@article{36327,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>With an innovative optical characterization method, using high-temperature digital image correlation in combination with thermal imaging, the local change in strain and change in temperature could be determined during thermo-mechanical treatment of flat steel specimens. With data obtained by this optical method, the transformation kinetics for every area of interest along the whole measuring length of a flat specimen could be analyzed by the generation of dilatation curves. The benefit of this innovative optical characterization method compared to a dilatometer test is that the experimental effort for the design of a tailored component could be strongly reduced to the investigation of only a few tailored thermo-mechanical processed specimens. Due to the implementation of a strain and/or temperature gradient within the flat specimen, less metallographic samples are prepared for hardness analysis and analysis of the microstructural composition by scanning electron microscopy to investigate the influence of different process parameters. Compared to performed dilatometer tests in this study, the optical method obtained comparable results for the transformation start and end temperatures. For the final design of a part with tailored properties, the optical method is suitable for a time-efficient material characterization.</jats:p>
                <jats:p><jats:bold>Graphical Abstract</jats:bold></jats:p>}},
  author       = {{Reitz, Alexander and Grydin, Olexandr and Schaper, Mirko}},
  issn         = {{1073-5623}},
  journal      = {{Metallurgical and Materials Transactions A}},
  keywords     = {{Metals and Alloys, Mechanics of Materials, Condensed Matter Physics}},
  number       = {{8}},
  pages        = {{3125--3142}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Optical Detection of Phase Transformations in Steels: An Innovative Method for Time-Efficient Material Characterization During Tailored Thermo-mechanical Processing of a Press Hardening Steel}}},
  doi          = {{10.1007/s11661-022-06732-z}},
  volume       = {{53}},
  year         = {{2022}},
}

@article{29196,
  abstract     = {{In biomedical engineering, laser powder bed fusion is an advanced manufacturing technology, which enables, for example, the production of patient-customized implants with complex geometries. Ti-6Al-7Nb shows promising improvements, especially regarding biocompatibility, compared with other titanium alloys. The biocompatible features are investigated employing cytocompatibility and antibacterial examinations on Al2O3-blasted and untreated surfaces. The mechanical properties of additively manufactured Ti-6Al-7Nb are evaluated in as-built and heat-treated conditions. Recrystallization annealing (925 °C for 4 h), β annealing (1050 °C for 2 h), as well as stress relieving (600 °C for 4 h) are applied. For microstructural investigation, scanning and transmission electron microscopy are performed. The different microstructures and the mechanical properties are compared. Mechanical behavior is determined based on quasi-static tensile tests and strain-controlled low cycle fatigue tests with total strain amplitudes εA of 0.35%, 0.5%, and 0.8%. The as-built and stress-relieved conditions meet the mechanical demands for the tensile properties of the international standard ISO 5832-11. Based on the Coffin–Manson–Basquin relation, fatigue strength and ductility coefficients, as well as exponents, are determined to examine fatigue life for the different conditions. The stress-relieved condition exhibits, overall, the best properties regarding monotonic tensile and cyclic fatigue behavior.</jats:p>}},
  author       = {{Hein, Maxwell and Kokalj, David and Lopes Dias, Nelson Filipe and Stangier, Dominic and Oltmanns, Hilke and Pramanik, Sudipta and Kietzmann, Manfred and Hoyer, Kay-Peter and Meißner, Jessica and Tillmann, Wolfgang and Schaper, Mirko}},
  issn         = {{2075-4701}},
  journal      = {{Metals}},
  keywords     = {{General Materials Science, Metals and Alloys, laser powder bed fusion, Ti-6Al-7Nb, titanium alloy, biomedical engineering, low cycle fatigue, microstructure, nanostructure}},
  number       = {{1}},
  publisher    = {{MDPI AG}},
  title        = {{{Low Cycle Fatigue Performance of Additively Processed and Heat-Treated Ti-6Al-7Nb Alloy for Biomedical Applications}}},
  doi          = {{10.3390/met12010122}},
  volume       = {{12}},
  year         = {{2022}},
}

@article{34652,
  author       = {{Vieth, P. and Garthe, M.-A. and Voswinkel, Dietrich and Schaper, Mirko and Grundmeier, Guido}},
  issn         = {{0257-8972}},
  journal      = {{Surface and Coatings Technology}},
  keywords     = {{Materials Chemistry, Surfaces, Coatings and Films, Surfaces and Interfaces, Condensed Matter Physics, General Chemistry}},
  publisher    = {{Elsevier BV}},
  title        = {{{Enhancement of the delamination resistance of adhesive film coated surface laser melted aluminum 7075-T6 alloy by aminophosphonic acid adsorption}}},
  doi          = {{10.1016/j.surfcoat.2022.128835}},
  volume       = {{447}},
  year         = {{2022}},
}

@article{41496,
  author       = {{Hein, Maxwell and Lopes Dias, Nelson Filipe and Kokalj, David and Stangier, Dominic and Hoyer, Kay-Peter and Tillmann, Wolfgang and Schaper, Mirko}},
  issn         = {{0142-1123}},
  journal      = {{International Journal of Fatigue}},
  keywords     = {{Industrial and Manufacturing Engineering, Mechanical Engineering, Mechanics of Materials, General Materials Science, Modeling and Simulation}},
  publisher    = {{Elsevier BV}},
  title        = {{{On the influence of physical vapor deposited thin coatings on the low-cycle fatigue behavior of additively processed Ti-6Al-7Nb alloy}}},
  doi          = {{10.1016/j.ijfatigue.2022.107235}},
  volume       = {{166}},
  year         = {{2022}},
}

@article{32332,
  author       = {{Krüger, Jan Tobias and Hoyer, Kay-Peter and Hengsbach, Florian and Schaper, Mirko}},
  issn         = {{2238-7854}},
  journal      = {{Journal of Materials Research and Technology}},
  keywords     = {{Metals and Alloys, Surfaces, Coatings and Films, Biomaterials, Ceramics and Composites}},
  pages        = {{2369--2387}},
  publisher    = {{Elsevier BV}},
  title        = {{{Formation of insoluble silver-phases in an iron-manganese matrix for bioresorbable implants using varying laser beam melting strategies}}},
  doi          = {{10.1016/j.jmrt.2022.06.006}},
  volume       = {{19}},
  year         = {{2022}},
}

@article{41498,
  author       = {{Krüger, Jan Tobias and Hoyer, Kay-Peter and Hengsbach, Florian and Schaper, Mirko}},
  issn         = {{2238-7854}},
  journal      = {{Journal of Materials Research and Technology}},
  keywords     = {{Metals and Alloys, Surfaces, Coatings and Films, Biomaterials, Ceramics and Composites}},
  pages        = {{2369--2387}},
  publisher    = {{Elsevier BV}},
  title        = {{{Formation of insoluble silver-phases in an iron-manganese matrix for bioresorbable implants using varying laser beam melting strategies}}},
  doi          = {{10.1016/j.jmrt.2022.06.006}},
  volume       = {{19}},
  year         = {{2022}},
}

@article{41503,
  abstract     = {{<jats:p>The quasi in-situ indentation behaviour of &lt;110&gt;||BD and &lt;111&gt;||BD-oriented grains in a FeCo alloy is studied in this investigation. The effect of build height on melt pool shape and melt pool size is also studied by finite element method simulations. As the building height increases, the aspect ratio of the elliptical melt pool increases. Correspondingly, the effect of the laser scan speed on the melt pool shape and size is studied by the finite element method, because, as the laser scan speed increases, the aspect ratio of the elliptical melt pool increases, too. The microstructural characterisation of the indentation area before and after indentation is performed by electron backscatter diffraction (EBSD). Based on the EBSD data grain reference orientation deviation (GROD), calculations are performed to describe the effect of indentations on the neighbouring grain orientations. High GROD angles are detected in the neighbouring grain region adjoining the indented grain. An in-depth slip trace analysis shows the activation of all three slip systems ({110}&lt;111&gt;, {112}&lt;111&gt; and {123}&lt;111&gt;) which is also confirmed by slip lines on the sample surface that are detected by laser scanning confocal microscopy. A high concentration of geometrically necessary dislocations (GNDs) are observed on the adjoining area to the indentation. Local surface topography measurements by laser scanning confocal microscopy confirmed the formation of pile-ups near the indentation.</jats:p>}},
  author       = {{Pramanik, Sudipta and Tasche, Frederik and Hoyer, Kay-Peter and Schaper, Mirko}},
  issn         = {{2673-8724}},
  journal      = {{Magnetism}},
  keywords     = {{General Earth and Planetary Sciences, General Environmental Science}},
  number       = {{2}},
  pages        = {{88--104}},
  publisher    = {{MDPI AG}},
  title        = {{{Orientation-Dependent Indentation Behaviour of Additively Manufactured FeCo Sample: A Quasi In-Situ Study}}},
  doi          = {{10.3390/magnetism2020007}},
  volume       = {{2}},
  year         = {{2022}},
}

@article{41490,
  author       = {{Hein, Maxwell and Lopes Dias, Nelson Filipe and Kokalj, David and Stangier, Dominic and Hoyer, Kay-Peter and Tillmann, Wolfgang and Schaper, Mirko}},
  issn         = {{0142-1123}},
  journal      = {{International Journal of Fatigue}},
  keywords     = {{Industrial and Manufacturing Engineering, Mechanical Engineering, Mechanics of Materials, General Materials Science, Modeling and Simulation}},
  publisher    = {{Elsevier BV}},
  title        = {{{On the influence of physical vapor deposited thin coatings on the low-cycle fatigue behavior of additively processed Ti-6Al-7Nb alloy}}},
  doi          = {{10.1016/j.ijfatigue.2022.107235}},
  volume       = {{166}},
  year         = {{2022}},
}

@article{44238,
  abstract     = {{<jats:p>In numerous turbomachinery applications, e.g., in aero-engines with regenerators for improving specific fuel consumption (SFC), heat exchangers with low-pressure loss are required. Pil low-plate heat exchangers (PPHE) are a novel exchanger type and promising candidates for high-speed flow applications due to their smooth profiles avoiding blunt obstacles in the flow path. This work deals with the overall system behavior and gas dynamics of pillow-plate channels. A pillow-plate channel was placed in the test section of a blow-down wind tunnel working with dry air, and compressible flow phenomena were investigated utilizing conventional and focusing schlieren optics; furthermore, static and total pressure measurements were performed. The experiments supported the assumption that the system behavior can be described through a Fanno–Rayleigh flow model. Since only wavy walls with smooth profiles were involved, linearized gas dynamics was able to cover important flow features within the channel. The effects of the wavy wall structures on pressure drop and Mach number distribution within the flow path were investigated, and a good qualitative agreement with theoretical and numerical predictions was found. The present analysis demonstrates that pressure losses in pillow-plate heat exchangers are rather low, although their strong turbulent mixing enables high convective heat transfer coefficients.</jats:p>}},
  author       = {{Sundermeier, Stephan and Passmann, Maximilian and aus der Wiesche, Stefan and Kenig, Eugeny Y.}},
  issn         = {{2504-186X}},
  journal      = {{International Journal of Turbomachinery, Propulsion and Power}},
  keywords     = {{Mechanical Engineering, Energy Engineering and Power Technology, Aerospace Engineering}},
  number       = {{2}},
  publisher    = {{MDPI AG}},
  title        = {{{Flow in Pillow-Plate Channels for High-Speed Turbomachinery Heat Exchangers}}},
  doi          = {{10.3390/ijtpp7020012}},
  volume       = {{7}},
  year         = {{2022}},
}

@article{44236,
  author       = {{Wende, Marc and Staggenborg, Christoph and Kenig, Eugeny Y.}},
  issn         = {{0009-2509}},
  journal      = {{Chemical Engineering Science}},
  keywords     = {{Applied Mathematics, Industrial and Manufacturing Engineering, General Chemical Engineering, General Chemistry}},
  publisher    = {{Elsevier BV}},
  title        = {{{Modelling and simulation of zero-gravity distillation units with metal foams}}},
  doi          = {{10.1016/j.ces.2021.117097}},
  volume       = {{247}},
  year         = {{2022}},
}

@article{31496,
  abstract     = {{<jats:p>Carbon fiber reinforced plastics (CFRPs) gained high interest in industrial applications because of their excellent strength and low specific weight. The stacking sequence of the unidirectional plies forming a CFRP laminate, and their thicknesses, primarily determine the mechanical performance. However, during manufacturing, defects, e.g., pores and residual stresses, are induced, both affecting the mechanical properties. The objective of the present work is to accurately measure residual stresses in CFRPs as well as to investigate the effects of stacking sequence, overall laminate thickness, and the presence of pores on the residual stress state. Residual stresses were measured through the incremental hole-drilling method (HDM). Adequate procedures have been applied to evaluate the residual stresses for orthotropic materials, including calculating the calibration coefficients through finite element analysis (FEA) based on stacking sequence, laminate thickness and mechanical properties. Using optical microscopy (OM) and computed tomography (CT), profound insights into the cross-sectional and three-dimensional microstructure, e.g., location and shape of process-induced pores, were obtained. This microstructural information allowed for a comprehensive understanding of the experimentally determined strain and stress results, particularly at the transition zone between the individual plies. The effect of pores on residual stresses was investigated by considering pores to calculate the calibration coefficients at a depth of 0.06 mm to 0.12 mm in the model and utilizing these results for residual stress evaluation. A maximum difference of 46% in stress between defect-free and porous material sample conditions was observed at a hole depth of 0.65 mm. The significance of employing correctly calculated coefficients for the residual stress evaluation is highlighted by mechanical validation tests.</jats:p>}},
  author       = {{Wu, Tao and Kruse, Roland and Tinkloh, Steffen Rainer and Tröster, Thomas and Zinn, Wolfgang and Lauhoff, Christian and Niendorf, Thomas}},
  issn         = {{2504-477X}},
  journal      = {{Journal of Composites Science}},
  keywords     = {{Engineering (miscellaneous), Ceramics and Composites}},
  number       = {{5}},
  publisher    = {{MDPI AG}},
  title        = {{{Experimental Analysis of Residual Stresses in CFRPs through Hole-Drilling Method: The Role of Stacking Sequence, Thickness, and Defects}}},
  doi          = {{10.3390/jcs6050138}},
  volume       = {{6}},
  year         = {{2022}},
}

@article{32814,
  author       = {{Wu, T. and Degener, S. and Tinkloh, Steffen Rainer and Liehr, A. and Zinn, W. and Nobre, J.P. and Tröster, Thomas and Niendorf, T.}},
  issn         = {{0263-8223}},
  journal      = {{Composite Structures}},
  keywords     = {{Civil and Structural Engineering, Ceramics and Composites}},
  publisher    = {{Elsevier BV}},
  title        = {{{Characterization of residual stresses in fiber metal laminate interfaces - A combined approach applying hole-drilling method and energy-dispersive X-ray diffraction}}},
  doi          = {{10.1016/j.compstruct.2022.116071}},
  year         = {{2022}},
}

@article{29951,
  abstract     = {{The components of a body in white consist of many individual thin-walled sheet metal parts, which usually are manufactured in deep-drawing processes. In general, the conditions in a deep-drawing process change due to changing tribology conditions, varying degrees of spring back, or scattering material properties in the sheet blanks, which affects the resulting pre-strain. Mechanical joining processes, especially clinching, are influenced by these process-related pre-strains. The final geometric shape of a clinched joint is affected to a significant level by the prior material deformation when joining with constant process parameters. That leads to a change in the stiffness and force transmission in the clinched joint due to the different geometric dimensions, such as interlock, neck thickness and bottom thickness, which directly affect the load bearing capacity. Here, the influence of the pre-straining in the deep drawing process on the force distribution in clinch points in an automotive assembly is investigated by finite-element models numerically. In further studies, the results are implemented in an optimization tool for designing clinched components. The methodology starts with a pre-straining of metal sheets. This step is followed by 2D rotationally symmetric forming simulations of the joining process. The resulting mesh of each forming simulation is rotated and 3D models are obtained. The clinched joint solid model with pre-strains is used further to determine the joint stiffnesses. With the simulation of the same test set-up with an equivalent point-connector model, the equivalent stiffness for each pre-strain combination is determined. Simulations are performed on a clinched component to assess the influence of pre-strain and sheet thinning on the clinched joint loadings by using the equivalent stiffnesses. The investigations clearly show that for the selected component, the loadings at the clinch points are dependent on the sheet thinning and the stiffnesses due to pre-strain. The magnitude of the influence varies depending on the quantity considered. For example, the shear force is more sensitive to the joint stiffness than to the sheet thinning.</jats:p>}},
  author       = {{Martin, Sven and Bielak, Christian Roman and Bobbert, Mathias and Tröster, Thomas and Meschut, Gerson}},
  issn         = {{0944-6524}},
  journal      = {{Production Engineering}},
  keywords     = {{Industrial and Manufacturing Engineering, Mechanical Engineering}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Numerical investigation of the clinched joint loadings considering the initial pre-strain in the joining area}}},
  doi          = {{10.1007/s11740-021-01103-w}},
  year         = {{2022}},
}

@article{30591,
  author       = {{Bertling, René and Hack, M. and Ausner, I. and Horschitz, B. and Bernemann, Sören Antonius and Kenig, Eugeny}},
  issn         = {{0009-2509}},
  journal      = {{Chemical Engineering Science}},
  keywords     = {{Applied Mathematics, Industrial and Manufacturing Engineering, General Chemical Engineering, General Chemistry}},
  publisher    = {{Elsevier BV}},
  title        = {{{Modelling film and rivulet flows on microstructured surfaces using CFD methods}}},
  doi          = {{10.1016/j.ces.2021.117414}},
  volume       = {{251}},
  year         = {{2022}},
}

@article{30382,
  author       = {{Bertling, R. and Hack, M. and Ausner, I. and Horschitz, B. and Bernemann, S. and Kenig, E.Y.}},
  issn         = {{0009-2509}},
  journal      = {{Chemical Engineering Science}},
  keywords     = {{Applied Mathematics, Industrial and Manufacturing Engineering, General Chemical Engineering, General Chemistry}},
  publisher    = {{Elsevier BV}},
  title        = {{{Modelling film and rivulet flows on microstructured surfaces using CFD methods}}},
  doi          = {{10.1016/j.ces.2021.117414}},
  volume       = {{251}},
  year         = {{2022}},
}

@article{34000,
  abstract     = {{<jats:title>Abstract</jats:title>
               <jats:p>This paper presents the characterization of the microstructure evolution during flow forming of austenitic stainless steel AISI 304L. Due to plastic deformation of metastable austenitic steel, phase transformation from γ-austenite into α’-martensite occurs. This is initiated by the formation of shear bands as product of the external stresses. By means of coupled microscopic and micromagnetic investigations, a characterization of the microstructure was carried out. In particular, this study shows the distribution of the strain-induced α’-martensite and its influence on material properties like hardness at different depths. The microstructural analyses by means of electron backscattered diffraction (EBSD) technique, evidence a higher amount of α’-martensite (ca. 23 %) close to the outer specimen surface, where the plastic deformation and the direct contact with the forming tool take place. In the middle area (ca. 1.5 mm depth from the outer surface), the portion of transformed α’-martensite drops to 7 % and in the inner surface to 2 %. These results are well correlated with microhardness and micromagnetic measurements at different depths. EBSD and atomic force microscopy (AFM) were used to make a detailed characterization of the topography and degree of deformation of the shear bands. Likewise, the mechanisms of nucleation of α’-martensite were discussed. This research contributes to the development of micromagnetic sensors to monitor the evolution of properties during flow forming. This makes them more suitable for closed-loop property control, which offers possibilities for an application-oriented and more efficient production.</jats:p>}},
  author       = {{Rozo Vasquez, Julian and Kanagarajah, Hanigah and Arian, Bahman and Kersting, Lukas and Homberg, Werner and Trächtler, Ansgar and Walther, Frank}},
  issn         = {{2195-8599}},
  journal      = {{Practical Metallography}},
  keywords     = {{Metals and Alloys, Mechanics of Materials, Condensed Matter Physics, Electronic, Optical and Magnetic Materials}},
  number       = {{11}},
  pages        = {{660--675}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Coupled microscopic and micromagnetic depth-specific analysis of plastic deformation and phase transformation of metastable austenitic steel AISI 304L by flow forming}}},
  doi          = {{10.1515/pm-2022-0064}},
  volume       = {{59}},
  year         = {{2022}},
}

@article{30213,
  abstract     = {{<jats:p>Requirement changes and cascading effects of change propagation are major sources of inefficiencies in product development and increase the risk of project failure. Proactive change management of requirement changes yields the potential to handle such changes efficiently. A systematic approach is required for proactive change management to assess and reduce the risk of a requirement change with appropriate effort in industrial application. Within the paper at hand, a novel method for Proactive Management of Requirement Changes (ProMaRC) is presented. It is developed in close collaboration with industry experts and evaluated based on workshops, pilot users’ feedback, three industrial case studies from the automotive industry and five development projects from research. To limit the application effort, an automated approach for dependency analysis based on the machine learning technique BERT and semi-automated assessment of change likelihood and impact using a modified PageRank algorithm is developed. Applying the method, the risks of requirement changes are assessed systematically and reduced by means of proactive change measures. Evaluation shows high performance of dependency analysis and confirms the applicability and usefulness of the method. This contribution opens up the research space of proactive risk management for requirement changes which is currently almost unexploited. It enables more efficient product development.</jats:p>}},
  author       = {{Gräßler, Iris and Oleff, Christian and Preuß, Daniel}},
  issn         = {{2076-3417}},
  journal      = {{Applied Sciences}},
  keywords     = {{Fluid Flow and Transfer Processes, Computer Science Applications, Process Chemistry and Technology, General Engineering, Instrumentation, General Materials Science}},
  number       = {{4}},
  publisher    = {{MDPI AG}},
  title        = {{{Proactive Management of Requirement Changes in the Development of Complex Technical Systems}}},
  doi          = {{10.3390/app12041874}},
  volume       = {{12}},
  year         = {{2022}},
}

@article{44469,
  author       = {{Menge, Dennis and Schmid, Hans-Joachim}},
  issn         = {{1022-1360}},
  journal      = {{Macromolecular Symposia}},
  keywords     = {{Materials Chemistry, Polymers and Plastics, Organic Chemistry, Condensed Matter Physics}},
  number       = {{1}},
  publisher    = {{Wiley}},
  title        = {{{Low Temperature Laser Sintering with PA12 and PA6 on a Standard System}}},
  doi          = {{10.1002/masy.202100397}},
  volume       = {{404}},
  year         = {{2022}},
}

@article{42951,
  abstract     = {{<jats:sec><jats:title content-type="abstract-subheading">Purpose</jats:title><jats:p>Information and communication technologies (ICT) has an increasing impact on schools. School leaders play a key role in this context as drivers of innovation including those related to ICT. Against this background, the study presented in this article focuses on school leadership and management activities with ICT and related challenges. It sought to analyze how frequently German school principals use ICT compared to principals in other countries, what distinct clusters of German principals could be identified in terms of ICT usage and how principals viewed ICT in schools and related challenges.</jats:p></jats:sec><jats:sec><jats:title content-type="abstract-subheading">Design/methodology/approach</jats:title><jats:p>A mixed-methods approach was chosen, using quantitative data from both the international comparative large-scale assessment study ICILS 2018 and the explorative qualitative data from Germany. For the international comparison, the school principal data sets of the 12 international participants of the <jats:italic>International Computer and Information Literacy Study</jats:italic> (ICILS) 2018 were taken into account: Chile, Denmark, Finland, France, Germany, Italy, Kazakhstan, Republic of Korea, Luxembourg, Portugal, Uruguay and the United States. To look beyond averaged frequencies, a latent class analysis (LCA) was conducted to identify possible clusters of school leaders with distinct usage patterns of ICT for leadership and management activities.</jats:p></jats:sec><jats:sec><jats:title content-type="abstract-subheading">Findings</jats:title><jats:p>The results indicate that, in general, German principals use ICT for leadership and management activities on a similar level as their international colleagues. However, they seem to communicate with education authorities significantly more often than their international colleagues, whereas representative activities (presentations, home page) are rather infrequent. The qualitative data point to significant barriers to fully harnessing the potential of using ICT for leadership, management and school improvement such as lack of competencies and lack of adequate support.</jats:p></jats:sec><jats:sec><jats:title content-type="abstract-subheading">Originality/value</jats:title><jats:p>To the best of the authors’ knowledge, this is the first study that focuses on school leadership and management activities using ICT with such a data set. The results provide insights into how German principals use ICT to lead and manage their schools compared to their international counterparts. The qualitative data offers additional insights into possible reasons hindering a more effective use of ICT.</jats:p></jats:sec>}},
  author       = {{Tulowitzki, Pierre and Gerick, Julia and Eickelmann, Birgit}},
  issn         = {{0951-354X}},
  journal      = {{International Journal of Educational Management}},
  keywords     = {{Organizational Behavior and Human Resource Management, Education, Organizational Behavior and Human Resource Management, Education}},
  number       = {{2}},
  pages        = {{133--151}},
  publisher    = {{Emerald}},
  title        = {{{The role of ICT for school leadership and management activities: an international comparison}}},
  doi          = {{10.1108/ijem-06-2021-0251}},
  volume       = {{36}},
  year         = {{2022}},
}

@article{33741,
  abstract     = {{There are many concepts of signed graph coloring which are defined by assigning colors to the vertices of the graphs. These concepts usually differ in the number of self-inverse colors used. We introduce a unifying concept for this kind of coloring by assigning elements from symmetric sets to the vertices of the signed graphs. In the first part of the paper, we study colorings with elements from symmetric sets where the number of self-inverse elements is fixed. We prove a Brooks’-type theorem and upper bounds for the corresponding chromatic numbers in terms of the chromatic number of the underlying graph. These results are used in the second part where we introduce the symset-chromatic number χsym(G,σ) of a signed graph (G,σ). We show that the symset-chromatic number gives the minimum partition of a signed graph into independent sets and non-bipartite antibalanced subgraphs. In particular, χsym(G,σ)≤χ(G). In the final section we show that these colorings can also be formalized as DP-colorings.}},
  author       = {{Cappello, Chiara and Steffen, Eckhard}},
  issn         = {{0218-0006}},
  journal      = {{Annals of Combinatorics}},
  keywords     = {{Discrete Mathematics and Combinatorics}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Symmetric Set Coloring of Signed Graphs}}},
  doi          = {{10.1007/s00026-022-00593-4}},
  year         = {{2022}},
}