@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{ButenwegMarinkovicPhlippetal.2022, author = {Butenweg, Christoph and Marinkovic, Marko and Phlipp, Michel and Lins, Robin and Renaut, Philipp}, title = {Isolierung und BIM-basiertes Bauwerksmonitoring des neuen Geb{\"a}udekomplexes f{\"u}r das BioSense-Institut in Novi Sad, Serbien}, series = {Bauingenieur}, volume = {97}, journal = {Bauingenieur}, number = {6}, editor = {Haghsheno, Shervin}, publisher = {VDI Fachmedien}, address = {D{\"u}sseldorf}, issn = {1436-4867}, doi = {10.37544/0005-6650-2022-06-28}, pages = {S3 -- S5}, year = {2022}, abstract = {Im Norden von Serbien erfolgt in Novi Sad der Neubau eines modernen Forschungsgeb{\"a}udes f{\"u}r das BioSense-Institut mit finanzieller Unterst{\"u}tzung durch die Eu-rop{\"a}ische Union. Der Geb{\"a}udeteil mit Laboren wird zum Schutz und zur Sicherstellung des reibungslosen Betriebs der sensiblen und kapitalintensiven technischen Einbauten mit ei-ner Erdbebenisolierung mit integrierter K{\"o}rperschallisolation versehen. Zus{\"a}tzlich wird der entkoppelte Laborteil des For-schungsgeb{\"a}udes mit einem BIM-basierten Bauwerksmonito-ring versehen, um {\"A}nderungen des Geb{\"a}udezustands jederzeit abfragen und beurteilen zu k{\"o}nnen.}, language = {de} } @article{HoffstadtPohenDickeetal.2020, author = {Hoffstadt, Kevin and Pohen, Gino D. and Dicke, Max D. and Paulsen, Svea and Krafft, Simone and Zang, Joachim W. and Fonseca-Zang, Warde A. da and Leite, Athaydes and Kuperjans, Isabel}, title = {Challenges and prospects of biogas from energy cane as supplement to bioethanol production}, series = {Agronomy}, volume = {10}, journal = {Agronomy}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2073-4395}, doi = {10.3390/agronomy10060821}, year = {2020}, abstract = {Innovative breeds of sugar cane yield up to 2.5 times as much organic matter as conventional breeds, resulting in a great potential for biogas production. The use of biogas production as a complementary solution to conventional and second-generation ethanol production in Brazil may increase the energy produced per hectare in the sugarcane sector. Herein, it was demonstrated that through ensiling, energy cane can be conserved for six months; the stored cane can then be fed into a continuous biogas process. This approach is necessary to achieve year-round biogas production at an industrial scale. Batch tests revealed specific biogas potentials between 400 and 600 LN/kgVS for both the ensiled and non-ensiled energy cane, and the specific biogas potential of a continuous biogas process fed with ensiled energy cane was in the same range. Peak biogas losses through ensiling of up to 27\% after six months were observed. Finally, compared with second-generation ethanol production using energy cane, the results indicated that biogas production from energy cane may lead to higher energy yields per hectare, with an average energy yield of up to 162 MWh/ha. Finally, the Farm²CBG concept is introduced, showing an approach for decentralized biogas production.}, language = {en} } @article{RossiWinandsButenweg2022, author = {Rossi, Leonardo and Winands, Mark H. M. and Butenweg, Christoph}, title = {Monte Carlo Tree Search as an intelligent search tool in structural design problems}, series = {Engineering with Computers : An International Journal for Simulation-Based Engineering}, volume = {38}, journal = {Engineering with Computers : An International Journal for Simulation-Based Engineering}, number = {4}, editor = {Zhang, Jessica}, publisher = {Springer Nature}, address = {Cham}, issn = {1435-5663}, doi = {10.1007/s00366-021-01338-2}, pages = {3219 -- 3236}, year = {2022}, abstract = {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.}, language = {en} } @article{HoffstadtCheenakulaNikolauszetal.2023, author = {Hoffstadt, Kevin and Cheenakula, Dheeraja and Nikolausz, Marcell and Krafft, Simone and Harms, Hauke and Kuperjans, Isabel}, title = {Design and construction of a new reactor for flexible biomethanation of hydrogen}, series = {Fermentation}, volume = {9}, journal = {Fermentation}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2311-5637}, doi = {10.3390/fermentation9080774}, pages = {1 -- 16}, year = {2023}, abstract = {The increasing share of renewable electricity in the grid drives the need for sufficient storage capacity. Especially for seasonal storage, power-to-gas can be a promising approach. Biologically produced methane from hydrogen produced from surplus electricity can be used to substitute natural gas in the existing infrastructure. Current reactor types are not or are poorly optimized for flexible methanation. Therefore, this work proposes a new reactor type with a plug flow reactor (PFR) design. Simulations in COMSOL Multiphysics ® showed promising properties for operation in laminar flow. An experiment was conducted to support the simulation results and to determine the gas fraction of the novel reactor, which was measured to be 29\%. Based on these simulations and experimental results, the reactor was constructed as a 14 m long, 50 mm diameter tube with a meandering orientation. Data processing was established, and a step experiment was performed. In addition, a kLa of 1 h-1 was determined. The results revealed that the experimental outcomes of the type of flow and gas fractions are in line with the theoretical simulation. The new design shows promising properties for flexible methanation and will be tested.}, language = {en} } @article{RegerKuhnhenneHachuletal.2019, author = {Reger, Vitali and Kuhnhenne, Markus and Hachul, Helmut and D{\"o}ring, Bernd and Blanke, Tobias and G{\"o}ttsche, Joachim}, title = {Plusenergiegeb{\"a}ude 2.0 in Stahlleichtbauweise}, series = {Stahlbau}, volume = {88}, journal = {Stahlbau}, number = {6}, publisher = {Ernst \& Sohn}, address = {Berlin}, issn = {1437-1049 (E-journal), 0038-9145 (print)}, doi = {10.1002/stab.201900034}, pages = {522 -- 528}, year = {2019}, language = {de} } @article{KirschkampJoeckelWaehlischetal.1998, author = {Kirschkamp, T. and J{\"o}ckel, M. and W{\"a}hlisch, Georg and Barry, J. C.}, title = {Konstruktion eines Modellauges zur Simulation von Purkinje-Spiegelbildern f{\"u}r die Bestimmung der Kr{\"u}mmungsradien und der Lage der Augenlinse}, series = {Biomedizinische Technik = Biomedical Engineering}, volume = {Bd. 43}, journal = {Biomedizinische Technik = Biomedical Engineering}, number = {H. 11}, issn = {1862-278X (E-Journal); 0013-5585 (Print)}, pages = {318 -- 325}, year = {1998}, language = {de} } @article{CheenakulaHoffstadtKrafftetal.2022, author = {Cheenakula, Dheeraja and Hoffstadt, Kevin and Krafft, Simone and Reinecke, Diana and Klose, Holger and Kuperjans, Isabel and Gr{\"o}mping, Markus}, title = {Anaerobic digestion of algal-bacterial biomass of an Algal Turf Scrubber system}, series = {Biomass Conversion and Biorefinery}, volume = {13}, journal = {Biomass Conversion and Biorefinery}, publisher = {Springer}, address = {Berlin}, issn = {2190-6823}, doi = {10.1007/s13399-022-03236-z}, pages = {15 Seiten}, year = {2022}, abstract = {This study investigated the anaerobic digestion of an algal-bacterial biofilm grown in artificial wastewater in an Algal Turf Scrubber (ATS). The ATS system was located in a greenhouse (50°54′19ʺN, 6°24′55ʺE, Germany) and was exposed to seasonal conditions during the experiment period. The methane (CH4) potential of untreated algal-bacterial biofilm (UAB) and thermally pretreated biofilm (PAB) using different microbial inocula was determined by anaerobic batch fermentation. Methane productivity of UAB differed significantly between microbial inocula of digested wastepaper, a mixture of manure and maize silage, anaerobic sewage sludge, and percolated green waste. UAB using sewage sludge as inoculum showed the highest methane productivity. The share of methane in biogas was dependent on inoculum. Using PAB, a strong positive impact on methane productivity was identified for the digested wastepaper (116.4\%) and a mixture of manure and maize silage (107.4\%) inocula. By contrast, the methane yield was significantly reduced for the digested anaerobic sewage sludge (50.6\%) and percolated green waste (43.5\%) inocula. To further evaluate the potential of algal-bacterial biofilm for biogas production in wastewater treatment and biogas plants in a circular bioeconomy, scale-up calculations were conducted. It was found that a 0.116 km2 ATS would be required in an average municipal wastewater treatment plant which can be viewed as problematic in terms of space consumption. However, a substantial amount of energy surplus (4.7-12.5 MWh a-1) can be gained through the addition of algal-bacterial biomass to the anaerobic digester of a municipal wastewater treatment plant. Wastewater treatment and subsequent energy production through algae show dominancy over conventional technologies.}, language = {en} } @article{MorandiButenwegBreisetal.2022, author = {Morandi, Paolo and Butenweg, Christoph and Breis, Khaled and Beyer, Katrin and Magenes, Guido}, title = {Latest findings on the behaviour factor q for the seismic design of URM buildings}, series = {Bulletin of Earthquake Engineering}, volume = {20}, journal = {Bulletin of Earthquake Engineering}, number = {11}, editor = {Ansal, Atilla}, publisher = {Springer Nature}, address = {Cham}, issn = {1573-1456}, doi = {10.1007/s10518-022-01419-7}, pages = {5797 -- 5848}, year = {2022}, abstract = {Recent earthquakes as the 2012 Emilia earthquake sequence showed that recently built unreinforced masonry (URM) buildings behaved much better than expected and sustained, despite the maximum PGA values ranged between 0.20-0.30 g, either minor damage or structural damage that is deemed repairable. Especially low-rise residential and commercial masonry buildings with a code-conforming seismic design and detailing behaved in general very well without substantial damages. The low damage grades of modern masonry buildings that was observed during this earthquake series highlighted again that codified design procedures based on linear analysis can be rather conservative. Although advances in simulation tools make nonlinear calculation methods more readily accessible to designers, linear analyses will still be the standard design method for years to come. The present paper aims to improve the linear seismic design method by providing a proper definition of the q-factor of URM buildings. These q-factors are derived for low-rise URM buildings with rigid diaphragms which represent recent construction practise in low to moderate seismic areas of Italy and Germany. The behaviour factor components for deformation and energy dissipation capacity and for overstrength due to the redistribution of forces are derived by means of pushover analyses. Furthermore, considerations on the behaviour factor component due to other sources of overstrength in masonry buildings are presented. As a result of the investigations, rationally based values of the behaviour factor q to be used in linear analyses in the range of 2.0-3.0 are proposed.}, 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{BergPostweilerSteuerDankertLeichtScholten2023, author = {Berg-Postweiler, Julia and Steuer-Dankert, Linda and Leicht-Scholten, Carmen}, title = {One size does not fit all: Applying antibias trainings in academia}, series = {The International Journal of Organizational Diversity}, volume = {24}, journal = {The International Journal of Organizational Diversity}, number = {1}, publisher = {Common Ground Research Networks}, issn = {2328-6261 (Print)}, doi = {10.18848/2328-6261/CGP/v24i01/1-23}, pages = {1 -- 23}, year = {2023}, abstract = {Antibias training is increasingly demanded and practiced in academia and industry to increase employees' sensitivity to discrimination, racism, and diversity. Under the heading of "Diversity Management," antibias trainings are mainly offered as one-off workshops intending to raise awareness of unconscious biases, create a diversity-affirming corporate culture, promote awareness of the potential of diversity, and ultimately enable the reflection of diversity in development processes. However, coming from childhood education, research and scientific articles on the sustainable effectiveness of antibias in adulthood, especially in academia, are very scarce. In order to fill this research gap, the article aims to explore how sustainable the effects of individual antibias trainings on participants' behavior are. In order to investigate this, participant observation in a qualitative pre-post setting was conducted, analyzing antibias training in an academic context. Two observers actively participated in the training sessions and documented the activities and reflection processes of the participants. Overall, the results question the effectiveness of single antibias trainings and show that a target-group adaptive approach is mandatory owing to the background of the approach in early childhood education. Therefore, antibias work needs to be adapted to the target group's needs and realities of life. Furthermore, the study reveals that single antibias trainings must be embedded in a holistic diversity management approach to stimulate sustainable reflection processes among the target group. This article is one of the first to scientifically evaluate antibias training effectiveness, especially in engineering sciences and the university context.}, language = {en} } @article{ButenwegMarinkovićKubalskietal.2018, author = {Butenweg, Christoph and Marinković, Marko and Kubalski, Thomas and Fehling, Ekkehard and Pfetzing, Thomas and Meyer, Udo}, title = {Auslegung von Stahlbetonrahmentragwerken mit Ausfachungen aus Ziegelmauerwerk (Teil 2)}, series = {Ziegelindustrie international : ZI = Brick and tile industry international}, journal = {Ziegelindustrie international : ZI = Brick and tile industry international}, number = {6}, editor = {Voss, Michael}, publisher = {Bauverlag BV GmbH}, address = {G{\"u}tersloh}, issn = {0341-0552}, pages = {24 -- 43}, year = {2018}, abstract = {Im Rahmen des europ{\"a}ischen Verbundprojekts INSYSME wurden von den deutschen Partnern die Systeme IMES und INODIS zur Verbesserung des seismischen Verhaltens von ausgefachten Stahlbetonrahmen entwickelt. Ziel beider Systeme ist es, Stahlbetonrahmen und Ausfachung zu entkoppeln, anstatt die Tragf{\"a}higkeit durch aufwendige und kostspielige zus{\"a}tzliche Bewehrungseinlagen zu erh{\"o}hen. Erste Ergebnisse des Systems IMES f{\"u}r Belastungen in und senkrecht zu der Wandebene werden vorgestellt.}, language = {de} } @article{ButenwegBursiPaolaccietal.2021, author = {Butenweg, Christoph and Bursi, Oreste S. and Paolacci, Fabrizio and Marinković, Marko and Lanese, Igor and Nardin, Chiara and Quinci, Gianluca}, title = {Seismic performance of an industrial multi-storey frame structure with process equipment subjected to shake table testing}, series = {Engineering Structures}, volume = {243}, journal = {Engineering Structures}, number = {15}, editor = {Yang, J.}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0141-0296}, doi = {10.1016/j.engstruct.2021.112681}, year = {2021}, abstract = {Past earthquakes demonstrated the high vulnerability of industrial facilities equipped with complex process technologies leading to serious damage of process equipment and multiple and simultaneous release of hazardous substances. Nonetheless, current standards for seismic design of industrial facilities are considered inadequate to guarantee proper safety conditions against exceptional events entailing loss of containment and related consequences. On these premises, the SPIF project -Seismic Performance of Multi-Component Systems in Special Risk Industrial Facilities- was proposed within the framework of the European H2020 SERA funding scheme. In detail, the objective of the SPIF project is the investigation of the seismic behaviour of a representative industrial multi-storey frame structure equipped with complex process components by means of shaking table tests. Along this main vein and in a performance-based design perspective, the issues investigated in depth are the interaction between a primary moment resisting frame (MRF) steel structure and secondary process components that influence the performance of the whole system; and a proper check of floor spectra predictions. The evaluation of experimental data clearly shows a favourable performance of the MRF structure, some weaknesses of local details due to the interaction between floor crossbeams and process components and, finally, the overconservatism of current design standards w.r.t. floor spectra predictions.}, language = {en} } @article{SchwagerFleschSchwarzboezletal.2022, author = {Schwager, Christian and Flesch, Robert and Schwarzb{\"o}zl, Peter and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e}}, title = {Advanced two phase flow model for transient molten salt receiver system simulation}, series = {Solar Energy}, volume = {232}, journal = {Solar Energy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0038-092X (print)}, doi = {10.1016/j.solener.2021.12.065}, pages = {362 -- 375}, year = {2022}, abstract = {In order to realistically predict and optimize the actual performance of a concentrating solar power (CSP) plant sophisticated simulation models and methods are required. This paper presents a detailed dynamic simulation model for a Molten Salt Solar Tower (MST) system, which is capable of simulating transient operation including detailed startup and shutdown procedures including drainage and refill. For appropriate representation of the transient behavior of the receiver as well as replication of local bulk and surface temperatures a discretized receiver model based on a novel homogeneous two-phase (2P) flow modelling approach is implemented in Modelica Dymola®. This allows for reasonable representation of the very different hydraulic and thermal properties of molten salt versus air as well as the transition between both. This dynamic 2P receiver model is embedded in a comprehensive one-dimensional model of a commercial scale MST system and coupled with a transient receiver flux density distribution from raytracing based heliostat field simulation. This enables for detailed process prediction with reasonable computational effort, while providing data such as local salt film and wall temperatures, realistic control behavior as well as net performance of the overall system. Besides a model description, this paper presents some results of a validation as well as the simulation of a complete startup procedure. Finally, a study on numerical simulation performance and grid dependencies is presented and discussed.}, language = {en} } @article{JablonowskiKollmannNabeletal.2016, author = {Jablonowski, Nicolai David and Kollmann, Tobias and Nabel, Moritz and Damm, Tatjana and Klose, Holger and M{\"u}ller, Michael and Bl{\"a}sing, Marc and Seebold, S{\"o}ren and Krafft, Simone and Kuperjans, Isabel and Dahmen, Markus and Schurr, Ulrich}, title = {Valorization of Sida (Sida hermaphrodita) biomass for multiple energy purposes}, series = {GCB [Global Change Biology] Bioenergy}, volume = {9}, journal = {GCB [Global Change Biology] Bioenergy}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1757-1707 (online)}, doi = {10.1111/gcbb.12346}, pages = {202 -- 214}, year = {2016}, abstract = {The performance and biomass yield of the perennial energy plant Sida hermaphrodita (hereafter referred to as Sida) as a feedstock for biogas and solid fuel was evaluated throughout one entire growing period at agricultural field conditions. A Sida plant development code was established to allow comparison of the plant growth stages and biomass composition. Four scenarios were evaluated to determine the use of Sida biomass with regard to plant development and harvest time: (i) one harvest for solid fuel only; (ii) one harvest for biogas production only; (iii) one harvest for biogas production, followed by a harvest of the regrown biomass for solid fuel; and (iv) two consecutive harvests for biogas production. To determine Sida's value as a feedstock for combustion, we assessed the caloric value, the ash quality, and melting point with regard to DIN EN ISO norms. The results showed highest total dry biomass yields of max. 25 t ha⁻¹, whereas the highest dry matter of 70\% to 80\% was obtained at the end of the growing period. Scenario (i) clearly indicated the highest energy recovery, accounting for 439 288 MJ ha⁻¹; the energy recovery of the four scenarios from highest to lowest followed this order: (i) ≫ (iii) ≫ (iv) > (ii). Analysis of the Sida ashes showed a high melting point of >1500 °C, associated with a net calorific value of 16.5-17.2 MJ kg⁻¹. All prerequisites for DIN EN ISO norms were achieved, indicating Sida's advantage as a solid energy carrier without any post-treatment after harvesting. Cell wall analysis of the stems showed a constant lignin content after sampling week 16 (July), whereas cellulose had already reached a plateau in sampling week 4 (April). The results highlight Sida as a promising woody, perennial plant, providing biomass for flexible and multipurpose energy applications.}, language = {en} } @article{Kern2016, author = {Kern, Alexander}, title = {Blitz- und {\"U}berspannungsschutz von Kernkraftwerken - Nachweisf{\"u}hrung der ausreichenden Sicherheit f{\"u}r leittechnische Einrichtungen auch bei Blitzeinschl{\"a}gen mit extremen Parametern}, series = {Atw. International Journal for Nuclear Power}, volume = {61}, journal = {Atw. International Journal for Nuclear Power}, number = {8/9}, publisher = {Inforum}, address = {Berlin}, issn = {1431-5254}, pages = {534 -- 543}, year = {2016}, abstract = {F{\"u}r das Auftreten extremer Wetterereignisse werden f{\"u}r Kernkraftwerke Eintrittsh{\"a}ufigkeiten f{\"u}r nicht mehr beherrschbare Zust{\"a}nde von unter 10⁻⁴/a gefordert. Dies gilt auch f{\"u}r die Einwirkung von Blitzeinschl{\"a}gen. Die bisherige Nachweisf{\"u}hrung zu Blitz- und {\"U}berspannungsschutz eines KKW in Deutschland ist deterministisch. In diesem Bericht werden das Vorgehen f{\"u}r einen entsprechenden Nachweis f{\"u}r leittechnische Einrichtungen der Sicherheitstechnik von KKW, der zur geforderten Zielgr{\"o}ße der Eintrittsh{\"a}ufigkeit f{\"u}hrt. Die Ergebnisse werden zusammenfassend bewertet.}, language = {de} } @article{MahmoudiFleischhakerSahraietal.2008, author = {Mahmoudi, Mohammad and Fleischhaker, Robert and Sahrai, Mostafa and Evers, J{\"o}rg}, title = {Group velocity control in the ultraviolet domain via interacting dark-state resonances}, series = {Journal of physics B: Atomic, molecular and optical physics}, volume = {41}, journal = {Journal of physics B: Atomic, molecular and optical physics}, number = {2}, issn = {0953-4075}, doi = {10.1088/0953-4075/41/2/025504}, pages = {25504 -- 25600}, year = {2008}, language = {en} } @article{FleischhakerKraussSchaettigeretal.2013, author = {Fleischhaker, Robert and Krauß, Nico and Sch{\"a}ttiger, Farina and Dekorsy, Thomas}, title = {Consistent characterization of semiconductor saturable absorber mirrors with singe-pulse and pump-probe spectroscopy}, series = {Optics Express}, volume = {21}, journal = {Optics Express}, number = {6}, publisher = {Optica}, address = {Washington, DC}, issn = {1094-4087}, doi = {10.1364/OE.21.006764}, pages = {6764 -- 6776}, year = {2013}, language = {en} } @article{FleischhakerEvers2011, author = {Fleischhaker, Robert and Evers, J{\"o}rg}, title = {A Maxwell-Schr{\"o}dinger solver for quantum optical few-level systems}, series = {Computer Physics Communications}, volume = {182}, journal = {Computer Physics Communications}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0010-4655}, doi = {10.1016/j.cpc.2010.10.018}, pages = {739 -- 747}, year = {2011}, abstract = {The msprop program presented in this work is capable of solving the Maxwell-Schr{\"o}dinger equations for one or several laser fields propagating through a medium of quantum optical few-level systems in one spatial dimension and in time. In particular, it allows to numerically treat systems in which a laser field interacts with the medium with both its electric and magnetic component at the same time. The internal dynamics of the few-level system is modeled by a quantum optical master equation which includes coherent processes due to optical transitions driven by the laser fields as well as incoherent processes due to decay and dephasing. The propagation dynamics of the laser fields is treated in slowly varying envelope approximation resulting in a first order wave equation for each laser field envelope function. The program employs an Adams predictor formula second order in time to integrate the quantum optical master equation and a Lax-Wendroff scheme second order in space and time to evolve the wave equations for the fields. The source function in the Lax-Wendroff scheme is specifically adapted to allow taking into account the simultaneous coupling of a laser field to the polarization and the magnetization of the medium. To reduce execution time, a customized data structure is implemented and explained. In three examples the features of the program are demonstrated and the treatment of a system with a phase-dependent cross coupling of the electric and magnetic field component of a laser field is shown.}, language = {en} } @article{FleischhakerEversDey2010, author = {Fleischhaker, Robert and Evers, J{\"o}rg and Dey, Tarak N.}, title = {Phase modulation induced by cooperative effects in electromagnetically induced transparency}, series = {Physical Review A - Atomic, molecular, and optical physics}, volume = {82}, journal = {Physical Review A - Atomic, molecular, and optical physics}, number = {1}, publisher = {AIP Publishing}, address = {Melville, NY}, issn = {1050-2947}, doi = {10.1103/PhysRevA.82.013815}, pages = {013815}, year = {2010}, abstract = {We analyze the influence of dipole-dipole interactions in an electromagnetically induced transparency set up for a density at the onset of cooperative effects. To this end, we include mean-field models for the influence of local-field corrections and radiation trapping into our calculation. We show both analytically and numerically that the polarization contribution to the local field strongly modulates the phase of a weak pulse. We give an intuitive explanation for this local-field-induced phase modulation and demonstrate that it distinctively differs from the nonlinear self-phase-modulation that a strong pulse experiences in a Kerr medium.}, language = {en} } @article{FleischhakerEvers2008, author = {Fleischhaker, Robert and Evers, J{\"o}rg}, title = {Nonlinear effects in pulse propagation through Doppler-broadened closed-loop atomic media}, series = {Physical Review A - Atomic, molecular, and optical physics}, volume = {77}, journal = {Physical Review A - Atomic, molecular, and optical physics}, number = {4}, issn = {1050-2947}, doi = {10.1103/PhysRevA.77.043805}, pages = {043805}, year = {2008}, language = {en} } @article{FleischhakerEvers2008, author = {Fleischhaker, Robert and Evers, J{\"o}rg}, title = {Four-wave mixing enhanced white-light cavity}, series = {Physical Review A - Atomic, molecular, and optical physics}, volume = {78}, journal = {Physical Review A - Atomic, molecular, and optical physics}, number = {5}, issn = {0556-2791}, pages = {051802(R)}, year = {2008}, language = {en} } @article{HenriquesJuradoGrieseretal.2020, author = {Henriques, A. and Jurado, B. and Grieser, M. and Denis-Petit, D. and Chiron, T. and Gaudefroy, L. and Glorius, J. and Langer, Christoph and Litvinov, Yu. A. and Mathieu, L. and Meot, V. and Perez-Sanchez, R. and Pibernat, J. and Reifarth, R. and Roig, O. and Thomas, B. and Thomas, B. A. and Thomas, J. C. and Tsekhanovich, I.}, title = {Indirect measurements of neutron cross-secti at heavy-ion storage rings}, series = {Journal of Physics: Conference Series}, volume = {1668}, journal = {Journal of Physics: Conference Series}, number = {Art. 012019}, publisher = {IOP}, address = {Bristol}, doi = {10.1088/1742-6596/1668/1/012019}, year = {2020}, abstract = {Cross sections for neutron-induced reactions of short-lived nuclei are essential for nuclear astrophysics since these reactions in the stars are responsible for the production of most heavy elements in the universe. These reactions are also key in applied domains like energy production and medicine. Nevertheless, neutron-induced cross-section measurements can be extremely challenging or even impossible to perform due to the radioactivity of the targets involved. Indirect measurements through the surrogate-reaction method can help to overcome these difficulties. The surrogate-reaction method relies on the use of an alternative reaction that will lead to the formation of the same excited nucleus as in the neutron-induced reaction of interest. The decay probabilities (for fission, neutron and gamma-ray emission) of the nucleus produced via the surrogate reaction allow one to constrain models and the prediction of the desired neutron cross sections. We propose to perform surrogate reaction measurements in inverse kinematics at heavy-ion storage rings, in particular at the CRYRING@ESR of the GSI/FAIR facility. We present the conceptual idea of the most promising setup to measure for the first time simultaneously the fission, neutron and gamma-ray emission probabilities. The results of the first simulations considering the 238U(d,d') reaction are shown, as well as new technical developments that are being carried out towards this set-up.}, language = {en} } @article{VargaDavinsonGloriusetal.2020, author = {Varga, Laszlo and Davinson, Thomas and Glorius, Jan and Jurado, Beatrix and Langer, Christoph and Lederer-Woods, Claudia and Litvinov, Yuri A. and Reifarth, Rene and Slavkovska, Zuzana and St{\"o}hlker, Thomas and Woods, Phil J. and Xing, Yuan Ming}, title = {Towards background-free studies of capture reaction in a heavy-ion storage ring}, series = {Journal of Physics: Conference Series}, volume = {1668}, journal = {Journal of Physics: Conference Series}, number = {Art 012046}, publisher = {IOP}, address = {Bristol}, year = {2020}, abstract = {Stored and cooled, highly-charged ions offer unprecedented capabilities for precision studies in the realm of atomic, nuclear structure and astrophysics[1]. After the successful investigation of the 96Ru(p,7)97Rh reaction cross section in 2009[2], the first measurement of the 124Xe(p,7)125Cs reaction cross section has been performed with decelerated, fully-ionized 124Xe ions in 2016 at the Experimental Storage Ring (ESR) of GSI[3]. Using a Double Sided Silicon Strip Detector, introduced directly into the ultra-high vacuum environment of a storage ring, the 125Cs proton-capture products have been successfully detected. The cross section has been measured at 5 different energies between 5.5AMeV and 8AMeV, on the high energy tail of the Gamow-window for hot, explosive scenarios such as supernovae and X-ray binaries. The elastic scattering on the H2 gas jet target is the major source of background to count the (p,7) events. Monte Carlo simulations show that an additional slit system in the ESR in combination with the energy information of the Si detector will enable background free measurements of the proton-capture products. The corresponding hardware is being prepared and will increase the sensitivity of the method tremendously.}, language = {en} } @article{RiekeStollenwerkDahmenetal.2018, author = {Rieke, Christian and Stollenwerk, Dominik and Dahmen, Markus and Pieper, Martin}, title = {Modeling and optimization of a biogas plant for a demand-driven energy supply}, series = {Energy}, volume = {145}, journal = {Energy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0360-5442}, doi = {10.1016/j.energy.2017.12.073}, pages = {657 -- 664}, year = {2018}, abstract = {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.}, language = {en} } @article{DotzauerPfeifferLaueretal.2019, author = {Dotzauer, Martin and Pfeiffer, Diana and Lauer, Markus and Pohl, Marcel and Mauky, Eric and B{\"a}r, Katharina and Sonnleitner, Matthias and Z{\"o}rner, Wilfried and Hudde, Jessica and Schwarz, Bj{\"o}rn and Faßauer, Burkhardt and Dahmen, Markus and Rieke, Christian and Herbert, Johannes and Thr{\"a}n, Daniela}, title = {How to measure flexibility - Performance indicators for demand driven power generation from biogas plants}, series = {Renewable Energy}, journal = {Renewable Energy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0960-1481}, doi = {10.1016/j.renene.2018.10.021}, pages = {135 -- 146}, year = {2019}, 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{SrivastavaChaharSharmaetal.2017, author = {Srivastava, A. and Chahar, V. and Sharma, V. and Sun, Y. and Bol, R. and Knolle, F. and Schnug, E. and Hoyler, Friedrich and Naskar, N. and Lahiri, S. and Patnaik, R.}, title = {Study of uranium toxicity using low-background gamma-ray spectrometry}, series = {Journal of Radioanalytical and Nuclear Chemistry}, journal = {Journal of Radioanalytical and Nuclear Chemistry}, number = {Online first}, publisher = {Springer}, address = {Berlin}, issn = {1588-2780}, doi = {10.1007/s10967-017-5466-9}, pages = {1 -- 7}, year = {2017}, language = {en} } @article{BirklDiendorferKernetal.2018, author = {Birkl, Josef and Diendorfer, Gerhard and Kern, Alexander and Thern, Stephan}, title = {Extrem hohe Blitzstr{\"o}me}, series = {Elektropraktiker}, volume = {72}, journal = {Elektropraktiker}, number = {3}, publisher = {Huss Medien}, address = {Berlin}, pages = {217 -- 225}, year = {2018}, abstract = {Blitze sind nach wie vor eine enorme Schadensquelle f{\"u}r Personensch{\"a}den, Br{\"a}nde, mechanische Zerst{\"o}rungen und insbesondere auch {\"U}berspannungen. Das zeigen nicht zuletzt aktuelle Statistiken der Schadensversicherer. Immer wieder gibt es Meldungen {\"u}ber extrem hohe Blitzstr{\"o}me, die nat{\"u}rlich auch zu großen Sch{\"a}den und Zerst{\"o}rungen f{\"u}hren k{\"o}nnen. Dabei werden Scheitelwerte von teilweise deutlich {\"u}ber 300 kA genannt. Dies wirft Fragen auf, da die „klassische" Blitzstatistik (z. B. nach CIGRE und IEC [8][10]) bisher solche Werte nicht kennt. Diese extremen Blitzstr{\"o}me werden meist aus den Daten von Blitzortungssystemen ermittelt.}, language = {de} } @article{KellerRathBruckmannetal.2020, author = {Keller, Johannes and Rath, Volker and Bruckmann, Johanna and Mottaghy, Darius and Clauser, Christoph and Wolf, Andreas and Seidler, Ralf and B{\"u}cker, H. Martin and Klitzsch, Norbert}, title = {SHEMAT-Suite: An open-source code for simulating flow, heat and species transport in porous media}, series = {SoftwareX}, volume = {12}, journal = {SoftwareX}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-7110}, doi = {10.1016/j.softx.2020.100533}, pages = {9}, year = {2020}, abstract = {SHEMAT-Suite is a finite-difference open-source code for simulating coupled flow, heat and species transport in porous media. The code, written in Fortran-95, originates from geoscientific research in the fields of geothermics and hydrogeology. It comprises: (1) a versatile handling of input and output, (2) a modular framework for subsurface parameter modeling, (3) a multi-level OpenMP parallelization, (4) parameter estimation and data assimilation by stochastic approaches (Monte Carlo, Ensemble Kalman filter) and by deterministic Bayesian approaches based on automatic differentiation for calculating exact (truncation error-free) derivatives of the forward code.}, language = {en} } @article{NobisSchmittSchemmetal.2020, author = {Nobis, Moritz and Schmitt, Carlo and Schemm, Ralf and Schnettler, Armin}, title = {Pan-European CVAR-constrained stochastic unit commitment in day-ahead and intraday electricity markets}, series = {Energies}, volume = {13}, journal = {Energies}, number = {Art. 2339}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en13092339}, pages = {1 -- 35}, year = {2020}, abstract = {The fundamental modeling of energy systems through individual unit commitment decisions is crucial for energy system planning. However, current large-scale models are not capable of including uncertainties or even risk-averse behavior arising from forecasting errors of variable renewable energies. However, risks associated with uncertain forecasting errors have become increasingly relevant within the process of decarbonization. The intraday market serves to compensate for these forecasting errors. Thus, the uncertainty of forecasting errors results in uncertain intraday prices and quantities. Therefore, this paper proposes a two-stage risk-constrained stochastic optimization approach to fundamentally model unit commitment decisions facing an uncertain intraday market. By the nesting of Lagrangian relaxation and an extended Benders decomposition, this model can be applied to large-scale, e.g., pan-European, power systems. The approach is applied to scenarios for 2023—considering a full nuclear phase-out in Germany—and 2035—considering a full coal phase-out in Germany. First, the influence of the risk factors is evaluated. Furthermore, an evaluation of the market prices shows an increase in price levels as well as an increasing day-ahead-intraday spread in 2023 and in 2035. Finally, it is shown that intraday cross-border trading has a significant influence on trading volumes and prices and ensures a more efficient allocation of resources.}, language = {en} } @article{HeelDiktaBraekers2021, author = {Heel, Mareike van and Dikta, Gerhard and Braekers, Roel}, title = {Bootstrap based goodness‑of‑fit tests for binary multivariate regression models}, series = {Journal of the Korean Statistical Society}, volume = {51}, journal = {Journal of the Korean Statistical Society}, publisher = {Springer Nature}, address = {Singapur}, issn = {2005-2863 (Online)}, doi = {10.1007/s42952-021-00142-4}, pages = {28 Seiten}, year = {2021}, abstract = {We consider a binary multivariate regression model where the conditional expectation of a binary variable given a higher-dimensional input variable belongs to a parametric family. Based on this, we introduce a model-based bootstrap (MBB) for higher-dimensional input variables. This test can be used to check whether a sequence of independent and identically distributed observations belongs to such a parametric family. The approach is based on the empirical residual process introduced by Stute (Ann Statist 25:613-641, 1997). In contrast to Stute and Zhu's approach (2002) Stute \& Zhu (Scandinavian J Statist 29:535-545, 2002), a transformation is not required. Thus, any problems associated with non-parametric regression estimation are avoided. As a result, the MBB method is much easier for users to implement. To illustrate the power of the MBB based tests, a small simulation study is performed. Compared to the approach of Stute \& Zhu (Scandinavian J Statist 29:535-545, 2002), the simulations indicate a slightly improved power of the MBB based method. Finally, both methods are applied to a real data set.}, 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{DellmannGloriusLitvinovetal.2023, author = {Dellmann, Sophia Florence and Glorius, J. and Litvinov, Yu A. and Reifarth, R. and Al-Khasawneh, Kafa and Aliotta, M. and Bott, L. and Br{\"u}ckner, Benjamin and Bruno, C. G. and Chen, Ruijiu and Davinson, T. and Dickel, T. and Dillmann, Iris and Dmytriev, D. and Erbacher, P. and Freire-Fern{\´a}ndez, D. and Forstner, Oliver and Geissel, H. and G{\"o}bel, K. and Griffin, Christopher J. and Grisenti, R. and Gumberidze, Alexandre and Haettner, Emma and Hagmann, Siegbert and Heil, M. and Heß, R. and Hillenbrand, P.-M. and Joseph, R. and Jurado, B. and Kozhuharov, Christophor and Kulikov, I. and L{\"o}her, Bastian and Langer, Christoph and Leckenby, Guy and Lederer-Woods, C. and Lestinsky, M. and Litvinov, S. A. and Lorenz, B. A. and Lorenz, E. and Marsh, J. and Menz, Esther Babette and Morgenroth, T. and Petridis, N. and Pibernat, Jerome and Popp, U. and Psaltis, Athanasios and Sanjari, Shahab and Scheidenberger, C. and Sguazzin, M. and Sidhu, Ragandeep Singh and Spillmann, Uwe and Steck, M. and St{\"o}hlker, T. and Surzhykov, A. and Swartz, J. A. and T{\"o}rnqvist, H. and Varga, L. and Vescovi, Diego and Weick, H. and Weigand, M. and Woods, P. and Xing, Y. and Yamaguchi, Taiyo}, title = {Proton capture on stored radioactive ¹¹⁸Te ions}, series = {EPJ Web of Conferences}, volume = {279}, journal = {EPJ Web of Conferences}, number = {Article Number: 11018}, publisher = {EDP Sciences}, issn = {2100-014X}, doi = {10.1051/epjconf/202327911018}, pages = {1 -- 5}, year = {2023}, abstract = {Experimental determination of the cross sections of proton capture on radioactive nuclei is extremely difficult. Therefore, it is of substantial interest for the understanding of the production of the p-nuclei. For the first time, a direct measurement of proton-capture cross sections on stored, radioactive ions became possible in an energy range of interest for nuclear astrophysics. The experiment was performed at the Experimental Storage Ring (ESR) at GSI by making use of a sensitive method to measure (p,γ) and (p,n) reactions in inverse kinematics. These reaction channels are of high relevance for the nucleosyn-thesis processes in supernovae, which are among the most violent explosions in the universe and are not yet well understood. The cross section of the ¹¹⁸Te(p,γ) reaction has been measured at energies of 6 MeV/u and 7 MeV/u. The heavy ions interacted with a hydrogen gas jet target. The radiative recombination process of the fully stripped ¹¹⁸Te ions and electrons from the hydrogen target was used as a luminosity monitor. An overview of the experimental method and preliminary results from the ongoing analysis will be presented.}, language = {en} } @article{AlexopoulosHoffschmidt2017, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard}, title = {Advances in solar tower technology}, series = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, volume = {6}, journal = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2041-840X}, doi = {10.1002/wene.217}, pages = {1 -- 19}, year = {2017}, language = {en} } @article{IlleSchrammAdametal.2008, author = {Ille, F. and Schramm, S. and Adam, M. and Backes, K. and Faber, Christian and Anthrakidis, Anette}, title = {Kraft-W{\"a}rme-K{\"a}lte-Kopplung im Leistungsbereich von 10 kW mit periodisch arbeitender Sorptionsmaschine}, series = {VDI-Tage der Geb{\"a}udetechnik 2008 : Tagung Dortmund, 28. und 29. Mai 2008 / VDI-Gesellschaft Technische Geb{\"a}udeausr{\"u}stung}, journal = {VDI-Tage der Geb{\"a}udetechnik 2008 : Tagung Dortmund, 28. und 29. Mai 2008 / VDI-Gesellschaft Technische Geb{\"a}udeausr{\"u}stung}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, isbn = {978-3-18-092043-6}, pages = {103 -- 116}, year = {2008}, language = {de} } @article{AlexopoulosBreitbachHoffschmidtetal.2008, author = {Alexopoulos, Spiros and Breitbach, Gerd and Hoffschmidt, Bernhard and Stobbe, P.}, title = {Computational fluid flow of porous resic ceramic filtering modules and optimization of the channel edge form geometry}, series = {Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2}, journal = {Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2}, publisher = {Filtech Exhibitions}, address = {Meerbusch}, pages = {300 -- 304}, year = {2008}, language = {en} } @article{MaurerRiekeSchemmetal.2023, author = {Maurer, Florian and Rieke, Christian and Schemm, Ralf and Stollenwerk, Dominik}, title = {Analysis of an urban grid with high photovoltaic and e-mobility penetration}, series = {Energies}, volume = {16}, journal = {Energies}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en16083380}, pages = {18 Seiten}, year = {2023}, abstract = {This study analyses the expected utilization of an urban distribution grid under high penetration of photovoltaic and e-mobility with charging infrastructure on a residential level. The grid utilization and the corresponding power flow are evaluated, while varying the control strategies and photovoltaic installed capacity in different scenarios. Four scenarios are used to analyze the impact of e-mobility. The individual mobility demand is modelled based on the largest German studies on mobility "Mobilit{\"a}t in Deutschland", which is carried out every 5 years. To estimate the ramp-up of photovoltaic generation, a potential analysis of the roof surfaces in the supply area is carried out via an evaluation of an open solar potential study. The photovoltaic feed-in time series is derived individually for each installed system in a resolution of 15 min. The residential consumption is estimated using historical smart meter data, which are collected in London between 2012 and 2014. For a realistic charging demand, each residential household decides daily on the state of charge if their vehicle requires to be charged. The resulting charging time series depends on the underlying behavior scenario. Market prices and mobility demand are therefore used as scenario input parameters for a utility function based on the current state of charge to model individual behavior. The aggregated electricity demand is the starting point of the power flow calculation. The evaluation is carried out for an urban region with approximately 3100 residents. The analysis shows that increased penetration of photovoltaics combined with a flexible and adaptive charging strategy can maximize PV usage and reduce the need for congestion-related intervention by the grid operator by reducing the amount of kWh charged from the grid by 30\% which reduces the average price of a charged kWh by 35\% to 14 ct/kWh from 21.8 ct/kWh without PV optimization. The resulting grid congestions are managed by implementing an intelligent price or control signal. The analysis took place using data from a real German grid with 10 subgrids. The entire software can be adapted for the analysis of different distribution grids and is publicly available as an open-source software library on GitHub.}, language = {en} } @article{VerschitzButenweg2014, author = {Verschitz, Daniel and Butenweg, Christoph}, title = {Standsicherheitsnachweis von Beh{\"a}ltern f{\"u}r Kleinkl{\"a}ranlagen}, series = {ACWA aktuell}, journal = {ACWA aktuell}, number = {12 - 9/2014}, publisher = {RWTH Aachen}, address = {Aachen}, pages = {10}, year = {2014}, abstract = {Die PIA GmbH pr{\"u}ft seit fast 8 Jahren die Standsicherheit von Beh{\"a}ltern f{\"u}r Kleinkl{\"a}ranlagen. Diese bestehen in der Regel aus Kunststoff oder Beton und m{\"u}ssen {\"u}ber ihre gesamte Lebensdauer den Beanspruchungen aus Handhabung, Einbau und Betrieb standhalten. Die Standsicherheit kann nach EN 12566 wahlweise durch einen rechnerischen Nachweis oder durch einen praktischen Nachweis wie die Bruchlastpr{\"u}fung oder die Pr{\"u}fung in der Grube erfolgen.}, language = {de} } @article{MykoniouButenwegHoltschoppenetal.2016, author = {Mykoniou, Konstantin and Butenweg, Christoph and Holtschoppen, Britta and Klinkel, Sven}, title = {Seismic response analysis of adjacent liquid-storage tanks}, series = {Earthquake engineering and structural dynamics}, volume = {45}, journal = {Earthquake engineering and structural dynamics}, number = {11}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1096-9845 (E-Journal); 0098-8847 (Print)}, doi = {10.1002/eqe.2726}, pages = {1779 -- 1796}, year = {2016}, abstract = {A refined substructure technique in the frequency domain is developed, which permits consideration of the interaction effects among adjacent containers through the supporting deformable soil medium. The tank-liquid systems are represented by means of mechanical models, whereas discrete springs and dashpots stand for the soil beneath the foundations. The proposed model is employed to assess the responses of adjacent circular, cylindrical tanks for harmonic and seismic excitations over wide range of tank proportions and soil conditions. The influence of the number, spatial arrangement of the containers and their distance on the overall system's behavior is addressed. The results indicate that the cross-interaction effects can substantially alter the impulsive components of response of each individual element in a tank farm. The degree of this impact is primarily controlled by the tank proportions and the proximity of the predominant natural frequencies of the shell-liquid-soil systems and the input seismic motion. The group effects should be not a priori disregarded, unless the tanks are founded on shallow soil deposit overlying very stiff material or bedrock.}, language = {en} } @article{TaddeiButenwegKlinkel2015, author = {Taddei, Francesca and Butenweg, Christoph and Klinkel, S.}, title = {Parametric investigation of the soil-structure interaction effects on the dynamic behaviour of a shallow foundation supported wind turbine considering a layered soil}, series = {Wind energy : an international journal for progress and applications in wind power conversion technology}, volume = {Volume 18}, journal = {Wind energy : an international journal for progress and applications in wind power conversion technology}, number = {Issue 3}, publisher = {Wiley}, address = {Weinheim}, issn = {1099-1824 (E-Journal); 1095-4244 (Print)}, doi = {10.1002/we.1703}, pages = {399 -- 417}, year = {2015}, language = {en} } @article{AltayButenwegTaddei2013, author = {Altay, Okyay and Butenweg, Christoph and Taddei, Francesca}, title = {Effektivit{\"a}t von Schwingungsd{\"a}mpfern bei Windenergieanlagen}, series = {Bauingenieur : die richtungsweisende Zeitschrift im Bauingenieurswesen ; offizielle Zeitschrift der VDI-Gesellschaft Bautechnik. Beilage: D-A-CH-Mitteilungsblatt}, volume = {Band 88}, journal = {Bauingenieur : die richtungsweisende Zeitschrift im Bauingenieurswesen ; offizielle Zeitschrift der VDI-Gesellschaft Bautechnik. Beilage: D-A-CH-Mitteilungsblatt}, number = {Heft 10}, publisher = {VDI Fachmedien}, address = {D{\"u}sseldorf}, issn = {1436-4867 (E-Journal); 0005-6650 (Print)}, pages = {S11 -- S17}, year = {2013}, language = {de} } @article{ButenwegKleemannIkier2013, author = {Butenweg, Christoph and Kleemann, Anne and Ikier, Axel}, title = {Impact-Belastungen von Stahlbetonkonstruktionen}, series = {Bauingenieur : die richtungsweisende Zeitschrift im Bauingenieurswesen ; offizielle Zeitschrift der VDI-Gesellschaft Bautechnik. Beilage: D-A-CH-Mitteilungsblatt}, volume = {Band 88}, journal = {Bauingenieur : die richtungsweisende Zeitschrift im Bauingenieurswesen ; offizielle Zeitschrift der VDI-Gesellschaft Bautechnik. Beilage: D-A-CH-Mitteilungsblatt}, publisher = {VDI Verlag}, address = {D{\"u}sseldorf}, issn = {0005-6650}, pages = {S7 -- S14}, year = {2013}, language = {de} } @article{KubalskiButenweg2015, author = {Kubalski, Thomas and Butenweg, Christoph}, title = {Modelling strategies for horizontally loaded infill masonry}, series = {Mauerwerk : European journal of masonry}, volume = {Volume 19}, journal = {Mauerwerk : European journal of masonry}, number = {Issue 5}, publisher = {Wiley}, address = {Weinheim}, doi = {10.1002/dama.201500675}, pages = {363 -- 369}, year = {2015}, language = {de} } @article{ButenwegGellert2013, author = {Butenweg, Christoph and Gellert, Christoph}, title = {Nichtlinearer Nachweis von Mauerwerksbauten}, series = {Mauerwerk : European journal of masonry}, volume = {Volume 17}, journal = {Mauerwerk : European journal of masonry}, number = {Issue 3}, publisher = {Wiley}, address = {Weinheim}, issn = {1437-1022 (E-Journal); 1432-3427 (Print)}, doi = {10.1002/dama.201300575}, pages = {166 -- 171}, year = {2013}, language = {de} } @article{MeskourisButenwegRenault2006, author = {Meskouris, Konstantin and Butenweg, Christoph and Renault, Philippe}, title = {Beurteilung der Erdbebensicherheit von bestehenden Bauwerken}, series = {Der Pr{\"u}fingenieur : das Magazin der Bundesvereinigung der Pr{\"u}fingenieure f{\"u}r Bautechnik}, journal = {Der Pr{\"u}fingenieur : das Magazin der Bundesvereinigung der Pr{\"u}fingenieure f{\"u}r Bautechnik}, number = {Ausgabe 28}, issn = {1430-9084}, pages = {56 -- 65}, year = {2006}, language = {de} } @article{HollerButenwegNohetal.2004, author = {Holler, S. and Butenweg, Christoph and Noh, S.-Y. and Meskouris, Konstantin}, title = {Computational model of textile-reinforced concrete structures}, series = {Computers \& structures : an international journal}, volume = {Volume 82}, journal = {Computers \& structures : an international journal}, number = {Issues 23-26}, issn = {1879-2243 (E-Journal); 0045-7949 (Print)}, doi = {10.1016/j.compstruc.2004.03.076}, pages = {1971 -- 1979}, year = {2004}, language = {en} } @article{RenaultButenwegMeskouris2005, author = {Renault, Philippe and Butenweg, Christoph and Meskouris, Konstantin}, title = {Beurteilung der Erdbebensicherheit von bestehenden Br{\"u}ckenbauwerken am Beispiel der Rheinbr{\"u}cke Emmerich}, series = {Beton- und Stahlbetonbau}, volume = {Volume 100}, journal = {Beton- und Stahlbetonbau}, number = {Issue 7}, issn = {1437-1006 (E-Journal); 0005-9900 (Print)}, doi = {10.1002/best.200590145}, pages = {574 -- 581}, year = {2005}, language = {de} } @article{MistlerButenweg2005, author = {Mistler, Michael and Butenweg, Christoph}, title = {Verformungsbasierter seismischer Nachweis von Mauerwerksbauten mit der Kapazit{\"a}tsspektrum-Methode}, series = {Mauerwerk : European journal of masonry}, volume = {Volume 9}, journal = {Mauerwerk : European journal of masonry}, number = {Issue 6}, issn = {1437-1022 (E-Journal); 1432-3427 (Print)}, doi = {10.1002/dama.200590098}, pages = {255 -- 261}, year = {2005}, language = {de} }