TY - CHAP
AU - Eke, Norbert Otto
ED - Gather, Katharina
ID - 19101
T2 - Zwischen Emanzipation und Sozialdisziplinierung: Pädagogik im Vormärz
TI - Habitueller Antiklassizismus. Christian Dietrich Grabbe und die Kritik an Klassik und Romantik im Vormärz
ER -
TY - JOUR
AU - Vascellari, A
AU - Grassi, A
AU - Canata, GL
AU - Zaffagnini, S
AU - Gokeler, A
AU - Jones, H
ID - 20414
JF - Knee Surg Sports Traumatol Arthrosc
SN - 0942-2056
TI - Hamstrings substitution via anteromedial portal with optional anterolateral ligament reconstruction is the preferred surgical technique for anterior cruciate ligament reconstruction: a survey among ESSKA members.
ER -
TY - BOOK
ED - Albus, Vanessa
ED - Schalk, Helge
ID - 50636
TI - Handbuch Medien im Philosophie- und Ethikunterricht
ER -
TY - GEN
AU - Peckhaus, Volker
ID - 18996
T2 - Mathematical Reviews
TI - Hanke, Miroslav, “The Probabilistic Logic of Eusebius Amort (1692–1775)”, In: Early Science and Medicine 24 (2019), 186–211
ER -
TY - JOUR
AU - Ehland, Christoph
ID - 35505
IS - 3
JF - Critical Survey
TI - Happiness Against All Odds: Incestuous Desires in John Ford’s ’Tis Pity She’s a Whore
VL - 32
ER -
TY - JOUR
AB -
We investigate the structure-activity correlations of methanation catalysts obtained by thermal decomposition of a Ni-based metal-organic framework, using pair distribution function, X-ray absorption spectroscopy and X-ray diffraction.
AU - Prinz, Nils
AU - Schwensow, Leif
AU - Strübbe, Sven
AU - Jentys, Andreas
AU - Bauer, Matthias
AU - Kleist, Wolfgang
AU - Zobel, Mirijam
ID - 41025
IS - 29
JF - Nanoscale
KW - General Materials Science
SN - 2040-3364
TI - Hard X-ray-based techniques for structural investigations of CO2 methanation catalysts prepared by MOF decomposition
VL - 12
ER -
TY - CONF
AB - Historically, the field of financial forecasting almost exclusively relied on so-called hard information – i.e., numerical data with well-defined and unambiguous meaning. Over the last few decades, however, researchers and practitioners alike have, following the advances in natural language understanding, started recognizing the benefits of integrating soft information into financial modelling. In line with the above, this paper examines whether contemporary attention-based sequence-to-sequence models, known as Transformers, can help improve stock return volatility prediction when applied to corporate annual reports. Using a publicly available benchmark dataset, we show, in an empirical analysis, that out-of-the-box Transformer models have the ability to outmatch current state-of-the-art results and, more importantly, that our proposed feature-based Transformer approach can outperform a robust numerical baseline. To the best of our knowledge, this is the first empirical study focusing on stock return volatility prediction (1) to ever experiment with state-of-the-art Transformer architectures and (2) to demonstrate that a model based solely on soft information can surpass its numerical counterpart. Furthermore, we show that by including an additional numerical feature into our best text-only model, we can push the performance of our model even further, suggesting that soft and hard information contain different predictive signals.
AU - Caron, Matthew
AU - Müller, Oliver
ID - 21563
T2 - 2020 IEEE International Conference on Big Data (Big Data)
TI - Hardening Soft Information: A Transformer-Based Approach to Forecasting Stock Return Volatility
ER -
TY - BOOK
ED - Egidi, Margreth
ED - Greulich, Markus
ED - Winter, Marie-Sophie
ID - 31515
TI - Hartmann von Aue 1230–1517. Kulturgeschichtliche Perspektiven der handschriftlichen Überlieferung
ER -
TY - GEN
AU - Budde, Kirsten
AU - Barela, José A
AU - Weigelt, Matthias
ED - Amesberger, Günter
ED - Würth, Sabine
ED - Finkenzeller, Thomas
ID - 48038
T2 - Abstractband der 52. Jahrestagung der Arbeitsgemeinschaft für Sportpsychologie (asp)
TI - Hat die Körperposition (sitzen vs. stehen) einen Einfluss auf die Leistung in einer Mentalen Rotationsaufgabe?
ER -
TY - JOUR
AU - Güldenpenning, Iris
AU - Kunde, Wilfried
AU - Weigelt, Matthias
ID - 37760
IS - 1
JF - International Journal of Sport and Exercise Psychology
KW - Applied Psychology
KW - Social Psychology
SN - 1612-197X
TI - Head-fake perception in basketball: the relative contributions of expertise, visual or motor training, and test repetition
VL - 20
ER -
TY - JOUR
AB - Summary
As health concepts develop through exposure to, and experience with particular contexts, and as health concepts influence health behaviour, it is important for actors in health promotion programmes to understand an individual’s health concepts. This study focussed on health concepts among socially disadvantaged children in France, Germany, Italy and Switzerland—a hitherto less researched population group. We conducted focus groups with a total of 167 children aged 7–11 years (mean=8.76 years, SD=0.68). The aim of this study was to explore if the life situation across four different countries leads to similar health concepts, and how the particular, national health discourses are reflected in the children’s health concepts. The data were analysed through a structured qualitative content analysis and revealed four categories: ‘Symbols/symptoms of health/illness’, ‘Emotionality’, ‘Healthy/unhealthy practices’, and ‘Consequences of health problems’. The children’s health concepts are linked to concrete events and objects, and they are able to think in logical sequences. However, the children’s causal argumentation is uni-dimensional; they do not cover the complexity of the development of health problems. In particular, overweight stands for illness and is exclusively the result of unhealthy practices. In their concepts, the children reflect the national health promotion programme discourses about overweight. They seem to understand the messages of health education as ‘behaving well means being healthy’; however, such a health education message initiates accusations of ‘unhealthy persons’. In consequence, challenges for sensitive health education programmes (at school) are discussed.
AU - Grimminger-Seidensticker, Elke
AU - Aceti, Monica
AU - Knobé, Sandrine
AU - Vieille Marchiset, Gilles
ID - 28343
JF - Health Promotion International
SN - 0957-4824
TI - Health concepts among socially disadvantaged children in France, Germany and Switzerland
VL - 35
ER -
TY - JOUR
AB - Abstract
Purpose
It has been reported that there is no correlation between anterior tibia translation (ATT) in passive and dynamic situations. Passive ATT (ATTp) may be different to dynamic ATT (ATTd) due to muscle activation patterns. This study aimed to investigate whether muscle activation during jumping can control ATT in healthy participants.
Methods
ATTp of twenty-one healthy participants was measured using a KT-1000 arthrometer. All participants performed single leg hops for distance during which ATTd, knee flexion angles and knee flexion moments were measured using a 3D motion capture system. During both tests, sEMG signals were recorded.
Results
A negative correlation was found between ATTp and the maximal ATTd (r = − 0.47, p = 0.028). An N-Way ANOVA showed that larger semitendinosus activity was seen when ATTd was larger, while less biceps femoris activity and rectus femoris activity were seen. Moreover, larger knee extension moment, knee flexion angle and ground reaction force in the anterior-posterior direction were seen when ATTd was larger.
Conclusion
Participants with more ATTp showed smaller ATTd during jump landing. Muscle activation did not contribute to reduce ATTd during impact of a jump-landing at the observed knee angles. However, subjects with large ATTp landed with less knee flexion and consequently showed less ATTd. The results of this study give information on how healthy people control knee laxity during jump-landing.
Level of evidence
III
AU - Keizer, Michèle N. J.
AU - Hijmans, Juha M.
AU - Gokeler, Alli
AU - Benjaminse, Anne
AU - Otten, Egbert
ID - 45126
IS - 1
JF - Journal of Experimental Orthopaedics
KW - Orthopedics and Sports Medicine
SN - 2197-1153
TI - Healthy subjects with lax knees use less knee flexion rather than muscle control to limit anterior tibia translation during landing
VL - 7
ER -
TY - GEN
AU - Keizer, MNJ
AU - Hijmans, JM
AU - Gokeler, A
AU - Benjaminse, A
AU - Otten, E
ID - 20416
IS - 1
SN - 2197-1153
T2 - J Exp Orthop
TI - Healthy subjects with lax knees use less knee flexion rather than muscle control to limit anterior tibia translation during landing.
VL - 7
ER -
TY - CONF
AU - Benz, Manuel
AU - Krogh Kristensen, Erik
AU - Luo, Linghui
AU - P. Borges Jr., Nataniel
AU - Bodden, Eric
AU - Zeller, Andreas
ID - 20510
T2 - International Conference for Software Engineering (ICSE)
TI - Heaps'n Leaks: How Heap Snapshots Improve Android Taint Analysis
ER -
TY - CONF
AB - Heat dissipation is a limiting factor in the performance of many power electronic components. Especially in the TO-263-7 package, which is used for several SiC-MOSFETs, the heat transfer must take place through the cross section of the printed circuit board (PCB) to the heatsink at the bottom side. Most commonly, thermal vias are used to form this path in a perpendicular direction through all PCB-layers. In a given soft- and hard switched example applications with the use of C3M0065090J SiC-MOSFETs, this conventional approach limited the component’s maximum heat dissipation to approx. 13 W. A recent alternative approach are massive copper blocks (”pedestals”) being integrated in PCBs and reaching from their top- to the bottom-side in relevant footprint areas under SMD-housed power semiconductors. Pedestals allowing to increase the heat dissipation in the given case to even 36 W. This step is achieved due to the clearly superior heat spreading capability of that massive thermal connection between SiC-MOSFET and heatsink. For the hard switched example application the number of switch-elements can be halved to one, by using the pedestal instead of thermal vias. Independently of optimizing the heat transfer path, the up-front avoidance of losses helps to stay within existing heat dissipation limits, of course. The dominant conduction losses of the mentioned soft-switched example application could be halved by changing to SiC-MOSFET types with significant lowered RDSon. By using pedestals and changing to SiC-MOSFETs with lowered RDSon, the number of switch-elements can also be halved for the soft switched application.
AU - Strothmann, Benjamin
AU - Piepenbrock, Till
AU - Schafmeister, Frank
AU - Böcker, Joachim
ID - 30001
T2 - PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management
TI - Heat dissipation strategies for silicon carbide power SMDs and their use in different applications
ER -
TY - JOUR
AB - Heat pumps are the key technology to decarbonise thermal processes by upgrading industrial surplus heat using renewable electricity. Existing insight-based integration methods refer to the idealised Grand Composite Curve requiring the full exploitation of heat recovery potential but leave the question of how to deal with technical or economic limitations unanswered. In this work, a novel Heat Pump Bridge Analysis (HPBA) is introduced for practically targeting technical and economic heat pump potential by applying Coefficient of Performance curves into the Modified Energy Transfer Diagram (METD). Removing cross-Pinch violations and operating heat exchangers at minimum approach temperatures by combined application of Bridge Analysis increases the heat recovery rate and reduce the temperature lift to be pumped at the same time. The insight-based METD allows the individual matching of heat surpluses and deficits of individual streams with the capabilities and performance of different market-available heat pump concepts. For an illustrative example, the presented modifications based on HPBA increase the economically viable share of the technical heat pump potential from 61% to 79%.
AU - Schlosser, Florian
AU - Wiebe, Heinrich
AU - Walmsley, Timothy G.
AU - Atkins, Martin J.
AU - Walmsley, Michael R. W.
AU - Hesselbach, Jens
ID - 24630
JF - Energies
SN - 1996-1073
TI - Heat Pump Bridge Analysis Using the Modified Energy Transfer Diagram
ER -
TY - JOUR
AU - Lammer, Christina
AU - Scharlau, Ingrid
ID - 30958
JF - Paderborner Universitätszeitschrift
TI - Herausforderungen für die Chancengleichheit. Online-Mentoring für Studentinnen der Universität Paderborn
ER -
TY - JOUR
AU - Albers, Timm
AU - Weltzien, Dörte
AU - Ali-Tani, Caroline
AU - Döther, Sabrina
AU - Söhnen, Sarah Aileen
AU - Verhoeven, Nadja
ID - 32043
IS - 3
JF - QfI - Qualifizierung für Inklusion. Online-Zeitschrift zur Forschung über Aus-, Fort- und Weiterbildung pädagogischer Fachkräfte
TI - Herausforderungen inklusiver Bildung in Kita-Teams – Konzipierung eines individualisierten Curriculums für Weiterbildung und Prozessbegleitung
VL - 2
ER -
TY - BOOK
AU - Westphal, Petra
ID - 29333
TI - Herausforderungen studentischen Peer-Mentorings. Eine Situationsanalyse vor dem Hintergrund universitärer Arenen
ER -
TY - CONF
AU - Senkbeil, M.
AU - Schwippert, K.
AU - Drossel, Kerstin
AU - Vennemann, M.
ID - 52522
T2 - Vortrag im Rahmen des Symposiums ‚Computer- und informationsbezogene Kompetenzen von Schülerinnen und Schülern im zweiten internationalen Vergleich und Kompetenzen im Bereich ‚Computational Thinking‘ - Befunde der IEA-Studie ICILS 2018 – Teil 1‘ (OrganisatorInnen: Birgit Eickelmann, Wilfried Bos, Julia Gerick & Amelie Labusch, Diskutant: Johannes Naumann) auf der 8. Tagung der Gesellschaft für Empirische Bildungsforschung (GEBF). Universität Potsdam
TI - Herkunftsbedingte Unterschiede in den computer- und informationsbezogenen Kompetenzen von Schülerinnen und Schülern in ICILS 2018 und Ansatzpunkte zur Ermöglichung von Partizipation(angenommen, Konferenz abgesagt)
ER -
TY - GEN
ED - Eke, Norbert Otto
ID - 23853
T2 - edition text + kritik
TI - Herta Müller. Text + Kritik 155/2020. 2. Auflage: Neufassung. Hg. von Norbert Otto Eke und Christof Hamann.
ER -
TY - JOUR
AU - Tanim, Tanvir R.
AU - Paul, Partha P.
AU - Thampy, Vivek
AU - Cao, Chuntian
AU - Steinrück, Hans-Georg
AU - Nelson Weker, Johanna
AU - Toney, Michael F.
AU - Dufek, Eric J.
AU - Evans, Michael C.
AU - Jansen, Andrew N.
AU - Polzin, Bryant J.
AU - Dunlop, Alison R.
AU - Trask, Stephen E.
ID - 23602
JF - Cell Reports Physical Science
SN - 2666-3864
TI - Heterogeneous Behavior of Lithium Plating during Extreme Fast Charging
VL - 1
ER -
TY - JOUR
AB - AbstractFluoride ion batteries (FIBs) are a recent alternative all-solid-state battery technology. However, the FIB systems proposed so far suffer from poor cycling performance. In this work, we report La2NiO4.13 with a Ruddlesden-Popper type structure as an intercalation-based active cathode material in all solid-state FIB with excellent cycling performance. The critical charging conditions to maintain the conductivity of the cell were determined, which seems to be a major obstacle towards improving the cycling stability of FIBs. For optimized operating conditions, a cycle life of about 60 cycles and over 220 cycles for critical cut-off capacities of 50 mAh/g and 30 mAh/g, respectively, could be achieved, with average Coulombic efficiencies between 95 – 99%. Cycling of the cell is a result of fluorination/de-fluorination into and from the La2NiO4+d cathode, and it is revealed that La2NiO4.13 is a multivalent electrode material. Our findings suggest that La2NiO4.13 is a promising high energy cathode for FIBs.
AU - Nowroozi, Mohammad Ali
AU - Wissel, Kerstin
AU - Donzelli, Manuel
AU - Hosseinpourkahvaz, Niloofar
AU - Plana-Ruiz, Sergi
AU - Kolb, Ute
AU - Schoch, Roland
AU - Bauer, Matthias
AU - Malik, Ali Muhammad
AU - Rohrer, Jochen
AU - Ivlev, Sergei
AU - Kraus, Florian
AU - Clemens, Oliver
ID - 41027
IS - 1
JF - Communications Materials
KW - Mechanics of Materials
KW - General Materials Science
SN - 2662-4443
TI - High cycle life all-solid-state fluoride ion battery with La2NiO4+d high voltage cathode
VL - 1
ER -
TY - JOUR
AU - Schryen, Guido
AU - Kliewer, Natalia
AU - Fink, Andreas
ID - 14985
IS - 1
JF - Business & Information Systems Engineering
TI - High Performance Business Computing
VL - 62
ER -
TY - JOUR
AU - Zhao, Jie
AU - Ma, Chaoxuan
AU - Rüsing, Michael
AU - Mookherjea, Shayan
ID - 47952
IS - 16
JF - Physical Review Letters
KW - General Physics and Astronomy
SN - 0031-9007
TI - High Quality Entangled Photon Pair Generation in Periodically Poled Thin-Film Lithium Niobate Waveguides
VL - 124
ER -
TY - CONF
AU - Sharma, Arnab
AU - Wehrheim, Heike
ID - 16724
T2 - Proceedings of the ACM SIGSOFT International Symposium on Software Testing and Analysis (ISSTA).
TI - Higher Income, Larger Loan? Monotonicity Testing of Machine Learning Models
ER -
TY - JOUR
AU - Akrivis, Georgios
AU - Feischl, Michael
AU - Kovács, Balázs
AU - Lubich, Christian
ID - 45955
IS - 329
JF - Mathematics of Computation
KW - Applied Mathematics
KW - Computational Mathematics
KW - Algebra and Number Theory
SN - 0025-5718
TI - Higher-order linearly implicit full discretization of the Landau–Lifshitz–Gilbert equation
VL - 90
ER -
TY - CHAP
AU - Schroeter-Wittke, Harald
AU - Flath, Beate
AU - König, Bernhard
AU - Venus, Viktoria
ED - Helmke, Julia
ED - Rentsch, Stefanie
ID - 41076
SN - 9783579082134
T2 - Deutscher Evangelischer Kirchentag Dortmund 2019. Dokumente
TI - Hiob und das Leiden: Vertrauensfrage - Hiob 2,7-13. Bibelarbeit auf dem Weg am Donnerstag, 20. Juni 2019
ER -
TY - BOOK
AU - Günther, Katrin
ID - 31572
TI - Historisches Vergleichen: Vergleichsaufgaben in Lehrwerken des Gesellschaftslehre- und Geschichtsunterrichts der Sekundarstufe II. Eine Untersuchung von (Schüler*innen-)Lösungen zu einer Vergleichsaufgabe am Beispiel eines Darstellungstextes zur Industriellen Revolution, Bd. 7: Geschichtsdidaktische Studien
ER -
TY - JOUR
AU - Röder, Michael
AU - Kuchelev, Denis
AU - Ngonga Ngomo, Axel-Cyrille
ID - 25326
IS - 1
JF - Data Sci.
TI - HOBBIT: A platform for benchmarking Big Linked Data
VL - 3
ER -
TY - CHAP
AU - Biehler, Rolf
AU - Kempen, Leander
AU - Paravicini, Walther
ED - Siller, H.-S.
ED - Weigel, W.
ED - Wörler, J. F.
ID - 35819
T2 - Beiträge zum Mathematikunterricht 2020
TI - Hochschuldidaktik Mathematik: Fachbezogenes Design und empirische Studien
ER -
TY - GEN
AU - Topalović, Elvira
AU - Uhl, Benjamin
ID - 40924
TI - Hören – Sprechen – Lesen – Schreiben. Basale Sprachfähigkeiten.
ER -
TY - GEN
AU - Topalović, Elvira
AU - Uhl, Benjamin
ID - 40923
TI - Hören – Sprechen – Lesen – Schreiben. Basale Sprachfähigkeiten.
ER -
TY - CONF
AU - Albrecht, Mirko
AU - Bialaschik, Max
AU - Gehde, Michael
AU - Schöppner, Volker
ID - 23873
TI - Hot gas welding – Influences of the tool design
ER -
TY - CONF
AU - Franzen, Katja
AU - Hellmich, Frank
ID - 36211
TI - How can primary school teachers’ self-efficacy beliefs in inclusive education be explained? Single Paper. ECER 2020 (European Conference on Educational Research). “Educational Research (Re)connecting Communities”
ER -
TY - GEN
AB - We analyze the impact of trust on bargaining behavior between auditor and auditee in a tax setting. We study the effect of interpersonal trust and trust in government on both taxpayer and tax auditor. In an experiment with variation in pairwise trust settings, we find evidence that both kinds of trust affect the bargaining behavior, albeit in different ways. While trust in government increases taxpayers’ tax offers, interpersonal trust may lead to more concessionary behavior of tax auditors moderated by trust in government. Our findings help tax authorities to shape programs to enhance compliance in an atmosphere of trust.
AU - Eberhartinger, Eva
AU - Speitmann, Raffael
AU - Sureth-Sloane, Caren
ID - 21410
TI - How Does Trust Affect Concessionary Behavior in Tax Bargaining?
VL - No. 41
ER -
TY - JOUR
AU - Sievers, Sönke
AU - Degen, Dominik
AU - Kim, Daniel
AU - Kengelbach, Jens
ID - 20866
JF - M&A Review Europe
TI - How Private Equity can leverage downturn M&A for value creation
ER -
TY - JOUR
AU - Svartdal, Frode
AU - Dahl, Tove I.
AU - Gamst-Klaussen, Thor
AU - Koppenborg, Markus
AU - Klingsieck, Katrin B.
ID - 29110
JF - Frontiers in Psychology
SN - 1664-1078
TI - How Study Environments Foster Academic Procrastination: Overview and Recommendations
ER -
TY - CONF
AU - Purrmann, Maren
AU - Wünderlich, Nancy
ID - 16116
T2 - Proceedings of the 2020 AMA Winter Academic Conference
TI - How to Build Trust on Peer-to-Peer Platforms: An Investigation of the Antecedents of Peer and Platform Trust
ER -
TY - JOUR
AU - Blömer, Johannes
AU - Brauer, Sascha
AU - Bujna, Kathrin
AU - Kuntze, Daniel
ID - 10790
JF - Advances in Data Analysis and Classification
SN - 1862-5347
TI - How well do SEM algorithms imitate EM algorithms? A non-asymptotic analysis for mixture models
VL - 14
ER -
TY - JOUR
AU - Weber, Jutta
ID - 36261
IS - 2/3
JF - Das Argument
TI - Human-Machine Learning und Digital Commons. K/Ein Manifest
VL - 335, 62. Jg. / Heft 2/3
ER -
TY - JOUR
AB - Large Co-MOF-74 crystals of a few hundred micrometers were prepared by solvothermal synthesis, and their structure and morphology were characterized by scanning electron microscopy (SEM), IR, and Raman spectroscopy. The hydrothermal stability of the material up to 60 °C at 93% relative humidity was verified by temperature-dependent XRD. Proton conductivity was studied by impedance spectroscopy, using a single crystal. By varying the relative humidity (70–95%), temperature (21–60 °C), and orientation of the crystal relative to the electrical potential, it was found that proton conduction occurs predominantly through the linear, unidirectional (1D) micropore channels of Co-MOF-74, and that water molecules inside the channels are responsible for the proton mobility by a Grotthuss-type mechanism.
AU - Javed, Ali
AU - Strauss, Ina
AU - Bunzen, Hana
AU - Caro, Jürgen
AU - Tiemann, Michael
ID - 25899
JF - Nanomaterials
SN - 2079-4991
TI - Humidity-Mediated Anisotropic Proton Conductivity through the 1D Channels of Co-MOF-74
ER -
TY - CHAP
AU - Schulze, Max
ED - Gliem, Vera
ED - Strsembski, Stephan
ID - 48963
KW - Editionen
KW - Kunst
KW - Fotografie
KW - Siebdruck
KW - Farbattentat
T2 - Provinz Editionen 2011-2020
TI - Hunger (Eduardo Chillida) und Swingcolor
ER -
TY - JOUR
AU - Rudic, Biljana
AU - Hubner-Benz, Sylvia
AU - Baum, Matthias
ID - 48521
JF - Journal of Business Venturing Insights
KW - Management of Technology and Innovation
KW - Business and International Management
SN - 2352-6734
TI - Hustlers, hipsters and hackers: Potential employees’ stereotypes of entrepreneurial leaders
VL - 15
ER -
TY - JOUR
AB - A dielectric step-index optical fiber with tube-like profile is considered, being positioned with a small gap on top of a dielectric slab waveguide. We propose a 2.5-D hybrid analytical/numerical coupled mode model for the evanescent excitation of the tube through semi-guided waves propagating in the slab at oblique angles. The model combines the directional polarized modes supported by the slab with analytic solutions for the TE-, TM-, and orbital-angular-momentum (OAM) modes of the tube-shaped fiber. Implementational details of the scheme are discussed, complemented by finite-element simulations for verification purposes. Our results include configurations with resonant in-fiber excitation of OAM modes with large orbital angular momentum and strong field enhancement.
AU - Hammer, Manfred
AU - Ebers, Lena
AU - Förstner, Jens
ID - 20189
JF - Optical and Quantum Electronics
KW - tet_topic_waveguides
SN - 0306-8919
TI - Hybrid coupled mode modelling of the evanescent excitation of a dielectric tube by semi-guided waves at oblique angles
VL - 52
ER -
TY - JOUR
AU - Eckhoff, Marco
AU - Blöchl, Peter E.
AU - Behler, Jörg
ID - 19503
JF - Physical Review B
KW - pc2-ressources
SN - 2469-9950
TI - Hybrid density functional theory benchmark study on lithium manganese oxides
ER -
TY - CONF
AU - Hanselle, Jonas Manuel
AU - Tornede, Alexander
AU - Wever, Marcel Dominik
AU - Hüllermeier, Eyke
ID - 17408
T2 - KI 2020: Advances in Artificial Intelligence
TI - Hybrid Ranking and Regression for Algorithm Selection
ER -
TY - CHAP
AU - Sellmann, Meinolf
AU - Tierney, Kevin
ID - 19561
KW - pc2-ressources
SN - 0302-9743
T2 - Lecture Notes in Computer Science
TI - Hyper-parameterized Dialectic Search for Non-linear Box-Constrained Optimization with Heterogenous Variable Types
ER -
TY - CONF
AB - The continuous innovation of its business models is an important task for a company to stay competitive. During this process, the company has to validate various hypotheses about its business models by adapting to uncertain and changing customer needs effectively and efficiently. This adaptation, in turn, can be supported by the concept of Software Product Lines (SPLs). SPLs reduce the time to market by deriving products for customers with changing requirements using a common set of features, structured as a feature model. Analogously, we support the process of business model adaptation by applying the engineering process of SPLs to the structure of the Business Model Canvas (BMC). We call this concept a Business Model Decision Line (BMDL). The BMDL matches business domain knowledge in the form of a feature model with customer needs to derive hypotheses about the business model together with experiments for validation. Our approach is effective by providing a comprehensive overview of possible business model adaptations and efficient by reusing experiments for different hypotheses. We implement our approach in a tool and illustrate the usefulness with an example of developing business models for a mobile application.
AU - Gottschalk, Sebastian
AU - Rittmeier, Florian
AU - Engels, Gregor
ID - 16933
KW - Business Model Decision Line
KW - Business Model Adaptation
KW - Hypothesis-driven Adaptation
KW - Software Product Line
KW - Feature Model
T2 - Proceedings of the 22nd IEEE International Conference on Business Informatics
TI - Hypothesis-driven Adaptation of Business Models based on Product Line Engineering
ER -
TY - JOUR
AU - M. Zahera, Hamada
AU - Jalota, Rricha
AU - Ahmed Sherif, Mohamed
AU - Ngonga Ngomo, Axel-Cyrille
ID - 25356
JF - CoRR
TI - I-AID: Identifying Actionable Information from Disaster-related Tweets
VL - abs/2008.13544
ER -
TY - JOUR
AU - Teichert, Jeannine
ID - 44201
JF - merzWissenschaft
TI - Ich habe auch Facebook-Freunde“ – Erinnerungspraktiken in vergangenen Freundschaften
VL - 6
ER -
TY - BOOK
ED - Eickelmann, Birgit
ED - Labusch, Amelie
ED - Drossel, Kerstin
ED - Vennemann, Mario
ID - 27858
TI - ICILS 2018 #NRW. Vertiefende Analysen und Befunde für Nordrhein-Westfalen im internationalen Vergleich
ER -
TY - BOOK
AU - Labusch, Amelie
AU - Eickelmann, Birgit
AU - Conze, Daniela
ID - 28905
TI - ICILS 2018 #Transfer. Gestaltung digitaler Schulentwicklung in Deutschland
ER -
TY - JOUR
AU - Eickelmann, Birgit
ID - 28840
JF - Friedrich Jahresheft #schuleDIGITAL
TI - ICILS 2018 – Wo steht Deutschland im internationalen Vergleich?
VL - 38
ER -
TY - CONF
AU - Eickelmann, Birgit
ID - 51992
T2 - Vortrag im Rahmen der Sitzung des wissenschaftlichen Beirats ‚Bildung und Begabung‘. Bonn
TI - ICILS 2018#Deutschland. Computer- und informationsbezogene Kompetenzen von Schülerinnen und Schülern im zweiten internationalen Vergleich und Kompetenzen im Bereich Computational Thinking
ER -
TY - JOUR
AU - Eickelmann, Birgit
AU - Labusch, Amelie
ID - 28847
IS - 5
JF - SchulVerwaltung NRW. Fachzeitschrift für Schulentwicklung und Schulmanagement
TI - ICILS 2018-NRW. Zentrale Ergebnisse und Perspektiven für die Entwicklung schulischer Digitalisierungsprozesse in Nordrhein-Westfalen
VL - 31
ER -
TY - DATA
AU - Teidla-Kunitsõn, Gertha
ID - 27873
TI - ICT usage across Europe: A literature review and an overview of existing data
ER -
TY - DATA
AU - Ayllón, Sara
AU - Barbovschi, Monica
AU - Casamassima, Gianna
AU - Drossel, Kerstin
AU - Eickelmann, Birgit
AU - Ghețău, Cosmin
AU - Haragus, Teo Paul
AU - Holmarsdottir, Halla Bjork
AU - Hyggen, Christer
AU - Kapella, Olaf
AU - Karatzogianni, Athina
AU - Lado, Samuel
AU - Levine, Diane
AU - Lorenz, Theresa
AU - Mifsud, Louise
AU - Parsanoglou, Dimitris
AU - Port, Sonja
AU - Sisask, Merike
AU - Symeonaki, Maria
AU - Teidla-Kunitsõn, Gertha
ID - 27868
TI - ICT usage across Europe: A literature review and an overview of existing data
ER -
TY - CONF
AU - Wortmann, Fabio
AU - Ellermann, Kai
AU - Kühn, Arno
AU - Dumitrescu, Roman
ID - 21386
IS - 91
T2 - Procedia CIRP
TI - Ideation for digital platforms based on a companies‘ ecosystem
ER -
TY - CONF
AU - Henkenjohann, Mark
AU - Joppen, Robert
AU - Köchling, Daniel
AU - von Enzberg, Sebastian
AU - Kühn, Arno
AU - Dumitrescu, Roman
ID - 21392
T2 - Procedia CIRP
TI - Identification and specification of standard modules in production for a material flow simulation
ER -
TY - CONF
AU - Schnasse, Felix
AU - Menzefricke, Jörn Steffen
AU - Gabriel, Stefan
AU - Hobscheidt, Daniela
AU - Parlings, Matthias
AU - Kühn, Arno
AU - Dumitrescu, Roman
ID - 20307
T2 - Proceedings of the Hamburg International Conference of Logistics (HICL)
TI - Identification of socio-technical changes caused by Industry 4.0
VL - 29
ER -
TY - JOUR
AU - Albus, Vanessa
AU - Petermann, Hans-Bernhard
ID - 50694
JF - ZDPE
TI - Im Interview mit….
VL - 3
ER -
TY - JOUR
AB - Let D<0 be a fundamental discriminant and denote by E(D) the exponent of the ideal class group Cl(D) of K=ℚ(√D). Under the assumption that no Siegel zeros exist we compute all such D with E(D) dividing 8. We compute all D with |D| ≤ 3.1⋅10²⁰ such that E(D) ≤ 8.
AU - Elsenhans, Andreas-Stephan
AU - Klüners, Jürgen
AU - Nicolae, Florin
ID - 34842
IS - 3
JF - Acta Arithmetica
KW - Algebra and Number Theory
SN - 0065-1036
TI - Imaginary quadratic number fields with class groups of small exponent
VL - 193
ER -
TY - BOOK
AB - Durch seine immanente Kritik soziologischer Theorie reflektiert Christoph Haker Theorie als Praxis. Sein hierfür entwickelter heuristischer Bezugsrahmen ist die soziologische Differenz, in der sich die Theorien von ihrem Anderen - d.h. erstens von der Gesellschaft, zweitens von anderen Theorien und drittens reflexiv von sich selbst - unterscheiden. Das Ziel der Kritik ist ein praktischer Umgang mit der Multiparadigmatizität der Soziologie und die Öffnung ihrer Kontingenz: Theorien sollen auf diesem Weg ihre Geschlossenheit verlieren und ihre Selbstverständlichkeit einbüßen.
AU - Haker, Christoph
ID - 51257
SN - 2703-1276
TI - Immanente Kritik soziologischer Theorie
ER -
TY - JOUR
AU - Schmidt, Rebekka
ID - 49996
JF - #schuleDIGITAL. Friedrich Jahresheft XXXVIII
TI - Immer alles digital? Digitale Medien als Potenzial und Aufgabe für den Kunstunterricht
ER -
TY - JOUR
AB - AbstractThe value of models is well recognised in product and systems engineering. Modelling languages and diagrams are used to capture mental models and to handle model complexity. Literature research indicates that there are only very few approaches to utilise the potential of virtual and augmented reality for supporting tasks in model based (systems) engineering. The paper at hand contributes a new morphology of intuitive interaction for Immersive Abstraction as a holistic approach to extend that coverage. It presents a holistic framework to categorise solutions and future research directions.
AU - Gräßler, Iris
AU - Pottebaum, Jens
ID - 23468
JF - Proceedings of the Design Society: DESIGN Conference; 26. - 29. Okt. 2020
SN - 2633-7762
TI - Immersive Abstraction: A new Morphology of Intuitive Interaction with System Models
VL - Band 1
ER -
TY - JOUR
AU - Streiter, Martin
AU - Fischer, Tillmann G.
AU - Wiebeler, Christian
AU - Reichert, Sebastian
AU - Langenickel, Jörn
AU - Zeitler, Kirsten
AU - Deibel, Carsten
ID - 20496
JF - The Journal of Physical Chemistry C
KW - pc2-ressources
SN - 1932-7447
TI - Impact of Chlorine on the Internal Transition Rates and Excited States of the Thermally Delayed Activated Fluorescence Molecule 3CzClIPN
ER -
TY - JOUR
AU - Abdelsamie, Maged
AU - Xu, Junwei
AU - Bruening, Karsten
AU - Tassone, Christopher J.
AU - Steinrück, Hans-Georg
AU - Toney, Michael F.
ID - 23601
JF - Advanced Functional Materials
SN - 1616-301X
TI - Impact of Processing on Structural and Compositional Evolution in Mixed Metal Halide Perovskites during Film Formation
VL - 30
ER -
TY - BOOK
ED - Ehland, Christoph
ID - 35497
SN - 9789004426559
TI - Imperial Middlebrow
VL - Volume 7
ER -
TY - JOUR
AU - Breuer, Judith
AU - Vogelsang, Christoph
AU - Reinhold, Peter
ID - 35527
JF - PhyDid A - Physik und Didaktik in Schule und Hochschule
TI - Implementation und Nutzung von Unterrichtsmaterialien im schulischen Unterricht – Eine Bestandsaufnahme der mathematisch-naturwissenschaftlichen Fächer
ER -
TY - CONF
AU - Risse, L.
AU - Kullmer, G.
ID - 22143
T2 - DVM-Bericht 405, Arbeitskreis: Additiv gefertigte Bauteile und Strukturen, Deutscher Verband für Materialforschung und -prüfung e.V.
TI - Implementierung additiver Fertigungsverfahren in den chirurgischen Arbeitsablauf
VL - 405
ER -
TY - GEN
AU - Thiele, Simon
ID - 20820
TI - Implementing Machine Learning Functions as PYNQ FPGA Overlays
ER -
TY - JOUR
AU - Soleymani, Mohammad
AU - Santamaria, Ignacio
AU - Schreier, Peter J
ID - 40675
IS - 10
JF - IEEE Transactions on Vehicular Technology
TI - Improper Gaussian Signaling for the $K$-User MIMO Interference Channels With Hardware Impairments
VL - 69
ER -
TY - JOUR
AB - As a result of lightweight design, increased use is being made of high-strength steel and aluminium in car bodies. Self-piercing riveting is an established technique for joining these materials. The dissimilar properties of the two materials have led to a number of different rivet geometries in the past. Each rivet geometry fulfils the requirements of the materials within a limited range. In the present investigation, an improved rivet geometry is developed, which permits the reliable joining of two material combinations that could only be joined by two different rivet geometries up until now. Material combination 1 consists of high-strength steel on both sides, while material combination 2 comprises aluminium on the punch side and high-strength steel on the die side. The material flow and the stress and strain conditions prevailing during the joining process are analysed by means of numerical simulation. The rivet geometry is then improved step-by-step on the basis of this analysis. Finally, the improved rivet geometry is manufactured and the findings of the investigation are verified in experimental joining tests.
AU - Uhe, Benedikt
AU - Kuball, Clara-Maria
AU - Merklein, Marion
AU - Meschut, Gerson
ID - 19973
JF - Production Engineering
KW - Self-piercing riveting
KW - Joining technology
KW - Rivet geometry
KW - Multi-material design
KW - High-strength steel
KW - Aluminium
TI - Improvement of a rivet geometry for the self-piercing riveting of high-strength steel and multi-material joints
VL - 14
ER -
TY - JOUR
AU - Gräßler, Iris
AU - Scholle, Philipp
AU - Thiele, Henrik
ID - 23463
JF - Proceedings of the DESIGN 2020 16th International Design Conference; 26. - 29. Okt. 2020
TI - Improving scenario-technique by a semi-automatized consistency assessment based on pattern recognition by artificial neural networks
VL - 1
ER -
TY - JOUR
AU - Sonnenrein, G.
AU - Baumhögger, Elmar
AU - Elsner, A.
AU - Morbach, A.
AU - Neukötter, M.
AU - Paul, A.
AU - Vrabec, J.
ID - 17589
JF - International Journal of Refrigeration
SN - 0140-7007
TI - Improving the performance of household refrigerating appliances through the integration of phase change materials in the context of the new global refrigerator standard IEC 62552:2015
ER -
TY - JOUR
AB - The influence of latent heat storage elements on the cooling performance and the temperature rise time of household refrigerating appliances is studied experimentally in the context of the “new global refriger- ator standard”IEC 62552:2015. In addition to the daily energy consumption, this international standard- ization introduced performance tests for cooling capacity and temperature rise time. While the cooling capacity has long been anchored in various test procedures of consumer organizations, the temperature rise time, which has only been tested on freezers so far, will be a decisive factor in the future. Moreover, the need for so-called "smart appliances" that may balance power consumption is increasing since such devices may compensate the volatility of renewable energies and thus stabilize the power grid. Against this background, eight commercial household refrigerators and refrigerator-freezers are equipped with polymer-bound phase change materials (PCM) and their performance is determined under the new stan- dard test conditions. The results show that the introduction of PCM increases the cooling capacity by up to 33 % and also increases the temperature rise time by up to 145 %, without affecting power consump- tion, as compared to the unmodified refrigeration appliances.
AU - Sonnenrein, Gerrit
AU - Baumhögger, Elmar
AU - Elsner, Andreas
AU - Morbach, A.
AU - Neukötter, Moritz
AU - Paul, Andreas
AU - Vrabec, J.
ID - 21514
JF - International Journal of Refrigeration
SN - 0140-7007
TI - Improving the performance of household refrigerating appliances through the integration of phase change materials in the context of the new global refrigerator standard IEC 62552:2015
VL - 119
ER -
TY - BOOK
ED - Autsch, Sabiene
ED - Pickartz, Tim
ID - 49915
TI - Impulse 5. Texte und Bilder zur Kunstvermittlung: Go West! Kunst- und Ausstellungsszene New York 2019.
ER -
TY - GEN
AU - Ahrens, Stephan
ID - 44394
TI - In memoriam Sarah Maldoror
ER -
TY - JOUR
AB - Photovoltaics is one of the most promising and fastest-growing renewable energy technologies. Although the price-performance ratio of solar cells has improved significantly over recent years{,} further systematic investigations are needed to achieve higher performance and lower cost for future solar cells. In conjunction with experiments{,} computer simulations are powerful tools to investigate the thermodynamics and kinetics of solar cells. Over the last few years{,} we have developed and employed advanced computational techniques to gain a better understanding of solar cells based on copper indium gallium selenide (Cu(In{,}Ga)Se2). Furthermore{,} we have utilized state-of-the-art data-driven science and machine learning for the development of photovoltaic materials. In this Perspective{,} we review our results along with a survey of the field.
AU - Mirhosseini, S. Hossein
AU - Kormath Madam Raghupathy, Ramya
AU - Sahoo, Sudhir K.
AU - Wiebeler, Hendrik
AU - Chugh, Manjusha
AU - Kühne, Thomas
ID - 21112
JF - Phys. Chem. Chem. Phys.
TI - In silico investigation of Cu(In,Ga)Se2-based solar cells
VL - 22
ER -
TY - CHAP
AU - Scharlau, Ingrid
AU - Schreiber, Christine
ED - Geiß, Paul Georg
ED - Tulis-Oswald, Maria
ID - 31662
KW - Unterrichtsfach Psychologie
T2 - Psychologie unterrichten in Deutschland, Österreich und der Schweiz: Leitlinien und Grundlagen
TI - In Zeiten von p-hacking und fake science: Wissenschaftsorientierung als Herausforderung an die Psychologiedidaktik
ER -
TY - CONF
AU - Reinhold, Jannik
AU - Frank, Maximilian
AU - Koldewey, Christian
AU - Dumitrescu, Roman
AU - Buss, Eugen
ID - 18876
T2 - Proceedings of the ISPIM Connects Bangkok – Partnering for an Innovative Community
TI - In-depth Analysis of the Effects of Smart Services on Value Creation
ER -
TY - JOUR
AU - Kunnathully, Vinay S.
AU - Riedl, Thomas
AU - Trapp, Alexander
AU - Langer, Timo
AU - Reuter, Dirk
AU - Lindner, Jörg K.N.
ID - 17434
JF - Journal of Crystal Growth
SN - 0022-0248
TI - InAs heteroepitaxy on nanopillar-patterned GaAs (111)A
ER -
TY - JOUR
AU - Kunnathully, Vinay S.
AU - Riedl, Thomas
AU - Trapp, Alexander
AU - Langer, Timo
AU - Reuter, Dirk
AU - Lindner, Jörg
ID - 34091
JF - Journal of Crystal Growth
KW - Materials Chemistry
KW - Inorganic Chemistry
KW - Condensed Matter Physics
SN - 0022-0248
TI - InAs heteroepitaxy on nanopillar-patterned GaAs (111)A
VL - 537
ER -
TY - JOUR
AU - Heyser, Per
AU - Sartisson, Vadim
AU - Meschut, Gerson
AU - Droß, Marcel
AU - Dröder, Klaus
ID - 20235
JF - Materials Testing
SN - 0025-5300
TI - Increased load bearing capacity of mechanically joined FRP/metal joints using a pin structured auxiliary joining element
ER -
TY - CONF
AU - Dreiling, Dmitrij
AU - Itner, Dominik Thor
AU - Feldmann, Nadine
AU - Gravenkamp, Hauke
AU - Henning, Bernd
ID - 17089
TI - Increasing the sensitivity in the determination of material parameters by using arbitrary loads in ultrasonic transmission measurements
ER -
TY - CONF
AU - Knickenberg, Margarita
ID - 45052
TI - Individualisierung des Lernens im inklusiven Unterricht aus der Perspektive von Lehrkräften und Kindern.
ER -
TY - CONF
AU - Hellmich, Frank
AU - Schwab, Susanne
ID - 36236
TI - Individualisierung des Lernens im inklusiven Unterricht aus der Perspektive von Lehrkräften und Kindern. Symposium auf der 8. Tagung der Gesellschaft für Empirische Bildungsforschung (GEBF). Thema: „Bildung gestalten – Partizipation erreichen – Digitalisierung nutzen“
ER -
TY - CONF
AU - Lange, Sven
AU - Schroder, Dominik
AU - Hedayat, Christian
AU - Otto, Thomas
AU - Hilleringmann, Ulrich
ID - 39410
T2 - 2019 17th IEEE International New Circuits and Systems Conference (NEWCAS)
TI - Inductive Locating Method to Locate Miniaturized Wireless Sensors within Inhomogeneous Dielectrics
ER -
TY - JOUR
AB - A lower 24-h urine pH (24h-pH), i.e., a higher renal excretion of free protons, at a given acid load to the body, denotes a reduction in the kidney’s capacity for net acid excretion (NAE). There is increasing evidence, not only for patients with type 2 diabetes but also for healthy individuals, that higher body fatness or waist circumference (WC) has a negative impact on renal function to excrete acids (NAE). We hypothesized that adiposity-related inflammation molecules might mediate this relation between adiposity and renal acid excretion function. Twelve biomarkers of inflammation were measured in fasting blood samples from 162 adult participants (18–25 yr old) of the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study who had undergone anthropometric measurements and collected 24-h urine samples. Both Baron and Kenny’s (B&K’s) steps to test mediation and causal mediation analysis were conducted to examine the potential mediatory roles of biomarkers of inflammation in the WC-24-h pH relationship after strictly controlling for laboratory-measured NAE. In B&K’s mediation analysis, leptin, soluble intercellular adhesion molecule 1 (sICAM-1), and adiponectin significantly associated with the outcome 24-h pH and attenuated the WC-pH relation. In agreement herewith, causal mediation analysis estimated the “natural indirect effects” of WC on 24-h pH via leptin ( P = 0.01) and adiponectin ( P = 0.03) to be significant, with a trend for sICAM-1 ( P = 0.09). The calculated proportions mediated by leptin, adiponectin, and sICAM-1 were 64%, 23%, and 12%, respectively. Both mediation analyses identified an inflammatory cytokine (leptin) and an anti-inflammatory cytokine (adiponectin) along with sICAM-1 as being potentially involved in mediating adiposity-related influences on renal acid excretion capacity.
AU - Hua, Yifan
AU - Herder, Christian
AU - Kalhoff, Hermann
AU - Buyken, Anette
AU - Esche, Jonas
AU - Krupp, Danika
AU - Wudy, Stefan A.
AU - Remer, Thomas
ID - 27800
JF - American Journal of Physiology-Renal Physiology
SN - 1931-857X
TI - Inflammatory mediators in the adipo-renal axis: leptin, adiponectin, and soluble ICAM-1
ER -
TY - JOUR
AU - Knust, Steffen
AU - Kuhlmann, Andreas
AU - Orive, Alejandro G.
AU - de los Arcos de Pedro, Maria Teresa
AU - Grundmeier, Guido
ID - 22536
JF - Surface and Interface Analysis
SN - 0142-2421
TI - Influence of dielectric barrier plasma treatment of ZnMgAl alloy‐coated steel on the adsorption of organophosphonic acid monolayers
ER -
TY - GEN
AU - Tischendorf, Ricardo
AU - Schmid, Hans-Joachim
AU - Bieber, M.
AU - Reddemann , M.
AU - Kneer, R.
AU - Fröde, F.
AU - Grenga, T.
AU - Pitsch, H.
ID - 25062
TI - Influence of differing nozzle configurations on the final particle characteristics and particle structure evolution in spray flames
ER -
TY - JOUR
AU - Bürger, Julius
AU - Riedl, Thomas
AU - Lindner, Jörg K.N.
ID - 20892
JF - Ultramicroscopy
SN - 0304-3991
TI - Influence of lens aberrations, specimen thickness and tilt on differential phase contrast STEM images
ER -
TY - JOUR
AU - Bürger, Julius
AU - Riedl, Thomas
AU - Lindner, Jörg
ID - 34088
JF - Ultramicroscopy
KW - Instrumentation
KW - Atomic and Molecular Physics
KW - and Optics
KW - Electronic
KW - Optical and Magnetic Materials
SN - 0304-3991
TI - Influence of lens aberrations, specimen thickness and tilt on differential phase contrast STEM images
VL - 219
ER -
TY - CONF
AU - Schöppner, Volker
AU - Bialaschik, Max
ID - 24471
T2 - 73th Annual Assembly of the International Institute of Welding (IIW)
TI - Influence of Material Degradation on Weld Seam Quality in Hot Gas Welding of Polyamides
ER -
TY - JOUR
AU - Grydin, Olexandr
AU - Matzelt, Manuel
AU - Andreiev, Anatolii
AU - Frolov, Yaroslav
AU - Schaper, Mirko
ID - 23899
JF - Advanced Engineering Materials
SN - 1438-1656
TI - Influence of Microstructure in Near‐Surface Areas of Feedstocks on the Bond Strength of Roll Bonded Aluminum Clads
ER -
TY - CHAP
AU - Grydin, Olexandr
AU - Stolbchenko, Mykhailo
AU - Schaper, Mirko
ID - 24575
SN - 2367-1181
T2 - Light Metals 2020
TI - Influence of Nozzle Shape on Near-Surface Segregation Formation During Twin-Roll Casting of Aluminum Strips
ER -
TY - CONF
AU - Kummert, Chrstina
AU - Diekmann, Wolfgang
AU - Tews, Karina
AU - Schmid, Hans-Joachim
ID - 27106
T2 - 29th Annual International Solid Freeform Fabrication Symposium
TI - Influence of Part Microstructure on Mechanical Properties of PA6X Laser Sintered Specimens
ER -
TY - CONF
AU - Kummert, Christina
AU - Diekmann, Wolfgang
AU - Tews, Katrin
AU - Schmid, Hans-Joachim
ID - 22182
T2 - 29th Annual International Solid Freeform Fabrication Symposium
TI - Influence of Part Microstructure on Mechanicl Properties of PA6X Laser Sintered Specimens
VL - 29
ER -
TY - GEN
AB - Due to the trend towards lightweight design in car body development mechanical joining technologies become increasingly important. These techniques allow for the joining of dissimilar materials and thus enable multi-material design, while thermic joining methods reach their limits. Semi-tubular self-piercing riveting is an important mechanical joining technology. The rivet production, however, is costly and time-consuming, as the process consists of several process steps including the heat treatment and coating of the rivets in order to achieve an adequate strength and corrosion resistance. The use of high nitrogen steel as rivet material leads to the possibility of reducing process steps and hence increasing the efficiency of the process. However, the high tool loads being expected due to the high strain hardening of the material are a major challenge during the rivet production. Thus, there is a need for appropriate forming strategies, such as the manufacturing of the rivets at elevated temperatures. Prior investigations led to the conclusion that forming already at 200 °C results in a distinct reduction of the yield strength. To create a deeper understanding of the forming behaviour of high nitrogen steel at elevated temperatures, compression tests were conducted in a temperature range between room temperature and 200 °C. The determined true stress – true strain curves are the basis for the further process and tool design of the rivet production. Another key factor for the rivet manufacturing at elevated temperatures is the influence of the process temperature on the tribological conditions. For this reason, ring compression tests at room temperature and 200 °C are carried out. The friction factors are determined on the basis of calibration curves resulting from the numerical analysis of the ring compression process. The investigations indicate that the friction factor at 200 °C is significantly higher compared to room temperature. This essential fact has to be taken into account for the process and tool design for the rivet production using high nitrogen steel.
ED - Kuball, Clara-Maria
ED - Jung, R
ED - Uhe, Benedikt
ED - Meschut, Gerson
ED - Merklein, Marion
ID - 19974
KW - High nitrogen steel
KW - Self-piercing riveting
KW - Joining by forming
KW - Bulk forming
KW - Strain hardening
TI - Influence of the process temperature on the forming behaviour and the friction during bulk forming of high nitrogen steel
VL - 1
ER -