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See detailAn Agile Approach to Validate a Formal Representation of the GDPR
Bartolini, Cesare UL; Lenzini, Gabriele UL; Santos, Cristiana

in New Frontiers in Artificial Intelligence (in press)

Modelling in a knowledge base of logic formulæ the articles of the GDPR enables a semi-automatic reasoning of the Regulation. To be legally substantiated, it requires that the formulæ express validly the ... [more ▼]

Modelling in a knowledge base of logic formulæ the articles of the GDPR enables a semi-automatic reasoning of the Regulation. To be legally substantiated, it requires that the formulæ express validly the legal meaning of the Regulation's articles. But legal experts are usually not familiar with logic, and this calls for an interdisciplinary validation methodology that bridges the communication gap between formal modelers and legal evaluators. We devise such a validation methodology and exemplify it over a knowledge base of articles of the GDPR translated into Reified I/O (RIO) logic and encoded in LegalRuleML. A pivotal element of the methodology is a human-readable intermediate representation of the logic formulæ that preserves the formulæ's meaning, while rendering it in a readable way to non-experts. After being applied over a use case, we prove that it is possible to retrieve feedback from legal experts about the formal representation of Art. 5.1a and Art. 7.1. What emerges is an agile process to build logic knowledge bases of legal texts, and to support their public trust, which we intend to use for a logic model of the GDPR, called DAPRECO knowledge base. [less ▲]

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See detailOn indefinite sums weighted by periodic sequences
Marichal, Jean-Luc UL

in Results in Mathematics (in press)

For any integer $q\geq 2$ we provide a formula to express indefinite sums of a sequence $(f(n))_{n\geq 0}$ weighted by $q$-periodic sequences in terms of indefinite sums of sequences $(f(qn+p))_{n\geq 0 ... [more ▼]

For any integer $q\geq 2$ we provide a formula to express indefinite sums of a sequence $(f(n))_{n\geq 0}$ weighted by $q$-periodic sequences in terms of indefinite sums of sequences $(f(qn+p))_{n\geq 0}$, where $p\in\{0,\ldots,q-1\}$. When explicit expressions for the latter sums are available, this formula immediately provides explicit expressions for the former sums. We also illustrate this formula through some examples. [less ▲]

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See detailLiving Conditions and Basic Needs: Evidence from African Countries
D'Ambrosio, Conchita UL; Clark, Andrew

in South African Journal of Economics (in press)

We here use five rounds of Afrobarometer data covering more than 100,000 individuals over the 2004-2016 period to explore the link between individual self-reported measures of living conditions and access ... [more ▼]

We here use five rounds of Afrobarometer data covering more than 100,000 individuals over the 2004-2016 period to explore the link between individual self-reported measures of living conditions and access to four basic needs. We not only consider own access to these needs, but also various indices of their deprivation, satisfaction and inequality. We find some evidence of comparisons to those who are better off and to those who are worse off, in terms of access to basic needs, in the evaluation of current living conditions. Overall, however, subjective living conditions are mostly absolute in African countries. There is notable heterogeneity by level of development, with the effect of lack of access to basic needs being more pronounced in poorer countries. Equally, comparisons to the better-off are associated with better living conditions in poorer countries, suggesting the existence of a tunnel effect: this latter disappears with economic development. [less ▲]

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See detailCrime Victimisation Over Time and Sleep Quality
D'Ambrosio, Conchita UL; Clark, Andrew; Zhu, Rong

in Social Science and Medicine - Population Health (in press)

We here consider the relationship between the individual time profile of crime victimisation and sleep quality. Sleep quality worsens with contemporaneous crime victimisation, with physical violence ... [more ▼]

We here consider the relationship between the individual time profile of crime victimisation and sleep quality. Sleep quality worsens with contemporaneous crime victimisation, with physical violence having a larger effect than property crime. But crime history also matters, and past victimisation experience continues to reduce current sleep quality. Last, there is some evidence that the order of victimisation spells plays a role: consecutive years of crime victimisation affect sleep quality more adversely than the same number of years when not contiguous. [less ▲]

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See detailSkewness Risk Premium: Theory and Empirical Evidence
Lin, Yuehao; Lehnert, Thorsten UL; Wolff, Christian UL

in International Review of Financial Analysis (in press)

Using an equilibrium asset and option pricing model in a simple economy under jump diffusion, we show theoretically that the aggregated excess market returns can be predicted by the skewness risk premium ... [more ▼]

Using an equilibrium asset and option pricing model in a simple economy under jump diffusion, we show theoretically that the aggregated excess market returns can be predicted by the skewness risk premium, which is constructed to be the difference between the physical and the risk-neutral skewness. In an empirical application of the model using more than 20 years of data on S&P500 index options, we find that, in line with theory, risk-averse investors demand risk-compensation for holding stocks when the market skewness risk premium is high. However, when we characterize periods of high and low risk aversion, we show that in line with theory, the relationship only holds when risk aversion is high. In periods of low risk aversion, investors demand lower risk compensation, thus substantially weakening the skewness-risk-premium-return trade off. [less ▲]

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See detailPlayers' moral decisions in virtual worlds: Morality in video games
Melzer, André UL; Holl, Elisabeth UL

Book published by Oxford University Press (2020)

Detailed reference viewed: 28 (0 UL)
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See detailIoT Device Fingerprinting: Machine Learning based Encrypted Traffic Analysis
Msadek, Mohamed Nizar UL; Soua, Ridha UL; Engel, Thomas UL

in The IEEE Wireless Communications and Networking Conference (WCNC) (2019, April 19)

Even in the face of strong encryption, the spectacular Internet of Things (IoT) penetration across sectors such as e-health, energy, transportation, and entertainment is expanding the attack surface ... [more ▼]

Even in the face of strong encryption, the spectacular Internet of Things (IoT) penetration across sectors such as e-health, energy, transportation, and entertainment is expanding the attack surface, which can seriously harm users’ privacy. We demonstrate in this paper that an attacker is able to disclose sensitive information about the IoT device, such as its type,by identifying specific patterns in IoT traffic. To perform the fingerprint attack, we train machine-learning algorithms based on selected features extracted from the encrypted IoT traffic.Extensive simulations involving the baseline approach show that we achieve not only a significant mean accuracy improvement of 18.5% and but also a speedup of 18.39 times for finding the best estimators. Obtained results should spur the attention of policymakers and IoT vendors to secure the IoT devices they bring to market. [less ▲]

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See detailSocial Media as an Opportunity for Public Health Interventions: The #Metoo Movement as an Exemplar
Gomez Bravo, Raquel UL; Gomez Bravo, María; Lygidakis, Charilaos UL et al

in Journal of the International Society for Telemedicine and EHealth (2019), 7(e5), 1-7

Background: Social media have been used exponentially and globally, providing a means for billions of users to connect, interact, share opinions and criticise, becoming one of the main channels of ... [more ▼]

Background: Social media have been used exponentially and globally, providing a means for billions of users to connect, interact, share opinions and criticise, becoming one of the main channels of communication for users around the world. One of the most popular free social media networks is Twitter, with more than 100 million active users per day worldwide. Purpose: The aim of this study was to analyse a sample of the public conversations generated, using the hashtag #MeToo, around the topic of sexual abuse on Twitter. Methods: Using social media marketing software, the use of the #MeToo hashtag was analysed over a period of 60 days (14 September 2017 to 13 November of 2017). Results: The #MeToo conversation was mainly in English (79.3%), located in the United States (48.2% of cases), but with global repercussions. The volume of mentions of the #MeToo hashtag was far greater (97.7%), compared with other hashtags related to violence over this period of time, using mostly Twitter (96.2%). Conclusions: These results suggest that it is possible to describe different groups using the social media, and analyse their conversations to identify opportunities for successful public health interventions. If the topic is relevant for the general public, it will generate interest and conversations at the global level, supported by a universal and borderless channel such as Twitter. [less ▲]

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See detailLe Web des années 1990: entre données et reconstructions
Schafer, Valerie UL

Presentation (2019, April 14)

Cette présentation revient sur les travaux menées autour de l'histoire du Web des années 1990 et présente les enjeux de lecture proche et distante des archives du Web au sein de cette recherche.

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See detailTranslanguaging in a Multilingual Classroom in Luxembourg
Degano, Sarah UL

Presentation (2019, April 12)

Research in bilingual and trilingual schools shows that knowledge and understanding can be increased by translanguaging (Baker & Wright 2017, Kirsch 2017), the enactment of a student’s linguistic and non ... [more ▼]

Research in bilingual and trilingual schools shows that knowledge and understanding can be increased by translanguaging (Baker & Wright 2017, Kirsch 2017), the enactment of a student’s linguistic and non-linguistic resources. Yet, research on translanguaging including migrant languages in multilingual schools remains scarce (Duarte 2018). In multilingual Luxembourg, over 60% of the students indicate to have a dominant home language other than Luxembourgish, with Portuguese being the most used language (MENJE 2018). Considering that theteaching of Luxembourgish, French and German accounts for 40.5% of the instruction time, little room is left for the students’ home languages and the school system is particularly challenging for the students whose language repertoires deviate from the official curriculum. The present doctoral project investigates how primary school students with a migration background deploy their language repertoires to learn. In this paper, I examine the extent to which two fourth-graders with a Portuguese background and a different migration experience mobilize their languages while interacting with the teacher and peers. Data stem from eighteen days of observation and video-recordings. The thematic analysis focuses on the students’ participation and their language use in different school subjects. Preliminary findings show that the students participate unequally and use their languages differently in terms of purpose and frequency and depending on their migration experience. The findings are tentative because data collection is on-going. [less ▲]

Detailed reference viewed: 41 (2 UL)
See detailBORDERS IN THE LIVES OF ASYLUM SEEKERS & REFUGEES IN LUXEMBOURG & METZ
Paraschivescu, Claudia UL

E-print/Working paper (2019)

Detailed reference viewed: 38 (1 UL)
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See detailImproved Monitoringand Tracking Hurricanes using GPS Atmospheric WaterVapour
Ejigu, Yohannes Getachew; Teferle, Felix Norman UL; klose, Anna et al

Poster (2019, April 09)

Detailed reference viewed: 39 (2 UL)
See detailMortgages and Life Time Contracts
Ratti, Luca UL

Scientific Conference (2019, April 05)

Detailed reference viewed: 46 (0 UL)
See detailHistorische Karten aus der Maas-Mosel-Region - Analysemethoden zur Komplexität historischer Grenzen in der Praxis
Uhrmacher, Martin UL

Presentation (2019, April 05)

Grenzen auf historischen Karten sind stets Ausdruck eines Machtanspruchs, den sie räumlich darstellen. Sie bringen den Zusammenhang zwischen Kartographischer und realer Macht in Form von Punkten, Strichen ... [more ▼]

Grenzen auf historischen Karten sind stets Ausdruck eines Machtanspruchs, den sie räumlich darstellen. Sie bringen den Zusammenhang zwischen Kartographischer und realer Macht in Form von Punkten, Strichen oder Linien gewissermaßen auf das Blatt. Kartographie und Grenzen gehören deshalb im Kontext der Territorialpolitik auch untrennbar zusammen. Karten dienen einerseits nach innen einer möglichst präzisen Raumerfassung und somit als wichtige Informationsquelle und Orientierungshilfe für den Landesherrn. Gleichzeitig werden sie aber auch nach außen als Mittel politischer Propaganda und zur Durchsetzung von territorialen Ansprüchen gebraucht. Durch die Analyse kartographischer Quellen wird eine tiefergehende Annäherung an die Charakteristik und Ausprägung von Grenzräumen versucht. Dazu werden exemplarisch zwei Grenzregionen in den Blick genommen: Zum einen die luxemburgisch-französische Grenze des 17. und 18. Jahrhunderts sowie die kurtrierisch-luxemburgische Grenze im späten 18. Jahrhundert. Wie lassen sich Grenzen in dieser Zeit definieren und welche Funktion spielten Karten bei ihrer Festlegung, Ausprägung und Durchsetzung? [less ▲]

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See detailKartographische Ressourcen im Internet, ein Überblick
Uhrmacher, Martin UL

Presentation (2019, April 05)

Detailed reference viewed: 35 (1 UL)
See detailGoogle My Maps: Ein Tool für die Erstellung einfacher historischer Karten
Uhrmacher, Martin UL

Presentation (2019, April 05)

Detailed reference viewed: 43 (4 UL)
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See detailDesign and Cryptanalysis of Symmetric-Key Algorithms in Black and White-box Models
Udovenko, Aleksei Nikolaevich UL

Doctoral thesis (2019)

Cryptography studies secure communications. In symmetric-key cryptography, the communicating parties have a shared secret key which allows both to encrypt and decrypt messages. The encryption schemes used ... [more ▼]

Cryptography studies secure communications. In symmetric-key cryptography, the communicating parties have a shared secret key which allows both to encrypt and decrypt messages. The encryption schemes used are very efficient but have no rigorous security proof. In order to design a symmetric-key primitive, one has to ensure that the primitive is secure at least against known attacks. During 4 years of my doctoral studies at the University of Luxembourg under the supervision of Prof. Alex Biryukov, I studied symmetric-key cryptography and contributed to several of its topics. Part I is about the structural and decomposition cryptanalysis. This type of cryptanalysis aims to exploit properties of the algorithmic structure of a cryptographic function. The first goal is to distinguish a function with a particular structure from random, structure-less functions. The second goal is to recover components of the structure in order to obtain a decomposition of the function. Decomposition attacks are also used to uncover secret structures of S-Boxes, cryptographic functions over small domains. In this part, I describe structural and decomposition cryptanalysis of the Feistel Network structure, decompositions of the S-Box used in the recent Russian cryptographic standard, and a decomposition of the only known APN permutation in even dimension. Part II is about the invariant-based cryptanalysis. This method became recently an active research topic. It happened mainly due to recent extreme cryptographic designs, which turned out to be vulnerable to this cryptanalysis method. In this part, I describe an invariant-based analysis of NORX, an authenticated cipher. Further, I show a theoretical study of linear layers that preserve low-degree invariants of a particular form used in the recent attacks on block ciphers. Part III is about the white-box cryptography. In the white-box model, an adversary has full access to the cryptographic implementation, which in particular may contain a secret key. The possibility of creating implementations of symmetric-key primitives secure in this model is a long-standing open question. Such implementations have many applications in industry; in particular, in mobile payment systems. In this part, I study the possibility of applying masking, a side-channel countermeasure, to protect white-box implementations. I describe several attacks on direct application of masking and provide a provably-secure countermeasure against a strong class of the attacks. Part IV is about the design of symmetric-key primitives. I contributed to design of the block cipher family SPARX and to the design of a suite of cryptographic algorithms, which includes the cryptographic permutation family SPARKLE, the cryptographic hash function family ESCH, and the authenticated encryption family SCHWAEMM. In this part, I describe the security analysis that I made for these designs. [less ▲]

Detailed reference viewed: 44 (5 UL)
See detail[Rezension] Lars Nowak (Hg.): Medien - Krieg - Raum
Pause, Johannes UL

in MEDIENwissenschaft: Rezensionen, Reviews (2019), 1(2019), 24-27

Detailed reference viewed: 27 (2 UL)