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See detailLuaxtlas - A digital and interactive historical atlas of the city of Luxembourg - Beta Version
Uhrmacher, Martin UL; Kass, Steve UL; Pauli, Sebastian et al

Cartographic material (2019)

Since 2016, the university research project VILLUX X, in collaboration with the City of Luxembourg, is working on the creation of a digital historical atlas. This atlas shows the urban development of ... [more ▼]

Since 2016, the university research project VILLUX X, in collaboration with the City of Luxembourg, is working on the creation of a digital historical atlas. This atlas shows the urban development of Luxembourg since the beginning of the 19th century in the form of digital and interactive maps. The profound processes of change in Luxembourg and the growth of the city can be traced interactively in several time sections from the 1820s onwards: From the narrow fortified city of the early 19th century to the large-scale international metropolis of the 21st century. [less ▲]

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See detailSearch-based Test and Improvement of Machine-Learning-Based Anomaly Detection Systems
Cordy, Maxime UL; Muller, Steve; Papadakis, Mike UL et al

in ACM SIGSOFT International Symposium on Software Testing and Analysis (2019)

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See detailSearching for materials with high refractive index and wide band gap: A first-principles high-throughput study
Naccarato, Francesco; Ricci, Francesco; Suntivich, Jin et al

in PHYSICAL REVIEW MATERIALS (2019), 3(4), 044602-12

Materials combining both a high refractive index and a wide band gap are of great interest for optoelectronic and sensor applications. However, these two properties are typically described by an inverse ... [more ▼]

Materials combining both a high refractive index and a wide band gap are of great interest for optoelectronic and sensor applications. However, these two properties are typically described by an inverse correlation with high refractive index appearing in small gap materials and vice versa. Here, we conduct a first-principles high-throughput study on more than 4000 semiconductors (with a special focus on oxides). Our data confirm the general inverse trend between refractive index and band gap but interesting outliers are also identified. The data are then analyzed through a simple model involving two main descriptors: the average optical gap and the effective frequency. The former can be determined directly from the electronic structure of the compounds, but the latter cannot. This calls for further analysis in order to obtain a predictive model. Nonetheless, it turns out that the negative effect of a large band gap on the refractive index can be counterbalanced in two ways: (i) by limiting the difference between the direct band gap and the average optical gap which can be realized by a narrow distribution in energy of the optical transitions and (ii) by increasing the effective frequency which can be achieved through either a high number of transitions from the top of the valence band to the bottom of the conduction band or a high average probability for these transitions. Focusing on oxides, we use our data to investigate how the chemistry influences this inverse relationship and rationalize why certain classes of materials would perform better. Our findings can be used to search for new compounds in many optical applications both in the linear and nonlinear regime (waveguides, optical modulators, laser, frequency converter, etc.). [less ▲]

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See detailExciton-Phonon Coupling in the Ultraviolet Absorption and Emission Spectra of Bulk Hexagonal Boron Nitride
Paleari, Fulvio UL; Miranda, Henrique P. C.; Molina-Sanchez, Alejandro et al

in PHYSICAL REVIEW LETTERS (2019), 122(18), 187401-6

We present an ab initio method to calculate phonon-assisted absorption and emission spectra in the presence of strong excitonic effects. We apply the method to bulk hexagonal BN, which has an indirect ... [more ▼]

We present an ab initio method to calculate phonon-assisted absorption and emission spectra in the presence of strong excitonic effects. We apply the method to bulk hexagonal BN, which has an indirect band gap and is known for its strong luminescence in the UV range. We first analyze the excitons at the wave vector (q) over bar of the indirect gap. The coupling of these excitons with the various phonon modes at (q) over bar is expressed in terms of a product of the mean square displacement of the atoms and the second derivative of the optical response function with respect to atomic displacement along the phonon eigenvectors. The derivatives are calculated numerically with a finite difference scheme in a supercell commensurate with (q) over bar. We use detailed balance arguments to obtain the intensity ratio between emission and absorption processes. Our results explain recent luminescence experiments and reveal the exciton-phonon coupling channels responsible for the emission lines. [less ▲]

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See detailUsing Models to Enable Compliance Checking against the GDPR: An Experience Report
Torre, Damiano UL; Soltana, Ghanem UL; Sabetzadeh, Mehrdad UL et al

in To appear in the proceeding of the IEEE / ACM 22nd International Conference on Model Driven Engineering Languages and Systems (MODELS 19) (2019)

The General Data Protection Regulation (GDPR) harmonizes data privacy laws and regulations across Europe. Through the GDPR, individuals are able to better control their personal data in the face of new ... [more ▼]

The General Data Protection Regulation (GDPR) harmonizes data privacy laws and regulations across Europe. Through the GDPR, individuals are able to better control their personal data in the face of new technological developments. While the GDPR is highly advantageous to citizens, complying with it poses major challenges for organizations that control or process personal data. Since no automated solution with broad industrial applicability currently exists for GDPR compliance checking, organizations have no choice but to perform costly manual audits to ensure compliance. In this paper, we share our experience building a UML representation of the GDPR as a first step towards the development of future automated methods for assessing compliance with the GDPR. Given that a concrete implementation of the GDPR is affected by the national laws of the EU member states, GDPR’s expanding body of case laws and other contextual information, we propose a two-tiered representation of the GDPR: a generic tier and a specialized tier. The generic tier captures the concepts and principles of the GDPR that apply to all contexts, whereas the specialized tier describes a specific tailoring of the generic tier to a given context, including the contextual variations that may impact the interpretation and application of the GDPR. We further present the challenges we faced in our modeling endeavor, the lessons we learned from it, and future directions for research. [less ▲]

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See detailImpulsivity and Binge Drinking: A Neurocognitive Perspective (chapter 35)
Maurage, Pierre; Lannoy, Séverine; Naassila, Mickael et al

in Preedy, Victor R. (Ed.) Neuroscience of Alcohol (2019)

Binge drinking (BD), an alcohol-consumption pattern characterized by frequent alternations between intense intakes and withdrawal periods, is a widespread habit in youth. It has been shown that BD is ... [more ▼]

Binge drinking (BD), an alcohol-consumption pattern characterized by frequent alternations between intense intakes and withdrawal periods, is a widespread habit in youth. It has been shown that BD is linked to impairments in psychological, cognitive, and cerebral abilities. Previous studies notably underlined that impulsivity-related mechanisms might play a pivotal role in the emergence and maintenance of BD. This chapter underlines the importance of impulsivity in BD, by proposing a literature review organized around a theoretical framework distinguishing four impulsivity subcomponents (urgency, lack of premeditation, lack of perseverance, and sensation seeking) and by identifying the (neuro-)psychological and cerebral correlates of each subcomponent. Then, the main challenges for future research are discussed, particularly underlining the need for a multidisciplinary approach to explore the links between impulsivity and other cognitive factors, the causal relationships between BD and impulsive subcomponents, and the interindividual variations of impulsive tendencies in BD. [less ▲]

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See detailTheory of resonant Raman scattering: Towards a comprehensive ab initio description
Reichardt, Sven; Wirtz, Ludger UL

in PHYSICAL REVIEW B (2019), 99(17), 174312-15

We develop a general, fully quantum mechanical theory of Raman scattering from first principles in terms of many-body correlation functions. In order to arrive at expressions that are practically useful ... [more ▼]

We develop a general, fully quantum mechanical theory of Raman scattering from first principles in terms of many-body correlation functions. In order to arrive at expressions that are practically useful in the context of condensed matter physics, we adopt the Lehmann-Symanzik-Zimmermann reduction formula from high-energy physics and formulate it in the language of many-body perturbation theory. This enables us to derive a general and practically useful expression for the Raman scattering rate in terms of quantities that can be computed ab initio. Our work paves the way toward a comprehensive computational approach to the calculation of Raman spectra that goes beyond the current state of the art by capturing both excitonic and nonadiabatic effects. [less ▲]

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See detailDetecting misalignments between system security and user perceptions: a preliminary socio-technical analysis of an E2E email encryption system
Stojkovski, Borce UL; Vazquez Sandoval, Itzel UL; Lenzini, Gabriele UL

in 4th European Workshop on Usable Security - 2019 IEEE European Symposium on Security and Privacy Workshops (2019)

The set of impressions that a user has about distinct aspects of a system depends on the experience perceived while interacting with the system. Considering the effects of these interactions in a security ... [more ▼]

The set of impressions that a user has about distinct aspects of a system depends on the experience perceived while interacting with the system. Considering the effects of these interactions in a security analysis allows for a new class of security properties in terms of misalignments between the system’s technical guarantees and the user’s impressions of them. For instance, a property that we call “false sense of insecurity” identifies a situation in which a secure system injects uncertainty in users, thus improperly transmitting the degree of protection that it actually provides; another, which we call “false sense of security”, captures situations in which a system instills a false sense of security beyond what a technical analysis would justify. Both situations leave room for attacks. In this paper we propose a model to define and reason about such socio-technical misalignments. The model refers to and builds on the concept of security ceremonies, but relies on user experience notions and on security analysis techniques to put together the information needed to verify misalignment properties about user’s impressions and system’s security guarantees. We discuss the innovative insight of this pilot model for a holistic understanding of a system’s security. We also propose a formal model that can be used with existing model checkers for an automatic analysis of misalignments. We exemplify the approach by modelling one specific application for end-to-end email encryption within which we analyze a few instances of misalignment properties. [less ▲]

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See detailSemantic Fuzzing with Zest
Padhye, Rohan; Lemieux, Caroline; Sen, Koushik et al

in ACM SIGSOFT International Symposium on Software Testing and Analysis (2019)

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See detailAn Empirical Study on Vulnerability Prediction of Open-Source Software Releases
Jimenez, Matthieu; Rwemalika, Renaud UL; Papadakis, Mike UL et al

in Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering (ESEC/FSE) (2019)

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See detailMart: A Mutant Generation Tool for LLVM
Titcheu Chekam, Thierry UL; Papadakis, Mike UL; Le Traon, Yves UL

in Titcheu Chekam, Thierry; Papadakis, Mike; Le Traon, Yves (Eds.) Mart: A Mutant Generation Tool for LLVM (2019)

Program mutation makes small syntactic alterations to programs' code in order to artificially create faulty programs (mutants). Mutants are used, in software analysis, to evaluate and improve test suites ... [more ▼]

Program mutation makes small syntactic alterations to programs' code in order to artificially create faulty programs (mutants). Mutants are used, in software analysis, to evaluate and improve test suites. Mutants creation (generation) tools are often characterized by their mutation operators and the way they create and represent the mutants. This paper presents Mart, a mutants generation tool, for LLVM bitcode, that supports the fine-grained definition of mutation operators (as matching rule - replacing pattern pair; uses 816 defined pairs by default) and the restriction of the code parts to mutate. New operators are implemented in Mart by implementing their matching rules and replacing patterns. Mart also implements in-memory Trivial Compiler Equivalence to eliminate equivalent and duplicate mutants during mutants generation. Mart generates mutant code as separated mutant files, meta-mutants file, weak mutation, and mutant coverage instrumented files. The generated LLVM bitcode files can be interpreted using an LLVM interpreter or compiled into native code. Mart is publicly available (https://github.com/thierry-tct/mart) for use by researchers and practitioners. Mart has been applied to generate mutants for several research experiments and generated more than 4,000,000 mutants. [less ▲]

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See detailConcise UC Zero-Knowledge Proofs for Oblivious Updatable Databases
Camenisch, Jan; Dubovitskaya, Maria; Rial Duran, Alfredo UL

E-print/Working paper (2019)

We propose an ideal functionality $\Functionality_{\COMD}$ and a construction for oblivious and updatable committed databases. $\Functionality_{\COMD}$ allows a prover to read, write, and update values in ... [more ▼]

We propose an ideal functionality $\Functionality_{\COMD}$ and a construction for oblivious and updatable committed databases. $\Functionality_{\COMD}$ allows a prover to read, write, and update values in a database and to prove to a verifier in zero-knowledge that a value is read from or written into a certain position. The following properties must hold: (1) values stored in the database remain hidden from the verifier; (2) a value read from a certain position is equal to the value previously written into that position; (3) (obliviousness) both the value read or written and its position remain hidden from the verifier. We describe a construction for $\Functionality_{\COMD}$ based on vector commitments. After the initialization phase, the cost of zero-knowedge proofs for reading and writing is independent of the database size, outperforming other techniques that achieve cost sublinear in the dataset size for prover and/or verifier. Therefore, our construction is especially appealing for cases with large datasets. Finally, we show how to use $\Functionality_{\COMD}$ as a building block in ``commit-and-prove'' two-party protocols, i.e.\ protocols where the prover commits to her inputs and subsequently proves in zero-knowledge statements about the committed values. In comparison to simply using commitment schemes, our construction allows the prover to hide positions read or written efficiently, which is useful to design protocols for e.g.\ cloud-based services, blockchain, privacy-preserving location sharing services and e-commerce, and efficient OR proofs. [less ▲]

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See detailLe fondement de l'effet des jugements étrangers
Cuniberti, Gilles UL

Book published by Brill (2019)

Comment justifier de faire produire effet aux jugements rendus par des tribunaux étrangers? La question est ancienne dans le monde de common law. Tant l’Angleterre que les Etats-Unis ont développé des ... [more ▼]

Comment justifier de faire produire effet aux jugements rendus par des tribunaux étrangers? La question est ancienne dans le monde de common law. Tant l’Angleterre que les Etats-Unis ont développé des théories originales fondant l’accueil des jugements étrangers et dessinant une partie du régime de cet accueil. Dans la tradition juridique continentale, la question du fondement de l’effet des jugements étrangers n’a en revanche guère été approfondie. Elle devrait pourtant être essentielle, en permettant soit d’expliquer les solutions retenues par le droit positif, soit de les rationaliser. Ce cours présente et critique les différentes théories et fondements existant en droit comparé. Certaines mettent en avant les intérêts privés des justiciables, à l’instar du droit à l’exécution des jugements promu par la Cour européenne des droits de l’homme. D’autres privilégient les intérêts des Etats, qu’ils soient purement économiques ou plus politiques. Enfin, le cours s’interroge sur le fondement de la circulation des jugements dans les systèmes fédéraux, en insistant plus particulièrement sur le principe de confiance mutuelle prévalant dans l’Union européenne. [less ▲]

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See detailThe OECD and Higher Education Policy: Agenda-Setting, Organizational Dynamics and the Construction of Convening Authority
Harmsen, Robert UL; Braband, Gangolf

in Higher Education Policy (2019)

The article examines the engagement of the Organization for Economic Cooperation and Development (OECD) with the higher education sector. Detailed empirical case studies probe the ultimate failure to ... [more ▼]

The article examines the engagement of the Organization for Economic Cooperation and Development (OECD) with the higher education sector. Detailed empirical case studies probe the ultimate failure to launch of the OECD’s Assessment of Higher Education Learning Outcomes (AHELO) initiative, as well as the recent demise of the long-established Institutional Management in Higher Education (IMHE) programme and the development of a new initiative on the evaluation of higher education system performance. The analysis is informed by a theoretical framework drawn from the wider international organization literature, focusing on internal organizational dynamics and the manner in which international organizations seek to construct their external authority. A complex portrait of the OECD as a policy actor correspondingly emerges, focused on agenda-setting within the organization in terms which highlight the interplay of organizational, governmental and stakeholder interests. This is further suggestive of a broader research agenda exploring emerging international-level policy processes in higher education. [less ▲]

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See detailCross-Border Cooperation in Europe: A relational perspective
Nienaber, Birte UL; Wille, Christian UL

in European Planning Studies (2019)

Cross-border cooperation, border regions, soft spaces? This special issue approaches cross-border informal planning processes in cross-border regions by analysing them from a perspective that combines ... [more ▼]

Cross-border cooperation, border regions, soft spaces? This special issue approaches cross-border informal planning processes in cross-border regions by analysing them from a perspective that combines networks, governance and territorialization. Such a relational perspective will be developed by papers which deal with a variety of European cross-border regions and empirical evidence related to the nexus of networks, governance and territorialization. [less ▲]

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See detailNAI: The Normative Reasoner
Libal, Tomer UL; Steen, Alexander UL

in Bex, Floris (Ed.) Proceedings of the Seventeenth International Conference on Artificial Intelligence and Law (2019)

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See detailThe Higher-Order Prover Leo-III (Extended Abstract)
Steen, Alexander UL; Benzmüller, Christoph UL

in Benzmüller, Christoph; Stuckenschmidt, Heiner (Eds.) {KI} 2019: Advances in Artificial Intelligence - 42nd German Conference on AI, Kassel, Germany, September 23-26, 2019, Proceedings (2019)

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See detailPerzeptionslinguistik arealer Sprachvariation im Deutschen
Purschke, Christoph UL; Stoeckle, Philipp

in Herrgen, Joachim; Schmidt, Jürgen Erich (Eds.) Sprache und Raum – Deutsch. Ein internationales Handbuch der Sprachvariation (2019)

Detailed reference viewed: 35 (0 UL)