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See detailA short Survey on the Cyber Security in Control Systems
Bezzaoucha, Souad UL; Voos, Holger UL

Scientific Conference (2020, July)

In the present survey paper, we give a short, yet exhaustive state-of-the-art about the cyber-security applied to control systems, especially the event-based strategy. Indeed, in the past few years, due ... [more ▼]

In the present survey paper, we give a short, yet exhaustive state-of-the-art about the cyber-security applied to control systems, especially the event-based strategy. Indeed, in the past few years, due to a highest degree of connectivity in modern systems, new related control-specific cyber-physical systems security challengesarise and novel approaches integrating the cyber aspect are developed.Our goal in this paper is then to provide an overview of attack-modeling and security analysis approaches in recent works thatexplore networked control systems subject to cyber-attacks attacks. To this end, we look at the control, estimation, and modeling problems. [less ▲]

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See detailPractical Posterior Error Bounds from Variational Objectives
Huggins, Jonathan; Kasprzak, Mikolaj UL; Campbell, Trevor et al

in Proceedings of the 23rd International Conference on Artificial Intelligence and Statistics (AISTATS) (2020, June)

Detailed reference viewed: 6 (2 UL)
See detailConstcamer Paintings as Epistemic Images: Early Modern Theaters of Wisdom
Koeleman, Floor UL

Scientific Conference (2020, April)

This paper argues, against existing literature, that 17th-cent. constcamer paintings were objects to think with, functioning as the two-dimensional space of artificial memory. In turn, these artworks ... [more ▼]

This paper argues, against existing literature, that 17th-cent. constcamer paintings were objects to think with, functioning as the two-dimensional space of artificial memory. In turn, these artworks complicate conventional definitions of epistemic images more broadly. I focus on an analysis of constcamer paintings accounting for the reception of the ancients and the mnemonic and propaedeutic role of images, entailing concepts such as wonder or thauma (from Greek θεάομαι), the drive to gather knowledge, memory as the locus of this ‘collection’, and recollecting as the intellectual process of interaction with memorized knowledge. The term inventor, referring to the creator of a given collection, is derived from the rhetorical technique for the retrieval of information. The theatre or ‘place for viewing’ provided the physical context for the collected wisdom. Inventors of constcamer paintings – often artists themselves – vitally participated in knowledge formation contributing to contemporary intellectual debates. [less ▲]

Detailed reference viewed: 95 (2 UL)
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See detailTheoretical approaches towards multilingual education
Kirsch, Claudine UL; Duarte

in Kirsch, Claudine; Duarte, Joana (Eds.) Multilingual approaches for teaching and learning. From acknowledging to capitalising on multilingualism in European mainstream education (2020)

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See detailTranslanguaging practices in early childhood education in Luxembourg
Kirsch, Claudine UL

in Kirsch, Claudine; Duarte, Joana (Eds.) Multilingual approaches for teaching and learning. From acknowledging to capitalizing on multilingualism in European mainstream education. (2020)

Calls for multilingual pedagogies have reached early childhood education and some programmes have been implemented in Europe. However, their focus frequently remains on the majority language and home ... [more ▼]

Calls for multilingual pedagogies have reached early childhood education and some programmes have been implemented in Europe. However, their focus frequently remains on the majority language and home languages are given little space. For multilingual programmes to be inclusive and empowering, professionals need to break with monolingual practices based on monolingual ideologies. The resource-oriented pedagogy of translanguaging which challenges hegemonic practices, is one way in which professionals can give space to all languages, leverage children’s resources and contribute to their development. The present chapter presents the findings of a professional development on multilingual pedagogies in Luxembourg. Data stem from observations, video-recorded activities and interviews with four practitioners, two working in a formal education setting and two in a non-formal one. The findings show that the practitioners developed a positive stance towards translanguaging and multilingual education, learned to design a child-centred and holistic multilingual learning environment and used languages flexibly, deploying translation, code-switching and translanguaging. This dynamic language use facilitated communication, participation, language learning and well-being. There were differences between the practitioners’ flexible language use. The professionals in the school did not use pair talk, made less use of code-switching and used languages more strategically and responsibly than the caregivers in the crèche. [less ▲]

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See detailEffective professional development and sustainability of multilingual approaches
Kirsch, Claudine UL; Duarte, Joana; Palviainen, Åsa

in Kirsch, Claudine; Duarte, Joana (Eds.) Multilingual approaches for teaching and learning_From acknowledging to capitalising on multilingualism in European mainstream education (2020)

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See detailA DEM modeling of biomass fast pyrolysis in a double auger reactor
Qi, Fenglei UL; Wright, Mark

in International Journal of Heat and Mass Transfer (2020), 150

Thermochemical conversion of biomass via fast pyrolysis is a proven pathway to product low-carbon crude bio-oils. In this research, an extended discrete element method (DEM) is proposed for simulating ... [more ▼]

Thermochemical conversion of biomass via fast pyrolysis is a proven pathway to product low-carbon crude bio-oils. In this research, an extended discrete element method (DEM) is proposed for simulating biomass fast pyrolysis reacting granular flows in a double auger reactor, in which particle hydrodynamics and interparticle heat transfer processes are involved and coupled with chemical reactions in solid particles. An adaptive time step algorithm is proposed to achieve a stable coupling between the integration of reaction ordinary differential equations and the DEM solver, and the algorithm is proven computationally efficient. A multi-component fast pyrolysis kinetics is adopted and its modeling accuracy is assessed by carrying out simulations of benchmark biomass pyrolysis experiments and comparing the prediction results with experimental data. The predicted product yields of bio-oil, char and non-condensable gas from the simulation of the biomass fast pyrolysis in the auger reactor are in satisfactory agreement with experimental measurements. The decomposition rates of biomass components in the reactor are revealed from the simulation and the pyrolysis number Py is calculated from the decomposition rate of biomass and the heat transfer coefficient. The Py number illustrates that the biomass fast pyrolysis process is limited by the heat transfer process at particle size of 2 mm. [less ▲]

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See detailMetamorphic Security Testing for Web Systems
Mai, Xuan Phu UL; Pastore, Fabrizio UL; Goknil, Arda et al

in IEEE International Conference on Software Testing, Verification and Validation (ICST) 2020 (2020, March)

Security testing verifies that the data and the resources of software systems are protected from attackers. Unfortunately, it suffers from the oracle problem, which refers to the challenge, given an input ... [more ▼]

Security testing verifies that the data and the resources of software systems are protected from attackers. Unfortunately, it suffers from the oracle problem, which refers to the challenge, given an input for a system, of distinguishing correct from incorrect behavior. In many situations where potential vulnerabilities are tested, a test oracle may not exist, or it might be impractical due to the many inputs for which specific oracles have to be defined. In this paper, we propose a metamorphic testing approach that alleviates the oracle problem in security testing. It enables engineers to specify metamorphic relations (MRs) that capture security properties of the system. Such MRs are then used to automate testing and detect vulnerabilities. We provide a catalog of 22 system-agnostic MRs to automate security testing in Web systems. Our approach targets 39% of the OWASP security testing activities not automated by state-of-the-art techniques. It automatically detected 10 out of 12 vulnerabilities affecting two widely used systems, one commercial and the other open source (Jenkins). [less ▲]

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See detailHeranführung an die mehrsprachige Pädagogik durch Filmaufnahmen in der Lehrerausbildung in Luxemburg
Kirsch, Claudine UL

in Zeitschrift für Interkulturellen Fremdsprachenunterricht (2020), 25(1), 22

Aufgrund von gesellschaftlichen, sprach- und bildungspolitischen Entwicklungen soll mehrsprachige Bildung ein fester Bestandteil des Schul- und Vorschulunterrichts sein. Es gilt deshalb, angehende ... [more ▼]

Aufgrund von gesellschaftlichen, sprach- und bildungspolitischen Entwicklungen soll mehrsprachige Bildung ein fester Bestandteil des Schul- und Vorschulunterrichts sein. Es gilt deshalb, angehende LehrerInnen auf diese Neuerung vorzubereiten und ihnen beim Aneignen von Wissen und bei der Reflexion ihrer Haltungen zu helfen. Zu diesem Zweck wurden Filmaufnahmen aus einer empirischen Forschung zur frühen mehrsprachigen Bildung in der Lehrerausbildung in Luxemburg eingesetzt. Ein Fragebogen und Gruppeninterviews mit den Studierenden zeigen, dass sie durch das Filmmaterial neues Wissen erwarben und an ihren Einstellungen arbeiteten. Die Veranschaulichung in den Filmen, die theoriegeleiteten Diskussionen im Seminar und die tiefe Auseinandersetzung und Reflexion der Studierenden waren lernförderlich. Societal developments, language policies and new understandings of language learning call for multilingual education in schools. Prospective teachers need to be prepared for this change and develop a stance and knowledge that further multilingualism. To promote learning, videos of a research project on multilingual pedagogies in early years were used in teacher education in Luxembourg. A questionnaire and group interviews with students showed that they developed new knowledge and worked on their stance towards multilingual education. The illustrations in the videos, the theory-led discussions as well as the students’ deep engagement and reflection promoted learning. [less ▲]

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See detailIdentifying Unintended Harms of Cybersecurity Measures
Chua, Yi Ting; Parkin, Simon; Edwards, Matthew et al

in Proceedings of ECRIME 2019 (2020, February 01)

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See detailPreventing Overloading Incidents on Smart Grids: A Multiobjective Combinatorial Optimization Approach
Antoniadis, Nikolaos UL; Cordy, Maxime UL; Sifaleras, Angelo et al

Scientific Conference (2020, February)

Cable overloading is one of the most critical disturbances that may occur in smart grids, as it can cause damage to the distribution power lines. Therefore, the circuits are protected by fuses so that ... [more ▼]

Cable overloading is one of the most critical disturbances that may occur in smart grids, as it can cause damage to the distribution power lines. Therefore, the circuits are protected by fuses so that, the overload could trip the fuse, opening the circuit, and stopping the flow and heating. However, sustained overloads, even if they are below the safety limits, could also damage the wires. To prevent overload, smart grid operators can switch the fuses on or off to protect the circuits, or remotely curtail the over-producing/over-consuming users. Nevertheless, making the most appropriate decision is a daunting decision-making task, notably due to contractual and technical obligations. In this paper, we define and formulate the overloading prevention problem as a Multiobjective Mixed Integer Quadratically Constrained Program. We also suggest a solution method using a combinatorial optimization approach with a state-of-the-art exact solver. We evaluate this approach for this real-world problem together with Creos Luxembourg S.A., the leading grid operator in Luxembourg, and show that our method can suggest optimal countermeasures to operators facing potential overloading incidents. [less ▲]

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See detailStereotypen hinsichtlich Schülern mit sonderpädagogischem Förderbedarf: Lehrerüberzeugen, -erwartungen und –gefühle
Pit-Ten Cate, Ineke UL; Krischler, Mireille UL

in Glock, Sabine; Kleen, Hannah (Eds.) Stereotype in der Schule (2020)

Dieses Kapitel geht der Frage nach, ob Lehrer*innenüberzeugungen und -erwartungen je nach sonderpädagogischem Förderbedarf variieren. Außerdem wurde deren Einfluss sowohl auf die Gefühle bei ... [more ▼]

Dieses Kapitel geht der Frage nach, ob Lehrer*innenüberzeugungen und -erwartungen je nach sonderpädagogischem Förderbedarf variieren. Außerdem wurde deren Einfluss sowohl auf die Gefühle bei Auseinandersetzung mit der Inklusion von unterschiedlichen Schüler*innen als auch auf die persönliche Bereitschaft, Inklusion umzusetzen, untersucht. Die Studien basieren einerseits auf dem Kontinuum-Modell der Eindrucksbildung und betrachten andererseits das Stereotype-Content-Modell, nach dem Wärme und Kompetenz über 80 % der Unterschiedlichkeit in der Personenwahrnehmung erklären. Die Ergebnisse zeigten, dass Überzeugungen und Erwartungen von der Art des Förderbedarfs beeinflusst werden. Positivere Überzeugungen bezüglich der Schüler*innenmerkmale (Wärme und Kompetenz) und höhere Leistungserwartungen waren hierbei mit positiveren Gefühlen und einer stärker ausgeprägten persönlichen Bereitschaft, die Schüler*innen mit sonderpädagogischem Förderbedarf zu inkludieren, verbunden. Abschließend werden die daraus resultierenden Konsequenzen für die Lehreraus- und weiterbildung abgeleitet und diskutiert. [less ▲]

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See detailAkademische Profile von Schüler*innen zur Bestimmung der Akkuratheit von Schulübergangsempfehlungen – eine Validierungsstudie
Pit-Ten Cate, Ineke UL; Hörstermann, Thomas UL

in Glock, Sabine; Kleen, Hannah (Eds.) Stereotype in der Schule (2020)

In verschiedenen europäischen Ländern führt der Wechsel zur Sekundarschule zu einer bedeutsamen Aufgliederung der Bildungswege, welche ein unterschiedlich hohes Schulleistungsniveau der Schüler*innen ... [more ▼]

In verschiedenen europäischen Ländern führt der Wechsel zur Sekundarschule zu einer bedeutsamen Aufgliederung der Bildungswege, welche ein unterschiedlich hohes Schulleistungsniveau der Schüler*innen voraussetzen. Die Akkuratheit der Zuweisung von Sekundarschulformen bestimmt nicht nur die Optionen der Schüler*innen bei späteren Übergangen im Bildungssystem, sondern beeinflusst auch den weiteren beruflichen und persönlichen Werdegang der Schüler*innen. Schüler*innen mit Migrationshintergrund sind auf die höheren sekundären Schulformen unterrepräsentiert. Inwiefern diese Unterrepräsentation auf stereotypgeprägte Leistungserwartungen zurückzuführen ist, ist bis jetzt unklar, denn es lisgt kein Kriterium vor, um die Urteilsakkuratheit adäquat zu messen. In diesem Kapitel wird ein Ansatz beschrieben, ein solches Akkuratheitskriterium zu entwickeln und zu validieren. In einem zweiten Schritt wird das Kriterium angewendet, um den Zusammenhang zwischen stereotypgeprägten Erwartungen und der Akkuratheit der Übergangsentscheidungen zu untersuchen. Das Kriterium erweist sich als valides Maß und könnte so einen wertvollen Ansatz für weitere Untersuchungen der Akkuratheit von Lehrerurteilen darstellen. Obwohl Lehrer*innen im Allgemeinen eine hohe Urteilsakkuratheit aufweisen, bestätigen die Befunde dennoch die Zusammenhänge zwischen stereotypgeprägten Erwartungen und Urteilsverzerrungen. [less ▲]

Detailed reference viewed: 30 (1 UL)