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See detailWide-Beamwidth Circular Polarized Antenna for Diversity Combining Applications
Vasquez-Peralvo, Juan Andres UL; Merlano Duncan, Juan Carlos UL; Eappen, Geoffrey UL et al

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 ▲]

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See detailLes archevêques de Milan face aux premières expériences seigneuriales: stratégies et positionnements (milieu XIIIe-début XIVe s.)
Salemme, Timothy UL

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

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See detailThe Rallye Platform: Mobile Location-based Serious Games for Digital Cultural Heritage
Botev, Jean UL; Camarda, Sandra UL; Ohlhoff, Claude

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

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See detailAI-based Question Answering Assistance for Analyzing Natural-language Requirements
Ezzini, Saad UL; Abualhaija, Sallam UL; Arora, Chetan UL et al

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 ▲]

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See detailDaMAT: A Data-driven Mutation Analysis Tool
Vigano, Enrico UL; Cornejo Olivares, Oscar Eduardo UL; Pastore, Fabrizio UL et al

in Proceedings of the 45th International Conference on Software Engineering (ICSE ’23) (in press)

We present DaMAT, a tool that implements data- driven mutation analysis. In contrast to traditional code-driven mutation analysis tools it mutates (i.e., modifies) the data ex- changed by components ... [more ▼]

We present DaMAT, a tool that implements data- driven mutation analysis. In contrast to traditional code-driven mutation analysis tools it mutates (i.e., modifies) the data ex- changed by components instead of the source of the software under test. Such an approach helps ensure that test suites appropriately exercise components interoperability — essential for safety-critical cyber-physical systems. A user-provided fault model drives the mutation process. We have successfully evalu- ated DaMAT on software controlling a microsatellite and a set of libraries used in deployed CubeSats. A demo video of DaMAT is available at https://youtu.be/s5M52xWCj84 [less ▲]

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See detailL’exposition d’objets ou de collections de « marque » : cobranding, réécriture, réénonciation
Schall, Céline UL

in Laval, Sylvie (Ed.) Marques muséales : un espace public revisité ? (in press)

Le cobranding est une pratique habituelle du secteur marchand. Mais lorsque deux musées réalisent ensemble une exposition, peut-on parler de cobranding muséal ? Quelles en seraient les spécificités  ... [more ▼]

Le cobranding est une pratique habituelle du secteur marchand. Mais lorsque deux musées réalisent ensemble une exposition, peut-on parler de cobranding muséal ? Quelles en seraient les spécificités ? Quels effets peut avoir cette démarche sur la communication ou sur l’exposition ? Notamment, le musée d’accueil s’approprie-t-il simplement l’imaginaire et les valeurs de la marque invitée par un phénomène de « transfert » ? Pour répondre à ces questions, nous étudions trois expositions qui reprennent des objets ou collections de musées dont la marque est internationalement reconnue. L’analyse sémiotique des images de marque du musée d’accueil et du musée invité ainsi que l’analyse sémiopragmatique des expositions montrent l’impact de la présence d’une grande marque internationale sur l’exposition et réciproquement, l’impact de l’exposition sur l’image de marque du musée d’accueil. Plus qu’un simple cobranding, c’est une réécriture impliquant une réénonciation du discours et des valeurs portés par les marques qui est proposée à travers ces expositions. Le processus aboutit à la création de nouveaux espaces symboliques et d’expositions réflexives, avec plusieurs niveaux de lecture. [less ▲]

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See detailTriangular Intertwined Frequency Selective Surface
Vasquez-Peralvo, Juan Andres UL; Merlano Duncan, Juan Carlos UL; Chatzinotas, Symeon UL et al

in Vasquez-Peralvo, Juan Andres; Merlano Duncan, Juan Carlos; Chatzinotas, Symeon (Eds.) et al International symposium on antennas and propagation (in press)

This paper presents a frequency selective surface design and simulation using intertwined triangular structures. It has been discovered that by using the proposed tessellated intertwined lattice, the ... [more ▼]

This paper presents a frequency selective surface design and simulation using intertwined triangular structures. It has been discovered that by using the proposed tessellated intertwined lattice, the reduction of the resonance frequency of a frequency selective surface can be improved by 22.58% compared with other triangular structures. Additionally, this structure is used as a MEFSS to improve the miniaturization of the structure and obtain a compact, angular stable band-pass filter. The simulations presented in this paper have been obtained using CST Microwave Studio. [less ▲]

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See detailCurves over finite fields and moduli spaces
van der Geer, Gerard UL

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

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See detail« … Eripuit servus mihi vitam » - Représentations médiatiques de la violence et de la criminalité dans les provinces occidentales de l'Empire romain
Binsfeld, Andrea UL

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)

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See detailAdvancing the Meet-in-the-Filter Technique: Applications to CHAM and KATAN
Biryukov, Alexei UL; Teh, Je Sen UL; Udovenko, Aleksei UL

in Smith, Benjamin; Wu, Huapeng (Eds.) Selected Areas in Cryptography (in press)

Recently, Biryukov et al. presented a new technique for key recovery in differential cryptanalysis, called meet-in-the-filter (MiF). In this work, we develop theoretical and practical aspects of the ... [more ▼]

Recently, Biryukov et al. presented a new technique for key recovery in differential cryptanalysis, called meet-in-the-filter (MiF). In this work, we develop theoretical and practical aspects of the technique, which helps understanding and simplifies application. In particular, we show bounds on MiF complexity and conditions when the MiF-enhanced attack may reach them. We present a method based on trail counting which allows to estimate filtering strength of involved rounds and perform consequent complexity analysis with pen and paper, compared to the computer-aided approach of the original work. Furthermore, we show how MiF can be combined with plaintext structures for linear key schedules, allowing to increase the number of attacked rounds or to reduce the data complexity. We illustrate our methods on block cipher families CHAM and KATAN and show best-to-date single-key differential attacks for these ciphers. [less ▲]

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See detailAn (Un)Necessary Evil - Users’ (Un)Certainty about Smartphone App Permissions and Implications for Privacy Engineering
Bongard, Kerstin UL; Sterckx, Jean-Louis; Rossi, Arianna UL et al

in 2022 7th IEEE European Symposium on Security and Privacy Workshops (EuroSPW) (in press)

App permission requests are a control mechanism meant to help users oversee and safeguard access to data and resources on their smartphones. To decide whether to accept or deny such requests and make this ... [more ▼]

App permission requests are a control mechanism meant to help users oversee and safeguard access to data and resources on their smartphones. To decide whether to accept or deny such requests and make this consent valid, users need to understand the underlying reasons and judge the relevance of disclosing data in line with their own use of an app. This study investigates people’s certainty about app permission requests via an online survey with 400 representative participants of the UK population. The results demonstrate that users are uncertain about the necessity of granting app permissions for about half of the tested permission requests. This implies substantial privacy risks, which are discussed in the paper, resulting in a call for user-protecting interventions by privacy engineers. [less ▲]

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See detailA Methodology for Handling Data Movements by Anticipation: Position Paper
Bleuse, Raphaël UL; Lucarelli, Giorgio; Trystram, Denis

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 ▲]

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See detailBlockchain Governance: An Overview and Prediction of Optimal Strategies Using Nash Equilibrium
Khan, Nida UL; Ahmad, Tabrez; Patel, Anass et al

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 ▲]

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See detailVon Objekt- und Meta-Ebenen: Analyse der Softwareanforderungen computergestützter juristischer Entscheidungen
Adrian, Axel; Rapp, Max; Steen, Alexander UL

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 ▲]

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See detailA New Perspective on the Luxembourgish Genitive
Döhmer, Caroline UL

in Germanic Genitives (in press)

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See detailLe quotidien d’un poilu de la première guerre mondiale sur Facebook : nouvelle forme de médiation, nouvelle expérience ?
Schall, Céline UL; Vilatte, Jean-Christophe

in Les mondes de la médiation culturelle (in press)

« En 2013, le Musée de la Grande Guerre du Pays de Meaux et l’agence de communication DDB ont élaboré une page Facebook d’un genre nouveau. Facebook 1914, le quotidien de la première guerre offre une ... [more ▼]

« En 2013, le Musée de la Grande Guerre du Pays de Meaux et l’agence de communication DDB ont élaboré une page Facebook d’un genre nouveau. Facebook 1914, le quotidien de la première guerre offre une forme de médiation a priori inédite pour un musée français. Elle présente l’histoire d’un personnage de fiction, Léon Vivien, qui raconte son quotidien lors de la première guerre mondiale, sur Facebook, comme si ce réseau social avait existé à cette époque. Cette contribution met en évidence certains des effets de sens de la page par une analyse sémiotique du dispositif et une analyse thématique de ses contenus. Nous questionnons ensuite cette « nouvelle » forme de médiation qui se dit « participante » et qui, en réalité, reste assez classique dans son contenu et sous-exploite le potentiel de Facebook. » [less ▲]

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See detailLessons from Investment Treaty Arbitration
Garcia Olmedo, Javier UL

in Haslehner, Werner; Rust, Alexander; Kofler (Eds.) Alternative Dispute Resolution in Taxation (in press)

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See detailConservazione e ricezione dei documenti pontifici in Italia settentrionale: il caso del monastero cistercense di Chiaravalle Milanese (secoli XII-XVI)
Salemme, Timothy UL

in Salemme, Timothy; Renault, Jean-Baptiste (Eds.) Conservation et réception des documents pontificaux par les Ordres religieux (XIe-XVe siècles). Actes du colloque international. Nancy, 12-13 décembre 2013 (in press)

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See detailLe dialogue entre les juges en matière de protection des droits de l'homme
Pelin Raducu, Ioana UL

in Menetrey, Séverine; Hess, Burkhard (Eds.) Les dialogues des juges en Europe (in press)

Dans cet article, nous allons mettre en exergue quelques aspects des arrêts récents provenant de la Cour de justice de l’UE (Akerberg Frasson, Melloni, Kamberaj)qui démontrent l’émergence d’un standard ... [more ▼]

Dans cet article, nous allons mettre en exergue quelques aspects des arrêts récents provenant de la Cour de justice de l’UE (Akerberg Frasson, Melloni, Kamberaj)qui démontrent l’émergence d’un standard propre de l’UE en matière des droits de l’homme. Cette tendance de la C.J.U.E. contredira le prescrit normatif découlant du « dialogue des juges » d’interprétation conforme à la jurisprudence de la C.E.D.H. avant que l’adhésion de l’UE à la Convention E.D.H. ne soit formellement acquise. [less ▲]

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See detailDiscrete-Phase Sequence Design with Stopband and PSL Constraints for Cognitive Radar
Alaeekerahroodi, Mohammad UL; Kumar, Sumit UL; Mysore Rama Rao, Bhavani Shankar UL et al

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 ▲]

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See detailDesigning and managing an online, personalised research writing course for postgraduates
Deroey, Katrien UL; Skipp, Jennifer

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 ▲]

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See detailTowards Log Slicing
Dawes, Joshua UL; Shin, Donghwan; Bianculli, Domenico UL

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 ▲]

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See detailThe Elements of Visual Art Recommendation: Learning Latent Semantic Representations of Paintings
Yilma, Bereket Abera UL; Leiva, Luis A. UL

in Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems (CHI ’23) (2023, April)

Artwork recommendation is challenging because it requires understanding how users interact with highly subjective content, the complexity of the concepts embedded within the artwork, and the emotional and ... [more ▼]

Artwork recommendation is challenging because it requires understanding how users interact with highly subjective content, the complexity of the concepts embedded within the artwork, and the emotional and cognitive reflections they may trigger in users. In this paper, we focus on efficiently capturing the elements (i.e., latent semantic relationships) of visual art for personalized recommendation. We propose and study recommender systems based on textual and visual feature learning techniques, as well as their combinations. We then perform a small-scale and a large-scale user-centric evaluation of the quality of the recommendations. Our results indicate that textual features compare favourably with visual ones, whereas a fusion of both captures the most suitable hidden semantic relationships for artwork recommendation. Ultimately, this paper contributes to our understanding of how to deliver content that suitably matches the user's interests and how they are perceived. [less ▲]

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See detailRefining the Mandatory Cybersecurity Incident Reporting under the NIS Directive 2.0: Event Types and Reporting Processes
Schmitz, Sandra UL

in Onwubiko, Cyril; Rosati, Pierangelo; Rege, Aunshul (Eds.) et al Proceedings of the International Conference on Cybersecurity, Situational Awareness and Social Media (2023, March 08)

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See detailRegional heterogeneity and individual characteristics in the development of a European tax policy: historical insights from Luxembourg
Danescu, Elena UL

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 ▲]

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See detailPerformance Analysis and Benchmarking of a Temperature Downscaling Deep Learning Model
Panner Selvam, Karthick UL; Brorsson, Mats Hakan UL

in 31st Euromicro International Conference on Parallel, Distributed, and Network-Based Processing, Naples, Italy 1-3 March 2023 (2023, March)

We are presenting here a detailed analysis and performance characterization of a statistical temperature downscaling application used in the MAELSTROM EuroHPC project. This application uses a deep ... [more ▼]

We are presenting here a detailed analysis and performance characterization of a statistical temperature downscaling application used in the MAELSTROM EuroHPC project. This application uses a deep learning methodology to convert low-resolution atmospheric temperature states into high-resolution. We have performed in-depth profiling and roofline analysis at different levels (Operators, Training, Distributed Training, Inference) of the downscaling model on different hardware architectures (Nvidia V100 & A100 GPUs). Finally, we compare the training and inference cost of the downscaling model with various cloud providers. Our results identify the model bottlenecks which can be used to enhance the model architecture and determine hardware configuration for efficiently utilizing the HPC. Furthermore, we provide a comprehensive methodology for in-depth profiling and benchmarking of the deep learning models. [less ▲]

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See detailDie Grenzen aufgezeigt:Technische Innovation und räumliche Abstraktion am Beispiel früher Landkarten der Grenzregion zwischen dem Herzogtum Luxemburg und dem Kurfürstentum Trier
Solchenbach, Karl UL

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 ▲]

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See detailNegative Results of Fusing Code and Documentation for Learning to Accurately Identify Sensitive Source and Sink Methods An Application to the Android Framework for Data Leak Detection
Samhi, Jordan UL; Kober, Kober; Kabore, Abdoul Kader UL et al

in 30th IEEE International Conference on Software Analysis, Evolution and Reengineering (2023, March)

Apps on mobile phones manipulate all sorts of data, including sensitive data, leading to privacy related concerns. Recent regulations like the European GDPR provide rules for the processing of personal ... [more ▼]

Apps on mobile phones manipulate all sorts of data, including sensitive data, leading to privacy related concerns. Recent regulations like the European GDPR provide rules for the processing of personal and sensitive data, like that no such data may be leaked without the consent of the user. Researchers have proposed sophisticated approaches to track sensitive data within mobile apps, all of which rely on specific lists of sensitive source and sink methods. The data flow analysis results greatly depend on these lists' quality. Previous approaches either used incomplete hand-written lists and quickly became outdated or relied on machine learning. The latter, however, leads to numerous false positives, as we show. This paper introduces CoDoC that aims to revive the machine-learning approach to precisely identify the privacy-related source and sink API methods. In contrast to previous approaches, CoDoC uses deep learning techniques and combines the source code with the documentation of API methods. Firstly, we propose novel definitions that clarify the concepts of taint analysis, source, and sink methods. Secondly, based on these definitions, we build a new ground truth of Android methods representing sensitive source, sink, and neither methods that will be used to train our classifier. We evaluate CoDoC and show that, on our validation dataset, it achieves a precision, recall, and F1 score of 91%, outperforming the state-of-the-art SuSi. However, similarly to existing tools, we show that in the wild, i.e., with unseen data, CoDoC performs poorly and generates many false-positive results. Our findings suggest that machine-learning models for abstract concepts such as privacy fail in practice despite good lab results. To encourage future research, we release all our artifacts to the community. [less ▲]

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See detailBringing Movement to Digital Tasks at the Office: Designing an Acceptably Active Interface Interaction for Sending Emails
Keller, Philip; van den Heuvel, Roy; Lallemand, Carine UL

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 ▲]

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See detailExploring the Embodied Experience of Walking Meetings through Bodystorming – Implications for Design
Jacob, Melodie; Damen, Ida; Lallemand, Carine UL

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 ▲]

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See detailTerminal-Aware Multi-Connectivity Scheduler for Uplink Multi-Layer Non-Terrestrial Networks
Dazhi, Michael UL; Al-Hraishawi, Hayder UL; Mysore Rama Rao, Bhavani Shankar UL et al

in IEEE Global Communications Conference (Globecom) (2023, January 12)

This paper introduces the concept of multi-connectivity (MC) to the multi-orbit non-terrestrial networks (NTNs), where user terminals can be served by more than one satellite to achieve higher peak ... [more ▼]

This paper introduces the concept of multi-connectivity (MC) to the multi-orbit non-terrestrial networks (NTNs), where user terminals can be served by more than one satellite to achieve higher peak throughput. MC is a technique initially introduced by the 3rd Generation Partnership Project (3GPP) for terrestrial communications in 4G and 5G, it has shown much gain in the terrestrial domain and this paper explores areas where this concept can benefit the satellite domain. MC can increase throughput, but this entails increased power consumption at user terminal for uplink transmissions. The energy efficiency of uplink communications can be improved by designing efficient scheduling schemes, and to this end, we developed a terminal aware multi-connectivity scheduling algorithm. This proposed algorithm uses the available radio resources and propagation information to intelligently define a dynamic resource allocation pattern, that optimally routes traffic so as to maximize uplink data rate while minimizing the energy consumption at the UT. The algorithm operates with the terminal differentiating multi-layer NTN resource scheduling architecture, which has a softwarized dispatcher at the network layer that classifies and differentiates the packets based on terminal type. The performance of the proposed algorithm was compared with round robin and joint carrier schedulers in terms of uplink data rate and energy efficiency. We also provide architectural design of implementable schedulers for multi-orbital satellite networks that can operate with different classes of terminals. [less ▲]

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See detailFederated Learning for Credit Risk Assessment
Lee, Chul Min UL; Delgado Fernandez, Joaquin UL; Potenciano Menci, Sergio UL et al

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 ▲]

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See detailFederated Learning as a Solution for Problems Related to Intergovernmental Data Sharing
Sprenkamp, Kilian; Delgado Fernandez, Joaquin UL; Eckhardt, Sven et al

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

To address global problems, intergovernmental collaboration is needed. Modern solutions to these problems often include data-driven methods like artificial intelligence (AI), which require large amounts ... [more ▼]

To address global problems, intergovernmental collaboration is needed. Modern solutions to these problems often include data-driven methods like artificial intelligence (AI), which require large amounts of data to perform well. However, data sharing between governments is limited. A possible solution is federated learning (FL), a decentralised AI method created to utilise personal information on edge devices. Instead of sharing data, governments can build their own models and just share the model parameters with a centralised server aggregating all parameters, resulting in a superior overall model. By conducting a structured literature review, we show how major intergovernmental data sharing challenges like disincentives, legal and ethical issues as well as technical constraints can be solved through FL. Enhanced AI while maintaining privacy through FL thus allows governments to collaboratively address global problems, which will positively impact governments and citizens. [less ▲]

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See detailVehicle-to-Infrastructure Communication for Real-Time Object Detection in Autonomous Driving
Hawlader, Faisal UL; Robinet, François UL; Frank, Raphaël UL

in 18th Wireless On-demand Network systems and Services Conference (WONS-23) (2023, January)

Environmental perception is a key element of autonomous driving because the information receive from the perception module influences core driving decisions. An outstanding challenge in real-time ... [more ▼]

Environmental perception is a key element of autonomous driving because the information receive from the perception module influences core driving decisions. An outstanding challenge in real-time perception for autonomous driving lies in finding the best trade-off between detection quality and latency. Major constraints on both computation and power have to be taken into account for real-time perception in autonomous vehicles. Larger object detection models tend to produce the best results, but are also slower at runtime. Since the most accurate detectors cannot run in real-time locally, we investigate the possibility of offloading computation to edge and cloud platforms, which are less resource-constrained. We create a synthetic dataset to train an object detection model and evaluate different offloading strategies. Using real hardware and network simulations, we compare different trade-offs between prediction quality and end-to-end delay. Since sending raw frames over the network implies additional transmission delays, we also explore the use of JPEG compression at varying qualities and measure its impact on prediction metrics. We show that models with adequate compression can be run in real-time on the cloud while outperforming local detection performance. [less ▲]

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See detailAstute Approach to Handling Memory Layouts of Regular Data Structures
Šmelko, Adam; Kruliš, Martin; Kratochvil, Miroslav UL et al

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 ▲]

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See detailATM: Black-box Test Case Minimization based on Test Code Similarity and Evolutionary Search
Pan, Rongqi; Ghaleb, Taher; Briand, Lionel UL

in IEEE/ACM International Conference on Software Engineering (2023)

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See detailLa responsabilité civile du fait des lycanthropes
Calcio, Mathilde UL

in Calcio, Mathilde (Ed.) Horreur et Droit (2023)

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See detailStacked-Cascode Current Steering Architecture for Gallium Nitride Variable-Gain LNAs
Gonzalez Rios, Jorge Luis UL; Vazquez, Diego; Moreno, Robson et al

in IEEE 14th Latin American Symposium on Circuits and Systems (LASCAS 2023) (2023)

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See detailSoK: Secure E-Voting with Everlasting Privacy
Haines, Thomas; Mueller, Johannes UL; Mosaheb, Rafieh UL et al

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 ▲]

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See detailBeam Splash Mitigation for NGSO Spectrum Coexistence between Feeder and User Downlink
Lagunas, Eva UL; Perez-Neira, Ana; Grotz, Joel et al

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

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See detailEfficient Hessian-based DNN Optimization via Chain-Rule Approximation
Temperoni, Alessandro UL; Dalle Lucca Tosi, Mauro UL; Theobald, Martin UL

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

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See detailInk and Paper in the Camp. Ego-Documents of Luxembourger Conscripts in the Soviet Captivity
Ganschow, Inna UL

in Janz, Nina; Scuto, Denis (Eds.) The Impact of War Experiences in Europe (2023)

In the paper by Inna Ganschow, the camp experience in the Soviet Union as a result of forced conscription will be treated, specifically in its artistic processing: secretly written diaries and letters by ... [more ▼]

In the paper by Inna Ganschow, the camp experience in the Soviet Union as a result of forced conscription will be treated, specifically in its artistic processing: secretly written diaries and letters by Luxembourg Wehrmacht soldiers. Contemporary historical research today calls them ego documents – private, handwritten texts of a personal nature. The range of texts to be examined in the lecture ranges from the smuggled out notes and letters that their released comrades took with them to Luxembourg, through diaries, speeches and self-made dictionaries to poems, short stories and drawings, some of which were in the camp and some immediately after the return from Tambov and other camps in the Soviet Union. The focus is on the question of dealing with the thesis of the Auschwitz concentration camp survivor Viktor Frankl, psychiatrist and neurologist from Vienna, that the meaning of camp life - logotherapy - can have a self-healing effect and increase the self-healing powers, which increases the chances of survival. [less ▲]

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See detailEfficient Hamiltonian Reduction for Quantum Annealing on SatCom Beam Placement Problem
Dinh, Thinh Q.; Dau, Son Hoang; Lagunas, Eva UL et al

in IEEE International Conference on Communications (ICC), Rome, Italy, May 2023 (2023)

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See detailLEO-to-User Assignment and Resource Allocation for Uplink Transmit Power Minimization
Nguyen, Kha Hung UL; Ha, Vu Nguyen UL; Lagunas, Eva UL et al

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

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See detailGEO Payload Power Minimization: Joint Precoding and Beam Hopping Design
Ha, Vu Nguyen UL; Nguyen, Ti Ti; Lagunas, Eva UL et al

in Proceedings of IEEE Global Communications Conference GLOBECOM 2022 (2022, December 05)

This paper aims to determine linear precoding (LP) vectors, beam hopping (BH), and discrete DVB-S2X transmission rates jointly for the GEO satellite communication systems to minimize the payload power ... [more ▼]

This paper aims to determine linear precoding (LP) vectors, beam hopping (BH), and discrete DVB-S2X transmission rates jointly for the GEO satellite communication systems to minimize the payload power consumption and satisfy ground users’ demands within a time window. Regarding constraint on the maximum number of illuminated beams per time slot, the technical requirement is formulated as a sparse optimization problem in which the hardware-related beam illumination energy is modeled in a sparsity form of the LP vectors. To cope with this problem, the compressed sensing method is employed to transform the sparsity parts into the quadratic form of precoders. Then, an iterative window-based algorithm is developed to update the LP vectors sequentially to an efficient solution. Additionally, two other two-phase frameworks are also proposed for comparison purposes. In the first phase, these methods aim to determine the MODCOD transmission schemes for users to meet their demands by using a heuristic approach or DNN tool. In the second phase, the LP vectors of each time slot will be optimized separately based on the determined MODCOD schemes. [less ▲]

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See detailFaster and Cheaper Energy Demand Forecasting at Scale
Bernier, Fabien UL; Jimenez, Matthieu UL; Cordy, Maxime UL et al

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 ▲]

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See detailJoint Linear Precoding and DFT Beamforming Design for Massive MIMO Satellite Communication
Ha, Vu Nguyen UL; Abdullah, Zaid UL; Eappen, Geoffrey UL et al

in IEEE Global Communications Conference GLOBECOM 2022 (2022, December)

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See detailLearning-Based Joint Channel Prediction and Antenna Selection for Massive MIMO with Partial CSI
He, Ke UL; Vu, Thang Xuan UL; Chatzinotas, Symeon UL et al

in IEEE GLOBECOM 2022 proceedings (2022, December)

This paper investigates the massive multi-input multi-output (MIMO) system in practical deployment scenarios, in which, to balance the economic and energy efficiency with the system performance, the ... [more ▼]

This paper investigates the massive multi-input multi-output (MIMO) system in practical deployment scenarios, in which, to balance the economic and energy efficiency with the system performance, the number of radio frequency (RF) chains is smaller than the number of antennas. The base station employs antenna selection (AS) to fully harness the spatial multiplexing gain. Conventional AS techniques require full channel state information (CSI), which is time-consuming as the antennas cannot be simultaneously connected to the RF chains during the channel estimation process. To tackle this issue, we propose a novel joint channel prediction and AS (JCPAS) framework to reduce the CSI acquisition time and improve the system performance under temporally correlated channels. Our proposed JCPAS framework is a fully probabilistic model driven by deep unsupervised learning. The proposed framework is able to predict the current full CSI, while requiring only a historical window of partial observations. Extensive simulation results show that the proposed JCPAS can significantly improve the system performance under temporally correlated channels, especially for very large-scale systems with highly correlated channels. [less ▲]

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See detailDRIVE-B5G: A Flexible and Scalable Platform Testbed for B5G-V2X Networks
Djaidja, Taki Eddine Toufik; Brik, Bouziane; Boualouache, Abdelwahab UL et al

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 ▲]

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See detailDRIVE-B5G: A Flexible and Scalable Platform Testbed for B5G-V2X Networks
Djaidja, Taki Eddine Toufik; Brik, Bouziane; Boualouache, Abdelwahab UL et al

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 ▲]

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See detailLightweight Permutation-Based Cryptography for the Ultra-Low-Power Internet of Things
Alsahli, Malik; Borgognoni, Alex UL; Cheng, Hao UL et al

in Bella, Giampaolo; Doinea, Mihai; Janicke, Helge (Eds.) Innovative Security Solutions for Information Technology and Communications 15th International Conference, SECITC 2022, Virtual Event, December 8-9, 2022, Revised Selected Papers (2022, December)

The U.S. National Institute of Standards and Technology is currently undertaking a process to evaluate and eventually standardize one or more "lightweight" algorithms for authenticated encryption and ... [more ▼]

The U.S. National Institute of Standards and Technology is currently undertaking a process to evaluate and eventually standardize one or more "lightweight" algorithms for authenticated encryption and hashing that are suitable for resource-restricted devices. In addition to security, this process takes into account the efficiency of the candidate algorithms in various hardware environments (e.g. FPGAs, ASICs) and software platforms (e.g. 8, 16, 32-bit microcontrollers). However, while there exist numerous detailed benchmarking results for 8-bit AVR and 32-bit ARM/RISC-V/ESP32 microcontrollers, relatively little is known about the candidates' efficiency on 16-bit platforms. In order to fill this gap, we present a performance evaluation of the final-round candidates Ascon, Schwaemm, TinyJambu, and Xoodyak on the MSP430 series of ultra-low-power 16-bit microcontrollers from Texas Instruments. All four algorithms were explicitly designed to achieve high performance in software and have further in common that the underlying primitive is a permutation. We discuss how these permutations can be implemented efficiently in Assembly language and analyze how basic design decisions impact their execution time on the MSP430 architecture. Our results show that, overall, Schwaemm is the fastest algorithm across various lengths of data and associated data, respectively. Xoodyak has benefits when a large amount of associated data is to be authenticated, whereas TinyJambu is very efficient for the authentication of short messages. [less ▲]

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See detailXAI: Using Smart Photobooth for Explaining History of Art
Najjar, Amro UL; Hosseini Kivanani, Nina UL; Tchappi Haman, Igor UL et al

in XAI: Using Smart Photobooth for Explaining History of Art (2022, December)

The rise of Artificial Intelligence has led to advancements in daily life, including applications in industries, telemedicine, farming, and smart cities. It is necessary to have human-AI synergies to ... [more ▼]

The rise of Artificial Intelligence has led to advancements in daily life, including applications in industries, telemedicine, farming, and smart cities. It is necessary to have human-AI synergies to guarantee user engagement and provide interactive expert knowledge, despite AI’s success in "less technical" fields. In this article, the possible synergies between humans and AI to explain the development of art history and artistic style transfer are discussed. This study is part of the "Smart Photobooth" project that is able to automatically transform a user’s picture into a well-known artistic style as an interactive approach to introduce the fundamentals of the history of art to the common people and provide them with a concise explanation of the various art painting styles. This study investigates human-AI synergies by combining the explanation produced by an explainable AI mechanism with a human expert’s insights to provide reasons for school students and a larger audience. [less ▲]

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See detailEdge Computing-enabled Intrusion Detection for C-V2X Networks using Federated Learning
Selamnia, Aymene; Brik, Bouziane; Senouci, Sidi-Mohammed et al

in The 2022 IEEE Global Communications Conference (GLOBECOM) (2022, December)

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML ... [more ▼]

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML) techniques. However, it has been shown that generating ML-based models in a centralized way consumes a massive quantity of network resources, such as CPU/memory and bandwidth, which may represent a critical issue in such networks. To avoid this problem, the new concept of Federated Learning (FL) emerged to build ML-based models in a distributed and collaborative way. In such an approach, the set of nodes, e.g., vehicles or gNodeB, collaborate to create a global ML model trained across these multiple decentralized nodes, each one with its respective data samples that are not shared with any other nodes. In this way, FL enables, on the one hand, data privacy since sharing data with a central location is not always feasible and, on the other hand, network overhead reduction. This paper designs a new IDS for C-V2X networks based on FL. It leverages edge computing to not only build a prediction model in a distributed way but also to enable low-latency intrusion detection. Moreover, we build our FL-based IDS on top of the well-known CIC-IDS2018 dataset, which includes the main network attacks. Noting that, we first perform feature engineering on the dataset using the ANOVA method to consider only the most informative features. Simulation results show the efficiency of our system compared to the existing solutions in terms of attack detection accuracy while reducing network resource consumption. [less ▲]

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See detailLes 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
Delhaise, Elise UL

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

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See detailPower Allocation for Space-Terrestrial Cooperation Systems with Statistical CSI
Chien, Trinh-Van; Lagunas, Eva UL; Hoang, Tiep M. et al

in IEEE Global Communications Conference (IEEE Globecom), Rio de Janeiro, Brazil, Dec. 2022 (2022, December)

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See detailCoexistence of eMBB and URLLC in Open Radio Access Networks: A Distributed Learning Framework
Al-Senwi, Madyan Abdullah Othman UL; Lagunas, Eva UL; Chatzinotas, Symeon UL

in IEEE Global Communications Conference (IEEE Globecom), Rio de Janeiro, Brazil, Dec. 2022 (2022, December)

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See detailEdge Computing enabled Intrusion Detection for C-V2X Networks using Federated Learning
Selamnia, Aymene; Brik, Bouziane; Senouci, Sidi-Mohammed et al

in The 2022 IEEE Global Communications Conference (GLOBECOM) (2022, December)

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML ... [more ▼]

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML) techniques. However, it has been shown that generating ML-based models in a centralized way consumes a massive quantity of network resources, such as CPU/memory and bandwidth, which may represent a critical issue in such networks. To avoid this problem, the new concept of Federated Learning (FL) emerged to build ML-based models in a distributed and collaborative way. In such an approach, the set of nodes, e.g., vehicles or gNodeB, collaborate to create a global ML model trained across these multiple decentralized nodes, each one with its respective data samples that are not shared with any other nodes. In this way, FL enables, on the one hand, data privacy since sharing data with a central location is not always feasible and, on the other hand, network overhead reduction. This paper designs a new IDS for C-V2X networks based on FL. It leverages edge computing to not only build a prediction model in a distributed way but also to enable low-latency intrusion detection. Moreover, we build our FL-based IDS on top of the well-known CIC-IDS2018 dataset, which includes the main network attacks. Noting that, we first perform feature engineering on the dataset using the ANOVA method to consider only the most informative features. Simulation results show the efficiency of our system compared to the existing solutions in terms of attack detection accuracy while reducing network resource consumption. [less ▲]

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See detailLost in legal data visualization? A legal scholar’s view on the ECB dedicated section in EUR-Lex
Allemand, Frederic UL

in European Central Bank (Ed.) ESCB Legal Conference 2022 (2022, December)

Legal data visualisation and legal knowledge visualisation are increasingly attracting the attention of the legal community, given their alleged positive impact on legal teaching, access to and ... [more ▼]

Legal data visualisation and legal knowledge visualisation are increasingly attracting the attention of the legal community, given their alleged positive impact on legal teaching, access to and understanding of the law by citizens and/or litigants, or the production of new legal products or services (e.g. Stanford Legal Design Lab). On the other hand, very few legal research studies are based on and integrate into their analysis the visualization of legal data, legal information, or of legal knowledge. Even fewer studies examine the impact of these tools on legal research methodology. Legal scholars are no less skilled and familiar with the use of IT tools, from preparing their lectures (e.g. ppt presentations) to consulting online databases or using expert systems to review articles. Is the lack of interest in legal data visualisation tools an expression of any technological difficulty? To use Friedrich Lachmayer's metaphor, "Legal informatics, which includes the visualisation of legal data, is about building a bridge between law and informatics. But in the design of visualisation tools, informatics scholars expect too much from legal scholars, then the latter give up and the bridge collapses. Or does the problem stem from a specific feature of the law, namely the ontological formalism of legal norms, which would prevent the dissemination of these tools - or render them useless? Rather than exploring this issue from a theoretical perspective, this study will examine the relevance of legal data visualization tools through the analysis of a concrete case, namely the updating that the present author is to carry out of the "Euro" section, published in the French Répertoire Dalloz. This section, originally written in 2002 by Professor Jean-Victor Louis, analyses the monetary law of the Union. In addition to updating the references to the relevant legal acts and instruments in force, this new version should also highlight changes to the content of the lex monetae and related legislation (protection of banknotes and coins, anti-counterfeiting measures, conversion and rounding procedures, etc.). As part of the updating process, the research methodology will be based on the visualisation tools made available by EUR-lex. The study will therefore examine the extent to which these tools have supported the research and facilitated the identification of new insights. Or, on the contrary, to what extent they proved to be inappropriate or insufficient and, if so, for what reasons? [less ▲]

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See detailSecurity Modeling and Analysis of Moving Target Defense in Software Defined Networks
Rodrigues de Mendonça Neto, Júlio UL; Kim, Minjune; Graczyk, Rafal UL et al

in Security Modeling and Analysis of Moving Target Defense in Software Defined Networks (2022, November 28)

The use of traditional defense mechanisms or intrusion detection systems presents a disadvantage for defenders against attackers since these mechanisms are essentially reactive. Moving target defense (MTD ... [more ▼]

The use of traditional defense mechanisms or intrusion detection systems presents a disadvantage for defenders against attackers since these mechanisms are essentially reactive. Moving target defense (MTD) has emerged as a proactive defense mechanism to reduce this disadvantage by randomly and continuously changing the attack surface of a system to confuse attackers. Although significant progress has been made recently in analyzing the security effectiveness of MTD mechanisms, critical gaps still exist, especially in maximizing security levels and estimating network reconfiguration speed for given attack power. In this paper, we propose a set of Petri Net models and use them to perform a comprehensive evaluation regarding key security metrics of Software-Defined Network (SDNs) based systems adopting a time-based MTD mechanism. We evaluate two use-case scenarios considering two different types of attacks to demonstrate the feasibility and applicability of our models. Our analyses showed that a time-based MTD mechanism could reduce the attackers’ speed by at least 78% compared to a system without MTD. Also, in the best-case scenario, it can reduce the attack success probability by about ten times. [less ▲]

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See detailEconomic Ideas and Political Action in Shaping Economic and Monetary Union: Pierre Werner and Luxembourg
Danescu, Elena UL

in Danescu, Elena; Dima, Alina (Eds.) Fostering recovery through metaverse business modelling - An interdisciplinary analysis of the new paradigm shift (2022, November 19)

The international financial centre in Luxembourg grew considerably in the 1960s, driven by proactive government policy, flexible regulation, a willingness to harness external opportunities and the ... [more ▼]

The international financial centre in Luxembourg grew considerably in the 1960s, driven by proactive government policy, flexible regulation, a willingness to harness external opportunities and the establishment of Community institutions and European funding institutions in the country. As Luxembourg was in a currency union with Belgium within the Belgium-Luxembourg Economic Union and did not have its own Central Bank, these developments were all the more meaningful. When the European integration process experienced a series of major crises – including the failure of the European Defence Community and European Political Community in 1954, the empty chair crisis in 1966 and General de Gaulle’s veto on British accession in 1962 and 1967 –, Luxembourg set out on the path of European monetary integration, under the impetus of Finance Minister and Prime Minister Pierre Werner. In October 1970, the Werner Report provided a detailed blueprint for Economic and Monetary Union and laid the foundations for the euro. The Luxembourg financial centre would serve as a “laboratory” for the future single currency. This paper makes extensive use of relevant European and international archives and original interviews, adopting an interdisciplinary approach to analyse Luxembourg’s leading role in reconciling different views on EMU and fostering political commitment to a European currency among the Member States. [less ▲]

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See detailSpecifying Source Code and Signal-based Behaviour of CPS Components
Dawes, Joshua UL; Bianculli, Domenico UL

in Dawes, Joshua; Bianculli, Domenico (Eds.) Proceedings of the 18th International Conference on Formal Aspects of Component Software (2022, November)

Specifying properties over the behaviour of components of Cyber-Physical Systems usually focuses on the behaviour of signals, i.e., the behaviour of the physical part of the system, leaving the behaviour ... [more ▼]

Specifying properties over the behaviour of components of Cyber-Physical Systems usually focuses on the behaviour of signals, i.e., the behaviour of the physical part of the system, leaving the behaviour of the cyber components implicit. There have been some attempts to provide specification languages that enable more explicit reference to the behaviour of cyber components, but it remains awkward to directly express the behaviour of both cyber and physical components in the same specification, using one formalism. In this paper, we introduce a new specification language, Source Code and Signal Logic (SCSL), that 1) provides syntax specific to both signals and events originating in source code; and 2) does not require source code events to be abstracted into signals. We introduce SCSL by giving its syntax and semantics, along with examples. We then provide a comparison between SCSL and existing specification languages, using an example property, to show the benefit of using SCSL to capture certain types of properties. [less ▲]

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See detailRobust Techniques for Building Footprint Extraction in Aerial Laser Scanning 3D Point Clouds
Nurunnabi, Abdul Awal Md UL; Teferle, Felix Norman UL; Balado, Jesus et al

in Robust Techniques for Building Footprint Extraction in Aerial Laser Scanning 3D Point Clouds (2022, November)

The building footprint is crucial for a volumetric 3D representation of a building that is applied in urban planning, 3D city modeling, cadastral and topographic map generation. Aerial laser scanning (ALS ... [more ▼]

The building footprint is crucial for a volumetric 3D representation of a building that is applied in urban planning, 3D city modeling, cadastral and topographic map generation. Aerial laser scanning (ALS) has been recognized as the most suitable means of large-scale 3D point cloud data (PCD) acquisition. PCD can produce geometric detail of a scanned surface. However, it is almost impossible to get point clouds without noise and outliers. Besides, data incompleteness and occlusions are two common phenomena for PCD. Most of the existing methods for building footprint extraction employ classification, segmentation, voting techniques (e.g., Hough-Transform or RANSAC), or Principal Component Analysis (PCA) based methods. It is known that classical PCA is highly sensitive to outliers, even RANSAC which is known as a robust technique for shape detection is not free from outlier effects. This paper presents a novel algorithm that employs MCMD (maximum consistency within minimum distance), MSAC (a robust variant of RANSAC) and a robust regression to extract reliable building footprints in the presence of outliers, missing points and irregular data distributions. The algorithm is successfully demonstrated through two sets of ALS PCD. [less ▲]

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See detailDISCOV: Stimulating Physical Activity through an Explorative Interactive Walking Experience
van Renswouw, Loes; Verhoef, Jasmijn; Vos, Steven et al

in [ ] With Design: Reinventing Design Modes (2022, November)

Aware of the consequences of their inactive lifestyles, many people still struggle to integrate enough physical activity into their busy lives. Interventions that nudge to reinforce existing active ... [more ▼]

Aware of the consequences of their inactive lifestyles, many people still struggle to integrate enough physical activity into their busy lives. Interventions that nudge to reinforce existing active behavior seem therefore more likely to be effective than those adding an activity to daily routines. To encourage people to increase their physical activity level, we designed Discov, a network of physical waypoints triggering people to lengthen their walks. Placed in a public park, Discov encourages people to explore their surroundings in a fun and challenging way by creating an interactive walking experience. Adopting a Research-through-Design approach, we explore the potential of the design of accessible infrastructures and human-environment interactions to impact public health by nudging citizens into being more physically active. We discuss insights gathered through this process and report on first user tests of this interactive walking experience. [less ▲]

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See detailUX Needs Cards – A Pragmatic Tool to Support Experience Design Through Psychological Needs
Lallemand, Carine UL

in [ ] With Design: Reinventing Design Modes (2022, November)

The psychological needs-driven UX approach is a well-explored area in UX research and a powerful framework for the design of optimal experiences with systems and products. However, the transfer from ... [more ▼]

The psychological needs-driven UX approach is a well-explored area in UX research and a powerful framework for the design of optimal experiences with systems and products. However, the transfer from research to practice is slow and this approach is not yet widely used by practitioners. As card- based methods have been shown to support designers in both the generation of ideas and the evaluation of their designs, we created the UX needs cards as a pragmatic tool able to support a needs-driven UX process. We present the iterative development of the card-set and its associated techniques and report on three use cases, demonstrating the effectiveness of this tool for user research, idea generation and UX evaluation. Our empirical findings suggest that the UX needs cards are a valuable tool able to support design practice, being easily understood by lay users and a source of inspiration for designers. Acting as a tangible translation of a research framework, the UX needs cards promote theory-driven design strategies and provide researchers, designers, and educators with a tool to clearly communicate the framework of psychological needs. [less ▲]

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See detailAsynja: Sensorial Design for Running Motivation
Menheere, Daphne; Hilderink, Myrthe; Vos, Steven et al

in [ ] With Design: Reinventing Design Modes (2022, November)

If starting to run is an easy decision, committing to a long-term running routine proves to be a more challenging endeavor for many people. In this pictorial, we unravel the design process of Asynja, an ... [more ▼]

If starting to run is an easy decision, committing to a long-term running routine proves to be a more challenging endeavor for many people. In this pictorial, we unravel the design process of Asynja, an artefact that triggers exercise imagery by using natural scents related to running. Relying on peripheral interaction, this research probe subtly nudges users to go running, thereby supporting them to transform their positive intentions into actions. Exploring sensoriality as a design opportunity for behavior change interventions, we invite the community to expand the design space of exercise-related motivational products and systems. [less ▲]

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See detailLearning to Grasp on the Moon from 3D Octree Observations with Deep Reinforcement Learning
Orsula, Andrej UL; Bøgh, Simon; Olivares Mendez, Miguel Angel UL et al

in Proceedings of 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) (2022, October 23)

Extraterrestrial rovers with a general-purpose robotic arm have many potential applications in lunar and planetary exploration. Introducing autonomy into such systems is desirable for increasing the time ... [more ▼]

Extraterrestrial rovers with a general-purpose robotic arm have many potential applications in lunar and planetary exploration. Introducing autonomy into such systems is desirable for increasing the time that rovers can spend gathering scientific data and collecting samples. This work investigates the applicability of deep reinforcement learning for vision-based robotic grasping of objects on the Moon. A novel simulation environment with procedurally-generated datasets is created to train agents under challenging conditions in unstructured scenes with uneven terrain and harsh illumination. A model-free off-policy actor-critic algorithm is then employed for end-to-end learning of a policy that directly maps compact octree observations to continuous actions in Cartesian space. Experimental evaluation indicates that 3D data representations enable more effective learning of manipulation skills when compared to traditionally used image-based observations. Domain randomization improves the generalization of learned policies to novel scenes with previously unseen objects and different illumination conditions. To this end, we demonstrate zero-shot sim-to-real transfer by evaluating trained agents on a real robot in a Moon-analogue facility. [less ▲]

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See detailHybrid Beamforming Design for OFDM Dual-Function Radar-Communication System with Double-Phase-Shifter Structure
Wang, Bowen; Cheng, Ziyang; Wu, Linlong UL et al

in 2022 30th European Signal Processing Conference (EUSIPCO) (2022, October 18)

In this paper, the problem of the hybrid beamforming (HBF) for a millimeter wave (mmWave) orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system in the presence ... [more ▼]

In this paper, the problem of the hybrid beamforming (HBF) for a millimeter wave (mmWave) orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system in the presence of signal-dependent interference is studied. The HBF network is based on the subarray connection architecture combining with the double-phase-shifter (DPS) structure. To achieve the dual functionality, we formulate the problem by maximizing the communication spectral efficiency subject to the constraints of radar integrated side-lobe to main-lobe ratio (ISMR), space-frequency nulling (SFN) and energy. An efficient algorithm based on the consensus alternating direction method of multipliers (CADMM) frame-work is developed to tackle the resultant nonconvex problem. Simulation results demonstrate the superiority of the proposed DPS structure and HBF algorithm. [less ▲]

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See detailDistributed 5G NR-based integrated sensing and communication systems: Frame structure and performance analysis
Shi, Shengnan; Cheng, Ziyang; Wu, Linlong UL et al

in 2022 30th European Signal Processing Conference (EUSIPCO) (2022, October 18)

This paper discusses a distributed Integrated Sensing and Communication (ISAC) network based on 5G NR. Each BS in the cellular network adopts half-duplex operation, and every three adjacent BSs construct ... [more ▼]

This paper discusses a distributed Integrated Sensing and Communication (ISAC) network based on 5G NR. Each BS in the cellular network adopts half-duplex operation, and every three adjacent BSs construct a cooperative sensing system. Based on the 5G NR standard frame configuration, we develop a new procedure and protocol to support the proposed ISAC network. Under this network, we analyze the performance of both sensing and communication in practical scenarios. Simulations show the effectiveness of the proposed ISAC network. [less ▲]

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See detailAutomatic Repair and Deadlock Detection for Parameterized Systems
Jacobs, Swen; Sakr, Mouhammad UL; Volp, Marcus UL

in Automatic Repair and Deadlock Detection for Parameterized Systems (2022, October 15)

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See detailAgile Systems Engineering for sub-CubeSat scale spacecraft
Kanavouras, Konstantinos UL; Hein, Andreas UL; Sachidanand, Maanasa UL

in Proceedings of the International Astronautical Congress, IAC22 (2022, October 14)

Space systems miniaturization has been increasingly popular for the past decades, with over 1600 CubeSats and 300 sub-CubeSat sized spacecraft estimated to have been launched since 1998. This trend ... [more ▼]

Space systems miniaturization has been increasingly popular for the past decades, with over 1600 CubeSats and 300 sub-CubeSat sized spacecraft estimated to have been launched since 1998. This trend towards decreasing size enables the execution of unprecedented missions in terms of quantity, cost and development time, allowing for massively distributed satellite networks, and rapid prototyping of space equipment. Pocket-sized spacecraft can be designed in-house in less than a year and can reach weights of less than 10g, reducing the considerable effort typically associated with orbital flight. However, while Systems Engineering methodologies have been proposed for missions down to CubeSat size, there is still a gap regarding design approaches for picosatellites and smaller spacecraft, which can exploit their potential for iterative and accelerated development. In this paper, we propose a Systems Engineering methodology that abstains from the classic waterfall-like approach in favor of agile practices, focusing on available capabilities, delivery of features and design "sprints". Our method, originating from the software engineering disciplines, allows quick adaptation to imposed constraints, changes to requirements and unexpected events (e.g. chip shortages or delays), by making the design flexible to well-defined modifications. Two femtosatellite missions, currently under development and due to be launched in 2023, are used as case studies for our approach, showing how miniature spacecraft can be designed, developed and qualified from scratch in 6 months or less. We claim that the proposed method can simultaneously increase confidence in the design and decrease turnaround time for extremely small satellites, allowing unprecedented missions to take shape without the overhead traditionally associated with sending cutting-edge hardware to space. [less ▲]

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See detailPerformance Modeling of Weather Forecast Machine Learning for Efficient HPC
Panner Selvam, Karthick UL; Brorsson, Mats Hakan UL

in International Conference on Distributed Computing Systems (ICDCS), Italy 10-13 July 2022 (2022, October 13)

High-performance computing is a prime area for many applications. Majorly, weather and climate forecast applications use the HPC system because it needs to give a good result with low latency. In recent ... [more ▼]

High-performance computing is a prime area for many applications. Majorly, weather and climate forecast applications use the HPC system because it needs to give a good result with low latency. In recent years machine learning and deep learning models have been widely used to forecast the weather. However, to the best of the author’s knowledge, many applications do not effectively utilise the HPC system for training, testing, validation, and inference of weather data. Our experiment is to conduct performance modeling and benchmark analysis of weather and climate forecast machine learning models and determine the characteristics between the application, model and the underlying HPC system. Our results will help the researchers improvise and optimise the weather forecast system and use the HPC system efficiently. [less ▲]

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See detailEugenia, incarnée par Marina Hands, dans Actrice de Pascal Rambert : le corps d’une mourante comme figuration de la Dame Blanche
Deregnoncourt, Marine UL

in Laforêt, Carole; Raimbault, Nicole (Eds.) Les femmes et leur corps (2022, October 10)

Soit cette description physique de l’actrice franco-britannique Marina Hands par Éric Ruf (Administrateur Général de la Comédie-Française depuis 2014) : Marina est une jeune femme très belle, mais elle a ... [more ▼]

Soit cette description physique de l’actrice franco-britannique Marina Hands par Éric Ruf (Administrateur Général de la Comédie-Française depuis 2014) : Marina est une jeune femme très belle, mais elle a une beauté très singulière. Elle ne correspond en rien au canon. Elle a des épaules des nageuses est-allemandes, elle a des bras longs comme des kilomètres, elle est massive, elle a une drôle de tronche avec des pommettes extrêmement saillantes. Elle n’a pas une beauté classique. Nous avons conclu ainsi notre exposé au 10ème colloque orléanais consacré aux sorcières. En vue de contribuer humblement et d’apporter modestement notre pierre à l’édifice du prochain congrès intitulé : « Femmes des lumières et de l'ombre. Les Femmes et leur Corps », nous entendons, par le biais de cette nouvelle communication, prolonger notre réflexion initiale sur Marina Hands en nous axant plus particulièrement, cette fois-ci, sur le corps de cette comédienne au miroir de son interprétation d’Eugenia dans Actrice de Pascal Rambert. Tout d’abord, en quoi le corps de Marina Hands peut-il être défini comme « masculin » et quels en sont, non seulement, les enjeux, mais aussi, les implications sur son jeu d’actrice ? C’est précisément ce que nous entendons aborder, par la suite, avec le rôle d’Eugenia, protagoniste autour de laquelle se construit l’action d’Actrice de Pascal Rambert. Pourquoi le corps d’Eugenia, mourante, peut-il être perçu comme une figuration de la Dame Blanche, messagère de la mort, et comment Pascal Rambert, renforce-t-il cette idée en construisant un requiem, par un dispositif scénographique singulier ? C’est spécifiquement à ces trois questions centrales auxquelles cette présentation souhaite répondre [less ▲]

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See detail5G-NTN GEO-based Over-The-Air Demonstrator using OpenAirInterface
Kumar, Sumit UL; Kodheli, Oltjon UL; Abdalla, Abdelrahman UL et al

in 5G-NTN GEO-based Over-The-Air Demonstrator using OpenAirInterface (2022, October)

5G services combined with the satellites, also termed 5G NonTerrestrial Networks (5G-NTN), have the capability of providing connectivity to the areas which were previously either unreachable or too costly ... [more ▼]

5G services combined with the satellites, also termed 5G NonTerrestrial Networks (5G-NTN), have the capability of providing connectivity to the areas which were previously either unreachable or too costly to be reached by terrestrial communication networks. Proof-of-Concept (POC) demonstrators, preferably based on open-source implementation are desirable to expedite the ongoing research on 5G-NTN. In this work, we discuss the contributions made during the project 5G-GOA: 5G-Enabled Ground Segment Technologies Over-The-Air Demonstrator which aims to provide direct access to 5G services to a UE through a transparent payload Geostationary (GEO) satellite. 5G-GOA uses the open-source Software-Defined-Radio (SDR) platform OpenAirInterface (OAI) and does the necessary adaptations to achieve its objectives. Adaptations span physical layer techniques (e.g. synchronization) up to upper layer implementations (e.g., timers and random-access procedures) of the Radio Access Network (RAN). The adaptations are based on 3GPP 5G-NTN discussions and the solutions are compliant with the recently frozen 3GPP Release-17. An endto-end SDR-based 5G-NTN demonstrator has been developed for Over-The-Satellite (OTS) testing. We present results from several experiments that were conducted for in-lab validation of the demonstrator using a satellite channel emulator before going live with OTS tests. Experimental results indicate the readiness of the demonstrator for OTS testing which is scheduled during ICSSC 2022. The source code has been submitted to OAI public repository and is available for testing. [less ▲]

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See detailkCV-B: Bootstrap with Cross-Validation for Deep Learning Model Development, Assessment and Selection
Nurunnabi, Abdul Awal Md UL; Teferle, Felix Norman UL; Laefer, Debra et al

in kCV-B: Bootstrap with Cross-Validation for Deep Learning Model Development, Assessment and Selection (2022, October)

This study investigates the inability of two popular data splitting techniques: train/test split and k-fold cross-validation that are to create training and validation data sets, and to achieve sufficient ... [more ▼]

This study investigates the inability of two popular data splitting techniques: train/test split and k-fold cross-validation that are to create training and validation data sets, and to achieve sufficient generality for supervised deep learning (DL) methods. This failure is mainly caused by their limited ability of new data creation. In response, the bootstrap is a computer based statistical resampling method that has been used efficiently for estimating the distribution of a sample estimator and to assess a model without having knowledge about the population. This paper couples cross-validation and bootstrap to have their respective advantages in view of data generation strategy and to achieve better generalization of a DL model. This paper contributes by: (i) developing an algorithm for better selection of training and validation data sets, (ii) exploring the potential of bootstrap for drawing statistical inference on the necessary performance metrics (e.g., mean square error), and (iii) introducing a method that can assess and improve the efficiency of a DL model. The proposed method is applied for semantic segmentation and is demonstrated via a DL based classification algorithm, PointNet, through aerial laser scanning point cloud data. [less ▲]

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See detailThe EU's Digital Identity Policy: Tracing Policy Punctuations
Weigl, Linda UL; Amard, Alexandre UL; Fridgen, Gilbert UL et al

in Proceedings of the 15th International Conference on Theory and Practice of Electronic Governance (ICEGOV) (2022, October)

This paper analyzes the development of the European Union’s digital identity policy. The analysis focuses on the dynamics leading to a sudden shift from identity management as a sensitive topic under ... [more ▼]

This paper analyzes the development of the European Union’s digital identity policy. The analysis focuses on the dynamics leading to a sudden shift from identity management as a sensitive topic under national competence towards a common, harmonized, user-centric European Digital Identity Framework layering on top of Member States’ existing systems. We adopted a syncretic approach to Punctuated Equilibrium Theory and focused specifically on the concept of policy punctuations and policy image. Process tracing is used as a method to trace and interpret causal mechanisms of policy processes. The empirical analysis is grounded in elite interviews and policy documentation. To open up the black box of policy-making, we analyze and disaggregate the policy process. We thereby provide a better understanding of the historical-political and technological mechanisms that determine particular policy outcomes. [less ▲]

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See detailFlash, who? On the Obsolescence of Digital Technology and Its Impact on E-learning Applications: A Case Study.
Grevisse, Christian UL

in Proceedings of the XVII Latin American Conference on Learning Technologies (LACLO) (2022, October)

Technology Enhanced Learning has seen a number of technologies during its history, from instructional video cassettes to smartphones and virtual reality environments. Inevitably, with technologies getting ... [more ▼]

Technology Enhanced Learning has seen a number of technologies during its history, from instructional video cassettes to smartphones and virtual reality environments. Inevitably, with technologies getting obsolete due to replacement or lack of support, TEL solutions face the issue of becoming non-functional. In addition, limited resources may force faculties to abandon certain solutions instead of recreating them with newer technologies. In this paper, we present a case study of an animal neurophysiology virtual lab that has recently suffered from the technology obsolescence phenomenon, both at software and hardware levels. Most importantly, the end of life of Flash was threatening the continuity of an e-learning course. We analyze the issues they were facing, establish a list of requirements for a possible solution and present the implemented changes. We finally perform a risk analysis of obsolescence for the technologies used in the new version of the virtual lab. [less ▲]

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See detailTransition Pathways towards Design Principles of Self-Sovereign Identity
Sedlmeir, Johannes; Huber, Jasmin; Barbereau, Tom Josua UL et al

in Proceedings of the 43rd International Conference on Information Systems (ICIS) (2022, October)

Society’s accelerating digital transformation during the COVID-19 pandemic highlighted clearly that the Internet lacks a secure, efficient, and privacy-oriented model for identity. Self-sovereign identity ... [more ▼]

Society’s accelerating digital transformation during the COVID-19 pandemic highlighted clearly that the Internet lacks a secure, efficient, and privacy-oriented model for identity. Self-sovereign identity (SSI) aims to address core weaknesses of siloed and federated approaches to digital identity management from both users’ and service providers’ perspectives. SSI emerged as a niche concept in libertarian communities, and was initially strongly associated with blockchain technology. Later, when businesses and governments began to invest, it quickly evolved towards a mainstream concept. To investigate this evolution and its effects on SSI, we conduct design science research rooted in the theory of technological transition pathways. Our study identifies nine core design principles of SSI as deployed in relevant applications, and discusses associated competing political and socio-technical forces in this space. Our results shed light on SSI’s key characteristics, its development pathway, and tensions in the transition between regimes of digital identity management. [less ▲]

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See detailTowards the Application of Neuromorphic Computing to Satellite Communications
Ortiz Gomez, Flor de Guadalupe UL; Lagunas, Eva UL; Alves Martins, Wallace UL et al

in Towards the Application of Neuromorphic Computing to Satellite Communications (2022, October)

Artificial intelligence (AI) has recently received significant attention as a key enabler for future 5G-and-beyond terrestrial wireless networks. The applications of AI to satellite communications is also ... [more ▼]

Artificial intelligence (AI) has recently received significant attention as a key enabler for future 5G-and-beyond terrestrial wireless networks. The applications of AI to satellite communications is also gaining momentum to realize a more autonomous operation with reduced requirements in terms of human intervention. The adoption of AI for satellite communications will set new requirements on computing processors, which will need to support large workloads as efficiently as possible under harsh environmental conditions. In this context, neuromorphic processing (NP) is emerging as a bio-inspired solution to address pattern recognition tasks involving multiple, possibly unstructured, temporal signals and/or requiring continual learning. The key merits of the technology are energy efficiency and capacity for on-device adaptation. In this paper, we highlight potential use cases and applications of NP to satellite communications. We also explore major technical challenges for the implementation of space-based NP focusing on the available NP chipsets. [less ▲]

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See detailPEELER: Learning to Effectively Predict Flakiness without Running Tests
Qin, Yihao; Wang, Shangwen; Liu, Kui et al

in Proceedings of the 38th IEEE International Conference on Software Maintenance and Evolution (2022, October)

—Regression testing is a widely adopted approach to expose change-induced bugs as well as to verify the correctness/robustness of code in modern software development settings. Unfortunately, the ... [more ▼]

—Regression testing is a widely adopted approach to expose change-induced bugs as well as to verify the correctness/robustness of code in modern software development settings. Unfortunately, the occurrence of flaky tests leads to a significant increase in the cost of regression testing and eventually reduces the productivity of developers (i.e., their ability to find and fix real problems). State-of-the-art approaches leverage dynamic test information obtained through expensive re-execution of test cases to effectively identify flaky tests. Towards accounting for scalability constraints, some recent approaches have built on static test case features, but fall short on effectiveness. In this paper, we introduce PEELER, a new fully static approach for predicting flaky tests through exploring a representation of test cases based on the data dependency relations. The predictor is then trained as a neural network based model, which achieves at the same time scalability (because it does not require any test execution), effectiveness (because it exploits relevant test dependency features), and practicality (because it can be applied in the wild to find new flaky tests). Experimental validation on 17,532 test cases from 21 Java projects shows that PEELER outperforms the state-of-the-art FlakeFlagger by around 20 percentage points: we catch 22% more flaky tests while yielding 51% less false positives. Finally, in a live study with projects in-the-wild, we reported to developers 21 flakiness cases, among which 12 have already been confirmed by developers as being indeed flaky. [less ▲]

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See detailNanosensor Location in the Human Circulatory System Based on Electric Circuit Representation of Vessels
Gómez, Jorge Torres; Gonzalez Rios, Jorge Luis UL; Dressler, Falko

in Proceedings of the 9th ACM International Conference on Nanoscale Computing and Communication (2022, October)

Nanotechnologies are advancing precision medicine applications, enhancing the detection and treatment of diseases. Traveling through the human vessels, nanosensors are envisioned to locally detect and ... [more ▼]

Nanotechnologies are advancing precision medicine applications, enhancing the detection and treatment of diseases. Traveling through the human vessels, nanosensors are envisioned to locally detect and actuate on targets very efficiently. In this area, modeling the behavior of traveling nanosensors in the human circulatory system helps developing new mechanisms for medical treatments. This paper explores the accurate modeling of the concentration level of the flowing nanosensors in vessels. We use a Markov chain formulation to predict the stationary distribution of them in the variety of vessel segments. To evaluate the transition probabilities of the Markov chain, we compute the blood flow based on the representation of vessels through electric circuit components. The resulting study reveals the dynamics of the movement of nanosensors in the blood flow yielding further details on their concentration level along vessels. [less ▲]

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See detailThe Role of Cultural Fit in the Adoption of Fashionable IT: A Blockchain Case Study
Roth, Tamara UL; Rieger, Alexander UL; Utz, Manuel et al

in Forty-Third International Conference on Information Systems (2022, October)

Investments in fashionable IT do not make organizations more successful than investments in less fashionable alternatives. Many organizations nevertheless associate with fashionable IT to signal ... [more ▼]

Investments in fashionable IT do not make organizations more successful than investments in less fashionable alternatives. Many organizations nevertheless associate with fashionable IT to signal compliance with norms of progress and rationality. These decisions can be risky as fashionable IT is often surrounded by wishful and unbalanced discourse, especially in the ‘fashion up-swing’. Engagement with fashionable IT thus requires the ability to navigate hype narratives and fit the new technology into the adopting organization. Fit needs to be established in many regards, such as political and technological. In this paper, we explore a third and so far, understudied perspective: cultural fit between the values attributed to the fashionable IT through the fashion discourse and those of the recipient organizational context. Through an inductive case study of two blockchain projects, we find that cultural fit can equally be an important determinant for successful adoption of fashionable IT. Moreover, we develop a process theory for how cultural fit can be established through a process of cultural sensemaking and dissonance reduction along two recursive pathways. Adopting organizations can change their implementation of fashionable IT systems and re-frame the narratives surrounding them to fit their organization’s cultural values. Alternatively, they can transform their local or overarching organizational culture by integrating values attributed to the fashionable IT. Overall, we contribute a much-needed organizational culture perspective to IT fashions and extend the discussions on IT cultural conflict. [less ▲]

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See detailPost-quantum Plaintext-awareness
Ebrahimi, Ehsan UL; van Wier, Jeroen UL

in Post-quantum Plaintext-awareness (2022, September 28)

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See detailAndroid Malware Detection Using BERT
Souani, Badr UL; Khanfir, Ahmed UL; Bartel, Alexandre UL et al

in Jianying, Zhou (Ed.) Applied Cryptography and Network Security Workshops (2022, September 24)

In this paper, we propose two empirical studies to (1) detect Android malware and (2) classify Android malware into families. We rst (1) reproduce the results of MalBERT using BERT models learning with ... [more ▼]

In this paper, we propose two empirical studies to (1) detect Android malware and (2) classify Android malware into families. We rst (1) reproduce the results of MalBERT using BERT models learning with Android application's manifests obtained from 265k applications (vs. 22k for MalBERT) from the AndroZoo dataset in order to detect malware. The results of the MalBERT paper are excellent and hard to believe as a manifest only roughly represents an application, we therefore try to answer the following questions in this paper. Are the experiments from MalBERT reproducible? How important are Permissions for mal- ware detection? Is it possible to keep or improve the results by reducing the size of the manifests? We then (2) investigate if BERT can be used to classify Android malware into families. The results show that BERT can successfully di erentiate malware/goodware with 97% accuracy. Further- more BERT can classify malware families with 93% accuracy. We also demonstrate that Android permissions are not what allows BERT to successfully classify and even that it does not actually need it. [less ▲]

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See detailMethods for increasing the dependability of High-performance, Many-core, System-on-Chips
Graczyk, Rafal UL; Memon, Md Saad UL; Volp, Marcus UL

in Graczyk, Rafal; Memon, Md Saad; Volp, Marcus (Eds.) IAC 2022 congress proceedings, 73rd International Astronautical Congress (IAC) (2022, September 21)

Future space exploration and exploitation missions will require significantly increased autonomy of operation for mission planning, decision-making, and adaptive control techniques. Spacecrafts will ... [more ▼]

Future space exploration and exploitation missions will require significantly increased autonomy of operation for mission planning, decision-making, and adaptive control techniques. Spacecrafts will integrate new processing and compression algorithms that are often augmented with machine learning and artificial intelligence capabilities. This functionality will have to be provided with high levels of robustness, reliability, and dependability for conducting missions successfully. High-reliability requirements for space-grade processors have led to trade-offs in terms of costs, energy efficiency, and performance to obtain robustness. However, while high-performance / low-robustness configurations are acceptable in the Earth's vicinity, where assets remain protected by the planet's magnetosphere, they cease to work in more demanding environments, like cis-lunar or deep space, where high-energy particles will affect modern components heavily, causing temporary or permanent damage and ultimately system failures. The above has led to a situation where state-of-the-art processing elements (processors, co-processors, memories, special purpose accelerators, and field-programmable-gate arrays (FPGAs), all possibly integrated into System-on-a-Chip (SoC) designs) are superior to their high reliability, space-qualified counterparts in terms of processing power or energy efficiency. For example, from modern, state-of-the-art (SOTA) devices, one can expect a 2-3 order-of-magnitude performance per Watts improvement over space-grade equipment. Likewise, one finds a gap of approximately nine technology nodes between devices, which translates into a factor 25 decrease in operations per Watts. In this paper, we demonstrate how to utilize part of this enormous performance advantage to increase the robustness and resilience of otherwise susceptible semiconductor devices while harnessing the remaining processing power to build affordable space systems capable of hosting the compute-intensive functionality that future space missions require. We are bridging this performance-reliability gap by researching the enabling building blocks for constructing reliable and secure, space-ready Systems-on-a-Chip from SOTA processing elements. [less ▲]

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See detailInstitutional determinants of intersectional inequalities in science
Kozlowski, Diego UL; Larivière, Vincent; Sugimoto, Cassidy R. et al

in BRIDGES BETWEEN DISCIPLINES: GENDER IN STEM AND SOCIAL SCIENCES (2022, September 12)

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See detailCurrent Status of Bottom-Up Fabrication Approaches for Cu(In,Ga)Se2 Micro-Concentrator Solar Cells
Pérez-Rodríguez, Ana; Goncalinho Poeira, Ricardo Jorge UL; Alves, Marina et al

in 17TH INTERNATIONAL CONFERENCE ON CONCENTRATOR PHOTOVOLTAIC SYSTEMS (CPV-17) (2022, September 02)

Cu(In,Ga)Se2 solar cells have reached a record efficiency of 23.35% and are established as a renewable energy technology. However, future large-scale fabrication might be hindered by the availability and ... [more ▼]

Cu(In,Ga)Se2 solar cells have reached a record efficiency of 23.35% and are established as a renewable energy technology. However, future large-scale fabrication might be hindered by the availability and high cost of raw materials. To reduce the amount of solar cell material, strong efforts have been devoted to the development of the micro-concentrator photovoltaics concept for Cu(In,Ga)Se2 thin film solar cells, which combines the well established concentrator photovoltaics (CPV) technology with the miniaturization of the solar cells. In this work, we review different bottom-up approaches for the fabrication of Cu(In,Ga)Se2 micro solar cells, that potentially allow the reduction of raw material, and we present the latest results on a magnetron sputtering based method for Cu(In,Ga)Se2 micro solar cells. [less ▲]

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See detailThe impact of total cost of ownership on MaaS system appeal using an agent-based approach
Cisterna, Carolina UL; Viti, Francesco UL; Bigi, Federico UL

in The impact of total cost of ownership on MaaS system appeal using an agent-based approach (2022, September)

Despite the interest in the MaaS system is growing fast within the scientific community, it remains uncertain if MaaS could be a potential tool able to reduce car ownership. This study aims to capture the ... [more ▼]

Despite the interest in the MaaS system is growing fast within the scientific community, it remains uncertain if MaaS could be a potential tool able to reduce car ownership. This study aims to capture the impact of the total cost of ownership (TCO) on MaaS demand by endogenizing the MaaS choice and the TCO within the users’ travel choice in an agent-based model. We simulate different TCO price range starting from a benchmark cost in the literature and embed a specific type of MaaS plan which gives unlimited access to the services. Results show a significant growth of MaaS demand when TCO rises, in particular MaaS members are car users who shift their mode choice to public transport by travelling within more trips but in a shorter time slot. In contrast, MaaS users employ public transport for short trips while they still employ cars reducing their travel time but employing the same number of trips when TCO decreases. Results suggest that MaaS might become a more sustainable service by developing specific subsidies to discourage car ownership and by increasing mobility accessibility. [less ▲]

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See detailReinforcement Learning for Attitude Control of a Spacecraft with Flexible Appendages
Mahfouz, Ahmed UL; Valiullin, Ayrat; Lukashevichus, Alexey et al

in IAC 2022 congress proceedings, 73rd International Astronautical Congress (IAC) (2022, September)

This study explores the reinforcement learning (RL) approach to constructing attitude control strategies for a LEOsatellite with flexible appendages. Attitude control system actuated by a set of three ... [more ▼]

This study explores the reinforcement learning (RL) approach to constructing attitude control strategies for a LEOsatellite with flexible appendages. Attitude control system actuated by a set of three reaction wheels is considered.The satellite is assumed to move in a circular low Earth orbit under the action of gravity-gradient torque, randomdisturbance torque, and oscillations excited in flexible appendages. The control policy for rest-to-rest slew maneuversis learned via the Proximal Policy Optimization (PPO) technique. The robustness of the obtained control policy isanalyzed and compared to that of conventional controllers. The first part of the study is focused on problem formulationin terms of Markov Decision Processes, analysis of different reward-shaping techniques, and finally training the RL-agent and comparing the obtained results with the state-of-the-art RL-controllers as well as with the performance ofa commonly used quaternion feedback regulator (Lyapunov-based PD controller). We then proceed to consider thesame spacecraft with flexible appendages added to its structure. Equations of excitable oscillations are appended tothe system and coupling terms are added describing the interactions between the main rigid body and the flexiblestructures. The dynamics of the rigid spacecraft thus becomes coupled with that of its flexible appendages and thecontrol strategy should change accordingly in order to prevent actions that entail excitation of oscillation modes.Again PPO is used to learn the control policy for rest-to-rest slew maneuvers in the extended system. All in all,the proposed reinforcement learning strategy is shown to converge to a policy that matches the performance of thequaternion feedback regulator for a rigid spacecraft. It is also shown that a policy can be trained to take into accountthe highly nonlinear dynamics caused by the presence of flexible elements that need to be brought to rest in the requiredattitude. We also discuss the advantages of the reinforcement learning approach such as robustness and ability of onlinelearning pertaining to the systems that require a high level of autonomy [less ▲]

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See detailIndicators for assessing the necessity of power system flexibility: a systematic review and literature meta-analysis
Bhuiyan, Rajon UL; Weissflog, Jan; Schoepf, Michael UL et al

in Proceedings of the 18th International Conference on the European Energy Market (EEM) (2022, September)

There are different flexibility options to align power systems to volatile feed-in of renewable electricity sources. The flexibility options differ in the dimensions of time, spatiality, and resource type ... [more ▼]

There are different flexibility options to align power systems to volatile feed-in of renewable electricity sources. The flexibility options differ in the dimensions of time, spatiality, and resource type. To make policy decisions on future energy systems, it is necessary to get a top-down indication of how much power system flexibility is needed. With the ongoing energy transition, there is yet no comprehensive overview of indicators that describe which dimension of flexibility will be necessary to what extent for different energy systems. Therefore, this paper provides a first overview of indicators that can be used to assess the necessity of power system flexibility. Thus, we do a systematic literature review to identify indicators that allow us to estimate the necessity of power system flexibility. We conduct a meta-analysis of these indicators and categorize them as indicators that either stand for an increasing or decreasing necessity of power system flexibility. Our paper can help inform policy, assess needed changes to system operations, increase stakeholder acceptance and investor confidence in implementing new technology and measures. [less ▲]

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See detailJoint Beam Placement and Load Balancing Optimization for Non-Geostationary Satellite Systems
Bui, Van-Phuc; Chien, Trinh-Van; Lagunas, Eva UL et al

in IEEE International Mediterranean Conference on Communications and Networking (IEEE MediCom), Athens, Greece, Sept. 2022 (2022, September)

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See detailLearning to Optimize: Balancing Two Conflict Metrics in MB-HTS Networks
Bui, Van-Phuc; Chien, Trinh-Van; Lagunas, Eva UL et al

in Advanced Satellite Multimedia Conference / Signal Processing for Space Communications Workshop (ASMS), Gratz, Viena, Sept. 2022 (2022, September)

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See detailSpace-as-a-Service: A Framework and Taxonomy of -as-a-Service Concepts for Space
Hein, Andreas UL; Bruce Rosete, Citlali UL

in Proceedings of the International Astronautical Congress 2022 (2022, September)

The servitization of space is introducing profound change, challenging established companies with new business models, and significantly lowering the entry barrier to space. New types of services such as ... [more ▼]

The servitization of space is introducing profound change, challenging established companies with new business models, and significantly lowering the entry barrier to space. New types of services such as Mission-as-a-Service, Satellite-as-a-Service, Constellation-as-a-Service, etc., are introduced. However, what these notions mean is not clear and in practice, they are often used with contradicting meanings. This paper aims to provide an initial survey of various new service concepts in the space domain and develops a taxonomy and framework for classifying these emerging services with their underlying systems. A particular emphasis is put on distinguishing novel, "New Space" services from traditional space services. We find that these new space services differ, compared to traditional space services in at least three aspects: New space services have their origin in a transition from a product-to a use-oriented business model and make reference to Cloud computing and its underlying techniques such as virtualization. We conclude that analogous to the terrestrial impact of Cloud computing on the emergence of numerous e-commerce start-ups, we might see a similar surge of in-space applications, building on a new space service backbone. Such a development is likely going to be enabled by the shift from traditionally high capital expenditures of developing space applications to operating expenses, thereby lowering the entry barrier. [less ▲]

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See detailObfuscating LLVM Intermediate Representation Source Code with NSGA-II
de la Torre, Juan Carlos; Aragó-Jurado, José Miguel; Jareño, Javier et al

in 15th Intl. Conf. on Computational Intelligence in Security for Information Systems (CISIS'22) (2022, September)

With the generalisation of distributed computing paradigms to sustain the surging demands for massive processing and data-analytic capabilities, the protection of the intellectual property tied to the ... [more ▼]

With the generalisation of distributed computing paradigms to sustain the surging demands for massive processing and data-analytic capabilities, the protection of the intellectual property tied to the executed programs transferred onto these remote shared platforms becomes critical. A more and more popular solution to this problem consists in applying obfuscating techniques, in particular at the source code level. Informally, the goal of obfuscation is to conceal the purpose of a program or its logic without altering its functionality, thus preventing reverse-engineering on the program even with the help of computing resources. This allows to protect software against plagiarism, tampering, or finding vulnerabilities that could be used for different kinds of attacks. The many advantages of code obfuscation, together with its low cost, makes it a popular technique. This paper proposes a novel methodology for source code obfuscation relying on the reference LLVM compiler infrastructure that can be used together with other traditional obfuscation techniques, making the code more robust against reverse engineering attacks. The problem is defined as a Multi-Objective Combinatorial Optimization (MOCO) problem, where the goal is to find sequences of LLVM optimizations that lead to highly obfuscated versions of the original code. These transformations are applied to the back-end pseudo- assembly code (i.e., LLVM Intermediate Representation), thus avoiding any further optimizations by the compiler. Three different problem flavours are defined and solved with popular NSGA-II genetic algorithm. The promising results show the potential of the proposed technique. [less ▲]

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See detailGNC of a cargo spacecraft for on-orbit servicing of Herschel at L2
Siena, Andrea; Mahfouz, Ahmed UL; Menzio, Davide et al

in IAC 2022 congress proceedings, 73rd International Astronautical Congress (IAC) (2022, September)

t is anticipated that space exploration will need to rely on In Situ Resource Utilization (ISRU) in order toextend spacecraft lifetime and/or reduce the missions cost and/or the cruise time. For the Moon ... [more ▼]

t is anticipated that space exploration will need to rely on In Situ Resource Utilization (ISRU) in order toextend spacecraft lifetime and/or reduce the missions cost and/or the cruise time. For the Moon and, inthe future, Mars colonization, relying on in-situ resources is a necessary step to become independent fromthe Earth. The possibility to produce resources on the Moon is advantageous for those missions that aretoo far from the Earth to be resupplied. At the SnT Research Centre, the Luxembourg Space Agency issupporting a feasibility study to assess the benefit of on-orbit servicing (OOS), exploiting lunar resourcesfor the Herschel Space Observatory. Herschel ended its operations in 2013 as a consequence of the depletionof its coolant and, in turn, of the capability of cooling down its instruments. To extend its operations,a resupply mission has been envisaged relying on an adapted cargo spacecraft employed in lunar gatewayoperations. This paper deals with the trajectory design and optimization of the cargo on its journey from theMoon to rendezvous with Herschel and with orbit and attitude control. Considering Herschel’s orientationon its orbit, with the sunshield in the direction of the Sun and the need to access to Herschel’s rear panelto perform the resupply operation, a final approach along the negative x-axis, where the primaries lie, isconsidered. A multiple shooting technique is used to perform a flanking manoeuvre. Moreover, an attitudecontrol algorithm is adopted to track the attitude trajectory provided by the guidance algorithms which, inturn, ensure minimum thrusting errors of the cargo spacecraft and a continuous visibility of Herschel. Infuture works, different perturbations will be considered and angular rates induced by the movement of therobotic arms will be compensated [less ▲]

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See detailRadio Regulation Compliance of NGSO Constellations’ Interference towards GSO Ground Stations
Jalali, Mahdis UL; Ortiz Gomez, Flor de Guadalupe UL; Lagunas, Eva UL et al

in IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 12–15 September 2022, Virtual Conference (2022, September)

The commercial low earth orbiting (LEO) satellite constellations have shown unprecedented growth. Accordingly, the risk of generating harmful interference to the geostationary orbit (GSO) satellite ... [more ▼]

The commercial low earth orbiting (LEO) satellite constellations have shown unprecedented growth. Accordingly, the risk of generating harmful interference to the geostationary orbit (GSO) satellite services increases with the number of satel- lites in such mega-constellations. As the GSO arc encompasses the primary and existing satellite assets providing essential fixed and broadcasting satellite services, the interference avoidance for this area is of the utmost importance. In particular, non- geostationary orbit (NGSO) operators should comply with the regulations set up both by their national regulators and by the International Telecommunications Union (ITU) to minimize the impact of emissions on existing GSO and non-GSO systems. In this paper, we first provide an overview of the most recent radio regulations that dictate the NGSO-GSO spectral co-existence. Next, we analyze the NGSO-GSO radio frequency interference for the downlink scenario, following the so-called time-simulation methodology introduced by ITU. The probability distribution of aggregated power flux-density for NGSO co-channel interference is evaluated and assessed, adopting different degrees of exclusion angle strategy for interference avoidance. We conclude the paper by discussing the resulting implications for the continuity of operation and service provision and we provide remarks for future work [less ▲]

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See detailPose Estimation of a Known Texture-Less Space Target using Convolutional Neural Networks
Rathinam, Arunkumar UL; Gaudilliere, Vincent UL; Pauly, Leo UL et al

in 73rd International Astronautical Congress, Paris 18-22 September 2022 (2022, September)

Orbital debris removal and On-orbit Servicing, Assembly and Manufacturing [OSAM] are the main areas for future robotic space missions. To achieve intelligence and autonomy in these missions and to carry ... [more ▼]

Orbital debris removal and On-orbit Servicing, Assembly and Manufacturing [OSAM] are the main areas for future robotic space missions. To achieve intelligence and autonomy in these missions and to carry out robot operations, it is essential to have autonomous guidance and navigation, especially vision-based navigation. With recent advances in machine learning, the state-of-the-art Deep Learning [DL] approaches for object detection, and camera pose estimation have advanced to be on par with classical approaches and can be used for target pose estimation during relative navigation scenarios. The state-of-the-art DL-based spacecraft pose estimation approaches are suitable for any known target with significant surface textures. However, it is less applicable in a scenario where the target is a texture-less and symmetric object like rocket nozzles. This paper investigates a novel ellipsoid-based approach combined with convolutional neural networks for texture-less space object pose estimation. Also, this paper presents the dataset for a new texture-less space target, an apogee kick motor, which is used for the study. It includes the synthetic images generated from the simulator developed for rendering synthetic space imagery. [less ▲]

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See detailThe Prosody of Cheering in Sport Events
Zygis, Marzena; Wesolek, Sarah; Hosseini Kivanani, Nina UL et al

in Proc. Interspeech 2022 (2022, September)

Motivational speaking usually conveys a highly emotional message and its purpose is to invite action. The goal of this paper is to investigate the prosodic realization of one particular type of cheering ... [more ▼]

Motivational speaking usually conveys a highly emotional message and its purpose is to invite action. The goal of this paper is to investigate the prosodic realization of one particular type of cheering, namely inciting cheering for single addressees in sport events (here, long-distance running), using the name of that person. 31 native speakers of German took part in the experiment. They were asked to cheer up an individual marathon runner in a sporting event represented by video by producing his or her name (1-5 syllables long). For reasons of comparison, the participants also produced the same names in isolation and carrier sentences. Our results reveal that speakers use different strategies to meet their motivational communicative goals: while some speakers produced the runners’ names by dividing them into syllables, others pronounced the names as quickly as possible putting more emphasis on the first syllable. A few speakers followed a mixed strategy. Contrary to our expectations, it was not the intensity that mostly contributes to the differences between the different speaking styles (cheering vs. neutral), at least in the methods we were using. Rather, participants employed higher fundamental frequency and longer duration when cheering for marathon runners. [less ▲]

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