@phdthesis{Gaigall2016, author = {Gaigall, Daniel}, title = {Vergleich von statistischen Tests im verbundenen und unabh{\"a}ngigen Stichprobenfall}, publisher = {Gottfried Wilhelm Leibniz Universit{\"a}t Hannover}, address = {Hannover}, doi = {10.15488/8678}, pages = {281 Seiten}, year = {2016}, abstract = {Es werden Effizienzbegriffe zum Vergleich von statistischen Tests basierend auf verschiedenen statistischen Experimenten eingef{\"u}hrt. Dabei handelt es sich um die schon aus dem Vergleich von statistischen Tests in je demselben Modell bekannten asymptotischen relativen Effizienzen wie die Hodges-Lehmann-Effizienz, die Bahadur-Effizienz und die Pitman-Effizienz sowie um Kriterien basierend auf Volumina von Konfidenzbereichen. Effizienzaussagen werden unter anderem f{\"u}r Likelihood-Quotienten-Tests und Waldsche Tests im Rahmen eines allgemeinen multivariaten parametrischen Modells erhalten. Statistische Tests zur Pr{\"u}fung von Hypothesen {\"u}ber die relative Wirksamkeit zweier Experimente werden vorgeschlagen. Auf der Grundlage der erhaltenen Ergebnisse erfolgt ein Vergleich der Wirksamkeit von korrespondierenden Verfahren bei verbundener Stichprobenerhebung und unabh{\"a}ngiger Stichprobenerhebung. Die Rolle der Kovarianzmatrix bei verbundener Stichprobenerhebung wird insbesondere unter der Annahme, dass die zugrunde liegenden Verteilungen durch k-parametrische Exponentialfamilien modellierbar sind, herausgearbeitet. Verbindungen zu Effizienzbegriffen bei Punkt- und Konfidenzbereichssch{\"a}tzverfahren werden aufgezeigt. Ausf{\"u}hrlichere Untersuchungen betreffen die korrespondierenden Hotellingschen T²-Tests im multivariaten Normalverteilungsfall, die klassischen Homogenitatstests bei k × k-Kontingenztafeln und die Wilcoxon Tests in nichtparametrischen Lagealternativmodellen}, language = {de} } @article{ButenwegKubalskiElDeibetal.2021, author = {Butenweg, Christoph and Kubalski, Thomas and El-Deib, Khaled and Gellert, Christoph}, title = {Erdbebennachweis von Mauerwerksbauten nach DIN EN 1998-1/NA-2021}, series = {Bautechnik : Zeitschrift f{\"u}r den gesamten Ingenieurbau}, volume = {98}, journal = {Bautechnik : Zeitschrift f{\"u}r den gesamten Ingenieurbau}, number = {11}, editor = {Jesse, Dirk}, publisher = {Ernst \& Sohn}, address = {Berlin}, issn = {1437-0999}, doi = {10.1002/bate.202100064}, pages = {852 -- 863}, year = {2021}, abstract = {Mauerwerksbauten in Deutschland sind mit Einf{\"u}hrung des nationalen Anwendungsdokuments DIN EN 1998-1/NA auf Grundlage einer neuen probabilistischen Erdbebenkarte nachzuweisen. F{\"u}r erfolgreiche Erdbebennachweise {\"u}blicher Grundrissformen von Mauerwerksbauten stehen in dem zuk{\"u}nftigen Anwendungsdokument neue rechnerische Nachweism{\"o}glichkeiten zur Verf{\"u}gung, mit denen die Tragf{\"a}higkeitsreserven von Mauerwerksbauten in der Baupraxis mit einem {\"u}berschaubaren Aufwand besser in Ansatz gebracht werden k{\"o}nnen. Das Standardrechenverfahren ist weiterhin der kraftbasierte Nachweis, der nun mit h{\"o}heren Verhaltensbeiwerten im Vergleich zur DIN 4149 durchgef{\"u}hrt werden kann. Die h{\"o}heren Verhaltensbeiwerte basieren auf der besseren Ausnutzung der geb{\"a}udespezifischen Verformungsf{\"a}higkeit und Energiedissipation sowie der Lastumverteilung der Schubkr{\"a}fte im Grundriss mit Ansatz von Rahmentragwirkung durch Wand-Deckeninteraktionen. Alternativ dazu kann ein nichtlinearer Nachweis auf Grundlage von Pushover-Analysen zur Anwendung kommen. Vervollst{\"a}ndigt werden die Regelungen f{\"u}r Mauerwerksbauten durch neue Regelungen f{\"u}r nichttragende Innenw{\"a}nde und Außenmauerschalen. Der vorliegende Beitrag stellt die Grundlagen und Hintergr{\"u}nde der neuen rechnerischen Nachweise in DIN EN 1998-1/NA vor und demonstriert deren Anwendung an einem Beispiel aus der Praxis.}, language = {de} } @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{ElDeibButenwegKlinkel2021, author = {El-Deib, Khaled and Butenweg, Christoph and Klinkel, Sven}, title = {Erdbebennachweis von Mauerwerksbauten mit realistischen Modellen und erh{\"o}hten Verhaltensbeiwerten}, series = {Mauerwerk}, volume = {2021}, journal = {Mauerwerk}, number = {3}, editor = {Jesse, Dirk}, publisher = {Wiley}, address = {Weinheim}, issn = {1437-1022}, doi = {10.1002/dama.202110014}, pages = {110 -- 119}, year = {2021}, abstract = {Die Anwendung des linearen Nachweiskonzepts auf Mauerwerksbauten f{\"u}hrt dazu, dass bereits heute Standsicherheitsnachweise f{\"u}r Geb{\"a}ude mit {\"u}blichen Grundrissen in Gebieten mit moderaten Erdbebeneinwirkungen nicht mehr gef{\"u}hrt werden k{\"o}nnen. Diese Problematik wird sich in Deutschland mit der Einf{\"u}hrung kontinuierlicher probabilistischer Erdbebenkarten weiter versch{\"a}rfen. Aufgrund der Erh{\"o}hung der seismischen Einwirkungen, die sich vielerorts ergibt, ist es erforderlich, die vorhandenen, bislang nicht ber{\"u}cksichtigten Tragf{\"a}higkeitsreserven in nachvollziehbaren Nachweiskonzepten in der Baupraxis verf{\"u}gbar zu machen. Der vorliegende Beitrag stellt ein Konzept f{\"u}r die geb{\"a}udespezifische Ermittlung von erh{\"o}hten Verhaltensbeiwerten vor. Die Verhaltensbeiwerte setzen sich aus drei Anteilen zusammen, mit denen die Lastumverteilung im Grundriss, die Verformungsf{\"a}higkeit und Energiedissipation sowie die {\"U}berfestigkeiten ber{\"u}cksichtigt werden. F{\"u}r die rechnerische Ermittlung dieser drei Anteile wird ein nichtlineares Nachweiskonzept auf Grundlage von Pushover-Analysen vorgeschlagen, in denen die Interaktionen von W{\"a}nden und Geschossdecken durch einen Einspanngrad beschrieben werden. F{\"u}r die Bestimmung der Einspanngrade wird ein nichtlinearer Modellierungsansatz eingef{\"u}hrt, mit dem die Interaktion von W{\"a}nden und Decken abgebildet werden kann. Die Anwendung des Konzepts mit erh{\"o}hten geb{\"a}udespezifischen Verhaltensbeiwerten wird am Beispiel eines Mehrfamilienhauses aus Kalksandsteinen demonstriert. Die Ergebnisse der linearen Nachweise mit erh{\"o}hten Verhaltensbeiwerten f{\"u}r dieses Geb{\"a}ude liegen deutlich n{\"a}her an den Ergebnissen nichtlinearer Nachweise und somit bleiben {\"u}bliche Grundrisse in Erdbebengebieten mit den traditionellen linearen Rechenans{\"a}tzen nachweisbar.}, language = {de} } @article{MarinkovićButenweg2022, author = {Marinković, Marko and Butenweg, Christoph}, title = {Experimental testing of decoupled masonry infills with steel anchors for out-of-plane support under combined in-plane and out-of-plane seismic loading}, series = {Construction and Building Materials}, volume = {318}, journal = {Construction and Building Materials}, number = {1}, editor = {Ford, Michael C.}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-0526}, doi = {10.1016/j.conbuildmat.2021.126041}, year = {2022}, abstract = {Because of simple construction process, high energy efficiency, significant fire resistance and excellent sound isolation, masonry infilled reinforced concrete (RC) frame structures are very popular in most of the countries in the world, as well as in seismic active areas. However, many RC frame structures with masonry infills were seriously damaged during earthquake events, as the traditional infills are generally constructed with direct contact to the RC frame which brings undesirable infill/frame interaction. This interaction leads to the activation of the equivalent diagonal strut in the infill panel, due to the RC frame deformation, and combined with seismically induced loads perpendicular to the infill panel often causes total collapses of the masonry infills and heavy damages to the RC frames. This fact was the motivation for developing different approaches for improving the behaviour of masonry infills, where infill isolation (decoupling) from the frame has been more intensively studied in the last decade. In-plane isolation of the infill wall reduces infill activation, but causes the need for additional measures to restrain out-of-plane movements. This can be provided by installing steel anchors, as proposed by some researchers. Within the framework of European research project INSYSME (Innovative Systems for Earthquake Resistant Masonry Enclosures in Reinforced Concrete Buildings) the system based on a use of elastomers for in-plane decoupling and steel anchors for out-of-plane restrain was tested. This constructive solution was tested and deeply investigated during the experimental campaign where traditional and decoupled masonry infilled RC frames with anchors were subjected to separate and combined in-plane ‬and out-of-plane loading. Based on a detailed evaluation and comparison of the test results, the performance and effectiveness of the developed system are illustrated.}, language = {en} } @article{Timme2022, author = {Timme, Michael}, title = {Beweislast beim gutgl{\"a}ubigen Erwerb eines Kraftfahrzeugs ohne Erhalt der Zulassungsbescheinigung Teil II — Zugleich eine Besprechung von BGH, Urt. v. 23.9.2022 - V ZR 148/21, MDR 2022, 1542}, series = {Monatsschrift f{\"u}r Deutsches Recht}, volume = {77}, journal = {Monatsschrift f{\"u}r Deutsches Recht}, number = {1}, publisher = {Verlag Dr. Otto Schmidt}, address = {K{\"o}ln}, issn = {0340-1812}, doi = {doi.org/10.9785/mdtr-2023-770102}, pages = {r5 -- r7}, year = {2022}, abstract = {Im Handel mit Kraftfahrzeugen geh{\"o}ren Aspekte des gutgl{\"a}ubigen Erwerbs zu den beinahe allt{\"a}glichen Standardproblemen. Der BGH f{\"u}gt in seiner Entscheidung v. 23.9.2022-VZR148/21, MDR 2022, 1541 diesem im Detail breit gef{\"a}cherten Themenfeld einen weiteren Mosaikstein hinzu: Der Erwerber erhielt das verkaufte Kfz ohne {\"U}bergabe einer Zulassungsbescheinigung Teil II, behauptet aber, diese Bescheinigung sei dem vom ihm eingeschalteten Vermittler bei Erwerb (als F{\"a}lschung) vorgelegt worden. Tats{\"a}chlich befand sich das Original durchg{\"a}ngig beim wahren Eigent{\"u}mer, der nunmehr Herausgabe des Fahrzeugs verlangt. Der BGH sch{\"u}tzt in dieser Gestaltung im Ergebnis den Erwerber. Die Entscheidung ist in mehrfacher Hinsicht bemerkenswert.}, language = {de} } @misc{ButenwegGellertReindletal.2009, author = {Butenweg, Christoph and Gellert, Christoph and Reindl, Lukas and Meskouris, Konstantin}, title = {A nonlinear method for the seismic safety verification of masonry buildings}, publisher = {National Technical University of Athens}, address = {Athen}, year = {2009}, abstract = {In order for traditional masonry to stay a competitive building material in seismically active regions there is an urgent demand for modern, deformation-based verification procedures which exploit the nonlinear load bearing reserves. The Capacity Spectrum Method (CSM) is a widely accepted design approach in the field of reinforced concrete and steel construction. It compares the seismic action with the load-bearing capacity of the building considering nonlinear material behavior with its post-peak capacity. The bearing capacity of the building is calculated iteratively using single wall capacity curves. This paper presents a new approach for the bilinear approximation of single wall capacity curves in the style of EC6/EC8 respectively FEMA 306/FEMA 356 based on recent shear wall test results of the European Collective-Research Project "ESECMaSE". The application of the CSM to masonry structures by using bilinear approximations of capacity curves as input is demonstrated on the example of a typical German residential home.}, language = {en} } @inproceedings{RosinKubalskiButenweg2013, author = {Rosin, Julia and Kubalski, Thomas and Butenweg, Christoph}, title = {Seismic isolation of cylindrical liquid storage tanks}, series = {Seismic design of industrial facilities}, booktitle = {Seismic design of industrial facilities}, editor = {Klinkel, Sven and Butenweg, Christoph and Lin, Gao and Holtschoppen, Britta}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {978-3-658-02810-7}, doi = {10.1007/978-3-658-02810-7_36}, pages = {429 -- 440}, year = {2013}, abstract = {Seismic excited liquid filled tanks are subjected to extreme loading due to hydrodynamic pressures, which can lead to nonlinear stability failure of the thinwalled cylindrical tanks, as it is known from past earthquakes. A significant reduction of the seismically induced loads can be obtained by the application of base isolation systems, which have to be designed carefully with respect to the modified hydrodynamic behaviour of the tank in interaction with the liquid. For this reason a highly sophisticated fluid-structure interaction model has to be applied for a realistic simulation of the overall dynamic system. In the following, such a model is presented and compared with the results of simplified mathematical models for rigidly supported tanks. Finally, it is examined to what extent a simple mechanical model can represent the behaviour of a base isolated tank in case of seismic excitation}, language = {en} } @article{NiedermeierPennerUsherovichetal.2023, author = {Niedermeier, Jana and Penner, Crystal and Usherovich, Samuel and B{\´e}langer-Champagne, Camille and Paulßen, Elisabeth and Hoehr, Cornelia}, title = {Optical Fibers as Dosimeter Detectors for Mixed Proton/Neutron Fields - A Biological Dosimeter}, series = {electronics}, volume = {12}, journal = {electronics}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {10.3390/electronics12020324}, pages = {11 Seiten}, year = {2023}, abstract = {In recent years, proton therapy has gained importance as a cancer treatment modality due to its conformality with the tumor and the sparing of healthy tissue. However, in the interaction of the protons with the beam line elements and patient tissues, potentially harmful secondary neutrons are always generated. To ensure that this neutron dose is as low as possible, treatment plans could be created to also account for and minimize the neutron dose. To monitor such a treatment plan, a compact, easy to use, and inexpensive dosimeter must be developed that not only measures the physical dose, but which can also distinguish between proton and neutron contributions. To that end, plastic optical fibers with scintillation materials (Gd₂O₂S:Tb, Gd₂O₂S:Eu, and YVO₄:Eu) were irradiated with protons and neutrons. It was confirmed that sensors with different scintillation materials have different sensitivities to protons and neutrons. A combination of these three scintillators can be used to build a detector array to create a biological dosimeter.}, language = {en} } @article{PennerUsherovichNiedermeieretal.2022, author = {Penner, Crystal and Usherovich, Samuel and Niedermeier, Jana and B{\´e}langer-Champagne, Camille and Trinczek, Michael and Paulßen, Elisabeth and Hoehr, Cornelia}, title = {Organic Scintillator-Fibre Sensors for Proton Therapy Dosimetry: SCSF-3HF and EJ-260}, series = {electronics}, volume = {12}, journal = {electronics}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {10.3390/electronics12010011}, pages = {12 Seiten}, year = {2022}, abstract = {In proton therapy, the dose from secondary neutrons to the patient can contribute to side effects and the creation of secondary cancer. A simple and fast detection system to distinguish between dose from protons and neutrons both in pretreatment verification as well as potentially in vivo monitoring is needed to minimize dose from secondary neutrons. Two 3 mm long, 1 mm diameter organic scintillators were tested for candidacy to be used in a proton-neutron discrimination detector. The SCSF-3HF (1500) scintillating fibre (Kuraray Co. Chiyoda-ku, Tokyo, Japan) and EJ-260 plastic scintillator (Eljen Technology, Sweetwater, TX, USA) were irradiated at the TRIUMF Neutron Facility and the Proton Therapy Research Centre. In the proton beam, we compared the raw Bragg peak and spread-out Bragg peak response to the industry standard Markus chamber detector. Both scintillator sensors exhibited quenching at high LET in the Bragg peak, presenting a peak-to-entrance ratio of 2.59 for the EJ-260 and 2.63 for the SCSF-3HF fibre, compared to 3.70 for the Markus chamber. The SCSF-3HF sensor demonstrated 1.3 times the sensitivity to protons and 3 times the sensitivity to neutrons as compared to the EJ-260 sensor. Combined with our equations relating neutron and proton contributions to dose during proton irradiations, and the application of Birks' quenching correction, these fibres provide valid candidates for inexpensive and replicable proton-neutron discrimination detectors}, language = {en} }