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See detailAutomotive Squint-forward-looking SAR: High Resolution and Early Warning
Hu, Ruizhi UL; Mysore Rama Rao, Bhavani Shankar UL; Murtada, Ahmed Abdelnaser Elsayed UL et al

in IEEE Journal of Selected Topics in Signal Processing (2021)

Forward-looking automotive radars can sense long-distant targets to enable early warning, but the lateral resolution is limited. Synthetic aperture radar (SAR) techniques can achieve very high azimuth ... [more ▼]

Forward-looking automotive radars can sense long-distant targets to enable early warning, but the lateral resolution is limited. Synthetic aperture radar (SAR) techniques can achieve very high azimuth resolution but cannot resolve targets in the forward direction. As a trade-off, squint-forward-looking SAR (SFL-SAR) can perform 2D imaging on a distant area squint to the moving direction, providing both high resolution and early warning. In this paper, we analyzed and derived the constraints of automotive SFL-SAR to satisfy both the required resolution and braking distance. Simulations and imaging results verified the analysis. [less ▲]

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See detailAccess to housing and education for children in migration: challenges and good practices
Sommarribas, Adolfo UL

Scientific Conference (2021, March 10)

This presentation focus on the access to housing and education for children in migration, the challenges confronted and the good practices detected.

Detailed reference viewed: 113 (0 UL)
See detailDigital history and the politics of digitization
Zaagsma, Gerben UL

Scientific Conference (2021, March 10)

This paper addresses the question of the politics of (cultural heritage) digitisation and its consequences for historical research. To put it simply, it discusses the question of why, where and how we can ... [more ▼]

This paper addresses the question of the politics of (cultural heritage) digitisation and its consequences for historical research. To put it simply, it discusses the question of why, where and how we can access what we can access. The online documentary record affects historical research and we need to understand how and in what ways our online evidentiary basis is constituted and might affect our research. [less ▲]

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See detailWomen and ICT: A Time Travel
Schafer, Valerie UL

Presentation (2021, March 08)

Presentation of the workshop : To mark the International Day of Women Rights, the University of Luxembourg is organizing an online workshop on Women in Computing. ICT is today one of the most gendered ... [more ▼]

Presentation of the workshop : To mark the International Day of Women Rights, the University of Luxembourg is organizing an online workshop on Women in Computing. ICT is today one of the most gendered-divided fields. Gendered stereotypes suggesting that men are more interested in ICT are still active in shaping attitudes. However, this inequality has only started in the 80s. For instance, by 1943, in the USA, almost all people employed in computing were women. It is was common to believe that "programming requires lots of patience, persistence and a capacity for detail and those are traits that many girls have". The speakers of this workshop will shed light on the historical role of women in computing to help us understand how to improve gender inequality in ICT. [less ▲]

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See detailEl duende, quand une technique propre au flamenco s’impose sur la scène de théâtre : Partage de midi de Paul Claudel (mise en scène d’Yves Beaunesne)
Deregnoncourt, Marine UL

in Deregnoncourt, Marine; Rameau, Corinne (Eds.) Le flamenco dans tous ses états : de la scène à la page, du pas à l’image (2021, March 08)

Pour tenter de correspondre au mieux au propos de cette journée d’études intitulée : « Le flamenco dans tous ses états : de la scène à la page, du pas à l’image », nous nous proposons d’analyser comment ... [more ▼]

Pour tenter de correspondre au mieux au propos de cette journée d’études intitulée : « Le flamenco dans tous ses états : de la scène à la page, du pas à l’image », nous nous proposons d’analyser comment le duende, technique propre au flamenco, peut être envisagé comme une clé de lecture opérante pour aborder la mise en scène d’Yves Beaunesne de Partage de midi de Paul Claudel (Comédie – Française, 2007 et Théâtre Marigny, 2009) et plus précisément de la scène d’amour (Acte II, Scène 2). En effet, lors de cette scène, Marina Hands et Éric Ruf, interprètes respectifs d’Ysé et de Mesa (protagonistes phares du drame claudélien) se livrent à une danse contemporaine caractérisée par un tombé au sol et une relève et comparable à une lutte, un break1, une transe et « un véritable cri du corps entier »2. Comment cela se manifeste-t-il sur scène ? C’est précisément à cette problématique que notre communication entend se consacrer. Pour ce faire, notre réflexion se divisera en deux parties. La première sera davantage théorique et tentera de définir ce qu’est le duende. La seconde s’axera, quant à elle, sur le spectacle précité et concernera plus spécifiquement la danse contemporaine exécutée par ces deux acteurs. [less ▲]

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See detailEnd-to-end Precoding Validation over a Live GEO Satellite Forward Link
Krivochiza, Jevgenij UL; Merlano Duncan, Juan Carlos UL; Querol, Jorge UL et al

in IEEE Access (2021)

In this paper we demonstrate end-to-end precoded multi-user multiple-input singleoutput (MU-MISO) communications over a live GEO satellite link. Precoded communications enable full frequency reuse (FFR ... [more ▼]

In this paper we demonstrate end-to-end precoded multi-user multiple-input singleoutput (MU-MISO) communications over a live GEO satellite link. Precoded communications enable full frequency reuse (FFR) schemes in satellite communications (SATCOM) to achieve broader service availability and higher spectrum efficiency than with the conventional four-color (4CR) and twocolor (2CR) reuse approaches. In this scope, we develop an over-the-air test-bed for end-to-end precoding validations.We use an actual multi-beam satellite to transmit and receive precoded signals using the DVB-S2X standard based gateway and user terminals. The developed system is capable of end-to-end real-time communications over the satellite link including channel measurements and precompensation. It is shown, that by successfully canceling inter-user interference in the actual satellite FFR link precoding brings gains in terms of enhanced SINR and increased system goodput. [less ▲]

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See detailThe Western European Borderlands. Overview of Possible Case-Studies
Venken, Machteld UL

Scientific Conference (2021, March 05)

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See detailConstructing effective and efficient EAP curricula
Deroey, Katrien UL

Presentation (2021, March 04)

In this talk I will sketch the development of an EAP curriculum at the University of Luxembourg Language Centre that takes into account multilingualism, needs analysis, insights into EAP teaching and ... [more ▼]

In this talk I will sketch the development of an EAP curriculum at the University of Luxembourg Language Centre that takes into account multilingualism, needs analysis, insights into EAP teaching and materials, discussions with stakeholders, and human resources. I will argue for an EAP curriculum approach that trains a set of core skills and enables discipline-specific genre and language learning through awareness-raising activities and corpus search tools. In this view, English for Specific Academic Purposes is not the teaching of disciplinary vocabulary. Instead, teachers use their EAP expertise to ascertain disciplinary needs, compose or evaluate materials, set tasks in line with disciplinary activities, and –importantly- provide the skills and tools to continue (discipline-specific) learning beyond the course. I will draw on examples of EAP course design from my own practice as well as on findings from my published research into EAP coursebook authenticity and multilingual course design. [less ▲]

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See detailCross-Linking Ligation and Sequencing of Hybrids (qCLASH) Reveals an Unpredicted miRNA Targetome in Melanoma Cells
Kozar, Ines UL; Philippidou, Demetra UL; Margue, Christiane UL et al

in Cancers (2021)

MicroRNAs are key post-transcriptional gene regulators often displaying aberrant expression patterns in cancer. As microRNAs are promising disease-associated biomarkers and modulators of responsiveness to ... [more ▼]

MicroRNAs are key post-transcriptional gene regulators often displaying aberrant expression patterns in cancer. As microRNAs are promising disease-associated biomarkers and modulators of responsiveness to anti-cancer therapies, a solid understanding of their targetome is crucial. Despite enormous research efforts, the success rates of available tools to reliably predict microRNAs (miRNA)-target interactions remains limited. To investigate the disease-associated miRNA targetome, we have applied modified cross-linking ligation and sequencing of hybrids (qCLASH) to BRAF-mutant melanoma cells. The resulting RNA-RNA hybrid molecules provide a comprehensive and unbiased snapshot of direct miRNA-target interactions. The regulatory effects on selected miRNA target genes in predicted vs. non-predicted binding regions was validated by miRNA mimic experiments. Most miRNA–target interactions deviate from the central dogma of miRNA targeting up to 60% interactions occur via non-canonical seed pairing with a strong contribution of the 3′ miRNA sequence, and over 50% display a clear bias towards the coding sequence of mRNAs. miRNAs targeting the coding sequence can directly reduce gene expression (miR-34a/CD68), while the majority of non-canonical miRNA interactions appear to have roles beyond target gene suppression (miR-100/AXL). Additionally, non-mRNA targets of miRNAs (lncRNAs) whose interactions mainly occur via non-canonical binding were identified in melanoma. This first application of CLASH sequencing to cancer cells identified over 8 K distinct miRNA–target interactions in melanoma cells. Our data highlight the importance non-canonical interactions, revealing further layers of complexity of post-transcriptional gene regulation in melanoma, thus expanding the pool of miRNA–target interactions, which have so far been omitted in the cancer field. [less ▲]

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See detailAdaptively Secure Laconic Function Evaluation for NC1
Agrawal, Shweta; Rosie, Razvan UL

E-print/Working paper (2021)

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See detailElectron hydrodynamics of anomalous Hall materials
Hasdeo, Eddwi Hesky UL; Ekström, Carl Johan Ingvar UL; Idrisov, Edvin UL et al

in Physical Review. B (2021), 103(12), 125106

We study two-dimensional electron systems in the hydrodynamic regime. We show that a geometrical Berry curvature modifies the effective Navier-Stokes equation for viscous electron flow in topological ... [more ▼]

We study two-dimensional electron systems in the hydrodynamic regime. We show that a geometrical Berry curvature modifies the effective Navier-Stokes equation for viscous electron flow in topological materials. For small electric fields, the Hall current becomes negligible compared to the viscous longitudinal current. In this regime, we highlight an unconventional Poiseuille flow with an asymmetric profile and a deviation of the maximum of the current from the center of the system. In a two-dimensional infinite geometry, the Berry curvature leads to current whirlpools and an asymmetry of potential profile. This phenomenon can be probed by measuring the asymmetric non-local resistance profile. [less ▲]

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See detailNanoscale Phononic Analog of the Ranque-Hilsch Vortex Tube
Medrano Sandonas, Leonardo UL; Rodríguez Méndez, Álvaro; Gutierrez, Rafael et al

in Physical Review Applied (2021), 15(034008),

Thermal management is a current global challenge that must be addressed exhaustively. We propose the design of a nanoscale phononic analog of the Ranque-Hilsch vortex tube in which heat flowing at a given ... [more ▼]

Thermal management is a current global challenge that must be addressed exhaustively. We propose the design of a nanoscale phononic analog of the Ranque-Hilsch vortex tube in which heat flowing at a given temperature is split into two different streams going to the two ends of the device, inducing a temperature asymmetry. Our nanoscale prototype consists of two carbon nanotubes (capped and open) connected by molecular chains. The results show that the structural asymmetry in the contact regions is the key factor for producing the flux asymmetry and, hence, the induced temperature-bias effect. The effect can be controlled by tuning the thermal-equilibration temperature, the number of chains, and the chain length. Deposition on a substrate adds another variable to the manipulation of the flux asymmetry but the effect vanishes at very large substrate temperatures. Our study yields insights into the thermal management in nanoscale materials, especially the crucial issue of whether the thermal asymmetry can survive phonon scattering over relatively long distances, and thus provides a starting point for the design of a nanoscale phononic analog of the Ranque-Hilsch vortex tube. [less ▲]

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See detailOpenMP optimisation of the eXtended Discrete Element Method (XDEM)
Ojeda-May, Pedro; Eriksson, Jerry; Rousset, Alban UL et al

Report (2021)

The eXtended Discrete Element Method (XDEM) is an extension of the regular Discrete Element Method (DEM) which is a software for simulating the dynamics of granular material. XDEM extends the regular DEM ... [more ▼]

The eXtended Discrete Element Method (XDEM) is an extension of the regular Discrete Element Method (DEM) which is a software for simulating the dynamics of granular material. XDEM extends the regular DEM method by adding features where both micro and macroscopic observables can be computed simultaneously by coupling different time and length scales. In this sense XDEM belongs the category of multi-scale/multi-physics applications which can be used in realistic simulations. In this whitepaper, we detail the different optimisations done during the preparatory PRACE project to overcome known bottlenecks in the OpenMP implementation of XDEM. We analysed the Conversion, Dynamic, and the combined Dynamics-Conversion modules with Extrae/Paraver and Intel VTune profiling tools in order to find the most expensive functions. The proposed code modifications improved the performance of XDEM by ~17% for the computational expensive Dynamics-Conversion combined modules (with 48 cores, full node). Our analysis was performed in the Marenostrum 4 (MN4) PRACE infrastructure at Barcelona Supercomputing Center (BSC). [less ▲]

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See detailNeutron study of magnetic correlations in rare-earth-free Mn-Bi magnets
Malyeyev, Artem UL; Titov, Ivan; Bender, Philipp et al

in Physical Review Materials (2021), 5

We report the results of an unpolarized small-angle neutron scattering (SANS) study on Mn-Bi-based rare-earth-free permanent magnets. The magnetic SANS cross section is dominated by long-wavelength ... [more ▼]

We report the results of an unpolarized small-angle neutron scattering (SANS) study on Mn-Bi-based rare-earth-free permanent magnets. The magnetic SANS cross section is dominated by long-wavelength transversal magnetization fluctuations and has been analyzed in terms of the Guinier-Porod model and the distance distribution function. This provides the radius of gyration which, in the remanent state, ranges between about $220-240 \, \mathrm{nm}$ for the three different alloy compositions investigated. Moreover, computation of the distance distribution function in conjunction with results for the so-called $s$-parameter obtained from the Guinier-Porod model indicate that the magnetic scattering of a Mn$_{45}$Bi$_{55}$ sample has its origin in slightly shape-anisotropic structures. [less ▲]

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See detailExploring the History of Digital History
Zaagsma, Gerben UL

Scientific Conference (2021, March 01)

This short paper will present the first results, and outline my new project which investigates the early trajectories of history and computing and focuses on the networks of computing historians in the ... [more ▼]

This short paper will present the first results, and outline my new project which investigates the early trajectories of history and computing and focuses on the networks of computing historians in the pre-PC and early PC period. [less ▲]

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See detailEfficient Federated Learning Algorithm for Resource Allocation in Wireless IoT Networks
Nguyen, van Dinh UL; Sharma, Shree Krishna UL; Vu, Thang Xuan UL et al

in IEEE Internet of Things Journal (2021), 8(5), 3394-3409

Federated learning (FL) allows multiple edge computing nodes to jointly build a shared learning model without having to transfer their raw data to a centralized server, thus reducing communication ... [more ▼]

Federated learning (FL) allows multiple edge computing nodes to jointly build a shared learning model without having to transfer their raw data to a centralized server, thus reducing communication overhead. However, FL still faces a number of challenges such as non-iid distributed data and heterogeneity of user equipments (UEs). Enabling a large number of UEs to join the training process in every round raises a potential issue of the heavy global communication burden. To address these issues, we generalize the current state-of-the-art Federated Averaging (FedAvg) by adding a weight-based proximal term to the local loss function. The proposed FL algorithm runs stochastic gradient descent in parallel on a sampled subset of the total UEs with replacement during each global round. We provide a convergence upper bound characterizing the trade-off between convergence rate and global rounds, showing that a small number of active UEs per round still guarantees convergence. Next, we employ the proposed FL algorithm in wireless Internet-of-Things (IoT) networks to minimize either total energy consumption or completion time of FL, where a simple yet efficient path-following algorithm is developed for its solutions. Finally, numerical results on unbalanced datasets are provided to demonstrate the performance improvement and robustness on the convergence rate of the proposed FL algorithm over FedAvg. They also reveal that the proposed algorithm requires much less training time and energy consumption than the FL algorithm with full user participation. These observations advocate the proposed FL algorithm for a paradigm shift in bandwidth- constrained learning wireless IoT networks. [less ▲]

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See detailUrban expansion re-visited
Hesse, Markus UL

in pnd - rethinking planning (2021), 2021(1), 42-54

This paper deals with urban expansion, that is, the growth of cities and inner-urban areas, both inside and outside of the dedicated planning perimeters. My aim is to give a brief overview of how this ... [more ▼]

This paper deals with urban expansion, that is, the growth of cities and inner-urban areas, both inside and outside of the dedicated planning perimeters. My aim is to give a brief overview of how this subject matter can be discussed from a contemporary perspective, with a certain focus on big projects that have evolved in recent decades and are on the rise again. Towards that end, I will situate the subject matter in historical contexts, provide some explanation as to the 1970s and more recent dynamics, and discuss how large-scale urban projects are being implemented. While big projects pursue different ambitions—such as economic, socio-demographic or ecological goals—they are set in place by a kind of managerial urbanism, often prioritise economic gains and thus challenge urban policy and planning. The paper concludes with a call to contextualise the variegated outcomes of new urban projects and to develop appropriate methods for monitoring and assessing urban life in these quarters. [less ▲]

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See detailAccounting for Differences in Income Inequality across Countries: Tax-benefit Policy, Labour Market Structure, Returns and Demographics
Sologon, Denisa UL; van Kerm, Philippe UL; Li, Jinjing et al

in Journal of Economic Inequality (2021), 19

This paper presents a framework for studying international differences in the distribution of household income. Integrating micro-econometric and micro-simulation approaches in a decomposition analysis ... [more ▼]

This paper presents a framework for studying international differences in the distribution of household income. Integrating micro-econometric and micro-simulation approaches in a decomposition analysis, it quantifies the role of tax-benefit systems, employment and occupational structures, labour and financial market returns, and demographic composition in accounting for differences in income inequality across countries. Building upon EUROMOD (the European tax-benefit calculator) and its harmonised datasets, the model is portable and can be implemented for cross-country comparisons between any participating country. An application to the UK and Ireland—two countries that have much in common while displaying different levels of inequality—shows that differences in tax benefit rules between the two countries account for roughly half of the observed difference in disposable household income inequality. Demographic differences play negligible roles. The Irish tax-benefit system is more redistributive than UK\textquoterights due to a higher tax progressivity and higher average transfer rates. These are largely attributable to policy parameter differences, but also to differences in pre-tax, pre-transfer income distributions. [less ▲]

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See detailAuswirkungen der COVID-19-Pandemie auf den sozialen Zusammenhalt
Steffgen, Georges UL; Sischka, Philipp UL

in Benoy, Charles (Ed.) COVID-19 - Ein Virus nimmt Einfluss auf unsere Psyche (2021)

Detailed reference viewed: 30 (3 UL)