TY - CHAP
AU - Eickelmann, Birgit
ID - 44678
T2 - Remote Schools. Schulisches Distanzlernen in und nach der Corona-Pandemie.
TI - Digitale Schultransformation ganzheitlich gestalten
ER -
TY - GEN
AU - Eickelmann, Birgit
ID - 44680
TI - Lehren aus der Pandemie: Gleiche Chancen für alle Kinder und Jugendlichen sichern. Stellungnahme der Expert*innenkommission der Friedrich-Ebert-Stiftung
ER -
TY - CONF
AB - Challenges in decisions on technical changes are the lack of knowledge about the expected impact and change propagation. Currently, no literature study contains a systematic differentiation and evaluation of existing approaches, which is a prerequisite for practitioners to select a suitable approach. This research aims at defining differentiation criteria as well as generally applicable requirements for evaluation. A four-step approach is used: systematic literature review on approaches for impact analysis of engineering changes (1), categorization and prioritization of approaches based on reoccuring elements (2), derivation of context specific requirements for evaluation (3), and evaluation of approaches (4). The result indicates existing potential of object-oriented modeling approaches.
AU - Gräßler, Iris
AU - Wiechel, Dominik
ED - Krause, Dieter
ED - Paetzold, Kristin
ED - Wartzack, Sandro
ID - 24280
KW - Engineering Change Management
KW - Impact Analysis
KW - Engineering Changes
KW - Model-based Systems Engineering
KW - Product Developmen
T2 - DS 111: Proceedings of the 32nd Symposium Design for X
TI - Systematische Bewertung von Auswirkungsanalysen des Engineering Change Managements
ER -
TY - CONF
AU - Gräßler, Iris
AU - Roesmann, Daniel
AU - Wiechel, Dominik
AU - Preuß, Daniel
AU - Pottebaum, Jens
ID - 26866
T2 - 54th CIRP Conference on Manufacturing Systems
TI - Determine similarity of assembly operations using semantic technology
ER -
TY - CONF
AU - Gräßler, Iris
AU - Wiechel, Dominik
AU - Pottebaum, Jens
ID - 23392
T2 - Proceedings of 19th Drive Train Technology Conference (ATK 2021), 9. - 11. Mrz. 2021
TI - Role model of model-based systems engineering application
ER -
TY - CHAP
AU - Schreckenberg, Stefan
ED - Mecke, Jochen
ED - Schoentjes, Pierre
ED - Donnarieix, Anne-Sophie
ID - 44693
T2 - Esthétique de la guerre - Éthique de la paix. Un siècle de littérature sur la Grande Guerre
TI - Éthiques et esthétiques de la Grande Guerre chez des auteurs de la génération des petits-enfants
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 - In order to optimize production processes and to avoid errors, it is not only necessary to automate processes, but also to integrate workers with their individual personality and skill profiles. For this purpose, human factors should be considered in the entire design process. The integrated view of mental human models, the cognitive demand of the working environment and the automation design is essential. Human-System Integration (HSI) constitutes a promising approach. Current model-based approaches offer possibilities to analyze and optimize tasks within an overall system, but they still lack integration. This leads to the research question: How can human factors be integrated into a system model of a socio-technical, Cyber-Physical Production System? The paper at hand contributes an approach of human factor integration into the procedure of Model-Based Systems Engineering for Cyber-Physical Production Systems (CPPS). The approach combines a system model of a CPPS with HSI concepts. In accordance to the benefits of MBSE, SysML is selected to integrate human factors in the development process of a CPPS. The approach is divided into five steps, which includes the extension of the SysML meta model. This allows the optimization of skill-based human-machine interaction. Defined HSI-Profiles enable system developers to integrate employee requirements at early stages within the development process. The approach is demonstrated by the maintenance of a 3D-Printer as a case example. This research enables system developers to depict individual workers with the help of the developed concepts and systematically integrate them into the development process of a CPPS.
AU - Gräßler, Iris
AU - Wiechel, Dominik
AU - Roesmann, Daniel
ID - 24281
SN - 2212-8271
T2 - Procedia CIRP
TI - Integrating human factors in the model based development of cyber-physical production systems
ER -
TY - CONF
AU - Hesse, Philipp
AU - Gräßler, Iris
ED - Biedermann, Hubert
ED - Posch, Wolfgang
ED - Vorbach, Stefan
ID - 24444
T2 - Digitalisierung im Kontext von Nachhaltigkeit und Klimawandel
TI - Digitaler Zwilling zur Gestaltung der Prozesse im End-of-Life
VL - 9
ER -
TY - GEN
AU - Gräßler, Iris
AU - Hentze, Julian
AU - Hesse, Philipp
AU - Preuß, Daniel
AU - Thiele, Henrik
AU - Wiechel, Dominik
AU - Bothen, Martin
AU - Bruckmann, Tobias
AU - Dattner, Michael
AU - Ehl, Thomas
AU - Hawlas, Martin
AU - Krimpmann, Christoph
AU - Lachmayer, Roland
AU - Knöchelmann, Marvin
AU - Mock, Randolf
AU - Mozgova, Iryna
AU - Schneider, Maximilian
AU - Stollt, Guido
ID - 27680
TI - VDI/VDE 2206 - Entwicklung mechatronischer und cyber-physischer Systeme
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 - GEN
AU - Dewerth, Mats-Ole
AU - Neukötter, Moritz
ID - 42989
TI - Entwicklung eines Versuchsaufbaus zur rheo-optischen Untersuchung des Dehnverhaltens von Polymerschmelzen und -lösungen am Hochdruck-Kapillarrheometer (Studienarbeit)
ER -
TY - GEN
AU - Hütte, Marvin
AU - Neukötter, Moritz
ID - 43004
TI - Weiterentwicklung des Versuchsaufbaus zur Untersuchung von Polymerschmelzen und -lösungen am Hochdruck-Kapillarrheometer
ER -
TY - JOUR
AU - Mattiolo, Davide
AU - Steffen, Eckhard
ID - 23456
IS - 1
JF - Journal of Graph Theory
KW - factorization
KW - perfect matchings
KW - regular graphs
KW - r-graphs
SN - 0364-9024
TI - Highly edge‐connected regular graphs without large factorizable subgraphs
VL - 99
ER -
TY - JOUR
AU - Klopp, Antje
AU - Steffen, Eckhard
ID - 21827
JF - Graphs and Combinatorics
SN - 0911-0119
TI - Fractional Matchings, Component-Factors and Edge-Chromatic Critical Graphs
ER -
TY - JOUR
AU - Steffen, Eckhard
AU - Vogel, Alexander
ID - 13445
JF - European J. Combinatorics
TI - Concepts of signed graph coloring
VL - 91
ER -
TY - CHAP
AU - Dopheide, F.
AU - Freitag, Christine
AU - Koch, L.
AU - Struchholz, C.
ED - Gerholz, Karl-Heinz
ID - 37537
T2 - Impulse zu Methoden in der deutschsprachigen Civic Engagement-Forschung
TI - Gesellschaftliche Wirkprozesse des Civic Engagement qualitativ erforschen
ER -
TY - JOUR
AU - Freitag, Christine
ID - 37539
IS - 4
JF - Katechetische Blätter
TI - Denk-Wege zu einer religionssensiblen Schulkultur: erziehungswissenschaftliche Perspektiven
ER -
TY - CHAP
AU - Freitag, Christine
ED - Gerholz, Karl-Heinz
ID - 37533
T2 - Impulse zu Methoden in der deutschsprachigen Civic Engagement-Forschung
TI - Gesellschaftlich Wirkprozesse des Civic Engagement qualitativ erforschen
ER -
TY - GEN
AB - Erklärvideos gewinnen auch im Kontext des Physikunterrichts verstärkt an Relevanz. Um zu evaluieren, welche Gestaltungsaspekte ein wirkungsvolles Erklärvideo ausmachen, ist es das Ziel der vorliegenden Masterarbeit herauszufinden, welchen Einfluss die kohärente Gestaltung eines Erklärvideos hat. Dazu wird die Forschungsfrage gestellt: „Welchen Einfluss hat die kohärente Gestaltung eines Erklärvideos auf den dadurch hervorgerufenen Lernzuwachs im Vergleich zu einem in der Hinsicht nicht optimierten Video?“ Um die Forschungsfrage zu beantworten, ist eine quantitative Studie im Prä- und Posttestdesign mit Schüler:innen der Jahrgangsstufe Q1 durchgeführt worden. Außerdem wurde in verschiedenen Kategorien nach einer Bewertung der Videos gefragt.
Die Auswertung zeigt, dass durch das optimierte Video mit einem kleinen Effekt bessere Ergebnisse erzielt wurden, diese aber nicht signifikant und auch nicht für alle Aufgaben besser sind. Die Schüler:innen bewerteten das nicht optimierte Video in allen Kategorien besser als das optimierte Video. Auch dieses Ergebnis ist nicht signifikant.
AU - Hörnlein, Madeleine
ID - 35839
TI - Untersuchung von Erklärvideos im Physikunterricht - Wirksamkeit von Kohärenz
ER -
TY - JOUR
AB - This study uniquely employs a fuzzy-set qualitative comparative analysis (fsQCA) technique to account for complex relationships in consumption. The fsQCA technique assumes that relationships are based on a set–subset relationship. This assumption is fundamental when decision-makers are affected by information asymmetry and are, thus, required to jointly evaluate the credibility and reliability of a range of external signals. This issue also affects consumers in markets for cultural goods, where the quality of products is not known with certainty in advance of the purchase decision. Our study uses fsQCA to establish the effect of different quality signals on consumption in the US market for video game software. Our results show that reviews from professional critics alongside brand extension and multi-platform release strategies act as signals of product quality and, therefore, lead to high sales performance.
AU - Kaimann, Daniel
AU - Cox, Joe
ID - 44896
IS - 23
JF - Sustainability
KW - Management
KW - Monitoring
KW - Policy and Law
KW - Renewable Energy
KW - Sustainability and the Environment
KW - Geography
KW - Planning and Development
SN - 2071-1050
TI - A Comparative Analysis of Consumption: Evidence from a Cultural Goods Market
VL - 13
ER -
TY - JOUR
AU - Kaimann, Daniel
AU - Tanneberg, Ilka
AU - Cox, Joe
ID - 21289
IS - 1
JF - Managerial and Decision Economics
SN - 0143-6570
TI - “I will survive”: Online streaming and the chart survival of music tracks
VL - 42
ER -
TY - JOUR
AB - AbstractChanges in winery ratings in leading wine guides, that is, improvements as well as deteriorations, are typically attributed to corresponding changes in the quality of the wines produced by the respective winery. What remains unexplored in this context is changes in editorship and/or changes in the composition of the wine tasting teams working for the respective guide. Using data from two particularly prestigious German wine guides (Gault Millau and Vinum), this paper shows that these latter changes have a rather small, yet statistically significant impact on changes in winery ratings. Thus, consumers are well-advised to consider these changes before making their purchasing decision. (JEL Classifications: L21, M30, Q13)
AU - Frick, Bernd
ID - 44899
IS - 4
JF - Journal of Wine Economics
KW - Horticulture
KW - General Business
KW - Management and Accounting
KW - Food Science
SN - 1931-4361
TI - The Legacy of Gurus: The Impact of Armin Diel and Joel Payne on Winery Ratings in Germany
VL - 15
ER -
TY - JOUR
AU - Roos, E.
AU - Brehm, Martin
ID - 45001
JF - Phys. Chem. Chem. Phys.
TI - A Force Field for Bio-Polymers in Ionic Liquids (BILFF) – Part 1: [EMIm][OAc] / Water Mixtures
VL - 23
ER -
TY - JOUR
AU - Brehm, Martin
AU - Thomas, M.
ID - 45004
JF - Molecules
TI - Optimized Atomic Partial Charges and Radii Defined by Radical Voronoi Tessellation of Bulk Phase Simulations
VL - 26 (7)
ER -
TY - JOUR
AU - Roy, S.
AU - Brehm, Martin
AU - Sharma, S.
AU - Wu, F.
AU - Maltsev, D.
AU - Halstenberg, P.
AU - Gallington, L.
AU - Mahurin, S.
AU - Dai, S.
AU - Ivanov, A.
AU - Margulis, C.
AU - Bryantsev, V.
ID - 45005
JF - J. Phys. Chem. B
TI - Unraveling Local Structure of Molten Salts via X-Ray Scattering, Raman Spectroscopy, and ab initio Molecular Dynamics
VL - 125 (22)
ER -
TY - JOUR
AU - Triolo, A.
AU - Pietro, M. E. Di
AU - Mele, A.
AU - Celso, F. Lo
AU - Brehm, Martin
AU - Lisio, V. Di
AU - Martinelli, A.
AU - Chater, P.
AU - Russina, O.
ID - 45006
JF - J. Chem. Phys.
TI - Liquid Structure and Dynamics in the Choline Acetate:Urea 1:2 Deep Eutectic Solvent
VL - 154
ER -
TY - JOUR
AU - Codescu, M.-A.
AU - Weiß, M.
AU - Brehm, Martin
AU - Kornilov, O.
AU - Sebastiani, D.
AU - Nibbering, E. T. J.
ID - 45003
JF - J. Phys. Chem. A
TI - Switching Between Proton Vacancy and Excess Proton Transfer Pathways in the Reaction Between 7-Hydroxyquinoline and Formate
VL - 125 (9)
ER -
TY - JOUR
AU - Mukherjee, M.
AU - Tripathi, D.
AU - Brehm, Martin
AU - Riplinger, C.
AU - Dutta, A. K.
ID - 45000
JF - J. Chem. Theory Comput.
TI - Efficient EOM-CC-Based Protocol for the Calculation of Electron Affinity of Solvated Nucleobases: Uracil as a Case Study
VL - 17 (1)
ER -
TY - JOUR
AU - Triolo, A.
AU - Celso, F. Lo
AU - Brehm, Martin
AU - Lisio, V. Di
AU - Russina, O.
ID - 45002
JF - J. Mol. Liq.
TI - Liquid Structure of a Choline Chloride-Water Natural Deep Eutectic Solvent: A Molecular Dynamics Characterization
VL - 331
ER -
TY - CONF
AU - Knickenberg, Margarita
AU - Zurbriggen, C.
ID - 44153
TI - Qualität sozialer Interaktionen von Jugendlichen mit emotionalen Problemen oder Problemen im Umgang mit Peers im Unterricht – Eine Pilotstudie mit der Experience Sampling Method
ER -
TY - CONF
AU - DeVries, J. M.
AU - Knickenberg, Margarita
AU - Trygger, M.
ID - 44152
TI - Gender, special education needs, and inclusion: Evidence from the Perceptopions of Inclusion Questionnaire in Sweden
ER -
TY - JOUR
AU - DeVries, Jeffrey M.
AU - Knickenberg, Margarita
AU - Trygger, Maria
ID - 44151
IS - 3
JF - European Journal of Special Needs Education
KW - Developmental and Educational Psychology
KW - Health Professions (miscellaneous)
KW - Education
SN - 0885-6257
TI - Academic self-concept, perceptions of inclusion, special needs and gender: Evidence from inclusive classes in Sweden
VL - 37
ER -
TY - JOUR
AB -
Context
Return to running (RTR) after anterior cruciate ligament reconstruction (ACLR) is a crucial milestone. However, how and when to start a running program are uncertain.
Objective
To explore the feasibility of a structured program to reintroduce running after ACLR and evaluate the predictive value of potential predictors of short-term success.
Design
Longitudinal cohort study.
Setting
Local research center and participants' homes.
Patients or Other Participants
Thirty-five participants were recruited after ACLR.
Intervention(s)
Program with a progression algorithm to reintroduce running (10 running sessions in 14 days).
Main Outcome Measure(s)
The criterion for short-term success was no exacerbation of symptoms. Potential predictors were (1) the International Knee Documentation Committee (IKDC) subjective knee form score, (2) ACL Return to Sport after Injury questionnaire score, (3) quadriceps and hamstrings strength, (4) step-down endurance test, and (5) modified Star Excursion Balance test. Descriptive statistics were performed to study the feasibility of the RTR program, and Poisson regression analysis was used to evaluate predictors of success.
Results
Of the 34 participants, 33 completed the RTR program. Sixteen participants experienced some temporary exacerbation of symptoms, but only 1 had to stop the program. The initial IKDC score was the only significant predictor of a successful RTR, with an area under the receiver operating characteristic curve of 80.4%. An IKDC cut-off of 63.7/100 differentiated responders and nonresponders with the highest sensitivity and specificity (77.8% and 75.0%, respectively). A participant with an IKDC score above this threshold had a 3-fold greater chance of success.
Conclusions
Our results confirm the feasibility of our RTR program and progression algorithm after ACLR. Clinicians should use an IKDC score of >64 as a criterion to reintroduce running after ACLR to increase the likelihood of short-term success.
AU - Pairot de Fontenay, Benoit
AU - Van Cant, Joachim
AU - Gokeler, Alli
AU - Roy, Jean-Sébastien
ID - 45115
IS - 6
JF - Journal of Athletic Training
KW - Physical Therapy
KW - Sports Therapy and Rehabilitation
KW - Orthopedics and Sports Medicine
KW - General Medicine
SN - 1938-162X
TI - Reintroduction of Running After Anterior Cruciate Ligament Reconstruction With a Hamstrings Graft: Can We Predict Short-Term Success?
VL - 57
ER -
TY - JOUR
AB - Context: Only 55% of the athletes return to competitive sports after an anterior cruciate ligament (ACL) injury. Athletes younger than 25 years who return to sports have a second injury rate of 23%. There may be a mismatch between rehabilitation contents and the demands an athlete faces after returning to sports. Current return-to-sports (RTS) tests utilize closed and predictable motor skills; however, demands on the field are different. Neurocognitive functions are essential to manage dynamic sport situations and may fluctuate after peripheral injuries. Most RTS and rehabilitation paradigms appear to lack this aspect, which might be linked to increased risk of second injury. Objective: This systematic and scoping review aims to map existing evidence about neurocognitive and neurophysiological functions in athletes, which could be linked to ACL injury in an integrated fashion and bring an extensive perspective to assessment and rehabilitation approaches. Data Sources: PubMed and Cochrane databases were searched to identify relevant studies published between 2005 and 2020 using the keywords ACL, brain, cortical, neuroplasticity, cognitive, cognition, neurocognition, and athletes. Study Selection: Studies investigating either neurocognitive or neurophysiological functions in athletes and linking these to ACL injury regardless of their design and technique were included. Study Design: Systematic review. Level of Evidence: Level 3. Data Extraction: The demographic, temporal, neurological, and behavioral data revealing possible injury-related aspects were extracted and summarized. Results: A total of 16 studies were included in this review. Deficits in different neurocognitive domains and changes in neurophysiological functions could be a predisposing risk factor for, or a consequence caused by, ACL injuries. Conclusion: Clinicians should view ACL injuries not only as a musculoskeletal but also as a neural lesion with neurocognitive and neurophysiological aspects. Rehabilitation and RTS paradigms should consider these changes for assessment and interventions after injury.
AU - Piskin, Daghan
AU - Benjaminse, Anne
AU - Dimitrakis, Panagiotis
AU - Gokeler, Alli
ID - 45135
IS - 4
JF - Sports Health: A Multidisciplinary Approach
KW - Physical Therapy
KW - Sports Therapy and Rehabilitation
KW - Orthopedics and Sports Medicine
SN - 1941-7381
TI - Neurocognitive and Neurophysiological Functions Related to ACL Injury: A Framework for Neurocognitive Approaches in Rehabilitation and Return-to-Sports Tests
VL - 14
ER -
TY - JOUR
AB - Background: Differential learning (DL) is a motor learning method characterized by high amounts of variability during practice and is claimed to provide the learner with a higher learning rate than other methods. However, some controversy surrounds DL theory, and to date, no overview exists that compares the effects of DL to other motor learning methods.Objective: To evaluate the effectiveness of DL in comparison to other motor learning methods in the acquisition and retention phase.Design: Systematic review and exploratory meta-analysis.Methods: PubMed (MEDLINE), Web of Science, and Google Scholar were searched until February 3, 2020. To be included, (1) studies had to be experiments where the DL group was compared to a control group engaged in a different motor learning method (lack of practice was not eligible), (2) studies had to describe the effects on one or more measures of performance in a skill or movement task, and (3) the study report had to be published as a full paper in a journal or as a book chapter.Results: Twenty-seven studies encompassing 31 experiments were included. Overall heterogeneity for the acquisition phase (post-pre; I2 = 77%) as well as for the retention phase (retention-pre; I2 = 79%) was large, and risk of bias was high. The meta-analysis showed an overall small effect size of 0.26 [0.10, 0.42] in the acquisition phase for participants in the DL group compared to other motor learning methods. In the retention phase, an overall medium effect size of 0.61 [0.30, 0.91] was observed for participants in the DL group compared to other motor learning methods.Discussion/Conclusion: Given the large amount of heterogeneity, limited number of studies, low sample sizes, low statistical power, possible publication bias, and high risk of bias in general, inferences about the effectiveness of DL would be premature. Even though DL shows potential to result in greater average improvements between pre- and post/retention test compared to non-variability-based motor learning methods, more high-quality research is needed before issuing such a statement. For robust comparisons on the relative effectiveness of DL to different variability-based motor learning methods, scarce and inconclusive evidence was found.
AU - Tassignon, Bruno
AU - Verschueren, Jo
AU - Baeyens, Jean-Pierre
AU - Benjaminse, Anne
AU - Gokeler, Alli
AU - Serrien, Ben
AU - Clijsen, Ron
ID - 45140
JF - Frontiers in Psychology
KW - General Psychology
SN - 1664-1078
TI - An Exploratory Meta-Analytic Review on the Empirical Evidence of Differential Learning as an Enhanced Motor Learning Method
VL - 12
ER -
TY - JOUR
AB - Individuals after anterior cruciate ligament reconstruction (ACLR) have a high rate of reinjury upon return to competitive sports. Deficits in motor control may influence reinjury risk and can be addressed during rehabilitation with motor learning strategies. When instructing patients in performing motor tasks after ACLR, an external focus of attention directed to the intended movement effect has been shown to be more effective in reducing reinjury risk than an internal focus of attention on body movements. While this concept is mostly agreed upon, recent literature has made it clear that the interpretation and implementation of an external focus of attention within ACLR rehabilitation needs to be better described. The purpose of this commentary is to provide a clinical framework for the application of attentional focus strategies and guide clinicians towards effectively utilizing an external focus of attention in rehabilitation after ACLR. Level of Evidence 5
AU - Singh, Harjiv
AU - Gokeler, Alli
AU - Benjaminse, Anne
ID - 45138
IS - 6
JF - International Journal of Sports Physical Therapy
KW - Rehabilitation
KW - Orthopedics and Sports Medicine
KW - Physical Therapy
KW - Sports Therapy and Rehabilitation
SN - 2159-2896
TI - Effective Attentional Focus Strategies after Anterior Cruciate Ligament Reconstruction: A Commentary
VL - 16
ER -
TY - JOUR
AU - Dingenen, Bart
AU - Billiet, Bart
AU - De Baets, Liesbet
AU - Bellemans, Johan
AU - Truijen, Jan
AU - Gokeler, Alli
ID - 45151
JF - Physical Therapy in Sport
KW - Physical Therapy
KW - Sports Therapy and Rehabilitation
KW - Orthopedics and Sports Medicine
KW - General Medicine
SN - 1466-853X
TI - Rehabilitation strategies of Flemish physical therapists before and after anterior cruciate ligament reconstruction: An online survey
VL - 49
ER -
TY - GEN
AU - N., N.
ID - 42317
TI - Die Aufteilung der Barentsseegebiete mithilfe des Adjusted Winner Verfahrens bei asymmetrischen Machtverhältnissen
ER -
TY - GEN
AU - N., N.
ID - 42315
TI - Versionisierung von Serviceleistungen auf Videoplattformen
ER -
TY - GEN
AU - N., N.
ID - 42321
TI - Kindergarten Allocation through Matching Mechanisms
ER -
TY - GEN
AU - N., N.
ID - 42309
TI - Faire Profitverteilung in Energienetzwerken - eine spieltheoretische Analyse von Microgrids
ER -
TY - GEN
AU - N., N.
ID - 42311
TI - "First-Party-Content" auf zweiseitigen Märkten
ER -
TY - GEN
AU - N., N.
ID - 42314
TI - Stability in many-to-many matchings with contracts
ER -
TY - GEN
AU - N., N.
ID - 42313
TI - Preissetzungsstrategien für Neuprodukte
ER -
TY - GEN
AU - N., N.
ID - 42310
TI - Co-opetition in Two-Sided Markets
ER -
TY - GEN
AU - N., N.
ID - 42312
TI - Matching mit Minderheiten
ER -
TY - GEN
AU - N., N.
ID - 42316
TI - Piracy and Visioning
ER -
TY - GEN
AU - N., N.
ID - 42303
TI - Revenue Sharing Contracts: Horizontale Koordination in der E-Commerce-Logistik
ER -
TY - GEN
AU - N., N.
ID - 45236
TI - Design and Implementation of a Crowd-based Prototype Validation Platform
ER -
TY - GEN
AU - N., N.
ID - 45237
TI - Model-based Continuous Experimentation for Software Product Prototypes
ER -
TY - GEN
AU - N., N.
ID - 45239
TI - Lightweight Process Engine for Situation-specific Development of Business Models for Digital Platforms
ER -
TY - GEN
AU - N., N.
ID - 45240
TI - Development and Evaluation of a Multi Platform Approach for Augmented Reality Product Configuration
ER -
TY - GEN
AU - N., N.
ID - 45238
TI - Model-based Feature Backlog Synchronization for Dual-Track Development Methods
ER -
TY - JOUR
AB - Heat-assisted forming processes are becoming increasingly important in the manufacturing of sheet metal parts for body-in-white applications. However, the non-isothermal nature of these processes leads to challenges in evaluating the forming limits, since established methods such as Forming Limit Curves (FLCs) only allow the assessment of critical forming strains for steady temperatures. For this reason, a temperature-dependent extension of the well-established GISSMO (Generalized Incremental Stress State Dependent Damage Model) fracture indicator framework is developed by the authors to predict forming failures under non-isothermal conditions. In this paper, a general approach to combine several isothermal FLCs within the temperature-extended GISSMO model into a temperature-dependent forming limit surface is investigated. The general capabilities of the model are tested in a coupled thermo-mechanical FEA using the example of warm forming of an AA5182-O sheet metal cross-die cup. The obtained results are then compared with state of the art of evaluation methods. By taking the strain and temperature path into account, GISSMO predicts greater drawing depths by up to 20% than established methods. In this way the forming and so the lightweight potential of sheet metal parts can by fully exploited. Moreover, the risk and locus of failure can be evaluated directly on the part geometry by a contour plot. An additional advantage of the GISSMO model is the applicability for low triaxialities as well as the possibility to predict the materials behavior beyond necking up to ductile fracture.
AU - Camberg, Alan Adam
AU - Erhart, Tobias
AU - Tröster, Thomas
ID - 24009
JF - Materials
SN - 1996-1944
TI - A Generalized Stress State and Temperature Dependent Damage Indicator Framework for Ductile Failure Prediction in Heat-Assisted Forming Operations
ER -
TY - GEN
AU - Anonymous, Anonymous
ID - 45254
TI - Device-Independent Security Proofs Via Entropy Accumulation
ER -
TY - CHAP
AU - Saad, Nadia
ID - 42253
T2 - Methoden der Darstellung und Analyse interreligiöser Diskurse
TI - David und Salomo im Koran: ein Komparativ-theologischer Ansatz
VL - 1
ER -
TY - JOUR
AU - Mir Sadri, Seyedeh Saeideh
AU - Nasiri, Mansour
ID - 42256
IS - 2
JF - Philosophy East and West
TI - Reading Iqbal in the Light of Kierkegaard; towards an Existentialist Approach to Islam
VL - 71
ER -
TY - JOUR
AU - Mir Sadri, Seyedeh Saeideh
ID - 42257
IS - 1
JF - Amos-international
TI - Fratelli e sorelle tutti. Die Sozialenzyklika aus islamischer Sicht
VL - 15
ER -
TY - CHAP
AU - Eikermann, Larissa
ED - Ströter-Bender, Jutta
ID - 45275
SN - 9783828876668
T2 - Das Erbe der Kinder: Provenienzforschung und Sammlungsgeschichte von Kinder- und Jugendzeichnungen: Museen, Archive, private Kollektionen und "verschwundene Sammlungen" = The children's heritage: provenance research and the history of children's and youth drawings collections: museums, archives, private holdings and "lost collections"
TI - "Ein altes Familientalent" - Kinderzeichnungen aus der Familie der Brüder Grimm (1. Hälfte 19. Jh.) in der Grimm-Sammlung der Stadt Kassel. Germany
VL - Bd. 30
ER -
TY - CHAP
AU - Eikermann, Larissa
ED - Ströter-Bender, Jutta
ID - 45276
SN - 9783828876668
T2 - Das Erbe der Kinder: Provenienzforschung und Sammlungsgeschichte von Kinder- und Jugendzeichnungen: Museen, Archive, private Kollektionen und "verschwundene Sammlungen" = The children's heritage: provenance research and the history of children's and youth drawings collections: museums, archives, private holdings and "lost collections"
TI - Children´s drawings on Pippi & Co. - A visit to the Astrid Lindgren Archive in the Royal Library of Stockholm. Sweden
VL - Bd. 30
ER -
TY - CHAP
AU - Kamcili-Yildiz, Naciye
ED - Espelage, Christian
ED - Mohagheghi, Hamideh
ED - Schober, Michael
ID - 42096
T2 - Interreligiöse Öffnung durch Begegnung. Grundlagen - Erfahrungen - Perspektiven im Kontext des christlich-islamischen Dialogs
TI - Begegnungslernen in den Kerncurricula des islamischen Religionsunterrichts
VL - 43
ER -
TY - BOOK
AU - Kamcili-Yildiz, Naciye
ID - 42058
SN - 973-3830942958
TI - Zwischen Glaubensvermittlung und Reflexivität: Eine quantitative Studie zu professionellen Kompetenzen von islamischen ReligionslehrerInnen
VL - 682
ER -
TY - JOUR
AU - Mustafa, Abdul Rahman
ID - 42265
IS - 8
JF - Political Theology
TI - Supernatural, Unnatural, Queer: Gratitude and Nature in Islamic Political Theology
VL - 22
ER -
TY - JOUR
AU - Aghaei Abrandabadi, Seyed Ali
AU - Marx, Michel
ID - 42224
IS - 1
JF - Journal of Iranian National Museum
TI - Carbon Dating of Seven Parchment Qurʾān Manuscripts and One Syriac Bible of the National Museum of Iran
VL - 2
ER -
TY - JOUR
AU - Ghaffar, Zishan
ID - 42341
IS - 2
JF - Der Islam
TI - Kontrafaktische Intertextualität im Koran und die exegetische Tradition des syrischen Christentums
VL - 98
ER -
TY - CHAP
AU - Tatari, Muna
ED - Khalfaoui, Mouez
ED - Ehret, Jean
ID - 37120
SN - 9783451391439
T2 - Islamische Theologie in Deutschland. Ein Modell für Europa und die Welt
TI - Islamische systematische Theologie in Deutschland: Konturen eines jungen Faches
ER -
TY - BOOK
AU - Tatari, Muna
AU - von Stosch, Klaus
ID - 37035
SN - 3451389649
TI - Prophetin - Jungfrau - Mutter: Maria im Koran
ER -
TY - GEN
AU - Nassery, Idris
ID - 42479
T2 - Frankfurter Allgemeine Zeitung
TI - Die unerwünschte Empfehlung, Hybris: Woran der Westen in Afghanistan tatsächlich gescheitert ist
ER -
TY - JOUR
AU - Kulgemeyer, Christoph
AU - Kempin, Maren
AU - Weißbach, Anna
AU - Borowski, Andreas
AU - Buschhüter, David
AU - Enkrott, Patrick
AU - Reinhold, Peter
AU - Riese, Josef
AU - Schecker, Horst
AU - Schröder, Jan
AU - Vogelsang, Christoph
ID - 45177
IS - 18
JF - International Journal of Science Education
KW - Education
SN - 0950-0693
TI - Exploring the impact of pre-service science teachers’ reflection skills on the development of professional knowledge during a field experience
VL - 43
ER -
TY - CONF
AU - Große-Heilmann, Rike Isabel
AU - Burde, Jan-Philipp
AU - Riese, Josef
AU - Schubatzky, Thomas
AU - Weiler, David
ID - 45407
T2 - PhyDid B-Didaktik der Physik-Beiträge zur DPG-Frühjahrstagung 2021
TI - Erwerb und Messung physikdidaktischer Kompetenzen zum Einsatz digitaler Medien
ER -
TY - CONF
AU - Weiler, David
AU - Burde, Jan-Philipp
AU - Große-Heilmann, Rike Isabel
AU - Lachner, Andreas
AU - Riese, Josef
AU - Schubatzky, Thomas
ID - 45408
T2 - PhyDid B-Didaktik der Physik-Beiträge zur DPG-Frühjahrstagung 2021
TI - Entwicklung eines Seminars zur Förderung des Konzeptverständnisses mittels digitaler Medien
ER -
TY - CHAP
AU - Haghani Fazl, Mohammad
ED - Grössl, Johannes
ED - von Stosch, Klaus
ID - 45436
T2 - Impeccability and Temptation: Understanding Christ's Divine and Human Will
TI - The Scope of ‘iṣma and Qur’anic Evidence
ER -
TY - JOUR
AU - Hein, Maxwell
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 41511
IS - 7
JF - Materialwissenschaft und Werkstofftechnik
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - Condensed Matter Physics
KW - General Materials Science
SN - 0933-5137
TI - Additively processed TiAl6Nb7 alloy for biomedical applications
VL - 52
ER -
TY - JOUR
AB -
Purpose
The currently existing restrictions regarding the deployment of additively manufactured components because of poor surface roughness, porosity and residual stresses as well as their influence on the low-cycle fatigue (LCF) strength are addressed in this paper.
Design/methodology/approach
This study aims to evaluating the effect of different pre- and post-treatments on the LCF strength of additively manufactured 316L parts. Therefore, 316L specimens manufactured by laser powder bed fusion were examined in their as-built state as well as after grinding, or coating with regard to the surface roughness, residual stresses and LCF strength. To differentiate between topographical effects and residual stress-related phenomena, stress-relieved 316L specimens served as a reference throughout the investigations. To enable an alumina coating of the 316L components, atmospheric plasma spraying was used, and the near-surface residual stresses and the surface roughness are measured and investigated.
Findings
The results have shown that the applied pre- and post-treatments such as stress-relief heat treatment, grinding and alumina coating have each led to an increase in LCF strength of the 316L specimens. In contrast, the non-heat-treated specimens predominantly exhibited coating delamination.
Originality/value
To the best of the authors’ knowledge, this is the first study of the correlation between the LCF behavior of additively manufactured uncoated 316L specimens in comparison with additively manufactured 316L specimens with an alumina coating.
AU - Garthe, Kai-Uwe
AU - Hoyer, Kay-Peter
AU - Hagen, Leif
AU - Tillmann, Wolfgang
AU - Schaper, Mirko
ID - 41507
IS - 5
JF - Rapid Prototyping Journal
KW - Industrial and Manufacturing Engineering
KW - Mechanical Engineering
SN - 1355-2546
TI - Correlation between pre- and post-treatments of additively manufactured 316L parts and the resulting low cycle fatigue behavior
VL - 28
ER -
TY - JOUR
AB - Processing aluminum alloys employing powder bed fusion of metals (PBF-LB/M) is becoming more attractive for the industry, especially if lightweight applications are needed. Unfortunately, high-strength aluminum alloys such as AA7075 are prone to hot cracking during PBF-LB/M, as well as welding. Both a large solidification range promoted by the alloying elements zinc and copper and a high thermal gradient accompanied with the manufacturing process conditions lead to or favor hot cracking. In the present study, a simple method for modifying the powder surface with titanium carbide nanoparticles (NPs) as a nucleating agent is aimed. The effect on the microstructure with different amounts of the nucleating agent is shown. For the aluminum alloy 7075 with 2.5 ma% titanium carbide nanoparticles, manufactured via PBF-LB/M, crack-free samples with a refined microstructure having no discernible melt pool boundaries and columnar grains are observed. After using a two-step ageing heat treatment, ultimate tensile strengths up to 465 MPa and an 8.9% elongation at break are achieved. Furthermore, it is demonstrated that not all nanoparticles used remain in the melt pool during PBF-LB/M.
AU - Heiland, Steffen
AU - Milkereit, Benjamin
AU - Hoyer, Kay-Peter
AU - Zhuravlev, Evgeny
AU - Kessler, Olaf
AU - Schaper, Mirko
ID - 41506
IS - 23
JF - Materials
KW - General Materials Science
SN - 1996-1944
TI - Requirements for Processing High-Strength AlZnMgCu Alloys with PBF-LB/M to Achieve Crack-Free and Dense Parts
VL - 14
ER -
TY - JOUR
AB - Implants often overtake body function just for a certain time and remain as an unnecessary foreign body or have to be removed. Thus, resorbable implants are highly beneficial to reduce patient burden. Besides established materials, Iron-(Fe)-based alloys are in focus due to superior mechanical properties and good biocompatibility. However, their degradation rate needs to be increased. Phases with high electrochemical potential could promote the dissolution of residual material based on the galvanic coupling. Silver (Ag) is promising due to its high electrochemical potential (+0.8 V vs. SHE), immiscibility with Fe, biocompatibility, and anti-bacterial properties. But to prevent adverse consequences the Ag-particles, remaining after dissolution of the matrix, need to dissolve. Thus, a bioresorbable Ag-alloy is required. Regarding the electrochemical potential and degradation behavior of binary alloys, Cerium (Ce) and Lanthanum (La) are well-suited considering their biocompatibility and antibacterial behavior. Accordingly, this research addresses AgCe and AgCeLa alloys as additives for Fe-based materials with adapted degradation behavior. Furthermore, degradable Ag-alloys combined with inert implant materials could enable the controlled release of antibacterial active Ag-ions.
AU - Krüger, Jan Tobias
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 24790
JF - Materials Letters
SN - 0167-577X
TI - Bioresorbable AgCe and AgCeLa alloys for adapted Fe-based implants
VL - 306
ER -
TY - JOUR
AU - Tillmann, Wolfgang
AU - Lopes Dias, Nelson Filipe
AU - Franke, Carlo
AU - Kokalj, David
AU - Stangier, Dominic
AU - Filor, Viviane
AU - Mateus-Vargas, Rafael Hernán
AU - Oltmanns, Hilke
AU - Kietzmann, Manfred
AU - Meißner, Jessica
AU - Hein, Maxwell
AU - Pramanik, Sudipta
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
AU - Nienhaus, Alexander
AU - Thomann, Carl Arne
AU - Debus, Jörg
ID - 41516
JF - Surface and Coatings Technology
KW - Materials Chemistry
KW - Surfaces
KW - Coatings and Films
KW - Surfaces and Interfaces
KW - Condensed Matter Physics
KW - General Chemistry
SN - 0257-8972
TI - Tribo-mechanical properties and biocompatibility of Ag-containing amorphous carbon films deposited onto Ti6Al4V
VL - 421
ER -
TY - JOUR
AU - Andreiev, Anatolii
AU - Hoyer, Kay-Peter
AU - Dula, Dimitri
AU - Hengsbach, Florian
AU - Grydin, Olexandr
AU - Frolov, Yaroslav
AU - Schaper, Mirko
ID - 41512
JF - Materials Science and Engineering: A
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - Condensed Matter Physics
KW - General Materials Science
SN - 0921-5093
TI - Laser beam melting of functionally graded materials with application-adapted tailoring of magnetic and mechanical performance
VL - 822
ER -
TY - JOUR
AU - Pramanik, Sudipta
AU - Andreiev, Anatolii
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 41510
JF - International Journal of Fatigue
KW - Industrial and Manufacturing Engineering
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - General Materials Science
KW - Modeling and Simulation
SN - 0142-1123
TI - Quasi in-situ analysis of fracture path during cyclic loading of double-edged U notched additively manufactured FeCo alloy
VL - 153
ER -
TY - JOUR
AU - Krüger, Jan Tobias
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 41509
JF - Materials Letters
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - Condensed Matter Physics
KW - General Materials Science
SN - 0167-577X
TI - Bioresorbable AgCe and AgCeLa alloys for adapted Fe-based implants
VL - 306
ER -
TY - JOUR
AU - Andreiev, Anatolii
AU - Hoyer, Kay-Peter
AU - Dula, Dimitri
AU - Hengsbach, Florian
AU - Haase, Michael
AU - Gierse, Jan
AU - Zimmer, Detmar
AU - Tröster, Thomas
AU - Schaper, Mirko
ID - 23898
JF - Journal of Materials Processing Technology
SN - 0924-0136
TI - Soft-magnetic behavior of laser beam melted FeSi3 alloy with graded cross-section
ER -
TY - JOUR
AB - AbstractWithin this research, the multiscale microstructural evolution before and after the tensile test of a FeCo alloy is addressed. X-ray µ-computer tomography (CT), electron backscattered diffraction (EBSD), and transmission electron microscopy (TEM) are employed to determine the microstructure on different length scales. Microstructural evolution is studied by performing EBSD of the same area before and after the tensile test. As a result, $$\langle$$
⟨
001$$\rangle$$
⟩
||TD, $$\langle$$
⟨
011$$\rangle$$
⟩
||TD are hard orientations and $$\langle$$
⟨
111$$\rangle$$
⟩
||TD is soft orientations for deformation accommodation. It is not possible to predict the deformation of a single grain with the Taylor model. However, the Taylor model accurately predicts the orientation of all grains after deformation. {123}$$\langle$$
⟨
111$$\rangle$$
⟩
is the most active slip system, and {112}$$\langle$$
⟨
111$$\rangle$$
⟩
is the least active slip system. Both EBSD micrographs show grain subdivision after tensile testing. TEM images show the formation of dislocation cells. Correlative HRTEM images show unresolved lattice fringes at dislocation cell boundaries, whereas resolved lattice fringes are observed at dislocation cell interior. Since Schmid’s law is unable to predict the deformation behavior of grains, the boundary slip transmission accurately predicts the grain deformation behavior.
AU - Pramanik, Sudipta
AU - Tasche, Lennart
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 41517
IS - 11
JF - Journal of Materials Engineering and Performance
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - General Materials Science
SN - 1059-9495
TI - Correlation between Taylor Model Prediction and Transmission Electron Microscopy-Based Microstructural Investigations of Quasi-In Situ Tensile Deformation of Additively Manufactured FeCo Alloy
VL - 30
ER -
TY - JOUR
AB - The addition of Ag to amorphous carbon (a-C) films is highly effective in tailoring the tribo-mechanical properties and biocompatibility. For biomedical applications, Ag-containing a-C (a-C:Ag) represents a promising film material for improving the biofunctional surface properties of Ti-based alloys. In a sputtering process, a-C:Ag films, with Ag contents up to 7.5 at.%, were deposited with a chemically graded TixCy interlayer onto Ti6Al4V. The tribo-mechanical and biocompatible properties of a-C:Ag were evaluated. The influence of the Ag content on these properties was analyzed and compared to those of uncoated Ti6Al4V.
Raman spectroscopy reveals that the amount of incorporated Ag does not induce significant structural changes in the disordered network, only a reduced number of vacancies and sp3-coordinated C bonds within the sp2-dominant a-C network is assigned to the films with high Ag concentration. With increasing Ag content, stresses, hardness, and elastic modulus decrease from (2.02 ± 0.07) to (1.15 ± 0.03) GPa, from (17.4 ± 1.5) to (13.4 ± 0.9) GPa, and from (171.8 ± 8.1) to (138.5 ± 5.8) GPa, respectively. In tribometer tests, the friction behavior against Al2O3 in lubricated condition with a simulated-body-fluid-based lubricant is not affected by the Ag concentration, but the Al2O3 counterpart wear is reduced for all a-C:Ag films compared to a-C. The friction against ultra-high-molecular-weight polyethylene (UHMWPE) decreases continuously with increasing Ag concentration and the counterpart wear is lower at higher Ag contents. Compared to a-C:Ag, Ti6Al4V demonstrates lower friction against UHMWPE and higher friction against Al2O3. The a-C:Ag films are not exposed to abrasion by Al2O3 or pronounced material transfer of UHMWPE. The hardness difference and chemical affinity between the friction partners are decisive for the tribological behavior of a-C:Ag. Compared to Ti6Al4V, the a-C:Ag films show antibacterial activity against Staphylococcus aureus, while the proliferation of osteoblast-like cells is reduced by Ag.
AU - Tillmann, Wolfgang
AU - Lopes Dias, Nelson Filipe
AU - Franke, Carlo
AU - Kokalj, David
AU - Stangier, Dominic
AU - Filor, Viviane
AU - Mateus-Vargas, Rafael Hernán
AU - Oltmanns, Hilke
AU - Kietzmann, Manfred
AU - Meißner, Jessica
AU - Hein, Maxwell
AU - Pramanik, Sudipta
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
AU - Nienhaus, Alexander
AU - Thomann, Carl Arne
AU - Debus, Jörg
ID - 24243
JF - Surface and Coatings Technology
SN - 0257-8972
TI - Tribo-mechanical properties and biocompatibility of Ag-containing amorphous carbon films deposited onto Ti6Al4V
ER -
TY - JOUR
AB - Aluminium steel clad materials have high potential for industrial applications. Their mechanical properties are governed by an intermetallic layer, which forms upon heat treatment at the Al-Fe interface. Transmission electron microscopy was employed to identify the phases present at the interface by selective area electron diffraction and energy dispersive spectroscopy. Three phases were identified: orthorhombic Al5Fe2, monoclinic Al13Fe4 and cubic Al19Fe4MnSi2. An effective interdiffusion coefficient dependent on concentration was determined according to the Boltzmann–Matano method. The highest value of the interdiffusion coefficient was reached at the composition of the intermetallic phases. Afterwards, the process of diffusion considering the evaluated interdiffusion coefficient was simulated using the finite element method. Results of the simulations revealed that growth of the intermetallic phases proceeds preferentially in the direction of aluminium.
AU - Křivská, Barbora
AU - Šlapáková, Michaela
AU - Veselý, Jozef
AU - Kihoulou, Martin
AU - Fekete, Klaudia
AU - Minárik, Peter
AU - Králík, Rostislav
AU - Grydin, Olexandr
AU - Stolbchenko, Mykhailo
AU - Schaper, Mirko
ID - 29815
IS - 24
JF - Materials
KW - General Materials Science
SN - 1996-1944
TI - Intermetallic Phases Identification and Diffusion Simulation in Twin-Roll Cast Al-Fe Clad Sheet
VL - 14
ER -
TY - JOUR
AB - Laser beam melting (LBM) is an advanced manufacturing technology providing
special features and the possibility to produce complex and individual parts directly
from a CAD model. TiAl6V4 is the most common used titanium alloy particularly
in biomedical applications. TiAl6Nb7 shows promising improvements especially
regarding biocompatible properties due to the substitution of the hazardous
vanadium. This work focuses on the examination of laser beam melted TiAl6Nb7.
For microstructural investigation scanning electron microscopy including energydispersive
x-ray spectroscopy as well as electron backscatter diffraction are utilized.
The laser beam melted related acicular microstructure as well as the corresponding
mechanical properties, which are determined by hardness measurements
and tensile tests, are investigated. The laser beam melted alloy meets,
except of breaking elongation A, the mechanical demands like ultimate tensile
strength Rm, yield strength Rp0.2, Vickers hardness HV of international standard
ISO 5832-11. Next steps contain comparison between TiAl6Nb7 and TiAl6V4 in
different conditions. Further investigations aim at improving mechanical properties
of TiAl6Nb7 by heat treatments and assessment of their influence on the microstructure
as well as examination regarding the corrosive behavior in human bodylike
conditions.
AU - Hein, Maxwell
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 24086
JF - Materialwissenschaft und Werkstofftechnik
KW - Laser beam melting
KW - titanium alloy
KW - TiAl6Nb7
KW - biomedical engineering
KW - implants
SN - 0933-5137
TI - Additively processed TiAl6Nb7 alloy for biomedical applications
VL - 52
ER -
TY - JOUR
AU - Cieslar, Miroslav
AU - Králík, Rostislav
AU - Bajtošová, Lucia
AU - Křivská, Barbora
AU - Hájek, Michal
AU - Belejová, Sára
AU - Grydin, Olexandr
AU - Stolbchenko, Mykhailo
AU - Schaper, Mirko
ID - 29813
IS - S2
JF - Microscopy and Microanalysis
KW - Instrumentation
SN - 1431-9276
TI - High Temperature Annealing of Twin-Roll Cast Al-Li-Based Alloy Studied by In-situ SEM and STEM
VL - 27
ER -
TY - JOUR
AU - Krüger, Jan Tobias
AU - Hoyer, Kay-Peter
AU - Filor, Viviane
AU - Pramanik, Sudipta
AU - Kietzmann, Manfred
AU - Meißner, Jessica
AU - Schaper, Mirko
ID - 41514
JF - Journal of Alloys and Compounds
KW - Materials Chemistry
KW - Metals and Alloys
KW - Mechanical Engineering
KW - Mechanics of Materials
SN - 0925-8388
TI - Novel AgCa and AgCaLa alloys for Fe-based bioresorbable implants with adapted degradation
VL - 871
ER -
TY - JOUR
AU - Křivská, Barbora
AU - Šlapáková, Michaela
AU - Minárik, Peter
AU - Fekete, Klaudia
AU - Králík, Rostislav
AU - Stolbchenko, Mykhailo
AU - Schaper, Mirko
AU - Grydin, Olexandr
ID - 29814
IS - S2
JF - Microscopy and Microanalysis
KW - Instrumentation
SN - 1431-9276
TI - Intermetallic Phase Growth in Al-steel Clad Strip during In-situ Heating in TEM
VL - 27
ER -
TY - JOUR
AU - Pramanik, Sudipta
AU - Tasche, Lennart
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 41515
JF - Additive Manufacturing
KW - Industrial and Manufacturing Engineering
KW - Engineering (miscellaneous)
KW - General Materials Science
KW - Biomedical Engineering
SN - 2214-8604
TI - Investigating the microstructure of an additively manufactured FeCo alloy: an electron microscopy study
VL - 46
ER -
TY - JOUR
AU - Camberg, Alan Adam
AU - Andreiev, Anatolii
AU - Pramanik, Sudipta
AU - Hoyer, Kay-Peter
AU - Tröster, Thomas
AU - Schaper, Mirko
ID - 27700
JF - Materials Science and Engineering: A
SN - 0921-5093
TI - Strength enhancement of AlMg sheet metal parts by rapid heating and subsequent cold die stamping of severely cold-rolled blanks
ER -
TY - JOUR
AB - AbstractWithin this research, the multiscale microstructural evolution before and after the tensile test of a FeCo alloy is addressed. X-ray µ-computer tomography (CT), electron backscattered diffraction (EBSD), and transmission electron microscopy (TEM) are employed to determine the microstructure on different length scales. Microstructural evolution is studied by performing EBSD of the same area before and after the tensile test. As a result, $$\langle$$
⟨
001$$\rangle$$
⟩
||TD, $$\langle$$
⟨
011$$\rangle$$
⟩
||TD are hard orientations and $$\langle$$
⟨
111$$\rangle$$
⟩
||TD is soft orientations for deformation accommodation. It is not possible to predict the deformation of a single grain with the Taylor model. However, the Taylor model accurately predicts the orientation of all grains after deformation. {123}$$\langle$$
⟨
111$$\rangle$$
⟩
is the most active slip system, and {112}$$\langle$$
⟨
111$$\rangle$$
⟩
is the least active slip system. Both EBSD micrographs show grain subdivision after tensile testing. TEM images show the formation of dislocation cells. Correlative HRTEM images show unresolved lattice fringes at dislocation cell boundaries, whereas resolved lattice fringes are observed at dislocation cell interior. Since Schmid’s law is unable to predict the deformation behavior of grains, the boundary slip transmission accurately predicts the grain deformation behavior.
AU - Pramanik, Sudipta
AU - Tasche, Lennart
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 24090
JF - Journal of Materials Engineering and Performance
SN - 1059-9495
TI - Correlation between Taylor Model Prediction and Transmission Electron Microscopy-Based Microstructural Investigations of Quasi-In Situ Tensile Deformation of Additively Manufactured FeCo Alloy
ER -
TY - JOUR
AB -
Purpose
The currently existing restrictions regarding the deployment of additively manufactured components because of poor surface roughness, porosity and residual stresses as well as their influence on the low-cycle fatigue (LCF) strength are addressed in this paper.
Design/methodology/approach
This study aims to evaluating the effect of different pre- and post-treatments on the LCF strength of additively manufactured 316L parts. Therefore, 316L specimens manufactured by laser powder bed fusion were examined in their as-built state as well as after grinding, or coating with regard to the surface roughness, residual stresses and LCF strength. To differentiate between topographical effects and residual stress-related phenomena, stress-relieved 316L specimens served as a reference throughout the investigations. To enable an alumina coating of the 316L components, atmospheric plasma spraying was used, and the near-surface residual stresses and the surface roughness are measured and investigated.
Findings
The results have shown that the applied pre- and post-treatments such as stress-relief heat treatment, grinding and alumina coating have each led to an increase in LCF strength of the 316L specimens. In contrast, the non-heat-treated specimens predominantly exhibited coating delamination.
Originality/value
To the best of the authors’ knowledge, this is the first study of the correlation between the LCF behavior of additively manufactured uncoated 316L specimens in comparison with additively manufactured 316L specimens with an alumina coating.
AU - Garthe, Kai-Uwe
AU - Hoyer, Kay-Peter
AU - Hagen, Leif
AU - Tillmann, Wolfgang
AU - Schaper, Mirko
ID - 27509
JF - Rapid Prototyping Journal
SN - 1355-2546
TI - Correlation between pre- and post-treatments of additively manufactured 316L parts and the resulting low cycle fatigue behavior
ER -
TY - JOUR
AB - Resorbable implants are highly beneficial to reduce patient burden since they need not be removed after a defined period. Currently, magnesium (Mg) and polymers are being applied as bioresorbable materials. However, for some applications the insufficient mechanical properties and high degradation rate of Mg cause the need for new materials. Iron (Fe)-based alloys are promising due to their biocompatibility and good mechanical properties, but their degradation rate is too low and needs to be adapted eg. via alloying with manganese (Mn). Besides, phases with high electrochemical potential lead to increased degradation of residual material with lower potential based on the galvanic coupling. Here, silver (Ag) is promising for the formation of such phases due to its high electrochemical potential (+0.8 V vs. SHE), immiscibility with Fe, biocompatibility, and anti-bacterial properties. Since remaining silver particles can lead to adverse consequences as thrombosis, these particles need to dissolve after the matrix material. Thus a silver alloy with high electrochemical potential, biocompatibility, and adjusted degradation behavior is required as an additive for iron-based bioresorbable materials. Several silver alloying systems are possible, but regarding the electrochemical potential and degradation behavior of binary alloys, calcium (Ca) and lanthanum (La) are best-suited considering their biocompatibility. Accordingly, this research addresses AgCa and AgCaLa alloys as additives for iron-based degradable materials with adapted degradation behavior.
AU - Krüger, Jan Tobias
AU - Hoyer, Kay-Peter
AU - Filor, Viviane
AU - Pramanik, Sudipta
AU - Kietzmann, Manfred
AU - Meißner, Jessica
AU - Schaper, Mirko
ID - 24087
JF - Journal of Alloys and Compounds
SN - 0925-8388
TI - Novel AgCa and AgCaLa alloys for Fe-based bioresorbable implants with adapted degradation
ER -
TY - JOUR
AB - Implementing the concept of mixed construction in modern automotive engineering requires the joining of sheet metal or extruded profiles with cast components made from different materials. As weight reduction is desired, these cast components are usually made from high-strength aluminium alloys of the Al-Si (Mn, Mg) system, which have limited weldability. The mechanical joinability of the cast components depends on their ductility, which is influenced by the microstructure. High-strength cast aluminium alloys have relatively low ductility, which leads to cracking of the joints. This limits the range of applications for cast aluminium alloys. In this study, an aluminium alloy of the Al-Si system AlSi9 is used to investigate relationships between solidification conditions during the sand casting process, microstructure, mechanical properties, and joinability. The demonstrator is a stepped plate with a minimum thickness of 2.0 mm and a maximum thickness of 4.0 mm, whereas the thickness difference between neighbour steps amounts to 0.5 mm. During casting trials, the solidification rates for different plate steps were measured. The microscopic investigations reveal a correlation between solidification rates and microstructure parameters such as secondary dendrite arm spacing. Furthermore, mechanical properties and the mechanical joinability are investigated.
AU - Neuser, Moritz
AU - Grydin, Olexandr
AU - Andreiev, Anatolii
AU - Schaper, Mirko
ID - 23913
JF - Metals
SN - 2075-4701
TI - Effect of Solidification Rates at Sand Casting on the Mechanical Joinability of a Cast Aluminium Alloy
ER -
TY - JOUR
AB - AbstractLaser surface treatment of metals is one option to improve their properties for adhesive bonding. In this paper, a pulsed YVO4 Laser source with a wavelength of 1064 nm and a maximum power of 25 W was utilized to increase the surface area of the steel HCT490X in order to improve its bonding properties with a carbon fibre reinforced polymer (CFRP). Investigated was the influence of the scanning speed of the laser source on the bonding properties. For this purpose, the steel surfaces were ablated at a scanning speed between 1500 and 4500 mm/s. Afterwards the components were bonded with the adhesive HexBond™ 677. After lap shear tests were carried out on the specimen, the surfaces were inspected using scanning electron microscopy (SEM). The experiments revealed that the bonding quality can be improved with a high scanning speed, even when the surface is not completely ablated.
AU - Voswinkel, Dietrich
AU - Kloidt, D.
AU - Grydin, Olexandr
AU - Schaper, Mirko
ID - 24565
IS - 2
JF - Production Engineering
SN - 0944-6524
TI - Time efficient laser modification of steel surfaces for advanced bonding in hybrid materials
VL - 15
ER -
TY - JOUR
AU - Engelkemeier, Katja
AU - Sun, Aijia
AU - Voswinkel, Dietrich
AU - Grydin, Olexandr
AU - Schaper, Mirko
AU - Bremser, Wolfgang
ID - 24566
JF - ChemElectroChem
SN - 2196-0216
TI - Zinc Anodizing: Structural Diversity of Anodic Zinc Oxide Controlled by the Type of Electrolyte
ER -
TY - JOUR
AU - Andreiev, Anatolii
AU - Hoyer, Kay-Peter
AU - Dula, Dimitri
AU - Hengsbach, Florian
AU - Grydin, Olexandr
AU - Frolov, Yaroslav
AU - Schaper, Mirko
ID - 23897
JF - Materials Science and Engineering: A
SN - 0921-5093
TI - Laser beam melting of functionally graded materials with application-adapted tailoring of magnetic and mechanical performance
ER -
TY - JOUR
AU - Pramanik, Sudipta
AU - Andreiev, Anatolii
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 23911
JF - International Journal of Fatigue
SN - 0142-1123
TI - Quasi in-situ analysis of fracture path during cyclic loading of double-edged U notched additively manufactured FeCo alloy
ER -
TY - JOUR
AU - Pramanik, Sudipta
AU - Tasche, Lennart
AU - Hoyer, Kay-Peter
AU - Schaper, Mirko
ID - 24088
JF - Additive Manufacturing
SN - 2214-8604
TI - Investigating the microstructure of an additively manufactured FeCo alloy: an electron microscopy study
ER -