TY - GEN AU - N., N. ID - 45239 TI - Lightweight Process Engine for Situation-specific Development of Business Models for Digital Platforms ER - TY - GEN AU - N., N. ID - 45240 TI - Development and Evaluation of a Multi Platform Approach for Augmented Reality Product Configuration ER - TY - GEN AU - N., N. ID - 45238 TI - Model-based Feature Backlog Synchronization for Dual-Track Development Methods ER - TY - JOUR AB - Heat-assisted forming processes are becoming increasingly important in the manufacturing of sheet metal parts for body-in-white applications. However, the non-isothermal nature of these processes leads to challenges in evaluating the forming limits, since established methods such as Forming Limit Curves (FLCs) only allow the assessment of critical forming strains for steady temperatures. For this reason, a temperature-dependent extension of the well-established GISSMO (Generalized Incremental Stress State Dependent Damage Model) fracture indicator framework is developed by the authors to predict forming failures under non-isothermal conditions. In this paper, a general approach to combine several isothermal FLCs within the temperature-extended GISSMO model into a temperature-dependent forming limit surface is investigated. The general capabilities of the model are tested in a coupled thermo-mechanical FEA using the example of warm forming of an AA5182-O sheet metal cross-die cup. The obtained results are then compared with state of the art of evaluation methods. By taking the strain and temperature path into account, GISSMO predicts greater drawing depths by up to 20% than established methods. In this way the forming and so the lightweight potential of sheet metal parts can by fully exploited. Moreover, the risk and locus of failure can be evaluated directly on the part geometry by a contour plot. An additional advantage of the GISSMO model is the applicability for low triaxialities as well as the possibility to predict the materials behavior beyond necking up to ductile fracture. AU - Camberg, Alan Adam AU - Erhart, Tobias AU - Tröster, Thomas ID - 24009 JF - Materials SN - 1996-1944 TI - A Generalized Stress State and Temperature Dependent Damage Indicator Framework for Ductile Failure Prediction in Heat-Assisted Forming Operations ER - TY - GEN AU - Anonymous, Anonymous ID - 45254 TI - Device-Independent Security Proofs Via Entropy Accumulation ER - TY - CHAP AU - Saad, Nadia ID - 42253 T2 - Methoden der Darstellung und Analyse interreligiöser Diskurse TI - David und Salomo im Koran: ein Komparativ-theologischer Ansatz VL - 1 ER - TY - JOUR AU - Mir Sadri, Seyedeh Saeideh AU - Nasiri, Mansour ID - 42256 IS - 2 JF - Philosophy East and West TI - Reading Iqbal in the Light of Kierkegaard; towards an Existentialist Approach to Islam VL - 71 ER - TY - JOUR AU - Mir Sadri, Seyedeh Saeideh ID - 42257 IS - 1 JF - Amos-international TI - Fratelli e sorelle tutti. Die Sozialenzyklika aus islamischer Sicht VL - 15 ER - TY - CHAP AU - Eikermann, Larissa ED - Ströter-Bender, Jutta ID - 45275 SN - 9783828876668 T2 - Das Erbe der Kinder: Provenienzforschung und Sammlungsgeschichte von Kinder- und Jugendzeichnungen: Museen, Archive, private Kollektionen und "verschwundene Sammlungen" = The children's heritage: provenance research and the history of children's and youth drawings collections: museums, archives, private holdings and "lost collections" TI - "Ein altes Familientalent" - Kinderzeichnungen aus der Familie der Brüder Grimm (1. Hälfte 19. Jh.) in der Grimm-Sammlung der Stadt Kassel. Germany VL - Bd. 30 ER - TY - CHAP AU - Eikermann, Larissa ED - Ströter-Bender, Jutta ID - 45276 SN - 9783828876668 T2 - Das Erbe der Kinder: Provenienzforschung und Sammlungsgeschichte von Kinder- und Jugendzeichnungen: Museen, Archive, private Kollektionen und "verschwundene Sammlungen" = The children's heritage: provenance research and the history of children's and youth drawings collections: museums, archives, private holdings and "lost collections" TI - Children´s drawings on Pippi & Co. - A visit to the Astrid Lindgren Archive in the Royal Library of Stockholm. Sweden VL - Bd. 30 ER - TY - CHAP AU - Kamcili-Yildiz, Naciye ED - Espelage, Christian ED - Mohagheghi, Hamideh ED - Schober, Michael ID - 42096 T2 - Interreligiöse Öffnung durch Begegnung. Grundlagen - Erfahrungen - Perspektiven im Kontext des christlich-islamischen Dialogs TI - Begegnungslernen in den Kerncurricula des islamischen Religionsunterrichts VL - 43 ER - TY - BOOK AU - Kamcili-Yildiz, Naciye ID - 42058 SN - 973-3830942958 TI - Zwischen Glaubensvermittlung und Reflexivität: Eine quantitative Studie zu professionellen Kompetenzen von islamischen ReligionslehrerInnen VL - 682 ER - TY - JOUR AU - Mustafa, Abdul Rahman ID - 42265 IS - 8 JF - Political Theology TI - Supernatural, Unnatural, Queer: Gratitude and Nature in Islamic Political Theology VL - 22 ER - TY - JOUR AU - Aghaei Abrandabadi, Seyed Ali AU - Marx, Michel ID - 42224 IS - 1 JF - Journal of Iranian National Museum TI - Carbon Dating of Seven Parchment Qurʾān Manuscripts and One Syriac Bible of the National Museum of Iran VL - 2 ER - TY - JOUR AU - Ghaffar, Zishan ID - 42341 IS - 2 JF - Der Islam TI - Kontrafaktische Intertextualität im Koran und die exegetische Tradition des syrischen Christentums VL - 98 ER - TY - CHAP AU - Tatari, Muna ED - Khalfaoui, Mouez ED - Ehret, Jean ID - 37120 SN - 9783451391439 T2 - Islamische Theologie in Deutschland. Ein Modell für Europa und die Welt TI - Islamische systematische Theologie in Deutschland: Konturen eines jungen Faches ER - TY - BOOK AU - Tatari, Muna AU - von Stosch, Klaus ID - 37035 SN - 3451389649 TI - Prophetin - Jungfrau - Mutter: Maria im Koran ER - TY - GEN AU - Nassery, Idris ID - 42479 T2 - Frankfurter Allgemeine Zeitung TI - Die unerwünschte Empfehlung, Hybris: Woran der Westen in Afghanistan tatsächlich gescheitert ist ER - TY - JOUR AU - Kulgemeyer, Christoph AU - Kempin, Maren AU - Weißbach, Anna AU - Borowski, Andreas AU - Buschhüter, David AU - Enkrott, Patrick AU - Reinhold, Peter AU - Riese, Josef AU - Schecker, Horst AU - Schröder, Jan AU - Vogelsang, Christoph ID - 45177 IS - 18 JF - International Journal of Science Education KW - Education SN - 0950-0693 TI - Exploring the impact of pre-service science teachers’ reflection skills on the development of professional knowledge during a field experience VL - 43 ER - TY - CONF AU - Große-Heilmann, Rike Isabel AU - Burde, Jan-Philipp AU - Riese, Josef AU - Schubatzky, Thomas AU - Weiler, David ID - 45407 T2 - PhyDid B-Didaktik der Physik-Beiträge zur DPG-Frühjahrstagung 2021 TI - Erwerb und Messung physikdidaktischer Kompetenzen zum Einsatz digitaler Medien ER - TY - CONF AU - Weiler, David AU - Burde, Jan-Philipp AU - Große-Heilmann, Rike Isabel AU - Lachner, Andreas AU - Riese, Josef AU - Schubatzky, Thomas ID - 45408 T2 - PhyDid B-Didaktik der Physik-Beiträge zur DPG-Frühjahrstagung 2021 TI - Entwicklung eines Seminars zur Förderung des Konzeptverständnisses mittels digitaler Medien ER - TY - CHAP AU - Haghani Fazl, Mohammad ED - Grössl, Johannes ED - von Stosch, Klaus ID - 45436 T2 - Impeccability and Temptation: Understanding Christ's Divine and Human Will TI - The Scope of ‘iṣma and Qur’anic Evidence ER - TY - JOUR AU - Hein, Maxwell AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 41511 IS - 7 JF - Materialwissenschaft und Werkstofftechnik KW - Mechanical Engineering KW - Mechanics of Materials KW - Condensed Matter Physics KW - General Materials Science SN - 0933-5137 TI - Additively processed TiAl6Nb7 alloy for biomedical applications VL - 52 ER - TY - JOUR AB - Purpose The currently existing restrictions regarding the deployment of additively manufactured components because of poor surface roughness, porosity and residual stresses as well as their influence on the low-cycle fatigue (LCF) strength are addressed in this paper. Design/methodology/approach This study aims to evaluating the effect of different pre- and post-treatments on the LCF strength of additively manufactured 316L parts. Therefore, 316L specimens manufactured by laser powder bed fusion were examined in their as-built state as well as after grinding, or coating with regard to the surface roughness, residual stresses and LCF strength. To differentiate between topographical effects and residual stress-related phenomena, stress-relieved 316L specimens served as a reference throughout the investigations. To enable an alumina coating of the 316L components, atmospheric plasma spraying was used, and the near-surface residual stresses and the surface roughness are measured and investigated. Findings The results have shown that the applied pre- and post-treatments such as stress-relief heat treatment, grinding and alumina coating have each led to an increase in LCF strength of the 316L specimens. In contrast, the non-heat-treated specimens predominantly exhibited coating delamination. Originality/value To the best of the authors’ knowledge, this is the first study of the correlation between the LCF behavior of additively manufactured uncoated 316L specimens in comparison with additively manufactured 316L specimens with an alumina coating. AU - Garthe, Kai-Uwe AU - Hoyer, Kay-Peter AU - Hagen, Leif AU - Tillmann, Wolfgang AU - Schaper, Mirko ID - 41507 IS - 5 JF - Rapid Prototyping Journal KW - Industrial and Manufacturing Engineering KW - Mechanical Engineering SN - 1355-2546 TI - Correlation between pre- and post-treatments of additively manufactured 316L parts and the resulting low cycle fatigue behavior VL - 28 ER - TY - JOUR AB - Processing aluminum alloys employing powder bed fusion of metals (PBF-LB/M) is becoming more attractive for the industry, especially if lightweight applications are needed. Unfortunately, high-strength aluminum alloys such as AA7075 are prone to hot cracking during PBF-LB/M, as well as welding. Both a large solidification range promoted by the alloying elements zinc and copper and a high thermal gradient accompanied with the manufacturing process conditions lead to or favor hot cracking. In the present study, a simple method for modifying the powder surface with titanium carbide nanoparticles (NPs) as a nucleating agent is aimed. The effect on the microstructure with different amounts of the nucleating agent is shown. For the aluminum alloy 7075 with 2.5 ma% titanium carbide nanoparticles, manufactured via PBF-LB/M, crack-free samples with a refined microstructure having no discernible melt pool boundaries and columnar grains are observed. After using a two-step ageing heat treatment, ultimate tensile strengths up to 465 MPa and an 8.9% elongation at break are achieved. Furthermore, it is demonstrated that not all nanoparticles used remain in the melt pool during PBF-LB/M. AU - Heiland, Steffen AU - Milkereit, Benjamin AU - Hoyer, Kay-Peter AU - Zhuravlev, Evgeny AU - Kessler, Olaf AU - Schaper, Mirko ID - 41506 IS - 23 JF - Materials KW - General Materials Science SN - 1996-1944 TI - Requirements for Processing High-Strength AlZnMgCu Alloys with PBF-LB/M to Achieve Crack-Free and Dense Parts VL - 14 ER - TY - JOUR AB - Implants often overtake body function just for a certain time and remain as an unnecessary foreign body or have to be removed. Thus, resorbable implants are highly beneficial to reduce patient burden. Besides established materials, Iron-(Fe)-based alloys are in focus due to superior mechanical properties and good biocompatibility. However, their degradation rate needs to be increased. Phases with high electrochemical potential could promote the dissolution of residual material based on the galvanic coupling. Silver (Ag) is promising due to its high electrochemical potential (+0.8 V vs. SHE), immiscibility with Fe, biocompatibility, and anti-bacterial properties. But to prevent adverse consequences the Ag-particles, remaining after dissolution of the matrix, need to dissolve. Thus, a bioresorbable Ag-alloy is required. Regarding the electrochemical potential and degradation behavior of binary alloys, Cerium (Ce) and Lanthanum (La) are well-suited considering their biocompatibility and antibacterial behavior. Accordingly, this research addresses AgCe and AgCeLa alloys as additives for Fe-based materials with adapted degradation behavior. Furthermore, degradable Ag-alloys combined with inert implant materials could enable the controlled release of antibacterial active Ag-ions. AU - Krüger, Jan Tobias AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 24790 JF - Materials Letters SN - 0167-577X TI - Bioresorbable AgCe and AgCeLa alloys for adapted Fe-based implants VL - 306 ER - TY - JOUR AU - Tillmann, Wolfgang AU - Lopes Dias, Nelson Filipe AU - Franke, Carlo AU - Kokalj, David AU - Stangier, Dominic AU - Filor, Viviane AU - Mateus-Vargas, Rafael Hernán AU - Oltmanns, Hilke AU - Kietzmann, Manfred AU - Meißner, Jessica AU - Hein, Maxwell AU - Pramanik, Sudipta AU - Hoyer, Kay-Peter AU - Schaper, Mirko AU - Nienhaus, Alexander AU - Thomann, Carl Arne AU - Debus, Jörg ID - 41516 JF - Surface and Coatings Technology KW - Materials Chemistry KW - Surfaces KW - Coatings and Films KW - Surfaces and Interfaces KW - Condensed Matter Physics KW - General Chemistry SN - 0257-8972 TI - Tribo-mechanical properties and biocompatibility of Ag-containing amorphous carbon films deposited onto Ti6Al4V VL - 421 ER - TY - JOUR AU - Andreiev, Anatolii AU - Hoyer, Kay-Peter AU - Dula, Dimitri AU - Hengsbach, Florian AU - Grydin, Olexandr AU - Frolov, Yaroslav AU - Schaper, Mirko ID - 41512 JF - Materials Science and Engineering: A KW - Mechanical Engineering KW - Mechanics of Materials KW - Condensed Matter Physics KW - General Materials Science SN - 0921-5093 TI - Laser beam melting of functionally graded materials with application-adapted tailoring of magnetic and mechanical performance VL - 822 ER - TY - JOUR AU - Pramanik, Sudipta AU - Andreiev, Anatolii AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 41510 JF - International Journal of Fatigue KW - Industrial and Manufacturing Engineering KW - Mechanical Engineering KW - Mechanics of Materials KW - General Materials Science KW - Modeling and Simulation SN - 0142-1123 TI - Quasi in-situ analysis of fracture path during cyclic loading of double-edged U notched additively manufactured FeCo alloy VL - 153 ER - TY - JOUR AU - Krüger, Jan Tobias AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 41509 JF - Materials Letters KW - Mechanical Engineering KW - Mechanics of Materials KW - Condensed Matter Physics KW - General Materials Science SN - 0167-577X TI - Bioresorbable AgCe and AgCeLa alloys for adapted Fe-based implants VL - 306 ER - TY - JOUR AU - Andreiev, Anatolii AU - Hoyer, Kay-Peter AU - Dula, Dimitri AU - Hengsbach, Florian AU - Haase, Michael AU - Gierse, Jan AU - Zimmer, Detmar AU - Tröster, Thomas AU - Schaper, Mirko ID - 23898 JF - Journal of Materials Processing Technology SN - 0924-0136 TI - Soft-magnetic behavior of laser beam melted FeSi3 alloy with graded cross-section ER - TY - JOUR AB - AbstractWithin this research, the multiscale microstructural evolution before and after the tensile test of a FeCo alloy is addressed. X-ray µ-computer tomography (CT), electron backscattered diffraction (EBSD), and transmission electron microscopy (TEM) are employed to determine the microstructure on different length scales. Microstructural evolution is studied by performing EBSD of the same area before and after the tensile test. As a result, $$\langle$$ 001$$\rangle$$ ||TD, $$\langle$$ 011$$\rangle$$ ||TD are hard orientations and $$\langle$$ 111$$\rangle$$ ||TD is soft orientations for deformation accommodation. It is not possible to predict the deformation of a single grain with the Taylor model. However, the Taylor model accurately predicts the orientation of all grains after deformation. {123}$$\langle$$ 111$$\rangle$$ is the most active slip system, and {112}$$\langle$$ 111$$\rangle$$ is the least active slip system. Both EBSD micrographs show grain subdivision after tensile testing. TEM images show the formation of dislocation cells. Correlative HRTEM images show unresolved lattice fringes at dislocation cell boundaries, whereas resolved lattice fringes are observed at dislocation cell interior. Since Schmid’s law is unable to predict the deformation behavior of grains, the boundary slip transmission accurately predicts the grain deformation behavior. AU - Pramanik, Sudipta AU - Tasche, Lennart AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 41517 IS - 11 JF - Journal of Materials Engineering and Performance KW - Mechanical Engineering KW - Mechanics of Materials KW - General Materials Science SN - 1059-9495 TI - Correlation between Taylor Model Prediction and Transmission Electron Microscopy-Based Microstructural Investigations of Quasi-In Situ Tensile Deformation of Additively Manufactured FeCo Alloy VL - 30 ER - TY - JOUR AB - The addition of Ag to amorphous carbon (a-C) films is highly effective in tailoring the tribo-mechanical properties and biocompatibility. For biomedical applications, Ag-containing a-C (a-C:Ag) represents a promising film material for improving the biofunctional surface properties of Ti-based alloys. In a sputtering process, a-C:Ag films, with Ag contents up to 7.5 at.%, were deposited with a chemically graded TixCy interlayer onto Ti6Al4V. The tribo-mechanical and biocompatible properties of a-C:Ag were evaluated. The influence of the Ag content on these properties was analyzed and compared to those of uncoated Ti6Al4V. Raman spectroscopy reveals that the amount of incorporated Ag does not induce significant structural changes in the disordered network, only a reduced number of vacancies and sp3-coordinated C bonds within the sp2-dominant a-C network is assigned to the films with high Ag concentration. With increasing Ag content, stresses, hardness, and elastic modulus decrease from (2.02 ± 0.07) to (1.15 ± 0.03) GPa, from (17.4 ± 1.5) to (13.4 ± 0.9) GPa, and from (171.8 ± 8.1) to (138.5 ± 5.8) GPa, respectively. In tribometer tests, the friction behavior against Al2O3 in lubricated condition with a simulated-body-fluid-based lubricant is not affected by the Ag concentration, but the Al2O3 counterpart wear is reduced for all a-C:Ag films compared to a-C. The friction against ultra-high-molecular-weight polyethylene (UHMWPE) decreases continuously with increasing Ag concentration and the counterpart wear is lower at higher Ag contents. Compared to a-C:Ag, Ti6Al4V demonstrates lower friction against UHMWPE and higher friction against Al2O3. The a-C:Ag films are not exposed to abrasion by Al2O3 or pronounced material transfer of UHMWPE. The hardness difference and chemical affinity between the friction partners are decisive for the tribological behavior of a-C:Ag. Compared to Ti6Al4V, the a-C:Ag films show antibacterial activity against Staphylococcus aureus, while the proliferation of osteoblast-like cells is reduced by Ag. AU - Tillmann, Wolfgang AU - Lopes Dias, Nelson Filipe AU - Franke, Carlo AU - Kokalj, David AU - Stangier, Dominic AU - Filor, Viviane AU - Mateus-Vargas, Rafael Hernán AU - Oltmanns, Hilke AU - Kietzmann, Manfred AU - Meißner, Jessica AU - Hein, Maxwell AU - Pramanik, Sudipta AU - Hoyer, Kay-Peter AU - Schaper, Mirko AU - Nienhaus, Alexander AU - Thomann, Carl Arne AU - Debus, Jörg ID - 24243 JF - Surface and Coatings Technology SN - 0257-8972 TI - Tribo-mechanical properties and biocompatibility of Ag-containing amorphous carbon films deposited onto Ti6Al4V ER - TY - JOUR AB - Aluminium steel clad materials have high potential for industrial applications. Their mechanical properties are governed by an intermetallic layer, which forms upon heat treatment at the Al-Fe interface. Transmission electron microscopy was employed to identify the phases present at the interface by selective area electron diffraction and energy dispersive spectroscopy. Three phases were identified: orthorhombic Al5Fe2, monoclinic Al13Fe4 and cubic Al19Fe4MnSi2. An effective interdiffusion coefficient dependent on concentration was determined according to the Boltzmann–Matano method. The highest value of the interdiffusion coefficient was reached at the composition of the intermetallic phases. Afterwards, the process of diffusion considering the evaluated interdiffusion coefficient was simulated using the finite element method. Results of the simulations revealed that growth of the intermetallic phases proceeds preferentially in the direction of aluminium. AU - Křivská, Barbora AU - Šlapáková, Michaela AU - Veselý, Jozef AU - Kihoulou, Martin AU - Fekete, Klaudia AU - Minárik, Peter AU - Králík, Rostislav AU - Grydin, Olexandr AU - Stolbchenko, Mykhailo AU - Schaper, Mirko ID - 29815 IS - 24 JF - Materials KW - General Materials Science SN - 1996-1944 TI - Intermetallic Phases Identification and Diffusion Simulation in Twin-Roll Cast Al-Fe Clad Sheet VL - 14 ER - TY - JOUR AB - Laser beam melting (LBM) is an advanced manufacturing technology providing special features and the possibility to produce complex and individual parts directly from a CAD model. TiAl6V4 is the most common used titanium alloy particularly in biomedical applications. TiAl6Nb7 shows promising improvements especially regarding biocompatible properties due to the substitution of the hazardous vanadium. This work focuses on the examination of laser beam melted TiAl6Nb7. For microstructural investigation scanning electron microscopy including energydispersive x-ray spectroscopy as well as electron backscatter diffraction are utilized. The laser beam melted related acicular microstructure as well as the corresponding mechanical properties, which are determined by hardness measurements and tensile tests, are investigated. The laser beam melted alloy meets, except of breaking elongation A, the mechanical demands like ultimate tensile strength Rm, yield strength Rp0.2, Vickers hardness HV of international standard ISO 5832-11. Next steps contain comparison between TiAl6Nb7 and TiAl6V4 in different conditions. Further investigations aim at improving mechanical properties of TiAl6Nb7 by heat treatments and assessment of their influence on the microstructure as well as examination regarding the corrosive behavior in human bodylike conditions. AU - Hein, Maxwell AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 24086 JF - Materialwissenschaft und Werkstofftechnik KW - Laser beam melting KW - titanium alloy KW - TiAl6Nb7 KW - biomedical engineering KW - implants SN - 0933-5137 TI - Additively processed TiAl6Nb7 alloy for biomedical applications VL - 52 ER - TY - JOUR AU - Cieslar, Miroslav AU - Králík, Rostislav AU - Bajtošová, Lucia AU - Křivská, Barbora AU - Hájek, Michal AU - Belejová, Sára AU - Grydin, Olexandr AU - Stolbchenko, Mykhailo AU - Schaper, Mirko ID - 29813 IS - S2 JF - Microscopy and Microanalysis KW - Instrumentation SN - 1431-9276 TI - High Temperature Annealing of Twin-Roll Cast Al-Li-Based Alloy Studied by In-situ SEM and STEM VL - 27 ER - TY - JOUR AU - Krüger, Jan Tobias AU - Hoyer, Kay-Peter AU - Filor, Viviane AU - Pramanik, Sudipta AU - Kietzmann, Manfred AU - Meißner, Jessica AU - Schaper, Mirko ID - 41514 JF - Journal of Alloys and Compounds KW - Materials Chemistry KW - Metals and Alloys KW - Mechanical Engineering KW - Mechanics of Materials SN - 0925-8388 TI - Novel AgCa and AgCaLa alloys for Fe-based bioresorbable implants with adapted degradation VL - 871 ER - TY - JOUR AU - Křivská, Barbora AU - Šlapáková, Michaela AU - Minárik, Peter AU - Fekete, Klaudia AU - Králík, Rostislav AU - Stolbchenko, Mykhailo AU - Schaper, Mirko AU - Grydin, Olexandr ID - 29814 IS - S2 JF - Microscopy and Microanalysis KW - Instrumentation SN - 1431-9276 TI - Intermetallic Phase Growth in Al-steel Clad Strip during In-situ Heating in TEM VL - 27 ER - TY - JOUR AU - Pramanik, Sudipta AU - Tasche, Lennart AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 41515 JF - Additive Manufacturing KW - Industrial and Manufacturing Engineering KW - Engineering (miscellaneous) KW - General Materials Science KW - Biomedical Engineering SN - 2214-8604 TI - Investigating the microstructure of an additively manufactured FeCo alloy: an electron microscopy study VL - 46 ER - TY - JOUR AU - Camberg, Alan Adam AU - Andreiev, Anatolii AU - Pramanik, Sudipta AU - Hoyer, Kay-Peter AU - Tröster, Thomas AU - Schaper, Mirko ID - 27700 JF - Materials Science and Engineering: A SN - 0921-5093 TI - Strength enhancement of AlMg sheet metal parts by rapid heating and subsequent cold die stamping of severely cold-rolled blanks ER - TY - JOUR AB - AbstractWithin this research, the multiscale microstructural evolution before and after the tensile test of a FeCo alloy is addressed. X-ray µ-computer tomography (CT), electron backscattered diffraction (EBSD), and transmission electron microscopy (TEM) are employed to determine the microstructure on different length scales. Microstructural evolution is studied by performing EBSD of the same area before and after the tensile test. As a result, $$\langle$$ 001$$\rangle$$ ||TD, $$\langle$$ 011$$\rangle$$ ||TD are hard orientations and $$\langle$$ 111$$\rangle$$ ||TD is soft orientations for deformation accommodation. It is not possible to predict the deformation of a single grain with the Taylor model. However, the Taylor model accurately predicts the orientation of all grains after deformation. {123}$$\langle$$ 111$$\rangle$$ is the most active slip system, and {112}$$\langle$$ 111$$\rangle$$ is the least active slip system. Both EBSD micrographs show grain subdivision after tensile testing. TEM images show the formation of dislocation cells. Correlative HRTEM images show unresolved lattice fringes at dislocation cell boundaries, whereas resolved lattice fringes are observed at dislocation cell interior. Since Schmid’s law is unable to predict the deformation behavior of grains, the boundary slip transmission accurately predicts the grain deformation behavior. AU - Pramanik, Sudipta AU - Tasche, Lennart AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 24090 JF - Journal of Materials Engineering and Performance SN - 1059-9495 TI - Correlation between Taylor Model Prediction and Transmission Electron Microscopy-Based Microstructural Investigations of Quasi-In Situ Tensile Deformation of Additively Manufactured FeCo Alloy ER - TY - JOUR AB - Purpose The currently existing restrictions regarding the deployment of additively manufactured components because of poor surface roughness, porosity and residual stresses as well as their influence on the low-cycle fatigue (LCF) strength are addressed in this paper. Design/methodology/approach This study aims to evaluating the effect of different pre- and post-treatments on the LCF strength of additively manufactured 316L parts. Therefore, 316L specimens manufactured by laser powder bed fusion were examined in their as-built state as well as after grinding, or coating with regard to the surface roughness, residual stresses and LCF strength. To differentiate between topographical effects and residual stress-related phenomena, stress-relieved 316L specimens served as a reference throughout the investigations. To enable an alumina coating of the 316L components, atmospheric plasma spraying was used, and the near-surface residual stresses and the surface roughness are measured and investigated. Findings The results have shown that the applied pre- and post-treatments such as stress-relief heat treatment, grinding and alumina coating have each led to an increase in LCF strength of the 316L specimens. In contrast, the non-heat-treated specimens predominantly exhibited coating delamination. Originality/value To the best of the authors’ knowledge, this is the first study of the correlation between the LCF behavior of additively manufactured uncoated 316L specimens in comparison with additively manufactured 316L specimens with an alumina coating. AU - Garthe, Kai-Uwe AU - Hoyer, Kay-Peter AU - Hagen, Leif AU - Tillmann, Wolfgang AU - Schaper, Mirko ID - 27509 JF - Rapid Prototyping Journal SN - 1355-2546 TI - Correlation between pre- and post-treatments of additively manufactured 316L parts and the resulting low cycle fatigue behavior ER - TY - JOUR AB - Resorbable implants are highly beneficial to reduce patient burden since they need not be removed after a defined period. Currently, magnesium (Mg) and polymers are being applied as bioresorbable materials. However, for some applications the insufficient mechanical properties and high degradation rate of Mg cause the need for new materials. Iron (Fe)-based alloys are promising due to their biocompatibility and good mechanical properties, but their degradation rate is too low and needs to be adapted eg. via alloying with manganese (Mn). Besides, phases with high electrochemical potential lead to increased degradation of residual material with lower potential based on the galvanic coupling. Here, silver (Ag) is promising for the formation of such phases due to its high electrochemical potential (+0.8 V vs. SHE), immiscibility with Fe, biocompatibility, and anti-bacterial properties. Since remaining silver particles can lead to adverse consequences as thrombosis, these particles need to dissolve after the matrix material. Thus a silver alloy with high electrochemical potential, biocompatibility, and adjusted degradation behavior is required as an additive for iron-based bioresorbable materials. Several silver alloying systems are possible, but regarding the electrochemical potential and degradation behavior of binary alloys, calcium (Ca) and lanthanum (La) are best-suited considering their biocompatibility. Accordingly, this research addresses AgCa and AgCaLa alloys as additives for iron-based degradable materials with adapted degradation behavior. AU - Krüger, Jan Tobias AU - Hoyer, Kay-Peter AU - Filor, Viviane AU - Pramanik, Sudipta AU - Kietzmann, Manfred AU - Meißner, Jessica AU - Schaper, Mirko ID - 24087 JF - Journal of Alloys and Compounds SN - 0925-8388 TI - Novel AgCa and AgCaLa alloys for Fe-based bioresorbable implants with adapted degradation ER - TY - JOUR AB - Implementing the concept of mixed construction in modern automotive engineering requires the joining of sheet metal or extruded profiles with cast components made from different materials. As weight reduction is desired, these cast components are usually made from high-strength aluminium alloys of the Al-Si (Mn, Mg) system, which have limited weldability. The mechanical joinability of the cast components depends on their ductility, which is influenced by the microstructure. High-strength cast aluminium alloys have relatively low ductility, which leads to cracking of the joints. This limits the range of applications for cast aluminium alloys. In this study, an aluminium alloy of the Al-Si system AlSi9 is used to investigate relationships between solidification conditions during the sand casting process, microstructure, mechanical properties, and joinability. The demonstrator is a stepped plate with a minimum thickness of 2.0 mm and a maximum thickness of 4.0 mm, whereas the thickness difference between neighbour steps amounts to 0.5 mm. During casting trials, the solidification rates for different plate steps were measured. The microscopic investigations reveal a correlation between solidification rates and microstructure parameters such as secondary dendrite arm spacing. Furthermore, mechanical properties and the mechanical joinability are investigated. AU - Neuser, Moritz AU - Grydin, Olexandr AU - Andreiev, Anatolii AU - Schaper, Mirko ID - 23913 JF - Metals SN - 2075-4701 TI - Effect of Solidification Rates at Sand Casting on the Mechanical Joinability of a Cast Aluminium Alloy ER - TY - JOUR AB - AbstractLaser surface treatment of metals is one option to improve their properties for adhesive bonding. In this paper, a pulsed YVO4 Laser source with a wavelength of 1064 nm and a maximum power of 25 W was utilized to increase the surface area of the steel HCT490X in order to improve its bonding properties with a carbon fibre reinforced polymer (CFRP). Investigated was the influence of the scanning speed of the laser source on the bonding properties. For this purpose, the steel surfaces were ablated at a scanning speed between 1500 and 4500 mm/s. Afterwards the components were bonded with the adhesive HexBond™ 677. After lap shear tests were carried out on the specimen, the surfaces were inspected using scanning electron microscopy (SEM). The experiments revealed that the bonding quality can be improved with a high scanning speed, even when the surface is not completely ablated. AU - Voswinkel, Dietrich AU - Kloidt, D. AU - Grydin, Olexandr AU - Schaper, Mirko ID - 24565 IS - 2 JF - Production Engineering SN - 0944-6524 TI - Time efficient laser modification of steel surfaces for advanced bonding in hybrid materials VL - 15 ER - TY - JOUR AU - Engelkemeier, Katja AU - Sun, Aijia AU - Voswinkel, Dietrich AU - Grydin, Olexandr AU - Schaper, Mirko AU - Bremser, Wolfgang ID - 24566 JF - ChemElectroChem SN - 2196-0216 TI - Zinc Anodizing: Structural Diversity of Anodic Zinc Oxide Controlled by the Type of Electrolyte ER - TY - JOUR AU - Andreiev, Anatolii AU - Hoyer, Kay-Peter AU - Dula, Dimitri AU - Hengsbach, Florian AU - Grydin, Olexandr AU - Frolov, Yaroslav AU - Schaper, Mirko ID - 23897 JF - Materials Science and Engineering: A SN - 0921-5093 TI - Laser beam melting of functionally graded materials with application-adapted tailoring of magnetic and mechanical performance ER - TY - JOUR AU - Pramanik, Sudipta AU - Andreiev, Anatolii AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 23911 JF - International Journal of Fatigue SN - 0142-1123 TI - Quasi in-situ analysis of fracture path during cyclic loading of double-edged U notched additively manufactured FeCo alloy ER - TY - JOUR AU - Pramanik, Sudipta AU - Tasche, Lennart AU - Hoyer, Kay-Peter AU - Schaper, Mirko ID - 24088 JF - Additive Manufacturing SN - 2214-8604 TI - Investigating the microstructure of an additively manufactured FeCo alloy: an electron microscopy study ER - TY - JOUR AU - Reitz, Alexander AU - Grydin, Olexandr AU - Schaper, Mirko ID - 23803 JF - Materials Data for Smart Forming Technologies TI - Characterization of phase transformations during graded thermo- mechanical treatment of steel 22MnB5 by means of optical methods ER - TY - JOUR AU - Wallmeier, Nadine ID - 37239 JF - Kreis Höxter Jahrbuch TI - Plattdeutsch im Kreis Höxter. "Der Dialektatlas Mittleres Westdeutschland (DMW)" und die Frage "Wie klingt Plattdeutsch im Kreis Höxter?" ER - TY - BOOK AU - Tophinke, Doris AU - Wallmeier, Nadine AU - Merten, Marie-Luis ID - 22515 TI - Das paderbörnische Platt. Niederdeutsch im Gebiet der Kreise Paderborn und Höxter ER - TY - CONF AU - Mutschler, Tanja AU - Buschhüter, David AU - Schröder, Jan AU - Riese, Josef AU - Borowski, Andreas ED - Habig, Sebastian ID - 45449 T2 - Naturwissenschaftlicher Unterricht und Lehrerbildung im Umbruch? Gesellschaft für Didaktik der Chemie und Physik. Online Jahrestagung 2020 TI - Theoriekonformität von Unterrichtsplanungen im Fach Physik vor und nach dem Praxissemester VL - 41 ER - TY - CONF AU - Große-Heilmann, Rike Isabel AU - Riese, Josef ED - Habig, Sebastian ID - 45461 T2 - Naturwissenschaftlicher Unterricht und Lehrerbildung im Umbruch? Gesellschaft für Didaktik der Chemie und Physik. Online Jahrestagung 2020. Essen: Universität Duisburg-Essen TI - Erwerb physikdidaktischen Wissens zum Einsatz digitaler Medien im Physikunterricht VL - 41 ER - TY - CONF AU - Joswig-Käfer, Ann-Kathrin AU - Riese, Josef ED - Habig, Sebastian ID - 45460 T2 - Naturwissenschaftlicher Unterricht und Lehrerbildung im Umbruch? Gesellschaft für Didaktik der Chemie und Physik. Online Jahrestagung 2020. Essen: Universität Duisburg-Essen TI - Längsschnitt Physikdidaktischen Wissens: Ursachen für Veränderungen VL - 41 ER - TY - CONF AU - Ermel, Dorothee AU - Riese, Josef ED - Habig, Sebastian ID - 45463 T2 - Naturwissenschaftlicher Unterricht und Lehrerbildung im Umbruch? Gesellschaft für Didaktik der Chemie und Physik. Online Jahrestagung 2020. Essen: Universität Duisburg-Essen TI - Praktische technische Kompetenzen im Techniklehramt VL - 41 ER - TY - CONF AU - Albert, Gerrit AU - Riese, Josef ED - Habig, Sebastian ID - 45462 T2 - Naturwissenschaftlicher Unterricht und Lehrerbildung im Umbruch? Gesellschaft für Didaktik der Chemie und Physik. Online Jahrestagung 2020. Essen: Universität Duisburg-Essen TI - Digitale Kompetenzen im Techniklehramt VL - 41 ER - TY - CONF AU - Schröder, Jan AU - Vogelsang, Christoph AU - Riese, Josef ID - 45450 T2 - Naturwissenschaftlicher Unterricht und Lehrerbildung im Umbruch? Gesellschaft für Didaktik der Chemie und Physik. Online Jahrestagung 2020 TI - Entwicklung der Fähigkeit zur Unterrichtsplanung im Fach Physik VL - 41 ER - TY - JOUR AU - Masendorf, Lukas AU - Wächter, Michael AU - Esderts, Alfons AU - Otroshi, Mortaza AU - Meschut, Gerson ID - 21545 JF - Fatigue & Fracture of Engineering Materials & Structures SN - 8756-758X TI - Service life estimation of self‐piercing riveted joints by linear damage accumulation ER - TY - JOUR AB - We consider a measure given as the continuum limit of a one-dimensional Ising model with long-range translationally invariant interactions. Mathematically, the measure can be described by a self-interacting Poisson driven jump process. We prove a correlation inequality, estimating the magnetic susceptibility of this model, which holds for small norm of the interaction function. The bound on the magnetic susceptibility has applications in quantum field theory and can be used to prove existence of ground states for the spin boson model. AU - Hasler, David AU - Hinrichs, Benjamin AU - Siebert, Oliver ID - 43493 JF - Stochastic Processes and their Applications SN - 0304-4149 TI - Correlation bound for a one-dimensional continuous long-range Ising model VL - 146 ER - TY - CONF AU - Schubert, Philipp AU - Hermann, Ben AU - Bodden, Eric AU - Leer, Richard ID - 26406 T2 - SCAM '21: IEEE International Working Conference on Source Code Analysis and Manipulation (Engineering Track) TI - Into the Woods: Experiences from Building a Dataflow Analysis Framework for C/C++ ER - TY - CONF AU - Schubert, Philipp AU - Sattler, Florian AU - Schiebel, Fabian AU - Hermann, Ben AU - Bodden, Eric ID - 26405 T2 - 2021 IEEE 21st International Working Conference on Source Code Analysis and Manipulation (SCAM) TI - Modeling the Effects of Global Variables in Data-Flow Analysis for C/C++ ER - TY - CONF AB - We present a monolithically integrated electronic-photonic Mach-Zehnder modulator with a linear, segmented driver on the same silicon substrate. As metric for the modulation efficiency, the external V$\pi$ is hereby reduced to only 420 mV. AU - Kress, Christian AU - Singh, Karanveer AU - Schwabe, Tobias AU - Preußler, Stefan AU - Schneider, Thomas AU - Scheytt, J. Christoph ID - 29203 KW - Analog to digital converters KW - Extinction ratios KW - Grating couplers KW - Modulation KW - Modulators KW - Phase shift T2 - OSA Advanced Photonics Congress 2021 TI - High Modulation Efficiency Segmented Mach-Zehnder Modulator Monolithically Integrated with Linear Driver in 0.25 \textmum BiCMOS Technology ER - TY - JOUR AB - An analysis of an optical Nyquist pulse synthesizer using Mach-Zehnder modulators is presented. The analysis allows to predict the upper limit of the effective number of bits of this type of photonic digital-to-analog converter. The analytical solution has been verified by means of electro-optic simulations. With this analysis the limiting factor for certain scenarios: relative intensity noise, distortions by driving the Mach-Zehnder modulator, or the signal generator phase noise can quickly be identified. AU - Kress, Christian AU - Bahmanian, Meysam AU - Schwabe, Tobias AU - Scheytt, J. Christoph ID - 29204 IS - 15 JF - Opt. Express KW - Analog to digital converters KW - Diode lasers KW - Laser sources KW - Phase noise KW - Signal processing KW - Wavelength division multiplexers TI - Analysis of the effects of jitter, relative intensity noise, and nonlinearity on a photonic digital-to-analog converter based on optical Nyquist pulse synthesis VL - 29 ER - TY - THES AU - Fanasch, Patrizia ID - 45670 TI - Governance and Reputation in the Market for Experience Goods ER - TY - JOUR AB - The role of domain-specific content knowledge is discussed controversially for the early childhood context. Therefore, this review aims at untangling the research on domain-specific content knowledge for early childhood educators by systematically reviewing the conceptual and operational definition of and results on early childhood educators' content knowledge in different domains. Using the scientific databases ERIC, PsycInfo and Web of Sciences, we identified 36 studies on early childhood educators' domain-specific content knowledge. By comparing these studies, we found that conceptualizations of early childhood educators' content knowledge move on a continuum between a scientific related perspective and a practice related perspective. The scientific related perspective defines content knowledge as the knowledge of key concepts, facts and rules of the domain integrating knowledge taught in primary, secondary or upper secondary school. The practice related perspective includes knowledge of key concepts, facts and rules of the domain limited to the knowledge explicitly relevant for teaching in early childhood education as well as selected domain-specific knowledge of children and teaching. Our review shows that the results and implications drawn by the study authors depend on how these authors conceptualize early childhood educators' content knowledge on this continuum. Further research, therefore, needs to consider carefully how early childhood educators' content knowledge is conceptualized. The paper further discusses gaps in this research field, such as validating methods for measuring early childhood educators' content knowledge or implementing more rigorous experimental designs to examine effects of early childhood educators' content knowledge. AU - Bruns, Julia AU - Gasteiger, Hedwig AU - Strahl, Carolin ID - 34822 IS - 2 JF - Review of Education KW - content knowledge KW - domain-specific learning KW - early childhood education KW - teacher knowledge SN - 2049-6613 TI - Conceptualising and measuring domain-specific content knowledge of early childhood educators: A systematic review VL - 9 ER - TY - JOUR AU - Bruns, Julia AU - Schopferer, T. ID - 45687 JF - . TPS – Theorie und Praxis der Sozialpädagogik TI - Eine mustergültige Wissenschaft VL - 11 ER - TY - CONF AU - Jensen, Solveig AU - Gasteiger, Hedwig AU - Bruns, Julia ED - Inprasitha, Maitree ED - Changsri, Narumon ED - Boonsena, Nisakorn ID - 36527 T2 - Proceedings of the 44th Conference of the International Group for the Psychology of Mathematics Education TI - Place value and regrouping as seperate constructs of place value understanding VL - 3 ER - TY - JOUR AU - Bruns, Julia AU - Gasteiger, Hedwig AU - Strahl, Carolin ID - 34823 IS - 2 JF - Review of Education SN - 2049-6613 TI - Context and Implications Document for: Conceptualising and measuring domain-specific content knowledge of early childhood educators: A systematic review VL - 9 ER - TY - CONF AU - Jensen, Solveig AU - Gasteiger, Hedwig AU - Bruns, Julia ID - 36536 T2 - Beiträge zum Mathematikunterricht 2021 TI - Stellenwertverständnis: Verständnis von Stellenwertprinzip und Bündelungsprinzip als separate Konstrukte ER - TY - JOUR AU - Schönherr, Johanna AU - Blomberg, J. AU - Schukajlow, S. AU - Leopold, C. ID - 45342 JF - Contemporary Educational Psychology TI - Do emotions and prior performance facilitate the use of the learner-generated drawing strategy? Effects of enjoyment, anxiety, and intramathematical performance on the use of the drawing strategy and modelling performance VL - 65 ER - TY - JOUR AU - Schönherr, Johanna AU - Schukajlow, S. AU - Blomberg, J. AU - Leopold, C. ID - 45333 JF - Mathematical Thinking and Learning TI - Does strategic knowledge matter? Effects of strategic knowledge about drawing on students’ modeling competencies in the domain of geometry ER - TY - JOUR AU - Schönherr, Johanna AU - Schukajlow, S. AU - Blomberg, J. AU - Leopold, C. ID - 45343 JF - Learning and Instruction TI - The role of strategy-based motivation in mathematical problem solving: The case of learner-generated drawings VL - 80 ER - TY - JOUR AU - Schönherr, Johanna AU - Schukajlow, S. AU - Blomberg, J. ID - 45335 JF - mathematik lehren TI - Was ist eine gute Skizze? Strategiewissen beim mathematischen Modellieren im Bereich der Geometrie fördern VL - 224 ER - TY - CHAP AU - Herding, Jana AU - Büker, P. AU - Kamin, A.M. AU - Glawe, K. AU - Oevel, Gudrun AU - Knurr, M. AU - Menke, I. AU - Ogrodowski, J. AU - Schaper, F. ED - Wollersheim, Hans Werner ED - Pengel, Norbert ID - 45352 T2 - Bildung in der digitalen Transformation TI - inklud.nrw – eine fallbasierte Lehr-/Lernumgebung zum Erwerb inklusions- und digitalisierungsbezogener Kompetenzen in der Lehrer:innenbildung ER - TY - CHAP AU - Herding, Jana AU - Ogrodowski, J. ED - Böhme, N. ID - 45355 T2 - Mythen, Widersprüche und Gewissheiten der Grundschulforschung. Eine wissenschaftliche Bestandsaufnahme nach 100 Jahren Grundschule. Jahrbuch Grundschulforschung TI - Mit Kindern den Übergang auf die weiterführende Schule reflektieren – Sichtweisen von Viertklässler*innen auf die selektiven Schulstrukturen VL - 25 ER - TY - JOUR AU - Herding, Jana AU - Höke, J. AU - Büker, P. AU - Ogrodowski, J. ID - 45353 IS - 3 JF - Diskurs Kindheits- und Jugendforschung/Discourse. Journal of Childhood and Adolescence Research TI - Paderborner Qualitätsstern (PQ³) zur Einschätzung der Kooperation im Übergang Kita – Grundschule: ein Selbstevaluationsinstrument für multiprofessionelle und institutionsübergreifende Zusammenarbeit VL - 16 ER - TY - CHAP AU - Herding, Jana AU - Büker, P. AU - Höke, J. AU - Ogrodowski, J. ED - Dockett, Sue ED - Perry, Bob ID - 45354 T2 - Evaluation Transition to School Programms: Learning from Research and Practice TI - Paderborner Qualitätsstern (PQ³): Self-evaluation of transition to school programms for educators and teachers ER - TY - GEN AU - Herding, Jana ID - 45358 TI - KrafT Bildungsdokumentation: Kind- und ressourcenorientierte, analysebasierte, fortschrittsorientierte Bildungsbegleitung im Team planen, dokumentieren und reflektieren. Herausgegeben von: Büker, Petra; Ogrodowski, Jana, und Antenbrink, Teresa ER - TY - CONF AU - Mattei, Annalisa AU - Eremin, Oxana ID - 45326 T2 - Bericht zur Jahrestagung der Sektion Frauen- und Geschlechterforschung in der Erziehungswissenschaft in der Deutschen Gesellschaft für Erziehungswissenschaft TI - Corona und Krise. Perspektiven erziehungswissenschaftlicher Frauen- und Geschlechterforschung ER - TY - GEN AU - Mattei, Annalisa ID - 45328 T2 - Jahrbuch Erziehungswissenschaftliche Geschlechterforschung 17, Opladen / Berlin / Toronto TI - Rezension zu: Nef, Susanne: Ringen um Bedeutung. Die Deutung häuslicher Gewalt als sozialer Prozess, Basel 2020, in: Fegter, Susann / Langer, Antje / Thon, Christine (Hgg.): Diskursanalytische Geschlechterforschung in der Erziehungswissenschaft ER - TY - GEN AU - Mattei, Annalisa AU - Eremin, Oxana ID - 45327 TI - Jahrestagung „Corona und Krise – Perspektiven erziehungswissenschaftlicher Frauen- und Geschlechterforschung“ Erziehungswissenschaft Heft 63, Jg. 32|2021 ER - TY - CHAP AU - Schemmer, Susanne Jutta AU - Heisler, Dietmar AU - Rink, Julia ED - Weyland, Ulrike ED - Ziegler, Birgit ED - Driesel-Lange, Katja ED - Kruse, Annika ID - 45319 T2 - Entwicklungen und Perspektiven in der Berufsorientierung. Stand und Herausforderungen. Online: (06.12.2021) TI - Entwicklungschance oder Warteschleife? Berufsorientierung und Berufswahl in der Berufsfachschule ER - TY - JOUR AU - Aghaei Abrandabadi, Seyed Ali AU - Marx, Michael ID - 45698 JF - Journal of Iranian National Museum, 2 TI - Carbon Dating of Seven Parchment Qurʾān Manuscripts and One Syriac Bible of the National Museum of Iran ER - TY - CHAP AU - Saad, Nadia ID - 45706 T2 - Erlanger Jahrbuch für Interreligiöse Diskurse. Methoden der Darstellung und Analyse interreligiöser Diskurse TI - David und Salomon im Koran: ein Komparativ-theologischer Ansatz ER - TY - JOUR AU - Zahera, H.M.A AU - Jalota, Rricha AU - Sherif, Mohamed Ahmed AU - Ngomo, Axel-Cyrille Ngonga ID - 30372 JF - IEEE Access KW - General Engineering KW - General Materials Science KW - General Computer Science SN - 2169-3536 TI - I-AID: Identifying Actionable Information From Disaster-Related Tweets VL - 9 ER - TY - CONF AU - Zahera, H.M.A AU - Heindorf, Stefan AU - Ngomo, Axel-Cyrille Ngonga ID - 30374 T2 - Proceedings of the 11th on Knowledge Capture Conference TI - ASSET: A Semi-supervised Approach for Entity Typing in Knowledge Graphs ER - TY - THES AU - Szopinski, Daniel ID - 24884 TI - Essays on Modeling Languages and Software Tools for Business Model Innovation: Theory and Empirical Evidence ER - TY - CONF AB - Argumentation is a widely applied framework for modeling and evaluating arguments and its reasoning with various applications. Popular frameworks are abstract argumentation (Dung’s framework) or logic-based argumentation (Besnard-Hunter’s framework). Their computational complexity has been studied quite in-depth. Incorporating treewidth into the complexity analysis is particularly interesting, as solvers oftentimes employ SAT-based solvers, which can solve instances of low treewidth fast. In this paper, we address whether one can design reductions from argumentation problems to SAT-problems while linearly preserving the treewidth, which results in decomposition-guided (DG) reductions. It turns out that the linear treewidth overhead caused by our DG reductions, cannot be significantly improved under reasonable assumptions. Finally, we consider logic-based argumentation and establish new upper bounds using DG reductions and lower bounds. AU - Fichte, Johannes AU - Hecher, Markus AU - Mahmood, Yasir AU - Meier, Arne ID - 45840 T2 - Proceedings of the Thirtieth International Joint Conference on Artificial Intelligence TI - Decomposition-Guided Reductions for Argumentation and Treewidth ER - TY - JOUR AB - AbstractDependence Logic was introduced by Jouko Väänänen in 2007. We study a propositional variant of this logic(PDL)and investigate a variety of parameterisations with respect to central decision problems. The model checking problem (MC) ofPDLisNP-complete (Ebbing and Lohmann, SOFSEM 2012). The subject of this research is to identify a list of parameterisations (formula-size, formula-depth, treewidth, team-size, number of variables) under which MC becomes fixed-parameter tractable. Furthermore, we show that the number of disjunctions or the arity of dependence atoms (dep-arity) as a parameter both yield a paraNP-completeness result. Then, we consider the satisfiability problem (SAT) which classically is known to beNP-complete as well (Lohmann and Vollmer, Studia Logica 2013). There we are presenting a different picture: under team-size, or dep-arity SAT isparaNP-complete whereas under all other mentioned parameters the problem isFPT. Finally, we introduce a variant of the satisfiability problem, asking for a team of a given size, and show for this problem an almost complete picture. AU - Mahmood, Yasir AU - Meier, Arne ID - 45849 IS - 2-3 JF - Annals of Mathematics and Artificial Intelligence KW - Applied Mathematics KW - Artificial Intelligence SN - 1012-2443 TI - Parameterised complexity of model checking and satisfiability in propositional dependence logic VL - 90 ER - TY - CONF AU - Kontinen, Juha AU - Meier, Arne AU - Mahmood, Yasir ID - 45846 SN - 0302-9743 T2 - Logical Foundations of Computer Science TI - A Parameterized View on the Complexity of Dependence Logic ER - TY - JOUR AB - I study a dynamic variant of the Dixit–Stiglitz (Am Econ Rev 67(3), 1977) model of monopolistic competition by introducing price stickiness à la Fershtman and Kamien (Econometrica 55(5), 1987). The analysis is restricted to bounded quantity and price paths that fulfill the necessary conditions for an open-loop Nash equilibrium. I show that there exists a symmetric steady state and that its stability depends on the degree of product differentiation. When moving from complements to perfect substitutes, the steady state is either a locally asymptotically unstable (spiral) source, a stable (spiral) sink or a saddle point. I further apply the Hopf bifurcation theorem and prove the existence of limit cycles, when passing from a stable to an unstable steady state. Lastly, I provide a numerical example and show that there exists a stable limit cycle. AU - Hoof, Simon ID - 45640 IS - 2 JF - Journal of Optimization Theory and Applications SN - 1573-2878 TI - Dynamic Monopolistic Competition VL - 189 ER - TY - GEN AB - Aggregation metrics in reputation systems are important for overcoming information overload. When using these metrics, technical aggregation functions such as the arithmetic mean are implemented to measure the valence of product ratings. However, it is unclear whether the implemented aggregation functions match the inherent aggregation patterns of customers. In our experiment, we elicit customers' aggregation heuristics and contrast these with reference functions. Our findings indicate that, overall, the arithmetic mean performs best in comparison with other aggregation functions. However, our analysis on an individual level reveals heterogeneous aggregation patterns. Major clusters exhibit a binary bias (i.e., an over-weighting of moderate ratings and under-weighting of extreme ratings) in combination with the arithmetic mean. Minor clusters focus on 1-star ratings or negative (i.e., 1-star and 2-star) ratings. Thereby, inherent aggregation patterns are neither affected by variation of provided information nor by individual characteristics such as experience, risk attitudes, or demographics. AU - van Straaten, Dirk AU - Melnikov, Vitalik AU - Hüllermeier, Eyke AU - Mir Djawadi, Behnud AU - Fahr, René ID - 45616 TI - Accounting for Heuristics in Reputation Systems: An Interdisciplinary Approach on Aggregation Processes VL - 72 ER - TY - GEN AU - van Straaten, Dirk ID - 45617 TI - Incentive Schemes in Customer Rating Systems - Comparing the Effects of Unconditional and Conditional Rebates on Intrinsic Motivation VL - 71 ER - TY - GEN AU - van Straaten, Dirk AU - Fahr, René ID - 45618 TI - Fighting Fire with Fire - Overcoming Ambiguity Aversion by Introducing more Ambiguity VL - 73 ER - TY - GEN AU - Bülling, Jonas ID - 45788 TI - Political Speaker Transfer: Learning to Generate Text in the Styles of Barack Obama and Donald Trump ER - TY - GEN AU - Mishra, Avishek ID - 45787 TI - Computational Text Professionalization using Neural Sequence-to-Sequence Models ER - TY - CONF AU - Clausing, Lennart ID - 30909 T2 - Proceedings of the 11th International Symposium on Highly Efficient Accelerators and Reconfigurable Technologies TI - ReconOS64: High-Performance Embedded Computing for Industrial Analytics on a Reconfigurable System-on-Chip ER - TY - JOUR AU - Black, Tobias AU - Fuest, Mario AU - Lankeit, Johannes ID - 34673 IS - 3 JF - Zeitschrift für angewandte Mathematik und Physik KW - Applied Mathematics KW - General Physics and Astronomy KW - General Mathematics SN - 0044-2275 TI - Relaxed parameter conditions for chemotactic collapse in logistic-type parabolic–elliptic Keller–Segel systems VL - 72 ER - TY - JOUR AU - Black, Tobias AU - Wu, Chunyan ID - 34675 IS - 4 JF - Zeitschrift für angewandte Mathematik und Physik KW - Applied Mathematics KW - General Physics and Astronomy KW - General Mathematics SN - 0044-2275 TI - Prescribed signal concentration on the boundary: Weak solvability in a chemotaxis-Stokes system with proliferation VL - 72 ER -