@article{PourshahidiAchtsnichtOffenhaeusseretal.2022, author = {Pourshahidi, Ali Mohammad and Achtsnicht, Stefan and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim}, title = {Frequency Mixing Magnetic Detection Setup Employing Permanent Ring Magnets as a Static Offset Field Source}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {22}, editor = {Offenh{\"a}usser, Andreas}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s22228776}, pages = {12 Seiten}, year = {2022}, abstract = {Frequency mixing magnetic detection (FMMD) has been explored for its applications in fields of magnetic biosensing, multiplex detection of magnetic nanoparticles (MNP) and the determination of core size distribution of MNP samples. Such applications rely on the application of a static offset magnetic field, which is generated traditionally with an electromagnet. Such a setup requires a current source, as well as passive or active cooling strategies, which directly sets a limitation based on the portability aspect that is desired for point of care (POC) monitoring applications. In this work, a measurement head is introduced that involves the utilization of two ring-shaped permanent magnets to generate a static offset magnetic field. A steel cylinder in the ring bores homogenizes the field. By variation of the distance between the ring magnets and of the thickness of the steel cylinder, the magnitude of the magnetic field at the sample position can be adjusted. Furthermore, the measurement setup is compared to the electromagnet offset module based on measured signals and temperature behavior.}, language = {en} } @article{PoghossianKarschuckWagneretal.2022, author = {Poghossian, Arshak and Karschuck, Tobias and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Field-Effect Capacitors Decorated with Ligand-Stabilized Gold Nanoparticles: Modeling and Experiments}, series = {Biosensors}, volume = {12}, journal = {Biosensors}, number = {5}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios12050334}, pages = {Artikel 334}, year = {2022}, abstract = {Nanoparticles are recognized as highly attractive tunable materials for designing field-effect biosensors with enhanced performance. In this work, we present a theoretical model for electrolyte-insulator-semiconductor capacitors (EISCAP) decorated with ligand-stabilized charged gold nanoparticles. The charged AuNPs are taken into account as additional, nanometer-sized local gates. The capacitance-voltage (C-V) curves and constant-capacitance (ConCap) signals of the AuNP-decorated EISCAPs have been simulated. The impact of the AuNP coverage on the shift of the C-V curves and the ConCap signals was also studied experimentally on Al-p-Si-SiO₂ EISCAPs decorated with positively charged aminooctanethiol-capped AuNPs. In addition, the surface of the EISCAPs, modified with AuNPs, was characterized by scanning electron microscopy for different immobilization times of the nanoparticles.}, language = {en} } @article{VahidpourAlghazaliAkcaetal.2022, author = {Vahidpour, Farnoosh and Alghazali, Yousef and Akca, Sevilay and Hommes, Gregor and Sch{\"o}ning, Michael Josef}, title = {An Enzyme-Based Interdigitated Electrode-Type Biosensor for Detecting Low Concentrations of H₂O₂ Vapor/Aerosol}, series = {Chemosensors}, volume = {10}, journal = {Chemosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2227-9040}, doi = {10.3390/chemosensors10060202}, pages = {Arikel 202}, year = {2022}, abstract = {This work introduces a novel method for the detection of H₂O₂ vapor/aerosol of low concentrations, which is mainly applied in the sterilization of equipment in medical industry. Interdigitated electrode (IDE) structures have been fabricated by means of microfabrication techniques. A differential setup of IDEs was prepared, containing an active sensor element (active IDE) and a passive sensor element (passive IDE), where the former was immobilized with an enzymatic membrane of horseradish peroxidase that is selective towards H₂O₂. Changes in the IDEs' capacitance values (active sensor element versus passive sensor element) under H₂O₂ vapor/aerosol atmosphere proved the detection in the concentration range up to 630 ppm with a fast response time (<60 s). The influence of relative humidity was also tested with regard to the sensor signal, showing no cross-sensitivity. The repeatability assessment of the IDE biosensors confirmed their stable capacitive signal in eight subsequent cycles of exposure to H₂O₂ vapor/aerosol. Room-temperature detection of H₂O₂ vapor/aerosol with such miniaturized biosensors will allow a future three-dimensional, flexible mapping of aseptic chambers and help to evaluate sterilization assurance in medical industry.}, language = {en} } @article{HoffmannUhlCeblinetal.2022, author = {Hoffmann, Andreas and Uhl, Matthias and Ceblin, Maximilian and Rohrbach, Felix and Bansmann, Joachim and Mallah, Marcel and Heuermann, Holger and Jacob, Timo and Kuehne, Alexander J.C.}, title = {Atmospheric pressure plasma-jet treatment of PAN-nonwovens—carbonization of nanofiber electrodes}, series = {C - Journal of Carbon Research}, volume = {8}, journal = {C - Journal of Carbon Research}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2311-5629}, doi = {10.3390/c8030033}, pages = {8 Seiten}, year = {2022}, abstract = {Carbon nanofibers are produced from dielectric polymer precursors such as polyacrylonitrile (PAN). Carbonized nanofiber nonwovens show high surface area and good electrical conductivity, rendering these fiber materials interesting for application as electrodes in batteries, fuel cells, and supercapacitors. However, thermal processing is slow and costly, which is why new processing techniques have been explored for carbon fiber tows. Alternatives for the conversion of PAN-precursors into carbon fiber nonwovens are scarce. Here, we utilize an atmospheric pressure plasma jet to conduct carbonization of stabilized PAN nanofiber nonwovens. We explore the influence of various processing parameters on the conductivity and degree of carbonization of the converted nanofiber material. The precursor fibers are converted by plasma-jet treatment to carbon fiber nonwovens within seconds, by which they develop a rough surface making subsequent surface activation processes obsolete. The resulting carbon nanofiber nonwovens are applied as supercapacitor electrodes and examined by cyclic voltammetry and impedance spectroscopy. Nonwovens that are carbonized within 60 s show capacitances of up to 5 F g⁻¹.}, language = {en} } @article{AkimbekovDigelTastambeketal.2022, author = {Akimbekov, Nuraly S. and Digel, Ilya and Tastambek, Kuanysh T. and Marat, Adel K. and Turaliyeva, Moldir A. and Kaiyrmanova, Gulzhan K.}, title = {Biotechnology of Microorganisms from Coal Environments: From Environmental Remediation to Energy Production}, series = {Biology}, volume = {11}, journal = {Biology}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2079-7737}, doi = {10.3390/biology11091306}, pages = {47 Seiten}, year = {2022}, abstract = {It was generally believed that coal sources are not favorable as live-in habitats for microorganisms due to their recalcitrant chemical nature and negligible decomposition. However, accumulating evidence has revealed the presence of diverse microbial groups in coal environments and their significant metabolic role in coal biogeochemical dynamics and ecosystem functioning. The high oxygen content, organic fractions, and lignin-like structures of lower-rank coals may provide effective means for microbial attack, still representing a greatly unexplored frontier in microbiology. Coal degradation/conversion technology by native bacterial and fungal species has great potential in agricultural development, chemical industry production, and environmental rehabilitation. Furthermore, native microalgal species can offer a sustainable energy source and an excellent bioremediation strategy applicable to coal spill/seam waters. Additionally, the measures of the fate of the microbial community would serve as an indicator of restoration progress on post-coal-mining sites. This review puts forward a comprehensive vision of coal biodegradation and bioprocessing by microorganisms native to coal environments for determining their biotechnological potential and possible applications.}, language = {en} } @article{SchulteTiggesFoersterNikolovskietal.2022, author = {Schulte-Tigges, Joschua and F{\"o}rster, Marco and Nikolovski, Gjorgji and Reke, Michael and Ferrein, Alexander and Kaszner, Daniel and Matheis, Dominik and Walter, Thomas}, title = {Benchmarking of various LiDAR sensors for use in self-driving vehicles in real-world environments}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {19}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s22197146}, pages = {20 Seiten}, year = {2022}, abstract = {Abstract In this paper, we report on our benchmark results of the LiDAR sensors Livox Horizon, Robosense M1, Blickfeld Cube, Blickfeld Cube Range, Velodyne Velarray H800, and Innoviz Pro. The idea was to test the sensors in different typical scenarios that were defined with real-world use cases in mind, in order to find a sensor that meet the requirements of self-driving vehicles. For this, we defined static and dynamic benchmark scenarios. In the static scenarios, both LiDAR and the detection target do not move during the measurement. In dynamic scenarios, the LiDAR sensor was mounted on the vehicle which was driving toward the detection target. We tested all mentioned LiDAR sensors in both scenarios, show the results regarding the detection accuracy of the targets, and discuss their usefulness for deployment in self-driving cars.}, language = {en} } @article{HaegerGrankinWagner2023, author = {Haeger, Gerrit and Grankin, Alina and Wagner, Michaela}, title = {Construction of an Aspergillus oryzae triple amylase deletion mutant as a chassis to evaluate industrially relevant amylases using multiplex CRISPR/Cas9 editing technology}, series = {Applied Research}, journal = {Applied Research}, number = {Early View}, publisher = {Wiley-VCH}, issn = {2702-4288}, doi = {10.1002/appl.202200106}, pages = {1 -- 15}, year = {2023}, abstract = {Aspergillus oryzae is an industrially relevant organism for the secretory production of heterologous enzymes, especially amylases. The activities of potential heterologous amylases, however, cannot be quantified directly from the supernatant due to the high background activity of native α-amylase. This activity is caused by the gene products of amyA, amyB, and amyC. In this study, an in vitro CRISPR/Cas9 system was established in A. oryzae to delete these genes simultaneously. First, pyrG of A. oryzae NSAR1 was mutated by exploiting NHEJ to generate a counter-selection marker. Next, all amylase genes were deleted simultaneously by co-transforming a repair template carrying pyrG of Aspergillus nidulans and flanking sequences of amylase gene loci. The rate of obtained triple knock-outs was 47\%. We showed that triple knockouts do not retain any amylase activity in the supernatant. The established in vitro CRISPR/Cas9 system was used to achieve sequence-specific knock-in of target genes. The system was intended to incorporate a single copy of the gene of interest into the desired host for the development of screening methods. Therefore, an integration cassette for the heterologous Fpi amylase was designed to specifically target the amyB locus. The site-specific integration rate of the plasmid was 78\%, with exceptional additional integrations. Integration frequency was assessed via qPCR and directly correlated with heterologous amylase activity. Hence, we could compare the efficiency between two different signal peptides. In summary, we present a strategy to exploit CRISPR/Cas9 for gene mutation, multiplex knock-out, and the targeted knock-in of an expression cassette in A. oryzae. Our system provides straightforward strain engineering and paves the way for development of fungal screening systems.}, language = {en} } @article{RuebbelkeVoegeleGrajewskietal.2023, author = {R{\"u}bbelke, Dirk and V{\"o}gele, Stefan and Grajewski, Matthias and Zobel, Luzy}, title = {Cross border adjustment mechanism: Initial data for the assessment of hydrogen-based steel production}, series = {Data in Brief}, volume = {47}, journal = {Data in Brief}, number = {Article 108907}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-3409}, doi = {10.1016/j.dib.2023.108907}, pages = {1 -- 5}, year = {2023}, abstract = {Ambitious climate targets affect the competitiveness of industries in the international market. To prevent such industries from moving to other countries in the wake of increased climate protection efforts, cost adjustments may become necessary. Their design requires knowledge of country-specific production costs. Here, we present country-specific cost figures for different production routes of steel, paying particular attention to transportation costs. The data can be used in floor price models aiming to assess the competitiveness of different steel production routes in different countries (R{\"u}bbelke, 2022).}, 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} } @article{NiedermeierPennerUsherovichetal.2023, author = {Niedermeier, Jana and Penner, Crystal and Usherovich, Samuel and B{\´e}langer-Champagne, Camille and Paulßen, Elisabeth and Cornelia, Hoehr}, 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{ŠakićMarinkovićButenwegetal.2023, author = {Šakić, Bogdan and Marinković, Marko and Butenweg, Christoph and Klinkel, Sven}, title = {Influence of slab deflection on the out-of-plane capacity of unreinforced masonry partition walls}, series = {Engineering Structures}, volume = {276}, journal = {Engineering Structures}, editor = {Yang, J.}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0141-0296}, doi = {10.1016/j.engstruct.2022.115342}, year = {2023}, abstract = {Severe damage of non-structural elements is noticed in previous earthquakes, causing high economic losses and posing a life threat for the people. Masonry partition walls are one of the most commonly used non-structural elements. Therefore, their behaviour under earthquake loading in out-of-plane (OOP) direction is investigated by several researches in the past years. However, none of the existing experimental campaigns or analytical approaches consider the influence of prior slab deflection on OOP response of partition walls. Moreover, none of the existing construction techniques for the connection of partition walls with surrounding reinforced concrete (RC) is investigated for the combined slab deflection and OOP loading. However, the inevitable time-dependent behaviour of RC slabs leads to high values of final slab deflections which can further influence boundary conditions of partition walls. Therefore, a comprehensive study on the influence of slab deflection on the OOP capacity of masonry partitions is conducted. In the first step, experimental tests are carried out. Results of experimental tests are further used for the calibration of the numerical model employed for a parametric study. Based on the results, behaviour under combined loading for different construction techniques is explained. The results show that slab deflection leads either to severe damage or to a high reduction of OOP capacity. Existing practical solutions do not account for these effects. In this contribution, recommendations to overcome the problems of combined slab deflection and OOP loading on masonry partition walls are given. Possible interaction of in-plane (IP) loading, with the combined slab deflection and OOP loading on partition walls, is not investigated in this study.}, language = {en} } @article{KubalskiButenwegElDeib2022, author = {Kubalski, Thomas and Butenweg, Christoph and El-Deib, Khaled}, title = {Vereinfachte Ber{\"u}cksichtigung der Rahmentragwirkung in Mauerwerksgeb{\"a}uden}, series = {Bautechnik}, volume = {99}, journal = {Bautechnik}, number = {12}, editor = {Jesse, Dirk}, publisher = {Ernst \& Sohn}, address = {Berlin}, issn = {0932-8351}, doi = {10.1002/bate.202200081}, pages = {865 -- 928}, year = {2022}, abstract = {Aufgrund der gestiegenen Anforderungen durch h{\"o}here Ein-wirkungen aus Wind und Erdbeben ist eine Verbesserung und Optimierung der Berechnungs- und Bemessungsans{\"a}tze f{\"u}r Mauerwerksbauten erforderlich. Eine bessere Ausnutzung der Tragwerksreserven ist durch die Ber{\"u}cksichtigung der Rah-mentragwirkung mit einer Aktivierung der Deckenscheiben in den Rechenmodellen m{\"o}glich, die in der Praxis aufgrund der Komplexit{\"a}t der Wand-Decken-Interaktion bislang nicht aus-genutzt wird. Im vorliegenden Aufsatz wird ein vereinfachter Ansatz auf Grundlage der mitwirkenden Plattenbreite von Schubw{\"a}nden aus Mauerwerk vorgestellt, der die wesentli-chen Einfl ussfaktoren in parametrisierten Tabellen erfasst. Damit steht den Tragwerksplanern ein einfach anwendbares Werkzeug zur Verf{\"u}gung, um die Rahmentragwirkung in der Mauerwerksbemessung anzusetzen.}, language = {de} } @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{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{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} } @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{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{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{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{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{BaringhausGaigall2017, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {On Hotelling's T² test in a special paired sample case}, series = {Communications in Statistics - Theory and Methods}, volume = {48}, journal = {Communications in Statistics - Theory and Methods}, number = {2}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-415X}, doi = {10.1080/03610926.2017.1408828}, pages = {257 -- 267}, year = {2017}, abstract = {In a special paired sample case, Hotelling's T² test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.}, language = {en} } @article{BaringhausGaigall2017, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {Hotelling's T² tests in paired and independent survey samples: An efficiency comparison}, series = {Journal of Multivariate Analysis}, volume = {2017}, journal = {Journal of Multivariate Analysis}, number = {154}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0047-259X}, doi = {10.1016/j.jmva.2016.11.004}, pages = {177 -- 198}, year = {2017}, abstract = {Hotelling's T² tests in paired and independent survey samples are compared using the traditional asymptotic efficiency concepts of Hodges-Lehmann, Bahadur and Pitman, as well as through criteria based on the volumes of corresponding confidence regions. Conditions characterizing the superiority of a procedure are given in terms of population canonical correlation type coefficients. Statistical tests for checking these conditions are developed. Test statistics based on the eigenvalues of a symmetrized sample cross-covariance matrix are suggested, as well as test statistics based on sample canonical correlation type coefficients.}, language = {en} } @article{BaringhausGaigall2018, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {Efficiency comparison of the Wilcoxon tests in paired and independent survey samples}, series = {Metrika}, volume = {2018}, journal = {Metrika}, number = {81}, publisher = {Springer}, address = {Berlin}, issn = {1435-926X}, doi = {10.1007/s00184-018-0661-4}, pages = {891 -- 930}, year = {2018}, abstract = {The efficiency concepts of Bahadur and Pitman are used to compare the Wilcoxon tests in paired and independent survey samples. A comparison through the length of corresponding confidence intervals is also done. Simple conditions characterizing the dominance of a procedure are derived. Statistical tests for checking these conditions are suggested and discussed.}, language = {de} } @article{BaringhausGaigall2019, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {On an asymptotic relative efficiency concept based on expected volumes of confidence regions}, series = {Statistics - A Journal of Theoretical and Applied Statistic}, volume = {53}, journal = {Statistics - A Journal of Theoretical and Applied Statistic}, number = {6}, publisher = {Taylor \& Francis}, address = {London}, issn = {1029-4910}, doi = {10.1080/02331888.2019.1683560}, pages = {1396 -- 1436}, year = {2019}, abstract = {The paper deals with an asymptotic relative efficiency concept for confidence regions of multidimensional parameters that is based on the expected volumes of the confidence regions. Under standard conditions the asymptotic relative efficiencies of confidence regions are seen to be certain powers of the ratio of the limits of the expected volumes. These limits are explicitly derived for confidence regions associated with certain plugin estimators, likelihood ratio tests and Wald tests. Under regularity conditions, the asymptotic relative efficiency of each of these procedures with respect to each one of its competitors is equal to 1. The results are applied to multivariate normal distributions and multinomial distributions in a fairly general setting.}, language = {en} } @article{Gaigall2019, author = {Gaigall, Daniel}, title = {On a new approach to the multi-sample goodness-of-fit problem}, series = {Communications in Statistics - Simulation and Computation}, volume = {53}, journal = {Communications in Statistics - Simulation and Computation}, number = {10}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-4141}, doi = {10.1080/03610918.2019.1618472}, pages = {2971 -- 2989}, year = {2019}, abstract = {Suppose we have k samples X₁,₁,…,X₁,ₙ₁,…,Xₖ,₁,…,Xₖ,ₙₖ with different sample sizes ₙ₁,…,ₙₖ and unknown underlying distribution functions F₁,…,Fₖ as observations plus k families of distribution functions {G₁(⋅,ϑ);ϑ∈Θ},…,{Gₖ(⋅,ϑ);ϑ∈Θ}, each indexed by elements ϑ from the same parameter set Θ, we consider the new goodness-of-fit problem whether or not (F₁,…,Fₖ) belongs to the parametric family {(G₁(⋅,ϑ),…,Gₖ(⋅,ϑ));ϑ∈Θ}. New test statistics are presented and a parametric bootstrap procedure for the approximation of the unknown null distributions is discussed. Under regularity assumptions, it is proved that the approximation works asymptotically, and the limiting distributions of the test statistics in the null hypothesis case are determined. Simulation studies investigate the quality of the new approach for small and moderate sample sizes. Applications to real-data sets illustrate how the idea can be used for verifying model assumptions.}, language = {en} } @article{DitzhausGaigall2018, author = {Ditzhaus, Marc and Gaigall, Daniel}, title = {A consistent goodness-of-fit test for huge dimensional and functional data}, series = {Journal of Nonparametric Statistics}, volume = {30}, journal = {Journal of Nonparametric Statistics}, number = {4}, publisher = {Taylor \& Francis}, address = {Abingdon}, issn = {1029-0311}, doi = {10.1080/10485252.2018.1486402}, pages = {834 -- 859}, year = {2018}, abstract = {A nonparametric goodness-of-fit test for random variables with values in a separable Hilbert space is investigated. To verify the null hypothesis that the data come from a specific distribution, an integral type test based on a Cram{\´e}r-von-Mises statistic is suggested. The convergence in distribution of the test statistic under the null hypothesis is proved and the test's consistency is concluded. Moreover, properties under local alternatives are discussed. Applications are given for data of huge but finite dimension and for functional data in infinite dimensional spaces. A general approach enables the treatment of incomplete data. In simulation studies the test competes with alternative proposals.}, language = {en} } @article{BaringhausGaigallThiele2018, author = {Baringhaus, Ludwig and Gaigall, Daniel and Thiele, Jan Philipp}, title = {Statistical inference for L²-distances to uniformity}, series = {Computational Statistics}, volume = {2018}, journal = {Computational Statistics}, number = {33}, publisher = {Springer}, address = {Berlin}, issn = {1613-9658}, doi = {10.1007/s00180-018-0820-0}, pages = {1863 -- 1896}, year = {2018}, abstract = {The paper deals with the asymptotic behaviour of estimators, statistical tests and confidence intervals for L²-distances to uniformity based on the empirical distribution function, the integrated empirical distribution function and the integrated empirical survival function. Approximations of power functions, confidence intervals for the L²-distances and statistical neighbourhood-of-uniformity validation tests are obtained as main applications. The finite sample behaviour of the procedures is illustrated by a simulation study.}, language = {en} } @article{BaringhausGaigall2015, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {On an independence test approach to the goodness-of-fit problem}, series = {Journal of Multivariate Analysis}, volume = {2015}, journal = {Journal of Multivariate Analysis}, number = {140}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0047-259X}, doi = {10.1016/j.jmva.2015.05.013}, pages = {193 -- 208}, year = {2015}, abstract = {Let X₁,…,Xₙ be independent and identically distributed random variables with distribution F. Assuming that there are measurable functions f:R²→R and g:R²→R characterizing a family F of distributions on the Borel sets of R in the way that the random variables f(X₁,X₂),g(X₁,X₂) are independent, if and only if F∈F, we propose to treat the testing problem H:F∈F,K:F∉F by applying a consistent nonparametric independence test to the bivariate sample variables (f(Xᵢ,Xⱼ),g(Xᵢ,Xⱼ)),1⩽i,j⩽n,i≠j. A parametric bootstrap procedure needed to get critical values is shown to work. The consistency of the test is discussed. The power performance of the procedure is compared with that of the classical tests of Kolmogorov-Smirnov and Cram{\´e}r-von Mises in the special cases where F is the family of gamma distributions or the family of inverse Gaussian distributions.}, language = {en} } @article{Gaigall2021, author = {Gaigall, Daniel}, title = {Test for Changes in the Modeled Solvency Capital Requirement of an Internal Risk Model}, series = {ASTIN Bulletin}, volume = {51}, journal = {ASTIN Bulletin}, number = {3}, publisher = {Cambridge Univ. Press}, address = {Cambridge}, issn = {1783-1350}, doi = {10.1017/asb.2021.20}, pages = {813 -- 837}, year = {2021}, abstract = {In the context of the Solvency II directive, the operation of an internal risk model is a possible way for risk assessment and for the determination of the solvency capital requirement of an insurance company in the European Union. A Monte Carlo procedure is customary to generate a model output. To be compliant with the directive, validation of the internal risk model is conducted on the basis of the model output. For this purpose, we suggest a new test for checking whether there is a significant change in the modeled solvency capital requirement. Asymptotic properties of the test statistic are investigated and a bootstrap approximation is justified. A simulation study investigates the performance of the test in the finite sample case and confirms the theoretical results. The internal risk model and the application of the test is illustrated in a simplified example. The method has more general usage for inference of a broad class of law-invariant and coherent risk measures on the basis of a paired sample.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic on partly not identically distributed data}, series = {Communications in Statistics - Theory and Methods}, volume = {51}, journal = {Communications in Statistics - Theory and Methods}, number = {12}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-415X}, doi = {10.1080/03610926.2020.1805767}, pages = {4006 -- 4028}, year = {2020}, abstract = {The established Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic is investigated for partly not identically distributed data. Surprisingly, it turns out that the statistic has the well-known distribution-free limiting null distribution of the classical criterion under standard regularity conditions. An application is testing goodness-of-fit for the regression function in a non parametric random effects meta-regression model, where the consistency is obtained as well. Simulations investigate size and power of the approach for small and moderate sample sizes. A real data example based on clinical trials illustrates how the test can be used in applications.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Testing marginal homogeneity of a continuous bivariate distribution with possibly incomplete paired data}, series = {Metrika}, volume = {2020}, journal = {Metrika}, number = {83}, publisher = {Springer}, issn = {1435-926X}, doi = {10.1007/s00184-019-00742-5}, pages = {437 -- 465}, year = {2020}, abstract = {We discuss the testing problem of homogeneity of the marginal distributions of a continuous bivariate distribution based on a paired sample with possibly missing components (missing completely at random). Applying the well-known two-sample Cr{\´a}mer-von-Mises distance to the remaining data, we determine the limiting null distribution of our test statistic in this situation. It is seen that a new resampling approach is appropriate for the approximation of the unknown null distribution. We prove that the resulting test asymptotically reaches the significance level and is consistent. Properties of the test under local alternatives are pointed out as well. Simulations investigate the quality of the approximation and the power of the new approach in the finite sample case. As an illustration we apply the test to real data sets.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Rothman-Woodroofe symmetry test statistic revisited}, series = {Computational Statistics \& Data Analysis}, volume = {2020}, journal = {Computational Statistics \& Data Analysis}, number = {142}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0167-9473}, doi = {10.1016/j.csda.2019.106837}, pages = {Artikel 106837}, year = {2020}, abstract = {The Rothman-Woodroofe symmetry test statistic is revisited on the basis of independent but not necessarily identically distributed random variables. The distribution-freeness if the underlying distributions are all symmetric and continuous is obtained. The results are applied for testing symmetry in a meta-analysis random effects model. The consistency of the procedure is discussed in this situation as well. A comparison with an alternative proposal from the literature is conducted via simulations. Real data are analyzed to demonstrate how the new approach works in practice.}, language = {en} } @article{DitzhausGaigall2022, author = {Ditzhaus, Marc and Gaigall, Daniel}, title = {Testing marginal homogeneity in Hilbert spaces with applications to stock market returns}, series = {Test}, volume = {2022}, journal = {Test}, number = {31}, publisher = {Springer}, issn = {1863-8260}, doi = {10.1007/s11749-022-00802-5}, pages = {749 -- 770}, year = {2022}, abstract = {This paper considers a paired data framework and discusses the question of marginal homogeneity of bivariate high-dimensional or functional data. The related testing problem can be endowed into a more general setting for paired random variables taking values in a general Hilbert space. To address this problem, a Cram{\´e}r-von-Mises type test statistic is applied and a bootstrap procedure is suggested to obtain critical values and finally a consistent test. The desired properties of a bootstrap test can be derived that are asymptotic exactness under the null hypothesis and consistency under alternatives. Simulations show the quality of the test in the finite sample case. A possible application is the comparison of two possibly dependent stock market returns based on functional data. The approach is demonstrated based on historical data for different stock market indices.}, language = {en} } @article{GaigallGerstenbergTrinh2022, author = {Gaigall, Daniel and Gerstenberg, Julian and Trinh, Thi Thu Ha}, title = {Empirical process of concomitants for partly categorial data and applications in statistics}, series = {Bernoulli}, volume = {28}, journal = {Bernoulli}, number = {2}, publisher = {International Statistical Institute}, address = {Den Haag, NL}, issn = {1573-9759}, doi = {10.3150/21-BEJ1367}, pages = {803 -- 829}, year = {2022}, abstract = {On the basis of independent and identically distributed bivariate random vectors, where the components are categorial and continuous variables, respectively, the related concomitants, also called induced order statistic, are considered. The main theoretical result is a functional central limit theorem for the empirical process of the concomitants in a triangular array setting. A natural application is hypothesis testing. An independence test and a two-sample test are investigated in detail. The fairly general setting enables limit results under local alternatives and bootstrap samples. For the comparison with existing tests from the literature simulation studies are conducted. The empirical results obtained confirm the theoretical findings.}, 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} } @article{BaringhausGaigall2022, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {A goodness-of-fit test for the compound Poisson exponential model}, series = {Journal of Multivariate Analysis}, volume = {195}, journal = {Journal of Multivariate Analysis}, number = {Article 105154}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0047-259X}, doi = {10.1016/j.jmva.2022.105154}, year = {2022}, abstract = {On the basis of bivariate data, assumed to be observations of independent copies of a random vector (S,N), we consider testing the hypothesis that the distribution of (S,N) belongs to the parametric class of distributions that arise with the compound Poisson exponential model. Typically, this model is used in stochastic hydrology, with N as the number of raindays, and S as total rainfall amount during a certain time period, or in actuarial science, with N as the number of losses, and S as total loss expenditure during a certain time period. The compound Poisson exponential model is characterized in the way that a specific transform associated with the distribution of (S,N) satisfies a certain differential equation. Mimicking the function part of this equation by substituting the empirical counterparts of the transform we obtain an expression the weighted integral of the square of which is used as test statistic. We deal with two variants of the latter, one of which being invariant under scale transformations of the S-part by fixed positive constants. Critical values are obtained by using a parametric bootstrap procedure. The asymptotic behavior of the tests is discussed. A simulation study demonstrates the performance of the tests in the finite sample case. The procedure is applied to rainfall data and to an actuarial dataset. A multivariate extension is also discussed.}, language = {en} } @article{TranTrinhDaoetal.2022, author = {Tran, Ngoc Trinh and Trinh, Tu Luc and Dao, Ngoc Tien and Giap, Van Tan and Truong, Manh Khuyen and Dinh, Thuy Ha and Staat, Manfred}, title = {FEM shakedown analysis of structures under random strength with chance constrained programming}, series = {Vietnam Journal of Mechanics}, volume = {44}, journal = {Vietnam Journal of Mechanics}, number = {4}, publisher = {Vietnam Academy of Science and Technology (VAST)}, issn = {0866-7136}, doi = {10.15625/0866-7136/17943}, pages = {459 -- 473}, year = {2022}, abstract = {Direct methods, comprising limit and shakedown analysis, are a branch of computational mechanics. They play a significant role in mechanical and civil engineering design. The concept of direct methods aims to determine the ultimate load carrying capacity of structures beyond the elastic range. In practical problems, the direct methods lead to nonlinear convex optimization problems with a large number of variables and constraints. If strength and loading are random quantities, the shakedown analysis can be formulated as stochastic programming problem. In this paper, a method called chance constrained programming is presented, which is an effective method of stochastic programming to solve shakedown analysis problems under random conditions of strength. In this study, the loading is deterministic, and the strength is a normally or lognormally distributed variable.}, language = {en} } @article{Czarnecki2015, author = {Czarnecki, Christian}, title = {Moderne Telekommunikationsprodukte erfordern standardisierte Gesch{\"a}ftsprozesse}, series = {Wirtschaft und Wissenschaft}, journal = {Wirtschaft und Wissenschaft}, number = {2}, publisher = {Deutsche Telekom AG. Fachhochschule Leipzig}, address = {Leipzig}, pages = {7 -- 7}, year = {2015}, language = {de} } @article{MuellerSeginWeigandetal.2022, author = {Mueller, Tobias and Segin, Alexander and Weigand, Christoph and Schmitt, Robert H.}, title = {Feature selection for measurement models}, series = {International journal of quality \& reliability management}, journal = {International journal of quality \& reliability management}, number = {Vol. ahead-of-print, No. ahead-of-print.}, publisher = {Emerald Group Publishing Limited}, address = {Bingley}, issn = {0265-671X}, doi = {10.1108/IJQRM-07-2021-0245}, year = {2022}, abstract = {Purpose In the determination of the measurement uncertainty, the GUM procedure requires the building of a measurement model that establishes a functional relationship between the measurand and all influencing quantities. Since the effort of modelling as well as quantifying the measurement uncertainties depend on the number of influencing quantities considered, the aim of this study is to determine relevant influencing quantities and to remove irrelevant ones from the dataset. Design/methodology/approach In this work, it was investigated whether the effort of modelling for the determination of measurement uncertainty can be reduced by the use of feature selection (FS) methods. For this purpose, 9 different FS methods were tested on 16 artificial test datasets, whose properties (number of data points, number of features, complexity, features with low influence and redundant features) were varied via a design of experiments. Findings Based on a success metric, the stability, universality and complexity of the method, two FS methods could be identified that reliably identify relevant and irrelevant influencing quantities for a measurement model. Originality/value For the first time, FS methods were applied to datasets with properties of classical measurement processes. The simulation-based results serve as a basis for further research in the field of FS for measurement models. The identified algorithms will be applied to real measurement processes in the future.}, language = {en} } @article{RuebbelkeVoegeleGrajewskietal.2022, author = {R{\"u}bbelke, Dirk and V{\"o}gele, Stefan and Grajewski, Matthias and Zobel, Luzy}, title = {Hydrogen-based steel production and global climate protection: An empirical analysis of the potential role of a European cross border adjustment mechanism}, series = {Journal of Cleaner Production}, volume = {380}, journal = {Journal of Cleaner Production}, number = {Part 2, Art. Nr.:135040}, publisher = {Elsevier}, issn = {0959-6526}, doi = {10.1016/j.jclepro.2022.135040}, year = {2022}, abstract = {The European Union's aim to become climate neutral by 2050 necessitates ambitious efforts to reduce carbon emissions. Large reductions can be attained particularly in energy intensive sectors like iron and steel. In order to prevent the relocation of such industries outside the EU in the course of tightening environmental regulations, the establishment of a climate club jointly with other large emitters and alternatively the unilateral implementation of an international cross-border carbon tax mechanism are proposed. This article focuses on the latter option choosing the steel sector as an example. In particular, we investigate the financial conditions under which a European cross border mechanism is capable to protect hydrogen-based steel production routes employed in Europe against more polluting competition from abroad. By using a floor price model, we assess the competitiveness of different steel production routes in selected countries. We evaluate the climate friendliness of steel production on the basis of specific GHG emissions. In addition, we utilize an input-output price model. It enables us to assess impacts of rising cost of steel production on commodities using steel as intermediates. Our results raise concerns that a cross-border tax mechanism will not suffice to bring about competitiveness of hydrogen-based steel production in Europe because the cost tends to remain higher than the cost of steel production in e.g. China. Steel is a classic example for a good used mainly as intermediate for other products. Therefore, a cross-border tax mechanism for steel will increase the price of products produced in the EU that require steel as an input. This can in turn adversely affect competitiveness of these sectors. Hence, the effects of higher steel costs on European exports should be borne in mind and could require the cross-border adjustment mechanism to also subsidize exports.}, language = {en} } @article{CzarneckiHeuserKraemeretal.2006, author = {Czarnecki, Christian and Heuser, Marcus and Kr{\"a}mer, Christian and Stummer, Christoph and Theisinger, Felix and Wettklo, Michael}, title = {How to get more customer satisfaction : Erfolg im Wettbewerb durch kundenzentrierte Prozesse}, series = {Detecon Management Report}, journal = {Detecon Management Report}, number = {3}, publisher = {Detecon Internat. GmbH}, address = {Eschborn}, issn = {1867-3147}, pages = {29 -- 33}, year = {2006}, abstract = {Unternehmen sind in der Regel {\"u}berzeugt, dass sie die Bed{\"u}rfnisse ihrer Kunden in den Mittelpunkt stellen. Aber in der direkten Interaktion mit dem Kunden zeigen sie h{\"a}ufig Schw{\"a}chen. Der folgende Beitrag illustriert, wie durch eine konsequente Ausrichtung der Wertsch{\"o}pfungsprozesse auf die zentralen Kundenbed{\"u}rfnisse ein Dreifacheffekt erzielt werden kann: Nachhaltig erh{\"o}hte Kundenzufriedenheit, gesteigerte Effizienz und eine Differenzierung im Wettbewerb.}, language = {de} } @article{CzarneckiGeierPflug2017, author = {Czarnecki, Christian and Geier, Jari and Pflug, Karolin}, title = {Netzvirtualisierung durch SDN und NFV : Unternehmensprozesse auf dem Pr{\"u}fstand}, series = {LANline}, journal = {LANline}, publisher = {AWI Aktuelles Wissen Verl.-Ges.}, address = {Trostberg}, issn = {0942-4172}, year = {2017}, abstract = {Kundenanforderungen an Netzwerke haben sich in den vergangenen Jahren stark ver{\"a}ndert. Mit NFV und SDN sind Unternehmen technisch in der Lage, diesen gerecht zu werden. Die Provider stehen jedoch vor großen Herausforderungen: Insbesondere Produkte und Prozesse m{\"u}ssen angepasst und agiler werden, um die St{\"a}rken von NFV und SDN zum Kundenvorteil auszuspielen.}, language = {de} } @article{BensbergAuthCzarnecki2020, author = {Bensberg, Frank and Auth, Gunnar and Czarnecki, Christian}, title = {Literaturanalyse mit Text Mining}, series = {E-Learning and Education (eleed)}, journal = {E-Learning and Education (eleed)}, number = {13}, editor = {Haake, J{\"o}rg M.}, publisher = {FernUniversit{\"a}t in Hagen}, address = {Hagen}, issn = {1860-7470}, pages = {1 -- 13}, year = {2020}, abstract = {Die Durchf{\"u}hrung einer systematischen Literaturrecherche ist eine zentrale Kompetenz wissenschaftlichen Arbeitens und bildet daher einen festen Ausbildungsbestandteil von Bachelor- und Masterstudieng{\"a}ngen. In entsprechenden Lehrveranstaltungen werden Studierende zwar mit den grundlegenden Hilfsmitteln zur Suche und Verwaltung von Literatur vertraut gemacht, allerdings werden die Potenziale textanalytischer Methoden und Anwendungssysteme (Text Mining, Text Analytics) dabei zumeist nicht abgedeckt. Folglich werden Datenkompetenzen, die zur systemgest{\"u}tzten Analyse und Erschließung von Literaturdaten erforderlich sind, nicht hinreichend ausgepr{\"a}gt. Um diese Kompetenzl{\"u}cke zu adressieren, ist an der Hochschule Osnabr{\"u}ck eine Lehrveranstaltung konzipiert und projektorientiert umgesetzt worden, die sich insbesondere an Studierende wirtschaftswissenschaftlicher Studieng{\"a}nge richtet. Dieser Beitrag dokumentiert die fachliche sowie technische Ausgestaltung dieser Veranstaltung und zeigt Potenziale f{\"u}r die k{\"u}nftige Weiterentwicklung auf.}, language = {de} } @article{HoerenbaumLaumannProkop2016, author = {H{\"o}renbaum, Christoph and Laumann, J{\"o}rg and Prokop, Ines}, title = {Zur Anwendung des Eurocode 3 Teil 1-2 f{\"u}r die Heißbemessung und Anregungen f{\"u}r dessen Novellierung}, series = {Stahlbau}, volume = {85}, journal = {Stahlbau}, number = {6}, publisher = {Ernst \& Sohn GmbH}, address = {Berlin}, issn = {1437-1049}, doi = {10.1002/stab.201610382}, pages = {429 -- 434}, year = {2016}, abstract = {Die Eurocodes werden bis zum Jahr 2020 im Europ{\"a}ischen Komitee f{\"u}r Normung (CEN), Technisches Komitee TC 250, {\"u}berarbeitet. In Vorbereitung auf die Eurocode-Novellierung haben engagierte Ingenieure im Rahmen der Initiative PraxisRegeln Bau (PRB) die f{\"u}r die praktische Anwendung h{\"a}ufig genutzten Teile des Eurocode 3 untersucht. Mit dem Ziel, die Praxistauglichkeit des Eurocode 3 f{\"u}r die Heißbemessung zu verbessern, wurden die bestehende Norm EN 1993 Teil 1-2 insbesondere in Bezug auf die Anwenderfreundlichkeit analysiert und Vorschl{\"a}ge f{\"u}r die europ{\"a}ische Novellierung erarbeitet. Die Analysen zeigen, dass durch Umstrukturierungen und durch die Einf{\"u}hrung von Tabellen die Verst{\"a}ndlichkeit und Anwenderfreundlichkeit der Regeln f{\"u}r die Heißbemessung bedeutend erh{\"o}ht werden k{\"o}nnen.}, language = {de} } @article{KindmannKrausLaumannetal.2022, author = {Kindmann, Rolf and Kraus, Matthias and Laumann, J{\"o}rg and Vette, Jan}, title = {Verallgemeinerte Berechnungsmethode f{\"u}r in Beton eingespannte Stahlprofile - Einspanntiefen, Tragf{\"a}higkeitsnachweise und Bemessungshilfen}, series = {Stahlbau}, volume = {93}, journal = {Stahlbau}, number = {Early View}, publisher = {Ernst \& Sohn GmbH}, address = {Berlin}, issn = {1437-1049}, doi = {10.1002/stab.202200024}, pages = {1 -- 25}, year = {2022}, abstract = {St{\"u}tzen und Tr{\"a}ger aus Stahlprofilen k{\"o}nnen in Fundamente oder W{\"a}nde aus Stahlbeton einbetoniert werden. Diese Anschl{\"u}sse wirken in der Regel wie Einspannungen, die eine ausreichende Einspanntiefe erfordern. Im Folgenden wird eine verallgemeinerte Berechnungsmethode f{\"u}r in Stahlbetonkonstruktionen eingespannte Stahlprofile aus gewalzten I-Profilen, geschweißten I-Profilen, runden Hohlprofilen, eckigen Hohlprofilen und einzelligen Kastenquerschnitten vorgestellt. F{\"u}r Beanspruchungen infolge einachsiger Biegung um die starke und schwache Profilachse werden der profilabh{\"a}ngige Ansatz der Betondruckspannungen im Einspannbereich und die Ermittlung der Einspanntiefe behandelt. Unter Ber{\"u}cksichtigung der Normalkraft werden an den maßgebenden Stellen Tragf{\"a}higkeitsnachweise f{\"u}r die Stahlprofile gef{\"u}hrt. Als Erg{\"a}nzung zu den Berechnungsformeln werden Bemessungshilfen zur Verf{\"u}gung gestellt, die die Wahl der mitwirkenden Breiten und der Einspanntiefen erleichtert.}, language = {de} } @article{EmigHebelSchwark2022, author = {Emig, J. and Hebel, Christoph and Schwark, A.}, title = {Einsatzbereiche f{\"u}r Verkehrsnachfragemodelle}, series = {Straßenverkehrstechnik}, volume = {66}, journal = {Straßenverkehrstechnik}, number = {10}, publisher = {Kirschbaum Verlag GmbH}, address = {Bonn}, issn = {0039-2219}, doi = {10.53184/SVT10-2022-2}, pages = {727 -- 736}, year = {2022}, abstract = {In der Praxis bestehen vielf{\"a}ltige Einsatzbereiche f{\"u}r Verkehrsnachfragemodelle. Mit ihnen k{\"o}nnen Kenngr{\"o}ßen des Verkehrsangebots und der Verkehrsnachfrage f{\"u}r den heutigen Zustand wie auch f{\"u}r zuk{\"u}nftige Zust{\"a}nde bereitgestellt werden, um so die Grundlagen f{\"u}r verkehrsplanerische Entscheidungen zu liefern. Die neuen „Empfehlungen zum Einsatz von Verkehrsnachfragemodellen f{\"u}r den Personenverkehr" (EVNM-PV) (FGSV 2022) veranschaulichen anhand von typischen Planungsaufgaben, welche differenzierten Anforderungen daraus f{\"u}r die Modellkonzeption und -erstellung resultieren. Vor dem Hintergrund der konkreten Aufgabenstellung sowie deren spezifischer planerischer Anforderungen bildet die abzuleitende Modellspezifikation die verabredete Grundlage zwischen Auftraggeber und Modellersteller f{\"u}r die konkrete inhaltliche, fachliche Ausgestaltung des Verkehrsmodells.}, language = {de} } @article{HahnHebelManz2022, author = {Hahn, Geogr W. and Hebel, Christoph and Manz, W.}, title = {Die neuen Empfehlungen f{\"u}r Verkehrsnachfragemodellierung im Personenverkehr}, series = {Straßenverkehrstechnik}, volume = {66}, journal = {Straßenverkehrstechnik}, number = {10}, publisher = {Kirschbaum Verlag GmbH}, address = {Bonn}, issn = {0039-2219}, doi = {10.53184/SVT10-2022-1}, pages = {721 -- 726}, year = {2022}, abstract = {Die neu erschienenen „Empfehlungen zum Einsatz von Verkehrsnachfragemodellen f{\"u}r den Personenverkehr" liefern erstmals als Empfehlungspapier der Forschungsgesellschaft f{\"u}r Straßen- und Verkehrswesen einen umfassenden {\"U}berblick zu den verschiedenen Aspekten der Modellierung und geben dem Fachplaner konkrete Hilfestellung f{\"u}r die Konzeption von Nachfragemodellen. Das Empfehlungspapier zielt unter anderem darauf ab, die Erwartungen und das Anspruchsniveau in Hinblick auf Sachgerechtigkeit der Modelle, die erzielbare Modellqualit{\"a}t und den Detaillierungsgrad der Modellaussagen zu harmonisieren.}, language = {de} } @article{CzarneckiWinkelmannSpiliopoulou2010, author = {Czarnecki, Christian and Winkelmann, Axel and Spiliopoulou, Myra}, title = {Services in electronic telecommunication markets: a framework for planning the virtualization of processes}, series = {Electronic Markets}, volume = {20}, journal = {Electronic Markets}, number = {3-4}, publisher = {Springer}, address = {Berlin}, issn = {1422-8890}, doi = {10.1007/s12525-010-0045-8}, pages = {197 -- 207}, year = {2010}, abstract = {The potential of electronic markets in enabling innovative product bundles through flexible and sustainable partnerships is not yet fully exploited in the telecommunication industry. One reason is that bundling requires seamless de-assembling and re-assembling of business processes, whilst processes in telecommunication companies are often product-dependent and hard to virtualize. We propose a framework for the planning of the virtualization of processes, intended to assist the decision maker in prioritizing the processes to be virtualized: (a) we transfer the virtualization pre-requisites stated by the Process Virtualization Theory in the context of customer-oriented processes in the telecommunication industry and assess their importance in this context, (b) we derive IT-oriented requirements for the removal of virtualization barriers and highlight their demand on changes at different levels of the organization. We present a first evaluation of our approach in a case study and report on lessons learned and further steps to be performed.}, language = {en} } @article{CzarneckiSpiliopoulou2012, author = {Czarnecki, Christian and Spiliopoulou, Myra}, title = {A holistic framework for the implementation of a next generation network}, series = {International Journal of Business Information Systems}, volume = {9}, journal = {International Journal of Business Information Systems}, number = {4}, publisher = {Inderscience Enterprises}, address = {Olney, Bucks}, issn = {1746-0972}, doi = {10.1504/IJBIS.2012.046291}, pages = {385 -- 401}, year = {2012}, abstract = {As the potential of a next generation network (NGN) is recognised, telecommunication companies consider switching to it. Although the implementation of an NGN seems to be merely a modification of the network infrastructure, it may trigger or require changes in the whole company, because it builds upon the separation between service and transport, a flexible bundling of services to products and the streamlining of the IT infrastructure. We propose a holistic framework, structured into the layers 'strategy', 'processes' and 'information systems' and incorporate into each layer all concepts necessary for the implementation of an NGN, as well as the alignment of these concepts. As a first proof-of-concept for our framework we have performed a case study on the introduction of NGN in a large telecommunication company; we show that our framework captures all topics that are affected by an NGN implementation.}, language = {en} } @article{CzarneckiWinkelmannSpiliopoulou2013, author = {Czarnecki, Christian and Winkelmann, Axel and Spiliopoulou, Myra}, title = {Referenzprozessabl{\"a}ufe f{\"u}r Telekommunikationsunternehmen: Eine Erweiterung des eTOM-Modells}, series = {Wirtschaftsinformatik}, volume = {55}, journal = {Wirtschaftsinformatik}, number = {2}, publisher = {Springer Fachmedien}, address = {Wiesbaden}, issn = {1861-8936}, doi = {10.1007/s11576-013-0351-9}, pages = {83 -- 97}, year = {2013}, abstract = {Der Telekommunikationsmarkt erf{\"a}hrt substanzielle Ver{\"a}nderungen. Neue Gesch{\"a}ftsmodelle, innovative Dienstleistungen und Technologien erfordern Reengineering, Transformation und Prozessstandardisierung. Mit der Enhanced Telecom Operation Map (eTOM) bietet das TM Forum ein international anerkanntes de facto Referenz-Prozess-Framework basierend auf spezifischen Anforderungen und Auspr{\"a}gungen der Telekommunikationsindustrie an. Allerdings enth{\"a}lt dieses Referenz-Framework nur eine hierarchische Sammlung von Prozessen auf unterschiedlichen Abstraktionsebenen. Eine Kontrollsicht verstanden als sequenzielle Anordnung von Aktivit{\"a}ten und daraus resultierend ein realer Prozessablauf fehlt ebenso wie eine Ende-zu-Ende-Sicht auf den Kunden. In diesem Artikel erweitern wir das eTOM-Referenzmodell durch Referenzprozessabl{\"a}ufe, in welchen wir das Wissen {\"u}ber Prozesse in Telekommunikationsunternehmen abstrahieren und generalisieren. Durch die Referenzprozessabl{\"a}ufe werden Unternehmen bei dem strukturierten und transparenten (Re-)Design ihrer Prozesse unterst{\"u}tzt. Wir demonstrieren die Anwendbarkeit und N{\"u}tzlichkeit unserer Referenzprozessabl{\"a}ufe in zwei Fallstudien und evaluieren diese anhand von Kriterien f{\"u}r die Bewertung von Referenzmodellen. Die Referenzprozessabl{\"a}ufe wurden vom TM Forum in den Standard aufgenommen und als Teil von eTOM Version 9 ver{\"o}ffentlicht. Dar{\"u}ber hinaus diskutieren wir die Komponenten unseres Ansatzes, die auch außerhalb der Telekommunikationsindustrie angewandt werden k{\"o}nnen.}, language = {de} } @article{BensbergAuthCzarnecki2018, author = {Bensberg, Frank and Auth, Gunnar and Czarnecki, Christian}, title = {Einsatz von Text Analytics zur Unterst{\"u}tzung literaturintensiver Forschungsprozesse: Konzeption, Realisierung und Lessons Learned}, series = {Anwendungen und Konzepte der Wirtschaftsinformatik}, volume = {2018}, journal = {Anwendungen und Konzepte der Wirtschaftsinformatik}, number = {8}, publisher = {AKWI}, address = {Luzern}, issn = {2296-4592}, doi = {10.26034/lu.akwi.2018.3221}, pages = {1 -- 6}, year = {2018}, abstract = {Das anhaltende Wachstum wissenschaftlicher Ver{\"o}ffentlichungen wirft die Fragestellung auf, wie Literaturana-lysen im Rahmen von Forschungsprozessen digitalisiert und somit produktiver realisiert werden k{\"o}nnen. Insbesondere in informationstechnischen Fachgebieten ist die Forschungspraxis durch ein rasant wachsendes Publikationsaufkommen gekennzeichnet. Infolgedessen bietet sich der Einsatz von Methoden der Textanalyse (Text Analytics) an, die Textdaten automatisch vorbereiten und verarbeiten k{\"o}nnen. Erkenntnisse entstehen dabei aus Analysen von Wortarten und Subgruppen, Korrelations- sowie Zeitreihenanalysen. Dieser Beitrag stellt die Konzeption und Realisierung eines Prototypen vor, mit dem Anwender bibliographische Daten aus der etablierten Literaturdatenbank EBSCO Discovery Service mithilfe textanalytischer Methoden erschließen k{\"o}nnen. Der Prototyp basiert auf dem Analysesystem IBM Watson Explorer, das Hochschulen lizenzkostenfrei zur Verf{\"u}gung steht. Potenzielle Adressaten des Prototypen sind Forschungseinrichtungen, Beratungsunternehmen sowie Entscheidungstr{\"a}ger in Politik und Unternehmenspraxis.}, language = {de} } @article{CzarneckiBensbergAuth2019, author = {Czarnecki, Christian and Bensberg, Frank and Auth, Gunnar}, title = {Die Rolle von Softwarerobotern f{\"u}r die zuk{\"u}nftige Arbeitswelt}, series = {HMD Praxis der Wirtschaftsinformatik}, volume = {56}, journal = {HMD Praxis der Wirtschaftsinformatik}, number = {4}, publisher = {Springer}, address = {Cham}, issn = {2198-2775}, doi = {10.1365/s40702-019-00548-z}, pages = {795 -- 808}, year = {2019}, abstract = {Im Rahmen der Digitalisierung ist die zunehmende Automatisierung von bisher manuellen Prozessschritten ein Aspekt, der massive Auswirkungen auf die zuk{\"u}nftige Arbeitswelt haben wird. In diesem Kontext werden an den Einsatz von Softwarerobotern zur Prozessautomatisierung hohe Erwartungen gekn{\"u}pft. Bei den Implementierungsans{\"a}tzen wird die Diskussion aktuell insbesondere durch Robotic Process Automation (RPA) und Chatbots gepr{\"a}gt. Beide Ans{\"a}tze verfolgen das gemeinsame Ziel einer 1:1-Automatisierung von menschlichen Handlungen und dadurch ein direktes Ersetzen von Mitarbeitern durch Maschinen. Bei RPA werden Prozesse durch Softwareroboter erlernt und automatisiert ausgef{\"u}hrt. Dabei emulieren RPA-Roboter die Eingaben auf der bestehenden Pr{\"a}sentationsschicht, so dass keine {\"A}nderungen an vorhandenen Anwendungssystemen notwendig sind. Am Markt werden bereits unterschiedliche RPA-L{\"o}sungen als Softwareprodukte angeboten. Durch Chatbots werden Ein- und Ausgaben von Anwendungssystemen {\"u}ber nat{\"u}rliche Sprache realisiert. Dadurch ist die Automatisierung von unternehmensexterner Kommunikation (z. B. mit Kunden) aber auch von unternehmensinternen Assistenzt{\"a}tigkeiten m{\"o}glich. Der Beitrag diskutiert die Auswirkungen von Softwarerobotern auf die Arbeitswelt anhand von Anwendungsbeispielen und erl{\"a}utert die unternehmensindividuelle Entscheidung {\"u}ber den Einsatz von Softwarerobotern anhand von Effektivit{\"a}ts- und Effizienzzielen.}, language = {de} } @article{CzarneckiDietze2020, author = {Czarnecki, Christian and Dietze, Christian}, title = {Gestaltungsorientierte Forschung am Beispiel der Referenzmodellierung in der Telekommunikationsindustrie}, series = {HMD Praxis der Wirtschaftsinformatik}, volume = {57}, journal = {HMD Praxis der Wirtschaftsinformatik}, number = {2}, publisher = {Springer Nature}, address = {Cham}, issn = {2198-2775}, doi = {10.1365/s40702-020-00594-y}, pages = {310 -- 323}, year = {2020}, abstract = {Am Beispiel der Telekommunikationsindustrie zeigt der Beitrag eine konkrete Ausgestaltung anwendungsorientierter Forschung, die sowohl f{\"u}r die Praxis als auch f{\"u}r die Wissenschaft nutzen- und erkenntnisbringend ist. Forschungsgegenstand sind die Referenzmodelle des Industriegremiums TM Forum, die von vielen Telekommunikationsunternehmen zur Transformation ihrer Strukturen und Systeme genutzt werden. Es wird die langj{\"a}hrige Forschungst{\"a}tigkeit bei der Weiterentwicklung und Anwendung dieser Referenzmodelle beschrieben. Dabei wird ein konsequent gestaltungsorientierter Forschungsansatz verfolgt. Das Zusammenspiel aus kontinuierlicher Weiterentwicklung in Zusammenarbeit mit einem Industriegremium und der Anwendung in vielf{\"a}ltigen Praxisprojekten f{\"u}hrt zu einer erfolgreichen Symbiose aus praktischer Nutzengenerierung sowie wissenschaftlichem Erkenntnisgewinn. Der Beitrag stellt den gew{\"a}hlten Forschungsansatz anhand konkreter Beispiele vor. Darauf basierend werden Empfehlungen und Herausforderungen f{\"u}r eine gestaltungs- und praxisorientierte Forschung diskutiert.}, language = {de} } @article{BurgerRumpfDoetal.2021, author = {Burger, Ren{\´e} and Rumpf, Jessica and Do, Xuan Tung and Monakhova, Yulia and Diehl, Bernd W. K. and Rehahn, Matthias and Schulze, Margit}, title = {Is NMR combined with multivariate regression applicable for the molecular weight determination of randomly cross-linked polymers such as lignin?}, series = {ACS Omega}, volume = {6}, journal = {ACS Omega}, number = {44}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {2470-1343}, doi = {10.1021/acsomega.1c03574}, pages = {29516 -- 29524}, year = {2021}, abstract = {The molecular weight properties of lignins are one of the key elements that need to be analyzed for a successful industrial application of these promising biopolymers. In this study, the use of 1H NMR as well as diffusion-ordered spectroscopy (DOSY NMR), combined with multivariate regression methods, was investigated for the determination of the molecular weight (Mw and Mn) and the polydispersity of organosolv lignins (n = 53, Miscanthus x giganteus, Paulownia tomentosa, and Silphium perfoliatum). The suitability of the models was demonstrated by cross validation (CV) as well as by an independent validation set of samples from different biomass origins (beech wood and wheat straw). CV errors of ca. 7-9 and 14-16\% were achieved for all parameters with the models from the 1H NMR spectra and the DOSY NMR data, respectively. The prediction errors for the validation samples were in a similar range for the partial least squares model from the 1H NMR data and for a multiple linear regression using the DOSY NMR data. The results indicate the usefulness of NMR measurements combined with multivariate regression methods as a potential alternative to more time-consuming methods such as gel permeation chromatography.}, language = {en} } @article{MonakhovaDiehl2021, author = {Monakhova, Yulia and Diehl, Bernd W. K.}, title = {Simplification of NMR Workflows by Standardization Using 2H Integral of Deuterated Solvent as Applied to Aloe vera Preparations}, series = {Applied Magnetic Resonance}, volume = {52}, journal = {Applied Magnetic Resonance}, number = {11}, publisher = {Springer}, address = {Cham}, issn = {1613-7507}, doi = {10.1007/s00723-021-01393-4}, pages = {1591 -- 1600}, year = {2021}, abstract = {In this study, a recently proposed NMR standardization approach by 2H integral of deuterated solvent for quantitative multicomponent analysis of complex mixtures is presented. As a proof of principle, the existing NMR routine for the analysis of Aloe vera products was modified. Instead of using absolute integrals of targeted compounds and internal standard (nicotinamide) from 1H-NMR spectra, quantification was performed based on the ratio of a particular 1H-NMR compound integral and 2H-NMR signal of deuterated solvent D2O. Validation characteristics (linearity, repeatability, accuracy) were evaluated and the results showed that the method has the same precision as internal standardization in case of multicomponent screening. Moreover, a dehydration process by freeze drying is not necessary for the new routine. Now, our NMR profiling of A. vera products needs only limited sample preparation and data processing. The new standardization methodology provides an appealing alternative for multicomponent NMR screening. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and is recommended in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).}, language = {en} } @article{BurmistrovaSobolevaMonakhova2021, author = {Burmistrova, Natalia A. and Soboleva, Polina M. and Monakhova, Yulia}, title = {Is infrared spectroscopy combined with multivariate analysis a promising tool for heparin authentication?}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {194}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 113811}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {0731-7085}, doi = {10.1016/j.jpba.2020.113811}, year = {2021}, abstract = {The investigation of the possibility to determine various characteristics of powder heparin (n = 115) was carried out with infrared spectroscopy. The evaluation of heparin samples included several parameters such as purity grade, distributing company, animal source as well as heparin species (i.e. Na-heparin, Ca-heparin, and heparinoids). Multivariate analysis using principal component analysis (PCA), soft independent modelling of class analogy (SIMCA), and partial least squares - discriminant analysis (PLS-DA) were applied for the modelling of spectral data. Different pre-processing methods were applied to IR spectral data; multiplicative scatter correction (MSC) was chosen as the most relevant. Obtained results were confirmed by nuclear magnetic resonance (NMR) spectroscopy. Good predictive ability of this approach demonstrates the potential of IR spectroscopy and chemometrics for screening of heparin quality. This approach, however, is designed as a screening tool and is not considered as a replacement for either of the methods required by USP and FDA.}, language = {en} } @article{MonakhovaDiehl2021, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Novel approach of qNMR workflow by standardization using 2H integral: Application to any intrinsic calibration standard}, series = {Talanta}, volume = {222}, journal = {Talanta}, number = {Article number: 121504}, publisher = {Elsevier}, isbn = {0039-9140}, doi = {10.1016/j.talanta.2020.121504}, year = {2021}, abstract = {Quantitative nuclear magnetic resonance (qNMR) is routinely performed by the internal or external standardization. The manuscript describes a simple alternative to these common workflows by using NMR signal of another active nuclei of calibration compound. For example, for any arbitrary compound quantification by NMR can be based on the use of an indirect concentration referencing that relies on a solvent having both 1H and 2H signals. To perform high-quality quantification, the deuteration level of the utilized deuterated solvent has to be estimated. In this contribution the new method was applied to the determination of deuteration levels in different deuterated solvents (MeOD, ACN, CDCl3, acetone, benzene, DMSO-d6). Isopropanol-d6, which contains a defined number of deuterons and protons, was used for standardization. Validation characteristics (precision, accuracy, robustness) were calculated and the results showed that the method can be used in routine practice. Uncertainty budget was also evaluated. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and can be applied in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).}, language = {en} } @article{MonakhovaSobolevaFedotovaetal.2022, author = {Monakhova, Yulia and Soboleva, Polina M. and Fedotova, Elena S. and Musina, Kristina T. and Burmistrova, Natalia A.}, title = {Quantum chemical calculations of IR spectra of heparin disaccharide subunits}, series = {Computational and Theoretical Chemistry}, volume = {1217}, journal = {Computational and Theoretical Chemistry}, number = {Article number: 113891}, publisher = {Elsevier}, address = {New York, NY}, isbn = {2210-271X}, doi = {10.1016/j.comptc.2022.113891}, year = {2022}, abstract = {Heparin is a natural polysaccharide, which plays essential role in many biological processes. Alterations in building blocks can modify biological roles of commercial heparin products, due to significant changes in the conformation of the polymer chain. The variability structure of heparin leads to difficulty in quality control using different analytical methods, including infrared (IR) spectroscopy. In this paper molecular modelling of heparin disaccharide subunits was performed using quantum chemistry. The structural and spectral parameters of these disaccharides have been calculated using RHF/6-311G. In addition, over-sulphated chondroitin sulphate disaccharide was studied as one of the most widespread contaminants of heparin. Calculated IR spectra were analyzed with respect to specific structure parameters. IR spectroscopic fingerprint was found to be sensitive to substitution pattern of disaccharide subunits. Vibrational assignments of calculated spectra were correlated with experimental IR spectral bands of native heparin. Chemometrics was used to perform multivariate analysis of simulated spectral data.}, language = {en} } @article{BurgerLindnerRumpfetal.2022, author = {Burger, Ren{\´e} and Lindner, Simon and Rumpf, Jessica and Do, Xuan Tung and Diehl, Bernd W.K. and Rehahn, Matthias and Monakhova, Yulia and Schulze, Margit}, title = {Benchtop versus high field NMR: Comparable performance found for the molecular weight determination of lignin}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {212}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114649}, publisher = {Elsevier}, address = {New York, NY}, isbn = {0731-7085}, doi = {10.1016/j.jpba.2022.114649}, year = {2022}, abstract = {Lignin is a promising renewable biopolymer being investigated worldwide as an environmentally benign substitute of fossil-based aromatic compounds, e.g. for the use as an excipient with antioxidant and antimicrobial properties in drug delivery or even as active compound. For its successful implementation into process streams, a quick, easy, and reliable method is needed for its molecular weight determination. Here we present a method using 1H spectra of benchtop as well as conventional NMR systems in combination with multivariate data analysis, to determine lignin's molecular weight (Mw and Mn) and polydispersity index (PDI). A set of 36 organosolv lignin samples (from Miscanthus x giganteus, Paulownia tomentosa and Silphium perfoliatum) was used for the calibration and cross validation, and 17 samples were used as external validation set. Validation errors between 5.6\% and 12.9\% were achieved for all parameters on all NMR devices (43, 60, 500 and 600 MHz). Surprisingly, no significant difference in the performance of the benchtop and high-field devices was found. This facilitates the application of this method for determining lignin's molecular weight in an industrial environment because of the low maintenance expenditure, small footprint, ruggedness, and low cost of permanent magnet benchtop NMR systems.}, language = {en} } @article{MonakhovaDiehl2022, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Multinuclear NMR screening of pharmaceuticals using standardization by 2H integral of a deuterated solvent}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {209}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114530}, publisher = {Elsevier}, isbn = {0731-7085}, doi = {10.1016/j.jpba.2021.114530}, year = {2022}, abstract = {NMR standardization approach that uses the 2H integral of deuterated solvent for quantitative multinuclear analysis of pharmaceuticals is described. As a proof of principle, the existing NMR procedure for the analysis of heparin products according to US Pharmacopeia monograph is extended to the determination of Na+ and Cl- content in this matrix. Quantification is performed based on the ratio of a 23Na (35Cl) NMR integral and 2H NMR signal of deuterated solvent, D2O, acquired using the specific spectrometer hardware. As an alternative, the possibility of 133Cs standardization using the addition of Cs2CO3 stock solution is shown. Validation characteristics (linearity, repeatability, sensitivity) are evaluated. A holistic NMR profiling of heparin products can now also be used for the quantitative determination of inorganic compounds in a single analytical run using a single sample. In general, the new standardization methodology provides an appealing alternative for the NMR screening of inorganic and organic components in pharmaceutical products.}, language = {en} } @article{LindnerBurgerRutledgeetal.2022, author = {Lindner, Simon and Burger, Ren{\´e} and Rutledge, Douglas N. and Do, Xuan Tung and Rumpf, Jessica and Diehl, Bernd W. K. and Schulze, Margit and Monakhova, Yulia}, title = {Is the calibration transfer of multivariate calibration models between high- and low-field NMR instruments possible? A case study of lignin molecular weight}, series = {Analytical chemistry}, volume = {94}, journal = {Analytical chemistry}, number = {9}, publisher = {ACS Publications}, address = {Washington, DC}, isbn = {1520-6882}, doi = {10.1021/acs.analchem.1c05125}, pages = {3997 -- 4004}, year = {2022}, abstract = {Although several successful applications of benchtop nuclear magnetic resonance (NMR) spectroscopy in quantitative mixture analysis exist, the possibility of calibration transfer remains mostly unexplored, especially between high- and low-field NMR. This study investigates for the first time the calibration transfer of partial least squares regressions [weight average molecular weight (Mw) of lignin] between high-field (600 MHz) NMR and benchtop NMR devices (43 and 60 MHz). For the transfer, piecewise direct standardization, calibration transfer based on canonical correlation analysis, and transfer via the extreme learning machine auto-encoder method are employed. Despite the immense resolution difference between high-field and low-field NMR instruments, the results demonstrate that the calibration transfer from high- to low-field is feasible in the case of a physical property, namely, the molecular weight, achieving validation errors close to the original calibration (down to only 1.2 times higher root mean square errors). These results introduce new perspectives for applications of benchtop NMR, in which existing calibrations from expensive high-field instruments can be transferred to cheaper benchtop instruments to economize.}, language = {en} } @article{Maurischat2022, author = {Maurischat, Andreas}, title = {Algebraic independence of the Carlitz period and its hyperderivatives}, series = {Journal of Number Theory}, volume = {240}, journal = {Journal of Number Theory}, publisher = {Elsevier}, address = {Orlando, Fla.}, issn = {0022-314X}, doi = {10.1016/j.jnt.2022.01.006}, pages = {145 -- 162}, year = {2022}, language = {en} } @article{KotliarOrtnerConradietal.2022, author = {Kotliar, Konstantin and Ortner, Marion and Conradi, Anna and Hacker, Patricia and Hauser, Christine and G{\"u}nthner, Roman and Moser, Michaela and Muggenthaler, Claudia and Diehl-Schmid, Janine and Priller, Josef and Schmaderer, Christoph and Grimmer, Timo}, title = {Altered retinal cerebral vessel oscillation frequencies in Alzheimer's disease compatible with impaired amyloid clearance}, series = {Neurobiology of Aging}, volume = {120}, journal = {Neurobiology of Aging}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0197-4580}, doi = {10.1016/j.neurobiolaging.2022.08.012}, pages = {117 -- 127}, year = {2022}, abstract = {Retinal vessels are similar to cerebral vessels in their structure and function. Moderately low oscillation frequencies of around 0.1 Hz have been reported as the driving force for paravascular drainage in gray matter in mice and are known as the frequencies of lymphatic vessels in humans. We aimed to elucidate whether retinal vessel oscillations are altered in Alzheimer's disease (AD) at the stage of dementia or mild cognitive impairment (MCI). Seventeen patients with mild-to-moderate dementia due to AD (ADD); 23 patients with MCI due to AD, and 18 cognitively healthy controls (HC) were examined using Dynamic Retinal Vessel Analyzer. Oscillatory temporal changes of retinal vessel diameters were evaluated using mathematical signal analysis. Especially at moderately low frequencies around 0.1 Hz, arterial oscillations in ADD and MCI significantly prevailed over HC oscillations and correlated with disease severity. The pronounced retinal arterial vasomotion at moderately low frequencies in the ADD and MCI groups would be compatible with the view of a compensatory upregulation of paravascular drainage in AD and strengthen the amyloid clearance hypothesis.}, language = {en} } @article{ColomboDriraFrotscheretal.2022, author = {Colombo, Daniele and Drira, Slah and Frotscher, Ralf and Staat, Manfred}, title = {An element-based formulation for ES-FEM and FS-FEM models for implementation in standard solid mechanics finite element codes for 2D and 3D static analysis}, series = {International Journal for Numerical Methods in Engineering}, volume = {124}, journal = {International Journal for Numerical Methods in Engineering}, number = {2}, publisher = {Wiley}, address = {Chichester}, issn = {1097-0207}, doi = {10.1002/nme.7126}, pages = {402 -- 433}, year = {2022}, abstract = {Edge-based and face-based smoothed finite element methods (ES-FEM and FS-FEM, respectively) are modified versions of the finite element method allowing to achieve more accurate results and to reduce sensitivity to mesh distortion, at least for linear elements. These properties make the two methods very attractive. However, their implementation in a standard finite element code is nontrivial because it requires heavy and extensive modifications to the code architecture. In this article, we present an element-based formulation of ES-FEM and FS-FEM methods allowing to implement the two methods in a standard finite element code with no modifications to its architecture. Moreover, the element-based formulation permits to easily manage any type of element, especially in 3D models where, to the best of the authors' knowledge, only tetrahedral elements are used in FS-FEM applications found in the literature. Shape functions for non-simplex 3D elements are proposed in order to apply FS-FEM to any standard finite element.}, language = {en} } @article{BhattaraiMayStaatetal.2022, author = {Bhattarai, Aroj and May, Charlotte Anabell and Staat, Manfred and Kowalczyk, Wojciech and Tran, Thanh Ngoc}, title = {Layer-specific damage modeling of porcine large intestine under biaxial tension}, series = {Bioengineering}, volume = {9}, journal = {Bioengineering}, number = {10, Early Access}, publisher = {MDPI}, address = {Basel}, issn = {2306-5354}, doi = {10.3390/bioengineering9100528}, pages = {1 -- 17}, year = {2022}, abstract = {The mechanical behavior of the large intestine beyond the ultimate stress has never been investigated. Stretching beyond the ultimate stress may drastically impair the tissue microstructure, which consequently weakens its healthy state functions of absorption, temporary storage, and transportation for defecation. Due to closely similar microstructure and function with humans, biaxial tensile experiments on the porcine large intestine have been performed in this study. In this paper, we report hyperelastic characterization of the large intestine based on experiments in 102 specimens. We also report the theoretical analysis of the experimental results, including an exponential damage evolution function. The fracture energies and the threshold stresses are set as damage material parameters for the longitudinal muscular, the circumferential muscular and the submucosal collagenous layers. A biaxial tensile simulation of a linear brick element has been performed to validate the applicability of the estimated material parameters. The model successfully simulates the biomechanical response of the large intestine under physiological and non-physiological loads.}, language = {en} } @article{PhilippEfthimiouPaganoetal.2022, author = {Philipp, Mohr and Efthimiou, Nikos and Pagano, Fiammetta and Kratochwil, Nicolaus and Pizzichemi, Marco and Tsoumpas, Charalampos and Auffray, Etiennette and Ziemons, Karl}, title = {Image reconstruction analysis for positron emission tomography with heterostructured scintillators}, series = {IEEE Transactions on Radiation and Plasma Medical Sciences}, volume = {7}, journal = {IEEE Transactions on Radiation and Plasma Medical Sciences}, number = {1}, publisher = {IEEE}, address = {New York, NY}, issn = {2469-7311}, doi = {10.1109/TRPMS.2022.3208615}, pages = {41 -- 51}, year = {2022}, abstract = {The concept of structure engineering has been proposed for exploring the next generation of radiation detectors with improved performance. A TOF-PET geometry with heterostructured scintillators with a pixel size of 3.0×3.1×15 mm3 was simulated using Monte Carlo. The heterostructures consisted of alternating layers of BGO as a dense material with high stopping power and plastic (EJ232) as a fast light emitter. The detector time resolution was calculated as a function of the deposited and shared energy in both materials on an event-by-event basis. While sensitivity was reduced to 32\% for 100 μm thick plastic layers and 52\% for 50 μm, the CTR distribution improved to 204±49 ps and 220±41 ps respectively, compared to 276 ps that we considered for bulk BGO. The complex distribution of timing resolutions was accounted for in the reconstruction. We divided the events into three groups based on their CTR and modeled them with different Gaussian TOF kernels. On a NEMA IQ phantom, the heterostructures had better contrast recovery in early iterations. On the other hand, BGO achieved a better contrast to noise ratio (CNR) after the 15th iteration due to the higher sensitivity. The developed simulation and reconstruction methods constitute new tools for evaluating different detector designs with complex time responses.}, language = {en} } @article{EngelmannPourshahidiShalabyetal.2022, author = {Engelmann, Ulrich M. and Pourshahidi, Mohammad Ali and Shalaby, Ahmed and Krause, Hans-Joachim}, title = {Probing particle size dependency of frequency mixing magnetic detection with dynamic relaxation simulation}, series = {Journal of Magnetism and Magnetic Materials}, volume = {563}, journal = {Journal of Magnetism and Magnetic Materials}, number = {In progress, Art. No. 169965}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-8853}, doi = {10.1016/j.jmmm.2022.169965}, year = {2022}, abstract = {Biomedical applications of magnetic nanoparticles (MNP) fundamentally rely on the particles' magnetic relaxation as a response to an alternating magnetic field. The magnetic relaxation complexly depends on the interplay of MNP magnetic and physical properties with the applied field parameters. It is commonly accepted that particle core size is a major contributor to signal generation in all the above applications, however, most MNP samples comprise broad distribution spanning nm and more. Therefore, precise knowledge of the exact contribution of individual core sizes to signal generation is desired for optimal MNP design generally for each application. Specifically, we present a magnetic relaxation simulation-driven analysis of experimental frequency mixing magnetic detection (FMMD) for biosensing to quantify the contributions of individual core size fractions towards signal generation. Applying our method to two different experimental MNP systems, we found the most dominant contributions from approx. 20 nm sized particles in the two independent MNP systems. Additional comparison between freely suspended and immobilized MNP also reveals insight in the MNP microstructure, allowing to use FMMD for MNP characterization, as well as to further fine-tune its applicability in biosensing.}, language = {en} } @article{PourshahidiEngelmannOffenhaeusseretal.2022, author = {Pourshahidi, Ali Mohammad and Engelmann, Ulrich M. and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim}, title = {Resolving ambiguities in core size determination of magnetic nanoparticles from magnetic frequency mixing data}, series = {Journal of Magnetism and Magnetic Materials}, volume = {563}, journal = {Journal of Magnetism and Magnetic Materials}, number = {In progress, Art. No. 169969}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-8853}, doi = {10.1016/j.jmmm.2022.169969}, year = {2022}, abstract = {Frequency mixing magnetic detection (FMMD) has been widely utilized as a measurement technique in magnetic immunoassays. It can also be used for the characterization and distinction (also known as "colourization") of different types of magnetic nanoparticles (MNPs) based on their core sizes. In a previous work, it was shown that the large particles contribute most of the FMMD signal. This leads to ambiguities in core size determination from fitting since the contribution of the small-sized particles is almost undetectable among the strong responses from the large ones. In this work, we report on how this ambiguity can be overcome by modelling the signal intensity using the Langevin model in thermodynamic equilibrium including a lognormal core size distribution fL(dc,d0,σ) fitted to experimentally measured FMMD data of immobilized MNPs. For each given median diameter d0, an ambiguous amount of best-fitting pairs of parameters distribution width σ and number of particles Np with R2 > 0.99 are extracted. By determining the samples' total iron mass, mFe, with inductively coupled plasma optical emission spectrometry (ICP-OES), we are then able to identify the one specific best-fitting pair (σ, Np) one uniquely. With this additional externally measured parameter, we resolved the ambiguity in core size distribution and determined the parameters (d0, σ, Np) directly from FMMD measurements, allowing precise MNPs sample characterization.}, language = {en} } @article{SteuerDankertGilmartinMulleretal.2019, author = {Steuer-Dankert, Linda and Gilmartin, Shannon K. and Muller, Carol B. and Dungs, Carolin and Sheppard, Sheri and Leicht-Scholten, Carmen}, title = {Expanding engineering limits : a concept for socially responsible education of engineers}, series = {The international journal of engineering education}, volume = {35}, journal = {The international journal of engineering education}, number = {2}, isbn = {0949-149X}, pages = {658 -- 673}, year = {2019}, language = {en} } @article{SteuerDankertSharmaBlecketal.2017, author = {Steuer-Dankert, Linda and Sharma, Mamta Rameshwarlal and Bleck, Wolfgang and Leicht-Scholten, Carmen}, title = {Diversity and innovation management in large research groups}, series = {International Journal of Innovation Management}, volume = {5}, journal = {International Journal of Innovation Management}, number = {2}, issn = {1757-5877}, pages = {49 -- 72}, year = {2017}, abstract = {Contemporary research appreciates a diverse workforce as a potential source of innovation. Researchers explore the fine details of why diversity management is central for generating innovations in heterogeneous research groups and how it could be effectively implemented into organizations. Complex research associations that discuss topics with a high impact on society increasingly address the necessity of establishing a diverse workforce to confront the challenges of tomorrow. Characterized by complex management structures as well as hierarchies, research associations have not been a subject of investigation until now. For this reason, the presented research project aims to develop a diversity and innovation management strategy with the ultimate goal of inducing change in the corporate culture. The proposed approach consisted of six phases; the first two phases investigated the status quo of diversity in the existing organizational structures of member institutes and the variety of particular working cultures within the research association. The third and the fourth phases utilized qualitative and quantitative studies. The third phase focused on the connection of management level to diversity and innovation, and the need for diversity and innovation management, and tailor-made methods of implementing them. The first three phases have been accomplished successfully; preliminary results are already available. The fourth phase will mainly focus on exploring the mind-set of the employees. The fifth phase will consolidate the findings in the first four phases into an implementable strategy. The final phase will address the implementation of this strategy into the organization. Phases 4 to 6 have not yet been undertaken}, language = {en} } @article{MonakhovaDiehl2022, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Nuclear magnetic resonance spectroscopy as an elegant tool for a complete quality control of crude heparin material}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {219}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114915}, publisher = {Elsevier}, address = {New York, NY}, issn = {0731-7085}, doi = {10.1016/j.jpba.2022.114915}, year = {2022}, abstract = {Nuclear magnetic resonance (NMR) spectrometric methods for the quantitative analysis of pure heparin in crude heparin is proposed. For quantification, a two-step routine was developed using a USP heparin reference sample for calibration and benzoic acid as an internal standard. The method was successfully validated for its accuracy, reproducibility, and precision. The methodology was used to analyze 20 authentic porcine heparinoid samples having heparin content between 4.25 w/w \% and 64.4 w/w \%. The characterization of crude heparin products was further extended to a simultaneous analysis of these common ions: sodium, calcium, acetate and chloride. A significant, linear dependence was found between anticoagulant activity and assayed heparin content for thirteen heparinoids samples, for which reference data were available. A Diffused-ordered NMR experiment (DOSY) can be used for qualitative analysis of specific glycosaminoglycans (GAGs) in heparinoid matrices and, potentially, for quantitative prediction of molecular weight of GAGs. NMR spectrometry therefore represents a unique analytical method suitable for the simultaneous quantitative control of organic and inorganic composition of crude heparin samples (especially heparin content) as well as an estimation of other physical and quality parameters (molecular weight, animal origin and activity).}, language = {en} } @article{Kurz2018, author = {Kurz, Melanie}, title = {Was heißt: Verantwortung im Design? Historische Positionen}, series = {Boxhorn: das Magazin aus dem Fachbereich Gestaltung der FH Aachen}, journal = {Boxhorn: das Magazin aus dem Fachbereich Gestaltung der FH Aachen}, number = {34}, address = {Aachen}, pages = {26 -- 33}, year = {2018}, language = {de} } @article{Kurz2019, author = {Kurz, Melanie}, title = {Images of Sweden in Germany: from Sundborn and Bullerby to Ikea}, series = {nomad: the magazine for new design culture, business affairs and contemporary lifestyle}, journal = {nomad: the magazine for new design culture, business affairs and contemporary lifestyle}, number = {8}, isbn = {2513-0714}, pages = {136 -- 147}, year = {2019}, language = {en} } @article{UysalCreutzFiratetal.2022, author = {Uysal, Karya and Creutz, Till and Firat, Ipek Seda and Artmann, Gerhard and Teusch, Nicole and Temiz Artmann, Ayseg{\"u}l}, title = {Bio-functionalized ultra-thin, large-area and waterproof silicone membranes for biomechanical cellular loading and compliance experiments}, series = {Polymers}, volume = {14}, journal = {Polymers}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, pages = {2213}, year = {2022}, abstract = {Biocompatibility, flexibility and durability make polydimethylsiloxane (PDMS) membranes top candidates in biomedical applications. CellDrum technology uses large area, <10 µm thin membranes as mechanical stress sensors of thin cell layers. For this to be successful, the properties (thickness, temperature, dust, wrinkles, etc.) must be precisely controlled. The following parameters of membrane fabrication by means of the Floating-on-Water (FoW) method were investigated: (1) PDMS volume, (2) ambient temperature, (3) membrane deflection and (4) membrane mechanical compliance. Significant differences were found between all PDMS volumes and thicknesses tested (p < 0.01). They also differed from the calculated values. At room temperatures between 22 and 26 °C, significant differences in average thickness values were found, as well as a continuous decrease in thicknesses within a 4 °C temperature elevation. No correlation was found between the membrane thickness groups (between 3-4 µm) in terms of deflection and compliance. We successfully present a fabrication method for thin bio-functionalized membranes in conjunction with a four-step quality management system. The results highlight the importance of tight regulation of production parameters through quality control. The use of membranes described here could also become the basis for material testing on thin, viscous layers such as polymers, dyes and adhesives, which goes far beyond biological applications.}, language = {en} } @article{BuedenbenderJanssenWobben2009, author = {B{\"u}denbender, Martin and Janssen, Matthias and Wobben, Magnus}, title = {Versorgungssicherheit auf Elektrizit{\"a}tsm{\"a}rkten — Investitionsdilemma durch ineffizientes Marktdesign?}, series = {Zeitschrift f{\"u}r Energiewirtschaft}, volume = {33}, journal = {Zeitschrift f{\"u}r Energiewirtschaft}, number = {1}, issn = {1866-2765}, pages = {49 -- 61}, year = {2009}, abstract = {Dieser Artikel befasst sich mit dem Investitionsdilemma in der Stromerzeugung, welches in unzureichend ausgestalteten liberalisierten Stromm{\"a}rkten zu einem gesamtwirtschaftlich unerw{\"u}nscht geringen Niveau an Versorgungssicherheit f{\"u}hrt. Die origin{\"a}ren Ursachen im deutschen Strommarkt liegen in einer eingeschr{\"a}nkten Schadenersatzpflicht der Lieferanten im Falle eines kapazit{\"a}tsbedingten Stromausfalls und in der zeitlichen Differenz zwischen letzter Handelsm{\"o}glichkeit und Lieferung. Letzteres verhindert ein jederzeitiges individuelles Glattstellen von unerwartet auftretenden Ein- bzw. Ausspeise{\"a}nderungen. Des Weiteren f{\"u}hren Faktoren wie die fehlende Partizipation der Endverbraucher am Großhandelsmarkt, die nur undifferenziert m{\"o}gliche Abschaltung von Endverbrauchern oder time lags durch lange Bau- und Genehmigungszeiten von Erzeugungskapazit{\"a}ten in Verbindung mit {\"u}ber lange Zeitr{\"a}ume nicht versicherbaren Risiken bez{\"u}glich Brennstoff-, CO2-Zertifikate- und Strompreisen zu einer Versch{\"a}rfung der Problematik. Sinnvolle L{\"o}sungsans{\"a}tze sind zum einen die Erh{\"o}hung der Intraday-Handelsliquidit{\"a}t zur Verbesserung der Marktr{\"a}umungsfunktion bis m{\"o}glichst kurz vor Stromlieferung, was z. B. durch eine F{\"o}rderung der Direktvermarktung Erneuerbarer Energien erreicht werden kann. Zum anderen tr{\"a}gt ein verst{\"a}rkter Ausbau von smart metern bei Endverbrauchern zu einer h{\"o}heren Versorgungssicherheit bei, da dies die Gl{\"a}ttung von Lastspitzen und die Artikulation der tats{\"a}chlichen Zahlungsbereitschaft von Endverbrauchern am Großhandelsmarkt erm{\"o}glicht.}, language = {de} } @article{Buedenbender2009, author = {B{\"u}denbender, Martin}, title = {Der Atomausstieg in Deutschland - ein zukunftsf{\"a}higer Sonderweg im europ{\"a}ischen Kontext?}, series = {atw International Journal for Nuclear Power}, volume = {54}, journal = {atw International Journal for Nuclear Power}, number = {10}, publisher = {Inforum}, address = {Berlin}, issn = {14315254}, pages = {616 -- 627}, year = {2009}, language = {de} } @article{Buedenbender2009, author = {B{\"u}denbender, Martin}, title = {Auswirkungen der europ{\"a}ischen Energiepolitik auf den deutschen Atomausstieg}, series = {Zeitschrift f{\"u}r Energiewirtschaft}, volume = {33}, journal = {Zeitschrift f{\"u}r Energiewirtschaft}, number = {4}, publisher = {Vieweg}, address = {Wiesbaden}, isbn = {1866-2765}, doi = {10.1007/s12398-009-0039-4}, pages = {341 -- 350}, year = {2009}, abstract = {Nach der Bundestagswahl am 27. September 2009 steht der Atomausstieg in Deutschland wieder ganz oben auf der politischen Agenda. Eine aktuelle Bestandsaufnahme aller ma\geblichen Argumente erscheint somit zwingend notwendig. Dabei sollte der Blickwinkel nicht national beschr{\"a}nkt bleiben, sondern vor allem der Einfluss der europ{\"a}ischen Dimension dieser Thematik miteinbezogen werden. Auf europ{\"a}ischer Ebene zeigt sich eine Position zu Gunsten der Kernenergie. Unter den 27 EU-Staaten findet gerade eine Renaissance der Atomkraft statt. Die drei europ{\"a}ischen Organe bef{\"u}rworten den umfangreichen Einsatz der Kernenergie als langfristigen Bestandteil des Energietr{\"a}germix. Deutschland geh{\"o}rt mit seinem Beschluss zum Atomausstieg einer Minderheit an. Als Teil eines immer st{\"a}rker zusammen wachsenden und letztendlich vollst{\"a}ndig integrierten europ{\"a}ischen Strommarktes wird Deutschland langfristig stets mit Atomstrom versorgt werden. Dies gilt losgel{\"o}st von dem Einsatz von Kernkraftwerken im Inland. Eine Abschaltung der Anlagen f{\"u}hrt damit nicht zur Zielerreichung der Atomkraftgegner, sondern lediglich zu zus{\"a}tzlichen energietechnischen Herausforderungen bei der Sicherstellung der deutschen Stromversorgung. Der deutsche Atomausstieg sollte aus diesem Grund von der neuen Bundesregierung zur{\"u}ck genommen werden.}, language = {de} } @article{SchneiderSchwabedalBialonski2022, author = {Schneider, Jules and Schwabedal, Justus T. C. and Bialonski, Stephan}, title = {Schlafspindeln - Funktion, Detektion und Nutzung als Biomarker f{\"u}r die psychiatrische Diagnostik}, series = {Der Nervenarzt}, journal = {Der Nervenarzt}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {1433-0407}, doi = {10.1007/s00115-022-01340-z}, pages = {1 -- 8}, year = {2022}, abstract = {Hintergrund: Die Schlafspindel ist ein Graphoelement des Elektroenzephalogramms (EEG), das im Leicht- und Tiefschlaf beobachtet werden kann. Ver{\"a}nderungen der Spindelaktivit{\"a}t wurden f{\"u}r verschiedene psychiatrische Erkrankungen beschrieben. Schlafspindeln zeigen aufgrund ihrer relativ konstanten Eigenschaften Potenzial als Biomarker in der psychiatrischen Diagnostik. Methode: Dieser Beitrag liefert einen {\"U}berblick {\"u}ber den Stand der Wissenschaft zu Eigenschaften und Funktionen der Schlafspindeln sowie {\"u}ber beschriebene Ver{\"a}nderungen der Spindelaktivit{\"a}t bei psychiatrischen Erkrankungen. Verschiedene methodische Ans{\"a}tze und Ausblicke zur Spindeldetektion werden hinsichtlich deren Anwendungspotenzial in der psychiatrischen Diagnostik erl{\"a}utert. Ergebnisse und Schlussfolgerung: W{\"a}hrend Ver{\"a}nderungen der Spindelaktivit{\"a}t bei psychiatrischen Erkrankungen beschrieben wurden, ist deren exaktes Potenzial f{\"u}r die psychiatrische Diagnostik noch nicht ausreichend erforscht. Diesbez{\"u}glicher Erkenntnisgewinn wird in der Forschung gegenw{\"a}rtig durch ressourcenintensive und fehleranf{\"a}llige Methoden zur manuellen oder automatisierten Spindeldetektion ausgebremst. Neuere Detektionsans{\"a}tze, die auf Deep-Learning-Verfahren basieren, k{\"o}nnten die Schwierigkeiten bisheriger Detektionsmethoden {\"u}berwinden und damit neue M{\"o}glichkeiten f{\"u}r die praktisch}, language = {de} } @article{HeuermannEmmrichBongartz2022, author = {Heuermann, Holger and Emmrich, Thomas and Bongartz, Simon}, title = {Microwave spark plug to support ignitions with high compression ratios}, series = {IEEE Transactions on Plasma Science}, journal = {IEEE Transactions on Plasma Science}, number = {Early Access}, publisher = {IEEE}, issn = {1939-9375}, doi = {10.1109/TPS.2022.3183690}, pages = {1 -- 6}, year = {2022}, abstract = {Upcoming gasoline engines should run with a larger number of fuels beginning from petrol over methanol up to gas by a wide range of compression ratios and a homogeneous charge. In this article, the microwave (MW) spark plug, based on a high-speed frequency hopping system, is introduced as a solution, which can support a nitrogen compression ratio up to 1:39 in a chamber and more. First, an overview of the high-speed frequency hopping MW ignition and operation system as well as the large number of applications are presented. Both gives an understanding of this new base technology for MW plasma generation. Focus of the theoretical part is the explanation of the internal construction of the spark plug, on the achievable of the high voltage generation as well as the high efficiency to hold the plasma. In detail, the development process starting with circuit simulations and ending with the numerical multiphysics field simulations is described. The concept is evaluated with a reference prototype covering the frequency range between 2.40 and 2.48 GHz and working over a large power range from 20 to 200 W. A larger number of different measurements starting by vector hot-S11 measurements and ending by combined working scenarios out of hot temperature, high pressure and charge motion are winding up the article. The limits for the successful pressure tests were given by the pressure chamber. Pressures ranged from 1 to 39 bar and charge motion up to 25 m/s as well as temperatures from 30◦ to 125◦.}, language = {en} } @article{EmhardtJarodzkaBrandGruweletal.2022, author = {Emhardt, Selina N. and Jarodzka, Halszka and Brand-Gruwel, Saskia and Drumm, Christian and Niehorster, Diederick C. and van Gog, Tamara}, title = {What is my teacher talking about? Effects of displaying the teacher's gaze and mouse cursor cues in video lectures on students' learning}, series = {Journal of Cognitive Psychology}, journal = {Journal of Cognitive Psychology}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {2044-5911}, doi = {10.1080/20445911.2022.2080831}, pages = {1 -- 19}, year = {2022}, abstract = {Eye movement modelling examples (EMME) are instructional videos that display a teacher's eye movements as "gaze cursor" (e.g. a moving dot) superimposed on the learning task. This study investigated if previous findings on the beneficial effects of EMME would extend to online lecture videos and compared the effects of displaying the teacher's gaze cursor with displaying the more traditional mouse cursor as a tool to guide learners' attention. Novices (N = 124) studied a pre-recorded video lecture on how to model business processes in a 2 (mouse cursor absent/present) × 2 (gaze cursor absent/present) between-subjects design. Unexpectedly, we did not find significant effects of the presence of gaze or mouse cursors on mental effort and learning. However, participants who watched videos with the gaze cursor found it easier to follow the teacher. Overall, participants responded positively to the gaze cursor, especially when the mouse cursor was not displayed in the video.}, language = {en} } @article{Wolf2000, author = {Wolf, Martin}, title = {Groupware related task design}, series = {ACM SIGGROUP Bulletin}, volume = {21}, journal = {ACM SIGGROUP Bulletin}, number = {2}, issn = {2372-7403}, doi = {10.1145/605660.605662}, pages = {5 -- 8}, year = {2000}, abstract = {his report summarizes the results of a workshop on Groupware related task design which took place at the International Conference on Supporting Group Work Group'99, Arizona, from 14 th to 17 th November 1999. The workshop was addressed to people from different viewpoints, backgrounds, and domains: - Researchers dealing with questions of task analysis and task modeling for Groupware application from an academic point of view. They may contribute modelbased design approaches or theoretically oriented work - Practitioners with experience in the design and everyday use of groupware systems. They might refer to the practical side of the topic: "real" tasks, "real" problems, "real" users, etc.}, language = {en} } @article{ChloeMalyaranCraveiroetal.2022, author = {Chlo{\´e}, Radermacher and Malyaran, Hanna and Craveiro, Rogerio Bastos and Peglow, Sarah and Behbahani, Mehdi and Pufe, Thomas and Wolf, Michael and Neuss, Sabine}, title = {Mechanical loading on cementoblasts: a mini review}, series = {Osteologie}, volume = {31}, journal = {Osteologie}, number = {2}, publisher = {Thieme}, address = {Stuttgart}, issn = {1019-1291}, doi = {10.1055/a-1826-0777}, pages = {111 -- 118}, year = {2022}, abstract = {Orthodontic treatments are concomitant with mechanical forces and thereby cause teeth movements. The applied forces are transmitted to the tooth root and the periodontal ligaments which is compressed on one side and tensed up on the other side. Indeed, strong forces can lead to tooth root resorption and the crown-to-tooth ratio is reduced with the potential for significant clinical impact. The cementum, which covers the tooth root, is a thin mineralized tissue of the periodontium that connects the periodontal ligament with the tooth and is build up by cementoblasts. The impact of tension and compression on these cells is investigated in several in vivo and in vitro studies demonstrating differences in protein expression and signaling pathways. In summary, osteogenic marker changes indicate that cyclic tensile forces support whereas static tension inhibits cementogenesis. Furthermore, cementogenesis experiences the same protein expression changes in static conditions as static tension, but cyclic compression leads to the exact opposite of cyclic tension. Consistent with marker expression changes, the singaling pathways of Wnt/ß-catenin and RANKL/OPG show that tissue compression leads to cementum degradation and tension forces to cementogenesis. However, the cementum, and in particular its cementoblasts, remain a research area which should be explored in more detail to understand the underlying mechanism of bone resorption and remodeling after orthodontic treatments.}, language = {en} } @article{LenzKahmannBehbahanietal.2022, author = {Lenz, Maximilian and Kahmann, Stephanie Lucina and Behbahani, Mehdi and Pennig, Lenhard and Hackl, Michael and Leschinger, Tim and M{\"u}ller, Lars Peter and Wegmann, Kilian}, title = {Influence of rotator cuff preload on fracture configuration in proximal humerus fractures: a proof of concept for fracture simulation}, series = {Archives of Orthopaedic and Trauma Surgery}, journal = {Archives of Orthopaedic and Trauma Surgery}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {1434-3916}, doi = {10.1007/s00402-022-04471-9}, year = {2022}, abstract = {Introduction In regard of surgical training, the reproducible simulation of life-like proximal humerus fractures in human cadaveric specimens is desirable. The aim of the present study was to develop a technique that allows simulation of realistic proximal humerus fractures and to analyse the influence of rotator cuff preload on the generated lesions in regards of fracture configuration. Materials and methods Ten cadaveric specimens (6 left, 4 right) were fractured using a custom-made drop-test bench, in two groups. Five specimens were fractured without rotator cuff preload, while the other five were fractured with the tendons of the rotator cuff preloaded with 2 kg each. The humeral shaft and the shortened scapula were potted. The humerus was positioned at 90° of abduction and 10° of internal rotation to simulate a fall on the elevated arm. In two specimens of each group, the emergence of the fractures was documented with high-speed video imaging. Pre-fracture radiographs were taken to evaluate the deltoid-tuberosity index as a measure of bone density. Post-fracture X-rays and CT scans were performed to define the exact fracture configurations. Neer's classification was used to analyse the fractures. Results In all ten cadaveric specimens life-like proximal humerus fractures were achieved. Two III-part and three IV-part fractures resulted in each group. The preloading of the rotator cuff muscles had no further influence on the fracture configuration. High-speed videos of the fracture simulation revealed identical fracture mechanisms for both groups. We observed a two-step fracture mechanism, with initial impaction of the head segment against the glenoid followed by fracturing of the head and the tuberosities and then with further impaction of the shaft against the acromion, which lead to separation of the tuberosities. Conclusion A high energetic axial impulse can reliably induce realistic proximal humerus fractures in cadaveric specimens. The preload of the rotator cuff muscles had no influence on initial fracture configuration. Therefore, fracture simulation in the proximal humerus is less elaborate. Using the presented technique, pre-fractured specimens are available for real-life surgical education.}, language = {en} } @article{MalinowskiFournierHorbachetal.2022, author = {Malinowski, Daniel and Fournier, Yvan and Horbach, Andreas and Frick, Michael and Magliani, Mirko and Kalverkamp, Sebastian and Hildinger, Martin and Spillner, Jan and Behbahani, Mehdi and Hima, Flutura}, title = {Computational fluid dynamics analysis of endoluminal aortic perfusion}, series = {Perfusion}, volume = {0}, journal = {Perfusion}, number = {0}, publisher = {Sage}, address = {London}, issn = {1477-111X}, doi = {10.1177/02676591221099809}, pages = {1 -- 8}, year = {2022}, abstract = {Introduction: In peripheral percutaneous (VA) extracorporeal membrane oxygenation (ECMO) procedures the femoral arteries perfusion route has inherent disadvantages regarding poor upper body perfusion due to watershed. With the advent of new long flexible cannulas an advancement of the tip up to the ascending aorta has become feasible. To investigate the impact of such long endoluminal cannulas on upper body perfusion, a Computational Fluid Dynamics (CFD) study was performed considering different support levels and three cannula positions. Methods: An idealized literature-based- and a real patient proximal aortic geometry including an endoluminal cannula were constructed. The blood flow was considered continuous. Oxygen saturation was set to 80\% for the blood coming from the heart and to 100\% for the blood leaving the cannula. 50\% and 90\% venoarterial support levels from the total blood flow rate of 6 l/min were investigated for three different positions of the cannula in the aortic arch. Results: For both geometries, the placement of the cannula in the ascending aorta led to a superior oxygenation of all aortic blood vessels except for the left coronary artery. Cannula placements at the aortic arch and descending aorta could support supra-aortic arteries, but not the coronary arteries. All positions were able to support all branches with saturated blood at 90\% flow volume. Conclusions: In accordance with clinical observations CFD analysis reveals, that retrograde advancement of a long endoluminal cannula can considerably improve the oxygenation of the upper body and lead to oxygen saturation distributions similar to those of a central cannulation.}, language = {en} } @article{Fabo2022, author = {Fabo, Sabine}, title = {Das Parasit{\"a}re in der Pandemie}, series = {Parasite Art}, journal = {Parasite Art}, number = {Issue 2}, editor = {Wirth, Jacob}, publisher = {Parasite Art}, pages = {8 -- 11}, year = {2022}, language = {de} } @article{UlmerBraunChengetal.2022, author = {Ulmer, Jessica and Braun, Sebastian and Cheng, Chi-Tsun and Dowey, Steve and Wollert, J{\"o}rg}, title = {Gamification of virtual reality assembly training: Effects of a combined point and level system on motivation and training results}, series = {International Journal of Human-Computer Studies}, volume = {165}, journal = {International Journal of Human-Computer Studies}, number = {Art. No. 102854}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1071-5819}, doi = {10.1016/j.ijhcs.2022.102854}, year = {2022}, abstract = {Virtual Reality (VR) offers novel possibilities for remote training regardless of the availability of the actual equipment, the presence of specialists, and the training locations. Research shows that training environments that adapt to users' preferences and performance can promote more effective learning. However, the observed results can hardly be traced back to specific adaptive measures but the whole new training approach. This study analyzes the effects of a combined point and leveling VR-based gamification system on assembly training targeting specific training outcomes and users' motivations. The Gamified-VR-Group with 26 subjects received the gamified training, and the Non-Gamified-VR-Group with 27 subjects received the alternative without gamified elements. Both groups conducted their VR training at least three times before assembling the actual structure. The study found that a level system that gradually increases the difficulty and error probability in VR can significantly lower real-world error rates, self-corrections, and support usages. According to our study, a high error occurrence at the highest training level reduced the Gamified-VR-Group's feeling of competence compared to the Non-Gamified-VR-Group, but at the same time also led to lower error probabilities in real-life. It is concluded that a level system with a variable task difficulty should be combined with carefully balanced positive and negative feedback messages. This way, better learning results, and an improved self-evaluation can be achieved while not causing significant impacts on the participants' feeling of competence.}, language = {en} } @article{Dachwald2005, author = {Dachwald, Bernd}, title = {Optimization of very-low-thrust trajectories using evolutionary neurocontrol}, series = {Acta Astronautica}, volume = {57}, journal = {Acta Astronautica}, number = {2-8}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, isbn = {1879-2030}, pages = {175 -- 185}, year = {2005}, abstract = {Searching optimal interplanetary trajectories for low-thrust spacecraft is usually a difficult and time-consuming task that involves much experience and expert knowledge in astrodynamics and optimal control theory. This is because the convergence behavior of traditional local optimizers, which are based on numerical optimal control methods, depends on an adequate initial guess, which is often hard to find, especially for very-low-thrust trajectories that necessitate many revolutions around the sun. The obtained solutions are typically close to the initial guess that is rarely close to the (unknown) global optimum. Within this paper, trajectory optimization problems are attacked from the perspective of artificial intelligence and machine learning. Inspired by natural archetypes, a smart global method for low-thrust trajectory optimization is proposed that fuses artificial neural networks and evolutionary algorithms into so-called evolutionary neurocontrollers. This novel method runs without an initial guess and does not require the attendance of an expert in astrodynamics and optimal control theory. This paper details how evolutionary neurocontrol works and how it could be implemented. The performance of the method is assessed for three different interplanetary missions with a thrust to mass ratio <0.15mN/kg (solar sail and nuclear electric).}, language = {en} } @article{LoebSchartnerDachwaldetal.2012, author = {Loeb, Horst Wolfgang and Schartner, Karl-Heinz and Dachwald, Bernd and Ohndorf, Andreas and Seboldt, Wolfgang}, title = {Interstellar heliopause probe}, series = {Труды МАИ}, journal = {Труды МАИ}, number = {60}, publisher = {Moskauer Staatliches Luftfahrtinstitut (МАИ)}, address = {Moskau}, pages = {2 -- 2}, year = {2012}, abstract = {There is common agreement within the scientific community that in order to understand our local galactic environment it will be necessary to send a spacecraft into the region beyond the solar wind termination shock. Considering distances of 200 AU for a new mission, one needs a spacecraft traveling at a speed of close to 10 AU/yr in order to keep the mission duration in the range of less than 25 yrs, a transfer time postulated by European Space Agency (ESA). Two propulsion options for the mission have been proposed and discussed so far: the solar sail propulsion and the ballistic/radioisotope-electric propulsion (REP). As a further alternative, we here investigate a combination of solar-electric propulsion (SEP) and REP. The SEP stage consists of six 22-cms diameter RIT-22 ion thrusters working with a high specific impulse of 7377 s corresponding to a positive grid voltage of 5 kV. Solar power of 53 kW at begin of mission (BOM) is provided by a lightweight solar array.}, language = {en} } @article{ValeroBungErpicumetal.2022, author = {Valero, Daniel and Bung, Daniel B. and Erpicum, Sebastien and Peltier, Yann and Dewals, Benjamin}, title = {Unsteady shallow meandering flows in rectangular reservoirs: a modal analysis of URANS modelling}, series = {Journal of Hydro-environment Research}, journal = {Journal of Hydro-environment Research}, number = {In Press}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1570-6443}, doi = {10.1016/j.jher.2022.03.002}, year = {2022}, abstract = {Shallow flows are common in natural and human-made environments. Even for simple rectangular shallow reservoirs, recent laboratory experiments show that the developing flow fields are particularly complex, involving large-scale turbulent structures. For specific combinations of reservoir size and hydraulic conditions, a meandering jet can be observed. While some aspects of this pseudo-2D flow pattern can be reproduced using a 2D numerical model, new 3D simulations, based on the unsteady Reynolds-Averaged Navier-Stokes equations, show consistent advantages as presented herein. A Proper Orthogonal Decomposition was used to characterize the four most energetic modes of the meandering jet at the free surface level, allowing comparison against experimental data and 2D (depth-averaged) numerical results. Three different isotropic eddy viscosity models (RNG k-ε, k-ε, k-ω) were tested. The 3D models accurately predicted the frequency of the modes, whereas the amplitudes of the modes and associated energy were damped for the friction-dominant cases and augmented for non-frictional ones. The performance of the three turbulence models remained essentially similar, with slightly better predictions by RNG k-ε model in the case with the highest Reynolds number. Finally, the Q-criterion was used to identify vortices and study their dynamics, assisting on the identification of the differences between: i) the three-dimensional phenomenon (here reproduced), ii) its two-dimensional footprint in the free surface (experimental observations) and iii) the depth-averaged case (represented by 2D models).}, language = {en} } @article{BhattaraiHorbachStaatetal.2022, author = {Bhattarai, Aroj and Horbach, Andreas and Staat, Manfred and Kowalczyk, Wojciech and Tran, Thanh Ngoc}, title = {Virgin passive colon biomechanics and a literature review of active contraction constitutive models}, series = {Biomechanics}, volume = {2}, journal = {Biomechanics}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2673-7078}, doi = {10.3390/biomechanics2020013}, pages = {138 -- 157}, year = {2022}, abstract = {The objective of this paper is to present our findings on the biomechanical aspects of the virgin passive anisotropic hyperelasticity of the porcine colon based on equibiaxial tensile experiments. Firstly, the characterization of the intestine tissues is discussed for a nearly incompressible hyperelastic fiber-reinforced Holzapfel-Gasser-Ogden constitutive model in virgin passive loading conditions. The stability of the evaluated material parameters is checked for the polyconvexity of the adopted strain energy function using positive eigenvalue constraints of the Hessian matrix with MATLAB. The constitutive material description of the intestine with two collagen fibers in the submucosal and muscular layer each has been implemented in the FORTRAN platform of the commercial finite element software LS-DYNA, and two equibiaxial tensile simulations are presented to validate the results with the optical strain images obtained from the experiments. Furthermore, this paper also reviews the existing models of the active smooth muscle cells, but these models have not been computationally studied here. The review part shows that the constitutive models originally developed for the active contraction of skeletal muscle based on Hill's three-element model, Murphy's four-state cross-bridge chemical kinetic model and Huxley's sliding-filament hypothesis, which are mainly used for arteries, are appropriate for numerical contraction numerical analysis of the large intestine.}, language = {en} } @article{GollandEngling2014, author = {Golland, Alexander and Engling, Christoph}, title = {a-i3/BSI Symposium 2014: Sicherheit von Daten und Identit{\"a}ten angesichts NSA und Big Data}, series = {DSB Datenschutz-Berater}, volume = {38}, journal = {DSB Datenschutz-Berater}, number = {7-8}, publisher = {dfv Mediengruppe}, address = {Frankfurt a.M.}, isbn = {0170-7256}, pages = {165 -- 166}, year = {2014}, language = {de} } @article{PeloniCeriottiDachwald2016, author = {Peloni, Alessandro and Ceriotti, Matteo and Dachwald, Bernd}, title = {Solar-sail trajectory design for a multiple near-earth-asteroid rendezvous mission}, series = {Journal of Guidance, Control, and Dynamics}, volume = {39}, journal = {Journal of Guidance, Control, and Dynamics}, number = {12}, publisher = {AIAA}, address = {Reston, Va.}, issn = {0731-5090}, doi = {10.2514/1.G000470}, pages = {2712 -- 2724}, year = {2016}, abstract = {The scientific interest for near-Earth asteroids as well as the interest in potentially hazardous asteroids from the perspective of planetary defense led the space community to focus on near-Earth asteroid mission studies. A multiple near-Earth asteroid rendezvous mission with close-up observations of several objects can help to improve the characterization of these asteroids. This work explores the design of a solar-sail spacecraft for such a mission, focusing on the search of possible sequences of encounters and the trajectory optimization. This is done in two sequential steps: a sequence search by means of a simplified trajectory model and a set of heuristic rules based on astrodynamics, and a subsequent optimization phase. A shape-based approach for solar sailing has been developed and is used for the first phase. The effectiveness of the proposed approach is demonstrated through a fully optimized multiple near-Earth asteroid rendezvous mission. The results show that it is possible to visit five near-Earth asteroids within 10 years with near-term solar-sail technology.}, language = {en} } @article{Golland2014, author = {Golland, Alexander}, title = {Datenschutz durch modulare Zertifizierung: Trusted Cloud-Pilotprojekt bringt neuen Ansatz}, series = {DSB Datenschutz-Berater}, volume = {38}, journal = {DSB Datenschutz-Berater}, number = {10}, publisher = {dfv Mediengruppe}, address = {Frankfurt a.M.}, isbn = {0170-7256}, pages = {213 -- 215}, year = {2014}, language = {de} } @article{GollandEngling2015, author = {Golland, Alexander and Engling, Christoph}, title = {Offene und geschlossene WLAN: Rechtliche H{\"u}rden bei Betrieb eines {\"o}ffentlichen Internetzugangs}, series = {DSB Datenschutz-Berater}, volume = {39}, journal = {DSB Datenschutz-Berater}, number = {5}, publisher = {Beck}, address = {G{\"u}tersloh}, issn = {0170-7256}, pages = {102 -- 103}, year = {2015}, language = {de} } @article{GollandKriegesmann2017, author = {Golland, Alexander and Kriegesmann, Torben}, title = {Der Schutz virtueller Identit{\"a}ten durch die DSGVO}, series = {PinG Privacy in Germany}, volume = {5}, journal = {PinG Privacy in Germany}, number = {2}, editor = {H{\"a}rting, Niko}, publisher = {Erich Schmidt Verlag}, address = {Berlin}, isbn = {2197-1862}, doi = {10.37307/j.2196-9817.2017.02.03}, pages = {45 -- 50}, year = {2017}, abstract = {Die Frage des Schutzes von virtuellen Identit{\"a}ten ist - insbesondere bei Online-Medien - von elementarer Bedeutung: Ihre Beantwortung entscheidet {\"u}ber die Anwendbarkeit des Datenschutzrechts auf vermeintlich anonyme Nutzerprofile im Internet. Eine differenzierte Auseinandersetzung mit der Problematik, ob und unter welchen Umst{\"a}nden virtuelle Identit{\"a}ten dem Datenschutzrecht unterfallen, fehlt bislang. Der vorliegende Beitrag gibt einen {\"U}berblick {\"u}ber den Schutz virtueller Identit{\"a}ten und zeigt Ans{\"a}tze auf, mittels derer bestimmt werden kann, wann virtuelle Identit{\"a}ten nach Inkrafttreten der DSGVO durch das Datenschutzrecht gesch{\"u}tzt werden.}, language = {de} } @article{Golland2018, author = {Golland, Alexander}, title = {Umsetzung der Datenschutz-Grundverordnung - Neue Herausforderungen f{\"u}r Unternehmen}, series = {NWB Rechnungswesen - BBK}, journal = {NWB Rechnungswesen - BBK}, number = {1}, isbn = {0340-9848}, pages = {35 -- 39}, year = {2018}, abstract = {Nach einem intensiven politischen Diskurs wurde im vergangenen Jahr die Datenschutz-Grundverordnung (DSGVO) verabschiedet. Die DSGVO ersetzt zum 25.5.2018 die bislang geltende, aus dem Jahre 1995 stammende Datenschutz-Richtlinie 95/46/EG. Die Novellierung des Datenschutzrechts bringt zahlreiche neue Anforderungen mit sich. Unternehmen sind daher gezwungen, sich auf die {\"A}nderungen einzustellen, ihre datenschutzrelevanten Prozesse im Hinblick auf die neuen Anforderungen zu {\"u}berpr{\"u}fen und bis zum Mai 2018 an der DSGVO auszurichten. Der Beitrag gibt einen kurzen {\"U}berblick {\"u}ber die zentralen Aspekte der Datenschutzreform und die damit einhergehenden Herausforderungen f{\"u}r Unternehmen.}, language = {de} } @article{Golland2018, author = {Golland, Alexander}, title = {Das Kopplungsverbot in der Datenschutz-Grundverordnung Anwendungsbereich, {\"o}konomische Auswirkungen auf Web 2.0-Dienste und L{\"o}sungsvorschlag}, series = {MMR Multimedia und Recht}, volume = {21}, journal = {MMR Multimedia und Recht}, number = {3}, publisher = {Beck}, address = {M{\"u}nchen}, isbn = {1434-596X}, pages = {130 -- 135}, year = {2018}, abstract = {Das Kopplungsverbot fristete - obwohl in rechtswissenschaftlicher Literatur seit jeher diskutiert - unter der Geltung des BDSG ein Schattendasein. Mit der Datenschutz-Grundverordnung (DS-GVO) ist eine {\"A}nderung absehbar: Der neue Art. EWG_DSGVO Artikel 7 Abs. EWG_DSGVO Artikel 7 Absatz 4 DS-GVO stellt klar, dass die Leistungserbringung nicht von der Einwilligungserteilung abh{\"a}ngig gemacht werden darf. Doch dieses scheinbare Novum des Datenschutzrechts wirft zahlreiche Fragen auf. W{\"a}hrend vor allem Vertreter der unternehmerischen Praxis die Anwendung des Kopplungsverbots in zahlreichen Konstellationen ablehnen, beschw{\"o}ren dessen Apologeten das Ende s{\"a}mtlicher „datenfinanzierten" Dienste herauf. Der vorliegende Beitrag gibt Einblick in die Regelungstiefe einer Norm, die das Web 2.0 revolutionieren k{\"o}nnte, und schl{\"a}gt eine L{\"o}sung vor, die dem Schutz der Privatsph{\"a}re des Betroffenen und den wirtschaftlichen Interessen von Diensteanbietern gleichermaßen gerecht wird.}, language = {de} } @article{Golland2018, author = {Golland, Alexander}, title = {Der r{\"a}umliche Anwendungsbereich der DS-GVO}, series = {DuD Datenschutz und Datensicherheit}, volume = {42}, journal = {DuD Datenschutz und Datensicherheit}, number = {6}, publisher = {Springer}, address = {Heidelberg}, isbn = {1862-2607}, pages = {351 -- 357}, year = {2018}, abstract = {Die Datenschutz-Grundverordnung (DS-GVO) regelt in ihrem Art. 3 das r{\"a}umlich anwendbare Datenschutzrecht und zielt dabei gerade auch auf Angebote nichteurop{\"a}ischer Diensteanbieter ab. Die bisherige Diskussion konzentriert sich bislang in erster Linie darauf, das eingef{\"u}hrte Marktortprinzip zu thematisieren; das weitgehend unangetastete Niederlassungsprinzip und vor allem die Probleme, die sich durch dessen unver{\"a}nderte Beibehaltung ergeben, werden dagegen nicht er{\"o}rtert. Der folgende Beitrag versucht sich an einer systematischen Analyse eines teils kontrovers, teils kaum diskutierten Themas.}, language = {de} } @article{Golland2018, author = {Golland, Alexander}, title = {Gemeinsame Verantwortlichkeit in mehrstufigen Verarbeitungsszenarien}, volume = {21}, number = {7-8}, publisher = {dfv Mediengruppe}, address = {Frankfurt a.M.}, issn = {1434-6354}, pages = {433 -- 438}, year = {2018}, abstract = {Die Rechtsfigur der gemeinsamen Verantwortlichkeit besch{\"a}ftigt die datenschutzrechtliche Literatur seit Langem. Die Bestimmung der Verantwortlichkeit bei arbeitsteiligen Verarbeitungsverfahren, welche vor allem bei heutigen Plattformdiensten {\"u}blich sind, ist komplex: Stets sind mehrere Akteure beteiligt und in der Regel werden durch die Handlung eines Beteiligten mehrere Verarbeitungsschritte ausgel{\"o}st. Nun hat sich der EuGH in einem in mehrfacher Hinsicht bemerkenswerten Urteil ge{\"a}ußert.}, language = {de} } @article{Golland2018, author = {Golland, Alexander}, title = {Das neue kirchliche Datenschutzrecht - Herausforderungen f{\"u}r Unternehmen der Privatwirtschaft}, series = {DSB Datenschutz-Berater}, volume = {42}, journal = {DSB Datenschutz-Berater}, number = {9}, publisher = {dfv Mediengruppe}, address = {Frankfurt a.M.}, isbn = {0170-7256}, pages = {179 -- 181}, year = {2018}, language = {de} }