References of "Scientific congresses, symposiums and conference proceedings"
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See detailLa force intégrative du statut de l'Etat membre sur la fonction juridictionnelle
Neframi, Eleftheria UL

in Potvin Solis, Laurence (Ed.) Le statut d'Etat membre de l'Union européenne (in press)

The integrative force of the Member States’ status on the judicial function is expressed through the loyalty obligation to provide remedies sufficient to ensure effective legal protection in the fields ... [more ▼]

The integrative force of the Member States’ status on the judicial function is expressed through the loyalty obligation to provide remedies sufficient to ensure effective legal protection in the fields covered by Union law (Art 19, par 1, subpar 2, TEU). Member States have to ensure access to the national judge, who has been entrusted with a European mandate, and who is in measure to cooperate with the Court of Justice through the preliminary reference procedure. The Member States establish in this way an integrated judicial function. The exercise of such a function by the national judge, in cooperation with the Court of Justice and under the control of the Member State, implies integrative dynamic, which however depends on the balancing exercise with national procedural autonomy and the margin of appreciation of the national judge. [less ▲]

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See detailSupporting Security Protocols on CAN-Based Networks
Bloom, Gedare; Cena, Gianlua; Cibrario Bertolotti, Ivan et al

Scientific Conference (in press)

The ever-increasing variety of services built on top of the Controller Area Network (CAN), along with the recent discovery of vulnerabilities in CAN-based automotive systems (some of them demonstrated in ... [more ▼]

The ever-increasing variety of services built on top of the Controller Area Network (CAN), along with the recent discovery of vulnerabilities in CAN-based automotive systems (some of them demonstrated in practice) stimulated a renewed attention to security-oriented enhancements of the CAN protocol. The issue is further compounded nowadays because, unlike in the past, security can no longer be enforced by physical bus segregation. This paper describes how CAN XR, a recently proposed extension of the CAN data-link layer, can effectively support the distributed calculation of arbitrary binary Boolean functions, which are the foundation of most security protocols, without necessarily disclosing their operands on the bus. The feasibility of the approach is then shown through experimental evaluation and by confirming its applicability to a shared key generation protocol proposed in literature. [less ▲]

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See detailA New Perspective on the Luxembourgish Genitive
Döhmer, Caroline UL

in Germanic Genitives (in press)

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See detailService Performance Pattern Analysis and Prediction of Commercially Available Cloud Providers
Wagle, Shyam Sharan UL; Guzek, Mateusz UL; Bouvry, Pascal UL

in Service Performance Pattern Analysis and Prediction of Commercially Available Cloud Providers (in press)

The knowledge of service performance of cloud providers is essential for cloud service users to choose the cloud services that meet their requirements. Instantaneous performance readings are accessible ... [more ▼]

The knowledge of service performance of cloud providers is essential for cloud service users to choose the cloud services that meet their requirements. Instantaneous performance readings are accessible, but prolonged observations provide more reliable information. However, due to technical complexities and costs of monitoring services, it may not be possible to access the service performance of cloud provider for longer time durations. The extended observation periods are also a necessity for prediction of future behavior of services. These predictions have very high value for decision making both for private and corporate cloud users, as the uncertainty about the future performance of purchased cloud services is an important risk factor. Predictions can be used by specialized entities, such as cloud service brokers (CSBs) to optimally recommend cloud services to the cloud users. In this paper, we address the challenge of prediction. To achieve this, the current service performance patterns of cloud providers are analyzed and future performance of cloud providers are predicted using to the observed service performance data. It is done using two automatic predicting approaches: ARIMA and ETS. Error measures of entire service performance prediction of cloud providers are evaluated against the actual performance of the cloud providers computed over a period of one month. Results obtained in the performance prediction show that the methodology is applicable for both short- term and long-term performance prediction. [less ▲]

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See detailComparing automated visual GUI testing tools: an industrial case study
Garousi, Vahid UL; Afzal, Wasif; Çağlar, Adem et al

in Proceedings of International Workshop on Automated Software Testing (A-TEST) (in press)

Visual GUI testing (VGT) is a tool-driven technique, which uses image recognition for interaction and assertion of the behaviour of system under test. Motivated by a real industrial need, in the context ... [more ▼]

Visual GUI testing (VGT) is a tool-driven technique, which uses image recognition for interaction and assertion of the behaviour of system under test. Motivated by a real industrial need, in the context of a large Turkish software and systems company providing solutions in the areas of defense and IT sector, we systematically planned and applied a VGT project in this industrial context. The goal of the initial phase of the project was to empirically evaluate two well-known VGT tools (Sikuli and JAutomate) to help the company select the best tool for a given testing project. Our results show that both two tools suffer from similar test ‘Replay’ problems such as the inability to find smaller-sized images. The repeatability of test executions was better for JAutomate in case of one of the two software under test (SUT) while it was comparable for the other. In terms of test development effort, for both tools, there were high correlations with number of steps in test suites, however the effort is reduced if test code is reused. The study has already provided benefits to the test engineers and managers in the company by increasing the know-how in the company w.r.t. VGT, and by identifying the challenges and their workarounds in using the tools. The industrial case study in this paper intends to add to the body of evidence in VGT and help other researchers and practitioners. [less ▲]

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See detailLes Trévires vus par le jésuite luxembourgeois Alexandre Wiltheim
Binsfeld, Andrea UL

in Hébert, Oriane; Pechoux, Ludivine (Eds.) Quand l’usage fait l’image. Les Gaulois, de la manipulation historique à l’archétype (in press)

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See detailMany Independent Objective (MIO) Algorithm for Test Suite Generation
Arcuri, Andrea UL

in Symposium on Search-Based Software Engineering (SSBSE) (in press)

Automatically generating test suites is intrinsically a multi- objective problem, as any of the testing targets (e.g, statements to exe- cute or mutants to kill) is an objective on its own. Test suite ... [more ▼]

Automatically generating test suites is intrinsically a multi- objective problem, as any of the testing targets (e.g, statements to exe- cute or mutants to kill) is an objective on its own. Test suite generation has peculiarities that are quite di erent from other more regular optimi- sation problems. For example, given an existing test suite, one can add more tests to cover the remaining objectives. One would like the smallest number of small tests to cover as many objectives as possible, but that is a secondary goal compared to covering those targets in the rst place. Furthermore, the amount of objectives in software testing can quickly become unmanageable, in the order of (tens/hundreds of) thousands, es- pecially for system testing of industrial size systems. Traditional multi- objective optimisation algorithms can already start to struggle with just four or ve objectives to optimize. To overcome these issues, di erent techniques have been proposed, like for example the Whole Test Suite (WTS) approach and the Many-Objective Sorting Algorithm (MOSA). However, those techniques might not scale well to very large numbers of objectives and limited search budgets (a typical case in system test- ing). In this paper, we propose a novel algorithm, called Many Indepen- dent Objective (MIO) algorithm. This algorithm is designed and tailored based on the speci c properties of test suite generation. An empirical study, on a set of arti cial and actual software, shows that the MIO al- gorithm can achieve higher coverage compared to WTS and MOSA, as it can better exploit the peculiarities of test suite generation. [less ▲]

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See detailAn Empirical Evaluation of Evolutionary Algorithms for Test Suite Generation
Campos, Jose; Ge, Yan; Fraser, Gordon et al

in Symposium on Search-Based Software Engineering (SSBSE) (in press)

Evolutionary algorithms have been shown to be effective at generating unit test suites optimised for code coverage. While many aspects of these algorithms have been evaluated in detail (e.g., test length ... [more ▼]

Evolutionary algorithms have been shown to be effective at generating unit test suites optimised for code coverage. While many aspects of these algorithms have been evaluated in detail (e.g., test length and different kinds of techniques aimed at improving performance, like seeding), the influence of the specific algorithms has to date seen less attention in the literature. As it is theoretically impossible to design an algorithm that is best on all possible problems, a common approach in software engineering problems is to first try a Genetic Algorithm, and only afterwards try to refine it or compare it with other algorithms to see if any of them is more suited for the addressed problem. This is particularly important in test generation, since recent work suggests that random search may in practice be equally effective, whereas the reformulation as a many-objective problem seems to be more effective. To shed light on the influence of the search algorithms, we empirically evaluate six different algorithms on a selection of non-trivial open source classes. Our study shows that the use of a test archive makes evolutionary algorithms clearly better than random testing, and it confirms that the many-objective search is the most effective. [less ▲]

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See detailTopologie culinaire au cinéma : le lieu commun du repas et ses déclinaison
Roelens, Nathalie UL

in Bibliothèque électronique Paris 8 (in press)

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See detailModelling Metrics for Transparency in Medical Systems
Pierina Brustolin Spagnuelo, Dayana UL; Bartolini, Cesare UL; Lenzini, Gabriele UL

in Proceedings of TrustBus 2017 (in press)

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See detailIntroducing automated GUI testing and observing its benefits: an industrial case study in the context of law-practice management software
Garousi, Vahid UL; Yıldırım, Erdem

in Proceedings of ACM/IEEE International Symposium on Empirical Software Engineering and Measurement (ESEM) (in press)

Motivated by a real-world industrial need in the context of a large IT solutions company based in Turkey, the authors and their colleagues developed and introduced automated test suites for GUI testing of ... [more ▼]

Motivated by a real-world industrial need in the context of a large IT solutions company based in Turkey, the authors and their colleagues developed and introduced automated test suites for GUI testing of two large-scale law-practice management software (comprising of 414 and 105 KLOC). We report in this paper our experience in developing and introducing a set of large automated test suites (more than 50 KLOC in total), using best practices in state-of-the art and –practice, and to report its observed benefits by conducting cost-benefit analysis in the specific industrial context. The project was conducted based on the principles of case-study and “action research” in which the real industrial needs drove the research. Among the best practices that we used are the followings: (1) the page-object test pattern, (2) modularity in test code, (3) creating test-specific libraries, and (4) using systematic guidelines to decide when and what (test cases) to automate. To assess the cost-benefit and Return On Investment (ROI) of test automation, we followed a hybrid measurement approach to assess both the quantitative and qualitative (intangible) benefits of test automation. The empirical findings showed that the automated GUI testing approach has indeed benefitted the test and QA team in the company under study and automation has been highly welcome by the test engineers. By serving as a success story and experience report in development and introduction of automated test suites in an industrial setting, this paper adds to the body of evidence in this area and it aims at sharing both technical (e.g., using automated test patterns) and process aspects (e.g., test process improvement) of our project with other practitioners and researchers with the hope of encouraging more industry-academia collaborations in test automation. [less ▲]

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See detailAere 'octroyed constitutions' of the 19th century to be considered as 'imposed constitutions'?
Gerkrath, Jörg UL

in Contiades, Xenophon (Ed.) ‘Imposed Constitutions: Aspects of Imposed Constitutionalism’ (in press)

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See detailHybrid Analog-Digital Transceiver Designs for Cognitive Radio Millimiter Wave Systems
Tsinos, Christos UL; Maleki, Sina UL; Chatzinotas, Symeon UL et al

in Hybrid Analog-Digital Transceiver Designs for Cognitive Radio Millimiter Wave Systems (in press)

Recent advances in Milimeter wave (mmWave) band mobile communications may provide solutions to the increasing traffic demand in modern wireless systems. Even though mmWave bands are scarcely occupied, the ... [more ▼]

Recent advances in Milimeter wave (mmWave) band mobile communications may provide solutions to the increasing traffic demand in modern wireless systems. Even though mmWave bands are scarcely occupied, the design of a prospect transceiver should guarantee the efficient coexistence with the incumbent services in these bands. To that end, in this paper, two underlay cognitive transceiver designs are proposed based on a hybrid Analog/Digital transceiver architecture that enables the mmWave spectrum access while controlling the interference to the incumbent users with low hardware complexity and power consumption. The first cognitive solution designs a codebook free cognitive hybrid pre-coder by maximizing the mutual information between its two ends subject to interference, power and hardware constraints related to the analog counterpart. The second solution is codebook based and exhibits less complexity than the first one at the cost of inferior spectral efficiency. A novel codebook free solution for the post-coder at the cognitive receiver part is further proposed, based on a hardware constrained Minimum Mean Square Error criterion. Simulations study the performance of both the proposed hybrid approaches and compare it to the one of a fully digital solution for typical wireless environments. [less ▲]

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See detailAutomatically Repairing Web Application Firewalls Based on Successful SQL Injection Attacks
Appelt, Dennis; Panichella, Annibale UL; Briand, Lionel UL

in The 28th IEEE International Symposium on Software Reliability Engineering (ISSRE) (in press)

Testing and fixing WAFs are two relevant and complementary challenges for security analysts. Automated testing helps to cost-effectively detect vulnerabilities in a WAF by generating effective test cases ... [more ▼]

Testing and fixing WAFs are two relevant and complementary challenges for security analysts. Automated testing helps to cost-effectively detect vulnerabilities in a WAF by generating effective test cases, i.e., attacks. Once vulnerabilities have been identified, the WAF needs to be fixed by augmenting its rule set to filter attacks without blocking legitimate requests. However, existing research suggests that rule sets are very difficult to understand and too complex to be manually fixed. In this paper, we formalise the problem of fixing vulnerable WAFs as a combinatorial optimisation problem. To solve it, we propose an automated approach that combines machine learning with multi-objective genetic algorithms. Given a set of legitimate requests and bypassing SQL injection attacks, our approach automatically infers regular expressions that, when added to the WAF's rule set, prevent many attacks while letting legitimate requests go through. Our empirical evaluation based on both open-source and proprietary WAFs shows that the generated filter rules are effective at blocking previously identified and successful SQL injection attacks (recall between 54.6% and 98.3%), while triggering in most cases no or few false positives (false positive rate between 0% and 2%). [less ▲]

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See detail« … Eripuit servus mihi vitam » - Représentations médiatiques de la violence et de la criminalité dans les provinces occidentales de l'Empire romain
Binsfeld, Andrea UL

in Amodio, Mara (Ed.) The imagery of violence in Roman society (I-VI cent.). Persistence, innovations and interrelations from the Roman to the Christian Empire (in press)

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See detailLe récit de voyage comme rupture de contrat
Roelens, Nathalie UL

in Acta Fabula : Revue des Parutions en Théorie Littéraire (in press)

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See detailComparisons of Heat Map and IFL Technique to Evaluate the Performance of Commercially Available Cloud Providers
Wagle, Shyam Sharan UL; Guzek, Mateusz UL; Bouvry, Pascal UL et al

in Comparisons of Heat Map and IFL Technique to Evaluate the Performance of Commercially Available Cloud Providers (in press)

Cloud service providers (CSPs) offer different Ser- vice Level Agreements (SLAs) to the cloud users. Cloud Service Brokers (CSBs) provide multiple sets of alternatives to the cloud users according to ... [more ▼]

Cloud service providers (CSPs) offer different Ser- vice Level Agreements (SLAs) to the cloud users. Cloud Service Brokers (CSBs) provide multiple sets of alternatives to the cloud users according to users requirements. Generally, a CSB considers the service commitments of CSPs rather than the actual quality of CSPs services. To overcome this issue, the broker should verify the service performances while recommending cloud services to the cloud users, using all available data. In this paper, we compare our two approaches to do so: a min-max-min decomposition based on Intuitionistic Fuzzy Logic (IFL) and a Performance Heat Map technique, to evaluate the performance of commercially available cloud providers. While the IFL technique provides simple, total order of the evaluated CSPs, Performance Heat Map provides transparent and explanatory, yet consistent evaluation of service performance of commercially available CSPs. The identified drawbacks of the IFL technique are: 1) It does not return the accurate performance evaluation over multiple decision alternatives due to highly influenced by critical feedback of the evaluators; 2) Overall ranking of the CSPs is not as expected according to the performance measurement. As a result, we recommend to use performance Heat Map for this problem. [less ▲]

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See detailMulti-objective regression test selection in practice: an empirical study in the defense software industry
Özkan, Ramazan; Garousi, Vahid UL; Betin-Can, Aysu

in Proceedings of ACM/IEEE International Symposium on Empirical Software Engineering and Measurement (ESEM) (in press)

Executing an entire regression test suite after every code change is often costly in large software projects. To address this challenge, various regression test selection techniques have been proposed in ... [more ▼]

Executing an entire regression test suite after every code change is often costly in large software projects. To address this challenge, various regression test selection techniques have been proposed in the literature. One of those approaches is the Multi-Objective Regression Test Optimization (MORTO) approach, which is applied when there are multiple objectives during regression testing (e.g., minimizing the number of test cases and maximizing test coverage). This paper reports an action research type of study which was conducted to improve regression test-selection practices of a safety-critical industrial software in the defence domain based on the MORTO approach. The problem is formulated and solved by converting the multi-objective genetic-algorithm (GA) problem into a custom-built scalarized single-objective GA. The empirical results demonstrate that this approach yields a more efficient test suite (in terms of testing cost and benefits) compared to the old (manual) test-selection approach and another approach from the literature, i.e., the selective requirement coverage-based approach. Based on the context and need of the company, we developed the GA-based solution on a set of five cost objectives and four benefit objectives for regression testing while providing full coverage of the affected (changed) requirements. Since our proposed approach has been beneficial in the industrial context, it is currently in active use in the company. [less ▲]

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See detailLe dialogue entre les juges en matière de protection des droits de l'homme
Pelin Raducu, Ioana UL

in Menetrey, Séverine; Hess, Burkhard (Eds.) Les dialogues des juges en Europe (in press)

Dans cet article, nous allons mettre en exergue quelques aspects des arrêts récents provenant de la Cour de justice de l’UE (Akerberg Frasson, Melloni, Kamberaj)qui démontrent l’émergence d’un standard ... [more ▼]

Dans cet article, nous allons mettre en exergue quelques aspects des arrêts récents provenant de la Cour de justice de l’UE (Akerberg Frasson, Melloni, Kamberaj)qui démontrent l’émergence d’un standard propre de l’UE en matière des droits de l’homme. Cette tendance de la C.J.U.E. contredira le prescrit normatif découlant du « dialogue des juges » d’interprétation conforme à la jurisprudence de la C.E.D.H. avant que l’adhésion de l’UE à la Convention E.D.H. ne soit formellement acquise. [less ▲]

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See detailRESTful API Automated Test Case Generation
Arcuri, Andrea UL

in IEEE International Conference on Software Quality, Reliability & Security (QRS) (in press)

Nowadays, web services play a major role in the development of enterprise applications. Many such applications are now developed using a service-oriented architecture (SOA), where microservices is one of ... [more ▼]

Nowadays, web services play a major role in the development of enterprise applications. Many such applications are now developed using a service-oriented architecture (SOA), where microservices is one of its most popular kind. A RESTful web service will provide data via an API over the network using HTTP, possibly interacting with databases and other web services. Testing a RESTful API poses challenges, as inputs/outputs are sequences of HTTP requests/responses to a remote server. Many approaches in the literature do black-box testing, as the tested API is a remote service whose code is not available. In this paper, we consider testing from the point of view of the developers, which do have full access to the code that they are writing. Therefore, we propose a fully automated white-box testing approach, where test cases are automatically generated using an evolutionary algorithm. Tests are rewarded based on code coverage and fault finding metrics. We implemented our technique in a tool called EVOMASTER, which is open-source. Experiments on two open-source, yet non-trivial RESTful services and an industrial one, do show that our novel technique did automatically find 38 real bugs in those applications. However, obtained code coverage is lower than the one achieved by the manually written test suites already existing in those services. Research directions on how to further improve such approach are therefore discussed. [less ▲]

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See detailL’exposition d’objets ou de collections de « marque » : cobranding, réécriture, réénonciation
Schall, Céline UL

in Laval, Sylvie (Ed.) Marques muséales : un espace public revisité ? (in press)

Le cobranding est une pratique habituelle du secteur marchand. Mais lorsque deux musées réalisent ensemble une exposition, peut-on parler de cobranding muséal ? Quelles en seraient les spécificités  ... [more ▼]

Le cobranding est une pratique habituelle du secteur marchand. Mais lorsque deux musées réalisent ensemble une exposition, peut-on parler de cobranding muséal ? Quelles en seraient les spécificités ? Quels effets peut avoir cette démarche sur la communication ou sur l’exposition ? Notamment, le musée d’accueil s’approprie-t-il simplement l’imaginaire et les valeurs de la marque invitée par un phénomène de « transfert » ? Pour répondre à ces questions, nous étudions trois expositions qui reprennent des objets ou collections de musées dont la marque est internationalement reconnue. L’analyse sémiotique des images de marque du musée d’accueil et du musée invité ainsi que l’analyse sémiopragmatique des expositions montrent l’impact de la présence d’une grande marque internationale sur l’exposition et réciproquement, l’impact de l’exposition sur l’image de marque du musée d’accueil. Plus qu’un simple cobranding, c’est une réécriture impliquant une réénonciation du discours et des valeurs portés par les marques qui est proposée à travers ces expositions. Le processus aboutit à la création de nouveaux espaces symboliques et d’expositions réflexives, avec plusieurs niveaux de lecture. [less ▲]

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See detailLe quotidien d’un poilu de la première guerre mondiale sur Facebook : nouvelle forme de médiation, nouvelle expérience ?
Schall, Céline UL; Vilatte, Jean-Christophe

in Les mondes de la médiation culturelle (in press)

« En 2013, le Musée de la Grande Guerre du Pays de Meaux et l’agence de communication DDB ont élaboré une page Facebook d’un genre nouveau. Facebook 1914, le quotidien de la première guerre offre une ... [more ▼]

« En 2013, le Musée de la Grande Guerre du Pays de Meaux et l’agence de communication DDB ont élaboré une page Facebook d’un genre nouveau. Facebook 1914, le quotidien de la première guerre offre une forme de médiation a priori inédite pour un musée français. Elle présente l’histoire d’un personnage de fiction, Léon Vivien, qui raconte son quotidien lors de la première guerre mondiale, sur Facebook, comme si ce réseau social avait existé à cette époque. Cette contribution met en évidence certains des effets de sens de la page par une analyse sémiotique du dispositif et une analyse thématique de ses contenus. Nous questionnons ensuite cette « nouvelle » forme de médiation qui se dit « participante » et qui, en réalité, reste assez classique dans son contenu et sous-exploite le potentiel de Facebook. » [less ▲]

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See detailHistorical outline and chromatic properties of purpura rubra Tarentina and its potential identification with purple dye extracted from Bolinus brandaris
Meiers, Fabienne UL

in Enegren, Hedvig; Meo, Francesco (Eds.) Treasures from the Sea : Sea-Silk and Shell purple dye in antiquity. Proceedings from the International workshop, 26.-28.05. (in press)

This paper presents a historical overview of the importance of the red dye found in spiny dye-murices (Bolinus brandaris) and its production in Taranto, one of the most industrious Greek colonies founded ... [more ▼]

This paper presents a historical overview of the importance of the red dye found in spiny dye-murices (Bolinus brandaris) and its production in Taranto, one of the most industrious Greek colonies founded in southern Italy in the 8th century BC and renowned for its luxury products. Written evidence as well as numismatic and archaeological sources dating from the 5th century BC to the 5th century AD have been analysed in this context to identify purpura rubra Tarentina. In addition, the results of a series of dye experiments with hypobranchial glands from the same species are treated in order to detect chromatic properties and potential manufacturing processes for Tarentine Red. The methods for vatting the dye glands are discussed in relation to historical validity and chromatic outcome. To conclude, comparisons are drawn between the colour characteristics of Bolinus brandaris and Hexaplex trunculus (banded dye-murex), and the possibility of mixing both dyes is taken into consideration. The synthesis of historical and experimental approach finally shows that purpura rubra Tarentina can potentially be identified with purple dye extracted from Bolinus brandaris. [less ▲]

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See detailLes bourgeois de Bohême et l’impossible légitimation ? La conjuration de Prague et de Kutná Hora de février 1309
Vomacka, Eloïse UL

in Contester au Moyen Âge : de la désobéissance à la révolte XLIXe congrès de la SHMESP (2018)

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See detailEstimating Urban Road Traffic States Using Mobile Network Signaling Data
Derrmann, Thierry UL; Frank, Raphaël UL; Viti, Francesco UL et al

in Derrmann, Thierry; Frank, Raphaël; Viti, Francesco (Eds.) et al Estimating Urban Road Traffic States Using Mobile Network Signaling Data (2017, October)

It is intuitive that there is a causal relationship between human mobility and signaling events in mobile phone networks. Among these events, not only the initiation of calls and data sessions can be used ... [more ▼]

It is intuitive that there is a causal relationship between human mobility and signaling events in mobile phone networks. Among these events, not only the initiation of calls and data sessions can be used in analyses, but also handovers between different locations that reflect mobility. In this work, we investigate if handovers can be used as a proxy metric for flows in the underlying road network, especially in urban environments. More precisely, we show that characteristic profiles of handovers within and between clusters of mobile network cells exist. We base these profiles on models from road traffic flow theory, and show that they can be used for traffic state estimation using floating-car data as ground truth. The presented model can be beneficial in areas with good mobile network coverage but low road traffic counting infrastructure, e.g. in developing countries, but also serve as an additional predictor for existing traffic state monitoring systems. [less ▲]

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See detailMechanical Model to Predict the Resistance of the Shear Connection in Composite Beams with Deep Steel Decking
Odenbreit, Christoph UL; Nellinger, Sebastian UL

in Eurosteel 2017 (2017, September 13)

The resistance of a typical shear connection with headed shear studs in a composite beam is analysed in the normal case in accordance with EN 1994-1-1. The reducing effect of a trapezoidal metal decking ... [more ▼]

The resistance of a typical shear connection with headed shear studs in a composite beam is analysed in the normal case in accordance with EN 1994-1-1. The reducing effect of a trapezoidal metal decking onto the ultimate load bearing capacity is considered with empirically derived reduction factors and equations, which have been developed in the last century between the late 70th and the early 80th. The RFCS research project “DISCCO” investigated the shear stud resistance with novel types of steel decking. In many cases, the shear resistance, which was predicted by EN 1994-1-1 was not reached in tests. In the respective experiments with composite beams and deep decking, a concrete cone failure mode was identified and not a pure shear failure of the stud. This failure mode acted in combination with the load bearing capacity of the shear stud, which formed one or two plastic hinges in the shaft - depending on the available geometry. Based on these observations, new equations have been developed to predict the shear connection’s resistance with more accurcy. The yield hinge mechanism of the shear stud, which was developed by Lungershausen, was extended by the above mentioned load bearing component ‘concrete cone’. The formulae consider the geometry of the stud and the steel decking, the material strength of the stud and of the concrete material. The statistical evaluation of the developed equations shows a good accordance with test results. [less ▲]

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See detailLIPS vs MOSA: a Replicated Em- pirical Study on Automated Test Case Generation
Panichella, Annibale UL; Kifetew, Fitsum; Tonella, Paolo

in International Symposium on Search Based Software Engineering (SSBSE) 2017 (2017, September 09)

Replication is a fundamental pillar in the construction of scientific knowledge. Test data generation for procedural programs can be tackled using a single-target or a many-objective approach. The ... [more ▼]

Replication is a fundamental pillar in the construction of scientific knowledge. Test data generation for procedural programs can be tackled using a single-target or a many-objective approach. The proponents of LIPS, a novel single-target test generator, conducted a preliminary empirical study to compare their approach with MOSA, an alternative many-objective test generator. However, their empirical investigation suffers from several external and internal validity threats, does not consider complex programs with many branches and does not include any qualitative analysis to interpret the results. In this paper, we report the results of a replication of the original study designed to address its major limitations and threats to validity. The new findings draw a completely different picture on the pros and cons of single-target vs many-objective approaches to test case generation. [less ▲]

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See detailMultiscale Modelling of Damage and Fracture in Discrete Materials Using a Variational Quasicontinuum Method
Rokos, Ondrej; Peerlings, Ron; Beex, Lars UL et al

Scientific Conference (2017, September 05)

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See detailA Model-Driven Approach to Trace Checking of Pattern-based Temporal Properties
Dou, Wei; Bianculli, Domenico UL; Briand, Lionel UL

in Proceedings of the ACM/IEEE 20th International Conference on Model Driven Engineering Languages and Systems (MODELS 2017 ) (2017, September)

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See detailDie Trainierbarkeit von komplexem Problemlösen im Rahmen eines Trainings für Experimentieren.
Stebner, Ferdinand; Kunze, Thiemo UL; Kemper, Christoph UL et al

Scientific Conference (2017, September)

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See detailIs Big Data Sufficient for a Reliable Detection of Non-Technical Losses?
Glauner, Patrick UL; Migliosi, Angelo UL; Meira, Jorge Augusto UL et al

in Proceedings of the 19th International Conference on Intelligent System Applications to Power Systems (ISAP 2017) (2017, September)

Non-technical losses (NTL) occur during the distribution of electricity in power grids and include, but are not limited to, electricity theft and faulty meters. In emerging countries, they may range up to ... [more ▼]

Non-technical losses (NTL) occur during the distribution of electricity in power grids and include, but are not limited to, electricity theft and faulty meters. In emerging countries, they may range up to 40% of the total electricity distributed. In order to detect NTLs, machine learning methods are used that learn irregular consumption patterns from customer data and inspection results. The Big Data paradigm followed in modern machine learning reflects the desire of deriving better conclusions from simply analyzing more data, without the necessity of looking at theory and models. However, the sample of inspected customers may be biased, i.e. it does not represent the population of all customers. As a consequence, machine learning models trained on these inspection results are biased as well and therefore lead to unreliable predictions of whether customers cause NTL or not. In machine learning, this issue is called covariate shift and has not been addressed in the literature on NTL detection yet. In this work, we present a novel framework for quantifying and visualizing covariate shift. We apply it to a commercial data set from Brazil that consists of 3.6M customers and 820K inspection results. We show that some features have a stronger covariate shift than others, making predictions less reliable. In particular, previous inspections were focused on certain neighborhoods or customer classes and that they were not sufficiently spread among the population of customers. This framework is about to be deployed in a commercial product for NTL detection. [less ▲]

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See detailJoanAudit: A Tool for Auditing Common Injection Vulnerabilities
Thome, Julian UL; Shar, Lwin Khin UL; Bianculli, Domenico UL et al

in 11th Joint Meeting of the European Software Engineering Conference and the ACM SIGSOFT Symposium on the Foundations of Software Engineering (2017, September)

JoanAudit is a static analysis tool to assist security auditors in auditing Web applications and Web services for common injection vulnerabilities during software development. It automatically identifies ... [more ▼]

JoanAudit is a static analysis tool to assist security auditors in auditing Web applications and Web services for common injection vulnerabilities during software development. It automatically identifies parts of the program code that are relevant for security and generates an HTML report to guide security auditors audit the source code in a scalable way. JoanAudit is configured with various security-sensitive input sources and sinks relevant to injection vulnerabilities and standard sanitization procedures that prevent these vulnerabilities. It can also automatically fix some cases of vulnerabilities in source code — cases where inputs are directly used in sinks without any form of sanitization — by using standard sanitization procedures. Our evaluation shows that by using JoanAudit, security auditors are required to inspect only 1% of the total code for auditing common injection vulnerabilities. The screen-cast demo is available at https://github.com/julianthome/joanaudit. [less ▲]

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See detailKomplexes Problemlösen und Intelligenz
Greiff, Samuel UL

Scientific Conference (2017, September)

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See detailMining AndroZoo: A Retrospect
Li, Li UL

in The International Conference on Software Maintenance and Evolution (ICSME) (2017, September)

This paper presents a retrospect of an Android app collection named AndroZoo and some research works conducted on top of the collection. AndroZoo is a growing collection of Android apps from various ... [more ▼]

This paper presents a retrospect of an Android app collection named AndroZoo and some research works conducted on top of the collection. AndroZoo is a growing collection of Android apps from various markets including the official Google Play. At the moment, over five million Android apps have been collected. Based on AndroZoo, we have explored several directions that mine Android apps for resolving various challenges. In this work, we summarize those resolved mining challenges in three research dimensions, including code analysis, app evolution analysis, malware analysis, and present in each dimension several case studies that experimentally demonstrate the usefulness of AndroZoo. [less ▲]

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See detailLegal Markup Generation in the Large: An Experience Report
Sannier, Nicolas UL; Adedjouma, Morayo UL; Sabetzadeh, Mehrdad UL et al

in the 25th International Requirements Engineering Conference (RE'17), Lisbon, 4-8 September 2017 (2017, September)

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See detailThe relevance of verbal and visuo-spatial abilities for verbal number skills – what matters in 5 to 6 year olds?
Cornu, Véronique UL; Schiltz, Christine UL; Martin, Romain UL et al

Poster (2017, September)

The acquisition of verbal number skills, as defined by the meaningful use of number words, marks a milestone in numerical development. In the present study, we were particularly interested in the question ... [more ▼]

The acquisition of verbal number skills, as defined by the meaningful use of number words, marks a milestone in numerical development. In the present study, we were particularly interested in the question, whether verbal number skills are primarily verbal in nature, or if they call upon visuo-spatial processes, reflecting a spatial grounding of verbal number skills. 141 five- to six-year old children were tested on a range of verbal (i.e. vocabulary, phonological awareness and verbal working memory) and visuo-spatial abilities (i.e. spatial perception, visuo-motor integration and visuo-spatial working memory). We were particularly interested in the predictive role of these abilities for children’s verbal number skills (as measured by different counting and number naming tasks). In a latent regression model, basic visuo-spatial abilities, measured by spatial perception and visuo-motor integration, emerge as the most important predictor of verbal number skills. This gives raise to the assumption, that verbal number skills are, despite their verbal nature, spatially grounded in young children. [less ▲]

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See detailA Deep Learning Approach for Optimizing Content Delivering in Cache-Enabled HetNet
Lei, Lei UL; You, Lei; Dai, Gaoyang et al

in IEEE International Symposium on Wireless Communication Systems (ISWCS), Bologna, Aug. 2017 (2017, August 31)

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See detailCoverage optimization with connectivity preservation for UAV swarms applying chaotic dynamics
Rosalie, Martin UL; Brust, Matthias UL; Danoy, Grégoire UL et al

in IEEE International Conference on Autonomic Computing (ICAC), Columbus 17-21 July 2017 (2017, August 11)

Cooperative usage of multiple UAVs as a swarm can deliver high-quality surveillance performance. However, the communication capabilities within the UAV swarm must be maintained for local data propagation ... [more ▼]

Cooperative usage of multiple UAVs as a swarm can deliver high-quality surveillance performance. However, the communication capabilities within the UAV swarm must be maintained for local data propagation to swarm members in favor of achieving an efficient global behavior. In this paper, we address the problem of optimizing two adversary criteria for such a UAV swarm: (a) maximizing the area coverage, while (b) preserving network connectivity. Our approach, called CACOC², solves the problem with a novel chaotic ant colony optimization approach, which combines an Ant Colony Optimization approach (ACO) with a chaotic dynamical system. CACOC² employs swarming behavior to obtain UAV clustering that result in maximized area coverage and preserved network connectivity. We show by extensive simulations how the size of the UAV swarm influences the coverage and connectivity. A metrics comparison chart shows the correlation of coverage and connectivity metrics. [less ▲]

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See detailDignity as Discursive Enactment of Tradition: A Narrative Approach on Tradition in Family Business
Adiguna, Rocky UL

Scientific Conference (2017, August 06)

Our current understanding of tradition in organizations remain very limited. The lack of studies that take tradition as the main focus have made this concept overlooked as an important organizational ... [more ▼]

Our current understanding of tradition in organizations remain very limited. The lack of studies that take tradition as the main focus have made this concept overlooked as an important organizational feature. In this paper, I set out to address this issue by exploring how tradition is (re)produced and (re)interpreted in a century-old family-owned hotel. By adopting a narrative approach as an interpretive lens, I found that the reproduction and reinterpretation of tradition is discursively mediated through the notion of dignity. In particular, this paper argues for three forms of 'doing' dignity: first, dignity-by-category that is enacted through the discursive use of category making; second, dignity-by-sanctity that is enacted through sanctifying particular relations; and third, dignity-by-authority that is enacted through the exercise of authority to compel others to acknowledge one's dignity. To extend it further, the possibility of conceptual relations between tradition, dignity, and narrative identity is discussed. Drawing from the broader fields of social sciences, this study contributes to the scarce literature on tradition theory and dignity in organizations. [less ▲]

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See detailPanel participant
Greiff, Samuel UL

Scientific Conference (2017, August)

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See detailRandom Phase Center Motion Technique for Enhanced Angle-Doppler Discrimination Using MIMO Radars
Hammes, Christian UL; Shankar, Bhavani UL; Nijsure, Yogesh UL et al

Scientific Conference (2017, August)

A random Phase Center Motion (PCM) technique is presented in this paper, based on Frequency Modulated Continuous Wave (FMCW) radar, in order to suppress the angle- Doppler coupling in Time Division ... [more ▼]

A random Phase Center Motion (PCM) technique is presented in this paper, based on Frequency Modulated Continuous Wave (FMCW) radar, in order to suppress the angle- Doppler coupling in Time Division Multiplex (TDM) Multiple- Input-Multiple-Output (MIMO) radar when employing sparse array structures. The presented approach exploits an apparently moving transmit platform or PCM due to spatio-temporal transmit array modulation. In particular, the work considers a framework utilizing a random PCM trajectory. The statistical characterization of the random PCM trajectory is devised, such that the PCM and the target motion coupling is minimal, while the angular resolution is increased by enabling the virtual MIMO concept. In more details, this paper discusses sidelobe suppression approaches within the angle-Doppler Ambiguity Function (AF) by introducing a phase center probability density function within the array. This allows for enhanced discrimination of multiple targets. Simulation results demonstrate the suppression angle- Doppler coupling by more than 30 dB, even though spatiotemporal transmit array modulation is done across chirps which leads usually to strong angle-Doppler coupling. [less ▲]

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See detailAn engineering approach to mapping meanings in products and services
Waltersdorfer, Gregor UL; Gericke, Kilian UL; Desmet, Pieter M. A. et al

Scientific Conference (2017, August)

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See detailThe role of international organisations in the New Math reform process
Nadimi Amiri, Shaghayegh UL

Scientific Conference (2017, August)

This paper studies a particular school reform that travelled over countries and continents. The target reform of this paper is the New Math reform, which started in the United States and travelled through ... [more ▼]

This paper studies a particular school reform that travelled over countries and continents. The target reform of this paper is the New Math reform, which started in the United States and travelled through many European countries. This article is part of my PhD project. I previously presented some of the results in different conferences, for instance: (Nadimi, 2015a, 2015b, 2016). The present paper studies the role of the international institutions in the adaptation of the reform in Luxembourg In 1958, the School Mathematics Study Group (SMSG) in the United States started a series of mathematics reform under the title “the New Math reform”. The aim of this reform plan was to promote the “problem solving” abilities in students (Phillips, 2014, pp. 16- 59). Many of mathematicians and math educators who became a member of the SMSG, had already started working on a new system of math education at the University of Chicago since 1955. However, the launch of Sputnik satellite by the USSR in 1957 gave the opportunity to trigger the New Math reform. The origin of the New Math reform was the ‘modern mathematics’ of the French Bourbaki group. A group of French mathematicians, since 1935, under the pseudonym Nicolas Bourbaki founded the “modern mathematics” by publishing the series of Elements of Mathematics (Bourbaki's_homepage). The reform came back to its land of origin through a conference organised by OEEC (Organisation for European Economic Co-operation) in the Royaumont abbey in Paris to foster the reform movement in Europe (OECD, 1961). The official title of the conference was “New thinking in mathematics education”, but it is known as the “Royaumont seminar”. OECD (the Organisation succeeding the OEEC) published the proceeding of the conference and organised other following conferences. The fact that OEEC/OECD hosts these conferences shows the politico-economic aspect of this reform. (Tröhler, 2015, p. 6) indicates that organisations like OEEC were created to link the national and the international, to create a global sphere, and to form an institutional or organisational channel to transfer desired ideas, policies, and curricula. The practical implementations of the New Math reform, in Europe, were discussed in two international organisations: ICMI (International Commission on Mathematical Instruction), founded in 1908, and CIEAEM (Commission Internationale pour l’Étude et l’Améloration de l’Enseignement des Mathématiques), established in 1950 (Vanpaemel, 2012). Furthermore, there were also local institutions, such as Centre Belge de Pédagogie de la Mathématique (CBPM). This centre had a close collaboration with Luxembourgian teachers and school stakeholders. This paper reviews the process of the New Math reform in Luxembourg by focusing on the interactions between the international institutions and the local school system. By telling the story of Luxembourg, the paper reveals a part of history related to the acts and efforts of the mentioned international organisations in the dissemination of the New Math reform idea in Europe. It shows how the national and international interactions could help the advancement of the reform and where the collaboration met challenges. The central question that shapes the paper is that up to what point the international cooperation of Luxembourgian stakeholders could be influential at the national level. This can be an example of how the acts and efforts of international organisations interact with the local interested parties in the development of an educational idea. [less ▲]

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See detailWhat do we need to say about a design method?
Gericke, Kilian UL; Eckert, Claudia; Stacey, Martin

in Proceedings of the 21st International Conference on Engineering Design (2017, August)

Method development is one of the raisons d’etre of engineering design research and method uptake by industry is perceived as an important success criterion. This paper argues that one of the problems with ... [more ▼]

Method development is one of the raisons d’etre of engineering design research and method uptake by industry is perceived as an important success criterion. This paper argues that one of the problems with methods is the lack of clarity about what is actually proposed to industry and the academic community when a new method is put forward, in terms of how detailed, strict, precise and rigorous the method is and what it can deliver. This paper puts the concept of method in the context of related concepts and proposes a multi-level model of the elements of a method to argue that a contribution on each of these levels can be of value and that the introduction of methods can fail on each of these levels. Implications thereof for industry and academia are discussed, concluding that a clear description of methods and their intended use is important for enabling proper validation of each of the method’s elements and for communicating methods to academia and industry. [less ▲]

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See detailCollaborative problem solving behavior. A deep dive into log files
Schweitzer, Nick UL; Herborn, Katharina UL; Mustafic, Maida UL et al

Scientific Conference (2017, August)

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See detailDiscussant
Greiff, Samuel UL

Scientific Conference (2017, August)

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See detailAn Extensible and Lightweight Modular Ontology for Programming Education
Grevisse, Christian UL; Botev, Jean UL; Rothkugel, Steffen UL

in Advances in Computing - 12th Colombian Conference, CCC 2017, Cali, Colombia, September 19-22, 2017, Proceedings (2017, August)

Semantic web technologies such as ontologies can foster the reusability of learning material by introducing common sets of concepts for annotation purposes. However, suggesting learning material from an ... [more ▼]

Semantic web technologies such as ontologies can foster the reusability of learning material by introducing common sets of concepts for annotation purposes. However, suggesting learning material from an open, heterogeneous corpus is a nontrivial problem. In this paper, we propose an extensible and lightweight modular ontology for programming education. Its main purpose is to integrate annotated learning material related to programming into an IDE such as Eclipse. Our ontology is based on a modular architecture, which is extensible with respect to different programming languages. Aligning language-specific concepts with user-specific tags allows us to suggest learning resources for code elements in a fine-grained and cross-curricular way. Our concrete implementation establishes relations between learning aspects in Java or C code and annotated resources such as articles on online question-and-answer sites. [less ▲]

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See detailBelief Change in a Preferential Non-Monotonic Framework
Casini, Giovanni UL; Meyer, Thomas

in Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence (2017, August)

Belief change and non-monotonic reasoning are usually viewed as two sides of the same coin, with results showing that one can formally be defined in terms of the other. In this paper we show that we can ... [more ▼]

Belief change and non-monotonic reasoning are usually viewed as two sides of the same coin, with results showing that one can formally be defined in terms of the other. In this paper we show that we can also integrate the two formalisms by studying belief change within a (preferential) non-monotonic framework. This integration relies heavily on the identification of the monotonic core of a non-monotonic framework. We consider belief change operators in a non-monotonic propositional setting with a view towards preserving consistency. These results can also be applied to the preservation of coherence—an important notion within the field of logic-based ontologies. We show that the standard AGM approach to belief change can be adapted to a preferential non-monotonic framework, with the definition of expansion, contraction, and revision operators, and corresponding representation results. Surprisingly, preferential AGM belief change, as defined here, can be obtained in terms of classical AGM belief change. [less ▲]

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See detailDevelopment of a new push test for Eurocode 4
Hicks, Stephen; Ciutina, Adrian; Odenbreit, Christoph UL

in 8th International Conference on Composite Construction in Steel and Concrete (2017, July 30)

The standard push test specimen in the current version of Eurocode 4 does not provide any information on what modifications should be made when profiled steel sheeting is introduced. Whilst the lack of ... [more ▼]

The standard push test specimen in the current version of Eurocode 4 does not provide any information on what modifications should be made when profiled steel sheeting is introduced. Whilst the lack of information was intended to encourage innovation, this has sometimes lead to test results implying that stud connectors possess a lower resistance and ductility than assumed in current Standards. From full-scale beam and companion push tests in Europe, it has been shown that modifying the push test through the introduction of a normal force to the face of the test slabs provides comparable load-slip performance to that encountered within a beam. Within the work programme for developing the second generation of Eurocodes, this paper presents part of the background to Sub-task 1 of SC4.T3, whose aim is to develop an improved push test for Eurocode 4 when stud connectors are welded within profiled steel sheeting. [less ▲]

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See detailArea exploration with a swarm of UAVs combining deterministic Chaotic Ant Colony Mobility with position MPC
Rosalie, Martin UL; Dentler, Jan Eric UL; Danoy, Grégoire UL et al

in 2017 International Conference on Unmanned Aircraft Systems (ICUAS) (2017, July 27)

The recent advances in Unmanned Aerial Vehicles (UAVs) technology permit to develop new usages for them. One of the current challenges is to operate UAVs as an autonomous swarm. In this domain we already ... [more ▼]

The recent advances in Unmanned Aerial Vehicles (UAVs) technology permit to develop new usages for them. One of the current challenges is to operate UAVs as an autonomous swarm. In this domain we already proposed a new mobility model using Ant Colony Algorithms combined with chaotic dynamics (CACOC) to enhance the coverage of an area by a swarm of UAVs. In this paper we propose to consider this mobility model as waypoints for real UAVs. A control model of the UAVs is deployed to test the efficiency of the coverage of an area by the swarm. We have tested our approach in a realistic robotics simulator (V-Rep) which is connected with ROS. We compare the performance in terms of coverage using several metrics to ensure that this mobility model is efficient for real UAVs. [less ▲]

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See detaileXtended Variational Quasicontinuum Methodology for Modelling of Crack Propagation in Discrete Lattice Systems
Rokos, Ondrej; Peerlings, Ron; Zeman, Jan et al

Scientific Conference (2017, July 17)

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See detailChanging (multi-)cultural contexts through the lense of the receiving society
Murdock, Elke UL; Albert, Isabelle UL; Ferring, Dieter UL

in 9th European IACCP Conference - Program and the book of abstracts (2017, July 17)

Using the natural laboratory of Luxembourg with a foreign population of 47% as case study example, we outline the diversification of diversity. The immigrant population is increasingly heterogeneous in ... [more ▼]

Using the natural laboratory of Luxembourg with a foreign population of 47% as case study example, we outline the diversification of diversity. The immigrant population is increasingly heterogeneous in terms of countries of origin, length of stay/ generation status, economic participation and acculturation choices. Who is a Luxembourger is increasingly difficult to define and minority or majority becomes ever more fluid. Empirical findings concerning the attitude of the receiving society towards multiculturalism will be presented including implications for national identification. We aim to shed light on inter-individual differences in terms of views on immigration among the receiving society, also taking into consideration regional demographic differences. We draw on two different samples, one from the center of Luxembourg (N = 507), where the native population is in the minority and a more regionally diversified sample (N = 238). Similarities and differences will be highlighted and implications discussed. [less ▲]

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See detailAn equation-free multiscale method: a result of extending the quasicontinuum method to irregular structures
Beex, Lars UL; Kerfriden, Pierre

Scientific Conference (2017, July 16)

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See detailA Global Vertical Land Movement Data Set from a Combination of Global Navigation Satellite System Solutions
Hunegnaw, Addisu UL; Teferle, Felix Norman UL; Abraha, Kibrom Ebuy UL et al

Poster (2017, July 13)

Coastal sea-level measurements by tide gauges provide the longest instrumental records of sea-levels with some stretching from the 19th century to present. The derived mean sea-level (MSL) records provide ... [more ▼]

Coastal sea-level measurements by tide gauges provide the longest instrumental records of sea-levels with some stretching from the 19th century to present. The derived mean sea-level (MSL) records provide sea-level relative to a nearby tide gauge benchmark (TGBM), which allows for the continuation of this record in time after, for example, equipment modifications. Any changes in the benchmark levels induced by vertical land movements (VLM) affect the MSL records and hence the computed sea-levels. In the past, MSL records affected by VLM were often excluded from further analyses or the VLM were modelled using numerical models of the glacial isostatic adjustment (GIA) process. Over the last two decades Global Navigation Satellite System (GNSS), in particular Global Positioning System (GPS), measurements at or close to tide gauges and the development of the associated processing strategies, have made it possible to obtain estimates of VLM in a geocentric reference system, such as the International Terrestrial Reference Frame release 2008 (ITRF2008) that approach the required accuracy for sea-level studies. Furthermore, the GPS-derived VLM estimates have been shown to improve estimates of sea-level change compared to those using the aforementioned GIA models as these models cannot predict local subsidence or uplift. The International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group has recently re-processed the global GNSS data set from its archive (1000+ stations for 1995-2014) to provide VLM estimates tuned for the sea-level community. To achieve this, five TIGA Analysis Centers (TAC) contributed their reprocessed global GPS network solutions to the WG, all employing the latest bias models and processing strategies in accordance with the second re-processing compaign (repro2) of the IGS. These individual solutions were then combined by the TIGA Combination Center (TCC) to produce, for the first time, a TIGA combined solution (Release 0.99). This combined solution allows an evaluation of each individual TAC solution while also providing a means to gauge the quality and reliability of the combined solution, which is generally regarded as superior to the individual TAC solutions. Using time series analysis methods, estimates of VLM can then be derived from the daily position estimates, which are sub-sequentially employed to investigate coastal sea-levels. In this study, we show results from the evaluation of the relevant solutions, provide an evaluation of the TIGA VLM estimates and give examples of their impact on sea-level estimates for selected tide gauges from around the world. The TAC and TIGA combined solutions, as well as the derived VLM data sets are available from the IGS TIGA WG and will be accessible through SONEL (www.sonel.org) in the near future. [less ▲]

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See detailError-controlled computational fracture mechanics
Bordas, Stéphane UL

Scientific Conference (2017, July 12)

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See detailRisk-averse Stochastic Nonlinear Model Predictive Control for Real-time Safety-critical Systems
Sajadi Alamdari, Seyed Amin UL; Voos, Holger UL; Darouach, Mohamed

in The 20th World Congress of the International Federation of Automatic Control, IFAC 2017 World Congress, Toulouse, France, 9-14 July 2017 (2017, July 11)

Stochastic nonlinear model predictive control has been developed to systematically find an optimal decision with the aim of performance improvement in dynamical systems that involve uncertainties. However ... [more ▼]

Stochastic nonlinear model predictive control has been developed to systematically find an optimal decision with the aim of performance improvement in dynamical systems that involve uncertainties. However, most of the current methods are risk-neutral for safety-critical systems and depend on computationally expensive algorithms. This paper investigates on the risk-averse optimal stochastic nonlinear control subject to real-time safety-critical systems. In order to achieve a computationally tractable design and integrate knowledge about the uncertainties, bounded trajectories generated to quantify the uncertainties. The proposed controller considers these scenarios in a risk-sensitive manner. A certainty equivalent nonlinear model predictive control based on minimum principle is reformulated to optimise nominal cost and expected value of future recourse actions. The capability of proposed method in terms of states regulations, constraints fulfilment, and real-time implementation is demonstrated for a semi-autonomous ecological advanced driver assistance system specified for battery electric vehicles. This system plans for a safe and energy-efficient cruising velocity profile autonomously. [less ▲]

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See detailRisk, safety and assistive technology in the context of ageing-in-place
Lamotte, Mathilde UL; Ferring, Dieter UL; Tournier, Isabelle UL

Scientific Conference (2017, July 06)

When speaking about ageing in place, risk of accidents and subsequent injuries is an important part of individual worries, and risk avoidance or risk minimisation are main concerns of older people and ... [more ▼]

When speaking about ageing in place, risk of accidents and subsequent injuries is an important part of individual worries, and risk avoidance or risk minimisation are main concerns of older people and their caregivers. Findings show that older people are more at risk of unintended injuries than younger people (i.e. falls, foodborne diseases). Moreover, individual concerns and associated worries to avoid specific risks may even lead to the decision to move to an institution. In this context it is important to consider that being “as safe as possible” with respect to objective parameters does not necessarily indicate the subjective feeling of being safe. The feeling of safety and the objective degree of safety are not linearly related in a way that increasing one factor will increase the other and conversely. Furthermore, some factors that can contribute to objectively enhance safety may even lead to greater feeling of unsafety. Our review aims to investigate the relationship between objective and subjective safety in the context of ageing in place as well as the underlying mechanisms that help to explain the different links between objective and subjective safety. A further goal is offer a heuristic model presenting factors that may help to enhance older people’s consciousness of safety and thus quality of life. These include individual as well as social and macro-social factors. This paper focusses individual factors and will especially highlight the role of older people’s daily routines and their impact on technology acceptance. [less ▲]

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See detailThe Quest for Questions in Digital History: A Comparative View on Werner- and Delors Report on Economic and Monetary Union
Armaselu, Florentina UL; Danescu, Elena UL

Scientific Conference (2017, July 05)

Starting from Gaston Bachelard’s assumption that “all knowledge is an answer to a question”, the study proposes the use of comparative textual analysis to formulate research questions. A set of questions ... [more ▼]

Starting from Gaston Bachelard’s assumption that “all knowledge is an answer to a question”, the study proposes the use of comparative textual analysis to formulate research questions. A set of questions were derived via the TXM, Textométrie software, a tool for lexicometry and statistical analysis. Two historical documents on the Economic and Monetary Union (EMU) were examined, the Werner report and the Delors report (French versions). The “quest for questions” was based on the comparison of the documents, using the TXM specificities feature that highlights what properties are specific, as overuse or deficit, to a part versus the rest of a corpus. The documents were analysed both as entire units and as fragments (numbered parts and sections). The specificities were computed for the noun-adjective combination and parts of speech, the properties with specificity scores higher and lower than the TXM default positive and negative banality thresholds being selected for further enquiry and subsequently used to formulate research questions. Although further experiments, testing with other corpora and theoretical formalisation are required, the first results show that digital tools may serve not only as hypotheses or conclusions validators but also as means of discovering exploration paths to support interpretation and the construction of new knowledge in digital history. [less ▲]

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See detailSelf-care Assistive Technologies: A systematic review of studies on efficiency and factors influencing their use
Abrilahij, Afsaneh UL; Boll, Thomas UL; Ferring, Dieter UL

Scientific Conference (2017, July 05)

A gradual decline in functional and mental capacity, as well as a growing risk of care dependency constitute major concerns of life in old age. These are expected to become more urgent in the future ... [more ▼]

A gradual decline in functional and mental capacity, as well as a growing risk of care dependency constitute major concerns of life in old age. These are expected to become more urgent in the future, because the old-age dependency ratio in the EU is projected to nearly double until 2060 due to demographic change. On the other side, there is a strong desire to maintain the autonomy of older people as long as possible. In reaction to this, there have been strong health and social policy recommendations across Europe to develop and promote the use of assistive technologies (ATs). Whereas systematic reviews already exist for several kinds of ATs, reviews about self-care ATs are still missing. Based on a systematic literature search in PsycINFO, MEDLINE, and Google Scholar databases 203 papers were identified of which 13 were included according to our selection criteria. The methodological quality of all the reviewed studies is evaluated. We reviewed findings on objective and subjective indicators of independent living as efficiency criteria as well as evidence about facilitating and inhibiting factors in the use of these technologies. Self-care ATs turned out to be efficient, with respect to care hours, independence level, and self-reported satisfaction. The actual use of these ATs was influenced by diverse personal, contextual, and device aspects. Lack of randomized control trial studies and the need for a further research about ATs in the diverse subdomains of self-care activities is revealed. Based on the findings of the current study, we generate recommendations for future research. [less ▲]

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See detailOn the Scientific Applications of IGS Products: An Assessment of the Reprocessed TIGA Solutions and Combined Products
Hunegnaw, Addisu UL; Teferle, Felix Norman UL; Abraha, Kibrom Ebuy UL et al

Scientific Conference (2017, July 03)

Global sea levels have risen since the early 19th century and this rise is likely to accelerate through the 21st century and beyond. Much of the past information on sea level rise stems from the ... [more ▼]

Global sea levels have risen since the early 19th century and this rise is likely to accelerate through the 21st century and beyond. Much of the past information on sea level rise stems from the instrumental records of tide gauges, which measure changes in sea level relative to a tide gauge benchmark (TGBM) situated on land. In order to assess regional or global sea level changes the vertical land movements (VLM) at the tide gauge and its TGBM need to be monitored. GNSS, in particular GPS, has been recognized as one space-geodetic technique to provide highly accurate estimates of VLM in a geocentric reference frame for tide gauges and their TGBMs. As it turned out, this scientific application of GNSS poses the most stringent requirements on the consistency and homogeneity on the data, processing strategies, satellite products, bias models and reference frames used in the analysis of GNSS measurements. Under the umbrella of the International GNSS Service (IGS), the Tide Gauge Benchmark Monitoring (TIGA) Working Group (WG) has the objective to provide highly-accurate positions and VLM estimates for a global network of tide gauges contributing to the Global Sea Level Observing System (GLOSS) and the Permanent Service for Mean Sea Level (PSMSL). As such TIGA forms an important contribution of the IGS to the goals of the Global Geodetic Observing System (GGOS), the Global Climate Observing System (GCOS) and the World Climate Research Programme (WCRP). To achieve the TIGA-WG objectives, five TIGA Analysis Centers (TACs) contributed re-processed global GPS network solutions to TIGA, employing the latest bias models and processing strategies in accordance with the second IGS re-processing campaign (repro2). These individual TAC solutions were then used to compute the combined products by the TIGA Combination Centre (TCC) at the University of Luxembourg using an in-house modified version of the CATREF software package. In this study, we present and internally evaluate the individual TAC and TIGA combined products. We investigate station positions, scale and origin biases, including their frequency content. We also externally evaluate the combined products, particularly the VLM estimates, using solutions from the ITRF2008, ITRF2014 and the glacial isostatic adjustment model ICE-6G (VM5a). Finally, we draw some conclusions on the recent advances and remaining limitations of the various IGS products required for the challenging application to sea level studies. [less ▲]

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See detailMagnetic neutron scattering on Nd-Fe-B magnets
Michels, Andreas UL

Scientific Conference (2017, July 02)

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See detailEnergy-Efficient Design for Edge-caching Wireless Networks: When is Coded-caching beneficial?
Vu, Thang Xuan UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in Abstract book of IEEE 18th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC) (2017, July)

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See detailTo use or not to use? Investigating the validity argument for the use of short scales in research settings
Kemper, Christoph UL; Becker, N.; Baudson, T. G. et al

Scientific Conference (2017, July)

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See detailProceedings of International Conference on Software and Systems Process (ICSSP)
Kuhrmann, Marco; Diebold, Philipp; Münch, Jürgen et al

in Hybrid software and system development in practice: Waterfall, scrum, and beyond (2017, July)

Software and system development faces numerous challenges of rapidly changing markets. To address such challenges, companies and projects design and adopt specific development approaches by combining well ... [more ▼]

Software and system development faces numerous challenges of rapidly changing markets. To address such challenges, companies and projects design and adopt specific development approaches by combining well-structured comprehensive methods and flexible agile practices. Yet, the number of methods and practices is large, and available studies argue that the actual process composition is carried out in a fairly ad-hoc manner. The present paper reports on a survey on hybrid software development approaches. We study which approaches are used in practice, how different approaches are combined, and what contextual factors influence the use and combination of hybrid software development approaches. Our results from 69 study participants show a variety of development approaches used and combined in practice. We show that most combinations follow a pattern in which a traditional process model serves as framework in which several fine-grained (agile) practices are plugged in. We further show that hybrid software development approaches are independent from the company size and external triggers. We conclude that such approaches are the results of a natural process evolution, which is mainly driven by experience, learning, and pragmatism. [less ▲]

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See detailProfiles of students on account of complex problem solving strategies
Gnaldi, M.; Bacci, S.; Greiff, Samuel UL et al

Scientific Conference (2017, July)

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See detailTowards Semantic Interoperability in an Open IoT Ecosystem for Connected Vehicle Services
Kolbe, Niklas UL; Kubler, Sylvain UL; Robert, Jérémy UL et al

in 2017 IEEE Global Internet of Things Summit (GIoTS) Proceedings (2017, July)

A present challenge in today’s Internet of Things (IoT) ecosystem is to enable interoperability across hetero- geneous systems and service providers. Restricted access to data sources and services limits ... [more ▼]

A present challenge in today’s Internet of Things (IoT) ecosystem is to enable interoperability across hetero- geneous systems and service providers. Restricted access to data sources and services limits the capabilities of a smart city to improve social, environmental and economic aspects. Interoperability in the IoT is concerned with both, messaging interfaces and semantic understanding of heterogeneous data. In this paper, the first building blocks of an emerging open IoT ecosystem developed at the EU level are presented. Se- mantic web technologies are applied to the existing messaging components to support and improve semantic interoperability. The approach is demonstrated with a proof-of-concept for connected vehicle services in a smart city setting. [less ▲]

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See detailEnriching a Situation Awareness Framework for IoT with Knowledge Base and Reasoning Components
Kolbe, Niklas UL; Zaslavsky, Arkady; Kubler, Sylvain UL et al

in Modeling and Using Context (2017, July)

Theimportanceofsystem-levelcontext-andsituationaware- ness increases with the growth of the Internet of Things (IoT). This paper proposes an integrated approach to situation awareness by providing a ... [more ▼]

Theimportanceofsystem-levelcontext-andsituationaware- ness increases with the growth of the Internet of Things (IoT). This paper proposes an integrated approach to situation awareness by providing a semantically rich situation model together with reliable situation infer- ence based on Context Spaces Theory (CST) and Situation Theory (ST). The paper discusses benefits of integrating the proposed situation aware- ness framework with knowledge base and efficient reasoning techniques taking into account uncertainty and incomplete knowledge about situa- tions. The paper discusses advantages and impact of proposed context adaptation in dynamic IoT environments. Practical issues of two-way mapping between IoT messaging standards and CST are also discussed. [less ▲]

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See detailImpact of Tool Support in Patch Construction
Koyuncu, Anil UL; Bissyande, Tegawendé François D Assise UL; Kim, Dongsun UL et al

Scientific Conference (2017, July)

In this work, we investigate the practice of patch construction in the Linux kernel development, focusing on the differences between three patching processes: (1) patches crafted entirely manually to fix ... [more ▼]

In this work, we investigate the practice of patch construction in the Linux kernel development, focusing on the differences between three patching processes: (1) patches crafted entirely manually to fix bugs, (2) those that are derived from warnings of bug detection tools, and (3) those that are automatically generated based on fix patterns. With this study, we provide to the research community concrete insights on the practice of patching as well as how the development community is currently embracing research and commercial patching tools to improve productivity in repair. The result of our study shows that tool-supported patches are increasingly adopted by the developer community while manually-written patches are accepted more quickly. Patch application tools enable developers to remain committed to contributing patches to the code base. Our findings also include that, in actual development processes, patches generally implement several change operations spread over the code, even for patches fixing warnings by bug detection tools. Finally, this study has shown that there is an opportunity to directly leverage the output of bug detection tools to readily generate patches that are appropriate for fixing the problem, and that are consistent with manually-written patches. [less ▲]

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See detailNumerical Check of the Meyerhof Bearing Capacity Equation for Shallow Foundations
Van Baars, Stefan UL

in Shehata, Hany; Rashed, Youssef (Eds.) Congress and Exhibition on Sustainable Civil Infrastructures (2017, July)

In 1920 Prandtl published an analytical solution for the bearing capacity of a strip load on a weightless infinite half-space. This solution was extended with a surrounding surcharge by Reissner and with ... [more ▼]

In 1920 Prandtl published an analytical solution for the bearing capacity of a strip load on a weightless infinite half-space. This solution was extended with a surrounding surcharge by Reissner and with the soil weight by Keverling Buisman. It was Terzaghi who wrote this with three separate bearing capacity factors for the cohesion, surcharge and soil-weight. Meyerhof extended this to the equation which is nowadays used; with shape and inclination factors. He also proposed equations for the inclination factors, based on his own laboratory experiments. Since then, several people proposed updated equations for the soil-weight bearing capacity factor, and also for the shape and inclination factors. The common idea is that failure of a footing occurs in all cases with a Prandtl-wedge failure mechanism. In order to check the failure mechanisms and the currently used equations for the bearing capacity factors and shape factors, a large number of finite element calculations of strip and circular footings have been made. These calculations proof that for some cases there are also a few other failure mechanisms possible. Also the currently used bearing capacity factors and shape factors are not correct. In fact, for footings on a soil with a higher friction angle, all three bearing capacity factors and all three shape factors can be much lower than the currently used values. This means that the currently used equations for the soil-weight bearing capacity factors and the shape factors are inaccurate and unsafe. Therefore, based on the finite element calculations, new equations have been presented in this paper. [less ▲]

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See detailAnalyzing Complex Data in Motion at Scale with Temporal Graphs
Hartmann, Thomas UL; Fouquet, François UL; Jimenez, Matthieu UL et al

in Proceedings of the 29th International Conference on Software Engineering and Knowledge Engineering (2017, July)

Modern analytics solutions succeed to understand and predict phenomenons in a large diversity of software systems, from social networks to Internet-of-Things platforms. This success challenges analytics ... [more ▼]

Modern analytics solutions succeed to understand and predict phenomenons in a large diversity of software systems, from social networks to Internet-of-Things platforms. This success challenges analytics algorithms to deal with more and more complex data, which can be structured as graphs and evolve over time. However, the underlying data storage systems that support large-scale data analytics, such as time-series or graph databases, fail to accommodate both dimensions, which limits the integration of more advanced analysis taking into account the history of complex graphs, for example. This paper therefore introduces a formal and practical definition of temporal graphs. Temporal graphs pro- vide a compact representation of time-evolving graphs that can be used to analyze complex data in motion. In particular, we demonstrate with our open-source implementation, named GREYCAT, that the performance of temporal graphs allows analytics solutions to deal with rapidly evolving large-scale graphs. [less ▲]

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See detailPower Allocation for In-Band Full-Duplex Self-Backhauling
Lagunas, Eva UL; Lei, Lei UL; Maleki, Sina UL et al

in International Conference on Telecommunications and Signal Processing (TSP), Barcelona, Spain, July 2017 (2017, July)

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See detailProbability signatures of multistate systems made up of two-state components
Marichal, Jean-Luc UL; Mathonet, Pierre; Jorge, Navarro et al

Scientific Conference (2017, July)

The structure signature of a system made up of $n$ components having continuous and i.i.d. lifetimes was defined in the eighties by Samaniego as the $n$-tuple whose $k$-th coordinate is the probability ... [more ▼]

The structure signature of a system made up of $n$ components having continuous and i.i.d. lifetimes was defined in the eighties by Samaniego as the $n$-tuple whose $k$-th coordinate is the probability that the $k$-th component failure causes the system to fail. More recently, a bivariate version of this concept was considered as follows. The joint structure signature of a pair of systems built on a common set of components having continuous and i.i.d. lifetimes is a square matrix of order $n$ whose $(k,l)$-entry is the probability that the $k$-th failure causes the first system to fail and the $l$-th failure causes the second system to fail. This concept was successfully used to derive a signature-based decomposition of the joint reliability of the two systems. In this talk we will show an explicit formula to compute the joint structure signature of two or more systems and extend this formula to the general non-i.i.d. case, assuming only that the distribution of the component lifetimes has no ties. Then we will discuss a condition on this distribution for the joint reliability of the systems to have a signature-based decomposition. Finally we will show how these results can be applied to the investigation of the reliability and signature of multistate systems made up of two-state components. [less ▲]

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See detailSpatial PAPR Reduction in Symbol-level Precoding for the Multi-beam Satellite Downlink
Spano, Danilo UL; Alodeh, Maha UL; Chatzinotas, Symeon UL et al

in IEEE SPAWC 2017 (2017, July)

In this work, a novel symbol-level precoding scheme is proposed, for managing the multi-user interference in the forward downlink channel of a multi-beam satellite system. Besides exploiting the ... [more ▼]

In this work, a novel symbol-level precoding scheme is proposed, for managing the multi-user interference in the forward downlink channel of a multi-beam satellite system. Besides exploiting the constructive interference effect, the proposed scheme aims at improving the robustness of the transmitted signals to the non-linear distortions of practical satellite systems. This is done by reducing the imbalances between the instantaneous power transmitted by the multiple antennas, which are detrimental in non-linear systems. More specifically, this work proposes a symbol-level precoding scheme performing the minimization of the spatial peak-to-average power ratio, under Quality-of-Service constraints. An iterative algorithm is proposed to solve the related optimization problem. Numerical results are presented to assess the performance of the proposed scheme, which outperforms the state of the art symbol-level precoding techniques in terms of spatial peak-to-average power ratio across the transmitting antennas. [less ▲]

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See detailFast Stochastic Non-linear Model Predictive Control for Electric Vehicle Advanced Driver Assistance Systems
Sajadi Alamdari, Seyed Amin UL; Voos, Holger UL; Darouach, Mohamed

in 13th IEEE International Conference on Vehicular Electronics and Safety, Vienna, Austria 27-28 June 2017 (2017, June 27)

Semi-autonomous driving assistance systems have a high potential to improve the safety and efficiency of the battery electric vehicles that are enduring limited cruising range. This paper presents an ... [more ▼]

Semi-autonomous driving assistance systems have a high potential to improve the safety and efficiency of the battery electric vehicles that are enduring limited cruising range. This paper presents an ecologically advanced driver assistance system to extend the functionality of the adaptive cruise control system. A real-time stochastic non-linear model predictive controller with probabilistic constraints is presented to compute on-line the safe and energy-efficient cruising velocity profile. The individual chance-constraint is reformulated into a convex second-order cone constraint which is robust for a general class of probability distributions. Finally, the performance of proposed approach in terms of states regulation, constraints fulfilment, and energy efficiency is evaluated on a battery electric vehicle. [less ▲]

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See detailThe CSD and its influence on labour law in Europe
Ratti, Luca UL

Scientific Conference (2017, June 26)

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See detailHow Mobile Phone Handovers reflect Urban Mobility: A Simulation Study
Derrmann, Thierry UL; Frank, Raphaël UL; Engel, Thomas UL et al

in Derrmann, Thierry; Frank, Raphaël; Engel, Thomas (Eds.) et al How Mobile Phone Handovers reflect Urban Mobility: A Simulation Study (2017, June 26)

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See detailThe effect of training morphosyntactic markers in German and in French on multilingual fifth-graders' spelling.
Bilici, Natalia UL; Ugen, Sonja UL; Weth, Constanze UL

Scientific Conference (2017, June 26)

Many studies focussing on spelling in French and German languages show that, even by the end of the primary school, pupils have difficulties to encode morphosyntactic information in their writing ... [more ▼]

Many studies focussing on spelling in French and German languages show that, even by the end of the primary school, pupils have difficulties to encode morphosyntactic information in their writing. Particularly problematic are, for instance, capitalisation of nouns in German (Betzel 2014) or plural markers in French (Fayol et al. 2006), because they are inaudible and require knowledge that goes beyond simple phoneme-grapheme correspondences. Our paper presents how multilingual learners deal with silent morphosyntactic markers in French and German and shows the effects of an intervention training on children's spelling performance. In total our study included 228 multilingual fifth graders (mean age 11 years) with four years instruction in German and two years instruction in French. They were assigned to an intervention (n=137) and to a control group (n=91) based on the results of a spelling test in French and German. This was done by creating performance groups that were, in a second step, attributed to one of the experimental groups taking their performance into account (quasi-randomised procedure). The French test consisted of three word categories of different difficulty (nouns, verbs, adjectives). For adjectives only, position (pre- vs. post-nominal) was also manipulated. The German test focussed on three lexical-semantic characteristics (concrete nouns, abstract nouns, nominalizations) and four syntactical positions (determinant+noun, determinant+adjective+noun, adjective+noun, noun) frequent words and pseudo-words. Additionally, word frequency was manipulated within each language (frequent words vs. pseudowords). These difficulty levels have been based on the literature published on monolingual learners (French: Totereau et al. (2014), German: Funke (2005); Guenther (2007); Betzel (2014)). The children participated in 12 intervention sessions of 20 minutes each (six in German and six in French, the order was counterbalanced). Children of the intervention group were trained to improve their morphosyntactic awareness and thus spelling performance of French plurals and German capitalization. The control group received the same amount of language input than the intervention group, but they were trained on another aspect of language i.e. listening comprehension. Results from the pre-test show that multilingual children acquiring German and French show similar difficulty patterns as German or French monolinguals. The post-test shows that the intervention group improved significantly in both their German and French spelling in comparison to the control group in all word and pseudo-word categories and positions. The intervention group's performance increased especially on pseudo-words, indicating that the training had an effect on children's spelling according to syntactic regularities. The study results are specifically important to better understand the learning processes of morphosyntactic spelling in primary school. The implications on the teaching methods will be discussed. [less ▲]

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See detailASIMUT project: Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques
Bouvry, Pascal UL; Chaumette, Serge; Danoy, Grégoire UL et al

in DroNet'17 Proceedings of the 3rd Workshop on Micro Aerial Vehicle Networks, Systems, and Applications (2017, June 23)

This document summarizes the activities and results of the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques) carried out by the consortium ... [more ▼]

This document summarizes the activities and results of the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques) carried out by the consortium composed of Thales, Fraunhofer IOSB, Fly-n-Sense, University of Bordeaux and University of Luxembourg. Funded by the European Defence Agency (EDA), the objectives of the ASIMUT project are to design, implement and validate algorithms that will allow the efficient usage of autonomous swarms of Unmanned Aerial Vehicles (UAVs) for surveillance missions. [less ▲]

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