Heiner and Stollenwerk, Dominik and Reinkensmeier, Sebastian and Jungbluth, Christian},
  title     = {„Smartes" Laden an {\"o}ffentlich zug{\"a}nglichen Lades{\"a}ulen - Teil 1: Quo vadis, Marktdesign?},
  series = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  volume    = {71},
  journal   = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  number    = {1/2},
  publisher = {ETV Energieverlag},
  address   = {Essen},
  isbn      = {0720-6240},
  issn      = {0013-743X},
  pages     = {64 -- 69},
  year      = {2021},
  language  = {de}
}
@article{StollenwerkReinkensmeierGeorgetal.2021,
  author    = {Stollenwerk, Dominik and Reinkensmeier, Sebastian and Georg, J{\"o}rg Heiner and Jungbluth, Christian},
  title     = {„Smartes" Laden an {\"o}ffentlich zug{\"a}nglichen Lades{\"a}ulen - Teil 2: USER-Verhalten und -Erwartungen},
  series = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  volume    = {71},
  journal   = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  number    = {3},
  publisher = {ETV Energieverlag},
  address   = {Essen},
  isbn      = {0720-6240},
  issn      = {0013-743X},
  pages     = {38 -- 42},
  year      = {2021},
  language  = {de}
}
@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}
}
@article{MarinkovićFloresCalvinistiButenweg2020,
  author    = {Marinković, Marko and Flores Calvinisti, Santiago and Butenweg, Christoph},
  title     = {Numerical analysis of reinforced concrete frame buildings with decoupled infill walls},
  series = {Building Materials and Structures},
  volume    = {63},
  journal   = {Building Materials and Structures},
  number    = {4},
  publisher = {Society for Materials and Structures Testing of Serbia},
  address   = {Belgrad},
  issn      = {2217-8139},
  doi       = {10.5937/GRMK2004013M},
  pages     = {13 -- 48},
  year      = {2020},
  abstract  = {Reinforced concrete (RC) buildings with masonry infill walls are widely used in many countries all over the world. Although infills are considered as non-structural elements, they significantly change dynamic characteristics of RC frame structures during earthquake excitation. Recently, significant effort was spent on studying decoupled infills, which are isolated from the surrounding frame usually by adding a gap between frame and infill. In this case, the frame deformation does not activate infill wall, thus infills are not influencing the behaviour of the frame. This paper presents the results of the investigation of the behaviour of RC frame buildings with the INODIS system that decouples masonry infills from the surrounding frame. Effect of masonry infill decoupling was investigated first on the one-bay onestorey frame. This was used as a base for parametric study on the frames with more bays and storeys, as well as on the building level. Change of stiffness and dynamic characteristics was analysed as well as response under earthquake loading. Comparison with the bare frame and traditionally infilled frame was performed. The results show that behaviour of the decoupled infilled frames is similar to the bare frame, whereas behaviour of frames with traditional infills is significantly different and demands complex numerical models. This means that if adequate decoupling is applied, design of},
  language  = {mul}
}