References of "Scientific congresses, symposiums and conference proceedings"
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See detailProceedings of the 6th Global Conference on Artificial Intelligence (GCAI 2020)
Danoy, Grégoire UL; Pang, Jun UL; Sutcliffe

in 6th Global Conference on Artificial Intelligence (2020, May)

Detailed reference viewed: 88 (5 UL)
See detailConstcamer Paintings as Epistemic Images: Early Modern Theaters of Wisdom
Koeleman, Floor UL

Scientific Conference (2020, April 04)

This paper argues, against existing literature, that 17th-cent. constcamer paintings were objects to think with, functioning as the two-dimensional space of artificial memory. In turn, these artworks ... [more ▼]

This paper argues, against existing literature, that 17th-cent. constcamer paintings were objects to think with, functioning as the two-dimensional space of artificial memory. In turn, these artworks complicate conventional definitions of epistemic images more broadly. I focus on an analysis of constcamer paintings accounting for the reception of the ancients and the mnemonic and propaedeutic role of images, entailing concepts such as wonder or thauma (from Greek θεάομαι), the drive to gather knowledge, memory as the locus of this ‘collection’, and recollecting as the intellectual process of interaction with memorized knowledge. The term inventor, referring to the creator of a given collection, is derived from the rhetorical technique for the retrieval of information. The theatre or ‘place for viewing’ provided the physical context for the collected wisdom. Inventors of constcamer paintings – often artists themselves – vitally participated in knowledge formation contributing to contemporary intellectual debates. [less ▲]

Detailed reference viewed: 115 (4 UL)
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See detailDoes Conscientiousness Matter for Academic Success? Considering Different Facets of Conscientiousness and Different Educational Outcomes
Franzen, Patrick UL; van der Westhuizen, Lindie UL; Arens, A. Katrin et al

Poster (2020, April)

Conscientiousness is the strongest BIG-5 predictor of academic success. Both conscientiousness and academic success are broad concepts, consisting of multiple lower level facets. Conscientiousness facets ... [more ▼]

Conscientiousness is the strongest BIG-5 predictor of academic success. Both conscientiousness and academic success are broad concepts, consisting of multiple lower level facets. Conscientiousness facets might display differential relations to different indicators of academic success. To investigate these relations, conscientiousness facets need to be measured in an economic and valid way. We conducted two studies, validating a short conscientiousness scale measuring seven facets of conscientiousness (Industriousness, Task Planning, Perfectionism, Procrastination Refrainment, Tidiness, Control, Cautiousness), and testing the relations of these facets with GPA, test scores, school satisfaction, and engagement. The results supported the validity of the scale. Industriousness, Perfectionism, and Cautiousness revealed the highest relations to academic outcomes. GPA and test scores showed differential associations with the different conscientiousness facets. [less ▲]

Detailed reference viewed: 57 (1 UL)
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See detailLOVBench: Ontology Ranking Benchmark
Kolbe, Niklas UL; Vandenbussche, Pierre-Yves; Kubler, Sylvain UL et al

in Proceedings of The Web Conference 2020 (WWW '20) (2020, April)

Detailed reference viewed: 37 (9 UL)
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See detailNeuere Methoden zur Identifikation und Lokalisierung von Schäden an vorgespannten Betonbrücken
Maas, Stefan UL; Nguyen, Viet Ha UL; Kebig, Tanja UL

in Bischoff, Manfred; von Scheven, Malte; Oesterle, Bernd (Eds.) Baustatik-Baupraxis 14 (2020, March 23)

Zuerst wird ein rein statistischer Schadensindikator basierend auf der Hauptkomponentenanalyse vorgestellt. Wichtig sind Referenzmessungen im ungeschädigten Zustand, um Veränderungen zu identifizieren ... [more ▼]

Zuerst wird ein rein statistischer Schadensindikator basierend auf der Hauptkomponentenanalyse vorgestellt. Wichtig sind Referenzmessungen im ungeschädigten Zustand, um Veränderungen zu identifizieren. Bevor die Messdaten mit den Rechenmodellen kombiniert werden, müssen Temperatureffekte kompensiert werden, um dann die Schäden zu erkennen und zu lokalisieren. Ein „Model-Updating“ Prozess eines speziellen Finite-Elemente- Modells passt die Steifigkeitsmatrix an die gemessenen Eigenfrequenzen oder an die progressive Absenkung unter Eigengewicht an. [less ▲]

Detailed reference viewed: 42 (6 UL)
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See detailAgentenbasierte, hybride Steuerungsarchitektur für cyberphysische Refabrikationssysteme
Groß, Sebastian UL; Gerke, Wolfgang; Plapper, Peter UL

in Jäkel, Jens; Thiel, Robert (Eds.) Tagungsband AALE 2020 Automatisierung und Mensch-Technik-Interaktion (2020, March 05)

Detailed reference viewed: 65 (1 UL)
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See detailMensch-Roboter-Kollaboration in der Domäne Refabrikation – State-of-the-Art und Ausblick
Groß, Sebastian UL; Gerke, Wolfgang; Plapper, Peter UL

in Jäkel, Jens; Thiel, Robert (Eds.) Tagungsband AALE 2020 Automatisierung und Mensch-Technik-Interaktion (2020, March 05)

Detailed reference viewed: 62 (0 UL)
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See detailStructured Compression of Deep Neural Networks with Debiased Elastic Group LASSO
Oyedotun, Oyebade UL; Aouada, Djamila UL; Ottersten, Björn UL

in IEEE 2020 Winter Conference on Applications of Computer Vision (WACV 20), Aspen, Colorado, US, March 2–5, 2020 (2020, March 01)

Detailed reference viewed: 69 (7 UL)
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See detailTowards an Executable Methodology for the Formalization of Legal Texts
Libal, Tomer UL; Steen, Alexander UL

in Dastani, Mehdi; Dong, Huimin; van der Torre, Leon (Eds.) Logic and Argumentation. CLAR 2020 (2020, March)

A methodology for the formalization of legal texts is presented. This methodology is based on features of the NAI Suite, a recently developed formalization environment for legal texts. The ability of the ... [more ▼]

A methodology for the formalization of legal texts is presented. This methodology is based on features of the NAI Suite, a recently developed formalization environment for legal texts. The ability of the tool to execute queries is used in order to drive a correct formalization until all queries are validated. The approach is studied on a fragment of the Smoking Prohibition (Children in Motor Vehicles) (Scotland) Act 2016 of the Scottish Parliament. [less ▲]

Detailed reference viewed: 35 (1 UL)
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See detailAnalyzing PeerFlow -- A Bandwidth Estimation System for Untrustworthy Environments
Mitseva, Asya UL; Engel, Thomas UL; Panchenko, Andriy

in Analyzing PeerFlow -- A Bandwidth Estimation System for Untrustworthy Environments (2020, March)

Detailed reference viewed: 16 (1 UL)
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See detailInvestigating the role of individual differences in the analgesic response to a virtual reality game: An exploratory analysis (accepted submission, but symposium was cancelled due to COVID-19)
Rischer, Katharina Miriam UL; Barcatta, Katharina UL; Battistutta, Layla UL et al

Scientific Conference (2020, March)

Virtual reality (VR) has been shown to be a powerful method of redirecting attention away from pain and is increasingly used in clinical settings as a therapeutic tool for pain treatment. Yet, little is ... [more ▼]

Virtual reality (VR) has been shown to be a powerful method of redirecting attention away from pain and is increasingly used in clinical settings as a therapeutic tool for pain treatment. Yet, little is known about the underlying factors that modulate the size of the analgesic response to a VR game, such as task difficulty and inter-individual differences in pain attitude, emotion regulation habits, executive functions and virtual reality experience. Methods: 101 healthy participants played two versions of the VR game Subnautica, differing in cognitive load (low load vs. high load). In the low load condition, participants navigated along a predefined route. In the high load condition, participants additionally memorized a series of single digits presented along the route. Pain heat thresholds as well as psychophysiological measures (ECG, EDA) were recorded during a resting state period prior to, as well as during, the two VR playing sessions. In addition, participants completed several psychological questionnaires and different executive functioning tasks (Corsi block tapping task, flanker task, go/nogo task) prior to the VR sessions. Results: Preliminary results of a subgroup (N = 66) of the total sample revealed that pain thresholds were significantly higher for the VR playing sessions when compared to the resting state period, with a trend of a higher threshold for the high load condition. Moreover, pain catastrophizing and fear of pain were significant predictors of pain threshold measurements. The complete results will be presented at the symposium. Discussion: Results could shed light on the role of inter-individual differences on the efficacy of VR-based distraction from pain, and potentially elucidate factors that render an individual more likely to benefit from VR as a pain-relieving tool. This may have important consequences for the use of VR as a therapeutic treatment for pain patients. [less ▲]

Detailed reference viewed: 41 (3 UL)
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See detailMetamorphic Security Testing for Web Systems
Mai, Xuan Phu UL; Pastore, Fabrizio UL; Goknil, Arda et al

in IEEE International Conference on Software Testing, Verification and Validation (ICST) 2020 (2020, March)

Security testing verifies that the data and the resources of software systems are protected from attackers. Unfortunately, it suffers from the oracle problem, which refers to the challenge, given an input ... [more ▼]

Security testing verifies that the data and the resources of software systems are protected from attackers. Unfortunately, it suffers from the oracle problem, which refers to the challenge, given an input for a system, of distinguishing correct from incorrect behavior. In many situations where potential vulnerabilities are tested, a test oracle may not exist, or it might be impractical due to the many inputs for which specific oracles have to be defined. In this paper, we propose a metamorphic testing approach that alleviates the oracle problem in security testing. It enables engineers to specify metamorphic relations (MRs) that capture security properties of the system. Such MRs are then used to automate testing and detect vulnerabilities. We provide a catalog of 22 system-agnostic MRs to automate security testing in Web systems. Our approach targets 39% of the OWASP security testing activities not automated by state-of-the-art techniques. It automatically detected 10 out of 12 vulnerabilities affecting two widely used systems, one commercial and the other open source (Jenkins). [less ▲]

Detailed reference viewed: 124 (19 UL)
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See detailLangzeiteffekte von Klassenwiederholungen in der Sekundarstufe
Klapproth, Florian; Keller, Ulrich UL; Fischbach, Antoine UL

Scientific Conference (2020, March)

Detailed reference viewed: 19 (1 UL)
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See detailNAI: Towards Transparent and Usable Semi-Automated Legal Analysis
Libal, Tomer UL; Steen, Alexander UL

in Schweighöfer, Erich; Hötzendorfer, Walter; Kummer, Franz (Eds.) et al Verantwortungsbewusste Digitalisierung, Tagungsband des 23. Internationalen Rechtsinformatik Symposions IRIS 2020 (2020, February 27)

A prototype for automated reasoning over legal documents, called NAI, is presented. It uses formalized representations of legal documents that are created using a graphical editor that is also provided as ... [more ▼]

A prototype for automated reasoning over legal documents, called NAI, is presented. It uses formalized representations of legal documents that are created using a graphical editor that is also provided as part of NAI. The prototype supports several automated reasoning procedures over the given formalizations, including the execution of user queries. The application of NAI is studied using a fragment of the Scottish Smoking Prohibition (Children in Motor Vehicles) Act 2016. [less ▲]

Detailed reference viewed: 62 (6 UL)
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See detailPrivacy and Security of Big Data in AI Systems:A Research and Standards Perspective
Esmaeilzadeh Dilmaghani, Saharnaz UL; Brust, Matthias R. UL; Danoy, Grégoire UL et al

in 2019 IEEE International Conference on Big Data (Big Data), 9-12 December 2019 (2020, February 24)

Detailed reference viewed: 105 (16 UL)
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See detailPreventing Overloading Incidents on Smart Grids: A Multiobjective Combinatorial Optimization Approach
Antoniadis, Nikolaos UL; Cordy, Maxime UL; Sifaleras, Angelo et al

in Communications in Computer and Information Science (2020, February 15)

Cable overloading is one of the most critical disturbances that may occur in smart grids, as it can cause damage to the distribution power lines. Therefore, the circuits are protected by fuses so that ... [more ▼]

Cable overloading is one of the most critical disturbances that may occur in smart grids, as it can cause damage to the distribution power lines. Therefore, the circuits are protected by fuses so that, the overload could trip the fuse, opening the circuit, and stopping the flow and heating. However, sustained overloads, even if they are below the safety limits, could also damage the wires. To prevent overload, smart grid operators can switch the fuses on or off to protect the circuits, or remotely curtail the over-producing/over-consuming users. Nevertheless, making the most appropriate decision is a daunting decision-making task, notably due to contractual and technical obligations. In this paper, we define and formulate the overloading prevention problem as a Multiobjective Mixed Integer Quadratically Constrained Program. We also suggest a solution method using a combinatorial optimization approach with a state-of-the-art exact solver. We evaluate this approach for this real-world problem together with Creos Luxembourg S.A., the leading grid operator in Luxembourg, and show that our method can suggest optimal countermeasures to operators facing potential overloading incidents. [less ▲]

Detailed reference viewed: 224 (25 UL)
See detailVon Imaginationen himmlischer Erlösung bis zum Pogrom – Der Umgang mit Leprakranken im historischen Überblick.
Uhrmacher, Martin UL

Scientific Conference (2020, February 13)

Die Geschichte der Lepra ist geprägt von Elend, Siechtum und Ausgrenzung bis hin zum Pogrom, aber andererseits auch von religiöser Überhöhung, Privilegierung und beispielhafter Fürsorge. Diese Ambivalenz ... [more ▼]

Die Geschichte der Lepra ist geprägt von Elend, Siechtum und Ausgrenzung bis hin zum Pogrom, aber andererseits auch von religiöser Überhöhung, Privilegierung und beispielhafter Fürsorge. Diese Ambivalenz ist sehr typisch für den Umgang mit Leprakranken, auch Leprose genannt, im Mittelalter und in der frühen Neuzeit. Und sie spiegelt sich auch in Vorurteilen wider, mit denen die an Lepra Erkrankten konfrontiert waren. Das Spektrum reicht hier von Imaginationen himmlischer Erlösung bis hin zur Unterstellung von Sünden und Verbrechen. Der Vortrag beschreibt zunächst Ursprünge und Ausprägungen von Vorurteilen gegenüber Leprakranken beschreiben. Kann man überhaupt von „den Leprosen“ sprechen, die stets als typische Randgruppe der mittelalterlichen Gesellschaft bezeichnet werden? Oder führten Vorurteile in unterschiedlichen zeitlichen und sozialen Kontexten womöglich zur Bildung verschiedener Gruppen? Hierzu werden im zweiten Teil ausgewählte Quellenbeispiele in den Blick genommen. Sie zeigen auf, welche konkreten Auswirkungen bestehende Vorurteile in der Praxis auf die Lebenswelt von Leprakranken hatten. Und sie ermöglichen, der Wandlung von Vorurteilsstrukturen in der long durée nachzugehen. [less ▲]

Detailed reference viewed: 79 (3 UL)
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See detailNew opportunities by laser joining of dissimilar materials
Plapper, Peter UL

Scientific Conference (2020, February 13)

The presentation gives an overview about research projects at UL related to laser welding of dissimilar materials. Literature reference at the end enables the reader to dig deeper in case some specific ... [more ▼]

The presentation gives an overview about research projects at UL related to laser welding of dissimilar materials. Literature reference at the end enables the reader to dig deeper in case some specific projects are of interest. [less ▲]

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See detailPIAF : développer la Pensée Informatique et Algorithmique dans l'enseignement Fondamental
Busana, Gilbert UL; Denis, Brigitte; Duflot-Kremer, Marie et al

Poster (2020, February 06)

Dans cet article, nous présentons les objectifs et premières réalisations du projet PIAF soutenu par l’Union Européenne et visant à développer l’apprentissage de la pensée informatique et algorithmique ... [more ▼]

Dans cet article, nous présentons les objectifs et premières réalisations du projet PIAF soutenu par l’Union Européenne et visant à développer l’apprentissage de la pensée informatique et algorithmique dans l’enseignement fondamental. Ce projet rassemble des chercheur·e·s en sciences de l’éducation et en informatique, provenant de quatre pays (Allemagne, Belgique, France et Luxembourg), autour du thème de la formation des enseignant·e·s. Plus concrètement, il s’agit de définir un cadre (référentiel de compétences, scénarios pédagogiques) permettant aux enseignant·e·s de (i) s’approprier le concept de pensée informatique et algorithmique et de (ii) mettre en œuvre des activités d’apprentissage favorisant le développement de cette pensée chez l’enfant. [less ▲]

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See detailEffects of Annealing and Light on Co-evaporated Methylammonium Lead Iodide Perovskites using Kelvin Probe Force Microscopy in Ultra-High Vacuum
Gallet, Thibaut UL; Martin Lanzoni, Evandro UL; Redinger, Alex UL

in 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) (2020, February 06)

Careful surface analysis is essential to understand the electronic and ionic behaviors in perovskite absorbers. In this contribution we discuss Kelvin probe force microscopy performed in ultra-high vacuum ... [more ▼]

Careful surface analysis is essential to understand the electronic and ionic behaviors in perovskite absorbers. In this contribution we discuss Kelvin probe force microscopy performed in ultra-high vacuum on as-grown and annealed co-evaporated methylammonium lead iodide perovskite thin films. By comparing the contact potential difference upon annealing and illumination, we find that annealing increases the average workfunction, indicating a change either in doping or in surface composition. Illumination also increases the average workfunction, indicating a p-type absorber, by reducing band bending as the photo-generated carriers screen the surface states. The effect of light shows a two-step process, with a first fast trend, linked to the surface photovoltage and a second slower trend indicating a possible redistribution of mobile charges. [less ▲]

Detailed reference viewed: 17 (3 UL)
See detailLe relations belgo-luxembourgeoises: une mise en perspective historique
Brüll, Christoph UL

Scientific Conference (2020, February 05)

Detailed reference viewed: 25 (0 UL)
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See detailN point Virasoro algebras considered as Krichever - Novikov type algebras
Schlichenmaier, Martin UL

Scientific Conference (2020, February 04)

Detailed reference viewed: 53 (0 UL)
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See detailOpening the black box of the social learning process: The case of community of practices
Boughattas, Yosra; Geraudel, Mickaël UL; Claeye, Frederic

Scientific Conference (2020, February 04)

Detailed reference viewed: 34 (1 UL)
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See detailIdentifying Unintended Harms of Cybersecurity Measures
Chua, Yi Ting; Parkin, Simon; Edwards, Matthew et al

in Proceedings of ECRIME 2019 (2020, February 01)

Detailed reference viewed: 36 (0 UL)
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See detailEvolving a Deep Neural Network Training Time Estimator
Pinel, Frédéric UL; Yin, Jian-xiong; Hundt, Christian UL et al

in Communications in Computer and Information Science (2020, February)

We present a procedure for the design of a Deep Neural Net- work (DNN) that estimates the execution time for training a deep neural network per batch on GPU accelerators. The estimator is destined to be ... [more ▼]

We present a procedure for the design of a Deep Neural Net- work (DNN) that estimates the execution time for training a deep neural network per batch on GPU accelerators. The estimator is destined to be embedded in the scheduler of a shared GPU infrastructure, capable of providing estimated training times for a wide range of network architectures, when the user submits a training job. To this end, a very short and simple representation for a given DNN is chosen. In order to compensate for the limited degree of description of the basic network representation, a novel co-evolutionary approach is taken to fit the estimator. The training set for the estimator, i.e. DNNs, is evolved by an evolutionary algorithm that optimizes the accuracy of the estimator. In the process, the genetic algorithm evolves DNNs, generates Python-Keras programs and projects them onto the simple representation. The genetic operators are dynamic, they change with the estimator’s accuracy in order to balance accuracy with generalization. Results show that despite the low degree of information in the representation and the simple initial design for the predictor, co-evolving the training set performs better than near random generated population of DNNs. [less ▲]

Detailed reference viewed: 39 (2 UL)
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See detailSystematization of threats and requirements for private messaging with untrusted servers. The case of E-mailing and instant messaging
Symeonidis, Iraklis UL; Lenzini, Gabriele UL

in International Conference on Information Systems Security and Privacy, Malta 25-27 February 2020 (2020, February)

Modern email and instant messaging applications often offer private communications. In doing so, they share common concerns about how security and privacy can be compromised, how they should face similar ... [more ▼]

Modern email and instant messaging applications often offer private communications. In doing so, they share common concerns about how security and privacy can be compromised, how they should face similar threats, and how to comply with comparable system requirements. Assuming a scenario where servers may not be trusted, we review and analyze a list of threats specifically against message delivering, archiving, and contact synchronization. We also describe a list of requirements intended for whom undertakes the task of implementing secure and private messaging. The cryptographic solutions available to mitigate the threats and to comply with the requirements may differ, as the two applications are built on different assumptions and technologies. [less ▲]

Detailed reference viewed: 85 (12 UL)
See detailThe Loneliness of the Vilain : Shakespeare and Schiller
Kohns, Oliver UL

Scientific Conference (2020, February)

Detailed reference viewed: 20 (1 UL)
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See detailTowards Automatic CAD Modeling from 3D Scan Sketch based Representation
Shabayek, Abd El Rahman UL; Aouada, Djamila UL; Cherenkova, Kseniya UL et al

in Proceedings of the 15th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications (VISIGRAPP 2020), GRAPP (2020, February)

Detailed reference viewed: 51 (9 UL)
See detailLocal Organiser, European Shadow Financial Regulatory Committee Meeting
Wolff, Christian UL

Scientific Conference (2020, February)

Detailed reference viewed: 18 (2 UL)
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See detailExploring the Monero Peer-to-Peer Network
Cao, Tong UL; Yu, Jiangshan; Decouchant, Jérémie UL et al

in Cao, Tong; Yu, Jiangshan; Decouchant, Jérémie (Eds.) et al Financial Cryptography and Data Security 2020, Sabah, 10-14 February 2020 (2020, February)

Detailed reference viewed: 57 (4 UL)
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See detailShort paper: Mechanized Proofs of Verifiability and Privacy in a paper-based e-voting Scheme
Zollinger, Marie-Laure UL; Roenne, Peter UL; Ryan, Peter UL

in International Conference on Financial Crypto Workshop on Advances in Secure Electronic Voting (2020, February)

Detailed reference viewed: 53 (1 UL)
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See detailWhen a Master Dies: Speculation and Asset Float”
Penasse, Julien UL; Renneboog,, Luc; Scheinkman, José A.

Scientific Conference (2020, January 30)

Detailed reference viewed: 26 (0 UL)
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See detailEtudes universitaires sur le Luxembourg: Mots d'accueil
Bisdorff, Raymond UL

Scientific Conference (2020, January 28)

Concise historical review of 20 years of interdisciplinary Luxembourg studies before the foundation of the University of Luxembourg

Detailed reference viewed: 23 (0 UL)
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See detailLa pluralité des marchés du travail au Luxembourg
Pigeron-Piroth, Isabelle UL

Scientific Conference (2020, January 28)

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See detailWhy is the Market Skewness-Return Relationship Negative?
Lehnert, Thorsten UL

Scientific Conference (2020, January 23)

The observed negative relationship between market skewness and excess return or the negative price of market skewness risk in the cross-section of stock returns is somewhat counterintuitive when we ... [more ▼]

The observed negative relationship between market skewness and excess return or the negative price of market skewness risk in the cross-section of stock returns is somewhat counterintuitive when we consider the usual interpretation of e.g. option-implied skewness as an indicator of jump risk or downside risk. One possible explanation for this inconsistency is that there are factors affecting option-implied market skewness other than jump risk in the stock market. In this paper, I find that price pressure associated with “crowded trades” of mutual funds is an important endogenous factor. Given that retail investors are prone to herding, the directional trading of mutual funds is correlated, and their collective actions can generate short-term price pressure on aggregate stock prices. Short sellers systematically exploit these patterns not only in the equity lending market, but also in the options market. In line with this economic channel, I find that firstly, the significant negative relationship between market skewness and returns becomes insignificant, once I control for price pressure. Secondly, the negative relationship is only present for the “bad” downside component of risk-neutral skewness, associated with out-of-the-money put options. For the “good” upside component of risk-neutral skewness, associated with out-of-the-money call options, the relationship is always positive. Thirdly, price pressure affects the skewness-return relationship, which can be clearly distinguished from the impact of flows on the volatility-return relationship in terms of the leverage effect. [less ▲]

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See detailTeaching DevOps in Academia and Industry: Reflections and Vision
Bobrov, Evgeny; Bucchiarone, Antonio; Capozucca, Alfredo UL et al

in Bruel, Jean-Michel; Mazzara, Manuel; Meyer, Bertrand (Eds.) Software Engineering Aspects of Continuous Development and New Paradigms of Software Production and Deployment (2020, January 19)

The new century brought us a kind of renaissance in software development methods. The advent of the Agile manifesto has led to greater appreciation of methodologies aimed at producing valuable software ... [more ▼]

The new century brought us a kind of renaissance in software development methods. The advent of the Agile manifesto has led to greater appreciation of methodologies aimed at producing valuable software through continuous incremental cycles. More recently, a new set of practices enclosed under the term DevOps has appeared to attain manifesto's objectives in more efficient manner. The software development community has already noticed the benefits brought by DevOps. Thus, the necessity of education in the field becomes more and more important, both from the technical and organisational point of view. This paper describes parallel experiences of teaching both undergraduate and graduate students at the university, and junior professional developers in industry, compares the two approaches and sums up the lessons learnt. A vision driven by the DevOps practices aimed at implementing a shift in the Software Engineering Higher Education curricula to takeover its current limitations is also reported at the end of the paper. [less ▲]

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See detailFostering process related skills in mathematics though educational technology in elementary schools
Haas, Ben; Kreis, Yves UL

Scientific Conference (2020, January 17)

The Teaching in elementary school is mostly based on paper-pencil approaches and does not yet rely primary on educational technologies. But educational technology has found its way into the elementary ... [more ▼]

The Teaching in elementary school is mostly based on paper-pencil approaches and does not yet rely primary on educational technologies. But educational technology has found its way into the elementary schools, this based on various numbers of governmental initiatives launched during the last years in Luxemburg. The aims of these initiatives were to support students in mathematics and foremost render improvements on both skill settings, content and process. However using educational technology in mathematics does not jointly mean teaching and learning process skills. There are many different types of educational technology in mathematics, from tutoring systems to dynamic mathematical software and drill and practice software, only to name those as examples. We want to identify educational technologies and methodologies which are most likely to foster process skills (problem solving, modeling, argumenting, representing and communicating) in mathematics. Therefore we would work on a set of educational technologies offered to the students in elementary school in Luxemburg and evaluate their impacts on the fostering of process skills in mathematics. [less ▲]

Detailed reference viewed: 47 (5 UL)
See detailStudents’ perceptions of instructional quality: Validating 3 dimensions on a lesson-to-lesson basis
Talic, Irma UL; Möller, Jens; Niepel, Christoph UL

Scientific Conference (2020, January 17)

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See detail„Entweder man kann’s oder man lässt es bleiben.“ Kritische Gedanken zur Ausbildung von Blasmusikdirigenten
Sagrillo, Damien UL

Scientific Conference (2020, January 17)

Diesen Karl Böhm in den Mund gelegten Satz passt zu seinem Naturell. Sein Sarkasmus und Zynismus waren bekannt. Karl Böhm hat nie ein Dirigierstudium absolviert. Dennoch gehörte er zu den Großen seines ... [more ▼]

Diesen Karl Böhm in den Mund gelegten Satz passt zu seinem Naturell. Sein Sarkasmus und Zynismus waren bekannt. Karl Böhm hat nie ein Dirigierstudium absolviert. Dennoch gehörte er zu den Großen seines Fachs. In der Fachzeitschrift „das Orchester“ ist im Zusammenhang mit dem berufsausbildenden Angebot für Blasorchesterdirigenten folgendes zu lesen: „Marschmusik oder leichtere Muse haben keinen Platz im Curriculum, die Konzentration liegt auf der Literatur für Sinfonisches Blasorchester“ Diese Aussage gehört kritisch hinterfragt. In meinem Vortrag steht infolgedessen zweierlei im Vordergrund. Zum einen: Was ist ein sinfonisches Blasorchester bzw. eine Bläserphilharmonie – wo kommen die Begriffe her, worauf zielen sie ab? Zum anderen: Marchmusik und sog. „leichte Muse“ gehören zum Wesen lokaler Musikvereine. Wieso finden diese als Tradition zu bezeichnenden Genres der Blasmusik in der Ausbildung keinen Platz? In der Zusammenfassung der beiden voraus gestellten Fragen lassen sich Schlussfolgerungen für die Ausbildung von Blasmusikdirigenten ziehen. [less ▲]

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See detailReal Time Holding Control for Multiline Networks
Laskaris, Georgios UL; Cats, Oded; Jenelius, Erik et al

Poster (2020, January 12)

We introduce a rule based multiline holding criterion for regularity in branch and trunk networks accounting for all passenger groups. On the shared transit corridor, we consider synchronization at the ... [more ▼]

We introduce a rule based multiline holding criterion for regularity in branch and trunk networks accounting for all passenger groups. On the shared transit corridor, we consider synchronization at the merging or the diverging stop. The decision between holding for regularity or synchronization is taken by comparing the expected passenger cost of each control action. The proposed criterion is tested through simulation in a synthetic double fork network with different shares of transferring passengers, control schemes for regularity and synchronization. The results show that multiline control outperforms the state of the art schemes at the network level, stemming from benefits occurring at the first part of the route and the shared transit corridor and a 3.5% more stable joint headway compared to the other schemes. Additionally, it is advised to perform the synchronization at the diverging stop, as it proves to result in a more stable transferring time equal to the joint frequency of the corridor while reducing the transfer time variability up to -42.7%. [less ▲]

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See detailComprendre l'état du parlementarisme contemporain en Europe
Poirier, Philippe UL

in Le Parlement depuis 2008 : Renforcement, statu quo ou retour au(x) fondement(s) de la Ve République (2020, January 10)

Cet ouvrage reprend les actes du colloque d'Aix-en-Provence de 2018 consacré au bilan de dix ans de mise en oeuvre de la révision constitutionnelle de 2008 dans son volet parlementaire. Faisant intervenir ... [more ▼]

Cet ouvrage reprend les actes du colloque d'Aix-en-Provence de 2018 consacré au bilan de dix ans de mise en oeuvre de la révision constitutionnelle de 2008 dans son volet parlementaire. Faisant intervenir des acteurs de la révision de 2008, des parlementaires, des membres du Conseil constitutionnel, des hauts fonctionnaires des assemblées et des universitaires, ce colloque a été construit autour des trois fonctions essentielles du Parlement : l'élaboration de la loi, le contrôle de l'exécutif et l'évaluation des politiques publiques afin de répondre à cette question : un changement pour quoi faire ? [less ▲]

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See detailModeling for Three-Subset Division Property without Unknown Subset and Improved Cube Attacks
Hao, Yonglin; Leander, Gregor; Meier, Willi et al

in 39th Annual International Conference on the Theory and Applications of Cryptographic Techniques (EUROCRYPT 2020), Croatia 10-14 May 2020 (2020, January)

Detailed reference viewed: 42 (2 UL)
See detailAmbitious Amateurs - European Filmclubs in the long 1960s
Wack, Julia UL

Scientific Conference (2020, January)

Ambitious Amateurs aims to investigate the so-called mass taste through the lens of the participatory cultural practice of filming in the long 1960s. The filmmakers were consumers of a medium they were co ... [more ▼]

Ambitious Amateurs aims to investigate the so-called mass taste through the lens of the participatory cultural practice of filming in the long 1960s. The filmmakers were consumers of a medium they were co-creating themselves. They were producing for a circle of peers, respectively to get recognition from professionals. The aesthetic form of these films and genres, the excess of meaning, as well as the moral political ideals represent central axes of the analysis. Additionally, relations between the club members and their activities in national umbrella associations as well as contexts of transnational encounters (i.e. UNICA, founded in 1937) shall be further observed. This will be executed on the examples of selected clubs and locations in Luxembourg, Belgium, France and Germany. Besides archive research and Oral History, the film documents themselves are the core piece of the analysis. The topic is of particular relevance for general Culture and Media History, due to the historical evolution of censorship and auto-censorship tendencies regarding sexual permissiveness, political militancy or religious statements in the long 1960s. These will be connected with the issue of Americanisation, respectively the rejection of the latter within the discourse of European film creators and the topical press. The international comparison will additionally facilitate the display of national specificities and diverse temporalities within (Western)Europe. Simultaneously a possibility to conceive certain potential transnational developments – also beyond the ‘Iron Curtain’ – will be generated. [less ▲]

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See detailConditionality in the European Union External Migration Policy – A Critical Appraisal
Silga, Janine UL

Scientific Conference (2020, January)

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See detailCzechoslovak Jewish emigrants in the clutches of Luxembourg pre-war migration bureaucracy
Bronec, Jakub UL

in Malach Center for Visual History on its 10th Anniversary: Compendium of Papers of the Prague Visual History and Digital Humanities Conference 2020 (2020, January)

My contribution attempts to find answers to the following questions, among others: How did Luxembourg officials deal with Jewish refugees from Eastern European countries? Did the Luxembourgish authorities ... [more ▼]

My contribution attempts to find answers to the following questions, among others: How did Luxembourg officials deal with Jewish refugees from Eastern European countries? Did the Luxembourgish authorities distinguish or give priority to citizens of particular nations? Who was involved in the approval process? Who played the most active role and collected the most controversial information about Jewish immigrants? [less ▲]

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See detailDual-Use Research In Ransomware Attacks: A Discussion on Ransomware Defence Intelligence
Genç, Ziya Alper UL; Lenzini, Gabriele UL

in Proceedings of the 6th International Conference on Information Systems Security and Privacy (2020)

Previous research has shown that developers rely on public platforms and repositories to produce functional but insecure code. We looked into the matter for ransomware, enquiring whether also ransomware ... [more ▼]

Previous research has shown that developers rely on public platforms and repositories to produce functional but insecure code. We looked into the matter for ransomware, enquiring whether also ransomware engineers re-use the work of others and produce insecure code. By methodically reverse-engineering 128 malware executables, we have found that, out of 21 ransomware samples, 9 contain copy-paste code from public resources. Thanks to this finding, we managed to retrieve the decryption keys with which to nullify the ransomware attacks. From this fact, we recall critical cases of code disclosure in the recent history of ransomware and, arguing that ransomware are components in cyber-weapons, reflect on the dual-use nature of this research. We further discuss benefits and limits of using cyber-intelligence and counter-intelligence strategies that could be used against this threat. [less ▲]

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See detailLarge Intelligent Surface for Positioning in Millimeter Wave MIMO Systems
He, Jiguang; Wymeersch, Henk; Kong, Long UL et al

in 2020 IEEE 91st Vehicular Technology Conference (VTC2020-Spring) (2020)

Millimeter-wave (mmWave) multiple-input multiple-output (MIMO) system for the fifth generation (5G) cellular communications can also enable single-anchor positioning and object tracking due to its large ... [more ▼]

Millimeter-wave (mmWave) multiple-input multiple-output (MIMO) system for the fifth generation (5G) cellular communications can also enable single-anchor positioning and object tracking due to its large bandwidth and inherently high angular resolution. In this paper, we introduce the newly invented concept, large intelligent surface (LIS), to mmWave positioning systems, study the theoretical performance bounds (i.e., Cramér-Rao lower bounds) for positioning, and evaluate the impact of the number of LIS elements and the value of phase shifters on the position estimation accuracy compared to the conventional scheme with one direct link and one non-line-of-sight path. It is verified that better performance can be achieved with a LIS from the theoretical analyses and numerical study. [less ▲]

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See detailUnlinkable Updatable Databases and Oblivious Transfer with Access Control
Damodaran, Aditya Shyam Shankar UL; Rial, Alfredo UL

in 25th Australasian Conference on Information Security and Privacy (2020)

An oblivious transfer with access control protocol (OTAC) allows us to protect privacy of accesses to a database while enforcing access control policies. Existing OTAC have several shortcomings. First ... [more ▼]

An oblivious transfer with access control protocol (OTAC) allows us to protect privacy of accesses to a database while enforcing access control policies. Existing OTAC have several shortcomings. First, their design is not modular. Typically, to create an OTAC, an adaptive oblivious transfer protocol (OT) is extended ad-hoc. Consequently, the security of the OT is reanalyzed when proving security of the OTAC, and it is not possible to instantiate the OTAC with any secure OT. Second, existing OTAC do not allow for policy updates. Finally, in practical applications, many messages share the same policy. However, existing OTAC cannot take advantage of that to improve storage efficiency. We propose an UC-secure OTAC that addresses the aforementioned shortcomings. Our OTAC uses as building blocks the ideal functionalities for OT, for zero-knowledge (ZK) and for an \emph{unlinkable updatable database} ($\UUD$), which we define and construct. $\UUD$ is a protocol between an updater $\fuudUpdater$ and multiple readers $\fuudReader_k$. $\fuudUpdater$ sets up a database and updates it. $\fuudReader_k$ can read the database by computing UC ZK proofs of an entry in the database, without disclosing what entry is read. In our OTAC, $\UUD$ is used to store and read the policies. We construct an $\UUD$ based on subvector commitments (SVC). We extend the definition of SVC with update algorithms for commitments and openings, and we provide an UC ZK proof of a subvector. Our efficiency analysis shows that our $\UUD$ is practical. [less ▲]

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See detailUC Updatable Databases and Applications
Damodaran, Aditya Shyam Shankar UL; Rial, Alfredo UL

in 12th International Conference on Cryptology (2020)

We define an ideal functionality $\Functionality_{\UD}$ and a construction $\mathrm{\Pi_{\UD}}$ for an updatable database ($\UD$). $\UD$ is a two-party protocol between an updater and a reader. The ... [more ▼]

We define an ideal functionality $\Functionality_{\UD}$ and a construction $\mathrm{\Pi_{\UD}}$ for an updatable database ($\UD$). $\UD$ is a two-party protocol between an updater and a reader. The updater sets the database and updates it at any time throughout the protocol execution. The reader computes zero-knowledge (ZK) proofs of knowledge of database entries. These proofs prove that a value is stored at a certain position in the database, without revealing the position or the value. (Non-)updatable databases are implicitly used as building block in priced oblivious transfer, privacy-preserving billing and other privacy-preserving protocols. Typically, in those protocols the updater signs each database entry, and the reader proves knowledge of a signature on a database entry. Updating the database requires a revocation mechanism to revoke signatures on outdated database entries. Our construction $\mathrm{\Pi_{\UD}}$ uses a non-hiding vector commitment (NHVC) scheme. The updater maps the database to a vector and commits to the database. This commitment can be updated efficiently at any time without needing a revocation mechanism. ZK proofs for reading a database entry have communication and amortized computation cost independent of the database size. Therefore, $\mathrm{\Pi_{\UD}}$ is suitable for large databases. We implement $\mathrm{\Pi_{\UD}}$ and our timings show that it is practical. In existing privacy-preserving protocols, a ZK proof of a database entry is intertwined with other tasks, e.g., proving further statements about the value read from the database or the position where it is stored. $\Functionality_{\UD}$ allows us to improve modularity in protocol design by separating those tasks. We show how to use $\Functionality_{\UD}$ as building block of a hybrid protocol along with other functionalities. [less ▲]

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See detailHow to Develop a GDPR-Compliant Blockchain Solution for Cross-Organizational Workflow Management: Evidence from the German Asylum Procedure.
Guggenmos, F; Lockl, J; Rieger, A et al

in Proceedings of the Hawaii International Conference on System Sciences 2020 (2020)

Blockchain technology has the potential to resolve trust concerns in cross-organizational workflows and to reduce reliance on paper-based documents as trust anchors. Although these prospects are real, so ... [more ▼]

Blockchain technology has the potential to resolve trust concerns in cross-organizational workflows and to reduce reliance on paper-based documents as trust anchors. Although these prospects are real, so is regulatory uncertainty. In particular, the reconciliation of blockchain with Europe’s General Data Protection Regulation (GDPR) is proving to be a significant challenge. We tackled this challenge with the German Federal Office for Migration and Refugees. Here, we explain how we used Action Research to guide the Federal Office in creating a GDPR-compliant blockchain solution for the German asylum procedure. Moreover, we explain the architecture of the Federal Office’s solution and present two design principles for developing GDPR- compliant blockchain solutions for cross- organizational workflow management. [less ▲]

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See detailL’édition de chartes à Luxembourg: de l’érudition aux nouvelles technologies (et vice-versa?)
Salemme, Timothy UL

in Bendheim, Amelie (Ed.) Tagungsband Mittelalter zwischen Faszination und Fortschritt (2020)

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See detailAutomated Recommendation of Templates for Legal Requirements
Sleimi, Amin UL; Ceci, Marcello UL; Sabetzadeh, Mehrdad UL et al

in Proceedings of the 28th IEEE International Requirements Engineering Conference (RE'20) (2020)

[Context] In legal requirements elicitation, requirements analysts need to extract obligations from legal texts. However, legal texts often express obligations only indirectly, for example, by attributing ... [more ▼]

[Context] In legal requirements elicitation, requirements analysts need to extract obligations from legal texts. However, legal texts often express obligations only indirectly, for example, by attributing a right to the counterpart. This phenomenon has already been described in the Requirements Engineering (RE) literature. [Objectives] We investigate the use of requirements templates for the systematic elicitation of legal requirements. Our work is motivated by two observations: (1) The existing literature does not provide a harmonized view on the requirements templates that are useful for legal RE; (2) Despite the promising recent advancements in natural language processing (NLP), automated support for legal RE through the suggestion of requirements templates has not been achieved yet. Our objective is to take steps toward addressing these limitations. [Methods] We review and reconcile the legal requirement templates proposed in RE. Subsequently, we conduct a qualitative study to define NLP rules for template recommendation. [Results and Conclusions] Our contributions consist of (a) a harmonized list of requirements templates pertinent to legal RE, and (b) rules for the automatic recommendation of such templates. We evaluate our rules through a case study on 400 statements from two legal domains. The results indicate a recall and precision of 82,3% and 79,8%, respectively. We show that introducing some limited interaction with the analyst considerably improves accuracy. Specifically, our human-feedback strategy increases recall by 12% and precision by 10,8%, thus yielding an overall recall of 94,3% and overall precision of 90,6%. [less ▲]

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See detailComputational Metabolomics: From Cheminformatics to Machine Learning (Dagstuhl Seminar 20051)
Böcker, Sebastian; Broeckling, Corey; Schymanski, Emma UL et al

in Dagstuhl Reports (2020)

Dagstuhl Seminar 20051 on Computational Metabolomics is the third edition of seminars onthis topic and focused on Cheminformatics and Machine Learning. With the advent of higherprecision instrumentation ... [more ▼]

Dagstuhl Seminar 20051 on Computational Metabolomics is the third edition of seminars onthis topic and focused on Cheminformatics and Machine Learning. With the advent of higherprecision instrumentation, application of metabolomics to a wider variety of small molecules, andever increasing amounts of raw and processed data available, developments in cheminformaticsand machine learning are sorely needed to facilitate interoperability and leverage further insightsfrom these data. Following on from Seminars 17491 and 15492, this edition convened bothexperimental and computational experts, many of whom had attended the previous sessions andbrought much-valued perspective to the week’s proceedings and discussions. Throughout theweek, participants first debated on what topics to discuss in detail, before dispersing into smaller,focused working groups for more in-depth discussions. This dynamic format was found to bemost productive and ensured active engagement amongst the participants. The abstracts inthis report reflect these working group discussions, in addition to summarising several informalevening sessions. Action points to follow-up on after the seminar were also discussed, includingfuture workshops and possibly another Dagstuhl seminar in late 2021 or 2022. [less ▲]

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See detailCompetitive Evolution of a UAV Swarm for Improving Intruder Detection Rates
Stolfi Rosso, Daniel UL; Brust, Matthias R. UL; Danoy, Grégoire UL et al

in 2020 IEEE International Parallel and Distributed Processing Symposium Workshops, IPDPSW 2020, New Orleans, LA, USA, May 18-22, 2020 (2020)

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See detailMuteria: An Extensible and Flexible Multi-Criteria Software Testing Framework
Titcheu Chekam, Thierry UL; Papadakis, Mike UL; Le Traon, Yves UL

in ACM/IEEE International Conference on Automation of Software Test (AST) 2020 (2020)

Program based test adequacy criteria (TAC), such as statement, branch coverage and mutation give objectives for software testing. Many techniques and tools have been developed to improve each phase of the ... [more ▼]

Program based test adequacy criteria (TAC), such as statement, branch coverage and mutation give objectives for software testing. Many techniques and tools have been developed to improve each phase of the TAC-based software testing process. Nonetheless, The engineering effort required to integrate these tools and techniques into the software testing process limits their use and creates an overhead to the users. Especially for system testing with languages like C, where test cases are not always well structured in a framework. In response to these challenges, this paper presents Muteria, a TAC-based software testing framework. Muteria enables the integration of multiple software testing tools. Muteria abstracts each phase of the TAC-based software testing process to provide tool drivers interfaces for the implementation of tool drivers. Tool drivers enable Muteria to call the corresponding tools during the testing process. An initial set of drivers for KLEE, Shadow and SEMu test-generation tools, Gcov, and coverage.py code coverage tools, and Mart mutant generation tool for C and Python programming language were implemented with an average of 345 lines of Python code. Moreover, the user configuration file required to measure code coverage and mutation score on a sample C programs, using the Muteria framework, consists of less than 15 configuration variables. Users of the Muteria framework select, in a configuration file, the tools and TACs to measure. The Muteria framework uses the user configuration to run the testing process and report the outcome. Users interact with Muteria through its Application Programming Interface and Command Line Interface. Muteria can benefit to researchers as a laboratory to execute experiments, and to software practitioners. [less ▲]

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See detailDesign Challenges of Trustworthy Artificial Intelligence Learning Systems
Brust, Matthias R. UL; Bouvry, Pascal UL; Danoy, Grégoire UL et al

in Intelligent Information and Database Systems - 12th Asian Conference ACIIDS 2020, Phuket, Thailand, March 23-26, 2020, Companion Proceedings (2020)

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See detailIEEE Workshop on Parallel / Distributed Combinatorics and Optimization (PDCO 2020)
Danoy, Grégoire UL; Baz, Didier El; Boyer, Vincent et al

in 2020 IEEE International Parallel and Distributed Processing Symposium Workshops, IPDPSW 2020, New Orleans, LA, USA, May 18-22, 2020 (2020)

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See detailComparing Offline and Online Testing of Deep Neural Networks: An Autonomous Car Case Study
Ul Haq, Fitash UL; Shin, Donghwan UL; Nejati, Shiva UL et al

in 13th IEEE International Conference on Software Testing, Verification and Validation (ICST) 2020 (2020)

There is a growing body of research on developing testing techniques for Deep Neural Networks (DNN). We distinguish two general modes of testing for DNNs: Offline testing where DNNs are tested as ... [more ▼]

There is a growing body of research on developing testing techniques for Deep Neural Networks (DNN). We distinguish two general modes of testing for DNNs: Offline testing where DNNs are tested as individual units based on test datasets obtained independently from the DNNs under test, and online testing where DNNs are embedded into a specific application and tested in a close-loop mode in interaction with the application environment. In addition, we identify two sources for generating test datasets for DNNs: Datasets obtained from real-life and datasets generated by simulators. While offline testing can be used with datasets obtained from either sources, online testing is largely confined to using simulators since online testing within real-life applications can be time consuming, expensive and dangerous. In this paper, we study the following two important questions aiming to compare test datasets and testing modes for DNNs: First, can we use simulator-generated data as a reliable substitute to real-world data for the purpose of DNN testing? Second, how do online and offline testing results differ and complement each other? Though these questions are generally relevant to all autonomous systems, we study them in the context of automated driving systems where, as study subjects, we use DNNs automating end-to-end control of cars' steering actuators. Our results show that simulator-generated datasets are able to yield DNN prediction errors that are similar to those obtained by testing DNNs with real-life datasets. Further, offline testing is more optimistic than online testing as many safety violations identified by online testing could not be identified by offline testing, while large prediction errors generated by offline testing always led to severe safety violations detectable by online testing. [less ▲]

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See detailMeeting Designers Where They Are: Using Industry Events as a Research Venue for HCI and Design Methods Development
Lockton, Dan; Lallemand, Carine UL

Scientific Conference (2020)

There is much work in the CHI community about the ‘industry-academia divide’, and how to bridge it. One key crossover between HCI/UX scientists and practitioners is the development and use of tools and ... [more ▼]

There is much work in the CHI community about the ‘industry-academia divide’, and how to bridge it. One key crossover between HCI/UX scientists and practitioners is the development and use of tools and methods—boundary objects between academia and practice. Among other forms of collaboration, there is an underdeveloped opportunity for academics to make use of industry events (conferences, meetups, design jams) as a research venue in the context of tool and method development. This paper describes three cases from work in academia-industry engagement over the last decade, in which workshops or experiments have been run at industry events as a way of trialling and developing tools directly with practitioners. We discuss advantages of this approach and extract key insights and practical implications, highlighting how the CHI community might use this method more widely, gathering relevant research outcomes while contributing to knowledge exchange between academia and practice. [less ▲]

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See detailTracking Hurricanes using GPS atmospheric precipitable water vapor field
Ejigu, Yohannes Getachew; Teferle, Felix Norman UL; klos, Anna et al

in Beyond 100: The Next Century in Geodesy (2020)

Tropical cyclones are one of the most powerful severe weather events that produce devastating socioeconomic and environmental impacts in the areas they strike. Therefore, monitoring and tracking of the ... [more ▼]

Tropical cyclones are one of the most powerful severe weather events that produce devastating socioeconomic and environmental impacts in the areas they strike. Therefore, monitoring and tracking of the arrival times and path of the tropical cyclones are extremely valuable in providing early warning to the public and governments. Hurricane Florence struck the East cost of USA in 2018 and offers an outstanding case study. We employed Global Positioning System (GPS) derived precipitable water vapor (PWV) data to track and investigate the characteristics of storm occurrences in their spatial and temporal distribution using a dense ground network of permanent GPS stations. Our findings indicate that a rise in GPS-derived PWV occurred several hours before Florence’s manifestation. Also, we compared the temporal distribution of the GPS-derived PWV content with the precipitation value for days when the storm appeared in the area under influence. The study will contribute to quantitative assessment of the complementary GPS tropospheric products in hurricane monitoring and tracking using GPS-derived water vapor evolution from a dense network of permanent GPS stations [less ▲]

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See detailOptimizing the Performance of an Unpredictable UAV Swarm for Intruder Detection
Stolfi Rosso, Daniel UL; Brust, Matthias R. UL; Danoy, Grégoire UL et al

in Optimization and Learning - Third International Conference, OLA 2020, Cádiz, Spain, February 17-19, 2020, Proceedings (2020)

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See detailSMRL: A Metamorphic Security Testing Tool for Web Systems
Mai, Xuan Phu UL; Göknil, Arda; Pastore, Fabrizio UL et al

in 2020 IEEE/ACM 42nd International Conference on Software Engineering (2020)

We present a metamorphic testing tool that alleviates the oracle problem in security testing. The tool enables engineers to specify metamorphic relations that capture security properties of Web systems ... [more ▼]

We present a metamorphic testing tool that alleviates the oracle problem in security testing. The tool enables engineers to specify metamorphic relations that capture security properties of Web systems. It automatically tests Web systems to detect vulnerabilities based on those relations. We provide a domain-specific language accompanied by an Eclipse editor to facilitate the specification of metamorphic relations. The tool automatically collects the input data and transforms the metamorphic relations into executable Java code in order to automatically perform security testing based on the collected data. The tool has been successfully evaluated on a commercial system and a leading open source system (Jenkins). Demo video: https://youtu.be/9kx6u9LsGxs. [less ▲]

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See detailGesonderte Ruhestätten für besondere Tote: Soldatengräber und Garnisonsfriedhöfe unter besonderer Berücksichtigung der Entwicklung in Luxemburg
Kolnberger, Thomas UL

in Loew, Benedikt; Thewes, Guy; Klauck, Hans Peter (Eds.) Intra muros - Infrastruktur und Lebensalltag in Festungen - Einrichtungen der Fürsorge (2020)

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See detailÆGIS: Shielding Vulnerable Smart Contracts Against Attacks
Ferreira Torres, Christof UL; Steichen, Mathis UL; Norvill, Robert UL et al

in Proceedings of the 15th ACM Asia Conference on Computer and Communications Security (ASIA CCS ’20), October 5–9, 2020, Taipei, Taiwan (2020)

In recent years, smart contracts have suffered major exploits, cost- ing millions of dollars. Unlike traditional programs, smart contracts are deployed on a blockchain. As such, they cannot be modified ... [more ▼]

In recent years, smart contracts have suffered major exploits, cost- ing millions of dollars. Unlike traditional programs, smart contracts are deployed on a blockchain. As such, they cannot be modified once deployed. Though various tools have been proposed to detect vulnerable smart contracts, the majority fails to protect vulnera- ble contracts that have already been deployed on the blockchain. Only very few solutions have been proposed so far to tackle the issue of post-deployment. However, these solutions suffer from low precision and are not generic enough to prevent any type of attack. In this work, we introduce ÆGIS, a dynamic analysis tool that protects smart contracts from being exploited during runtime. Its capability of detecting new vulnerabilities can easily be extended through so-called attack patterns. These patterns are written in a domain-specific language that is tailored to the execution model of Ethereum smart contracts. The language enables the description of malicious control and data flows. In addition, we propose a novel mechanism to streamline and speed up the process of managing attack patterns. Patterns are voted upon and stored via a smart contract, thus leveraging the benefits of tamper-resistance and transparency provided by the blockchain. We compare ÆGIS to current state-of-the-art tools and demonstrate that our solution achieves higher precision in detecting attacks. Finally, we perform a large-scale analysis on the first 4.5 million blocks of the Ethereum blockchain, thereby confirming the occurrences of well reported and yet unreported attacks in the wild. [less ▲]

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See detailJoint Power Allocation and Access Point Selection for Cell-free Massive MIMO
Vu, Thang Xuan UL; Chatzinotas, Symeon UL; ShahbazPanahi, Shahram et al

in IEEE International Conference on Communications (2020)

Cell-free massive multiple-input multiple-output (CF-MIMO) is a promising technological enabler for fifth generation (5G) networks in which a large number of access points (APs) jointly serve the users ... [more ▼]

Cell-free massive multiple-input multiple-output (CF-MIMO) is a promising technological enabler for fifth generation (5G) networks in which a large number of access points (APs) jointly serve the users. Each AP applies conjugate beamforming to precode data, which is based only on the AP's local channel state information. However, by having the nature of a (very) large number of APs, the operation of CF-MIMO can be energy-inefficient. In this paper, we investigate the energy efficiency performance of CF-MIMO by considering a practical energy consumption model which includes both the signal transmit energy as well as the static energy consumed by hardware components. In particular, a joint power allocation and AP selection design is proposed to minimize the total energy consumption subject to given quality of service (QoS) constraints. In order to deal with the combinatorial complexity of the formulated problem, we employ norm $l_{2,1}$-based block-sparsity and successive convex optimization to leverage the AP selection process. Numerical results show significant energy savings obtained by the proposed design, compared to all-active APs scheme and the large-scale based AP selection. [less ▲]

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See detailCoercion-Resistant Voting in Linear Time via Fully Homomorphic Encryption: Towards a Quantum-Safe Scheme
Roenne, Peter UL; Atashpendar, Arash UL; Kristian, Gjøsteen et al

in Financial Cryptography and Data Security 2019. FC 2019: International Workshops, CIW, VOTING, and WTSC (2020)

We present an approach for performing the tallying work in the coercion-resistant JCJ voting protocol, introduced by Juels, Catalano, and Jakobsson, in linear time using fully homomorphic encryption (FHE ... [more ▼]

We present an approach for performing the tallying work in the coercion-resistant JCJ voting protocol, introduced by Juels, Catalano, and Jakobsson, in linear time using fully homomorphic encryption (FHE). The suggested enhancement also paves the path towards making JCJ quantum-resistant, while leaving the underlying structure of JCJ intact. The pairwise comparison-based approach of JCJ using plaintext equivalence tests leads to a quadratic blow-up in the number of votes, which makes the tallying process rather impractical in realistic settings with a large number of voters. We show how the removal of invalid votes can be done in linear time via a solution based on recent advances in various FHE primitives such as hashing, zero-knowledge proofs of correct decryption, verifiable shuffles and threshold FHE. We conclude by touching upon some of the advantages and challenges of such an approach, followed by a discussion of further security and post-quantum considerations. [less ▲]

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See detailNGAP: a novel hybrid metaheuristic algorithm for round-trip carsharing fleet planning
Changaival, Boonyarit UL; Danoy, Grégoire UL; Kliazovich et al

in GECCO '20: Genetic and Evolutionary Computation Conference, Companion Volume, Cancún, Mexico, July 8-12, 2020 (2020)

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See detailA Cooperative Coevolutionary Approach to Maximise Surveillance Coverage of UAV Swarms
Stolfi Rosso, Daniel UL; Brust, Matthias R. UL; Danoy, Grégoire UL et al

in IEEE 17th Annual Consumer Communications & Networking Conference CCNC 2020, Las Vegas, NV, USA, January 10-13, 2020 (2020)

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See detailAdversarial Embedding: A robust and elusive Steganography and Watermarking technique
Ghamizi, Salah UL; Cordy, Maxime UL; Papadakis, Mike UL et al

Scientific Conference (2020)

We propose adversarial embedding, a new steganography and watermarking technique that embeds secret information within images. The key idea of our method is to use deep neural networks for image ... [more ▼]

We propose adversarial embedding, a new steganography and watermarking technique that embeds secret information within images. The key idea of our method is to use deep neural networks for image classification and adversarial attacks to embed secret information within images. Thus, we use the attacks to embed an encoding of the message within images and the related deep neural network outputs to extract it. The key properties of adversarial attacks (invisible perturbations, nontransferability, resilience to tampering) offer guarantees regarding the confidentiality and the integrity of the hidden messages. We empirically evaluate adversarial embedding using more than 100 models and 1,000 messages. Our results confirm that our embedding passes unnoticed by both humans and steganalysis methods, while at the same time impedes illicit retrieval of the message (less than 13% recovery rate when the interceptor has some knowledge about our model), and is resilient to soft and (to some extent) aggressive image tampering (up to 100% recovery rate under jpeg compression). We further develop our method by proposing a new type of adversarial attack which improves the embedding density (amount of hidden information) of our method to up to 10 bits per pixel. [less ▲]

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See detailMaking Encryption Feel Secure: Investigating how Descriptions of Encryption Impact Perceived Security
Distler, Verena UL; Lallemand, Carine UL; Koenig, Vincent UL

in The 5th European Workshop on Usable Security (EuroUSEC 2020) (2020)

When communication about security to end users is ineffective, people frequently misinterpret the protection offered by a system. The discrepancy between the security users perceive a system to have and ... [more ▼]

When communication about security to end users is ineffective, people frequently misinterpret the protection offered by a system. The discrepancy between the security users perceive a system to have and the actual system state can lead to potentially risky behaviors. It is thus crucial to understand how security perceptions are shaped by interface elements such as text-based descriptions of encryption. This article addresses the question of how encryption should be described to non-experts in a way that enhances perceived security. We tested the following within-subject variables in an online experiment (N=309): a) how to best word encryption, b) whether encryption should be described with a focus on the process or outcome, or both c) whether the objective of encryption should be mentioned d) when mentioning the objective of encryption, how to best describe it e) whether a hash should be displayed to the user. We also investigated the role of context (between subjects). The verbs “encrypt” and “secure” performed comparatively well at enhancing perceived security. Overall, participants stated that they felt more secure not knowing about the objective of encryption. When it is necessary to state the objective, positive wording of the objective of encryption worked best. We discuss implications and why using these results to design for perceived lack of security might be of interest as well. This leads us to discuss ethical concerns, and we give guidelines for the design of user interfaces where encryption should be communicated to end users. [less ▲]

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See detailSecurity and Privacy in Resource-Constrained Devices
Chiara, Pier Giorgio UL

in CEUR Workshop Proceedings (2020), 2598

Recent adversarial attacks have been shown IoT devices weaknesses due to their limited computing power. Given also their ubiquitous presence, lower costs and limitations in keeping security measures up ... [more ▼]

Recent adversarial attacks have been shown IoT devices weaknesses due to their limited computing power. Given also their ubiquitous presence, lower costs and limitations in keeping security measures up-todate, resource-constrained devices represent a growing risk for the security of IT infrastructure. The scope of the research is to investigate the weaknesses of resource-constrained IoT devices. The methodology for the investigation is the legal analysis of existing legal frameworks regulating IoT cybersecurity and data security; afterwards it will be carried out a critical evaluation of the existing best practices. This critical analysis should face the twofold challenge of increasing transparency and trust in resource-constrained systems. Users and companies are two faces of the same coin: accountability of data collectors and user awareness are crucial in the security and data protection debate. Thus, a comprehensive overview of the relevant legal frameworks and guidelines would increase the understanding of risks of the users, whilst data controllers (especially of small and medium enterprises) may have an instrument to implement properly security measures. [less ▲]

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See detailAttack-Tree Series: A Case for Dynamic Attack Tree Analysis
Gadyatskaya, Olga UL; Mauw, Sjouke UL

in Proc.\ 6th International Workshop on Graphical Models for Security (GraMSec'19) (2020)

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See detailCarrier and Power Assignment for Flexible Broadband GEO Satellite Communications System
Abdu, Tedros Salih UL; Lagunas, Eva UL; Kisseleff, Steven et al

in PIMRC 2020 Proceedings (2020)

Current multi-beam GEO satellite systems operate under a limited frequency reuse configuration and considering uniform power assignment across beams. The latter has been shown to be inefficient in ... [more ▼]

Current multi-beam GEO satellite systems operate under a limited frequency reuse configuration and considering uniform power assignment across beams. The latter has been shown to be inefficient in matching the geographic distribution of the traffic demand. In this context, next generation of broadband GEO satellite systems will be equipped with more flexible and reconfigurable payloads, facilitating on-demand resource allocation. In this paper, we consider both carrier and power assignment to match the requested beam demands while minimizing the total transmit power and the total utilized bandwidth. A novel optimization problem is formulated and, given its non-convex structure, we divide the problem into two tractable sub-problems. First, we estimate the number of adjacent frequency carriers required for each beam to satisfy its demand and, subsequently, we optimize the power allocation based on the previously assigned carriers. We validate the proposed method with extensive numerical results, which demonstrate its efficiency with respect to benchmark strategies. [less ▲]

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See detailEvaluating ambiguity of privacy indicators in a secure email app
Stojkovski, Borce UL; Lenzini, Gabriele UL

in Loreti, Michele; Spalazzi, Luca (Eds.) Proceedings of the Fourth Italian Conference on Cyber Security, Ancona Italy, February 4th to 7th, 2020 (2020)

Informing laymen of security situations is a notoriously hard problem. Users are usually not cognoscenti of all the various secure and insecure situations that may arise, and this can be further worsened ... [more ▼]

Informing laymen of security situations is a notoriously hard problem. Users are usually not cognoscenti of all the various secure and insecure situations that may arise, and this can be further worsened by certain visual indicators that instead of helping users, fail to convey clear and unambiguous messages. Even in well-established and studied applications, like email clients providing end-to-end encryption, the problem seems far from being solved. Motivated to verify this claim, we studied the communication qualities of four privacy icons (in the form of coloured shapes) in conveying specific security messages, relevant for a particular secure emailing system called p≡p. We questioned 42 users in three different sessions, where we showed them 10 privacy ratings, along with their explanations, and asked them to match the rating and explanation with the four privacy icons. We compared the participants’ associations to those made by the p≡p developers. The results, still preliminary, are not encouraging. Except for the two most extreme cases, Secure and trusted and Under attack, users almost entirely missed to get the indicators’ intended messages. In particular, they did not grasp certain concepts such as Unsecure email and Secure email, which in turn were fundamental for the engineers. Our work has certain limitations and further investigation is required, but already at this stage our research calls for a closer collaboration between app engineers and icon designers. In the context of p≡p, our work has triggered a deeper discussion on the icon design choices and a potential revamp is on the way. [less ▲]

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See detailDeepVI: A Novel Framework for Learning Deep View-Invariant Human Action Representations using a Single RGB Camera
Papadopoulos, Konstantinos UL; Ghorbel, Enjie UL; Oyedotun, Oyebade UL et al

in IEEE International Conference on Automatic Face and Gesture Recognition, Buenos Aires 18-22 May 2020 (2020)

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See detailAutomated design of efficient swarming behaviours: a Q-learning hyper-heuristic approach
Duflo, Gabriel UL; Danoy, Grégoire UL; Talbi, El-Ghazali UL et al

in GECCO '20: Genetic and Evolutionary Computation Conference, Companion Volume, Cancún, Mexico, July 8-12, 2020 (2020)

Detailed reference viewed: 10 (0 UL)
See detailMale knjizevnosti: pregled pojmov
Glesener, Jeanne E UL

in Koron, Alenka; Leben, Andrej (Eds.) Literarna vecjezicnost v slovenskem in avstrijskem konteksti (2020)

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See detailVisualisierungen des Induktionsprinzips
Perucca, Antonella UL; Todorovic, Milko

in Beiträge zum Mathematikunterricht 2020 (2020)

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See detailKummer theory for number fields
Perucca, Antonella UL; Sgobba, Pietro UL; Tronto, Sebastiano UL

in Proceedings of the Roman Number Theory Association (2020)

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See detailAutomatic Testing and Improvement of Machine Translation
Sun, Zeyu; Zhang, Jie; Harman, Mark et al

in International Conference on Software Engineering (ICSE) (2020)

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See detailA Worst-Case Performance Optimization Based Design Approach to Robust Symbol-Level Precoding for Downlink MU-MIMO
Haqiqatnejad, Alireza UL; Shahbazpanahi, Shahram UL; Ottersten, Björn UL

in IEEE Global Conference on Signal and Information Processing (GlobalSIP), Ottawa 11-14 November 2019 (2020)

This paper addresses the optimization problem of symbol-level precoding (SLP) in the downlink of a multiuser multiple-input multiple-output (MU-MIMO) wireless system while the precoder's output is subject ... [more ▼]

This paper addresses the optimization problem of symbol-level precoding (SLP) in the downlink of a multiuser multiple-input multiple-output (MU-MIMO) wireless system while the precoder's output is subject to partially-known distortions. In particular, we assume a linear distortion model with bounded additive noise. The original signal-to-interference- plus-noise ratio (SINR) -constrained SLP problem minimizing the total transmit power is first reformulated as a penalized unconstrained problem, which is referred to as the relaxed robust formulation. We then adopt a worst-case design approach to protect the users' intended symbols and the targeted constructive interference with a desired level of confidence. Due to the non-convexity of the relaxed robust formulation, we propose an iterative algorithm based on the block coordinate ascent-descent method. We show through simulation results that the proposed robust design is flexible in the sense that the CI constraints can be relaxed so as to keep a desirable balance between achievable rate and power consumption. Remarkably, the new formulation yields more energy-efficient solutions for appropriate choices of the relaxation parameter, compared to the original problem. [less ▲]

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See detailAutonomous Flight of Unmanned Aerial Vehicles Using Evolutionary Algorithms
Gaudín, Américo; Madruga, Gabriel; Rodríguez, Carlos et al

in High Performance Computing (2020)

This article explores the application of evolutionary algorithms and agent-oriented programming to solve the problem of searching and monitoring objectives through a fleet of unmanned aerial vehicles. The ... [more ▼]

This article explores the application of evolutionary algorithms and agent-oriented programming to solve the problem of searching and monitoring objectives through a fleet of unmanned aerial vehicles. The subproblem of static off-line planning is studied to find initial flight plans for each vehicle in the fleet, using evolutionary algorithms to achieve compromise values between the size of the explored area, the proximity of the vehicles, and the monitoring of points of interest defined in the area. The results obtained in the experimental analysis on representative instances of the surveillance problem indicate that the proposed techniques are capable of computing effective flight plans. [less ▲]

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See detailBorder-Making and its Consequences: A Global Overview.
Venken, Machteld UL; Fellner, Astrid; Dorfman, Adriana et al

in Eurasia Border Review (2020), 10(1), 59-69

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See detailUnderstanding Walking Meetings: Drivers and Barriers
Damen, Ida; Lallemand, Carine UL; Brankaert, Rens et al

Scientific Conference (2020)

There is increased interest in reducing sedentary behavior of office workers to combat the negative health effects of prolonged sitting. Walking meetings offer a promising solution to this problem as they ... [more ▼]

There is increased interest in reducing sedentary behavior of office workers to combat the negative health effects of prolonged sitting. Walking meetings offer a promising solution to this problem as they facilitate a physically active way of working. To inform future development of technologies supporting these type of meetings, in-depth qualitative insights into people’s experiences of walking meetings are needed. We conducted semi-structured walking interviews (N=16) to identify key drivers and barriers for walking meetings in a living lab setting by using the ‘WorkWalk’. The ‘WorkWalk’ is a 1.8 km walking route indicated by a dotted blue line with outdoor meeting points, integrated into the room booking system. Our findings provide insights into how walking meetings are experienced and affect the set-up and social dynamics of meetings. We propose design recommendations for the development of future technologies and service design elements to support walking meetings and active ways of working. [less ▲]

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See detailA Look into Privacy-Preserving Blockchains
Khan, Nida UL; Nassar, Mohamed

in IEEE BCA @AICCSA 2019 - Workshop on Blockchain and it's Applications (2020)

Blockchain is a revolutionary technology promising a new generation of decentralized, transparent and tamper-proof database systems. However, one of the main challenges of the emerging blockchain systems ... [more ▼]

Blockchain is a revolutionary technology promising a new generation of decentralized, transparent and tamper-proof database systems. However, one of the main challenges of the emerging blockchain systems remains to address data privacy. While in Bitcoin and similar e-cash systems, privacy was limited to anonymity and addressed by using cryptographic pseudonyms for identification and authentication of parties, the question of privacy has more breadth in systems maintaining actual data such as medical records or energy meters. In this paper, we look into recently proposed privacy-preserving blockchains, analyze their strengths and weaknesses, and highlight research questions requiring future investigation. We conclude that privacy-preserving blockchains are still in their infancy and more research is definitely needed in this area. [less ▲]

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See detailMachine Learning to Geographically Enrich Understudied Sources: A Conceptual Approach
Viola, Lorella UL; Verheul, Jaap

in Rocha, Ana; Steels, Luc; van den Herik, Jaap (Eds.) Proceedings of the 12th International Conference on Agents and Artificial Intelligence - Volume 1: ARTIDIGH (2020)

This paper discusses the added value of applying machine learning (ML) to contextually enrich digital collections. In this study, we employed ML as a method to geographically enrich historical datasets ... [more ▼]

This paper discusses the added value of applying machine learning (ML) to contextually enrich digital collections. In this study, we employed ML as a method to geographically enrich historical datasets. Specifically, we used a sequence tagging tool (Riedl and Padó 2018) which implements TensorFlow to perform NER on a corpus of historical immigrant newspapers. Afterwards, the entities were extracted and geocoded. The aim was to prepare large quantities of unstructured data for a conceptual historical analysis of geographical references. The intention was to develop a method that would assist researchers working in spatial humanities, a recently emerged interdisciplinary field focused on geographic and conceptual space. Here we describe the ML methodology and the geocoding phase of the project, focussing on the advantages and challenges of this approach, particularly for humanities scholars. We also argue that, by choosing to use largely neglected sources such as immigrant newspapers (a lso known as ethnic newspapers), this study contributes to the debate about diversity representation and archival biases in digital practices. [less ▲]

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See detailThe low-dimensional algebraic cohomology of the Witt and the Virasoro algebra with values in natural modules
Ecker, Jill Marie-Anne UL; Schlichenmaier, Martin UL

in Banach Center Publications (2020)

The main aim of this contribution is to compute the low-dimensional algebraic cohomology of the Witt and the Virasoro algebra with values in the adjoint and the trivial module. The last section includes ... [more ▼]

The main aim of this contribution is to compute the low-dimensional algebraic cohomology of the Witt and the Virasoro algebra with values in the adjoint and the trivial module. The last section includes results for the general tensor densities modules, presented without proof. One of our main results is that the third algebraic cohomology of the Witt algebra with values in the adjoint module vanishes, while it is one-dimensional for the Virasoro algebra. The first and the second algebraic cohomology of the Witt and the Virasoro algebra with values in tensor densities modules vanish for almost all modules. In the case they do not vanish, we give explicit expressions for the generating cocycles. In our work, we consider algebraic cohomology and not only the sub-complex of continuous cohomology, meaning we do not put any continuity constraints on the cochains. Consequently, our results are independent of any choice of an underlying topology, and valid for any concrete realizations of the considered Lie algebras. [less ▲]

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See detailAuthentication and Key Management Automation in Decentralized Secure Email and Messaging via Low-Entropy Secrets
Vazquez Sandoval, Itzel UL; Atashpendar, Arash; Lenzini, Gabriele UL

in Proceedings of the 17th International Joint Conference on e-Business and Telecommunications (2020)

We revisit the problem of entity authentication in decentralized end-to-end encrypted email and secure messaging to propose a practical and self-sustaining cryptographic solution based on password ... [more ▼]

We revisit the problem of entity authentication in decentralized end-to-end encrypted email and secure messaging to propose a practical and self-sustaining cryptographic solution based on password-authenticated key exchange (PAKE). This not only allows users to authenticate each other via shared low-entropy secrets, e.g., memorable words, without a public key infrastructure or a trusted third party, but it also paves the way for automation and a series of cryptographic enhancements; improves security by minimizing the impact of human error and potentially improves usability. First, we study a few vulnerabilities in voice-based out-of-band authentication, in particular a combinatorial attack against lazy users, which we analyze in the context of a secure email solution. Next, we propose solving the problem of secure equality test using PAKE to achieve entity authentication and to establish a shared high-entropy secret key. Our solution lends itself to offline settings, compatible with the inherently asynchronous nature of email and modern messaging systems. The suggested approach enables enhancements in key management such as automated key renewal and future key pair authentications, multi-device synchronization, secure secret storage and retrieval, and the possibility of post-quantum security as well as facilitating forward secrecy and deniability in a primarily symmetric-key setting. We also discuss the use of auditable PAKEs for mitigating a class of online guess and abort attacks in authentication protocols. [less ▲]

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See detailTowards Usable Protection Against Honeypots
Ferreira Torres, Christof UL; Steichen, Mathis UL; State, Radu UL

in IEEE International Conference on Blockchain and Cryptocurrency, Toronto, Canada 3-6 May 2020 (2020)

The Ethereum blockchain enables the execution of so-called smart contracts. These are programs that facilitate the automated transfer of funds according to a given business logic without the participants ... [more ▼]

The Ethereum blockchain enables the execution of so-called smart contracts. These are programs that facilitate the automated transfer of funds according to a given business logic without the participants requiring to trust one another. However, recently attackers started using smart contracts to lure users into traps by deploying contracts that pretend to give away funds but in fact contain hidden traps. This new type of scam is commonly referred to as honeypots. In this paper, we propose a system that aims to protect users from falling into these traps. The system consists of a plugin for MetaMask and a back-end service that continuously scans the Ethereum blockchain for honeypots. Whenever a user is about to perform a transaction through MetaMask, our plugin sends a request to the back-end and warns the user if the target contract is a honeypot. [less ▲]

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See detailApproximation-Refinement Testing of Compute-Intensive Cyber-Physical Models: An Approach Based on System Identification
Menghi, Claudio UL; Nejati, Shiva UL; Briand, Lionel UL et al

in Proceedings of the 42nd International Conference on Software Engineering (2020)

Black-box testing has been extensively applied to test models of Cyber-Physical systems (CPS) since these models are not often amenable to static and symbolic testing and verification. Black-box testing ... [more ▼]

Black-box testing has been extensively applied to test models of Cyber-Physical systems (CPS) since these models are not often amenable to static and symbolic testing and verification. Black-box testing, however, requires to execute the model under test for a large number of candidate test inputs. This poses a challenge for a large and practically-important category of CPS models, known as compute-intensive CPS (CI-CPS) models, where a single simulation may take hours to complete. We propose a novel approach, namely ARIsTEO, to enable effective and efficient testing of CI-CPS models. Our approach embeds black-box testing into an iterative approximation-refinement loop. At the start, some sampled inputs and outputs of the CI-CPS model under test are used to generate a surrogate model that is faster to execute and can be subjected to black-box testing. Any failure-revealing test identified for the surrogate model is checked on the original model. If spurious, the test results are used to refine the surrogate model to be tested again. Otherwise, the test reveals a valid failure. We evaluated ARIsTEO by comparing it with S-Taliro, an open-source and industry-strength tool for testing CPS models. Our results, obtained based on five publicly-available CPS models, show that, on average, ARIsTEO is able to find 24% more requirements violations than S-Taliro and is 31% faster than S-Taliro in finding those violations. We further assessed the effectiveness and efficiency of ARIsTEO on a large industrial case study from the satellite domain. In contrast to S-Taliro, ARIsTEO successfully tested two different versions of this model and could identify three requirements violations, requiring four hours, on average, for each violation. [less ▲]

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