TY - CONF
AU - Itner, D.
AU - Gravenkamp, H.
AU - Dreiling, Dmitrij
AU - Feldmann, Nadine
AU - Henning, Bernd
ID - 40541
T2 - 14th WCCM-ECCOMAS Congress
TI - Simulation of Guided Waves in Cylinders Subject to Arbitrary Boundary Conditions Using the Scaled Boundary Finite Element Method
VL - 700
ER -
TY - JOUR
AU - Uppenkamp, Vera
AU - Höger, Christian
ID - 41427
IS - 2
JF - Theo-Web. Zeitschrift für Religionspädagogik
TI - "Wenn sich die Mitte auflöst...", ist das kein Verlust für die Religionspädagogik - ein bilanzierender Tagungsrückblick mit Augenzwinkern
VL - 20
ER -
TY - GEN
AU - Uppenkamp, Vera
ID - 41425
T2 - Das wissenschaftlich-religionspädagogische Lexikon im Internet www.wirelex.de
TI - Art. Mädchen/Frauen
ER -
TY - THES
AU - Olma, Simon
ID - 42070
SN - 9783947647231
TI - Systemtheorie von Hardware-in-the-Loop-Simulationen mit Anwendung auf einem Fahrzeugachsprüfstand mit parallelkinematischem Lastsimulator
VL - 404
ER -
TY - THES
AU - Lankeit, Christopher
ID - 42069
TI - Systematik zur Evolution technischer Anforderungen
ER -
TY - BOOK
AU - Eckel, Julia
ID - 42250
SN - 978-3-8394-5320-9
TI - Das Audioviduum. Eine Theoriegeschichte des Menschenmotivs in audiovisuellen Medien
ER -
TY - CHAP
AU - Fuchs, Christian
ED - Fuchs, Christian
ED - Unterberger, Klaus
ID - 38153
T2 - The Public Service Media and Public Service Internet Manifesto
TI - The Public Service Media and Public Service Internet Utopias Survey Report
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38143
IS - 15
JF - Information, Communication and Society
TI - History and Class Consciousness 2.0: Georg Lukács in the Age of Digital Capitalism and Big Data
VL - 24
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38146
IS - 1
JF - tripleC: Communication, Capitalism & Critique
TI - Engels@200: Friedrich Engels and Digital Capitalism. How Relevant Are Engels’s Works 200 Years After His Birth?
VL - 19
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38145
IS - 1
JF - tripleC: Communication, Capitalism & Critique
TI - Engels@200: Friedrich Engels in the Age of Digital Capitalism. Introduction
VL - 19
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38147
IS - 7-8
JF - Critical Sociology
TI - Cornel West and Marxist Humanism
VL - 47
ER -
TY - BOOK
ED - Fuchs, Christian
ED - Unterberger, Klaus
ID - 38133
TI - The Public Service Media and Public Service Internet Manifesto
ER -
TY - CHAP
AU - Alessandro, D'Arma
AU - Fuchs, Christian
AU - Horowitz, Minna
AU - Unterberger, Klaus
ED - Fuchs, Christian
ED - Unterberger, Klaus
ID - 38152
T2 - The Public Service Media and Public Service Internet Manifesto
TI - The Future of Public Service Media and the Internet
ER -
TY - CHAP
AU - Fuchs, Christian
AU - Unterberger, Klaus
ED - Fuchs, Christian
ED - Unterberger, Klaus
ID - 38154
T2 - The Public Service Media and Public Service Internet Manifesto
TI - Introduction
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38148
IS - 1
JF - Westminster Papers in Communication and Culture
TI - The Digital Commons and the Digital Public Sphere: How to Advance Digital Democracy Today
VL - 16
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38157
IS - 1
JF - tripleC: Communication, Capitalism & Critique
TI - How Did Donald Trump Incite a Coup Attempt?
VL - 19
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 38149
IS - 4
JF - Journal of Media Ethics
TI - Foundations of Communication/Media/Digital (In)Justice
VL - 36
ER -
TY - GEN
AU - Fuchs, Christian
ID - 38156
T2 - The Conversation
TI - Channel 4: Rather Than Privatising Public Service Media We Should Be Expanding It Online
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 42483
IS - 2
JF - tripleC: Communication, Capitalism & Critique
TI - Preface: Manfred Knoche’s Critique of the Political Economy of the Media and Communication [Preface to the article “Media Concentration” by Manfred Knoche]
VL - 19
ER -
TY - JOUR
AB - Lithium niobate (LiNbO3), a material frequently used in optical applications, hosts different kinds of polarons that significantly affect many of its physical properties. In this study, a variety of electron polarons, namely free, bound, and bipolarons, are analyzed using first-principles calculations. We perform a full structural optimization based on density-functional theory for selected intrinsic defects with special attention to the role of symmetry-breaking distortions that lower the total energy. The cations hosting the various polarons relax to a different degree, with a larger relaxation corresponding to a larger gap between the defect level and the conduction-band edge. The projected density of states reveals that the polaron states are formerly empty Nb 4d states lowered into the band gap. Optical absorption spectra are derived within the independent-particle approximation, corrected by the GW approximation that yields a wider band gap and by including excitonic effects within the Bethe-Salpeter equation. Comparing the calculated spectra with the density of states, we find that the defect peak observed in the optical absorption stems from transitions between the defect level and a continuum of empty Nb 4d states. Signatures of polarons are further analyzed in the reflectivity and other experimentally measurable optical coefficients.
AU - Schmidt, Falko
AU - Kozub, Agnieszka L.
AU - Gerstmann, Uwe
AU - Schmidt, Wolf Gero
AU - Schindlmayr, Arno
ID - 21946
JF - Crystals
TI - Electron polarons in lithium niobate: Charge localization, lattice deformation, and optical response
VL - 11
ER -
TY - JOUR
AB - Tailor-made ordered mesoporous materials bear great potential in numerous fields of application where large interfaces are required. However, the inherent surfacechemical properties of conventional materials, such as silica, carbon or organosilica, poses some limitations with respect to their application. Surface manipulation by functionalization with chemically more reactive groups is one way to improve materials for their desired purpose. Another approach is the design of high surface-area composite materials. The surface manipulation, either by functionalization or by introducing guest species, can be performed selectively. This means that when several distinct, i.e. , hierarchical, types of surfaces or pore systems exist in a material, each of them may be chosen for manipulation. Several strategies can be identified to achieve this goal. Molecules or molecule assemblies can be utilized to temporarily protect pores or surfaces (soft protection), while manipulation occurs at the accessible sites. This approach is a recurring motive in this review and can also be applied to rigid template matrices (hard protection). Furthermore, the size of functionalization agents (size protection) and their reactivity/diffusion (kinetic protection) into the pores can also be utilized to achieve selectivity. In addition, challenges in the synthesis and characterization of selectively manipulated ordered mesoporous materials are discussed.
AU - Tiemann, Michael
AU - Weinberger, Christian
ID - 25893
JF - Advanced Materials Interfaces
SN - 2196-7350
TI - Selective Modification of Hierarchical Pores and Surfaces in Nanoporous Materials
ER -
TY - JOUR
AU - Fuchs, Christian
ID - 41431
IS - 1
JF - tripleC: Communication, Capitalism & Critique
TI - Engels@200: Friedrich Engels in the Age of Digital Capitalism
VL - 19
ER -
TY - JOUR
AU - Möhring, Julia
AU - Krumhöfner, Anika
AU - Gräfin von Plettenberg, Elisabeth Gudila Sophia Ida Maria
ID - 43016
JF - -
TI - Bewegungsförderung in Ganztagsschulen
ER -
TY - GEN
AU - Leineweber, Jonas
ID - 33210
TI - Veranstaltungsbericht: Immaterielles Kulturerbe in Nordrhein-Westfalen – Steigerlied und Trinkhallenkultur im Ruhrgebiet erhalten Auszeichnung anlässlich der Neuaufnahmen in das nordrhein-westfälische Landesinventar
ER -
TY - GEN
AU - Leineweber, Jonas
ID - 33209
TI - Tagungsbericht: Immaterielles Kulturerbe und regionale Identität. Gesellschaftliche Repräsentation und Partizipation im Schützenwesen
ER -
TY - JOUR
AB - We perform a theoretical analysis of the structural and electronic properties of sodium potassium niobate K1-xNaxNbO3 in the orthorhombic room-temperature phase, based on density-functional theory in combination with the supercell approach. Our results for x=0 and x=0.5 are in very good agreement with experimental measurements and establish that the lattice parameters decrease linearly with increasing Na contents, disproving earlier theoretical studies based on the virtual-crystal approximation that claimed a highly nonlinear behavior with a significant structural distortion and volume reduction in K0.5Na0.5NbO3 compared to both end members of the solid solution. Furthermore, we find that the electronic band gap varies very little between x=0 and x=0.5, reflecting the small changes in the lattice parameters.
AU - Bidaraguppe Ramesh, Nithin
AU - Schmidt, Falko
AU - Schindlmayr, Arno
ID - 22960
IS - 8
JF - The European Physical Journal B
SN - 1434-6028
TI - Lattice parameters and electronic band gap of orthorhombic potassium sodium niobate K0.5Na0.5NbO3 from density-functional theory
VL - 94
ER -
TY - JOUR
AU - Friedrich, Christoph
AU - Blügel, Stefan
AU - Schindlmayr, Arno
ID - 22761
IS - 3
JF - Physical Review B
SN - 2469-9950
TI - Erratum: Efficient implementation of the GW approximation within the all-electron FLAPW method [Phys. Rev. B 81, 125102 (2010)]
VL - 104
ER -
TY - JOUR
AB - Employing the ultrafast control of electronic states of a semiconductor quantum dot in a cavity, we introduce an approach to achieve on-demand emission of single photons with almost perfect indistinguishability and photon pairs with near ideal entanglement. Our scheme is based on optical excitation off resonant to a cavity mode followed by ultrafast control of the electronic states using the time-dependent quantum-confined Stark effect, which then allows for cavity-resonant emission. Our theoretical analysis considers cavity-loss mechanisms, the Stark effect, and phonon-induced dephasing, allowing realistic predictions for finite temperatures.
AU - Bauch, David
AU - Heinze, Dirk Florian
AU - Förstner, Jens
AU - Jöns, Klaus
AU - Schumacher, Stefan
ID - 23816
JF - Physical Review B
KW - tet_topic_qd
SN - 2469-9950
TI - Ultrafast electric control of cavity mediated single-photon and photon-pair generation with semiconductor quantum dots
VL - 104
ER -
TY - JOUR
AB - Density-functional theory within a Berry-phase formulation of the dynamical polarization is used to determine the second-order susceptibility χ(2) of lithium niobate (LiNbO3). Defect trapped polarons and bipolarons are found to strongly enhance the nonlinear susceptibility of the material, in particular if localized at NbV–VLi defect pairs. This is essentially a consequence of the polaronic excitation resulting in relaxation-induced gap states. The occupation of these levels leads to strongly enhanced χ(2) coefficients and allows for the spatial and transient modification of the second-harmonic generation of macroscopic samples.
AU - Kozub, Agnieszka L.
AU - Schindlmayr, Arno
AU - Gerstmann, Uwe
AU - Schmidt, Wolf Gero
ID - 23418
JF - Physical Review B
SN - 2469-9950
TI - Polaronic enhancement of second-harmonic generation in lithium niobate
VL - 104
ER -
TY - JOUR
AU - Martin, Sven
AU - Tröster, Thomas
ID - 24548
JF - ESAFORM 2021
TI - Joint point loadings in car bodies – the influence of manufacturing tolerances and scatter in material properties
ER -
TY - CONF
AB - One of the main objectives of production engineering is to reproducibly manufacture (complex) defect-free parts. To achieve this, it is necessary to employ an appropriate process or tool design. While this will generally prove successful, it cannot, however, offset stochastic defects with local variations in material properties. Closed-loop process control represents a promising approach for a solution in this context. The state of the art involves using this approach to control geometric parameters such as a length. So far, no research or applications have been conducted with closed-loop control for microstructure and product properties. In the project on which this paper is based, the local martensite content of parts is to be adjusted in a highly precise and reproducible manner. The forming process employed is a special, property-controlled flow-forming process. A model-based controller is thus to generate corresponding correction values for the tool-path geometry and tool-path velocity on the basis of online martensite content measurements. For the controller model, it is planned to use a special process or microstructure (correlation) model. The planned paper not only describes the experimental setup but also presents results of initial experimental investigations for subsequent use in the closed-loop control of α’-martensite content during flow-forming.
AU - Arian, Bahman
AU - Homberg, Werner
AU - Riepold, Markus
AU - Trächtler, Ansgar
AU - Rozo Vasquez, Julian
AU - Walther, Frank
ID - 23465
KW - Flow-forming
KW - Spinning
KW - Process Strategy
KW - Martensite Content
KW - Property Control
KW - Micromagnetic Measurement
KW - Metastable Austenitic Stainless Steel
SN - 978-2-87019-302-0
TI - Forming of metastable austenitic stainless steel tubes with axially graded martensite content by flow-forming
ER -
TY - JOUR
AB - Multiprofessionelle Teams sind notwendiger Bestandteil inklusiver Schulen. Die Verteilung von Aufgaben, welche über die Zusammenarbeit von allgemeinen und sonderpädagogischen Lehrkräften im Unterricht hinausgehen, wurde bislang jedoch selten systematisch untersucht. Im Beitrag werden deskriptive Befunde aus dem Projekt BiFoKi (Bielefelder Fortbildungskonzept zur Kooperation in inklusiven Schulen) zu den Zuständigkeiten von allgemeinen (N = 170) und sonderpädagogischen Lehrkräften (N = 24) sowie Schulsozialarbeiterinnen (N = 11) an inklusiven Sekundar- und Gesamtschulen präsentiert. Sie deuten auf eine Persistenz traditioneller Rollenmuster und Aufgabenverteilungen hin. Bei den befragten sonderpädagogischen Lehrkräften können zwei unterschiedliche Rollenmuster herausgearbeitet werden. Die Schulsozialarbeiterinnen weisen ein enges Arbeitsfeld mit einem Fokus auf Eltern-Schule-Kooperation auf.
AU - Neumann, Phillip
AU - Grüter, Sandra
AU - Eckel, Lisa
AU - Lütje-Klose, Birgit
AU - Wild, Elke
AU - Gorges, Julia
ID - 34484
IS - 4
JF - Zeitschrift für Heilpädagogik
KW - Inklusion
KW - Sonderpädagogik
KW - Sekundarstufe
KW - Gesamtschulen
KW - Kooperation
KW - Schulsozialarbeit
KW - BiFoKi
SN - 0513-9066
TI - Aufgaben und Zuständigkeiten von allgemeinen und sonderpädagogischen Lehrkräften sowie Fachkräften der Schulsozialarbeit in inklusiven Schulen der Sekundarstufe I. Erste Ergebnisse aus dem BiFoKi-Projekt
VL - 73
ER -
TY - CONF
AB - Challenges of the development of mechatronic systems and corresponding production systems have increased steadily. Changes are primarily due to increased product complexity and the connection to the internet of things and services, enabling Cyber-Physical Systems (CPS) and Cyber-Physical Production Systems (CPPS). Major innovations of the revised VDI guideline 2206 for developing mechatronic systems are systems thinking as a core element and six checkpoints for structuring deliverables along the V-Model. These checkpoints serve for orientation in result progress and thus enable a structured and complete development process. However, tasks and checkpoints of the new guideline focus on the product development itself without integrating the development of related CPPS, enabling optimization simultaneously to system development. Implications are derived by a three-step analysis. The paper at hand contributes fundamental extensions of the checkpoint questions regarding integrated CPPS development. These questions provide methodical support for system developers of CPPS for CPS by enabling the project manager to check the status, schedule further development steps and evaluate the maturity of the whole, integrated development.
AU - Gräßler, Iris
AU - Wiechel, Dominik
AU - Roesmann, Daniel
AU - Thiele, Henrik
ID - 24080
KW - Cyber-Physical Production System (CPPS)
KW - V-Model
KW - Product System Development
KW - Integrated Development
KW - VDI 2206
SN - 2212-8271
T2 - Procedia CIRP
TI - V-model based development of cyber-physical systems and cyber-physical production systems
ER -
TY - CONF
AB - The battle of developing hardware Trojans and corresponding countermeasures has taken adversaries towards ingenious ways of compromising hardware designs by circumventing even advanced testing and verification methods. Besides conventional methods of inserting Trojans into a design by a malicious entity, the design flow for field-programmable gate arrays (FPGAs) can also be surreptitiously compromised to assist the attacker to perform a successful malfunctioning or information leakage attack. The advanced stealthy malicious look-up-table (LUT) attack activates a Trojan only when generating the FPGA bitstream and can thus not be detected by register transfer and gate level testing and verification. However, also this attack was recently revealed by a bitstream-level proof-carrying hardware (PCH) approach. In this paper, we present a novel attack that leverages malicious routing of the inserted Trojan circuit to acquire a dormant state even in the generated and transmitted bitstream. The Trojan's payload is connected to primary inputs/outputs of the FPGA via a programmable interconnect point (PIP). The Trojan is detached from inputs/outputs during place-and-route and re-connected only when the FPGA is being programmed, thus activating the Trojan circuit without any need for a trigger logic. Since the Trojan is injected in a post-synthesis step and remains unconnected in the bitstream, the presented attack can currently neither be prevented by conventional testing and verification methods nor by recent bitstream-level verification techniques.
AU - Ahmed, Qazi Arbab
AU - Wiersema, Tobias
AU - Platzner, Marco
ID - 20681
T2 - 2021 Design, Automation & Test in Europe Conference & Exhibition (DATE)
TI - Malicious Routing: Circumventing Bitstream-level Verification for FPGAs
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
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 - 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 - 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 - 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 - 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 - 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 - 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 - CONF
AU - Kenter, Tobias
AU - Shambhu, Adesh
AU - Faghih-Naini, Sara
AU - Aizinger, Vadym
ID - 46194
T2 - Proceedings of the Platform for Advanced Scientific Computing Conference
TI - Algorithm-hardware co-design of a discontinuous Galerkin shallow-water model for a dataflow architecture on FPGA
ER -
TY - BOOK
AB - Trotz massiver Förderungen für die Digitalisierung ist die Präsenzlehre noch immer der Standard an deutschen Hochschulen. Aufgrund des Physical Distancing im Zuge der Corona-Pandemie musste sie jedoch kurzfristig fast vollständig digitalisiert werden. Die Beiträge des Bandes bieten einen multiperspektivischen Zugang zu den damit verbundenen Herausforderungen und beleuchten, wie die verschiedenen Akteur*innen die Umstellung auf digitale Lehr- und Lernformate umgesetzt und erlebt haben. Durch die Zusammenführung der verschiedenen Sichtweisen können die Bedarfe und Wünsche der einzelnen Akteursgruppen zusammengebracht und bei der nachhaltigen Weiterentwicklung der Hochschullehre besser berücksichtigt werden.
ED - Neiske, Iris
ED - Osthushenrich, Judith
ED - Schaper, Niclas
ED - Trier, Ulrike
ED - Vöing, Nerea
ID - 46613
SN - 2749-7623
TI - Hochschule auf Abstand
ER -
TY - CONF
AB -
Predictive Maintenance as a desirable maintenance strategy in industrial applications relies on suitable condition monitoring solutions to reduce costs and risks of the monitored technical systems. In general, those solutions utilize model-based or data-driven methods to diagnose the current state or predict future states of monitored technical systems. However, both methods have their advantages and drawbacks. Combining both methods can improve uncertainty consideration and accuracy. Different combination approaches of those hybrid methods exist to exploit synergy effects. The choice of an appropriate approach depends on different requirements and the goal behind the selection of a hybrid approach.
In this work, the hybrid approach for estimating remaining useful lifetime takes potential uncertainties into account. Therefore, a data-driven estimation of new measurements is integrated within a model-based method. To consider uncertainties within the system, a differentiation between different system behavior is realized throughout diverse states of degradation.
The developed hybrid prediction approach bases on a particle filtering method combined with a machine learning method, to estimate the remaining useful lifetime of technical systems. Particle filtering as a Monte Carlo simulation technique is suitable to map and propagate uncertainties. Moreover, it is a state-of-the-art model-based method for predicting remaining useful lifetime of technical systems. To integrate uncertainties a multi-model particle filtering approach is employed. In general, resampling as a part of the particle filtering approach has the potential to lead to an accurate prediction. However, in the case where no future measurements are available, it may increase the uncertainty of the prediction. By estimating new measurements, those uncertainties are reduced within the data-driven part of the approach. Hence, both parts of the hybrid approach strive to account for and reduce uncertainties.
Rubber-metal-elements are employed as a use-case to evaluate the developed approach. Rubber-metal-elements, which are used to isolate vibrations in various systems, such as railways, trucks and wind turbines, show various uncertainties in their behavior and their degradation. Those uncertainties are caused by diverse inner and outer factors, such as manufacturing influences and operating conditions. By expert knowledge the influences are described, analyzed and if possible reduced. However, the remaining uncertainties are considered within the hybrid prediction method. Relative temperature is the selected measurand to describe the element’s degradation. In lifetime tests, it is measured as the difference between the element’s temperature and the ambient temperature. Thereby, the influence of the ambient temperature on the element’s temperature is taken into account. Those elements show three typical states of degradation that are identified within the temperature measurements. Depending on the particular state of degradation a new measurement is estimated within the hybrid approach to reduce potential uncertainties.
Finally, the performance of the developed hybrid method is compared to a model-based method for estimating the remaining useful lifetime of the same elements. Suitable performance indices are implemented to underline the differences between the results.
AU - Bender, Amelie
AU - Sextro, Walter
ED - Do, Phuc
ED - King, Steve
ED - Fink, Olga
ID - 22724
IS - 1
KW - Hybrid prediction method
KW - Multi-model particle filtering
KW - Uncertainty quantification
KW - RUL estimation
T2 - Proceedings of the European Conference of the PHM Society 2021
TI - Hybrid Prediction Method for Remaining Useful Lifetime Estimation Considering Uncertainties
VL - 6
ER -
TY - CONF
AB - Several methods, including order analysis, wavelet analysis and empirical mode decomposition have been proposed and successfully employed for the health state estimation of technical systems operating under varying conditions. However, where information such as the speed of rotating machinery, component specifications or other domain-specific information is unavailable, such methods are often infeasible. Thus, this paper investigates the application of classical time-domain features, features from the medical field and novel features from the highly comparative time-series analysis (HCTSA) package, for the health state estimation of rotating machinery operating under varying conditions. Furthermore, several feature selection methods are investigated to identify features as viable health indicators for the diagnostics and prognostics of technical systems. As a case study, the presented methods are evaluated on real-world and experimentally acquired vibration data of bearings operating under varying speed. The results show that the selected features can successfully be employed as health indicators for technical systems operating under varying conditions.
AU - Aimiyekagbon, Osarenren Kennedy
AU - Bender, Amelie
AU - Sextro, Walter
ID - 22507
KW - Wind turbine diagnostics
KW - bearing diagnostics
KW - non-stationary operating conditions
KW - varying operating conditions
KW - feature extraction
KW - feature selection
KW - fault detection
KW - failure detection
T2 - Proceedings of the Seventeenth International Conference on Condition Monitoring and Asset Management (CM 2021)
TI - On the applicability of time series features as health indicators for technical systems operating under varying conditions
ER -
TY - CONF
AB - In the industry 4.0 era, there is a growing need to transform unstructured data acquired by a multitude of sources into information and subsequently into knowledge to improve the quality of manufactured products, to boost production, for predictive maintenance, etc. Data-driven approaches, such as machine learning techniques, are typically employed to model the underlying relationship from data. However, an increase in model accuracy with state-of-the-art methods, such as deep convolutional neural networks, results in less interpretability and transparency. Due to the ease of implementation, interpretation and transparency to both domain experts and non-experts, a rule-based method is proposed in this paper, for prognostics and health management (PHM) and specifically for diagnostics. The proposed method utilizes the most relevant sensor signals acquired via feature extraction and selection techniques and expert knowledge. As a case study, the presented method is evaluated on data from a real-world quality control set-up provided by the European prognostics and health management society (PHME) at the conference’s 2021 data challenge. With the proposed method, our team took the third place, capable of successfully diagnosing different fault modes, irrespective of varying conditions.
AU - Aimiyekagbon, Osarenren Kennedy
AU - Muth, Lars
AU - Wohlleben, Meike Claudia
AU - Bender, Amelie
AU - Sextro, Walter
ED - Do, Phuc
ED - King, Steve
ED - Fink, Olga
ID - 27111
IS - 1
KW - PHME 2021
KW - Feature Selection Classification
KW - Feature Selection Clustering
KW - Interpretable Model
KW - Transparent Model
KW - Industry 4.0
KW - Real-World Diagnostics
KW - Quality Control
KW - Predictive Maintenance
T2 - Proceedings of the European Conference of the PHM Society 2021
TI - Rule-based Diagnostics of a Production Line
VL - 6
ER -
TY - JOUR
AU - Alhaddad, Samer
AU - Förstner, Jens
AU - Groth, Stefan
AU - Grünewald, Daniel
AU - Grynko, Yevgen
AU - Hannig, Frank
AU - Kenter, Tobias
AU - Pfreundt, Franz‐Josef
AU - Plessl, Christian
AU - Schotte, Merlind
AU - Steinke, Thomas
AU - Teich, Jürgen
AU - Weiser, Martin
AU - Wende, Florian
ID - 24788
JF - Concurrency and Computation: Practice and Experience
KW - tet_topic_hpc
SN - 1532-0626
TI - The HighPerMeshes framework for numerical algorithms on unstructured grids
ER -
TY - GEN
AU - Lammer, Christina
ID - 30961
TI - Andrea Karimé: Sterne im Kopf und ein unglaublicher Plan. Köln: Peter Hammer Verlag 2021
ER -
TY - JOUR
AB - AbstractQuantum well (QW) heterostructures have been extensively used for the realization of a wide range of optical and electronic devices. Exploiting their potential for further improvement and development requires a fundamental understanding of their electronic structure. So far, the most commonly used experimental techniques for this purpose have been all-optical spectroscopy methods that, however, are generally averaging in momentum space. Additional information can be gained by angle-resolved photoelectron spectroscopy (ARPES), which measures the electronic structure with momentum resolution. Here we report on the use of extremely low-energy ARPES (photon energy ~ 7 eV) to increase depth sensitivity and access buried QW states, located at 3 nm and 6 nm below the surface of cubic-GaN/AlN and GaAs/AlGaAs heterostructures, respectively. We find that the QW states in cubic-GaN/AlN can indeed be observed, but not their energy dispersion, because of the high surface roughness. The GaAs/AlGaAs QW states, on the other hand, are buried too deep to be detected by extremely low-energy ARPES. Since the sample surface is much flatter, the ARPES spectra of the GaAs/AlGaAs show distinct features in momentum space, which can be reconducted to the band structure of the topmost surface layer of the QW structure. Our results provide important information about the samples’ properties required to perform extremely low-energy ARPES experiments on electronic states buried in semiconductor heterostructures.
AU - Hajlaoui, Mahdi
AU - Ponzoni, Stefano
AU - Deppe, Michael
AU - Henksmeier, Tobias
AU - As, Donat Josef
AU - Reuter, Dirk
AU - Zentgraf, Thomas
AU - Springholz, Gunther
AU - Schneider, Claus Michael
AU - Cramm, Stefan
AU - Cinchetti, Mirko
ID - 25227
JF - Scientific Reports
SN - 2045-2322
TI - Extremely low-energy ARPES of quantum well states in cubic-GaN/AlN and GaAs/AlGaAs heterostructures
VL - 11
ER -
TY - CONF
AB - Unsupervised blind source separation methods do not require a training phase
and thus cannot suffer from a train-test mismatch, which is a common concern in
neural network based source separation. The unsupervised techniques can be
categorized in two classes, those building upon the sparsity of speech in the
Short-Time Fourier transform domain and those exploiting non-Gaussianity or
non-stationarity of the source signals. In this contribution, spatial mixture
models which fall in the first category and independent vector analysis (IVA)
as a representative of the second category are compared w.r.t. their separation
performance and the performance of a downstream speech recognizer on a
reverberant dataset of reasonable size. Furthermore, we introduce a serial
concatenation of the two, where the result of the mixture model serves as
initialization of IVA, which achieves significantly better WER performance than
each algorithm individually and even approaches the performance of a much more
complex neural network based technique.
AU - Boeddeker, Christoph
AU - Rautenberg, Frederik
AU - Haeb-Umbach, Reinhold
ID - 44843
T2 - ITG Conference on Speech Communication
TI - A Comparison and Combination of Unsupervised Blind Source Separation Techniques
ER -
TY - CONF
AU - Boeddeker, Christoph
AU - Zhang, Wangyou
AU - Nakatani, Tomohiro
AU - Kinoshita, Keisuke
AU - Ochiai, Tsubasa
AU - Delcroix, Marc
AU - Kamo, Naoyuki
AU - Qian, Yanmin
AU - Haeb-Umbach, Reinhold
ID - 28259
T2 - ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
TI - Convolutive Transfer Function Invariant SDR Training Criteria for Multi-Channel Reverberant Speech Separation
ER -
TY - CONF
AU - Schmalenstroeer, Joerg
AU - Heitkaemper, Jens
AU - Ullmann, Joerg
AU - Haeb-Umbach, Reinhold
ID - 23998
T2 - 29th European Signal Processing Conference (EUSIPCO)
TI - Open Range Pitch Tracking for Carrier Frequency Difference Estimation from HF Transmitted Speech
ER -
TY - GEN
AU - Hartung, Olaf
ID - 48787
T2 - H-Soz-Kult
TI - Rezension von: Jörg van Norden, Thomas Must, Lars Deile, Peter Riedel, Susan Krause und Wanda Schürenberg (Hgg.): Geschichtsdidaktische Grundbegriffe. Ein Bilderbuch für Studium, Lehre und Beruf. Hannover 2020
ER -
TY - JOUR
AB - Due to the ad hoc nature of wireless acoustic sensor networks, the position of the sensor nodes is typically unknown. This contribution proposes a technique to estimate the position and orientation of the sensor nodes from the recorded speech signals. The method assumes that a node comprises a microphone array with synchronously sampled microphones rather than a single microphone, but does not require the sampling clocks of the nodes to be synchronized. From the observed audio signals, the distances between the acoustic sources and arrays, as well as the directions of arrival, are estimated. They serve as input to a non-linear least squares problem, from which both the sensor nodes’ positions and orientations, as well as the source positions, are alternatingly estimated in an iterative process. Given one set of unknowns, i.e., either the source positions or the sensor nodes’ geometry, the other set of unknowns can be computed in closed-form. The proposed approach is computationally efficient and the first one, which employs both distance and directional information for geometry calibration in a common cost function. Since both distance and direction of arrival measurements suffer from outliers, e.g., caused by strong reflections of the sound waves on the surfaces of the room, we introduce measures to deemphasize or remove unreliable measurements. Additionally, we discuss modifications of our previously proposed deep neural network-based acoustic distance estimator, to account not only for omnidirectional sources but also for directional sources. Simulation results show good positioning accuracy and compare very favorably with alternative approaches from the literature.
AU - Gburrek, Tobias
AU - Schmalenstroeer, Joerg
AU - Haeb-Umbach, Reinhold
ID - 22528
JF - EURASIP Journal on Audio, Speech, and Music Processing
SN - 1687-4722
TI - Geometry calibration in wireless acoustic sensor networks utilizing DoA and distance information
ER -
TY - CONF
AU - Gburrek, Tobias
AU - Schmalenstroeer, Joerg
AU - Haeb-Umbach, Reinhold
ID - 23994
T2 - ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
TI - Iterative Geometry Calibration from Distance Estimates for Wireless Acoustic Sensor Networks
ER -
TY - CONF
AU - Gburrek, Tobias
AU - Schmalenstroeer, Joerg
AU - Haeb-Umbach, Reinhold
ID - 23999
T2 - Speech Communication; 14th ITG-Symposium
TI - On Source-Microphone Distance Estimation Using Convolutional Recurrent Neural Networks
ER -
TY - CONF
AU - Chinaev, Aleksej
AU - Enzner, Gerald
AU - Gburrek, Tobias
AU - Schmalenstroeer, Joerg
ID - 23997
T2 - 29th European Signal Processing Conference (EUSIPCO)
TI - Online Estimation of Sampling Rate Offsets in Wireless Acoustic Sensor Networks with Packet Loss
ER -
TY - GEN
AU - Moritz, Tilman
ID - 49017
IS - 10
T2 - sehepunkte
TI - A. Seidler, I. Monok (Hgg.): Reformation und Bücher. Zentren der Ideen – Zentren der Buchproduktion. Wiesbaden 2020
VL - 21
ER -
TY - CONF
AB - In this work we address disentanglement of style and content in speech signals. We propose a fully convolutional variational autoencoder employing two encoders: a content encoder and a style encoder. To foster disentanglement, we propose adversarial contrastive predictive coding. This new disentanglement method does neither need parallel data nor any supervision. We show that the proposed technique is capable of separating speaker and content traits into the two different representations and show competitive speaker-content disentanglement performance compared to other unsupervised approaches. We further demonstrate an increased robustness of the content representation against a train-test mismatch compared to spectral features, when used for phone recognition.
AU - Ebbers, Janek
AU - Kuhlmann, Michael
AU - Cord-Landwehr, Tobias
AU - Haeb-Umbach, Reinhold
ID - 29304
T2 - Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
TI - Contrastive Predictive Coding Supported Factorized Variational Autoencoder for Unsupervised Learning of Disentangled Speech Representations
ER -
TY - CONF
AB - The first order optimality conditions of optimal control problems (OCPs) can
be regarded as boundary value problems for Hamiltonian systems. Variational or
symplectic discretisation methods are classically known for their excellent
long term behaviour. As boundary value problems are posed on intervals of
fixed, moderate length, it is not immediately clear whether methods can profit
from structure preservation in this context. When parameters are present,
solutions can undergo bifurcations, for instance, two solutions can merge and
annihilate one another as parameters are varied. We will show that generic
bifurcations of an OCP are preserved under discretisation when the OCP is
either directly discretised to a discrete OCP (direct method) or translated
into a Hamiltonian boundary value problem using first order necessary
conditions of optimality which is then solved using a symplectic integrator
(indirect method). Moreover, certain bifurcations break when a non-symplectic
scheme is used. The general phenomenon is illustrated on the example of a cut
locus of an ellipsoid.
AU - Offen, Christian
AU - Ober-Blöbaum, Sina
ID - 22894
KW - optimal control
KW - catastrophe theory
KW - bifurcations
KW - variational methods
KW - symplectic integrators
SN - 2405-8963
TI - Bifurcation preserving discretisations of optimal control problems
VL - 54(19)
ER -
TY - JOUR
AB - In the last two decades, variably doped strontium barium niobate (SBN) has attracted a lot of scientific interest mainly due to its specific non-linear optical response. Comparably, the parental compound, i.e., undoped SBN, appears to be less studied so far. Here, two different cuts of single-crystalline nominally pure strontium barium niobate in the composition Sr0.61Ba0.39Nb2O6 (SBN61) are comprehensively studied and analyzed with regard to their photoconductive responses. We present conductance measurements under systematically varied illumination conditions along either the polar z-axis or perpendicular to it (x-cut). Apart from a pronounced photoconductance (PC) already under daylight and a large effect upon super-bandgap illumination in general, we observe (i) distinct spectral features when sweeping the excitation wavelength over the sub-bandgap region as then discussed in the context of deep and shallow trap states, (ii) extremely slow long-term relaxation for both light-on and light-off transients in the range of hours and days, (iii) a critical dependence of the photoresponse on the pre-illumination history of the sample, and (iv) a current–voltage hysteresis depending on both the illumination and the electrical-measurement conditions in a complex manner.
AU - Beyreuther, Elke
AU - Ratzenberger, Julius
AU - Roeper, Matthias
AU - Kirbus, Benjamin
AU - Rüsing, Michael
AU - Ivleva, Liudmila I.
AU - Eng, Lukas M.
ID - 47964
IS - 7
JF - Crystals
KW - Inorganic Chemistry
KW - Condensed Matter Physics
KW - General Materials Science
KW - General Chemical Engineering
SN - 2073-4352
TI - Photoconduction of Polar and Nonpolar Cuts of Undoped Sr0.61Ba0.39Nb2O6 Single Crystals
VL - 11
ER -
TY - JOUR
AB - Family-Literacy-Programme stellen eine gute Möglichkeit dar, Eltern in Bildungsprozesse
einzubeziehen. Am Beispiel des Programms „LIFE – Lesen in Familie erleben“ wird
die Wirkung auf elterliche Unterstützung beim Lesenlernen von Erstklässler*innen unter Einbezug von Eltern- und Kinderperspektive untersucht. Sowohl direkt nach dem
Programm als auch ein halbes Jahr später wirkte das Programm positiv auf verschiedene
Arten der Anschlusskommunikation beim gemeinsamen Lesen.
AU - Bonanati, Sabrina
AU - Gruchel, Nicole
AU - Kurock, Ricarda
AU - Buhl, Heike M.
ID - 32562
IS - 3
JF - Die Deutsche Schule
KW - Kooperation
KW - Familie
KW - Lesekompetenz
KW - Längsschnittstudie
KW - Intervention
SN - 0012-0731
TI - Teilhabe von Eltern an schulischem Lernen mit Family-Literacy-Programmen. Langzeiteffekte von „LIFE – Lesen in Familie erleben“ auf die elterliche Unterstützung beim Lesenlernen
VL - 113
ER -
TY - CONF
AB - Automatic transcription of meetings requires handling of overlapped speech, which calls for continuous speech separation (CSS) systems. The uPIT criterion was proposed for utterance-level separation with neural networks and introduces the constraint that the total number of speakers must not exceed the number of output channels. When processing meeting-like data in a segment-wise manner, i.e., by separating overlapping segments independently and stitching adjacent segments to continuous output streams, this constraint has to be fulfilled for any segment. In this contribution, we show that this constraint can be significantly relaxed. We propose a novel graph-based PIT criterion, which casts the assignment of utterances to output channels in a graph coloring problem. It only requires that the number of concurrently active speakers must not exceed the number of output channels. As a consequence, the system can process an arbitrary number of speakers and arbitrarily long segments and thus can handle more diverse scenarios.
Further, the stitching algorithm for obtaining a consistent output order in neighboring segments is of less importance and can even be eliminated completely, not the least reducing the computational effort. Experiments on meeting-style WSJ data show improvements in recognition performance over using the uPIT criterion.
AU - von Neumann, Thilo
AU - Kinoshita, Keisuke
AU - Boeddeker, Christoph
AU - Delcroix, Marc
AU - Haeb-Umbach, Reinhold
ID - 26770
KW - Continuous speech separation
KW - automatic speech recognition
KW - overlapped speech
KW - permutation invariant training
T2 - Interspeech 2021
TI - Graph-PIT: Generalized Permutation Invariant Training for Continuous Separation of Arbitrary Numbers of Speakers
ER -
TY - CONF
AU - von Neumann, Thilo
AU - Boeddeker, Christoph
AU - Kinoshita, Keisuke
AU - Delcroix, Marc
AU - Haeb-Umbach, Reinhold
ID - 29173
T2 - Speech Communication; 14th ITG Conference
TI - Speeding Up Permutation Invariant Training for Source Separation
ER -
TY - CONF
AB - In this paper we present our system for the Detection and Classification of Acoustic Scenes and Events (DCASE) 2021 Challenge Task 4: Sound Event Detection and Separation in Domestic Environments, where it scored the fourth rank. Our presented solution is an advancement of our system used in the previous edition of the task.We use a forward-backward convolutional recurrent neural network (FBCRNN) for tagging and pseudo labeling followed by tag-conditioned sound event detection (SED) models which are trained using strong pseudo labels provided by the FBCRNN. Our advancement over our earlier model is threefold. First, we introduce a strong label loss in the objective of the FBCRNN to take advantage of the strongly labeled synthetic data during training. Second, we perform multiple iterations of self-training for both the FBCRNN and tag-conditioned SED models. Third, while we used only tag-conditioned CNNs as our SED model in the previous edition we here explore sophisticated tag-conditioned SED model architectures, namely, bidirectional CRNNs and bidirectional convolutional transformer neural networks (CTNNs), and combine them. With metric and class specific tuning of median filter lengths for post-processing, our final SED model, consisting of 6 submodels (2 of each architecture), achieves on the public evaluation set poly-phonic sound event detection scores (PSDS) of 0.455 for scenario 1 and 0.684 for scenario as well as a collar-based F1-score of 0.596 outperforming the baselines and our model from the previous edition by far. Source code is publicly available at https://github.com/fgnt/pb_sed.
AU - Ebbers, Janek
AU - Haeb-Umbach, Reinhold
ID - 29308
SN - 978-84-09-36072-7
T2 - Proceedings of the 6th Detection and Classification of Acoustic Scenes and Events 2021 Workshop (DCASE2021)
TI - Self-Trained Audio Tagging and Sound Event Detection in Domestic Environments
ER -
TY - CONF
AB - Recently, there has been a rising interest in sound recognition via Acoustic Sensor Networks to support applications such as ambient assisted living or environmental habitat monitoring. With state-of-the-art sound recognition being dominated by deep-learning-based approaches, there is a high demand for labeled training data. Despite the availability of large-scale data sets such as Google's AudioSet, acquiring training data matching a certain application environment is still often a problem. In this paper we are concerned with human activity monitoring in a domestic environment using an ASN consisting of multiple nodes each providing multichannel signals. We propose a self-training based domain adaptation approach, which only requires unlabeled data from the target environment. Here, a sound recognition system trained on AudioSet, the teacher, generates pseudo labels for data from the target environment on which a student network is trained. The student can furthermore glean information about the spatial arrangement of sensors and sound sources to further improve classification performance. It is shown that the student significantly improves recognition performance over the pre-trained teacher without relying on labeled data from the environment the system is deployed in.
AU - Ebbers, Janek
AU - Keyser, Moritz Curt
AU - Haeb-Umbach, Reinhold
ID - 29306
T2 - Proceedings of the 29th European Signal Processing Conference (EUSIPCO)
TI - Adapting Sound Recognition to A New Environment Via Self-Training
ER -
TY - CHAP
AU - Schneider, Jennifer Nicole
ED - Beutner, Marc
ED - Pechuel, Rasmus
ED - Schneider, Jennifer
ID - 47957
T2 - Fostering Digitisation and Industry 4.0: Education – Vocation - Industry – Future. New Opportunities and Challenges for European VET. Insights in the DigI-VET Project
TI - Digital transformation in industry
ER -
TY - CHAP
AU - Schneider, Jennifer
ED - Beutner, Marc
ED - Pechuel, Rasmus
ED - Schneider, Jennifer
ID - 47966
T2 - Fostering Digitisation and Industry 4.0: Education – Vocation - Industry – Future. New Opportunities and Challenges for European VET. Insights in the DigI-VET Project
TI - Teaching and Learning Materials
ER -
TY - JOUR
AB - One objective of current research in explainable intelligent systems is to implement social aspects in order to increase the relevance of explanations. In this paper, we argue that a novel conceptual framework is needed to overcome shortcomings of existing AI systems with little attention to processes of interaction and learning. Drawing from research in interaction and development, we first outline the novel conceptual framework that pushes the design of AI systems toward true interactivity with an emphasis on the role of the partner and social relevance. We propose that AI systems will be able to provide a meaningful and relevant explanation only if the process of explaining is extended to active contribution of both partners that brings about dynamics that is modulated by different levels of analysis. Accordingly, our conceptual framework comprises monitoring and scaffolding as key concepts and claims that the process of explaining is not only modulated by the interaction between explainee and explainer but is embedded into a larger social context in which conventionalized and routinized behaviors are established. We discuss our conceptual framework in relation to the established objectives of transparency and autonomy that are raised for the design of explainable AI systems currently.
AU - Rohlfing, Katharina J.
AU - Cimiano, Philipp
AU - Scharlau, Ingrid
AU - Matzner, Tobias
AU - Buhl, Heike M.
AU - Buschmeier, Hendrik
AU - Esposito, Elena
AU - Grimminger, Angela
AU - Hammer, Barbara
AU - Haeb-Umbach, Reinhold
AU - Horwath, Ilona
AU - Hüllermeier, Eyke
AU - Kern, Friederike
AU - Kopp, Stefan
AU - Thommes, Kirsten
AU - Ngonga Ngomo, Axel-Cyrille
AU - Schulte, Carsten
AU - Wachsmuth, Henning
AU - Wagner, Petra
AU - Wrede, Britta
ID - 24456
IS - 3
JF - IEEE Transactions on Cognitive and Developmental Systems
KW - Explainability
KW - process ofexplaining andunderstanding
KW - explainable artificial systems
SN - 2379-8920
TI - Explanation as a Social Practice: Toward a Conceptual Framework for the Social Design of AI Systems
VL - 13
ER -
TY - GEN
AU - Fastlabend-Vargas, Daniel
ID - 49589
T2 - H-Soz-Kult
TI - Rezension zu: Dräger, Marco: Denkmäler im Geschichtsunterricht Frankfurt am Main 2021.
ER -
TY - JOUR
AB - The implementation of control systems in metal forming processes improves product quality and productivity. By controlling workpiece properties during the process, beneficial effects caused by forming can be exploited and integrated in the product design. The overall goal of this investigation is to produce tailored tubular parts with a defined locally graded microstructure by means of reverse flow forming. For this purpose, the proposed system aims to control both the desired geometry of the workpiece and additionally the formation of strain-induced α′-martensite content in the metastable austenitic stainless steel AISI 304 L. The paper introduces an overall control scheme, a geometry model for describing the process and changes in the dimensions of the workpiece, as well as a material model for the process-induced formation of martensite, providing equations based on empirical data. Moreover, measurement systems providing a closed feedback loop are presented, including a novel softsensor for in-situ measurements of the martensite content.
AU - Riepold, Markus
AU - Arian, Bahman
AU - Vasquez, Julian Rozo
AU - Homberg, Werner
AU - Walther, Frank
AU - Trächtler, Ansgar
ID - 23469
JF - Advances in Industrial and Manufacturing Engineering
SN - 2666-9129
TI - Model approaches for closed-loop property control for flow forming
ER -
TY - GEN
AU - Huybrechts, Yves
AU - Scholliers, Peter
ID - 49759
TI - "Searching for a Belgian culinary identity - Referat von Prof. Dr. Peter Scholliers" (VIDEO)
ER -
TY - GEN
AU - Huybrechts, Yves
ID - 49765
TI - "Der belgische Symbolismus - Interview mit dem Direktor der Alten Nationalgalerie, Dr. Ralph Gleis" (PODCAST)
ER -
TY - GEN
AU - Huybrechts, Yves
ID - 49752
TI - "Gebaute Träume - Wohnkultur in Flandern und Wallonien" (VIDEO)
ER -
TY - CHAP
AU - Neiske, Iris
ED - Buchner, J.
ED - Freisleben-Teutscher, C. F.
ED - Neiske, I.
ED - Morisse, I.
ID - 49867
SN - 9783755749165
T2 - Inverted Classroom and beyond 2021 10 Jahre #icmbeyond. Norderstedt
TI - Geflippte E-Tutor*innenschulungen
ER -
TY - JOUR
AB - The aim of the present study is to bring new momentum into research on students’
understanding of academic writing. Drawing on the idea that metaphors give insight into
implicit conceptions of abstract entities and processes, we developed a detailed and
differentiated set of conceptual metaphors that can be used to study student ideas about
writing in research, teaching, and interventions. A large sample of undergraduates produced
their everyday understanding of writing in short texts beginning with a self-generated
metaphor. Based on theories from cognitive linguistics, the conceptual metaphors in their
texts were analyzed in terms of their action quality (transitivity) and spatiality (spatial
primitives). The undergraduates’ conceptualizations were very heterogeneous. Most
metaphors depart strongly from scientific approaches to academic writing within cognitive
psychology and sociocultural theory. Roughly half of the metaphors could be collated to one
of four metaphor systems. Depending on the desired degree of abstraction or concreteness,
conceptual metaphors or metaphor systems can be employed in further studies to illuminate
thinking about writing.
AU - Scharlau, Ingrid
AU - Karsten, Andrea
AU - Rohlfing, Katharina
ID - 28696
IS - 3
JF - Journal of Writing Research
KW - metaphor analysis
KW - academic writing
KW - transitivity
KW - spatial primitives
SN - 2030-1006
TI - Building, emptying out, or dreaming? Action structures and space in undergraduates’ metaphors of academic writing
VL - 12
ER -
TY - JOUR
AU - Krollmann, Rabea
AU - Schmidt, Rebecca
AU - Spill, Annika
ID - 45252
JF - blog interdisziplinäre geschlechterforschung
TI - Grenzüberschreitung und Distanzierung – Geschlechterforschung in universitären Toiletten
ER -
TY - CONF
AU - Hohmann, Sascha
AU - Gschwind, Stéphane
AU - Müller, Andreas
AU - Nordine, Jeffrey
AU - Riesen, Timm-Emanuel
ED - Grötzebauch, Helmuth
ID - 50188
IS - 2021
SN - 2191-379X
T2 - PhyDid B
TI - Das Stellarium Gornergrat
ER -
TY - JOUR
AU - Ekström, Sylvia
AU - Frey, Jonas
AU - Gschwind, Stéphane
AU - Hohmann, Sascha
AU - Müller, Andreas
AU - Riesen, Timm-Emanuel
AU - Ruffieux, Simon
AU - Schlatter, Peter
ID - 50187
IS - 63
JF - SPG-Mitteilungen
TI - Stellarium Gornergrat – A swiss robotic Observatory for Education and Citizen Science
ER -
TY - BOOK
ED - Kißling, Magdalena
ID - 33698
TI - Kinder- und Jugendliteratur intermedial. Unterrichtsanregungen und -materialien zum literarischen Lernen im Medienverbund anhand von Emil und die Detektive (Gym/Ge) und Jakob der Lügner (BK); erstellt von Masterstudierenden der Universität Paderborn
ER -
TY - CONF
AB - Arburg Plastic Freeforming (APF) is an additive manufacturing process with which three-dimensional, thermoplastic components can be produced layer by layer. Visual and geometrical properties are a major criterion for characterizing the resulting component quality. The aim of this study was to investigate the influences on visual and geometrical properties of APF components depending on process parameters. Initially the focus was on the analysis of the shrinkage behavior of ABS-M30 (Stratasys). On the basis of the results and an existing procedure by the machine manufacturer, an optimized procedure for determining the scaling factors was developed to counteract the shrinkage. With this procedure a higher dimensional accuracy of the components can be achieved. In addition, it was investigated whether an adaption of the form factor based on a mathematical model depending on the component geometry makes sense. The results were transferred into manufacturing guidelines, which allow the user of the APF-technology to optimize process parameters more efficiently.
AU - Moritzer, Elmar
AU - Hecker, Felix
AU - Elsner, Christian Lennart
AU - Hirsch, André
ED - Bourell, David
ID - 24101
T2 - Proceedings: 2021 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2021)
TI - Investigations for the Optimization of Visual and Geometrical Properties of Arburg Plastic Freeforming Components
ER -
TY - CONF
AB - The additive manufacturing process Fused Deposition Modeling (FDM) is established in the industry for many years. A new, similar process to FDM is the Arburg Plastic Freeforming (APF). The main differences between both processes are the form of the starting material (FDM: Filaments, APF: Conventional granulate) and the material deposition during the layer formation (FDM: Melt strand, APF: fine molten droplets).
Since the two processes can be used in similar applications, the aim of this study is to compare both processes in a holistic way. Furthermore, the advantages and disadvantages of the processes are to be highlighted. The systematic comparison between a Stratasys 400mc and the Freeformer 200-3X is divided into the areas of component properties, design limitations and economic efficiency. The material ABS-M30 (Stratasys) is used in both processes. The results show comparable component properties regarding mechanical and optical properties but also differences in design limitations and cost efficiency.
AU - Moritzer, Elmar
AU - Hecker, Felix
AU - Driediger, Christine
AU - Hirsch, André
ED - Bourell, David
ID - 24099
T2 - Proceedings: 2021 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2021)
TI - Comparison of Component Properties and Economic Efficiency of the Arburg Plastic Freeforming and Fused Deposition Modeling
ER -
TY - CONF
AB - The Arburg Plastic Freeforming (APF) is an additive manufacturing process with which three-dimensional, thermoplastic components can be produced layer by layer. One disadvantage of the APF is the long residence time of the molten material in the plasticizing unit compared to conventional injection moulding. The dosing volume is emptied very slowly due to only discharging fine plastic droplets. As a result, long residence times can be expected, which can lead to thermal degradation of the material.
The aim of this study was to develop a model for calculating the residence time of the material in the APF. The residence time of the material in the thermally critical dosing volume is predicted using software developed in-house. The accuracy of the model could be verified by experimental investigations. Finally, the thermal degradation of the material was investigated by analyzing the correlation to the mechanical properties of tensile strength specimens.
AU - Moritzer, Elmar
AU - Hecker, Felix
AU - Hirsch, André
ED - Bourell, David
ID - 24096
T2 - Proceedings: 2021 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2021)
TI - Investigation and Modeling of the Residence Time Dependent Material Degradation in the Arburg Plastic Freeforming
ER -
TY - JOUR
AU - Kückmann, Marie-Ann
AU - Kundisch, Heike
ID - 50363
JF - Didaktisierung des Digitalen: Zur Entwicklung berufs- und wirtschaftspädagogischer Studiengänge
TI - Denken mit dem Stift?! – Digitale Visualisierungsprozesse als Zugang zu komplexen wirtschafts- und berufspädagogischen Themenfeldern.
ER -
TY - CONF
AU - Leffrang, Dirk
AU - Müller, Oliver
ID - 26812
T2 - IEEE Workshop on TRust and EXpertise in Visual Analytics
TI - Should I Follow this Model? The Effect of Uncertainty Visualization on the Acceptance of Time Series Forecasts
ER -
TY - CONF
AB - In automotive and other fields of application media-carrying components often have complex, flow-optimized geometries and are made of plastics for reasons of weight and cost. Therefore, the laser sintering technology is predestinated to manufacture these components as it offers a very high degree of design freedom and good mechanical properties.
For industrial applications the long-term properties of the SLS material in contact with liquid media are important and were therefore investigated for PA12, PP and PA613. Hereby, different media such as motor oil or Glysantin based coolant were tested with different temperatures and immersion times of up to 26 weeks. The mechanical properties were tested after immersion and compared to injection molded samples. Furthermore, laser sintering design guidelines for media-carrying components were developed. These guidelines for instance include the minimum wall thickness to ensure media tightness and the removal of powder from channels with a high length to diameter ratio.
AU - Kletetzka, Ivo
AU - Kummert, Christina
AU - Schmid, Hans-Joachim
ID - 24160
T2 - Proceedings of the 32nd Annual International Solid Freeform Fabrication Symposium
TI - Laser Sintering Design Guidelines for media transmitting Components
VL - 32
ER -
TY - CHAP
AB - In diesem Beitrag wird das Konzept des student engagement mit den drei Dimensionen Verhalten, Emotion und Kognition skizziert und in Bezug auf die unterstützenden Faktoren für Lehre auf Distanz in digitalen Lehr-Lernsettings untersucht. Ein Abgleich der theoretischen Grundlagen mit Forschungsergebnissen verschiedener Studien zum Onlinesemester 2020 sowie eine Konkretisierung durch Evaluationen aus Seminaren der englischen Sprachwissenschaft und der Kunstdidaktik gibt Aufschluss darüber, wie ein geeignetes how to engage auch in digitalen Lehr-Lernsettings gelingen kann. Darüber hinaus lassen die Ausführungen erkennen, dass die unterstützenden Faktoren häufig in ähnlich priorisiert werden. Daraus ergibt sich eine Reihenfolge mit dem unterstützenden Umfeld an erster, aktivem und kollaborativem Lernen an zweiter, Erleben von Kompetenz an dritter und akademischer Herausforderung an vierter Stelle. Die Ergebnisse können damit einen Weg aufzeigen, wie auch in ungewohnten Lehr-Lernsettings sukzessive ein geeignetes how to engage entwickelt werden kann, um student engagement zu fördern.
AU - Schmidt, Rebekka
AU - Mindt, Ilka
ED - Neiske, Iris
ED - Osthushenrich, Judith
ED - Schaper, Niclas
ED - Trier, Ulrike
ED - Vöing, Nerea
ID - 32488
SN - 2749-7623
T2 - Hochschule auf Abstand. Ein multiperspektivischer Zugang zur digitalen Lehre
TI - Student engagement in digitalen Lehr-Lern-Szenarien
ER -
TY - JOUR
AU - Spener, Anna Maria
ID - 48691
JF - Undercurrents – Forum für linke Literaturwissenschaft
TI - "Unsere Rache ist unsere Existenz. Unsere Waffe ist die Sprache." Zum desintegrativen Potenzial von Mirna Funks Roman "Winternähe"
VL - 16
ER -
TY - JOUR
AU - Blank, Andreas
ID - 50862
IS - 5
JF - Journal of Modern Philosophy
TI - “Mably on Esteem, Republicanism, and the Question of Human Corruption.”
VL - 3
ER -
TY - JOUR
AU - Blank, Andreas
ID - 50863
IS - 6
JF - History of European Ideas
TI - “The Morality of the Desire for Esteem: Gassendi and the Augustinian Challenge.”
VL - 47
ER -
TY - JOUR
AU - Blank, Andreas
ID - 50864
IS - 4
JF - European Journal of Philosophy
TI - “Wolff on Duties of Esteem in the Law of Peoples.”
VL - 29
ER -
TY - CHAP
AU - Haker, Christoph
AU - Otterspeer, Lukas
ED - Sehmer, Julian
ED - Simon, Stephanie
ED - Ten Elsen, Jennifer
ED - Thiele, Felix
ID - 51310
SN - 9783658325596
T2 - recht extrem? Dynamiken in zivilgesellschaftlichen Räumen
TI - Die epistemische Dimension der Neuen Rechten. Von einer Kritik des Wissenschafts- und Bildungsverständnisses der Neuen Rechten zu einer Selbstkritik
ER -
TY - JOUR
AB - Critique has run out of steam – this diagnosis by Bruno Latour is crucial for the “Manifesto for post-critical education” as well as for the on_education issue “The Fatique of Critique?”. With this essay, we contradict Latour's diagnosis. Latour’s polemic against critique is based firstly on a questionable diagnosis of our time and secondly on a general and programmatic critique of sociology. Against that, we bring out two main points. The first insight highlights that change is initially dependent on variations that can only arise from a negation of the existing. The second insight comes from the sociology of critique, which paradoxically sees success in the failure of critique.
AU - Haker, Christoph
AU - Otterspeer, Lukas
ID - 51315
IS - 9
JF - On Education. Journal for Research and Debate
SN - 2571-7855
TI - Against Latour – On the Questionable Foundations of Post-Critical Pedagogy
VL - 3
ER -
TY - JOUR
AU - Haker, Christoph
AU - Otterspeer, Lukas
ID - 51311
JF - BEHEMOTH. A Journal on Civilisation
TI - Die Beweglichkeit der Kritik: zur Wechselbeziehung von Kontextualisierung und Objektivierung im digitalen Zeitalter
ER -
TY - JOUR
AB - To analyze the influence of suspension kinematics on tire wear, detailed simulation models are required. In this study, a non-linear, flexible multibody model of a rear axle system is built up in the simulation software MSC Adams/View. The physical model comprises the suspension kinematics, compliance, and dynamics as well as the non-linear behavior of the tire using the FTire model. FTire is chosen because it has a separate tire tread model to compute the contact pressure and friction force distribution in the tire contact patch. To build up the simulation model, a large amount of data is needed. Bushings, spring, and damper characteristics are modeled based on measurements. For the structural components (e.g., control arms), reverse engineering techniques are used. The components are 3D-scanned, reworked, and included as a modal reduced finite element (FE)-model using component mode synthesis by Craig–Bampton. Finally, the suspension model is validated by comparing the simulated kinematic and compliance characteristics to experimental results. To investigate the interaction of suspension kinematics and tire wear, straight line driving events, such as acceleration, driving with constant velocity, and deceleration, are simulated with different setups of wheel suspension kinematics. The influence of the setups on the resulting friction work between tire and road is examined, and an exemplarily calculation of tire wear based on a validated FTire tire model is carried out. The results demonstrate, on the one hand, that the chosen concept of elasto-kinematic axle leads to a relatively good match with experimental results and, on the other hand, that there are significant possibilities to reduce tire wear by adjusting the suspension kinematics.
AU - Schütte, Jan
AU - Sextro, Walter
ID - 27508
JF - Vehicles
SN - 2624-8921
TI - Tire Wear Reduction Based on an Extended Multibody Rear Axle Model
ER -
TY - JOUR
AU - Martin, Sven
AU - Schütte, Jan
AU - Bäumler, C.
AU - Sextro, Walter
AU - Tröster, Thomas
ID - 29293
JF - Forces in Mechanics
SN - 2666-3597
TI - Identification of joints for a load-adapted shape in a body in white using steady state vehicle simulations
VL - 6
ER -
TY - CHAP
AU - Schneider, Jennifer Nicole
ED - Beutner, Marc
ED - Pechuel, Rasmus
ED - Schneider, Jennifer
ID - 47962
T2 - Fostering Digitisation and Industry 4.0: Education – Vocation - Industry – Future. New Opportunities and Challenges for European VET. Insights in the DigI-VET Project
TI - Digitalisation in the Classroom – Learning Tools
ER -
TY - BOOK
ED - Beutner, Marc
ED - Pechuel, Rasmus
ED - Schneider, Jennifer Nicole
ID - 47978
TI - Fostering Digitisation and Industry 4.0: Education – Vocation – Industry – Future. New Opportunities and Challenges for European VET. Insight in the DigI-VET Project
ER -
TY - GEN
AU - Hilgert, Joachim
AU - Weich, Tobias
AU - Wolf, L.
ID - 51503
TI - Higher-rank quantum-classical correspondence
ER -