AI-based Question Answering Assistance for Analyzing Natural-language Requirements

in In Proceedings of the 45th International Conference on Software Engineering (ICSE'23), Melbourne 14-20 May 2023 (in press)

Abstract—By virtue of being prevalently written in natural language (NL), requirements are prone to various defects, e.g., inconsistency and incompleteness. As such, requirements are frequently subject to ... [more ▼]

Abstract—By virtue of being prevalently written in natural language (NL), requirements are prone to various defects, e.g., inconsistency and incompleteness. As such, requirements are frequently subject to quality assurance processes. These processes, when carried out entirely manually, are tedious and may further overlook important quality issues due to time and budget pressures. In this paper, we propose QAssist – a question-answering (QA) approach that provides automated assistance to stakeholders, including requirements engineers, during the analysis of NL requirements. Posing a question and getting an instant answer is beneficial in various quality-assurance scenarios, e.g., incompleteness detection. Answering requirements-related questions automatically is challenging since the scope of the search for answers can go beyond the given requirements specification. To that end, QAssist provides support for mining external domain-knowledge resources. Our work is one of the first initiatives to bring together QA and external domain knowledge for addressing requirements engineering challenges. We evaluate QAssist on a dataset covering three application domains and containing a total of 387 question-answer pairs. We experiment with state-of-the-art QA methods, based primarily on recent large-scale language models. In our empirical study, QAssist localizes the answer to a question to three passages within the requirements specification and within the external domain-knowledge resource with an average recall of 90.1% and 96.5%, respectively. QAssist extracts the actual answer to the posed question with an average accuracy of 84.2%. Index Terms—Natural-language Requirements, Question Answering (QA), Language Models, Natural Language Processing (NLP), Natural Language Generation (NLG), BERT, T5. [less ▲]

Wide-Beamwidth Circular Polarized Antenna for Diversity Combining Applications

in Vasquez-Peralvo, Juan Andres; Merlano Duncan, Juan Carlos; Eappen, Geoffrey (Eds.) et al Global Communications Conference, Rio de Janeiro, 4 - 9 December 2022 (in press)

This paper presents the design, simulation, and manufacturing of a right-hand circularly polarized antenna working in the frequency band 17.7-20.2 GHz with a beamwidth of 42.4$^\circ$ and 5.4$^\circ$ for ... [more ▼]

This paper presents the design, simulation, and manufacturing of a right-hand circularly polarized antenna working in the frequency band 17.7-20.2 GHz with a beamwidth of 42.4$^\circ$ and 5.4$^\circ$ for the H-plane and E-plane, respectively. The presented antenna is part of a set of three antennas, two high-gain antennas, and, presented in this paper, a low directive antenna used for reception. The application we describe in this paper combines the radio-frequency signals obtained from the O3b satellite constellation, using three antennas to apply path diversity later to reconstruct the original signal. Moreover, using an antenna with a beamwidth in one plane allows receiving two satellite signals at the same time, increasing by 3 dB the overall gain. The wide-band capabilities of the antenna are obtained using aperture coupling. In particular, the circular polarization of the antenna is generated using a truncated corner square patch. Further, a metasurface is placed at the top to enhance the axial ratio. Importantly, the simulation results obtained using CST Microwave Studio show that the antenna has a reflection coefficient below -10 dB and an axial ratio below -3 dB in the intended frequency range. [less ▲]

Project DragLiner: Harnessing plasma Coulomb drag for satellite deorbiting to keep orbits clean

Scientific Conference (in press)

Designing and managing an online, personalised research writing course for postgraduates

in Mcdiarmid, Carole (Ed.) Exploring pedagogical approaches in EAP teaching (in press)

This paper describes and evaluates a multidisciplinary, online research writing course for PhD students. First, we explain our course rationale and set-up. The core principles are personalised, self ... [more ▼]

This paper describes and evaluates a multidisciplinary, online research writing course for PhD students. First, we explain our course rationale and set-up. The core principles are personalised, self-regulated and peer learning, and the optimal use of class time. This is achieved through the following components: an e-coursebook developed in-house; tasks preparing students for the workshops; workshops; writing and reflection; peer review; and individual consultations. Next, we review participants’ feedback from course evaluation surveys. Many students liked the online format although most would prefer the peer review and discussion of theory to happen ‘offline’. A key finding for course efficacy is that students greatly valued working with their own examples in the workshops. They saw this and independent learning tasks as the greatest drivers of their writing development. They also benefited from multidisciplinary peer review. As regards the writing and reflection, all students chose to write on their own and the writing reflection tool was deemed ineffective. We furthermore discuss our (teachers’) perceptions of the affordances and challenges of this course format. On the one hand, it allows workshops to be devoted to collaborative tasks, reflection and data-driven learning. On the other hand, preparing such workshops is very time-consuming, while the multiple components and regular task submissions carry a heavy administrative burden. The paper concludes with how lessons learnt have been implemented into the current course configuration. [less ▲]

« … Eripuit servus mihi vitam » - Représentations médiatiques de la violence et de la criminalité dans les provinces occidentales de l'Empire romain

in Amodio, Mara (Ed.) The imagery of violence in Roman society (I-VI cent.). Persistence, innovations and interrelations from the Roman to the Christian Empire (in press)

Discrete-Phase Sequence Design with Stopband and PSL Constraints for Cognitive Radar

in Proceedings of EuRAD 2020 (in press)

We present the design of discrete-phase sequences considering simultaneously the peak sidelobe level (PSL) and avoiding reserved frequency bands which are occupied by narrowband interferers or ... [more ▼]

We present the design of discrete-phase sequences considering simultaneously the peak sidelobe level (PSL) and avoiding reserved frequency bands which are occupied by narrowband interferers or communications. We use the coordinate descent framework and propose an algorithm to design discrete-phase sequences with spectral power suppressed in arbitrary bands and with low auto-correlation sidelobes in terms of PSL. Our proposed algorithm exploits fast Fourier transform and is, therefore, computationally efficient. The over-the-air experiments using implementation on software-defined radio show reasonable agreement with numerical simulations and feasibility for field-deployment [less ▲]

The Rallye Platform: Mobile Location-based Serious Games for Digital Cultural Heritage

in Proceedings of the 25th International Conference on Human-Computer Interaction (HCI International) (in press)

Curves over finite fields and moduli spaces

in Curves over finite fields: past, present and future. (in press)

Les archevêques de Milan face aux premières expériences seigneuriales: stratégies et positionnements (milieu XIIIe-début XIVe s.)

in Barralis, Christine (Ed.) L’évêque face à son métier. Actes du colloque international, Metz. 15-17 novembre 2017 (in press)

Blockchain Governance: An Overview and Prediction of Optimal Strategies Using Nash Equilibrium

in 3rd AUE International Research Conference (in press)

Blockchain governance is a subject of ongoing research and an interdisciplinary view of blockchain governance is vital to aid in further research for establishing a formal governance framework for this ... [more ▼]

Blockchain governance is a subject of ongoing research and an interdisciplinary view of blockchain governance is vital to aid in further research for establishing a formal governance framework for this nascent technology. In this paper, the position of blockchain governance within the hierarchy of Institutional governance is discussed. Blockchain governance is analyzed from the perspective of IT governance using Nash equilibrium to predict the outcome of different governance decisions. A payoff matrix for blockchain governance is created and simulation of different strategy profiles is accomplished for computation of all Nash equilibria. We also create payoff matrices for different kinds of blockchain governance, which were used to propose novel mathematical formulae usable to predict the best governance strategy that minimizes the occurrence of a hard fork as well as predicts the behavior of the majority during protocol updates. [less ▲]

Von Objekt- und Meta-Ebenen: Analyse der Softwareanforderungen computergestützter juristischer Entscheidungen

in Recht DIGITAL – 25 Jahre IRIS, Proceedings of the International Legal Informatics Symposium (IRIS 2022) (in press)

Die Interpretation und Anwendung von Gesetzestexten auf einem konkreten Lebenssachverhalt erfordert von menschlichen Experten ein hohes Maß an Wissen, Erfahrung und die Fähigkeit zahlreiche kontextuelle ... [more ▼]

Die Interpretation und Anwendung von Gesetzestexten auf einem konkreten Lebenssachverhalt erfordert von menschlichen Experten ein hohes Maß an Wissen, Erfahrung und die Fähigkeit zahlreiche kontextuelle Überlegungen anzustellen. Die Formalisierung und Automatisierung solch eines Prozesses in einem computergestützten Verfahren muss dies entsprechend reflektieren. Ausgehend von einer Fallstudie werden in dieser Arbeit erforderliche juridische Schritte der Rechtsanwendung identifiziert und verschiedenen Objekt- und Meta-Ebenen zugeordnet. Diese Zuordnung erlaubt eine abstrakte Analyse von Softwareanforderungen, die juristische Assistenzsysteme erfüllen müssen, um bei juristischen Fallentscheidungen unterstützen zu können. [less ▲]

A Methodology for Handling Data Movements by Anticipation: Position Paper

in Euro-Par 2018 Workshops (in press)

The enhanced capabilities of large scale parallel and distributed platforms produce a continuously increasing amount of data which have to be stored, exchanged and used by various tasks allocated on ... [more ▼]

The enhanced capabilities of large scale parallel and distributed platforms produce a continuously increasing amount of data which have to be stored, exchanged and used by various tasks allocated on different nodes of the system. The management of such a huge communication demand is crucial for reaching the best possible performance of the system. Meanwhile, we have to deal with more interferences as the trend is to use a single all-purpose interconnection network whatever the interconnect (tree-based hierarchies or topology-based heterarchies). There are two different types of communications, namely, the flows induced by data exchanges during the computations, and the flows related to Input/Output operations. We propose in this paper a general model for interference-aware scheduling, where explicit communications are replaced by external topological constraints. Specifically, the interferences of both communication types are reduced by adding geometric constraints on the allocation of tasks into machines. The proposed constraints reduce implicitly the data movements by restricting the set of possible allocations for each task. This methodology has been proved to be efficient in a recent study for a restricted interconnection network (a line/ring of processors which is an intermediate between a tree and higher dimensions grids/torus). The obtained results illustrated well the difficulty of the problem even on simple topologies, but also provided a pragmatic greedy solution, which was assessed to be efficient by simulations. We are currently extending this solution for more complex topologies. This work is a position paper which describes the methodology, it does not focus on the solving part. [less ▲]

A New Perspective on the Luxembourgish Genitive

in Germanic Genitives (in press)

Maschinelles Lernen in der automatischen Auswertung von Punktwolken: Beispiele der Erfahrungen an der Universität Luxemburg

Scientific Conference (2023, October 07)

Intérêt de la participation des parents dans un modèle de Réponse à l’Intervention (RàI) ou dans un Système de Soutien à Paliers Multiples (SSPM) : une récension des écrits

Scientific Conference (2023, April 03)

Avec la démocratisation de l’enseignement et la multiplication des profils d’apprenants, l’institution scolaire a rapidement été confrontée à la nécessité d’étudier comment les besoins des élèves sont ... [more ▼]

Avec la démocratisation de l’enseignement et la multiplication des profils d’apprenants, l’institution scolaire a rapidement été confrontée à la nécessité d’étudier comment les besoins des élèves sont pris en compte par le système et comment les pratiques éducatives lui sont adaptées. C’est dans ce contexte qu’au début des années 2000, le modèle de réponse à l’intervention (RàI) a vu le jour. Il se définit comme une approche visant l’identification des élèves en difficulté et la mise en place d’une intervention ciblée sur les besoins de l’apprenant (Desrochers & Guay, 2020). Au fil des années, ce modèle RàI s’est intensifié et élargi à de nombreux domaines d’apprentissage mais aussi à la gestion du comportement des élèves. Cet élargissement du champ d’action initial a amené à renommer l’appellation de l’approche en Système de Soutien à Paliers Multiples (SSPM). Si la qualité de l’enseignement en classe et le soutien additionnel apporté aux élèves en difficulté semblent constituer le socle des interventions mobilisées dans le cadre du modèle RàI ou de l’approche en SSPM, il semble que l’engagement parental et la collaboration famille-école pourraient constituer un apport intéressant. En tant que premiers agents de socialisation de l’enfant et compte tenu de l’influence importante des familles sur la réussite développementale et éducative des enfants, la promotion de l’engagement parental et du partenariat famille-école présente un grand intérêt. Or, peu d’études ont, à ce jour, associé la facette famille à un modèle SSPM. Depuis plus de vingt années, l’engagement parental et le partenariat avec les parents constituent une thématique de recherche dont l’intérêt ne cesse de croître. Des synthèses récentes (par exemple, Axford et al., 2019 ; Englund et al., 2004 ; Kim et al., 2020, Roy & Giraldo-García, 2018 ; Huat See & Gorard, 2015), soulignent à quel point les relations école-famille ainsi que l’engagement parental peuvent avoir une influence significative et positive à la fois sur les performances scolaires mais aussi sur des variables conatives. Toutes ces études semblent converger vers le constat que la participation des parents a une influence positive sur la scolarité des élèves. Or, comme le rappellent Castro et al. (2015), ces études souffrent d’un manque d’homogénéisation des concepts à l’étude ; ce qui fait de la participation des parents un phénomène multiforme et multidimensionnel. En outre, il semble que peu d’études incluent un incitant à mettre en place une stratégie parentale particulière de soutien au cursus scolaire de l’enfant (Lawson, 2015). Cependant, il semble que l’école comme les familles se demandent quelles sont les façons les plus efficaces de collaborer pour optimiser les effets de l’engagement parental (Jeynes, 2012). Il apparait que le plus souvent les démarches et les actions sont davantage centrées sur l’école (Kanouté, 2006) qui tendent à placer les familles dans des rôles éducatifs mineurs (participation aux réunions de parents, par exemple). Toutefois, Garbacz et al. (2008) soutiennent qu’une approche d’implication parentale basée sur le partenariat favoriserait le renforcement des compétences des familles comme du personnel scolaire en identifiant et en soutenant les ressources des deux acteurs. Selon les auteurs, cette approche serait efficace car elle repose sur le principe d’une participation active des familles depuis l’identification des besoins, l’établissement de l’intervention et l’acquisition de nouvelles compétences plutôt que sur une réception passive d’une intervention externe faites par des professionnels. Ajoutons encore avec Larivée (2012) que pour renforcer l’efficacité des programmes d’implication parentale, il est important de concevoir les interventions en se référant aux données probantes de la recherche scientifique. Nous nous demandons si, par conséquent, le fait de renforcer la participation des parents dans la scolarité de leur enfant, au sein du modèle SSPM, dans le cadre d’un véritable partenariat école-famille autour d’une compétence d’apprentissage particulière, pourrait renforcer l’influence positive de ce soutien parental sur le développement scolaire de l’enfant tant au niveau des apprentissages scolaires (numératie et littératie) que de ses compétences socio-émotionnelles. C’est donc à travers une récension des écrits que nous cherchons à mettre en évidence l’intérêt de la participation des parents à un modèle de RàI ou une approche basée sur un SSPM. Pour réaliser cette synthèse, nous avons procédé de la façon suivante. Nous avons mené une recension de textes sur la participation des parents, le RàI ou le SSPM. Pour ce faire, nous avons eu recours à la base de données Education Research Complete. Nous avons utilisé les mots-clefs suivants : participation parentale, engagement parental ou investissement parental, Réponse à l’Intervention (RàI), Système de Soutien à Paliers Multiples (SSPM), numératie, littératie ou compétences socio-émotionnelles, ainsi que leur traduction en anglais : Response to intervention, Multi-tiered system of support, parental involvement ou parent engagement ou parent participation, numeracy, litteracy or Social-Emotional Learning (SEL). Les critères utilisés pour sélectionner les articles sont les suivants : 1) l’article est issu d’une revue à comité de lecture ; 2) l’article est disponible en langue française ou anglaise ; 3) l’article utilise une méthodologie qualitative et/ou quantitative étudiant l’intérêt d’une participation des parents dans un modèle RàI ou dans une approche en SSPM visant le développement de la numératie, de la littératie ou le développement socio-émotionnel chez des élèves du préscolaire et du primaire. Ce sont les résultats détaillés de cette récension d’écrits qui feront l’objet de la communication. Bibliographie Axford, N., Berry, V., Lloyd, J., Moore, D., Rogers, M., Hurst, A., Blockley, K., Durkin,H. and Minton, J. (2019) How Can Schools Support Parents’ Engagement in their Children’s Learning? Evidence from Research and Practice. London: Education Endowment Foundation. Report available from: https://educationendowmentfoundation.org.uk/evidence-summaries/evidence-reviews/parental-engagement/ (retrieved February 2022). Castro, M., Expósito-Casas, E., López-Martín, E., Lizasoain, L., Navarro-Asencio, E., & Gaviria, J. (2015). Parental involvement on student academic achievement: A meta-analysis. Educational Research Review, 14, 33-46. http://dx.doi.org/10.1016/j.edurev.2015.01.002 Englund, M. M., Luckner, A. E., Whaley, G. J. L., & Egeland, B. (2004). Children's Achievement in Early Elementary School: Longitudinal Effects of Parental Involvement, Expectations, and Quality of Assistance. Journal of Educational Psychology, 96(4), 723–730. https://doi.org/10.1037/0022-0663.96.4.723 Garbacz, S. & Woods, Kathryn & Swanger-Gagné, Michelle & Taylor, Ashley & Black, Kathryn & Sheridan, Susan. (2008). The Effectiveness of a Partnership-Centered Approach in Conjoint Behavioral Consultation. School Psychology Quarterly, 23(3), 313-326. 10.1037/1045-3830.23.3.313. Huat See, B., & Gorard, S. (2015). The role of parents in young people’s education—a critical review of the causal evidence. Oxford Review of Education, 41, 346-366. [less ▲]

Towards Log Slicing

in Dawes, Joshua; Shin, Donghwan; Bianculli, Domenico (Eds.) Towards Log Slicing (2023, April)

This short paper takes initial steps towards developing a novel approach, called log slicing, that aims to answer a practical question in the field of log analysis: Can we automatically identify log ... [more ▼]

This short paper takes initial steps towards developing a novel approach, called log slicing, that aims to answer a practical question in the field of log analysis: Can we automatically identify log messages related to a specific message (e.g., an error message)? The basic idea behind log slicing is that we can consider how different log messages are "computationally related" to each other by looking at the corresponding logging statements in the source code. These logging statements are identified by 1) computing a backwards program slice, using as criterion the logging statement that generated a problematic log message; and 2) extending that slice to include relevant logging statements. The paper presents a problem definition of log slicing, describes an initial approach for log slicing, and discusses a key open issue that can lead towards new research directions. [less ▲]

Continuer à faire réseau : le regard d’une chercheuse sur le projet Respadon (conclusion de la journée).

Scientific Conference (2023, March 13)

L’équipe de ResPaDon organise une journée d’échange autour des résultats et des perspectives de ce projet débuté en mars 2021. Des conditions d’accès aux collectes collaboratives, des enjeux juridiques à ... [more ▼]

L’équipe de ResPaDon organise une journée d’échange autour des résultats et des perspectives de ce projet débuté en mars 2021. Des conditions d’accès aux collectes collaboratives, des enjeux juridiques à la coopération entre acteurs nationaux et établissements de proximité, le Réseau de Partenaires pour l’exploration et l’analyse de données numériques (ResPaDon) propose de partager les résultats de sa démarche pour développer les usages scientifiques de la collection des archives du dépôt légal du web. [less ▲]

Lehrer-Schüler-Beziehungen: Von der Generalisierbarkeit positiver Befunde

Scientific Conference (2023, March 01)

Zahlreiche Studien zeigen Zusammenhänge zwischen positiven Lehrer-Schüler-Beziehungen und Ergebnisvariablen im schulischen Kontext (z.B. Noten, wahrgenommene Leistung, soziales Verhalten, Lernmotivation ... [more ▼]

Zahlreiche Studien zeigen Zusammenhänge zwischen positiven Lehrer-Schüler-Beziehungen und Ergebnisvariablen im schulischen Kontext (z.B. Noten, wahrgenommene Leistung, soziales Verhalten, Lernmotivation; Givens Rolland, 2012; Korpershoek et al., 2016). Hierbei werden Lehrer-Schüler-Beziehungen ganz unterschiedlich konzeptualisiert: Während die Lehrer-Schüler-Interaktion vor allem den praktischen Austausch zwischen Lehrkraft und Schüler*in betrachtet (z.B. Beteiligung am Unterrichtsgespräch), verbindet die konstruktive Unterstützung durch die Lehrkraft unterrichtliche und inhaltliche Unterstützung mit der Wärme und Qualität der Lehrer-Schüler-Beziehung (vgl. Decristan et al., 2022; Endedijk et al., 2021; Hamre & Pianta, 2001). Beide Aspekte sind bedeutend für den schulischen Lernerfolg (Endedijk et al., 2021). Vor dem Hintergrund zahlreicher Befunde stellt sich die Frage der Generalisierbarkeit von Effekten positiver Lehrer-Schüler-Beziehungen und -Interaktionen: Profitieren alle Schüler*innen gleichermaßen von emotionaler Nähe und Freundlichkeit der Lehrkraft? Oder zeigen sich Unterschiede, beispielsweise zwischen Jungen und Mädchen oder Schüler*innen verschiedenen Alters, inwieweit sich positive Lehrer-Schüler-Beziehungen auf Ergebnisvariablen auswirken? Auch die meta-analytische Literatur ist sich in diesen Fragen teilweise uneins (vgl. Lei et al., 2016; Roorda et al., 2017). Offen bleibt zudem, welche Schüler*innen besondere Nachteile haben bei einer negativen Lehrer-Schüler-Beziehung (Nurmi, 2012). Unser Symposium zeichnet ein umfassendes Bild dieser wichtigen Beziehung und Interaktion im Herzen der schulischen Bildung anhand der Generalisierbarkeit gefundener Effekte: Der erste Beitrag (Emslander et al., 2023) vergleicht die Rolle der elterliche Unterstützung mit der Unterstützung durch die Lehrkraft auf die akademische Entwicklung der Schüler*innen. Die umfangreiche längsschnittliche Studie verwendet Daten von Haupt-, Real- und Mittelschulen über einen Zeitraum von vier Jahren in der Adoleszenz. Ein Augenmerk liegt auf Unterschieden in den Zusammenhängen zwischen der fünften und achten Klasse. Der zweite Beitrag untersucht den Einfluss der Fehlerkultur bei der Beteiligung am Unterrichtsgespräch. Mithilfe von Videodaten werden Unterrichtsstunden in Mathematik und Deutsch untersucht. Die Studie untersucht differenzielle Befunde der Zusammenhänge in Abhängigkeit des Selbstkonzepts und Migrationshintergrunds von Schüler*innen. Ein dritter Beitrag beschäftigt sich mit dem moderierenden Einfluss der Schülerwahrnehmung von konstruktiven Lehrkraftunterstützung in der Sekundarstufe und ihrem Zusammenhang zu mathematischen Selbstkonzept und Interesse. Das besondere Augenmerk dieser Studie liegt auf den Unterschieden in der Motivation von jungen Frauen und Männern für das Fach Mathematik. Abschließend bietet ein vierter Beitrag einen Überblick über Korrelate von Lehrer-Schüler-Beziehungen in der Literatur. Das systematische Review von Meta-Analysen illustriert Zusammenhänge, Moderatoren und Studienqualität auf dem Gebiet der Lehrer-Schüler-Beziehungen. Besonders werden Alter und Geschlecht der Schüler*innen ebenso wie wer die Lehrer-Schüler-Beziehung einschätzt kontrovers diskutiert. LITERATUR Decristan, J., Kunter, M., & Fauth, B. (2022). Die Bedeutung individueller Merkmale und konstruktiver Unterstützung der Lehrkraft für die soziale Integration von Schülerinnen und Schülern im Mathematikunterricht der Sekundarstufe. Zeitschrift für Pädagogische Psychologie, 36(1–2), 85–100. https://doi.org/10.1024/1010-0652/a000329 Emslander, V., Holzberger, D., Fischbach, A., & Scherer, R. (2023, January 3). Lehrer-Schüler-Beziehungen und ihre Korrelate: Ein systematisches Review von Meta-Analysen [Teacher-Student Relationships and their Correlates: A systematic Review of Meta-Analyses]. In Emslander, V., & Holzberger, D. (Eds.) (2023, February 28 – March 2). Lehrer-Schüler-Beziehungen: Von der Generalisierbarkeit positiver Befunde [Teacher-Student Relationships: Of the Generalizability of Positive Results]. Symposium at the 10th Conference of the Society for Empirical Educational Research (GEBF), Essen, Germany. http://hdl.handle.net/10993/54530 Endedijk, H. M., Breeman, L. D., van Lissa, C. J., Hendrickx, M. M. H. G., den Boer, L., & Mainhard, T. (2021). The Teacher’s Invisible Hand: A Meta-Analysis of the Relevance of Teacher–Student Relationship Quality for Peer Relationships and the Contribution of Student Behavior. Review of Educational Research, 92(3). https://doi.org/10.3102/00346543211051428 Givens Rolland, R. (2012). Synthesizing the Evidence on Classroom Goal Structures in Middle and Secondary Schools: A Meta-Analysis and Narrative Review. Review of Educational Research, 82(4), 396–435. https://doi.org/10.3102/0034654312464909 Hamre, B. K., & Pianta, R. C. (2001). Early Teacher-Child Relationships and the Trajectory of Children’s School Outcomes through Eighth Grade. Child Development, 72(2), 625–638. https://doi.org/10.1111/1467-8624.00301 Korpershoek, H., Harms, T., de Boer, H., van Kuijk, M., & Doolaard, S. (2016). A Meta-Analysis of the Effects of Classroom Management Strategies and Classroom Management Programs on Students’ Academic, Behavioral, Emotional, and Motivational Outcomes. Review of Educational Research, 86(3), 643–680. https://doi.org/10.3102/0034654315626799 Lei, H., Cui, Y., & Chiu, M. M. (2016). Affective Teacher—Student Relationships and Students’ Externalizing Behavior Problems: A Meta-Analysis. Frontiers in Psychology, 7. https://doi.org/10.3389/fpsyg.2016.01311 Nurmi, J.-E. (2012). Students’ characteristics and teacher–child relationships in instruction: A meta-analysis. Educational Research Review, 7(3), 177–197. https://doi.org/10.1016/j.edurev.2012.03.001 Roorda, D. L., Jak, S., Zee, M., Oort, F. J., & Koomen, H. M. Y. (2017). Affective Teacher–Student Relationships and Students’ Engagement and Achievement: A Meta-Analytic Update and Test of the Mediating Role of Engagement. School Psychology Review, 46(3), 239–261. https://doi.org/10.17105/SPR-2017-0035.V46-3 [less ▲]

Diversifikation im Klassenzimmer – ein Einwegspiegel?

Scientific Conference (2023, March 01)

Regional heterogeneity and individual characteristics in the development of a European tax policy: historical insights from Luxembourg

in Danescu, Elena; Dima, Alina Mihaela (Eds.) Fostering recovery through metaverse business modelling - An interdisciplinary analysis of the new paradigm shift (2023, March)

Luxembourg is currently one of the most politically stable, consensus-oriented, and prosperous countries in the world, characterised by am advanced social market economy, and a level of material wellbeing ... [more ▼]

Luxembourg is currently one of the most politically stable, consensus-oriented, and prosperous countries in the world, characterised by am advanced social market economy, and a level of material wellbeing above the EU average. Its strong fiscal position is well illustrated by a longstanding AAA credit rating, a significant accumulation of government financial assets, and a distinct fiscal approach. In this light, this paper aims to investigate the specific features of the tax system in Luxembourg from a multidisciplinary perspective by analysing historical sources and exploring the development of these particularities over time, their impact on the socioeconomic context and their repercussions for the European integration process, especially in the design and completion of Economic and Monetary Union (EMU). [less ▲]

Die Grenzen aufgezeigt:Technische Innovation und räumliche Abstraktion am Beispiel früher Landkarten der Grenzregion zwischen dem Herzogtum Luxemburg und dem Kurfürstentum Trier

in Schröder, Lina; Wegewitz, Markus (Eds.) Europäische Grenzregionen. Neue Wege im Umgang mit historischen Raum- und Grenzkonzeptionen in der Geschichtswissenschaft (2023, March)

Die Ausbildung und Verfestigung der kurtrierischen und luxemburgischen Landesherrschaften war im 14. Jahrhundert weitgehend zum Abschluss gekommen. Die Transformation vom Personenverbands- zum ... [more ▼]

Die Ausbildung und Verfestigung der kurtrierischen und luxemburgischen Landesherrschaften war im 14. Jahrhundert weitgehend zum Abschluss gekommen. Die Transformation vom Personenverbands- zum Flächenstaat frühneuzeitlicher Prägung hatte die Ausbildung einer zunehmend deutlicheren Grenze zwischen beiden Territorien zur Folge. Ebenso formierte sich auch eine Grenze im Grenzraum mit Frankreich und Lothringen. Die vereinfachende Darstellung komplexer teils überlagerter Grenzzonen in Form von abstrahierenden Linien musste von den zeitgenössischen Kartographen jedoch erst noch entwickelt werden. Die älteste regionale Karte mit einer angedeuteten partiellen Grenzmarkierung stammt aus dem Jahr 1555. Eine zunehmende Professionalisierung der Kartographie gelang ab der zweiten Hälfte des 16. Jahrhunderts durch Landesaufnahmen, initiiert von den jeweiligen Landesherren. Die Intention der Auftraggeber war dabei ähnlich: einerseits sollte das jeweilige Territorium durch die Karte möglichst als geschlossen beherrschter Raum dargestellt werden, andererseits galt es, die bisher nur verbal beschriebenen teils strittigen Grenzen als abstrakte Linien deutlich sichtbar zu machen. Die Karten der Landesaufnahmen waren zunächst geheim, dennoch fanden sie bereits nach wenigen Jahren Eingang in die Atlanten von Ortelius, de Jode und Mercator. Diese beeinflussten wiederum die Karten der Region in den späteren Atlanten der niederländischen, französischen und süddeutschen Kartenverleger. Der Beitrag beschreibt, ab wann und in welcher Form Grenzen in frühen Karten (16.-18. Jahrhundert) dargestellt wurden. Besonders in den Blick genommen wird der Prozess der Ausbildung von Linien zur abstrakten Darstellung unklarer, teils strittiger Grenzräume sowie die zunehmende Professionalisierung und Genauigkeit in der kartographischen Darstellung durch Vermessungen im Feld. [less ▲]

Lernstörung oder Sprachbarriere? – Entwicklung eines für Luxemburg angepassten Wortschatztests

Poster (2023, February 24)

Table ronde : L'historiographie de l'histoire des relations internationales en Belgique 1950-1970

Scientific Conference (2023, February 17)

Explorers presenter

Scientific Conference (2023, February 01)

Exploring the Embodied Experience of Walking Meetings through Bodystorming – Implications for Design

in TEI'23 Seventeenth International Conference on Tangible, Embedded, and Embodied Interaction (2023, February)

Walking meetings are a promising way to reduce unhealthy sedentary behavior at the office. Some aspects of walking meetings are however hard to assess using traditional research approaches that do not ... [more ▼]

Walking meetings are a promising way to reduce unhealthy sedentary behavior at the office. Some aspects of walking meetings are however hard to assess using traditional research approaches that do not account well for the embodied experience of walking meetings. We conducted a series of 16 bodystorming sessions, featuring unusual walking meeting situations to engage participants (N=45) in a reflective experience. After each bodystorming, participants completed three tasks: a body map, an empathy map, and a rating of workload using the NASA-TLX scale. These embodied explorations provide insights on key themes related to walking meetings: material and tools, physical and mental demand, connection with the environment, social dynamics, and privacy. We discuss the role of technology and opportunities for technology-mediated walking meetings. We draw implications for the design of walking meeting technologies or services to account for embodied experiences, and the individual, social, and environmental factors at play. [less ▲]

Bringing Movement to Digital Tasks at the Office: Designing an Acceptably Active Interface Interaction for Sending Emails

in Proceedings of the Seventeenth International Conference on Tangible, Embedded, and Embodied Interaction TEI'23 (2023, February)

While working on a computer typically involves sitting for prolonged periods of time, sedentary work routines are associated with numerous health issues. To address this societal concern, existing ... [more ▼]

While working on a computer typically involves sitting for prolonged periods of time, sedentary work routines are associated with numerous health issues. To address this societal concern, existing solutions trigger physical activity as a break from work, rather than a part of it. In this research, we explore a vision for physically active ways of working, by transforming mundane digital tasks into physically active ones. As a research artifact and design exemplar, we present A2-I2, an innovative tangible system for sending emails. After loading their email onto a physical “letter” token, office workers must walk to a physical mailbox located in the office space. Understanding what design qualities influence the experience and acceptability of such systems is a necessary step toward the design of acceptably active interface interactions. We report on a preliminary user test with 8 participants. With this project, we aim to inspire future tangible and embodied systems addressing the timely issue of sedentary behavior at work. [less ▲]

Breakthrough of directional statistics in space science

Scientific Conference (2023, January 24)

It should be no surprise that already back in the 17-18th centuries important foundations of modern statistical theory were formulated to address astronomical problems, the astronomers were the ... [more ▼]

It should be no surprise that already back in the 17-18th centuries important foundations of modern statistical theory were formulated to address astronomical problems, the astronomers were the statisticians. For instance the 'almost coincidence' in the orbits of the planets in our Solar System with the ecliptic has intrigued the scientists for a long time. Even D. Bernoulli (in the 1730's) wondered if this fact could happen 'by chance'. In a statistical framework, one could think of using a uniformity test on the sphere. Testing isotropy or, equivalently, testing uniformity on the unit hypersphere is one of the oldest as well as most fundamental problems in directional statistics and it is still much considered nowadays. Furthermore with the increasing astronomical data, innovative modern directional statistical theories and models have been proposed to deal with space science issues such as tracking space objects. In this talk, we will provide a review of the many old and recent developments of directional statistics animated by interesting applications in space science. This is a joint work with Christophe Ley. [less ▲]

The Ugly Truth of Realistic Perception in Vehicular Simulations

Poster (2023, January 08)

Automated vehicles use sensors to perceive the environment, and studies have shown the limitations of these sensors. The onboard sensors may not detect objects when other participants occlude the Field of ... [more ▼]

Automated vehicles use sensors to perceive the environment, and studies have shown the limitations of these sensors. The onboard sensors may not detect objects when other participants occlude the Field of View (FoV). Thus, sensor efficiency must be tested to ensure its reliability. Simulation is an excellent test option due to the complexity associated with practical experiments. However, emerging simulation frameworks still have various limitations, especially when it comes to large-scale evaluation. This work investigates realistic perception simulation options for autonomous vehicles. We report the perception accuracy for different traffic scenarios. [less ▲]

Federated Learning for Credit Risk Assessment

in Proceedings of the 56th Hawaii International Conference on System Sciences (2023, January 03)

Credit risk assessment is a standard procedure for financial institutions (FIs) when estimating their credit risk exposure. It involves the gathering and processing quantitative and qualitative datasets ... [more ▼]

Credit risk assessment is a standard procedure for financial institutions (FIs) when estimating their credit risk exposure. It involves the gathering and processing quantitative and qualitative datasets to estimate whether an individual or entity will be able to make future required payments. To ensure effective processing of this data, FIs increasingly use machine learning methods. Large FIs often have more powerful models as they can access larger datasets. In this paper, we present a Federated Learning prototype that allows smaller FIs to compete by training in a cooperative fashion a machine learning model which combines key data derived from several smaller datasets. We test our prototype on an historical mortgage dataset and empirically demonstrate the benefits of Federated Learning for smaller FIs. We conclude that smaller FIs can expect a significant performance increase in their credit risk assessment models by using collaborative machine learning. [less ▲]

Astute Approach to Handling Memory Layouts of Regular Data Structures

in Algorithms and Architectures for Parallel Processing (2023, January)

Programmers of high-performance applications face many challenging aspects of contemporary hardware architectures. One of the critical aspects is the efficiency of memory operations which is affected not ... [more ▼]

Programmers of high-performance applications face many challenging aspects of contemporary hardware architectures. One of the critical aspects is the efficiency of memory operations which is affected not only by the hardware parameters such as memory throughput or cache latency but also by the data-access patterns, which may influence the utilization of the hardware, such as re-usability of the cached data or coalesced data transactions. Therefore, a performance of an algorithm can be highly impacted by the layout of its data structures or the order of data processing which may translate into a more or less optimal sequence of memory operations. These effects are even more pronounced on highly-parallel platforms, such as GPUs, which often employ specific execution models (lock-step) or memory models (shared memory). In this work, we propose a modern, astute approach for managing and implementing memory layouts with first-class structures that is very efficient and straightforward. This approach was implemented in Noarr, a GPU-ready portable C++ library that utilizes generic programming, functional design, and compile-time computations to allow the programmer to specify and compose data structure layouts declaratively while minimizing the indexing and coding overhead. We describe the main principles on code examples and present a performance evaluation that verifies our claims regarding its efficiency. [less ▲]

Non-Standard errors

Scientific Conference (2023, January)

Results - TRB

Scientific Conference (2023)

Towards assimilating SAR data into an anisotropic model of an underground aquifer

Scientific Conference (2023)

In this study, we aim to shed light on the feasibility of assimilating synthetic aperture radar (SAR) data into a partial differential equation-based model of a poroelastic homogeneous aquifer with ... [more ▼]

In this study, we aim to shed light on the feasibility of assimilating synthetic aperture radar (SAR) data into a partial differential equation-based model of a poroelastic homogeneous aquifer with anisotropic hydraulic conductivity (AHC). Although other authors [1] have considered the problem of assimilating SAR data into a poroelastic model that uses an inhomogeneous isotropic random field model for hydraulic conductivity, to the best of our knowledge, our study is the first to consider assimilating SAR data into a poroelastic model with AHC. Our study is inspired by the work of [2] where an aquifer test is performed on the Anderson Junction aquifer in southwestern Utah. Due to the inherent preferential direction of the fractured sandstone at the Anderson Junction site, the ratio of hydraulic conductivity along the principal axes can be on the order of 24 to 1. We build an anisotropically conductive poroelastic finite element model of the Anderson Junction site that can predict the coupled fluid flow and mechanical displacements. Our results show that the effective elastic response of the aquifer on the Earth’s surface has an anisotropic nature driven by the underlying anisotropy in the fluid problem, even when the elasticity problem is assumed to be isotropic. We interpret these results in the context of using SAR data to improve the characterization of aquifer systems, like the Anderson Junction site, with strongly anisotropic behavior. The Doctoral Training Unit Data-driven computational modelling and applications (DRIVEN) is funded by the Luxembourg National Research Fund under the PRIDE programme (PRIDE17/12252781). [1] Amal Alghamdi. Bayesian inverse problems for quasi-static poroelasticity with application to ground water aquifer characterization from geodetic data. PhD thesis, 2020. https://repositories.lib.utexas.edu/handle/2152/86231. [2] Victor M. Heilweil and Paul A. Hsieh. Determining Anisotropic Transmissivity Using a Simplified Papadopulos Method. Groundwater, 44(5):749–753, 2006. 10.1111/j.1745-6584.2006.00210.x [less ▲]

You Can Dance! Generating Music-Conditioned Dances on Real 3D Scans.

Scientific Conference (2023)

Efficient Hessian-based DNN Optimization via Chain-Rule Approximation

in Proceedings of the 6th Joint International Conference on Data Science Management of Data (10th ACM IKDD CODS and 28th COMAD) (2023)

Exploring the potential of Google Popular Times for transit demand estimation

Scientific Conference (2023)

SoK: Secure E-Voting with Everlasting Privacy

in Proceedings on Privacy Enhancing Technologies (PoPETs) (2023)

Vote privacy is a fundamental right, which needs to be protected not only during an election, or for a limited time afterwards, but for the foreseeable future. Numerous electronic voting (e-voting ... [more ▼]

Vote privacy is a fundamental right, which needs to be protected not only during an election, or for a limited time afterwards, but for the foreseeable future. Numerous electronic voting (e-voting) protocols have been proposed to address this challenge, striving for everlasting privacy. This property guarantees that even computationally unbounded adversaries cannot break privacy of past elections. The broad interest in secure e-voting with everlasting privacy has spawned a large variety of protocols over the last three decades. These protocols differ in many aspects, in particular the precise security properties they aim for, the threat scenarios they consider, and the privacy-preserving techniques they employ. Unfortunately, these differences are often opaque, making analysis and comparison cumbersome. In order to overcome this non-transparent state of affairs, we systematically analyze all e-voting protocols designed to provide everlasting privacy. First, we illustrate the relations and dependencies between all these different protocols. Next, we analyze in depth which protocols do provide secure and efficient approaches to e-voting with everlasting privacy under realistic assumptions, and which ones do not. Eventually, based on our extensive and detailed treatment, we identify which research problems in this field have already been solved, and which ones are still open. Altogether, our work offers a well-founded reference point for conducting research on secure e-voting with everlasting privacy as well as for future-proofing privacy in real-world electronic elections. [less ▲]

Beam Splash Mitigation for NGSO Spectrum Coexistence between Feeder and User Downlink

in International ITG 26th Workshop on Smart Antennas (WSA), Braunschweig, Germany, 27 Feb - 03 Mar 2023. (2023)

ADDRESSING THE IMPACT OF MAINTENANCE IN SHUNTING OPERATIONS THROUGH SHUNT-IN POLICIES FOR FREIGHT TRAINS OPERATIONS.

Scientific Conference (2023)

Deep Learning-Based Device-Free Localization in Wireless Sensor Networks

Scientific Conference (2023)

Location-based services are witnessing a rise in popularity owing to their key features of delivering personalized digital experience. The recent developments in wireless sensing techniques make the ... [more ▼]

Location-based services are witnessing a rise in popularity owing to their key features of delivering personalized digital experience. The recent developments in wireless sensing techniques make the realization of device-free localization (DFL) feasible within wireless sensor network (WSN) architectures. The DFL is an emerging technology that utilizes radio signal information for detecting and positioning a passive movable target without attached devices. However, determining the characteristics of the massive raw signals and extracting meaningful discriminative features relevant to the localization are highly intricate tasks due to the different patterns associated with different locations. To overcome these issues, deep learning (DL) techniques can be utilized here owing to their remarkable performance gains in similar practical problems. In this direction, we propose a DFL framework consists of multiple convolutional neural network (CNN) layers along with deep autoencoders based on the restricted Boltzmann machines (RBM) to construct a convolutional deep belief network (CDBN) for features recognition and extracting. Each CNN layer has stochastic pooling to sample down the feature map and reduced the dimensions of the required data without losing important information. This dimensionality reduction can alleviate the heavy computation while ensuring precise localization. The proposed framework is validated using real experimental dataset. The results show that the proposed model is able to achieve a high accuracy of 98% with reduced data dimensions and low signal-to-noise ratios (SNRs). [less ▲]

Connecting culture to geometry - problem based learning across subjects

Scientific Conference (2022, December 16)

Symbols are used to visualise and understand abstract mathematical concepts. According to Duval (1999), visualisations are the core of understanding mathematics and creating a visualisation involves ... [more ▼]

Symbols are used to visualise and understand abstract mathematical concepts. According to Duval (1999), visualisations are the core of understanding mathematics and creating a visualisation involves reasoning and construction. This is also common in culture, for example, in religions where internalisation and externalisation are used for reflection (Vicini, 2017) that might be a visualisation such as geometric art. We want to create learning situations for problem based learning useful for various subjects (i.e., mathematics, history, culture, arts) in primary school based on geometrical shapes. Geometrical shapes are among symbols used in human beliefs (e.g., the cross in Christianity, the star of David in Judaism or the wheel of law in Buddhism) and can be found on buildings and several school books. Visualisations, e.g. in Islam, can be based on polygons, stars or rosettas (Abdullahi & Embi, 2013). Lesson plans combining cultural subjects such as history or art with mathematics are not common, but we believe there is a visible connection with geometric art. Therefore, we aim to find out whether teachers from subjects with a cultural background are interested in such lesson plans and which attributes they should have to combine the subject, geometry and technology in a maker-centred learning experience (Michael & Jones, 2020). We plan on a qualitative approach, first introducing an activity and then interviewing primary school children and their teachers for their perceptions and learnings. For a first orientation of attributes and teacher needs, we created an activity to develop bookmarks in 2D and 3D using chequered paper and the 3D modelling software TinkerCAD for over 50 primary school students. The lesson plan and comments of the student's teachers hinting towards attributes will be presented, and future steps will be discussed. [less ▲]

Smart charging of EVs: Would you share your data for money?

Scientific Conference (2022, December 11)

Many governments worldwide aim to eventually replace most combustion engines on the roads with electric vehicles (EVs). But this change causes an additional load on the electrical grid, especially if many ... [more ▼]

Many governments worldwide aim to eventually replace most combustion engines on the roads with electric vehicles (EVs). But this change causes an additional load on the electrical grid, especially if many EVs are charged simultaneously at peak times. Smart charging is a solution to better distribute the load throughout the day or night, while considering consumer preferences. For home charging, the idea is for EV users to always plug in their EVs when they are at home, and for the energy supplier to then decide when to charge which EV. By using (sensitive) consumer data, such as charging history, location of the smartphone and calendar information, the energy supplier can plan and optimize the charging of the EVs even better. In a survey, we seek to understand which of these data consumers are willing to share for smart charging, and what factors, such as privacy concerns and data sharing habits, influence this decision. Furthermore, in an experiment within the survey, we investigate whether consumers are more willing to share data if they receive monetary incentives. Our research design is based on the theoretical framework of Barth and de Jong (2017). 20 participants took part in the pretest, after which we adjusted the survey. We then shared the survey through various channels. [less ▲]

“When publics co-produce history in museums: skills, methodologies and impact of participation”

Scientific Conference (2022, December 07)

School tracking in Luxembourg: the longitudinal impact of student characteristics and school composition

Scientific Conference (2022, December 05)

Research question: The current study aimed to investigate the influence of student and school level factors on school tracking in secondary education. We were especially interested in the association ... [more ▼]

Research question: The current study aimed to investigate the influence of student and school level factors on school tracking in secondary education. We were especially interested in the association between student characteristics and school composition in Grade 3 and school track in Grade 9. Data source: Data were collected as part of the Luxembourg school monitoring programme “Épreuves Standardisées” (ÉpStan; Fischbach et al., 2014). The study cohort include all students enrolled in the Luxembourg public education system in Grade 3 in November 2013 combined with data from the same students in Grade 9 in November 2017-2019 for students following advanced or regular educational pathways, completed with data from November 2020 and 2021 for students that repeated once or twice (N≈3600). Theoretical approach: The study draws upon theoretical frameworks and empirical findings (e.g., Boudon, 1974; Bourdieu, 1984), that have demonstrated students´ socio-demographic characteristics are associated with (dis)advantages for specific groups of students in education systems as well as more recent work focusing on school composition (e.g., Baumert et al., 2006), especially as tracked school systems are known to be prone to social segregation (e.g., Hadjar & Gross, 2016). To date, most research on school segregation in tracked education systems such as Luxembourg has focused on individual student´s characteristics. However, with increasing heterogeneity of student cohorts and known differences in educational opportunities related to the social and ethnic composition of the school’s student body (e.g., Thrupp et al., 2002), the current research extents the existing literature by considering both individual (including prior academic achievement and socio-demographic characteristics) and school level factors (mean academic level and percentage of students from lower socio-economic and migration background) in predicting school track placement. Main findings: Results of a multilevel random effect logistic regression analysis in which we estimated marginal effects on the probability to be placed in the highest, middle or lowest track in Luxembourg show that even after controlling for student´s academic achievement, track placement is affected by the gender and socio-economic background of the student, whereby boys and students from low SES families have less chance to be placed in the highest track. The association with socio-economic background is not only visible on the student level but also on school level, whereby students attending primary schools with a higher percentage of low SES families have less chance to be orientated to the higher track compared to the middle track, regardless of the student´ individual academic performance. [less ▲]

CODEBERT-NT: code naturalness via CodeBERT

in 22nd IEEE International Conference on Software Quality, Reliability and Security (QRS'22) (2022, December 05)

Much of recent software-engineering research has investigated the naturalness of code, the fact that code, in small code snippets, is repetitive and can be predicted using statistical language models like ... [more ▼]

Much of recent software-engineering research has investigated the naturalness of code, the fact that code, in small code snippets, is repetitive and can be predicted using statistical language models like n-gram. Although powerful, training such models on large code corpus can be tedious, time consuming and sensitive to code patterns (and practices) encountered during training. Consequently, these models are often trained on a small corpus and thus only estimate the language naturalness relative to a specific style of programming or type of project. To overcome these issues, we investigate the use of pre-trained generative language models to infer code naturalness. Pre-trained models are often built on big data, are easy to use in an out-of-the-box way and include powerful learning associations mechanisms. Our key idea is to quantify code naturalness through its predictability, by using state-of-the-art generative pre-trained language models. Thus, we suggest to infer naturalness by masking (omitting) code tokens, one at a time, of code-sequences, and checking the models’ability to predict them. We explore three different predictability metrics; a) measuring the number of exact matches of the predictions, b) computing the embedding similarity between the original and predicted code, i.e., similarity at the vector space, and c) computing the confidence of the model when doing the token completion task regardless of the outcome. We implement this workflow, named CODEBERT-NT, and evaluate its capability to prioritize buggy lines over non-buggy ones when ranking code based on its naturalness. Our results, on 2,510 buggy versions of 40 projects from the SmartShark dataset, show that CODEBERT-NT outperforms both, random-uniform and complexity-based ranking techniques, and yields comparable results to the n-gram models. [less ▲]

Dynamic Beam-Layout Design for MEO High Throughput Satellite Systems

Scientific Conference (2022, December 04)

We propose a traffic-oriented beam-layout optimization framework for a medium Earth orbit (MEO) high throughput satellite (HTS) system. The designed beam-layout plans have the objective of dynamic traffic ... [more ▼]

We propose a traffic-oriented beam-layout optimization framework for a medium Earth orbit (MEO) high throughput satellite (HTS) system. The designed beam-layout plans have the objective of dynamic traffic load balancing with minimal radio resource management. We model and evaluate the high directivity and the high reconfigurability capabilities of next-generation HTS systems that are equipped with a processing power on board. The resulting payload flexibility is compared numerically against the on-ground counterpart. Adequate key performance indicators, such as the Jain’s fairness index, the load distribution gap and optimization convergence time, are used to benchmark the system against state-of-the-art solutions. Results show that a dynamic HTS in MEO is capable of efficiently attaining high quality load balancing performance under realistic spatiotemporally varying traffic demands. [less ▲]

Faster and Cheaper Energy Demand Forecasting at Scale

in Has it Trained Yet? Workshop at the Conference on Neural Information Processing Systems (2022, December 02)

Energy demand forecasting is one of the most challenging tasks for grids operators. Many approaches have been suggested over the years to tackle it. Yet, those still remain too expensive to train in terms ... [more ▼]

Energy demand forecasting is one of the most challenging tasks for grids operators. Many approaches have been suggested over the years to tackle it. Yet, those still remain too expensive to train in terms of both time and computational resources, hindering their adoption as customers behaviors are continuously evolving. We introduce Transplit, a new lightweight transformer-based model, which significantly decreases this cost by exploiting the seasonality property and learning typical days of power demand. We show that Transplit can be run efficiently on CPU and is several hundred times faster than state-of-the-art predictive models, while performing as well. [less ▲]

DRIVE-B5G: A Flexible and Scalable Platform Testbed for B5G-V2X Networks

in DRIVE-B5G: A Flexible and Scalable Platform Testbed for B5G-V2X Networks (2022, December)

Unlike previous mobile networks, 5G and beyond (B5G) networks are expected to be the key enabler of various vertical industries such as eHealth, intelligent transportation, and Industrial IoT verticals ... [more ▼]

Unlike previous mobile networks, 5G and beyond (B5G) networks are expected to be the key enabler of various vertical industries such as eHealth, intelligent transportation, and Industrial IoT verticals. To support that, B5G networks enable to sharing of common physical resources (radio, computation, network) among different tenants, thanks to network slicing concept and network softwarization technologies, including Software Defined Networking (SDN) and Network Function Virtualization (NFV). Therefore, new research challenges related to B5G networks have emerged, such as resources management and orchestration, service chaining, security, and QoS management. However, there is a lack of a realistic platform enabling researchers to design and validate their solutions effectively, since B5G networks are still in their early stages. In this paper, we first discuss the different methods for deploying realistic B5G platforms for the V2X vertical, including the key B5G technologies. Then, we describe DRIVE-B5G, a novel platform that serves as an end-to-end test-bed to emulate a vehicular network environment, allowing researchers to provide proof of concept, validate, and evaluate their research approaches. [less ▲]

Les nouvelles infractions de droit pénal sexuel : le voyeurisme, la diffusion non consentie de contenus à caractère sexuel, l’approche d’un mineur à des fins sexuelles et l’outrage public aux bonnes moeurs

in Delhaise, Elise; Colette-Basecqz, Nathalie; Henrion, Thomas (Eds.) et al Actualités en matière de droit pénal sexuel (2022, December)

Hybrid Active-Passive Reconfigurable IntelligentSurface-Assisted UAV Communications

Poster (2022, December)

We consider a novel hybrid active-passive reconfigurable intelligent surface (RIS)-assisted unmanned aerial vehicle (UAV) air-ground communications system. Unlike the conventional passive RIS, the hybrid ... [more ▼]

We consider a novel hybrid active-passive reconfigurable intelligent surface (RIS)-assisted unmanned aerial vehicle (UAV) air-ground communications system. Unlike the conventional passive RIS, the hybrid RIS is equipped with a few active elements to not only reflect but also amplify the incident signals for significant performance improvement. Towards a fairness design, our goal is to maximize the minimum rate among users through jointly optimizing the location and power allocation of the UAV and the RIS reflecting/amplifying coefficients. The formulated optimization problem is nonconvex and challenging, which is efficiently solved via block coordinate descend and successive convex approximation. Our numerical results show that a hybrid RIS requires only 4 active elements and a power budget of 0 dBm to achieve an improvement of 52.08% in the minimum rate, while that achieved by a conventional passive RIS with the same total number of elements is only 18.06%. [less ▲]