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INTRODUCING HYBRID LEARNING TO LEARNING FACTORIES
No full textThe ongoing digital transformation of the manufacturing industry needs to be met with new formsof education and training to maintain a highly skilled workforce. New professional education concepts needto provide effective learning content that is industry-relevant, of high quality, and easily accessible. To tacklethese challenges, the paper presents a methodology for developing a course founded on a combination ofdidactic approaches including blended and hybrid learning, active learning, and flipped classroom.According to industry needs in South-East Europe, the course design is then applied to selected topics arounda smart assembly workstation, i.e., human-robot collaboration, enhanced quality control, and leanmanufacturing 4.0. The trainings will be offered online, via E-learning and through the partners’ LearningFactories, i.e., hands-on. Examples of different concepts are presented in each Learning Factory
Deconstructing the urban viewpoint: Exploring uneven regional development with Nancy Fraser’s notion of justice
No full textUneven regional development fomented by city-centric growth agendas generates significant challenges for regional peripheries. Placing regional margins and other plural geographies at the center, in this article we apply a normative framework based on justice theory to uncover the dominance of urban viewpoints in urban regional development policy. Departing from Nancy Fraser’s three-dimensional justice theory, we provide a deconstruction of city-centrism by illustrating how regional disparities in two regions in Sweden are not only reproduced by economic maldistribution but also by political misrepresentation and cultural misrecognition. By doing so, we illustrate the fruitfulness of applying a normative justice framework to create a broader understanding of factors that contribute to the political production of uneven regional development and need to be addressed if a transformative and progressive change is to occur
Electro-assisted filtration of microfibrillated cellulose: the impact of the degree of fibrillation
Get PDFEfficient dewatering is necessary to achieve an economically sustainable large-scale production of microfibrillated cellulose (MFC) because the low solids content of the final product (< 3 wt.%) results in high costs related to transportation and storage, and problems for products with water incompatibility. Mechanical dewatering is preferred to thermal drying due to its lower energy demand, but MFC has a very high filtration resistance, which implies that an excessive filter area is necessary. Thus, to improve the dewatering, electro-assisted filtration may be used. In this study a bench-scale dead-end filter press was modified and the electro-assisted filtration of MFC, with two degrees of fibrillation, was investigated. The impact of the degree of fibrillation was clear when either pressure or electric field were applied separately. It was more challenging to dewater MFC with a higher degree of fibrillation using conventional filtration due to a greater surface area being subjected to the liquid flow. The opposite was found when using an electric field alone: the more fibrillated material has a higher surface charge and thereby is impacted more by the electric field. A combination of pressure and electric field resulted in a greatly improved dewatering rate, but no significant difference could be observed between the two qualities. After dewatering, the water retention value was slightly decreased, but the material still showed a gel-like behaviour, although the network strength was slightly reduced, as seen by a reduction in yield stress, storage and loss moduli. This was plausibly due to a decrease in the surface area and/or deformed network
Proton halo effects in the 8B+64Zn collision around the Coulomb barrier
Get PDFThe 8B+64Zn reaction at 38.5 MeV has been studied at HIE-ISOLDE CERN to investigate proton halo effect on the reaction dynamics. For the first time it was used the only existing post-accelerated 8B beam. The measured elastic scattering angular distribution showed a small suppression of the Coulomb-nuclear interference peak, opposite to what observed for the one-neutron halo nucleus 11Be on the same target where a large suppression was observed instead. Inclusive angular and energy distributions of breakup fragments were also measured showing that, both, elastic and non-elastic breakup contribute. The presence of the additional Coulomb interactions halo-core and halo-target in 8B makes the reaction dynamics in this proton-halo nucleus different than the neutron-halo case
The silent tribe: Mapping the variety of researchers’ science communication practices across STEM disciplines
Get PDFScientists’ communication with the public has increased in recent years,responding to digitalization and the push to democratise access to knowledge.Research has shown that academics produce a variety of genres beyond academia,spanning diverse purposes and languages. However, what kind of writingpractices occur within science communication, and to what extent scientistsengage in it, still needs further investigation. In order to further the understandingof current writing practices in academia, we explore scientists’ communication ofscience at a Swedish university of technology. We analyse publications for nonacademicaudiences in the university’s publication repository combining contentanalysis, genre analysis, and co-authorship network analysis. By merging thesemethods, we reveal a complex picture of purposes, audiences, genres, andcollaborations. We found that field of study and topic catalyse sciencecommunication writing: the majority of the publications relate to either climatechange or architecture and civil engineering, and stem from a small number ofactive, senior scientists at two departments. We discuss potential reasons forthese patterns, including seniority, processes for promotion and tenure, sciencecommunication’s role in academic work-life, and finally differences indepartmental and disciplinary culture and conditions
RIMBO - An Ontology for\ua0Model Revision Databases
No full textThe use of computational models is growing throughout most scientific domains. The increased complexity of such models, as well as the increased automation of scientific research, imply that model revisions need to be systematically recorded. We present RIMBO (Revisions for Improvements of Models in Biology Ontology), which describes the changes made to computational biology models. The ontology is intended as the foundation of a database containing and describing iterative improvements to models. By recording high level information, such as modelled phenomena, and model type, using controlled vocabularies from widely used ontologies, the same database can be used for different model types. The database aims to describe the evolution of models by recording chains of changes to them. To make this evolution transparent, emphasise has been put on recording the reasons, and descriptions, of the changes. We demonstrate the usefulness of a database based on this ontology by modelling the update from version 8.4.1 to 8.4.2 of the genome-scale metabolic model Yeast8, a modification proposed by an abduction algorithm, as well as thousands of simulated revisions. This results in a database demonstrating that revisions can successfully be modelled in a semantically meaningful and storage efficient way. We believe such a database is necessary for performing automated model improvement at scale in systems biology, as well as being a useful tool to increase the openness and traceability for model development. With minor modifications the ontology can also be used in other scientific domains. The ontology is made available at https://github.com/filipkro/rimbo and will be continually updated
Exploring the High-Temperature Window of Operation for Organic Photovoltaics: A Combined Experimental and Simulations Study
Get PDFThe global climate change negatively affects the photovoltaic performance of traditional solar cell technologies. This article investigates the potential of organic photovoltaics (OPV) for high-temperature environments, ranging from urban hot summers (30—40\ua0\ub0C) and desert regions (65\ua0\ub0C) up to (aero) space conditions (130\ua0\ub0C), the thermal window in which OPV can operate. The approach is based on a combination of experiments and simulations up to 180\ua0\ub0C, moving significantly beyond the conventional temperature ranges reported in the literature. New 2H-benzo[d][1,2,3]triazole-5,6-dicarboxylic imide-based copolymers with decomposition onset temperatures above 340\ua0\ub0C are used for this study, in combination with non-fullerene acceptors. Contrary to their inorganic counterparts, OPV devices show a positive temperature coefficient up to ≈90\ua0\ub0C. At temperatures of 150\ua0\ub0C, they are still operational, retaining their room temperature efficiency. Complementary simulations are performed using an in-house developed software package that numerically solves the drift-diffusion equations to understand the general trends in the obtained current–voltage characteristics and the materials’ intrinsic behavior as a function of temperature. The presented methodology of combined high-temperature experiments and simulations can be further applied to investigate the thermal window of operation for other OPV material systems, opening novel high-temperature application routes
Functionality, Losses, and Lifetime Comparison of Hydropower Generator Excitation System Converters
No full textThis paper examines different types of converters used in an excitation system of a hydropower generator. The investigation focuses on the functionality, losses, and lifetime considerations. Although both the two-level converter and the three-level neutral point clamped converter can deliver a consistent DC voltage to the field winding of the excitation system, the converter using Silicon Carbide MOSFET power switches has advantages, it demonstrates superior performance in terms of losses and lifetime. On the other hand, the three-level NPC converter proves to be a viable choice in scenarios where field current distortion or high voltage level requirements are present
Revealing the Free Energy Landscape of Halide Perovskites: Metastability and Transition Characters in CsPbBr3 and MAPbI3
Get PDFHalide perovskites have emerged as a promising class of materials for photovoltaic applications. A challenge of these applications is preventing the crystal structure from degrading to photovoltaically inactive phases, which requires an understanding of the free energy landscape of these materials. Here, we uncover the free energy landscape of two prototypical halide perovskites, CsPbBr3 and MAPbI3, via atomic-scale simulations using umbrella sampling and machine-learned potentials. For CsPbBr3, we find very small free energy differences and barriers close to the transition temperatures for both the tetragonal-to-cubic and orthorhombic-to-tetragonal transitions. For MAPbI3, however, the situation is more intricate. In particular, the orthorhombic-to-tetragonal transition exhibits a large free energy barrier, and there are several competing tetragonal phases. Using large-scale molecular dynamics simulations, we explore the character of these transitions and observe the latent heat and a discrete change in the structural parameters for the tetragonal-to-cubic phase transitions in both CsPbBr3 and MAPbI3, indicating first-order transitions. We find that in MAPbI3, the orthorhombic phase has an extended metastability range, and we identify a second metastable tetragonal phase. Finally, we compile a phase diagram for MAPbI3 that includes potential metastable phases
Facile synthesis of nitrogen, sulfur co-doped carbon quantum dots for selective detection of mercury (II)
No full textDeveloping carbon quantum dots with high throughput and quantum yields is important to boost their application in environmental detection. This study proposes nitrogen, sulfur co-doped carbon quantum dots as a fluorescent probe for mercury detection in an aqueous environment, which was synthesized by a facile and high-output tactic using methyl orange as a precursor for the first time. Results demonstrate that the obtained carbon quantum dots have a high selectivity, low detection limit of 237\ua0nM, and fast response time, approximately 30\ua0s, for trace mercury. The detection mechanism involves the synergistic action of static quenching, inner filter effect, and photo-induced electron transfer. Moreover, results show a high product yield (75.6%) and quantum yield (29.4%), which are higher compared to previous studies. These findings indicate that developed carbon quantum dots are promising sensing nanomaterials for mercury detection