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See detailIntegration of backscatter communication with multi-cell NOMA: a spectral efficiency optimization under imperfect SIC
Khan, Wali Ullah UL; Lagunas, Eva UL; Mahmood, Asad UL et al

Poster (2022, November 03)

Future wireless networks are expected to connect large-scale low-powered communication devices using the available spectrum resources. Backscatter communications (BC) is an emerging technology towards ... [more ▼]

Future wireless networks are expected to connect large-scale low-powered communication devices using the available spectrum resources. Backscatter communications (BC) is an emerging technology towards battery-free transmission in future wireless networks by leveraging ambient radio frequency (RF) waves that enable communications among wireless devices. Non-orthogonal multiple access (NOMA) has recently drawn significant attention due to its high spectral efficiency. The combination of these two technologies can play an important role in the development of future networks. This paper proposes a new optimization approach to enhance the spectral efficiency of nonorthogonal multiple access (NOMA)-BC network. Our framework simultaneously optimizes the power allocation of base station and reflection coefficient (RC) of the backscatter device in each cell under the assumption of imperfect signal decoding. The problem of spectral efficiency maximization is coupled on power and RC which is challenging to solve. To make this problem tractable, we first decouple it into two subproblems and then apply the decomposition method and Karush-Kuhn-Tucker conditions to obtain the efficient solution. Numerical results show the performance of the proposed NOMA-BC network over the pure NOMA network without BC. [less ▲]

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See detailLie superalgebras of Krichever-Novikov type and their central extensions
Schlichenmaier, Martin UL

Scientific Conference (2022, November 02)

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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 detailUsing Diagnostic Classification Models to map first graders’ cognitive development pathways in the Luxembourgish school monitoring program: a pilot study in the domain of numbers & operations
Inostroza Fernandez, Pamela Isabel UL; Michels, Michael Andreas UL; Sonnleitner, Philipp UL

Scientific Conference (2022, November)

Educational large-scale assessments aim to evaluate school systems’ effectiveness by typically looking at aggregated levels of students’ performance. The developed assessment tools or tests are not ... [more ▼]

Educational large-scale assessments aim to evaluate school systems’ effectiveness by typically looking at aggregated levels of students’ performance. The developed assessment tools or tests are not intended or optimized to be used for diagnostic purposes on an individual level. In most cases, the underlying theoretical framework is based on national curricula and therefore too blurry for diagnostic test construction, and test length is too short to draw reliable inferences on individual level. This lack of individual information is often unsatisfying, especially for participating students and teachers who invest a considerable amount of time and effort, not to speak about the tremendous organizational work needed to realize such assessments. The question remains, if the evaluation could not be used in an optimized way to offer more differentiated information on students’ specific skills. The present study explores the potential of Diagnostic Classification Models (DCM) in this regard, since they offer crucial information for policy makers, educators, and students themselves. Instead of a ranking of, e.g., an overall mathematics ability, student mastery profiles of subskills are identified in DCM, providing a rich base for further targeted interventions and instruction (Rupp, Templin & Henson, 2010; von Davier, M., & Lee, Y. S., 2019). A prerequisite for applying such models is well-developed, and cognitively described items that map the assessed ability on a fine-grained level. In the present study, we drew on 104 items that were developed on base of detailed cognitive item models for basic Grade 1 competencies, such as counting, as well as decomposition and addition with low numbers and high numbers (Fuson, 1988, Fritz & Ricken, 2008, Krajewski & Schneider, 2009). Those items were spread over a main test plus 6 different test booklets and administered to a total of 5963 first graders within the Luxembourgish national school monitoring Épreuves standardisées. Results of this pilot study are highly promising, giving information about different student’s behaviors patterns: The final DCM was able to distinguish between different developmental stages in the domain of numbers & operations, on group, as well as on individual level. Whereas roughly 14% of students didn’t master any of the assessed competencies, 34% of students mastered all of them including addition with high numbers. The remaining 52% achieved different stages of competency development, 8% of students are classified only mastering counting, 15% of students also can master addition with low numbers, meanwhile 20% of students additionally can master decomposition, all these patterns reflect developmental models of children’s counting and concept of numbers (Fritz & Ricken, 2008; see also Braeuning et al, 2021). Information that could potentially be used to substantially enhance large-scale assessment feedback and to offer further guidance for teachers on what to focus when teaching. To conclude, the present results make a convincing case that using fine-grained cognitive models for item development and applying DCMs that are able to statistically capture these nuances in student response behavior might be worth the (substantially) increased effort. References: Braeuning, D. et al (2021)., Long-term relevance and interrelation of symbolic and non-symbolic abilities in mathematical-numerical development: Evidence from large-scale assessment data. Cognitive Development, 58, https://doi.org/10.1016/j.cogdev.2021.101008. Fritz, A., & Ricken, G. (2008). Rechenschwäche. utb GmbH. Fuson, K. C. (1988). Children's counting and concepts of number. Springer-Verlag Publishing. Rupp, A. A., Templin, J. L., & Henson, R. A. (2010). Diagnostic measurement: Theory, methods, and applications. New York, NY: Guildford Press. Von Davier, M., & Lee, Y. S. (2019). Handbook of diagnostic classification models. Cham: Springer International Publishing. [less ▲]

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See detailMO-Gym: A Library of Multi-Objective Reinforcement Learning Environments
Alegre, Lucas Nunes; Felten, Florian UL; Talbi, El-Ghazali UL et al

Scientific Conference (2022, November)

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See detailValidation and Psychometric Analysis of 32 cognitive item models spanning Grades 1 to 7 in the mathematical domain of numbers & operations
Michels, Michael Andreas UL; Hornung, Caroline UL; Gamo, Sylvie UL et al

Scientific Conference (2022, November)

Today’s educational field has a tremendous hunger for valid and psychometrically sound items to reliably track and model students’ learning processes. Educational large-scale assessments, formative ... [more ▼]

Today’s educational field has a tremendous hunger for valid and psychometrically sound items to reliably track and model students’ learning processes. Educational large-scale assessments, formative classroom assessment, and lately, digital learning platforms require a constant stream of high-quality, and unbiased items. However, traditional development of test items ties up a significant amount of time from subject matter experts, pedagogues and psychometricians and might not be suited anymore to nowadays demands. Salvation is sought in automatic item generation (AIG) which provides the possibility of generating multiple items within a short period of time based on the development of cognitively sound item templates by using algorithms (Gierl & Haladyna, 2013; Gierl et al., 2015). The present study psychometrically analyses 35 cognitive item models that were developed by a team of national subject matter experts and psychometricians and then used for algorithmically producing items for the mathematical domain of numbers & shapes for Grades 1, 3, 5, and 7 of the Luxembourgish school system. Each item model was administered in 6 experimentally varied versions to investigate the impact of a) the context the mathematical problem was presented in, and b) problem characteristics which cognitive psychology identified to influence the problem solving process. Based on samples from Grade 1 (n = 5963), Grade 3 (n = 5527), Grade 5 (n = 5291), and Grade 7 (n = 3018) collected within the annual Épreuves standardisées, this design allows for evaluating whether psychometric characteristics of produced items per model are a) stable, b) can be predicted by problem characteristics, and c) are unbiased towards subgroups of students (known to be disadvantaged in the Luxembourgish school system). After item calibration using the 1-PL model, each cognitive model was analyzed in-depth by descriptive comparisons of resulting IRT parameters, and the estimation of manipulated problem characteristics’ impact on item difficulty by using the linear logistic test model (LLTM, Fischer, 1972). Results are truly promising and show negligible effects of different problem contexts on item difficulty and reasonably stable effects of altered problem characteristics. Thus, the majority of developed cognitive models could be used to generate a huge number of items (> 10.000.000) for the domain of numbers & operations with known psychometric properties without the need for expensive field-trials. We end with discussing lessons learned from item difficulty prediction per model and highlighting differences between the Grades. References: Fischer, G. H. (1973). The linear logistic test model as an instrument in educational research. Acta Psychologica, 36, 359-374. Gierl, M. J., & Haladyna, T. M. (Eds.). (2013). Automatic item generation: Theory and practice. New York, NY: Routledge. Gierl, M. J., Lai, H., Hogan, J., & Matovinovic, D. (2015). A Method for Generating Educational Test Items That Are Aligned to the Common Core State Standards. Journal of Applied Testing Technology, 16(1), 1–18. [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 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 detailMaaS modelling: a review of factors, customers’ profiles, choices and business models
Cisterna, Carolina UL; Negarsadat, Madani; Bandiera, Claudia UL et al

Scientific Conference (2022, November)

Mobility-as-a-Service (MaaS) is regarded as one of the emerging solutions to offer integrated, seamless, and flexible multi-modal mobility services as an alternative to privately owned mobility resources ... [more ▼]

Mobility-as-a-Service (MaaS) is regarded as one of the emerging solutions to offer integrated, seamless, and flexible multi-modal mobility services as an alternative to privately owned mobility resources. MaaS gathers collective services such as public transport, shared solutions and other types of new mobility (e.g., on-demand ride services) and ancillary services (e.g., discounted parking) in bundles, accessed via monthly subscriptions. The key distinction between this system and traditional multi-modal systems managed by independent service providers is that payment for services is done through a single digital platform. MaaS is expected to change the way users will choose their modes of transport to reach their daily activities, and how service providers will generate profits, cooperate, and compete. From a wider perspective, MaaS is expected to favour a decline in car ownership and foster sustainable mobility, especially if the services increase the efficiency and utilisation of mass transit. To that aim, it is critical to obtain a thorough grasp of feasible and sustainable business models that suit the diverse needs of customers as well as the diverse and often competing objectives of service providers. In contrast, traditional transportation planning models typically assess solutions in a limited period of time (i.e., the peak hour) and use different simplifying assumptions (e.g., single trip-based choices, no interaction between service providers). This paper aims to provide a general modelling framework relating all main actors in the MaaS ecosystem and identify and discuss all factors that are considered relevant to define customers’ profiles and business models based on a comprehensive review of the literature. Gaps and challenges from the current studies are highlighted and future research directions are recommended. [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 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 detailSecure and Distributed Assessment of Privacy-Preserving Releases of GWAS
Pascoal, Túlio UL; Decouchant, Jérémie; Volp, Marcus UL

in ACM/IFIP International Middleware Conference (2022, November)

Genome-wide association studies (GWAS) identify correlations between the genetic variants and an observable characteristic such as a disease. Previous works presented privacy-preserving distributed ... [more ▼]

Genome-wide association studies (GWAS) identify correlations between the genetic variants and an observable characteristic such as a disease. Previous works presented privacy-preserving distributed algorithms for a federation of genome data holders that spans multiple institutional and legislative domains to securely compute GWAS results. However, these algorithms have limited applicability, since they still require a centralized instance to decide whether GWAS results can be safely disclosed, which is in violation to privacy regulations, such as GDPR. In this work, we introduce GenDPR, a distributed middleware that leverages Trusted Execution Environments (TEEs) to securely determine a subset of the potential GWAS statistics that can be safely released. GenDPR achieves the same accuracy as centralized solutions, but requires transferring significantly less data because TEEs only exchange intermediary results but no genomes. Additionally, GenDPR can be configured to tolerate all-but-one honest-but-curious federation members colluding with the aim to expose genomes of correct members. [less ▲]

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See detailAUSLEGUNG eines BIOMECHANISCHEN TESTSTANDES für das BECKEN einschließlich der MUSKELKRÄFTE des GANGZYKLUS
Soliman, Ahmed Abdelsalam Mohamed UL; Ricci, Pierre-Louis; Kedziora, Slawomir UL et al

Scientific Conference (2022, October 28)

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See detailBiomechanische Untersuchung zu verschiedenen Verfahren der Stabilisierung von Insuffizienzfrakturen des vorderen Beckenringes
Gerich, Torsten; Soliman, Ahmed Abdelsalam Mohamed UL; Ricci, Pierre-Louis et al

Poster (2022, October 26)

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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 detailImpacting the computerization and Digitalization in Luxembourg: the case of teachers and education
Noguera, Carmen UL

Scientific Conference (2022, October 21)

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See detail“Challenge accepted”. The many sources to catch the history of virality and memes
Schafer, Valerie UL

Scientific Conference (2022, October 20)

Gifs and memes (Kaplan and Nova, 2016), “buzz” on the Web and social networks are inherent to digital cultures since the very first steps of the Web (i.e., Godwin’s Law, Dancing babies, Hamster Dance, cf ... [more ▼]

Gifs and memes (Kaplan and Nova, 2016), “buzz” on the Web and social networks are inherent to digital cultures since the very first steps of the Web (i.e., Godwin’s Law, Dancing babies, Hamster Dance, cf. McGrath, 2019). Virality has developed and changed over time, may it be related to forms (macro images, videos, etc.) and platforms (YouTube, 4Chan, Twitter, TikTok, etc.), audiences, curation and dissemination (with features encouraging spreadability within social platforms), etc., while relying on some patterns that were identified by Shifman (2014), Milner (2018), Jenkins (2009) and others. However, history and diachronic approaches still remain underrepresented in studies of online virality, although Finn Brunton’s Spam, Jason Eppink’s visual history of gifs (2014), or the Memes entry in The Sage Handbook of Web History (McGrath, 2019) can be mentioned. Historicizing virality through times, spaces and platforms is at the heart of the Hivi project at C2DH, University of Luxembourg (https://hivi.uni.lu). While starting to historicize these “Internet phenomena”, may it be Numa Numa Guy, Leave Britney Alone, Grumpy Cat, the Harlem Shake, Distracted Boyfriends, etc., challenges related to sources become more and more obvious: researchers have to deal with ephemerality as well as data overload, with several spaces of heritagization on the live and archived web, with gaps, silences and noises, issues of searchability in web archives, etc. This presentation focused on a case study, the Harlem Shake, to first demonstrate the variety of sources and spaces (physical and digital) that may be used to retrieve and rebuild this phenomenon (i.e., press, audiovisual content, archived web in several institutions, live web and platforms, etc.). It then presented the challenges related to this kind of reconstruction that is also strongly intertwining vernacular and commercial cultures; sound, video, textual contents; local as well as international spaces, etc. [less ▲]

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See detailSpecial ECREA panel : Rethinking digital sources — making web archives useful for future scholars
Schafer, Valerie UL

Scientific Conference (2022, October 20)

The aim of this panel was to draw attention to the large number of archived web collections, and to rethink the challenges and possibilities that they constitute for studies of past and present mediated ... [more ▼]

The aim of this panel was to draw attention to the large number of archived web collections, and to rethink the challenges and possibilities that they constitute for studies of past and present mediated communication. The point of departure is the international network WARCnet, Web ARChive studies net- work researching web domains and events (warcnet.eu), that is composed of humanities scholars, IT-developers, and web archivists, and that aims at promoting national and transnational research that will help us to understand the history of (trans)national web domains and of transnational events on the web, drawing on the increasingly important digital cultural heritage held in national web archives. [less ▲]

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See detail“Small is impactful”. Memes and Politics
Pailler, Fred UL; Schafer, Valerie UL

Scientific Conference (2022, October 20)

From the Hampster Dance and the Dancing Baby in the second half of the 1990s to the hijacking meme of Bernie and his mittens at the US presidential inauguration or the images of the Evergreen blocked in ... [more ▼]

From the Hampster Dance and the Dancing Baby in the second half of the 1990s to the hijacking meme of Bernie and his mittens at the US presidential inauguration or the images of the Evergreen blocked in the Suez Canal, memes have become in the last twenty years an important part of our digital cultures (Shifman, 2014), whose often absurd, playful, corrosive and viral character cannot hide also multiple political dimensions. To the question "Do Memes have politics", to paraphrase Langdon Winner (1980), the answer is undoubtedly yes and this presentation aims to analyse the many levels of politics and agencies at stake when studying memes and their impact, in terms of digital cultures, governance, curation, sharing (John, 2017), appropriation by several communities, but also writing of their history. The first part of the presentation unfolded several levels of politics, starting with the most obvious (memes address political aspects, see for example Denisova, 2019 or Askanius and Keller, 2021) to the more hidden levels (politics of meme generators, of heritagization platform like Know your Meme (Pettis, 2021), of curation …). Relying on a diachronic approach, from the Godwin Law to Distracted Boyfriend, through Leave Britney Alone, this part aimed to address both complementary sides of these Internet phenomena: memes as political forms and politics of memes, while underlying some economic, gendered, affective dimensions which are part of their impact. We then examined the consequences of the notion of “impact” and “politics” for the shaping of an history of memes, which is at stake in the Hivi (A history of online virality) project, we are currently conducting, may it be in terms of sources, methods (“scalable” and “medium” reading), or topics (notably claiming for a study of circulation and flow (Jenkins, 2009), of processes, of participation (Milner, 2018) and appropriation, beyond a sole semiotic approach of memes). References Tina Askanius, Nadine Keller, “Murder fantasies in memes: fascist aesthetics of death threats and the banalization of white supremacist violence”, Information, Communication & Society, 2021, vol. 0, n° 0, p. 1 18. Anastasia Denisova, Internet memes and society: social, cultural, and political contexts, New York, Routledge, 2019. Nicholas A. John, The age of sharing, Cambridge, Polity Press, 2017. Henry Jenkins, If It Doesn’t Spread, It’s Dead (Part One): Media Viruses and Memes, 2009 (http://henryjenkins.org/blog/2009/02/if_it_doesnt_spread_its_dead_p.html). Ryan Milner, The world made meme: Public conversations and participatory media, Cambridge MA, The MIT Press, 2018. Ben Tadayoshi Pettis, “Know your Meme and the Homogeneization of Web History”, Internet Histories, 2021 (to be soon published). Limor Shifman, Memes in digital culture, Cambridge MA, The MIT Press, 2014. Langdon Winner, “Do artifacts have politics ?”, Daedalus, vol. 109, n°1, 1980, p. 121-136. [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 detailRetrieving traces of the Luxembourg WebSphere through its first websites
Noguera, Carmen UL

Scientific Conference (2022, October 18)

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See detailLet’s talk about web archiving … three institutions, many possibilities
Schafer, Valerie UL

Scientific Conference (2022, October 18)

This presentation focused on three oral interviews I conducted during the COVID crisis, respectively with the BnL (Bibliothèque nationale du Luxembourg, Els, 2020) in Luxembourg and with INA (Institut ... [more ▼]

This presentation focused on three oral interviews I conducted during the COVID crisis, respectively with the BnL (Bibliothèque nationale du Luxembourg, Els, 2020) in Luxembourg and with INA (Institut national de l’audiovisuel, Schafer, 2020b) and BnF (Bibliothèque nationale de France, Gebeil et al., 2020) in France, to document their web archiving practices and choices during the pandemic. Oral histories not only document the collections and often hidden practices of crawling, selecting, curating and preserving data. They also provide a lot of information on living collections, on the challenges at stake and on human participation in this process. It also enlightens values and governance of web archives and web archiving practices (Schafer and Winters, 2021). Moreover, documenting web archiving is necessary for the current and future work of researchers and may help them to better understand their datasets, the representativeness of collections, bias and limits as well as the strengths of these web archives. Our presentation first compared the practices in the three institutions we selected as case studies for this presentation, in terms of perimeters, curation, stakeholders, targets - INA being a specific case as it focused more precisely on Twitter and retrieved data from the Twitter API, while the BnL and BnF targeted websites more widely (and some social networks but in a less systematic way). We also explained how these oral histories may help to better understand the shaping of web archives. We finally gave several concrete examples of the usefulness of this material for researchers who conduct research on web archives, and more specifically on the COVID crisis, in terms of transnational approaches, and silences and noises in web archives (Brügger, 2018), etc. [less ▲]

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See detailKeynote by panel on Looking ahead: after web (archives)?
Noguera, Carmen UL

Scientific Conference (2022, October 18)

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See detailRetrieve me if you can... Women and COVID through Web archives
Schafer, Valerie UL

Scientific Conference (2022, October 18)

The COVID crisis has been a shared worldwide and collective experience from March 2020 and lot of voices have echoed each other, may it be related to grief, lockdown, masks and vaccines, homeschooling ... [more ▼]

The COVID crisis has been a shared worldwide and collective experience from March 2020 and lot of voices have echoed each other, may it be related to grief, lockdown, masks and vaccines, homeschooling, etc. However, this unprecedented crisis has also deepened asymmetries and failures within societies, in terms of occupational fields, economic inequalities, health and sanitary access, and we could extend the inventory of these hidden and more visible gaps that were reinforced during the crisis. Women and gender were also at stake when it came to this sanitary crisis, may it be to discuss the better management of the crisis by female politicians, domestic violence during the lockdown, decreasing production of papers by female research scientists, homeschooling and mental load of women, etc. In December 2021, our AWAC2 team submitted several topics to the IIPC (International Internet Preservation Consortium) community and invited the international organization to select one of them that the team would investigate in depth, based on the unique IIPC Covid collection of web archives. Women, gender and COVID was the winning topic. As a cohort team within the AUT (Archives Unleashed Team) program, the AWAC2 team benefited from a privileged access to this collection, thanks to Archive-It and through ARCH, and from regular mentorship by the AUT team. It allowed us to investigate and analyse this huge collection of 5.3 TB, 161 757 lines for the CSV on domain frequency CSV, 8,738,751 lines for the CSV related to plain text of web pages. Accepting the challenge, the AWAC2 team organized a datathon in March 2022 in Luxembourg to investigate and retrieve the many traces of women, gender and COVID in web archives, while mixing close and distant reading. This panel, chaired by Valérie Schafer, aimed to present this research, entwining technical, epistemological, and methodological issues and challenges with our results. Valérie Schafer began the panel by presenting an overview of the project, including a presentation of the IIPC corpus, of the AUT cohort program and of the research topic. Karin de Wild and Joshgun Sirajzade presented the AUT tools and interfaces, the technical challenges of the corpus, the choices we made (and notably with regards to multilingualism) as well as the tools and methodologies that were used. Finally, Susan Aasman and Sophie Gebeil presented some results and challenges of this research. [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 detailHistoire des territoires belges annexés au IIIe Reich
Brüll, Christoph UL

Scientific Conference (2022, October 15)

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See detailLiteracy mit Kleinkindern mit Erzieher*Innen und Eltern in Kindertagestätten
Kirsch, Claudine UL

Scientific Conference (2022, October 14)

In 2017 führte Luxemburg ein mehrsprachiges Programm in der frühkindlichen Bildung ein: kleine Kinder lernen Luxemburgisch und machen sich mit Französisch vertraut, außerdem werden ihre Familiensprachen ... [more ▼]

In 2017 führte Luxemburg ein mehrsprachiges Programm in der frühkindlichen Bildung ein: kleine Kinder lernen Luxemburgisch und machen sich mit Französisch vertraut, außerdem werden ihre Familiensprachen wertgeschätzt. Literacy Aktivitäten in mehreren Sprachen sowie eine enge Zusammenarbeit mit Eltern sollen dies gewährleisten. Eine Umfrage sowie Beobachtungen im Rahmen des Forschungsprojekts „Zusammenarbeit mit Eltern und Multiliteracies“ (COMPARE) zeigen, dass viele Erzieher*Innen Kindern in mehreren Sprachen vorlesen, dass die Qualität der Interaktionen aber sehr unterschiedlich ist. Eine Umfrage mit Eltern verdeutlicht zudem, dass etwa die Hälfte der Teilnehmer ihren Kindern in der Familiensprachen vorlasen. Dieser Beitrag wird Einblicke in die ersten Ergebnisse der Studie COMPARE geben mit besonderem Fokus auf die Literacy Aktivitäten, die Eltern gemeinsam mit Erzieher*Innen in drei Kindertagesstätten in 2020-2021 durchführten. Wir zeigen, dass die gemeinsamen Aktivitäten mit den Eltern zur Entwicklung von Multiliteracy Praktiken und der Wertschätzung von Familiensprachen führen kann, wenn die Erzieher*Innen ein gutes Verständnis von Literacy haben, in Bildungspartnerschaften investieren und sich Sprachhierarchien bewusst sind. [less ▲]

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See detailOn the (alleged) disappearance of repair since the 1970s
Krebs, Stefan UL

Scientific Conference (2022, October 14)

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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 Panner Selvam, Karthick; Brorsson, Mats Hakan (Eds.) Performance Modeling of Weather Forecast Machine Learning for Efficient HPC (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 detailNvidia Omniverse for Active Space Debris Removal Missions, an Overview
Li, Xiao UL; Richard, Antoine UL; Loumpasefski, Olga-Orsalia UL et al

Scientific Conference (2022, October 13)

Earth orbits have an increasingly worrying space debris pollution problem caused by millions of human-made objects left in space. These are becoming a hazard for current and future space missions. Many ... [more ▼]

Earth orbits have an increasingly worrying space debris pollution problem caused by millions of human-made objects left in space. These are becoming a hazard for current and future space missions. Many solutions to deal with space debris problems have been proposed, including Active Space Debris Removal (ASDR) methods. In this thriving field, various technologies are under development, among them, systems based on tethers, nets, lasers, or robotic arms can be found. However, testing such systems on earth is challenging, recreating space-like conditions, such as accurate contact dynamics under microgravity, is particularly difficult. Nonetheless, it is of paramount importance to offer testing environments for clean space technologies, as space is unforgiving, and space devices must go through thorough evaluation processes to ensure peak efficiency. The HELEN project aims at fulfilling this very need. Building on one of the most advanced simulation frameworks, it will provide photo-realistic rendering, an accurate physical simulation of the space environment, and eventually, through Hardware-In-the-Loop (HIL), simulation of microgravity in ground facilities. This project is the result of the collaboration between SpaceR (University of Luxembourg), and Spacety (Industry). This simulation will be used to test FlexeS, an ASDR capturing system, which is under development. In HELEN, the accuracy of the physics is particularly important, as FlexeS will be validated through simulated HIL scenarios. Hence, a lifelike depiction of the microgravity environment, as well as the collisions, is critical. Moreover, to intercept and grab the debris FlexeS will rely on computer vision algorithms, thus photo-realistic graphics, allowing for lifelike visualizations are required. Furthermore, for future HIL testing, the ROS bridge and real-time communication capacity are crucial to connect the virtual world with the Zero-G robotic facility of the University of Luxembourg. In such a manner, FlexeS will be visualized in the space surroundings while simultaneously undergoing hardware experiments. With all these constraints in mind, Nvidia's Issac Sim was selected to create on-orbit dynamic scenarios. It not only meets all the requirements above but also provides a variety of sensors. Consequently, HELEN is creating on-orbit simulations featuring a CubeSat embedded with FlexeS, and debris circling the Earth. The scenarios showcase the digital twin of the capturing system intercepting debris, corresponding to the approaching phase in ASDR missions. Visually speaking, the RTX render engine allows for photo-realistic image generation. Regarding the motion of these objects, force-based astrodynamics is implemented into the simulation following the gravitational equation. Faithful velocities, position, and contacts are inferred by Nvidia's physics engine, PhysX. Scaled real-life values are used for the mass, as well as the orbital velocity and altitude. Thus, accurate simulations of contact dynamics between the system and the debris can be achieved. In the future, using a ROS bridge, the simulation will be connected to the HIL testing system of the Zero-G facility, amounting to a wholesome ASDR testing framework. Overall, the realistic simulations created with Isaac Sim are promising for analyzing clean space technologies. They combine photo-realistic scenes, accurate physics, and in the future, a means to test real hardware systems. [less ▲]

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See detailMeasuring COVID-19 Vaccine Hesitancy: Consistency of Social Media with Surveys
Chen, Ninghan UL; Chen, Xihui UL; Pang, Jun UL et al

in Proceedings of the 2022 International Conference on Social Informatics (2022, October 12)

See detailCentralized or not Centralized? Topology Analysis of the XRP Ledger
Tumas, Vytautas UL; Rivera, Sean UL; Magoni, Damien et al

Scientific Conference (2022, October 12)

XRP is one of the oldest, well-established cryptocurrencies. Despite the popularity of XRP, little is known about its underlying peer-to-peer network. The structural properties of a network impact its ... [more ▼]

XRP is one of the oldest, well-established cryptocurrencies. Despite the popularity of XRP, little is known about its underlying peer-to-peer network. The structural properties of a network impact its efficiency, security and robustness. We aim to close the knowledge gap by providing a detailed analysis of the XRP overlay network. In this paper we examine the graph-theoretic properties of the XRP Network topology and its temporal characteristics. We crawl the XRP Network over two months and collect 1,290 unique network snapshots. We uncover a small group of nodes that act as a networking backbone. In addition, we observe a high network churn, with a third of the nodes changing every five days. Our findings have strong implications for the resilience and safety of the XRP Ledger. [less ▲]

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See detailConcept of an Active Debris Removal 2-step capturing system for small satellites in Low Earth Orbit
Hubert Delisle, Maxime UL; Martinez Luna, Carol UL; Yalcin, Baris Can UL et al

Scientific Conference (2022, October 12)

Space debris brings up two main critical issues: not only a non-sustainable space environment for satellite missions, with orbit saturation, but also the creation of an unsafe place for human-related ... [more ▼]

Space debris brings up two main critical issues: not only a non-sustainable space environment for satellite missions, with orbit saturation, but also the creation of an unsafe place for human-related space missions. Despite being extremely challenging, catching autonomously and harmlessly an uncooperative object tumbling at high velocity demand reliability, compliance, and robustness. Grasping an object in microgravity means having control during the impact, but also keeping the link between the chaser satellite and the debris secure enough to handle the deorbiting phase. Supposing that the GNC installed tackles the synchronization with the debris rotation, so that only a linear translation is necessary to capture, three main problems can occur. The first problem can occur at the impact between the servicer and the debris. Due to the motion-reaction law, the debris could be pushed away if the capturing system does not prevent that motion. Besides, a high stiffness of the system, added to an unexpected strong impact, could damage either the servicer and/or the debris, resulting in a mission failure. Moreover, the need for a secure attach is required to go-on with the deorbit phase without losing the debris. That’s why, thanks to the fruitful collaboration between industry and academia (Spacety Luxembourg - SpaceR research group at the University of Luxembourg), a cutting-edge concept of a two-step capturing mechanism is being designed. Data analysis of trackable objects in LEO reveals an abundant number of CubeSat-shaped satellites, that future constellations might also take advantage of. Consequently, the concept presented is focusing on capturing these, at their end of life. A first ‘soft capture’ ensures that the debris is received softly while dampening any vibrations generated. A gecko-inspired adhesive surface will first receive the debris, preventing it from being pushed away. The property of such dry adhesive is that they do not require a high preload to stick to the surface, while having a very strong adhesion. To absorb most of the vibrations or movements due to the first impact, a compliant mechanism will be integrated behind the adhesive part. To that extent, if the alignment is not perfect, the system has some degrees of freedom, so that no damage can be generated. This compliant and sticky system would prevent the first main two issues of capturing an uncooperative target in microgravity. Then, a ‘hard capture’ secures the debris so that it would be deorbited without being released on the way. This part of the system would either gently squeeze the debris, using controlled adhesive flexible arms, or encircle it, and would be designed in compliance of ESA guidelines for demise. A two-step capturing mechanism is here proposed, taking advantage of bio-inspired dry adhesive technology, and compliant mechanisms, while having ESA guidelines in mind. Bringing the advantage of removing a vast range of objects in orbit, it also allows a reliable capturing, removing risks of generating more debris. Later works would bring attention to architecture that would fit more than a box shape. [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 detailRace and gender homophily in collaborations and citations
Kozlowski, Diego UL; Larivière, Vincent; Sugimoto, Cassidy R. et al

Scientific Conference (2022, October 09)

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See detail3D Modelling for AR and 3D printing in Teacher Training
Ulbrich, Eva; El Bedewy, Shereen; Handl, Julia et al

Scientific Conference (2022, October 07)

School activities integrating students’ environments into teaching aim to develop skills and strategies to solve problems in real-world situations and can be useful in hybrid teaching. Such activities can ... [more ▼]

School activities integrating students’ environments into teaching aim to develop skills and strategies to solve problems in real-world situations and can be useful in hybrid teaching. Such activities can encourage and motivate exploring skills in Science, Technology, Engineering, Arts, and Mathematics (STEAM). Hybrid teaching usually uses technologies and connects virtual and physical worlds. We use technologies like 3D modelling for Augmented Reality (AR) or 3D printing with GeoGebra and created an exercise introducing them in a lecture for pre-service mathematics students. The exercise combines the possibility to introduce these technologies, can be used in hybrid teaching and connects to the Austrian mathematics curriculum. The exercise consists of 3D modelling mathematical mazes that can be explored using AR on handheld devices and can also be 3D printed. We used it in online, offline and hybrid scenarios with pre- and in-service teachers and will show resulting presentations of teacher projects. [less ▲]

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See detailA Secure Authentication Protocol for Cholesteric Spherical Reflectors using Homomorphic Encryption
Arenas Correa, Monica Patricia UL; Bingol, Muhammed Ali; Demirci, Huseyin UL et al

in Lecture Notes in Computer Science (2022, October 06), 13503

Sometimes fingerprint-like features are found in a material. The exciting discovery poses new challenges on how to use the features to build an object authentication protocol that could tell customers and ... [more ▼]

Sometimes fingerprint-like features are found in a material. The exciting discovery poses new challenges on how to use the features to build an object authentication protocol that could tell customers and retailers equipped with a mobile device whether a good is authentic or fake. We are exactly in this situation with Cholesteric Spherical Reflectors (CSRs), tiny spheres of liquid crystals with which we can tag or coat objects. They are being proposed as a potential game-changer material in anti-counterfeiting due to their unique optical properties. In addition to the problem of processing images and extracting the minutiæ embedded in a CSR, one major challenge is designing cryptographically secure authentication protocols. The authentication procedure has to handle unstable input data; it has to measure the distance between some reference data stored at enrollment and noisy input provided at authentication. We propose a cryptographic authentication protocol that solves the problem, and that is secure against semi-honest and malicious adversaries. We prove that our design ensures data privacy even if enrolled data are leaked and even if servers and provers are actively curious. We implement and benchmark the protocol in Python using the Microsoft SEAL library through its Python wrapper PySEAL. [less ▲]

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See detailAugmented Reality in primary education: New learning opportunities for students with learning difficulties in mathematics education
Haas, Ben; Kreis, Yves UL; Lavizcza, Zsolt

Scientific Conference (2022, October 06)

Although there are manifold connections between mathematics, foremost geometry, and the real-world (e.g., architecture, arts, functional objects), integration seldom happens in daily learning lessons in ... [more ▼]

Although there are manifold connections between mathematics, foremost geometry, and the real-world (e.g., architecture, arts, functional objects), integration seldom happens in daily learning lessons in mathematics primary education. Learning three-dimensional geometric shapes, for example, is mainly done in a two-dimensional setting using textbooks instead of three-dimensional settings using technology or didactical material. This circumstance, however, makes it far more difficult for students with learning difficulties in mathematics to understand mathematical properties, recognize shapes in the real world, and understand the possibilities of modulating shapes. Students with learning difficulties learn efficient strategies to apply mathematics to their environment when shapes and connections are visualized with Augmented Reality within the real world. Based on several experiences and studies, we will present and discuss learning mathematics with Augmented Reality in primary education for students with learning difficulties. [less ▲]

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See detailL'espace frontalier franco-luxembourgeois vu depuis le Luxembourg
Brüll, Christoph UL

Scientific Conference (2022, October 02)

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See detailOpenAirInterface as a platform for 5G-NTN Research and Experimentation
Kumar, Sumit UL; Meshram, Ashish Kumar UL; Abdalla, Abdelrahman UL et al

in IEEE Future Networks World Forum (2022, October)

Technical advancements and experimental works for the integration of 5G and Non-Terrestrial Networks (NTN) have gained significant traction over the past few years. NTN components have been officially ... [more ▼]

Technical advancements and experimental works for the integration of 5G and Non-Terrestrial Networks (NTN) have gained significant traction over the past few years. NTN components have been officially included in the 5G ecosystem by 3GPP in the latest Release-17. 5G-NTN research is ongoing and it is desirable to have a platform that facilitates quick prototyping of the proof-of-concept methods. OpenAirInterface(OAI) is an open-source experimental yet 3GPP standard-compliant Software Defined Radio (SDR) based protocol stack that has been widely known for implementing 4G/5G technologies. Due to its proven capabilities and flexibility, OAI is currently in the developmental process of integrating adaptations for the 5G-NTN. In this work, we discuss the peculiar features of OAI which are shaping it towards becoming a preferred tool for research and experimentation related to 5G-NTN. We provide details of completed/ongoing 5G-NTN projects leveraging OAI to achieve their objectives. In particular, we discuss 5G-GOA and 5G-LEO where critical adaptations in OAI are being done to support 5G-NTN usecases. Such adaptations enable direct-access between UE and gNB via transparent payload Geostationary (5G-GOA) and Nongeostationary satellites (5G-LEO). Both projects have closely followed 3GPP discussions over 5G-NTN and the adaptations are compliant with the currently frozen 3GPP Release-17. OAI adaptations from both projects will be merged into the main development branch of OAI. We also provide a future roadmap of OAI towards 5G-NTN development. We believe that the pioneering steps taken in the course of the aforementioned projects will establish OAI as a preferred tool for 5G-NTN research and experimentations. [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 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 detailNon-Coherent Massive MIMO Integration in Satellite Communication
Monzon Baeza, Victor UL; Ha, Vu Nguyen UL; Querol, Jorge UL et al

Scientific Conference (2022, October)

Massive Multiple Input-Multiple Output (mMIMO) technique has been considered an efficient standard to improve the transmission rate significantly for the following wireless communication systems, such as ... [more ▼]

Massive Multiple Input-Multiple Output (mMIMO) technique has been considered an efficient standard to improve the transmission rate significantly for the following wireless communication systems, such as 5G and beyond. However, implementing this technology has been facing a critical issue of acquiring much channel state information. Primarily, this problem becomes more criticising in the integrated satellite and terrestrial networks (3GPP-Release 15) due to the countable high transmission delay. To deal with this challenging problem, the mMIMO-empowered non-coherent technique can be a promising solution. To our best knowledge, this paper is the first work considering employing the non-coherent mMIMO in satellite communication systems. This work aims to analyse the challenges and opportunities emerging with this integration. Moreover, we identified the issues in this conjunction. The preliminary results presented in this work show that the performance measured in bit error rate (BER) and the number of antennas are not far from that required for terrestrial links. Furthermore, thanks to mMIMO in conjunction with the non-coherent approach, we can work in a low signal-to-noise ratio (SNR) regime, which is an excellent advantage for satellite links. [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 detailClimate Risk and Price Jumps
Lehnert, Thorsten UL

Scientific Conference (2022, October)

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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 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 detailChildren’s perspectives on their learning experiences during the pandemic
Kirsch, Claudine UL

Scientific Conference (2022, October)

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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 detailHybridization of GNSS and 5G Measurement for Assured Positioning, Navigation and Timing
González Garrido, Alejandro UL; Querol, Jorge UL; Chatzinotas, Symeon UL

Scientific Conference (2022, October)

Positioning, Navigation and Timing (PNT) services based on the Global Navigation Satellite System (GNSS) have a number of known drawbacks that makes them prone to suffer a disruption. These flaws can be ... [more ▼]

Positioning, Navigation and Timing (PNT) services based on the Global Navigation Satellite System (GNSS) have a number of known drawbacks that makes them prone to suffer a disruption. These flaws can be exploited to disable this service in critical infrastructures. Therefore, the hybridization of GNSS and 5G measurements enabling Assured PNT (APNT) services is growing up and gaining attention by governmental bodies. 5G signals emitted by terrestrial networks and by Low Earth Orbit (LEO) satellites can complement GNSS enhancing their reliability, security and accuracy. For example, the larger Signal-to-Noise Ratio (SNR) of a terrestrial system makes them more difficult to suffer a jamming attack as compared to GNSS signals. A joint data and positioning signal enhances the security and reliability of the APNT solution with, for example, the successful decoding of encrypted data could be used for system authentication. Moreover, a larger signal bandwidth increases the accuracy of the PNT solution. All of these benefits can be extracted from the 5G terrestrial and non-terrestrial networks that transmit the Positioning Reference Signal (PRS). The rationale for these benefits rely on the flexibility of this pilot signal in terms of bandwidth or symbols used for the APNT service. This paper aims to analyse how this flexibility can be optimized to achieve a specific level of accuracy, minimizing the resources used under certain constrains of bandwidth or latency. The results present the optimal parameters to design a 5G PRS waveform with a target scenario constrains. Then, we compare it with the GNSS service and how to benefit when using them in combination. Finally, the paper concludes with the future research lines proposing a joint communications and positioning system as a feedback or closed loop. In such scenario, the user achieved accuracy is sent back to the infrastructure, and using the dynamic PRS flexibility, the system increases or reduces the PRS resources in order to meet the user accuracy requirements. [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 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 detailEnabling Elements of Simulations Digital Twins and its Applicability for Information Superiority in Defence Domain
Aggarwal, Kapish; Bögel, Elias; La Rosa Betancourt, Manuel et al

Scientific Conference (2022, September 29)

The emerging concept of digital twins is the key enabler for modelling and simulations needs of any future-ready entity. Digital twins enable rapid transformation of requirements into capabilities at much ... [more ▼]

The emerging concept of digital twins is the key enabler for modelling and simulations needs of any future-ready entity. Digital twins enable rapid transformation of requirements into capabilities at much lower costs, compared to conventional methods, through enhancement of modularity and scalability. Elements of a modelling and simulations digital twin are discussed in this paper. These capabilities include, but are not limited to, surrogate modelling, optimization, parallelization, high performance computing, cloud architecture design, etc. These concepts are relevant for the integration of modelling and simulations technologies into a single interface digital twin for rapid prototyping and qualification of engineering systems. Use of these emerging technologies leads to significantly less simulation computation time (reduced from hours/days to seconds or even micro-seconds) compared to the conventional methods. Ease-of-collaboration with all stakeholders, reduced testing time, minimal on-site infrastructure requirements are the key cost-reducing advantages found in this study. Applicability of such intelligent and online digital twins for information superiority to enhance cybersecurity and on-board threat assessment of space-based (defence) services is analysed. The use of these synchronized and interoperable capabilities mitigates both reversible and non-reversible physical and cyber threats to defence space infrastructure. [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 detailThe use of media in language teaching
Lejot, Eve UL; Krames, Marion

Scientific Conference (2022, September 24)

Multilingual teaching and the promotion of multilingualism among students are important principles of the University of Luxembourg. For their implementation, a variety of e-learning resources are used ... [more ▼]

Multilingual teaching and the promotion of multilingualism among students are important principles of the University of Luxembourg. For their implementation, a variety of e-learning resources are used, adapted to the needs of the learners. We will give an overview of new multimodal communication practices and methods used by learners in multilingual contexts which naturally lead teachers to rethink their approach and incorporate media into their teaching strategies. The hybrid nature of devices (computers, tablets, televisions, smartphones, paper, interactive whiteboards, etc.) and digital tools (document sharing platforms, online correction tools, interactive exercises, online learning programmes, dictionaries, video editing software, automatic pronunciation correction, etc.) offer a great potential to interactive and mobile teaching and learning. We will illustrate this potential by giving an example of how to develop text production competence in Chinese as a foreign language in a motivating way using the content management system Moodle. Our reflection aims at optimising the quality of language teaching both in and out of the classroom. [less ▲]

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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 detailMonitoring and Early Detection of Wildfires Using Multiple-payload Fractionated Spacecraft
Alandihallaj, Mohammadamin UL; Emami, M. Reza

Scientific Conference (2022, September 20)

The paper discusses the deployment of multiple-payload fractionated spacecraft as a surveillance system for autonomously monitoring and detecting wildfires at early stages in any area on the Earth’s ... [more ▼]

The paper discusses the deployment of multiple-payload fractionated spacecraft as a surveillance system for autonomously monitoring and detecting wildfires at early stages in any area on the Earth’s surface. The fractionated system, consisting of 12 operational CubeSats, four reserved CubeSats, and one Mothership, acquires images in 13 spectral bands within the visible, near infrared, and short-wave infrared regions with high spatial resolutions. A dynamic fire-hazard index is introduced, based on geographic coordinates, environmental parameters, and weather conditions, to prioritize the areas for the probability of wildfires. Then, a convolutional neural network is designed to identify potentially hazardous areas and detect the early stages of wildfire spots. The detection method is based on the processed images and geographic locations as well as measurements of thermal anomalies, smoke, and unusual variations of regional atmospheric conditions. The effectiveness of the surveillance system is examined through several case studies using numerical simulations. [less ▲]

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See detailSMASCH: Facilitating multi-appointment scheduling in longitudinal clinical research studies and care programs
Vega Moreno, Carlos Gonzalo UL; Gawron, Piotr UL; Lebioda, Jacek et al

Poster (2022, September 20)

Longitudinal clinical research studies require conducting various assessments over long periods of time. Such assessments comprise numerous stages, requiring different resources defined by ... [more ▼]

Longitudinal clinical research studies require conducting various assessments over long periods of time. Such assessments comprise numerous stages, requiring different resources defined by multidisciplinary research staff and aligned with available infrastructure and equipment, altogether constrained by time. While it is possible to manage the allocation of resources manually, it is complex and error-prone. Efficient multi-appointment scheduling is essential to assist clinical teams, ensuring high participant retention and producing successful clinical studies, directly impacting patient throughput and satisfaction. We present Smart Scheduling (SMASCH) system [1], a web application for multi-appointment scheduling management aiming to reduce times, optimise resources and secure personal identifiable information. SMASCH facilitates clinical research and integrated care programs in Luxembourg, providing features to better manage multi-appointment scheduling problems (MASPs) characteristic of longitudinal clinical research studies and speed up management tasks. It is present in multiple clinical research and integrated care programs in Luxembourg since 2017, including Dementia Prevention Program, the study for Mild Cognitive Impairment and gut microbiome, and the National Centre of Excellence in Research on Parkinson’s disease [2] which encompasses the study for REM sleep behaviour disorder and the Luxembourg Parkinson’s Study. SMASCH is a free and open-source solution available both as a Linux package and Docker image. [less ▲]

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See detailHardware-in-the-loop Proximity Operations in Cislunar Space
Muralidharan, Vivek UL; Makhdoomi, Mohatashem Reyaz UL; Barad, Kuldeep Rambhai UL et al

Scientific Conference (2022, September 20)

Space missions to Near Rectilinear Halo Orbits (NRHOs) in the Earth-Moon system are upcoming. A rendezvous technique in the cislunar space is proposed in this investigation, one that leverages coupled ... [more ▼]

Space missions to Near Rectilinear Halo Orbits (NRHOs) in the Earth-Moon system are upcoming. A rendezvous technique in the cislunar space is proposed in this investigation, one that leverages coupled orbit and attitude dynamics in the Circular Restricted Three-body Problem (CR3BP). An autonomous Guidance, Navigation and Control (GNC) technique is demonstrated in which a chaser spacecraft approaches a target spacecraft in the southern 9:2 synodic-resonant L2 Near Rectilinear Halo Orbit (NRHO), one that currently serves as the baseline for NASA's Gateway. A two-layer control approach is contemplated. First, a nonlinear optimal controller identifies an appropriate baseline rendezvous path, both in position and orientation. As the spacecraft progresses along the pre-computed baseline path, optical sensors measure the relative pose of the chaser relative to the target. A Kalman filter processes these observations and offers precise state estimates. A linear controller compensates for any deviations identified from the predetermined rendezvous path. The efficacy of the GNC technique is tested by considering a complex scenario in which the rendezvous operation is conducted with a non-cooperative tumbling target. Hardware-in-the-loop laboratory experiments are conducted as proof-of-concept to validate the guidance algorithm, with observations supplemented by optical navigation techniques. [less ▲]

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See detailMachine learning applied to higher order functional representations of omics data reveals biological pathways associated with Parkinson‘s Disease
Gómez de Lope, Elisa UL; Glaab, Enrico UL

Poster (2022, September 18)

Background: Despite the increasing prevalence of Parkinson’s Disease (PD) and research efforts to understand its underlying molecular pathogenesis, early diagnosis of PD remains a challenge. Machine ... [more ▼]

Background: Despite the increasing prevalence of Parkinson’s Disease (PD) and research efforts to understand its underlying molecular pathogenesis, early diagnosis of PD remains a challenge. Machine learning analysis of blood-based omics data is a promising non-invasive approach to finding molecular fingerprints associated with PD that may enable an early and accurate diagnosis. Description: We applied several machine learning classification methods to public omics data from PD case/control studies. We used aggregation statistics and Pathifier’s pathway deregulation scores to generate higher order functional representations of the data such as pathway-level features. The models’ performance and most relevant predictive features were compared with individual feature level predictors. The resulting diagnostic models from individual features and Pathifier’s pathway deregulation scores achieve significant Area Under the Curve (AUC, a receiver operating characteristic curve) scores for both cross-validation and external testing. Furthermore, we identify plausible biological pathways associated with PD diagnosis. Conclusions: We have successfully built machine learning models at pathway-level and single-feature level to study blood-based omics data for PD diagnosis. Plausible biological pathway associations were identified. Furthermore, we show that pathway deregulation scores can serve as robust and biologically interpretable predictors for PD. [less ▲]

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See detailZum (vermeintlichen) Verschwinden des Reparierens seit den 1970er Jahren
Krebs, Stefan UL

Scientific Conference (2022, September 15)

In der Technikgeschichte wird oftmals angenommen, dass die industrielle Massenfertigung und die Herausbildung der so genannten Wegwerfgesellschaft zu einem Rückgang bzw. Verschwinden des Reparierens von ... [more ▼]

In der Technikgeschichte wird oftmals angenommen, dass die industrielle Massenfertigung und die Herausbildung der so genannten Wegwerfgesellschaft zu einem Rückgang bzw. Verschwinden des Reparierens von Konsumgütern geführt haben. In „Shock of the Old“ spricht David Edgerton z.B. davon, dass sich aufgrund der gesunkenen Anschaffungspreise, das Reparieren einfacher Haushaltsgeräte nicht mehr lohne. Das Hauptargument dieser These verweist also auf das sich seit der Vormoderne wandelnde Verhältnis von Personal- und Materialkosten, das letztlich den Neuerwerb von Konsumgütern günstiger gemacht habe, als die Reparatur gebrauchter Güter. Während der Begriff der Wegwerfgesellschaft bis in die 1950er Jahre zurückreicht, werden für westliche Industriegesellschaften vor allem die 1970er und 80er Jahre als Wendepunkte im Verhältnis von Neuanschaffungs- zu Reparaturkosten beschrieben. Ausgangspunkt für den Vortrag sind Zahlen der Luxemburger Statistikbehörde Statec, die zeigen, dass der Reparatursektor in Luxemburg in den 1980er Jahren einerseits zwar in Bewegung, andererseits keineswegs im Verschwinden war. Ausgehend von einer eingehenderen Betrachtung der verfügbaren Statistiken beschreibt der Vortrag die Veränderungen des Luxemburger Reparatursektors und diskutiert daran die These des vermeintlichen Verschwindens des Reparierens von Konsumgütern. [less ▲]

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See detailA Communal Struggle: Team-Teaching at the University of Luxembourg
Rivas, Salvador UL; Bes Izuel, Maria Asuncion UL; Zutavern, Jan UL

Scientific Conference (2022, September 15)

INTRODUCTION Team-teaching, also known as collaborative-teaching, co-teaching and pair-lecturing has been practiced for ages (Buckley 2000). It is generally described as a positive pedagogical practice ... [more ▼]

INTRODUCTION Team-teaching, also known as collaborative-teaching, co-teaching and pair-lecturing has been practiced for ages (Buckley 2000). It is generally described as a positive pedagogical practice that can both enhance learning among students and the experience of teaching among instructors (Plank 2011, 2014). While it is acknowledged that team-teaching is not simple and requires great coordination among instructors, it is presented in gleaming terms for both instructors and students alike. More recent work highlights an increased necessity for collaborative-teaching due to the growing complexity in higher education combined with dwindling resources (Minett-Smith and Davis 2020), or as a deliberate cost-saving measure (Liebel et al. 2017). Yet, little quantitative evidence can be found in the literature showing the positive efficacy of this methodology, relative to Student Evaluation Teaching (SET) measures (for exception see: Carpenter et al. 2007). Thus, this study aims to answer: 1) how prevalent is team-teaching; 2) what are the most common team compositions (number of instructors, gender, instructor status and seniority); 3) are there any significant differences in SET scores relative to differences in composition; and 4) what can we learn from the open-text feedback to help us understand, or contextualize, any quantitative differences found between solo- versus team-taught courses? DATA & METHODS To address our research questions and investigate the contours of team teaching in the Faculty of Humanities, Education and Social Sciences (FHSE) at the University of Luxembourg, we use SET data (course feedback), as an indirect measure of quality of education (Marsh 2007). We use descriptive statistics and regression analysis to examine the quantitative feedback for a total of 2908 courses collected over eight semesters (Winter semester 2015-Summer semester 2019). We compliment these results with content analysis of open-text comments that help us understand and contextualize the quantitative findings. PRELIMINARY RESULTS While course feedback data does not directly measure the quality of learning experienced by students (i.e., whether students learn better in team-taught courses vs. solo instructor courses), it does however shed light on the general sentiment experienced and reported by participating students. Preliminary analyses indicate that approximately 30% of courses are team-taught (60% with two-person teams and 40% with teams of 3 and 4+ instructors). Furthermore, we found that, on average, team-taught courses receive significantly lower ratings from students than solo instructor courses. In the remainder of this article, we analyse this basic finding and discuss the implications for team teaching. [less ▲]

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See detailA fictitious diary of a schoolgirl in 1928
Harnoncourt, Julia UL; Steiner, Benjamin

Scientific Conference (2022, September 15)

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See detailapi or archives? tormented ways to transform tweets into historical sources
Clavert, Frédéric UL

Scientific Conference (2022, September 15)

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See detail3D printed mathematics visualisations by STEAM teachers
Ulbrich, Eva; Tejera, Mathias; Haas, Ben et al

Scientific Conference (2022, September 12)

Visualising abstract concepts such as for example geometrical objects in mathematics can be a valuable support for learners. Visualisation, however, is a process involving several steps that influence ... [more ▼]

Visualising abstract concepts such as for example geometrical objects in mathematics can be a valuable support for learners. Visualisation, however, is a process involving several steps that influence each other. Duval (1998) uses steps connecting reasoning by an explanation or proof to a construction step involving tools creating a visualisation to a production of a visual representation leading to new insights about a geometrical object. Vágová (2020) argues that visualising geometrical objects needs the ability to create, manipulate, and transform mental images by an internal and an external representation which both require information about the spatial arrangement. 3D modelled and then visualised geometrical objects can support the development and train visualisation skills. Steps of visualisation processes require visuospatial competencies and are also important for other subjects in Science, Technology, Engineering, Arts and Mathematics (STEAM) education (Ng 2017). Being able to understand representations and their spatial rotations, transitions between 2D and 3D and being able to manipulate representations are valuable for STEAM related subjects (Kok 2020). Martin-Dorta et al. (2008) says that spatial abilities can be improved using real and computer-aided models. 3D printing can therefore be an interesting activity as it also combines the mentioned steps in a mathematical modelling way. This approach was used in a beginners course for pre-service mathematics teachers and some of them chose to create mathematical proofs as visualisation. We will look at 3D printed objects, which concepts they visualise and what teachers' ideas behind visualisations were. [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 detailEntre chien et loup de Christiane Jatahy (2021-2022) : un théâtre au présent, témoin des formes contemporaines de fascisme
Deregnoncourt, Marine UL

Scientific Conference (2022, September 09)

Nous entendons nous intéresser à la rencontre qui s’est déroulée, le lundi 7 mars 2022 à 20h au cinéma Mk2 Nation (Paris, 12ème), entre la mettrice en scène brésilienne, Christiane Jatahy, la philosophe ... [more ▼]

Nous entendons nous intéresser à la rencontre qui s’est déroulée, le lundi 7 mars 2022 à 20h au cinéma Mk2 Nation (Paris, 12ème), entre la mettrice en scène brésilienne, Christiane Jatahy, la philosophe Marylin Maeso, autrice de La petite fabrique de l’inhumain et la psychanalyste Clotilde Leguil, venant de publier Céder n’est pas consentir. Cet échange fut dédié à Entre chien et loup, dernier spectacle en date, voulu par l’artiste carioca précitée — à la notoriété grandissante en Europe depuis près de vingt ans — d’après le scénario du film de Lars von Trier : Dogville avec Nicole Kidman dans le rôle-titre de Grace. Cet événement liminaire nous servira à démontrer, à terme, combien cette création se révèle être un théâtre éminemment ancré dans le présent, témoignant de toutes les formes contemporaines de fascisme, par le truchement, précisément, du personnage de Grace, devenu, pour les besoins de la mise en scène, Gracia, jeune femme d’origine brésilienne, interprétée par Julia Bernat, actrice fétiche de Christiane Jatahy grâce à laquelle elle peut faire pleinement entendre sa propre voix d’artiste politiquement engagée. [less ▲]

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See detailAutomatic Classification of Peer Review Recommendation
Kozlowski, Diego UL; Boothby, Clara; Pei-Ying, Chen et al

Poster (2022, September 08)

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See detailOptimal industrial flexibility scheduling based on generic data format
Bahmani, Ramin UL; van Stiphoudt, Christine UL; Potenciano Menci, Sergio UL et al

in Energy Informatics (2022, September 07), 5

The energy transition into a modern power system requires energy flexibility. Demand Response (DR) is one promising option for providing this flexibility. With the highest share of final energy ... [more ▼]

The energy transition into a modern power system requires energy flexibility. Demand Response (DR) is one promising option for providing this flexibility. With the highest share of final energy consumption, the industry has the potential to offer DR and contribute to the energy transition by adjusting its energy demand. This paper proposes a mathematical optimization model that uses a generic data model for flexibility description. The optimization model supports industrial companies to select when (i.e., at which time), where (i.e., in which market), and how (i.e., the schedule) they should market their flexibility potential to optimize profit. We evaluate the optimization model under several synthetic use cases developed upon the learnings over several workshops and bilateral discussions with industrial partners from the paper and aluminum industry. The results of the optimization model evaluation suggest the model can fulfill its purpose under different use cases even with complex use cases such as various loads and storages. However, the optimization model computation time grows as the complexity of use cases grows. [less ▲]

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See detailTranslanguaging pedagogy and creative activism for early education in multilingual Luxembourg
Aleksic, Gabrijela UL

Scientific Conference (2022, September 07)

Luxembourg is a highly linguistically and culturally diverse country. In early education, there are 64 % of four-year old children who not speak Luxembourgish at home (MENJE, 2018). From 2017 ... [more ▼]

Luxembourg is a highly linguistically and culturally diverse country. In early education, there are 64 % of four-year old children who not speak Luxembourgish at home (MENJE, 2018). From 2017, multilingual early education is mandatory, which obliges teachers to develop children’s Luxembourgish, familiarizing them with French, and valuing their home languages. Therefore, the present project aimed to: (1) offer an 18-hours professional development (PD) course in translanguaging pedagogy to 40 teachers over 6 months, (2) strengthen home-school collaboration, and (3) support children’s linguistic, socio-emotional, and cognitive development and engagement in the classroom. The results from teacher questionnaires, focus groups, and interviews, showed that there was some positive change regarding the attitudes towards children’s home languages. The interviews with 17 parents indicated that there was a need for more home-school collaboration. The tests in early literacy and numeracy with 23 preschool children over one year, identified that children performed higher in their home languages. The video observations showed that when the teachers used children’s languages in the classroom, this impacted positively their well-being. Following the principles of creative activism, the author produced: (1) the website with over 100 practical activities on how teachers can involve children’s languages and families, (2) the illustrated book Sumak for parents, showing difficulties with integration in a new country, and (3) the illustrated book, Mara’s song for preschool children, showing how Mara finds her way in the new classroom. [less ▲]

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See detailAbstracts of the 11th DACH+ Conference on Energy Informatics (S53-Taxonomy of Local Flexibility Markets)
Potenciano Menci, Sergio UL

in Energy Informatics (2022, September 07), 5

Flexibility has risen as a potential solution and complement for system operators’ current and future problems (e.g., congestion, voltage) caused by integrating distributed renewable resources (e.g., wind ... [more ▼]

Flexibility has risen as a potential solution and complement for system operators’ current and future problems (e.g., congestion, voltage) caused by integrating distributed renewable resources (e.g., wind, solar) and electric vehicles. In parallel, local flexibility markets (LFM) emerge as a possible smart grid solution to bridge between flexibility-seeking customers and flexibility-offering customers in localized areas. Nevertheless, there is no unique, standard, or simple solution to tackle all the problems system operators and other energy actors face. Therefore, many local flexibility market concepts, initiatives (projects), and companies have developed various solutions over the last few years. At the same time, they increased the complexity of the topic. Thus, this research paper aims to describe several local flexibility market concepts, initiatives (projects), and companies in Europe. To do so, we propose a taxonomy derived from LFMs descriptions. We use the taxonomy-building research method proposed by [1] to develop our taxonomy. Moreover, we use the smart grid architecture model (SGAM) as a structural and foundation guideline. Given the numerous and diverse LFM solutions, we delimit the taxonomy by considering solutions focused on congestion management on medium and low voltage (meta-characteristic). [less ▲]

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See detail1848 und die Folgen. Geburtsstunde der Laienmusik in Luxemburg
Sagrillo, Damien François UL

Scientific Conference (2022, September 06)

Im Jahr 1789 hat Luxemburg als selbstständiger und unabhängiger Staat noch nicht existiert. Es bedurfte des Wiener Kongresses (1815) und der belgischen Revolution (1830), um aus Luxemburg ein souveräner ... [more ▼]

Im Jahr 1789 hat Luxemburg als selbstständiger und unabhängiger Staat noch nicht existiert. Es bedurfte des Wiener Kongresses (1815) und der belgischen Revolution (1830), um aus Luxemburg ein souveräner Staat werden zu lassen. Bürgerliche Freiheiten wurden den Luxemburgern allerdings erst unter König-Großherzog Wilhelm II zugestanden. Mit dem Versammlungsrecht wurde der Bevölkerung auch das Vereinigungsrecht gewährt. Das Jahr 1848 bedeutet den Startpunkt und eine erste Wegmarke im Werden der Laienmusik im Großherzogtum. Im Jahr 1940 kam es mit der deutschen Besetzung zu einem abrupten Bruch einer Freiheit, die den Luxemburgern in fast einem Jahrhundert in Fleisch und Blut übergegangen zu sein schien. Der Neubeginn ab dem Jahr 1944 bedeutete eine weitere Wegmarke im Sinne von kultureller Betätigung in einer freiheitlichen Grundordnung. Im Diskurs um weitere Wegmarken sind keine politische, sondern eher soziale, pädagogische und technologische Umwälzungen ins Visier zu nehmen. [less ▲]

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See detailAnalysis and comparison of gait impairments in patients with Parkinson’s disease and normal pressure hydrocephalus using wearable sensors and machine learning algorithms
Magni, Stefano UL; Bremm, René Peter UL; Lecossois, Sylvie et al

Scientific Conference (2022, September 05)

Objectives. Gait impairments in patients with Parkinson’s disease (PD) and normal pressure hydrocephalus (NPH) are visually assessed by movement disorders experts for diagnoses and to decide on ... [more ▼]

Objectives. Gait impairments in patients with Parkinson’s disease (PD) and normal pressure hydrocephalus (NPH) are visually assessed by movement disorders experts for diagnoses and to decide on pharmaceutical and surgical interventions. Despite standardised tests and clinicians’ expertise, such approaches entail a considerable level of subjectivity. The recent development of wearable sensors and machine learning offers complementary approaches providing more objective, quantitative assessments of gait impairments. We aim to employ the data gathered from an inertial measurement unit synchronized with a novel foot pressure sensor embedded in the patient’s shoes to characterize gait impairments. We focus on distinguishing PD from NPH and on assessing gait impairment before and after surgical intervention. Methods. A cohort of 10 PD and 10 NPH patients was assembled and patients performed standardised walking tests. Measurements were performed employing wearable sensors comprising a three-axes gyroscope, a three-axes accelerometer and eight pressure sensors embedded in each patient’s shoe. To analyse the generated data, existing algorithms were implemented and adapted. These allow to compute gait cycle parameters such as step time and metrics characterizing the swing and stance phases. Machine learning algorithms where employed to identify major changes in gait cycle parameters between the two groups of patients, and for individual patients before and after surgical intervention as DBS implantation in PD and Shunt implantation in NPH. Results. The gait impairments of both disease groups were measured and quantified. An algorithm to extract gait cycle parameters from sensors was implemented, tested and employed on such patients. Gait cycle parameters within and between the groups of PD and NPH patients were compared, assessing what gait cycle parameters allow to distinguish between these groups. Gait cycle impairments of patients before and after surgery were compared, assessing the effect of DBS or Shunt implantation and which gait cycle parameters allow to monitor symptoms improvement. Conclusions. Wearable sensors measuring pressure, combined with gait cycle parameters extraction and machine learning algorithms, have a great potential for objective evaluation of gait impairment. In particular, they allow to characterize what differentiate such impairments between PD and NPH patients, and what allow to assess motor symptoms improvement after surgery. [less ▲]

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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 detailAn Overview of Channel Models for NGSO Satellites
Monzon Baeza, Victor UL; Lagunas, Eva UL; Al-Hraishawi, Hayder UL et al

Scientific Conference (2022, September)

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See detail5G-NTN GEO-based In-Lab Demonstrator using OpenAirInterface5G
Kumar, Sumit UL; Abdalla, Abdelrahman UL; Kodheli, Oltjon UL et al

in 11th Advanced Satellite Multimedia Conference (2022, September)

The integration of 5G with Non-Terrestrial Network (NTN) components is going through a series of technological advancements and soon satellites will be a part of the 5G ecosystem. Early demonstrators ... [more ▼]

The integration of 5G with Non-Terrestrial Network (NTN) components is going through a series of technological advancements and soon satellites will be a part of the 5G ecosystem. Early demonstrators, especially based on open-source implementations, are essential to support further research. In this work, we discuss the ongoing activities and developments related to the project 5G-Enabled Ground Segment Technologies OverThe-Air Demonstrator (5G-GoA) which has been funded under the ESA-ARTES program. The vision of 5G-GoA is developing and implementing suitable modifications in the 5G New Radio (NR) standard for enabling direct radio access to 5G services using a transparent GEO satellite. For this purpose, we have used OpenAirInterface(OAI) which is a Software Defined Radio (SDR) based open-source implementation of the 5G-NR protocol stack. We adapted it to address the challenges caused by the excessive round-trip delay in GEO satellites. Our solutions encompass all the layers of the 5G protocol stack: The physical layer (e.g. synchronization) up to upper layer implementations (e.g. timers and random-access procedure) of the Radio Access Network. Our modifications comply with the specifications mentioned for 5GNTN in the recently frozen 3GPP Release-17. An end-to-end demonstrator has been developed for in-lab validation over a satellite channel emulator prior to over-the-satellite testing. Our initial experiments show promising results and the feasibility of direct access to 5G services through transparent GEO satellites. [less ▲]

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See detailUpdate: Besteuerung der digitalen Wirtschaft (International und Europäische Union)
Sinnig, Julia UL

in Taeger, Jürgen (Ed.) Tagungsband 2022: Daten, Plattformen und KI als Dreiklang unserer Zeit (2022, September)

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See detailThe Impact Of Distributed Data Preprocessing On Automotive Data Streams
Tawakuli, Amal UL; Engel, Thomas UL

in 2022 IEEE 96th Vehicular Technology Conference: (VTC2022-Fall) (2022, September)

Vehicles have transformed into sophisticated com- puting machines that not only serve the objective of transporta- tion from point A to point B but serve other objectives including improved experience ... [more ▼]

Vehicles have transformed into sophisticated com- puting machines that not only serve the objective of transporta- tion from point A to point B but serve other objectives including improved experience, safer journey, automated and more efficient and sustainable transportation. With such sophistication comes complex applications and enormous volumes of data generated from diverse types of vehicle sensors and components. Automotive data is not sedentary but moves from the edge (the vehicle) to the cloud (e.g., infrastructure of the vehicle manufacturers, national highway agencies, insurance companies, etc.). The exponential increase in data volume and variety generated in modern vehicles far exceeds the rate of infrastructure scaling and expansion. To mitigate this challenge, the computational and storage capacities of vehicle components can be leveraged to perform in-vehicle operations on the data to either prepare and transform (prepro- cess) the data or extract information from (process) the data. This paper focuses on distributing data preprocessing to the vehicle and highlights the benefits and impact of the distribution including on the consumption of resources (e.g., energy). [less ▲]

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See detailDesign of an experimental platform for gait analysis with ActiSense and StereoPi
Leer, Alexandra; Santa Cruz, Beatriz Garcia; Hertel, Frank et al

in Current Directions in Biomedical Engineering (2022, September), 8(2), 572-575

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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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