References of "Paper published in a journal"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailTopologie culinaire au cinéma : le lieu commun du repas et ses déclinaison
Roelens, Nathalie UL

in Bibliothèque électronique Paris 8 (in press)

Detailed reference viewed: 132 (9 UL)
Full Text
Peer Reviewed
See detailA Look into Privacy-Preserving Blockchains
Khan, Nida UL; Nassar, Mohamed

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

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

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

Detailed reference viewed: 79 (13 UL)
Full Text
Peer Reviewed
See detailBack to the Moon: Legal Challenges for Future Lunar Exploration
Salmeri, Antonino UL

in Proceedings of the International Institute of Space Law (in press)

In the light of the recently renovated interest in returning humans to the Moon, this paper addresses the main legal challenges related, with the goal to show practical solutions under the current system ... [more ▼]

In the light of the recently renovated interest in returning humans to the Moon, this paper addresses the main legal challenges related, with the goal to show practical solutions under the current system of international space law. In order to do so, the paper first presents an overview of current lunar exploration programs, arguing that public and private missions raise different challenges and thus require specific models. Following, it accordingly assesses possible legal solutions for the regulation of these programs. On the one hand, States’ exploration programs may be governed by a revised version of the Intergovernmental Agreement already concluded for the International Space Station. On the other hand, private activities could be better organized relying on Articles VI-IX OST as integrated by a new UNGA Resolution, ad hoc bilateral agreements and specific provisions in national space legislations. Finally, the paper concludes underlining the importance of international cooperation as the key to ensure the peaceful use and exploration of outer space. [less ▲]

Detailed reference viewed: 49 (1 UL)
Full Text
Peer Reviewed
See detailVisualization of AE's Training on Credit Card Transactions with Persistent Homology
Charlier, Jérémy Henri J. UL; Petit, François UL; Ormazabal, Gaston et al

in Proceedings of the International Workshop on Applications of Topological Data Analysis In conjunction with ECML PKDD 2019 (2019, September)

Auto-encoders are among the most popular neural network architecture for dimension reduction. They are composed of two parts: the encoder which maps the model distribution to a latent manifold and the ... [more ▼]

Auto-encoders are among the most popular neural network architecture for dimension reduction. They are composed of two parts: the encoder which maps the model distribution to a latent manifold and the decoder which maps the latent manifold to a reconstructed distribution. However, auto-encoders are known to provoke chaotically scattered data distribution in the latent manifold resulting in an incomplete reconstructed distribution. Current distance measures fail to detect this problem because they are not able to acknowledge the shape of the data manifolds, i.e. their topological features, and the scale at which the manifolds should be analyzed. We propose Persistent Homology for Wasserstein Auto-Encoders, called PHom-WAE, a new methodology to assess and measure the data distribution of a generative model. PHom-WAE minimizes the Wasserstein distance between the true distribution and the reconstructed distribution and uses persistent homology, the study of the topological features of a space at different spatial resolutions, to compare the nature of the latent manifold and the reconstructed distribution. Our experiments underline the potential of persistent homology for Wasserstein Auto-Encoders in comparison to Variational Auto-Encoders, another type of generative model. The experiments are conducted on a real-world data set particularly challenging for traditional distance measures and auto-encoders. PHom-WAE is the first methodology to propose a topological distance measure, the bottleneck distance, for Wasserstein Auto-Encoders used to compare decoded samples of high quality in the context of credit card transactions. [less ▲]

Detailed reference viewed: 31 (4 UL)
Full Text
Peer Reviewed
See detailParametric strudy on non-ductile demountable shear connectors
Odenbreit, Christoph UL; Kozma, Andras UL

in ce/papers (2019, September), 3(3-4), 283-288

The basic principle of the circular economy is to reduce or totally eliminate waste and carbon dioxide production with the help of a multiple, efficient usage of resources. The application of reusable ... [more ▼]

The basic principle of the circular economy is to reduce or totally eliminate waste and carbon dioxide production with the help of a multiple, efficient usage of resources. The application of reusable structural elements plays an important role and can contribute essentially to a low-carbon future. Within the European research project REDUCE (Grant Agreement number: 710040), composite beams and steel-based flooring systems, which are demountable and reusable, have been developed and investigated. The experimental investigations showed that the structural behaviour of the newly developed shear connectors differs from the behaviour of the traditionally applied welded studs. Some behave in a non-ductile way. In order to assess, how far the regulations of EN1994-1-1 for shear connections can still be applied, parametric studies have been conducted. The respective numerical models were developed with the use of the commercially available finite element software ABAQUS® and were validated against the experimental observations. The effects of the lack of ductility of the shear connectors on the structural behaviour of the entire composite beam was examined with different types of shear connectors, shear connector layouts and material grades. This contribution presents the underlying laboratory tests as well as the results of the supplementing numerical parameter studies. The outcome provides valuable information for future design guidance concerning the use of demountable shear connectors in composite beams. [less ▲]

Detailed reference viewed: 11 (3 UL)
Full Text
Peer Reviewed
See detailDifferent load‐bearing mechanisms in headed stud shear connections in composite beams with profiled steel sheeting
Vigneri, Valentino UL; Odenbreit, Christoph UL; Lam, Dennis

in ce/papers (2019, September), 3(3-4), 231-236

The current regulations of EN1994-1-1 for headed stud shear connections in composite beams with profiled sheeting lead, for some configurations, to an over-estimation of the load-bearing capacity. Since ... [more ▼]

The current regulations of EN1994-1-1 for headed stud shear connections in composite beams with profiled sheeting lead, for some configurations, to an over-estimation of the load-bearing capacity. Since these design equations are based on empirical considerations, they are not able to capture the real mechanical behaviour of the connector and they do not consider appropriately the influence of the geometry of sheeting on the shear capacity. For this reason, the load-bearing mechanisms of the shear connection are identified in this work with the support of experimental and numerical results. According to the static system presented, the concrete rib is modelled as a system of diagonal struts acting simultaneously in combination with the stud in bending. It is observed that at 2÷4 mm slip, a ?Strut and beam? mechanism prevails where the resistance of the connector depends mostly on the plastic hinges activated in the stud and on the capacity of the diagonal strut in front of it. By increasing the slip (ca. 4÷10 mm), the surrounding concrete progressively crushes while the tensile stresses at the edge of the rib reach the tensile strength of the material. As a consequence of this loss of rotational stiffness, the bending capacity developed in the stud reduces and the upper hinges gradually moves towards the slab. At higher displacements (ca. 20÷40 mm), due to nonlinear geometric effects, high tensile forces develop in the stud and the load is carried through a ?Strut and Tie? resistance mechanism, if the embedment of the stud is sufficient. By further increasing the slip, the whole rib rotates or the failure occurs either for concrete pull-out or stud rupture. This contribution describes the sequence of the activated load-bearing mechanisms in headed stud shear connections with profiled steel sheeting at different displacements. [less ▲]

Detailed reference viewed: 37 (12 UL)
Full Text
Peer Reviewed
See detailMQLV: Optimal Policy of Money Management in Retail Banking with Q-Learning
Charlier, Jérémy Henri J. UL; Ormazabal, Gaston; State, Radu UL et al

in Proceedings of the Fourth Workshop on MIning DAta for financial applicationS (MIDAS 2019) co-located with the 2019 European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECML-PKDD 2019) (2019, September)

Reinforcement learning has become one of the best approach to train a computer game emulator capable of human level performance. In a reinforcement learning approach, an optimal value function is learned ... [more ▼]

Reinforcement learning has become one of the best approach to train a computer game emulator capable of human level performance. In a reinforcement learning approach, an optimal value function is learned across a set of actions, or decisions, that leads to a set of states giving different rewards, with the objective to maximize the overall reward. A policy assigns to each state-action pairs an expected return. We call an optimal policy a policy for which the value function is optimal. QLBS, Q-Learner in the Black-Scholes(-Merton) Worlds, applies the reinforcement learning concepts, and noticeably, the popular Q-learning algorithm, to the financial stochastic model of Black, Scholes and Merton. It is, however, specifically optimized for the geometric Brownian motion and the vanilla options. Its range of application is, therefore, limited to vanilla option pricing within the financial markets. We propose MQLV, Modified Q-Learner for the Vasicek model, a new reinforcement learning approach that determines the optimal policy of money management based on the aggregated financial transactions of the clients. It unlocks new frontiers to establish personalized credit card limits or bank loan applications, targeting the retail banking industry. MQLV extends the simulation to mean reverting stochastic diffusion processes and it uses a digital function, a Heaviside step function expressed in its discrete form, to estimate the probability of a future event such as a payment default. In our experiments, we first show the similarities between a set of historical financial transactions and Vasicek generated transactions and, then, we underline the potential of MQLV on generated Monte Carlo simulations. Finally, MQLV is the first Q-learning Vasicek-based methodology addressing transparent decision making processes in retail banking. [less ▲]

Detailed reference viewed: 39 (3 UL)
Full Text
Peer Reviewed
See detailARCHITECTURES AND SYNCHRONIZATION TECHNIQUES FOR COHERENT DISTRIBUTED REMOTE SENSING SYSTEMS
Merlano Duncan, Juan Carlos UL; Querol Borras, Jorge UL; Camps, Adriano et al

in 2019 IEEE International Geoscience and Remote Sensing Symposium (IGARSS) (2019, August 31)

Phase, frequency and time synchronization is a crucial requirement for many applications as such as multi-static remote sensing and distributed beamforming for communications. The literature on the field ... [more ▼]

Phase, frequency and time synchronization is a crucial requirement for many applications as such as multi-static remote sensing and distributed beamforming for communications. The literature on the field is very wide, and in some cases, the requirements of the proposed synchronization solution may surpass the ones set by the application itself. Moreover, the synchronization solution becomes even more challenging when the nodes are flying or hovering on aerial or space platforms. In this work, we compare and classify the synchronization technologies available in the literature according to a common proposed framework, and we discuss the considerations of an implementation for distributed remote sensing applications. The general framework considered is based on a distributed collection of autonomous nodes that try to synchronize their clocks with a common reference. Moreover, they can be classified in non-overlapping, adjacent and overlapping frequency band scenarios [less ▲]

Detailed reference viewed: 43 (3 UL)
Full Text
Peer Reviewed
See detailA Model-driven Approach to Trace Checking of Temporal Properties with Aggregations
Boufaied, Chaima UL; Bianculli, Domenico UL; Briand, Lionel UL

in Journal of Object Technology (2019, July), 18(2), 151-21

The verification of complex software systems often requires to check quantitative properties that rely on aggregation operators (e.g., the average response time of a service). One way to ease the ... [more ▼]

The verification of complex software systems often requires to check quantitative properties that rely on aggregation operators (e.g., the average response time of a service). One way to ease the specification of these properties is to use property specification patterns, such as the ones for “service provisioning”, previously proposed in the literature. In this paper we focus on the problem of performing offline trace checking of temporal properties containing aggregation operators. We first present TemPsy-AG, an extension of TemPsy—an existing pattern-based language for the specification of temporal properties—to support service provisioning patterns that use aggregation operators. We then extend an existing model-driven procedure for trace checking, to verify properties expressed in TemPsy-AG. The trace checking procedure relies on the efficient mapping of temporal properties written in TemPsy-AG into OCL constraints on a meta-model of execution traces. We have implemented this procedure in the TemPsy-Check-AG tool and evaluated its performance: our approach scales linearly with respect to the length of the input trace and can deal with much larger traces than a state-of-the-art tool. [less ▲]

Detailed reference viewed: 129 (20 UL)
Full Text
Peer Reviewed
See detailTogether or Alone: The Price of Privacy in Collaborative Learinig
Pejo, Balazs UL; Tang, Qiang; Biczók, Gergely

in Proceedings on Privacy Enhancing Technologies (2019, July)

Machine learning algorithms have reached mainstream status and are widely deployed in many applications. The accuracy of such algorithms depends significantly on the size of the underlying training ... [more ▼]

Machine learning algorithms have reached mainstream status and are widely deployed in many applications. The accuracy of such algorithms depends significantly on the size of the underlying training dataset; in reality a small or medium sized organization often does not have the necessary data to train a reasonably accurate model. For such organizations, a realistic solution is to train their machine learning models based on their joint dataset (which is a union of the individual ones). Unfortunately, privacy concerns prevent them from straightforwardly doing so. While a number of privacy-preserving solutions exist for collaborating organizations to securely aggregate the parameters in the process of training the models, we are not aware of any work that provides a rational framework for the participants to precisely balance the privacy loss and accuracy gain in their collaboration. In this paper, by focusing on a two-player setting, we model the collaborative training process as a two-player game where each player aims to achieve higher accuracy while preserving the privacy of its own dataset. We introduce the notion of Price of Privacy, a novel approach for measuring the impact of privacy protection on the accuracy in the proposed framework. Furthermore, we develop a game-theoretical model for different player types, and then either find or prove the existence of a Nash Equilibrium with regard to the strength of privacy protection for each player. Using recommendation systems as our main use case, we demonstrate how two players can make practical use of the proposed theoretical framework, including setting up the parameters and approximating the non-trivial Nash Equilibrium. [less ▲]

Detailed reference viewed: 75 (3 UL)
Full Text
See detailUser Experience challenges for designing and evaluating Computer-Based Assessments for children
Lehnert, Florence Kristin UL

in IDC '19 Proceedings of the 18th ACM International Conference on Interaction Design and Children (2019, June 12)

Computer-Based Assessment (CBA), i.e., the use of computers instead of paper & pencil for testing purposes is now increasingly used, both in education and in the workforce. Along with this trend, several ... [more ▼]

Computer-Based Assessment (CBA), i.e., the use of computers instead of paper & pencil for testing purposes is now increasingly used, both in education and in the workforce. Along with this trend, several issues regarding the usage of computers in assessment can be raised. With respect to CBA, test validity and acceptance appear at stake during interacting with a complex assessment system. For instance, individual differences in computer literacy (i.e. ability to handle technology) might cause different outcomes that are not related to the problem-solving task. Prior investigation has shown that there is a scarcity of research on the User Experience (UX) in the context of CBA, also due to a focus on adult users. This doctoral thesis aims to adapt and develop new evaluation methods from the Human-Computer Interaction (HCI) field, applied in the context of CBA. The contributions will result in the development of best practices guidelines for both research and practitioners by adopting design and evaluation methods drawn from the field of Child-computer Interaction (CCI). [less ▲]

Detailed reference viewed: 79 (5 UL)
Full Text
See detailTowards a high-resolution drone-based 3D mapping dataset to optimise flood hazard modelling
Backes, Dietmar UL; Schumann, Guy; Teferle, Felix Norman UL et al

in International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences (2019, June), XLII-2/W13

The occurrence of urban flooding following strong rainfall events may increase as a result of climate change. Urban expansion, ageing infrastructure and an increasing number of impervious surfaces are ... [more ▼]

The occurrence of urban flooding following strong rainfall events may increase as a result of climate change. Urban expansion, ageing infrastructure and an increasing number of impervious surfaces are further exacerbating flooding. To increase resilience and support flood mitigation, bespoke accurate flood modelling and reliable prediction is required. However, flooding in urban areas is most challenging. State-of-the-art flood inundation modelling is still often based on relatively low-resolution 2.5 D bare earth models with 2-5m GSD. Current systems suffer from a lack of precise input data and numerical instabilities and lack of other important data, such as drainage networks. Especially, the quality and resolution of the topographic input data represents a major source of uncertainty in urban flood modelling. A benchmark study is needed that defines the accuracy requirements for highly detailed urban flood modelling and to improve our understanding of important threshold processes and limitations of current methods and 3D mapping data alike. This paper presents the first steps in establishing a new, innovative multiscale data set suitable to benchmark urban flood modelling. The final data set will consist of high-resolution 3D mapping data acquired from different airborne platforms, focusing on the use of drones (optical and LiDAR). The case study includes residential as well as rural areas in Dudelange/Luxembourg, which have been prone to localized flash flooding following strong rainfall events in recent years. The project also represents a cross-disciplinary collaboration between the geospatial and flood modelling community. In this paper, we introduce the first steps to build up a new benchmark data set together with some initial flood modelling results. More detailed investigations will follow in the next phases of this project. [less ▲]

Detailed reference viewed: 52 (6 UL)
Full Text
Peer Reviewed
See detailPredicting Sparse Clients' Actions with CPOPT-Net in the Banking Environment
Charlier, Jérémy Henri J. UL; State, Radu UL; Hilger, Jean UL

in 32nd Canadian Conference on Artificial Intelligence Proceedings (2019, May)

The digital revolution of the banking system with evolving European regulations have pushed the major banking actors to innovate by a newly use of their clients' digital information. Given highly sparse ... [more ▼]

The digital revolution of the banking system with evolving European regulations have pushed the major banking actors to innovate by a newly use of their clients' digital information. Given highly sparse client activities, we propose CPOPT-Net, an algorithm that combines the CP canonical tensor decomposition, a multidimensional matrix decomposition that factorizes a tensor as the sum of rank-one tensors, and neural networks. CPOPT-Net removes efficiently sparse information with a gradient-based resolution while relying on neural networks for time series predictions. Our experiments show that CPOPT-Net is capable to perform accurate predictions of the clients' actions in the context of personalized recommendation. CPOPT-Net is the first algorithm to use non-linear conjugate gradient tensor resolution with neural networks to propose predictions of financial activities on a public data set. [less ▲]

Detailed reference viewed: 50 (0 UL)
Full Text
Peer Reviewed
See detailComparison of boundary treatments in thermal Lattice Boltzmann simulations of moving particles in fluids
Rosemann, T; Kravets, B; Kruggel-Emden, H et al

in Particle Technology Series (2019, April 09)

Various numerical schemes have been developed in recent years to simulate particle-laden flows. The Lattice Boltzmann method (LBM) has emerged as an efficient tool for direct numerical simulations in ... [more ▼]

Various numerical schemes have been developed in recent years to simulate particle-laden flows. The Lattice Boltzmann method (LBM) has emerged as an efficient tool for direct numerical simulations in which the flow field around the particles can be fully resolved. In the thermal Lattice Boltzmann method not only the flow field but also the temperature field is calculated by using one distribution function for the fluid density and one for the fluid temperature. The treatment of curved solid-fluid boundaries is crucial for the simulation of particulate flows with this method. While several aspects of moving boundaries have been discussed in previous studies for the non-thermal LBM, it remains unknown to what extend these findings are transferable to the thermal LBM. In this work, we consider a 3D thermal LBM with a multiple-relaxation-time (MRT) collision operator and compare different techniques that can be applied to handle the moving boundary. There are three key aspects in the LBM that need to be considered at the boundary: the momentum exchange method calculating the drag force acting upon particles, the bounce-back scheme determining the bounce-back of density distribution functions at a boundary, and the refilling algorithm assigning a value to the unknown density distribution functions at lattice nodes uncovered by the particle. First, we demonstrate how the choice of the technique to address these problems in the flow field impacts the results for the temperature field in the thermal LBM. In a second step, we focus on the thermal side where similar techniques need to be applied. We compare different refilling strategies and bounce-back schemes for the temperature distribution functions and assess heat transfer calculation methods for the particle surface. The performance of these implementations is evaluated by comparing the simulation results in terms of accuracy and stability for a moving particle in a channel flow with a Galilean invariant reference system in which the particle’s position is fixed. We conduct this analysis for various Reynolds and Prandtl numbers to test the applicability of the individual techniques to varying flow conditions. Moreover, we demonstrate the potential of the implementation found to be superior by considering a more complex flow field in a particle packing. Our findings serve as a guideline for choosing suitable moving boundary treatments in thermal LBM simulations of particle-laden flows. [less ▲]

Detailed reference viewed: 122 (25 UL)
Full Text
Peer Reviewed
See detailAn interface resolved immersed boundary method in XDEM for particulate flow simulations
Wu, Mingqiu UL; Peters, Bernhard UL; Rosemann, Tony et al

in International Congress on Particle Technology (2019, April 09)

immersed boundary method (IBM) has recently been used for particulate flows and complex fluid-solid interaction problems. The IBM was first introduced by Peskin to simulate blood flow in a beating heart ... [more ▼]

immersed boundary method (IBM) has recently been used for particulate flows and complex fluid-solid interaction problems. The IBM was first introduced by Peskin to simulate blood flow in a beating heart. Later it has been extended for a different range of applications. The advantages of IBM over the body-fitted method is that it substantially simplified grid generation for immersed geometries, and it is easier to handle moving boundary situations. IBM even allows the use of a stationary and non-deformation background mesh, as well as it reduces the cost of computation by avoiding generation of a body-fitted mesh for each time step. However, the IBM approach is not straightforward to implement and it requires special techniques for cut-off boundary cells as well as special techniques for data point interpolations. Generally, the IBM is classified into two approaches based on the methods of imposing the boundary condition in the immersed body. The first approach is called fictitious domain method with continuous forcing scheme which employs a distributed forcing function to impose a rigidity boundary condition in the solid particle domain. The second one is the discrete forcing approach, which enables a sharp interface to represent the immersed surface. The IBM discussed in this work is a combination of these above two approaches: we first employ the continuous forcing scheme to get a first-step approximation of the immersed body, then use an interpolation polynomial to impose a desired accurate physical boundary for each immersed boundary point based on a least square interpolation reconstruction scheme. Particle motions can be calculated and tracked by solving Newton’s equations of motions using the extended discrete element method (XDEM) while the data of fluid flow properties are obtained by solving the Navier-Stokes equations which govern the fluid phase. Combined this leads to the basic concept of DEM-CFD coupling. Therefore, a particle interface resolved simulation solver is developed by coupling the XDEM and IBM approaches together. Consequently, this solver is then used to handle both static and dynamic particle problems as well as particle packed bed simulations. The validation of the solver can be performed by setting one static sphere in a channel and evaluate the drag coefficients and Strouhal number (when shedding occurs) at various Reynolds [less ▲]

Detailed reference viewed: 98 (24 UL)
Full Text
Peer Reviewed
See detailSecurity – Visible, Yet Unseen? How Displaying Security Mechanisms Impacts User Experience and Perceived Security
Distler, Verena UL; Zollinger, Marie-Laure UL; Lallemand, Carine UL et al

in Proceedings of ACM CHI Conference on Human Factors in Computing Systems (CHI2019) (2019, April)

An unsolved debate in the field of usable security concerns whether security mechanisms should be visible, or blackboxed away from the user for the sake of usability. However, tying this question to ... [more ▼]

An unsolved debate in the field of usable security concerns whether security mechanisms should be visible, or blackboxed away from the user for the sake of usability. However, tying this question to pragmatic usability factors only might be simplistic. This study aims at researching the impact of displaying security mechanisms on user experience (UX) in the context of e-voting. Two versions of an e-voting application were designed and tested using a between-group experimental protocol (N=38). Version D displayed security mechanisms, while version ND did not reveal any security-related information. We collected data on UX using standardised evaluation scales and semi-structured interviews. Version D performed better overall in terms of UX and need fulfilment. Qualitative analysis of the interviews gives further insights into factors impacting perceived security. Our study adds to existing research suggesting a conceptual shift from usability to UX and discusses implications for designing and evaluating secure systems. [less ▲]

Detailed reference viewed: 348 (39 UL)
Full Text
Peer Reviewed
See detailTranslingual Discursive Spaces in Language and Arts Lessons
Degano, Sarah UL

in Literacy Information and Computer Education Journal (2019, March), 10(1), 3094-3102

Flexible multilingual pedagogies such as translanguaging pedagogies are promising stepping stones towards a more equitable access to educational resources for students of different backgrounds. Recent ... [more ▼]

Flexible multilingual pedagogies such as translanguaging pedagogies are promising stepping stones towards a more equitable access to educational resources for students of different backgrounds. Recent research in Luxembourgish preschool, Year 1 and Year 2 classes, show that teachers have begun to implement such pedagogies by encouraging the deployment of the students’ full linguistic repertoires, including their home languages. Little attention has however been paid to the later years of primary school where the achievement gap between students with and without a migration background is particularly high. The present qualitative longitudinal study focusses on students in Years 4 and 5 and examines to what extent they deploy their linguistic repertoires in interaction with their peers. Drawing on observations, recordings and interviews, this paper explores the language use of two Portuguese-speaking 4th graders in Language and Arts lessons. Findings show that the students mobilize their linguistic and cultural resources to different extents and, hereby, open or close translingual discursive spaces for further exchange. The findings should contribute to the understanding of multilingual students’ language practices and provide insight into how their linguistic and cultural resources can be capitalized on. [less ▲]

Detailed reference viewed: 61 (7 UL)
Full Text
Peer Reviewed
See detailFunctional Interpretation of Single Amino Acid Substitutions in 1,330 Disease-Associated Genes
Iqbal, Sumaiya; Jespersen, Jakob Berg; Perez-Palma, Eduardo et al

in Biophysical Journal (2019, February 15), 116(3), 420-421

Elucidating molecular consequences of amino-acid-altering missense variants at scale is challenging. In this work, we explored whether features derived from three-dimensional (3D) protein structures can ... [more ▼]

Elucidating molecular consequences of amino-acid-altering missense variants at scale is challenging. In this work, we explored whether features derived from three-dimensional (3D) protein structures can characterize patient missense variants across different protein classes with similar molecular level activities. The identified disease-associated features can advance our understanding of how a single amino acid substitution can lead to the etiology of monogenic disorders. For 1,330 disease-associated genes (>80%, 1,077/1,330 implicated in Mendelian disorders), we collected missense variants from the general population (gnomAD database, N=164,915) and patients (ClinVar and HGMD databases, N=32,923). We in silico mapped the variant positions onto >14k human protein 3D structures. We annotated the protein positions of variants with 40 structural, physiochemical, and functional features. We then grouped the genes into 24 protein classes based on their molecular functions and performed statistical association analyses with the features of population and patient variants. We identified 18 (out of 40) features that are associated with patient variants in general. Specifically, patient variants are less exposed to solvent (p<1.0e-100), enriched on b-sheets (p<2.37e-39), frequently mutate aromatic residues (p<1.0e-100), occur in ligand binding sites (p<1.0e-100) and are spatially close to phosphorylation sites (p<1.0e-100). We also observed differential protein-class-specific features. For three protein classes (signaling molecules, proteases and hydrolases), patient variants significantly perturb the disulfide bonds (p<1.0e-100). Only in immunity proteins, patient variants are enriched in flexible coils (p<1.65e-06). Kinases and cell junction proteins exhibit enrichment of patient variants around SUMOylation (p<1.0e-100) and methylation sites (p<9.29e-11), respectively. In summary, we studied shared and unique features associated with patient variants on protein structure across 24 protein classes, providing novel mechanistic insights. We generated an online resource that contains amino-acid-wise feature annotation-track for 1,330 genes, summarizes the patient-variant-associated features on residue level, and can guide variant interpretation. [less ▲]

Detailed reference viewed: 95 (1 UL)
Full Text
Peer Reviewed
See detailHow to Assess the Usability Metrics of E-Voting Schemes
Marky, Karola; Zollinger, Marie-Laure UL; Funk, Markus et al

in Lecture Notes in Computer Science (2019, February)

Detailed reference viewed: 99 (10 UL)
Full Text
Peer Reviewed
See detailDismountable Flooring Systems for Multiple Use
Odenbreit, Christoph UL; Kozma, Andras UL

in IOP Conference Series: Earth and Environmental Science (2019, February), 225

Steel shapes our modern world as an integral part of the global construction economy. In the last decades, the sustainability of steel grew and turned from a linear to a circular business, where the ... [more ▼]

Steel shapes our modern world as an integral part of the global construction economy. In the last decades, the sustainability of steel grew and turned from a linear to a circular business, where the material is fully recovered and recycled after use. The RFCS Research Project “REDUCE” of the European Commission goes one step beyond the mere material recycling and investigates, how the circular economy’s philosophy can be used to reduce the carbon footprint furthermore. On that basis, one target of the research was to develop basic modular and standardised structural load bearing elements which can be adapted in the building or assembled, properly disassembled and partly or entirely be reused again in a subsequent building. This paper presents the respective research results of demountable flooring- and beam systems: 15 large scale push-out tests and two large scale composite beam tests as well as numerous finite element simulations with ABAQUS have been performed at the Laboratory of the ArcelorMittal Chair of Steel and Façade Engineering. The suitability for dis- and re-assembly as well as the strength, stiffness, slip capacity and ductility have been determined. The investigated systems included pre-stressed and epoxy injected systems, as well as solid slabs and composite slabs with profiled decking. The results showed sometimes higher resistances and smaller displacement capacities than conventional systems. The numerical simulation results were presented as well as the results of the laboratory tests. First assessments were given about the respective consequences and about how these consequences could be considered in the layout of future steel composite structures. [less ▲]

Detailed reference viewed: 7 (0 UL)
Full Text
Peer Reviewed
See detailSC2Share: Smart Contract for Secure Car Sharing
Akash, Madhusudan; Symeonidis, Iraklis UL; A. Mustafa, Mustafa et al

in International Conference on Information Systems Security and Privacy (ICISSP) (2019, January 24)

This paper presents an efficient solution for the booking and payments functionality of a car sharing system that allows individuals to share their personal, underused cars in a completely decentralized ... [more ▼]

This paper presents an efficient solution for the booking and payments functionality of a car sharing system that allows individuals to share their personal, underused cars in a completely decentralized manner, annulling the need of an intermediary. Our solution, named SC2Share, leverages smart contracts and uses them to carry out secure and private car booking and payments. Our experiments on SC2Share on the Ethereum testnet guarantee high security and privacy to its users and confirm that our system is cost-efficient and ready for practical use. [less ▲]

Detailed reference viewed: 243 (5 UL)
Full Text
Peer Reviewed
See detailNovel Opportunities by Laser Welding of Dissimilar Materials
Schiry, Marc UL; Plapper, Peter UL

in Proceedings of International Conference on Competitive Manufacturing COMA'19 (2019, January)

The Laser Technology Competence Centre (LTCC) of the University of Luxembourg provides skills in joining material combinations, which are considered being non-weld able with traditional methods or at ... [more ▼]

The Laser Technology Competence Centre (LTCC) of the University of Luxembourg provides skills in joining material combinations, which are considered being non-weld able with traditional methods or at least challenging to join (e.g. Copper and Aluminium, Aluminium and Polyamide (PA), Titanium and PEEK, steel and tungsten hard alloy). Related accomplishments include minimal intermetallic compounds, convincing mechanical and superior electrical properties of the laser-welded specimen. With defined spatial and temporal modulation of the laser beam, an accurately defined temperature profile is created on the lower side of the upper material in the two dimensional directions, which enable joining of dissimilar materials in overlap configurations, despite challenging thermal properties. To weld butt-joint geometries with minimal heat affected volume, the temperature profiles were expanded in the third dimension, which can be achieved through controlled laser energy guidance. The scientific methods to accomplish these convincing results are explained, with selected industrial use cases ranging from automotive industry, energy storage, and medical implants. An outlook with unsolved challenges is intended to ignite discussions about upcoming research topics. [less ▲]

Detailed reference viewed: 45 (6 UL)
Full Text
Peer Reviewed
See detailElucidation of influencing parameters of the laser butt welding process of dissimilar steel to tungsten alloy sheets
Schiry, Marc UL; Plapper, Peter UL

in Proceedings: International Conference on Competitive Manufacturing COMA'19 (2019, January)

Laser welding of steel - tungsten alloy joints requires deep understanding of the impact of the laser parameters on the welding process. Due to the dissimilar thermal and metallurgical properties of both ... [more ▼]

Laser welding of steel - tungsten alloy joints requires deep understanding of the impact of the laser parameters on the welding process. Due to the dissimilar thermal and metallurgical properties of both materials, a defined heat input and a precise temperature control in the weld interface is required. In the presented work, the influence of different laser parameter (e.g. laser power, focal position, scanner speed etc.) on the joint quality of laser welded steel / tungsten alloy butt-joints were investigated. By using statistical methods, the influencing process parameters were defined and optimized. It is shown that the horizontal focal position is the main parameter for the welding process in a butt-joint configuration. Additionally, manipulation of the heat input leads to modifications of the weld bead profile. By obtaining vertical seam boundaries in the sheet metal, a homogenous temperature profile at the interface of the materials to be welded was achieved. Due to the complete bonding and low amount of intermetallic phases, high shear strength accompanied with a low variance were the result. [less ▲]

Detailed reference viewed: 37 (4 UL)
Full Text
See detailMethodological Aspects of Software Engineering, Assurance, Quality, and Reliability Engineering (MAS/AQR) 2019 Welcome from the Minitrack Co-Chairs
Tenbergen, Bastian; Ries, Benoît UL

in Proceedings of the 52nd Hawaii International Conference on System Sciences (HICSS) (2019, January)

Detailed reference viewed: 39 (1 UL)
Full Text
Peer Reviewed
See detailEffects of acute yohimbine administration on interoception in major depression and childhood adversity
Kuehl, L. K.; Deuter, C. E.; Breden, I.-H. et al

in Psychoneuroendocrinology (2019), 107(Supplement 1), 4

Acute stress, release of stress hormones and chronic stress can affect the processing of visceral-afferent neural signals at different brain levels, which are important for interoception. However, it ... [more ▼]

Acute stress, release of stress hormones and chronic stress can affect the processing of visceral-afferent neural signals at different brain levels, which are important for interoception. However, it remains unclear if these effects are due to activation of the sympatho-adreno-medullary (SAM) axis or hypothalamicpituitary adrenocortical (HPA) axis. With this study, we aimed to investigate the selective effect of SAM axis activation on interoceptive accuracy. Central alpha2-adrenergic receptors represent a negative feedback mechanism of the SAM axis. For major depressive disorder (MDD) and adverse childhood experiences (ACE), alterations in the biological stress systems, including density and sensitivity of central alpha2-adrenergic receptors, have been shown. Healthy individuals without ACE (n = 46), healthy individuals with ACE (n = 23), patients with MDD and without ACE (n = 26) and patients with MDD with ACE (n = 22, all without antidepressant medication) were tested after oral administration of 10mg of yohimbine (alpha2-adrenergic receptors antagonist) and placebo administration in a repeated measures design. Interoceptive accuracy and sensibility were assessed in a heartbeat tracking task. Increases in systolic and diastolic blood pressure after yohimbine administration in all groups confirmed successful activation of the SAM axis. Interoceptive accuracy decreased after yohimbine intake only in the healthy group with ACE, but remained unchanged in all other groups. This ‘group’בdrug’ interaction effect may be due to selective up-regulation of alpha2- adrenergic receptors after experience of childhood trauma, which reduces capacity for attention focus on heartbeats. Suppressed processing of physical sensations in stressful situations may represent an adaptive response in healthy individuals with childhood adversity. [less ▲]

Detailed reference viewed: 14 (0 UL)
Full Text
Peer Reviewed
See detailAccess Time Improvement Framework for Standardized IoT Gateways
Javed, Asad; Yousefnezhad, Narges; Robert, Jérémy UL et al

in Proceedings of IEEE International Conference on Pervasive Computing and Communications (2019)

Detailed reference viewed: 17 (1 UL)
Full Text
See detailReductions of elliptic curves
Perucca, Antonella UL

in Proceedings of the Roman Number Theory Association (2019), 4

Detailed reference viewed: 78 (7 UL)
Full Text
Peer Reviewed
See detailMaximum flow of complex manufacturing networks
Omar, Yamila UL; Plapper, Peter UL

in Procedia CIRP (2019)

Detailed reference viewed: 31 (1 UL)
Full Text
Peer Reviewed
See detailJSSJ Meets RELOCAL – Mobilizations, Meaning and Uses of the Concept of Spatial Justice in a European Research Project
Blondel, Cyril UL; Evrard, Estelle UL; Németh, Sarolta et al

in Justice Spatiale - Spatial Justice (2019), 13

Detailed reference viewed: 26 (0 UL)
Full Text
Peer Reviewed
See detailFabrication and Optical Characterization of Hyperbolic Nanoparticles on a Transparent Substrate
Iarossi, Marzia; Darvill, Daniel; Isoniemi, Tommi et al

in Proceedings of SPIE : The International Society for Optical Engineering (2019), 10927

We report on the fabrication and optical characterization of hyperbolic nanoparticles on a transparent substrate. These nanoparticles enable a separation of ohmic and radiative channels in the visible and ... [more ▼]

We report on the fabrication and optical characterization of hyperbolic nanoparticles on a transparent substrate. These nanoparticles enable a separation of ohmic and radiative channels in the visible and near-infrared frequency ranges. The presented architecture opens the pathway towards novel routes to exploit the light to energy conversion channels beyond what is offered by current plasmon-based nanostructures, possibly enabling applications spanning from thermal emission manipulation, theragnostic nano-devices, optical trapping and nano-manipulation, non-linear optical properties, plasmonenhanced molecular spectroscopy, photovoltaics and solar-water treatments, as well as heat-assisted ultra-dense and ultrafast magnetic recording. [less ▲]

Detailed reference viewed: 79 (1 UL)
Full Text
Peer Reviewed
See detailPrivacy and Linkability of Mining in Zcash
Biryukov, Alex UL; Feher, Daniel UL

in Proceedings of 2019 IEEE Conference on Communications and Network Security (2019)

With the growth in popularity for cryptocurrencies the need for privacy preserving blockchains is growing as well. Zcash is such a blockchain, providing transaction privacy through zero-knowledge proofs ... [more ▼]

With the growth in popularity for cryptocurrencies the need for privacy preserving blockchains is growing as well. Zcash is such a blockchain, providing transaction privacy through zero-knowledge proofs. In this paper we analyze transaction linkability in Zcash based on the currency minting transactions (mining). Using predictable usage patterns and clustering heuristics on mining transactions an attacker can link to publicly visible addresses over 84% of the volume of the transactions that use a ZK-proof. Since majority of Zcash transactions are not yet using ZK-proofs, we show that overall 95.5% of the total number of Zcash transactions are potentially linkable to public addresses by just observing the mining activity. [less ▲]

Detailed reference viewed: 107 (17 UL)
Full Text
Peer Reviewed
See detailJSSJ rencontre RELOCAL – Mobilisations, sens et usages du concept de justice spatiale dans un projet de recherche européen
Blondel, Cyril UL; Evrard, Estelle UL; Németh, Sarolta et al

in Justice Spatiale - Spatial Justice (2019), 13(Espace public), 1-13

Detailed reference viewed: 27 (0 UL)
Full Text
Peer Reviewed
See detailDeanonymization and linkability of cryptocurrency transactions based on network analysis
Biryukov, Alex UL; Tikhomirov, Sergei UL

in Proceedings of 2019 IEEE European Symposium on Security and Privacy (EuroS&P) (2019)

Bitcoin, introduced in 2008 and launched in 2009, is the first digital currency to solve the double spending problem without relying on a trusted third party. Bitcoin provides a way to transact without ... [more ▼]

Bitcoin, introduced in 2008 and launched in 2009, is the first digital currency to solve the double spending problem without relying on a trusted third party. Bitcoin provides a way to transact without any trusted intermediary, but its privacy guarantees are questionable. Despite the fact that Bitcoin addresses are not linked to any identity, multiple deanonymization attacks have been proposed. Alternative cryptocurrencies such as Dash, Monero, and Zcash aim to provide stronger privacy by using sophisticated cryptographic techniques to obfuscate transaction data. Previous work in cryptocurrency privacy mostly focused on applying data mining algorithms to the transaction graph extracted from the blockchain. We focus on a less well researched vector for privacy attacks: network analysis. We argue that timings of transaction messages leak information about their origin, which can be exploited by a well connected adversarial node. For the first time, network level attacks on Bitcoin and the three major privacy-focused cryptocurrencies have been examined. We describe the message propagation mechanics and privacy guarantees in Bitcoin, Dash, Monero, and Zcash. We propose a novel technique for linking transactions based on transaction propagation analysis. We also unpack address advertisement messages (ADDR), which under certain assumptions may help in linking transaction clusters to IP addresses of nodes. We implement and evaluate our method, deanonymizing our own transactions in Bitcoin and Zcash with a high level of accuracy. We also show that our technique is applicable to Dash and Monero. We estimate the cost of a full-scale attack on the Bitcoin mainnet at hundreds of US dollars, feasible even for a low budget adversary. [less ▲]

Detailed reference viewed: 473 (21 UL)
Full Text
Peer Reviewed
See detailPortrait of a Miner in a Landscape
Biryukov, Alex UL; Feher, Daniel UL

in IEEE INFOCOM 2019 Workshop Proceedings (2019)

Mining is one of the core elements of the proof-of-work based cryptocurrency economy. In this paper we investigate the generic landscape and hierarchy of miners on the example of Ethereum and Zcash, two ... [more ▼]

Mining is one of the core elements of the proof-of-work based cryptocurrency economy. In this paper we investigate the generic landscape and hierarchy of miners on the example of Ethereum and Zcash, two blockchains that are among the top 5 in terms of USD value of created coins. Both chains used ASIC resistant proofs-of-work which favors GPU mining in order to keep mining decentralized. This however has changed with recent introduction of ASIC miners for these chains. This transition allows us to develop methods that might detect hidden ASIC mining in a chain (if it exists), and to study how the introduction of ASICs effects the decentralization of mining power. Finally, we describe how an attacker might use public blockchain information to invalidate the privacy of miners, deducing the mining hardware of individual miners and their mining rewards. [less ▲]

Detailed reference viewed: 74 (9 UL)
Full Text
Peer Reviewed
See detailFRET Characterization of Hollow Plasmonic Nanoantennas
Maccaferri, Nicolò UL; Ponzellini, Paolo; Giovannini, Giorgia et al

in Proceedings of SPIE : The International Society for Optical Engineering (2019), 10894

We fabricated hollow nanoantennas with varying inner channels sizes on a gold-covered silicon nitride membrane. Our fabrication technique allowed us to narrow the size of the inner channels down to 15nm ... [more ▼]

We fabricated hollow nanoantennas with varying inner channels sizes on a gold-covered silicon nitride membrane. Our fabrication technique allowed us to narrow the size of the inner channels down to 15nm. We managed to exclusively decorate the tips of the antennas with thiol-conjugated dyes by creating a concentration gradient through the nanoantennas. Finally, we characterized the antennas in terms of their effect on the lifetime of dyes. We used Atto 520 and Atto 590 for the experiments. We carried out experiments with the antennas decorated with Atto 520, with Atto 590 as well as with the two Atto dyes at the same time. The experiments carried out with the antennas decorated with Atto 520 only and Atto 590 only yielded a lifetime reduction with respect to the confocal case. Interestingly, their lifetime reductions were significantly different. Then, we decorated the antennas with the two dyes at the same time. Even though we could not control the distance between the two dyes, FRET effects were clearly observed. The FRET effects were found to be dependent on the size of the inner channel. We believe that our tip decorated hollow nanoantennas could find application in FRET-based single molecule nanopore technologies. [less ▲]

Detailed reference viewed: 58 (0 UL)
Full Text
Peer Reviewed
See detailRobotic trajectory tracking: Bio-inspired position and torque control
Klecker, Sophie UL; Hichri, Bassem UL; Plapper, Peter UL

in Procedia CIRP (2019)

As far as complex contact-based manufacturing tasks are concerned, humans outperform machines. Indeed, conventionally controlled robotic manipulators are limited to basic applications in close to ideal ... [more ▼]

As far as complex contact-based manufacturing tasks are concerned, humans outperform machines. Indeed, conventionally controlled robotic manipulators are limited to basic applications in close to ideal circumstances. However, tedious work in hazardous environments, make some tasks unsuitable for humans. Therefore, the interest in expanding the application-areas of robots arose. This paper employs a bottom-up approach to develop robust and adaptive learning algorithms for trajectory tracking: position and torque control in the presence of uncertainties and switching constraints. The robotic manipulators mimicking the human behavior based on bio-inspired algorithms, take advantage of their know-how. Simulations and experiments validate the concept-performance. [less ▲]

Detailed reference viewed: 17 (0 UL)
Full Text
Peer Reviewed
See detailInteroception in Bulimia Nervosa: Evidence at cortical and self-report levels
Lutz, Annika UL; Van Dyck, Zoé UL; Schulz, André UL et al

in Psychophysiology (2019), 56(S1), 117

Bulimia nervosa (BN) is characterized by recurrent episodes of binge eating and compensatory behaviors, such as self- induced vomiting. Body image disturbance is also prominent in BN. Current research is ... [more ▼]

Bulimia nervosa (BN) is characterized by recurrent episodes of binge eating and compensatory behaviors, such as self- induced vomiting. Body image disturbance is also prominent in BN. Current research is trying to determine which dimensions and sensory domains of body perception are affected in BN. Regarding heartbeat perception, findings are inconclusive, with some studies reporting reduced and others reporting unaltered interoceptive accuracy in BN. The current study contributes further data on heartbeat perception by using an indicator of the cortical processing of cardio- afferent signals (heartbeat evoked potentials, HEPs). We investigated 22 women with current or partially remitted BN (BMI 23.94[3.61]; age 31.86[11.20]) and 22 healthy women (HC; BMI 24.24[3.37]; age 31.00[10.15]). Participants performed a heartbeat perception task (according to Schandry) with concurrent 64- channel- EEG and ECG recording. HEPs were calculated as mean EEG amplitudes in the interval 455- 595ms after the R- peak of the ECG. Results show no significant differences between the BN and HC groups, neither for heartbeat perception, HEPs, or mean heartrate. These results confirm previous findings of intact heartbeat perception in BN. In addition, cortical processing of cardio- afferent signals is unaltered. Heartbeat perception is particularly relevant for emotion processing and regulation. The previously reported emotion- regulation deficits in BN appear not to be based on altered CNS processing of cardiac signals [less ▲]

Detailed reference viewed: 14 (4 UL)
Full Text
Peer Reviewed
See detailOn the Evolution of Mobile App Complexity
Gao, Jun UL; Li, ; Bissyande, Tegawendé François D Assise UL et al

in Proceedings of 2019 24th International Conference on Engineering of Complex Computer Systems (2019)

Android developers are known to frequently update their apps for fixing bugs and addressing vulnerabilities, but more commonly for introducing new features. This process leads a trail in the ecosystem ... [more ▼]

Android developers are known to frequently update their apps for fixing bugs and addressing vulnerabilities, but more commonly for introducing new features. This process leads a trail in the ecosystem with multiple successive app versions which record historical evolutions of a variety of apps. While the literature includes various works related to such evolutions, little attention has been paid to the research question on how quality evolves, in particular with regards to maintainability and code complexity. In this work, we fill this gap by presenting a largescale empirical study: we leverage the AndroZoo dataset to obtain a significant number of app lineages (i.e., successive releases of the same Android apps), and rely on six well-established, maintainability-related complexity metrics commonly accepted in the literature on app quality, maintainability etc. Our empirical investigation eventually reveals that, overall, while Android apps become bigger in terms of code size as time goes by, the apps themselves appear to be increasingly maintainable and thus decreasingly complex [less ▲]

Detailed reference viewed: 12 (1 UL)
Full Text
Peer Reviewed
See detailPlasmonic Nanopore Prepared on MoS2 Membrane - Hybrid Nanostructures Based on Site Selective Deposition
Mosconi, Dario; Miele, Ermanno; Giovannini, Giovannini et al

in Proceedings of SPIE : The International Society for Optical Engineering (2019), 10894

Here, we propose easy and robust strategies for the versatile integration 2D material flakes on plasmonic nanoholes by means of site selective deposition of MoS2. The methods can be applied both to simple ... [more ▼]

Here, we propose easy and robust strategies for the versatile integration 2D material flakes on plasmonic nanoholes by means of site selective deposition of MoS2. The methods can be applied both to simple metallic flat nanostructures and to complex 3D metallic structures comprising nanoholes. The deposition methods allow the decoration of large ordered arrays of plasmonic structures with single or few layers of MoS2. We show that the plasmonic field generated by the nanohole can interact significantly with the 2D layer, thus representing an ideal system for hybrid 2DMaterial/ Plasmonic investigation. The controlled/ordered integration of 2D materials on plasmonic nanostructures opens a pathway towards new investigation of the following: enhanced light emission; strong coupling from plasmonic hybrid structures; hot electron generation; and sensors in general based on 2D materials. [less ▲]

Detailed reference viewed: 67 (0 UL)
Full Text
Peer Reviewed
See detailScalable Gaussian Process Inference with Finite-data Mean and Variance Guarantees
Huggins, Jonathan; Campbell, Trevor; Kasprzak, Mikolaj UL et al

in Proceedings of the 22nd International Conference on Artificial Intelligence and Statistics (AISTATS) 2019 (2019)

Detailed reference viewed: 17 (2 UL)
Full Text
Peer Reviewed
See detailL'action extérieure de l'Union européenne à la lumière du Brexit
Neframi, Eleftheria UL

in ERPL/PEDP (2019), 31(1), 209-239

The withdrawal of the UK from the Union places the exiting Member State within the framework of the exernal action of the Union. The present contribution studies the two dimensions of the impact of Brexit ... [more ▼]

The withdrawal of the UK from the Union places the exiting Member State within the framework of the exernal action of the Union. The present contribution studies the two dimensions of the impact of Brexit on the external action of the European Union: on the one hand, in the relationships between the UK-third country and the EU; on the other hand, in the relationships between the EU and the third countries and in particular in what concerns the change in treaty relations. The principles that govern the Union’s external action are adapted to the specific process and to the unprecedented context of Brexit, without losing sight of the Union’s objective of affirming itself as an international credible player. A new dynamic of the external action of the Union could emerge from the opportunity that Brexit offers to reconsider the status of Member State and the Union’s objectives. [less ▲]

Detailed reference viewed: 45 (0 UL)
Full Text
Peer Reviewed
See detailUsing data from the HBSC study for evidence-based suicide prevention in Luxembourg
van Duin, Claire UL; Heinz, Andreas UL; Catunda, Carolina UL et al

in European Journal of Public Health (2019), 29

Detailed reference viewed: 25 (1 UL)
Full Text
Peer Reviewed
See detailTransaction Clustering Using Network Traffic Analysis for Bitcoin and Derived Blockchains
Biryukov, Alex UL; Tikhomirov, Sergei UL

in IEEE INFOCOM 2019 Workshop Proceedings (2019)

Bitcoin is a decentralized digital currency introduced in 2008 and launched in 2009. Bitcoin provides a way to transact without any trusted intermediary, but its privacy guarantees are questionable, and ... [more ▼]

Bitcoin is a decentralized digital currency introduced in 2008 and launched in 2009. Bitcoin provides a way to transact without any trusted intermediary, but its privacy guarantees are questionable, and multiple deanonymization attacks have been proposed. Cryptocurrency privacy research has been mostly focused on blockchain analysis, i.e., extracting information from the transaction graph. We focus on another vector for privacy attacks: network analysis. We describe the message propagation mechanics in Bitcoin and propose a novel technique for transaction clustering based on network traffic analysis. We show that timings of transaction messages leak information about their origin, which can be exploited by a well connected adversarial node. We implement and evaluate our method in the Bitcoin testnet with a high level of accuracy, deanonymizing our own transactions issued from a desktop wallet (Bitcoin Core) and from a mobile (Mycelium) wallet. Compared to existing approaches, we leverage the propagation information from multiple peers, which allows us to overcome an anti-deanonymization technique (“diffusion”) used in Bitcoin. [less ▲]

Detailed reference viewed: 112 (5 UL)
Full Text
Peer Reviewed
See detailBlockchain-based Micropayment Systems: Economic Impact
Khan, Nida UL; Ahmad, Tabrez; State, Radu UL

in ACM IDEAS '19 Proceedings of the 23rd International Database Engineering & Applications Symposium (2019)

The inception of blockchain catapulted the development of innovative use cases utilizing the trustless, decentralized environment, empowered by cryptocurrencies. The envisaged benefits of the technology ... [more ▼]

The inception of blockchain catapulted the development of innovative use cases utilizing the trustless, decentralized environment, empowered by cryptocurrencies. The envisaged benefits of the technology includes the divisible nature of a cryptocurrency, that can facilitate payments in fractions of a cent, enabling micropayments through the blockchain. Micropayments are a critical tool to enable financial inclusion and to aid in global poverty alleviation. The paper conducts a study on the economic impact of blockchain-based micropayment systems, emphasizing their significance for socioeconomic benefit and financial inclusion. The paper also highlights the contribution of blockchain-based micropayments to the cybercrime economy, indicating the critical need of economic regulations to curtail the growing threat posed by the digital payment mechanism. [less ▲]

Detailed reference viewed: 133 (12 UL)
Full Text
Peer Reviewed
See detailRigor or rhetoric: Public philosopher and public in dialogue
Burks, Deven UL

in Perspectives: international postgraduate journal of philosophy (2019), 9(1), 1-10

Brian Leiter (2016) throws down two gauntlets to philosophers engaged in dialogue with the broader public. If, with the first, public philosophers recognize that they cannot offer substantive answers but ... [more ▼]

Brian Leiter (2016) throws down two gauntlets to philosophers engaged in dialogue with the broader public. If, with the first, public philosophers recognize that they cannot offer substantive answers but only sophisticated method, they nevertheless fail to realize that said method does not resonate with the very public whom they purport to help. For, with the second, that method does not engage the emotivist and tribalist cast of contemporary public discourse: emotivist because a person’s moral and political beliefs are a function of emotional attitudes or affective responses for which she adduces reasons post hoc; tribalist because the person tracks not the inferential relation between beliefs but her similarity with interlocutors. In order to understand the full extent of this critique, it is necessary, first, to parse strands of public philosophy, distinct discursive sites, and pictures of philosophical practice and, then, to probe the critique’s empirical groundedness and intended scope. These elements in place, it is then possible to sketch public philosophy reconceived along Leiter’s lines as equal part rigor and rhetoric. That sketch may be somewhat filled out through two tactics employed in Jeffrey Stout’s (2004, 2010) work. These form part of a toolkit for philosophical dialogue whereby philosophers get a discursive grip on non-discursive factors underlying public discourse and push back on Leiter's dilemma. [less ▲]

Detailed reference viewed: 54 (1 UL)
Full Text
Peer Reviewed
See detailRule-Based Supervisory Control-Extension for Automated Manufacturing Processes
Klecker, Sophie UL; Hichri, Bassem UL; Plapper, Peter UL

in International Journal of Mechanical Engineering and Robotics Research (2019)

Before performing a surface finishing process, human operators analyze the workpiece-conditions and react accordingly, i.e. they adapt the contact-situation of the tool with respect to the surface. This ... [more ▼]

Before performing a surface finishing process, human operators analyze the workpiece-conditions and react accordingly, i.e. they adapt the contact-situation of the tool with respect to the surface. This first step is ignored in most suggested automation concepts. Although their performance is satisfactory for the general process thanks to adaptive position- and force-/torque-control algorithms, they are unable to address specific problematic cases as often encountered in practice because of variations in workpiece-dimensions or -positioning. In this work, a human mimicking element is developed to overcome this limitation of current control concepts and to translate human expertise to the robotic manipulator. A rule-based system is designed where human knowledge is encoded as if-then rules. This system is integrated with a previously suggested control strategy in a hierarchical manner. The developed concept is experimentally validated on a KUKA LWR 4+-robotic manipulator. [less ▲]

Detailed reference viewed: 71 (10 UL)
Full Text
See detailConcrete-Filled Steel Tubular (CFTS) Columns Subjected to Eccentric Compressive Load
KEDZIORA, SLAWOMIR UL; Anwaar, Muhammad Omer

in AIP Conference Proceedings (2018, November 15)

Concrete-steel composite structures are very efficient in carrying high loads as they combine benefits of both materials concrete and steel. The combination of them can significantly improve the strength ... [more ▼]

Concrete-steel composite structures are very efficient in carrying high loads as they combine benefits of both materials concrete and steel. The combination of them can significantly improve the strength of the composite structure by taking advantage of high compression resistance of concrete and high strength of steel in tension. Recently, there has been renewed interest in the composite structures used in different forms, as beams, slabs, sandwich structures and columns and many methods of structural analyses were utilised. However, none of them was able to eliminate concrete material when it fractured. The presented work concerns circular composite columns CFST under eccentric compression. The principal objective of the project was to investigate a straightforward method based on a finite element analysis employed to estimate the load carrying capacity of columns. This study has also been set out to determine whether the Drucker-Prager material model of concrete without a crack capability could be used for analyses of the CFST columns with the additional elimination of the concrete material when concrete is damaged. The elaborated finite element model was verified with existing test data from the literature. The findings show that the correlation between the test results and the numerical analysis was excellent confirming the feasibility of usage of the proposed method for the assessment of complex cases of the CFST columns. A new part of the work is the employment of a death element feature to eliminate concrete material, which theoretically is not taking any load after reaching its tensile strength. A criterion to eliminate elements from the model is the maximum principal stress greater than tensile strength. The obtained results are excellent; the established goal was met entirely. [less ▲]

Detailed reference viewed: 113 (23 UL)
Full Text
Peer Reviewed
See detailFAST: A MapReduce Consensus for High Performance Blockchains
Khan, Nida UL

in ACM BlockSys'18 Proceedings of the 1st Workshop on Blockchain-enabled Networked Sensor Systems (2018, November 04)

Blockchain platforms when used as a database for IoT systems can resolve data reliability fault-tolerance, consistency and non-repudiation issues. However, their inherent shortcomings related to their ... [more ▼]

Blockchain platforms when used as a database for IoT systems can resolve data reliability fault-tolerance, consistency and non-repudiation issues. However, their inherent shortcomings related to their throughput in terms of processed transactions, limit their applicability in such environments in a decentralized way as the underlying network is unable to sustain high workloads. In this paper a fully decentralized high performance consensus mechanism, named FAST, is proposed for a public blockchain. FAST is based on mapreduce paradigm for aggregating and adding transactions on blockchain blocks. FAST was implemented and evaluated in a basic blockchain prototype. A light client for FAST using IPFS, was developed to bring about a reduction in the data stored locally. The obtained results from tests conducted on the prototype depict that FAST exceeds the performance of not just other existing blockchain platforms but comes very close to the throughput of traditional electronic payment networks such as Visa. [less ▲]

Detailed reference viewed: 80 (17 UL)
Full Text
See detailA survey: The usage of Augmented Reality in Industry
Gallala, Abir UL; Hichri, Bassem UL; Plapper, Peter UL

in Robotix-Academy Conference for Industrial Robotics 2018 (2018, November 01)

Human-Robot-Interaction technologies in industry 4.0 and modern manufacturing are more and more growing. Using off-line robot programming methods such as Augmented Reality (AR) could gain time and money ... [more ▼]

Human-Robot-Interaction technologies in industry 4.0 and modern manufacturing are more and more growing. Using off-line robot programming methods such as Augmented Reality (AR) could gain time and money as well as improve programming and repair tasks. This paper is a study of the use of AR in smart factories. [less ▲]

Detailed reference viewed: 61 (9 UL)
Full Text
Peer Reviewed
See detailDeterminants of cognitive decline in a large cross-national study using machine learning
Leist, Anja UL

in Innovation in Aging (2018, November), 2(S1), 244

Detailed reference viewed: 118 (9 UL)
Full Text
Peer Reviewed
See detailReflecting on teachers' practices as multimodally co-constructed in spatial reality
Arend, Béatrice UL

in Proceedings of ICERI2018 (2018, November)

Detailed reference viewed: 45 (7 UL)
Full Text
Peer Reviewed
See detailAssociations of wealth with frailty and memory impairment across the course of aging
Leist, Anja UL

in Innovation in Aging (2018, November), 2(S1), 906

Detailed reference viewed: 44 (1 UL)
Full Text
Peer Reviewed
See detailAre mutants really natural? A study on how “naturalness” helps mutant selection
Jimenez, Matthieu UL; Titcheu Chekam, Thierry UL; Cordy, Maxime UL et al

in Proceedings of 12th International Symposium on 
 Empirical Software Engineering and Measurement (ESEM'18) (2018, October 11)

Background: Code is repetitive and predictable in a way that is similar to the natural language. This means that code is ``natural'' and this ``naturalness'' can be captured by natural language modelling ... [more ▼]

Background: Code is repetitive and predictable in a way that is similar to the natural language. This means that code is ``natural'' and this ``naturalness'' can be captured by natural language modelling techniques. Such models promise to capture the program semantics and identify source code parts that `smell', i.e., they are strange, badly written and are generally error-prone (likely to be defective). Aims: We investigate the use of natural language modelling techniques in mutation testing (a testing technique that uses artificial faults). We thus, seek to identify how well artificial faults simulate real ones and ultimately understand how natural the artificial faults can be. %We investigate this question in a fault revelation perspective. Our intuition is that natural mutants, i.e., mutants that are predictable (follow the implicit coding norms of developers), are semantically useful and generally valuable (to testers). We also expect that mutants located on unnatural code locations (which are generally linked with error-proneness) to be of higher value than those located on natural code locations. Method: Based on this idea, we propose mutant selection strategies that rank mutants according to a) their naturalness (naturalness of the mutated code), b) the naturalness of their locations (naturalness of the original program statements) and c) their impact on the naturalness of the code that they apply to (naturalness differences between original and mutated statements). We empirically evaluate these issues on a benchmark set of 5 open-source projects, involving more than 100k mutants and 230 real faults. Based on the fault set we estimate the utility (i.e. capability to reveal faults) of mutants selected on the basis of their naturalness, and compare it against the utility of randomly selected mutants. Results: Our analysis shows that there is no link between naturalness and the fault revelation utility of mutants. We also demonstrate that the naturalness-based mutant selection performs similar (slightly worse) to the random mutant selection. Conclusions: Our findings are negative but we consider them interesting as they confute a strong intuition, i.e., fault revelation is independent of the mutants' naturalness. [less ▲]

Detailed reference viewed: 98 (13 UL)
Full Text
Peer Reviewed
See detailThe Levodopa Response Trial and the Parkinson Disease Digital Biomarker Challenge: Monitoring symptoms of Parkinson’s disease in the lab and home using wearable sensors
Daneault, J.; Vergara-Diaz, G.; Costante, G. et al

in Movement Disorders : Official Journal of the Movement Disorder Society (2018, October 03), 33(S2), 525

Objective: To leverage a community of researchers and shared wearable data to develop algorithms to estimate the severity of PD specific symptoms. Background: People with Parkinson’s disease (PwPD) often ... [more ▼]

Objective: To leverage a community of researchers and shared wearable data to develop algorithms to estimate the severity of PD specific symptoms. Background: People with Parkinson’s disease (PwPD) often experience fluctuations in motor symptom severity. Wearable sensors have the potential to help clinicians monitor symptoms over time, outside the clinic. However, to gather accurate and clinically-relevant measures, there is a need to develop robust algorithms based on clinically- labelled data. Methods: The Levodopa Response Trial captured three-axis acceleration from two wrist-worn sensors and a smartphone located at the waist from 29 PwPD continuously over 4 days. On day 1, in an in-clinic visit, participants performed clinical assessments and motor tasks on their regular medication regimen. During these visits, a clinician also provided symptom severity scores for tremor, bradykinesia, and dyskinesia. On days 2 & 3, sensor data was collected while participants were at home. On day 4, participants returned to the clinic for the same assessments as day 1, but arrived without having taken their medication for at least 10 hours. Leveraging this dataset, Sage Bionetworks, the Michael J Fox Foundation and the Robert Wood Johnson Foundation launched the PD Digital Biomarker DREAM Challenge which made a subset of the data available to researchers to develop robust and accurate algorithms for the estimation of specific symptoms’ severity. Results: Teams participating in the challenge used several technical approaches, from signal processing to deep learning. 35 submissions were received for the estimation of action tremor severity. Teams achieved an area under the precision-recall curve (AUPR) of 0.444 to 0.75. As for dyskinesia during movement, 37 submissions were received and the teams achieved an AUPR of 0.175 to 0.477. Finally, 39 submissions were received for the estimation of bradykinesia and the teams achieved an AUPR of 0.413 to 0.95. Null expectations for the testing datasets were 0.432, 0.195, and 0.266, respectively. Conclusions: Making datasets available to the community leverages the creativity of different groups to develop robust and accurate algorithms for the estimation of PD symptom severity. This will lead to better quality and interpretability of data collected in unsupervised settings within the community. [less ▲]

Detailed reference viewed: 167 (7 UL)
Full Text
Peer Reviewed
See detailA17044 Community health workers for non-communicable disease interventions in the digital age
Mishra, Shiva Raj; Lygidakis, Charilaos UL; Neupane, Dinesh et al

in Journal of Hypertension (2018, October)

Objectives: In this study, we review the evidence and discuss how the digitalization affects the CHWs programs for tackling non-communicable diseases (NCDs) in low-and-middle income countries (LMICs ... [more ▼]

Objectives: In this study, we review the evidence and discuss how the digitalization affects the CHWs programs for tackling non-communicable diseases (NCDs) in low-and-middle income countries (LMICs). Methods: We conducted a review of literature covering two databases: PubMED and Embase. A total of 97 articles were abstracted for full text review of which 21 are included in the analysis. Existing theories were used to construct a conceptual framework for understanding how digitalization affects the prospects of CHW programs for NCDs. Results: We identified three benefits and three challenges of digitalization. Firstly, it will help improve the access and quality of services, notwithstanding its higher establishment and maintenance costs. Secondly, it will add efficiency in training and personnel management. Thirdly, it will leverage the use of data generated across grass-roots platforms to further research and evaluation. The challenges posed are related to funding, health literacy of CHWs, and systemic challenges related to motivating CHWs. More than 60 digital platforms were identified, including mobile based networking devices (used for behavioral change communication), Web-applications (used for contact tracking, reminder system, adherence tracing, data collection, and decision support), videoconference (used for decision support) and mobile applications (used for reminder system, supervision, patients’ management, hearing screening, and tele-consultation). Conclusion: The digitalization efforts of CHW programs are afflicted by many challenges, yet the rapid technological penetration and acceptability coupled with the gradual fall in costs constitute encouraging signals for the LMICs. Both CHWs interventions and digital technologies are not inexpensive, but they may provide better value for the money. [less ▲]

Detailed reference viewed: 87 (0 UL)
Full Text
Peer Reviewed
See detailA Contribution to Cyber-Physical Systems Security: an Event-based Attack-tolerant Control Approach
Bezzaoucha, Souad UL; Voos, Holger UL

in Proceedings of 10th IFAC Symposium on Fault Detection, Supervision and Safety for Technical Processes, SAFEPROCESS 2018 (2018, August 29)

In the present paper, a model-based fault/attack tolerant scheme is proposed to deal with cyber-threats on Cyber Physicals Systems. A common scheme based on observers is designed and a state feedback ... [more ▼]

In the present paper, a model-based fault/attack tolerant scheme is proposed to deal with cyber-threats on Cyber Physicals Systems. A common scheme based on observers is designed and a state feedback control based on an event-triggered framework is given with control synthesis and condition on the switching time. An event-based implementation is proposed in order to achieve novel security strategy. Observer and controller gains are deduced by solving su cient Bilinear Matrix Inequality (BMI) condition. Simulation results on a real-time laboratory three tank system are given to show the attack-tolerant control ability despite data deception attacks on both actuators and sensors. [less ▲]

Detailed reference viewed: 165 (22 UL)
Full Text
Peer Reviewed
See detailVisual emulation for Ethereum's virtual machine
Norvill, Robert UL; Fiz Pontiveros, Beltran UL; State, Radu UL et al

in NOMS 2018 - 2018 IEEE/IFIP Network Operations and Management Symposium (2018, July 09)

In this work we present E-EVM, a tool that emulates and visualises the execution of smart contracts on the Ethereum Virtual Machine. By working with the readily available bytecode of smart contracts we ... [more ▼]

In this work we present E-EVM, a tool that emulates and visualises the execution of smart contracts on the Ethereum Virtual Machine. By working with the readily available bytecode of smart contracts we are able to display the program's control flow graph, opcodes and stack for each step of contract execution. This tool is designed to aid the user's understanding of the Etheruem Virtual Machine as well as aid the analysis of any given smart contract. As such, it functions as both an analysis and a learning tool. It allows the user to view the code in each block of a smart contract and follow possible control flow branches. It is able to detect loops and suggest optimisation candidates. It is possible to step through a contract one opcode at a time. E-EVM achieved an average of 85.6% code coverage when tested. [less ▲]

Detailed reference viewed: 55 (4 UL)
Full Text
Peer Reviewed
See detailAssessing the performance of coordinated predictive control strategies on urban-motorway networks
Rinaldi, Marco UL; Viti, Francesco UL

in IFAC-PapersOnLine (2018, July), 51(9), 285-290

Coordination and integration of different traffic control policies have been of considerable interest in research in the last decades and, recently, have been object of large scale implementation trials ... [more ▼]

Coordination and integration of different traffic control policies have been of considerable interest in research in the last decades and, recently, have been object of large scale implementation trials. In the setting of peri-urban motorway systems, coordination of various kinds of controllers must however be accompanied by accurate prediction of both propagation of flows and queues in the network, as well as the users’ response in terms of route choice. In this paper, we showcase through a real-life case study how coordination and prediction are both essential when performing hybrid urban-motorway control. Simulation results of a Model Predictive Control application are compared to simpler local control approaches, and the impact of coordinated intersection control and, additionally, Ramp Metering is evaluated. [less ▲]

Detailed reference viewed: 48 (1 UL)
Full Text
Peer Reviewed
See detailA Decoupling Approach to Design Observers for Polytopic Takagi-Sugeno Models Subject to Unknown Inputs
Bezzaoucha, Souad UL; Voos, Holger UL; Davila, Jorge et al

in Proceedings of the 2018 American Control Conference (2018, June 27)

A decoupling approach for state estimation of nonlinear systems represented in the polytopic Takagi-Sugeno with unmeasurable premise variables subject to unknown inputs is proposed in this paper. The idea ... [more ▼]

A decoupling approach for state estimation of nonlinear systems represented in the polytopic Takagi-Sugeno with unmeasurable premise variables subject to unknown inputs is proposed in this paper. The idea consists in defining a state and unknown input transformations in order to divide the state vector into two parts, a measurable part and an observable one (decoupled from the unknown input). A classical Luenberger observer to estimate the unmeasurable part is then designed and given in terms of Linear Matrix Inequalities (LMIs) conditions. A numerical example is also presented in order to illustrate the proposed approach. [less ▲]

Detailed reference viewed: 121 (6 UL)
Full Text
Peer Reviewed
See detailCyber Security and Vulnerability Analysis of Networked Control System subject to False-Data injection
Gerard, Benjamin; Bezzaoucha, Souad UL; Voos, Holger UL et al

in Proceedings of the 2018 American Control Conference (2018, June 27)

In the present paper, the problem of networked control system (NCS) cyber security is considered. The geometric approach is used to evaluate the security and vulnerability level of the controlled system ... [more ▼]

In the present paper, the problem of networked control system (NCS) cyber security is considered. The geometric approach is used to evaluate the security and vulnerability level of the controlled system. The proposed results are about the so-called false data injection attacks and show how imperfectly known disturbances can be used to perform undetectable, or at least stealthy, attacks that can make the NCS vulnerable to attacks from malicious outsiders. A numerical example is given to illustrate the approach. [less ▲]

Detailed reference viewed: 168 (8 UL)
Full Text
Peer Reviewed
See detailGene x Environment Interaction on Developmental Outcomes in Germany: What is the Environment that matters?
Gottschling, Juliana UL; Hahn, Elisabeth; Spinath, Frank M.

in Behavior Genetics (2018, June)

Detailed reference viewed: 20 (0 UL)
Full Text
Peer Reviewed
See detailIntrusion-Tolerant Autonomous Driving
Volp, Marcus UL; Verissimo, Paulo UL

in Proceedings of 2018 IEEE 21st International Symposium on Real-Time Distributed Computing (ISORC) (2018, May 29)

Fully autonomous driving is one if not the killer application for the upcoming decade of real-time systems. However, in the presence of increasingly sophisticated attacks by highly skilled and well ... [more ▼]

Fully autonomous driving is one if not the killer application for the upcoming decade of real-time systems. However, in the presence of increasingly sophisticated attacks by highly skilled and well equipped adversarial teams, autonomous driving must not only guarantee timeliness and hence safety. It must also consider the dependability of the software concerning these properties while the system is facing attacks. For distributed systems, fault-and-intrusion tolerance toolboxes already offer a few solutions to tolerate partial compromise of the system behind a majority of healthy components operating in consensus. In this paper, we present a concept of an intrusion-tolerant architecture for autonomous driving. In such a scenario, predictability and recovery challenges arise from the inclusion of increasingly more complex software on increasingly less predictable hardware. We highlight how an intrusion tolerant design can help solve these issues by allowing timeliness to emerge from a majority of complex components being fast enough, often enough while preserving safety under attack through pre-computed fail safes. [less ▲]

Detailed reference viewed: 61 (10 UL)
Full Text
Peer Reviewed
See detailAcceptability and Acceptance of Autonomous Mobility on Demand: The Impact of an Immersive Experience
Distler, Verena UL; Lallemand, Carine UL; Thierry, Bellet

in Proceedings of the 2018 CHI Conference on Human Factors in Computing Systems (2018, April)

Autonomous vehicles have the potential to fundamentally change existing transportation systems. Beyond legal concerns, these societal evolutions will critically depend on user acceptance. As an emerging ... [more ▼]

Autonomous vehicles have the potential to fundamentally change existing transportation systems. Beyond legal concerns, these societal evolutions will critically depend on user acceptance. As an emerging mode of public transportation [7], Autonomous mobility on demand (AMoD) is of particular interest in this context. The aim of the present study is to identify the main components of acceptability (before first use) and acceptance (after first use) of AMoD, following a user experience (UX) framework. To address this goal, we conducted three workshops (N=14) involving open discussions and a ride in an experimental autonomous shuttle. Using a mixed-methods approach, we measured pre-immersion acceptability before immersing the participants in an on-demand transport scenario, and eventually measured post-immersion acceptance of AMoD. Results show that participants were reassured about safety concerns, however they perceived the AMoD experience as ineffective. Our findings highlight key factors to be taken into account when designing AMoD experiences. [less ▲]

Detailed reference viewed: 71 (13 UL)
Full Text
Peer Reviewed
See detailA UX Approach to Privacy and Security: the Impact of User, Contextual and System-Related Factors
Distler, Verena UL; Lallemand, Carine UL; Koenig, Vincent UL

in CHI Workshop Exploring Individual Diffferences in Privacy (2018, April)

This position paper lays out current and future studies which we conduct on the UX aspects of security and privacy, our goal being to understand which factors influence privacy-related decision-making. We ... [more ▼]

This position paper lays out current and future studies which we conduct on the UX aspects of security and privacy, our goal being to understand which factors influence privacy-related decision-making. We advocate using UX design methods in order to study interindividual differences, system-related and contextual factors involved in privacy and security attitudes and behaviors. These results will contribute to user-tailored and personalized privacy initiatives and guide the design of future technologies. [less ▲]

Detailed reference viewed: 194 (12 UL)
Full Text
Peer Reviewed
See detailHigher Algebra over the Leibniz Operad
Poncin, Norbert UL

in Banach Center Publications (2018, March 18), 113

Detailed reference viewed: 237 (15 UL)
Full Text
Peer Reviewed
See detailInvestigating Siri as a virtual assistant in a learning context
Arend, Béatrice UL

in Proceedings of 12th annual International Technology, Education and Development Conference 2018 (2018, March)

Detailed reference viewed: 56 (5 UL)
Full Text
Peer Reviewed
See detailAdvancing flexible volatile compound sensors using liquid crystals encapsulated in polymer fibers
Reyes, Catherine UL; Lagerwall, Jan UL

in Proceedings of SPIE : The International Society for Optical Engineering (2018, February 08), 10555(105550O),

Until recently, organic vapor sensors using liquid crystals (LCs) have employed rigid glass substrates for confining the LC, and bulky equipment for vapor detection. Previously, we demonstrated that ... [more ▼]

Until recently, organic vapor sensors using liquid crystals (LCs) have employed rigid glass substrates for confining the LC, and bulky equipment for vapor detection. Previously, we demonstrated that coaxially electrospinning nematic LC within the core of polymer fibers provides an alternative and improved form factor for confinement. This enables ppm level sensitivity to harmful industrial organics, such as toluene, while giving the flexibility of textile-like sheets (imparted by polymer encapsulation). Moreover, toluene vapor responses of the [less ▲]

Detailed reference viewed: 79 (2 UL)
Full Text
Peer Reviewed
See detailIdentification and Characterization of Variant Intolerant Sites across Human Protein 3-Dimensional Structures
Iqbal, Sumaiya; Berg Jespersen, Jakob; Perez-Palma, Eduardo et al

in Biophysical Journal (2018, February 02), 114(3, Suppl. 1), 664

The functional interpretation of genetic variation in disease-associated genes is far outpaced by data generation. Existing algorithms for prediction of variant consequences do not adequately distinguish ... [more ▼]

The functional interpretation of genetic variation in disease-associated genes is far outpaced by data generation. Existing algorithms for prediction of variant consequences do not adequately distinguish pathogenic variants from benign rare variants. This lack of statistical and bioinformatics analyses, accompanied by an ever-increasing number of identified variants in biomedical research and clinical applications, has become a major challenge. Established methods to predict the functional effect of genetic variation use the degree of amino acid conservation across species in linear protein sequence alignment. More recent methods include the spatial distribution pattern of known patient and control variants. Here, we propose to combine the linear conservation and spatial constrained based scores to devise a novel score that incorporates 3-dimensional structural properties of amino acid residues, such as the solvent-accessible surface area, degree of flexibility, secondary structure propensity and binding tendency, to quantify the effect of amino acid substitutions. For this study, we develop a framework for large-scale mapping of established linear sequence-based paralog and ortholog conservation scores onto the tertiary structures of human proteins. This framework can be utilized to map the spatial distribution of mutations on solved protein structures as well as homology models. As a proof of concept, using a homology model of the human Nav1.2 voltage-gated sodium channel structure, we observe spatial clustering in distinct domains of mutations, associated with Autism Spectrum Disorder (>20 variants) and Epilepsy (>100 variants), that exert opposing effects on channel function. We are currently characterizing all variants (>300k individuals) found in ClinVar, the largest disease variant database, as well as variants identified in >140k individuals from general population. The variant mapping framework and our score, informed with structural information, will be useful in identifying structural motifs of proteins associated with disease risk. [less ▲]

Detailed reference viewed: 86 (2 UL)
Full Text
Peer Reviewed
See detailRecycling Smart Contracts: Compression of the Ethereum Blockchain.
Fiz Pontiveros, Beltran UL; Norvill, Robert UL; State, Radu UL

in Proceedings of 9th IFIP International Conference on New Technologies, Mobility and Security (NTMS) 2018 (2018, February)

Detailed reference viewed: 105 (7 UL)
Peer Reviewed
See detailHelical light emission from plasmonic vortices via magnetic tapered tip
Maccaferri, Nicolò UL; Gorodetski, Yuri; Garoli, Denis

in Journal of Physics. Conference Series (2018), 961

We investigate an architecture where a plasmonic vortex excited in a gold surface propagates on an adiabatically tapered magnetic tip and detaches to the far-field while carrying a well-defined optical ... [more ▼]

We investigate an architecture where a plasmonic vortex excited in a gold surface propagates on an adiabatically tapered magnetic tip and detaches to the far-field while carrying a well-defined optical angular momentum. We analyze the out-coming light and show that, despite generally high losses of flat magnetic surface, our 3D structure exhibits high energy throughput. Moreover, we show that once a magneto-optical activity is activated inside the magnetic tip a modulation of the total power transmittance is possible. [less ▲]

Detailed reference viewed: 60 (1 UL)
Full Text
Peer Reviewed
See detailA Model for Regulating of Ethical Preferences in Machine Ethics
Baniasadi, Zohreh UL; Parent, Xavier UL; Max, Charles UL et al

in Proceedings of International Conference on Human-Computer Interaction (2018)

Detailed reference viewed: 170 (37 UL)
Full Text
Peer Reviewed
See detailEmpirical Cognitive Study on Abstract Argumentation Semantics
Cramer, Marcos UL; Guillaume, Mathieu UL

in Frontiers in Artificial Intelligence and Applications (2018)

In abstract argumentation theory, multiple argumentation semantics have been proposed that allow to select sets of jointly acceptable arguments from a given set of arguments based on the attack relation ... [more ▼]

In abstract argumentation theory, multiple argumentation semantics have been proposed that allow to select sets of jointly acceptable arguments from a given set of arguments based on the attack relation between arguments. The existence of multiple argumentation semantics raises the question which of these semantics predicts best how humans evaluate arguments, possibly depending on the thematic con- text of the arguments. In this study we report on an empirical cognitive study in which we tested how humans evaluate sets of arguments de- pending on the abstract structure of the attack relation between them. Two pilot studies were performed to validate the intended link between argumentation frameworks and sets of natural language arguments. The main experiment involved a group deliberation phase and made use of three different thematic contexts of the argument sets involved. The data strongly suggest that independently of the thematic contexts that we have considered, strong acceptance and strong rejection according to the CF2 and preferred semantics are a better predictor for human argument acceptance than the grounded semantics (which is identical to strong acceptance/rejection with respect to complete semantics). Furthermore, the data suggest that CF2 semantics predicts human argument acceptance better than preferred semantics, but the data for this comparison is limited to a single thematic context. [less ▲]

Detailed reference viewed: 39 (2 UL)
See detailTombeaux monumentaux d’Arlon/Orolaunum vicus
Ruppert, Christine UL

in Signa (2018), 7

Detailed reference viewed: 31 (2 UL)
Full Text
Peer Reviewed
See detailAssessing binge-watching behaviors: Development of the « Watching TV Series Motives » and the « Binge-Watching Engagement » questionnaires
Flayelle, Maèva UL; Canale, Natale; Maurage, Pierre et al

in Journal of Behavioral Addictions (2018), 7 (Suppl.1)

Detailed reference viewed: 47 (0 UL)
Full Text
Peer Reviewed
See detailFDG-PET and metabolomics in PD-associated GBA variants
Greuel, Andrea; Trezzi, Jean-Pierre; Glaab, Enrico UL et al

in Movement Disorders (2018), 33(2), 599

Detailed reference viewed: 20 (0 UL)
Full Text
Peer Reviewed
See detailTowards a Management Plane for Smart Contracts: Ethereum Case Study
Khan, Nida UL; Lahmadi, Abdelkader; Francois, Jerome et al

in NOMS 2018 - 2018 IEEE/IFIP Network Operations and Management Symposium (2018)

Blockchain is an emerging foundational technology with the potential to create a novel economic and social system. The complexity of the technology poses many challenges and foremost amongst these are ... [more ▼]

Blockchain is an emerging foundational technology with the potential to create a novel economic and social system. The complexity of the technology poses many challenges and foremost amongst these are monitoring and management of blockchain-based decentralized applications. In this paper, we design, implement and evaluate a novel system to enable management operations in smart contracts. A key aspect of our system is that it facilitates the integration of these operations through dedicated ’managing’ smart contracts to provide data filtering as per the role of the smart contract-based application user. We evaluate the overhead costs of such data filtering operations after post-deployment analyses of five categories of smart contracts on the Ethereum public testnet, Rinkeby. We also build a monitoring tool to display public blockchain data using a dashboard coupled with a notification mechanism of any changes in private data to the administrator of the monitored decentralized application. [less ▲]

Detailed reference viewed: 93 (9 UL)
Full Text
Peer Reviewed
See detailMonitoring the transaction selection policy of Bitcoin mining pools
Fiz Pontiveros, Beltran UL; Norvill, Robert UL; State, Radu UL

in NOMS 2018 - 2018 IEEE/IFIP Network Operations and Management Symposium (2018)

Mining pools are collection of workers that work together as a group in order to collaborate in the proof of work and reduce the variance of their rewards when mining. In order to achieve this, Mining ... [more ▼]

Mining pools are collection of workers that work together as a group in order to collaborate in the proof of work and reduce the variance of their rewards when mining. In order to achieve this, Mining pools distribute amongst the workers the task of finding a block so that each worker works on a different subset of the candidate solutions. In most mining pools the selection of transactions to be part of the next block is performed by the pool manager and thus becomes more centralized. A mining Pool is expected to give priority to the most lucrative transactions in order to increase the block reward however changes to the transaction policy done without notification of workers would be difficult to detect. In this paper we treat the transaction selection policy performed by miners as a classification problem; for each block we create a dataset, separate them by mining pool and apply feature selection techniques to extract a vector of importance for each feature. We then track variations in feature importance as new blocks arrive and show using a generated scenario how a change in policy by a mining pool could be detected. [less ▲]

Detailed reference viewed: 81 (7 UL)
Full Text
Peer Reviewed
See detailAre we post-justification? Stout's case for self-knowledge, political justification and public philosophy
Burks, Deven UL

in Ethics, Politics & Society (2018), 1

Must the participant to public discourse have knowledge of her beliefs, attitudes and reasons as well as belief-formation processes to have justified political belief? In this paper, we test this question ... [more ▼]

Must the participant to public discourse have knowledge of her beliefs, attitudes and reasons as well as belief-formation processes to have justified political belief? In this paper, we test this question with reference to Jeffrey Stout’s (2004) approach to public discourse and public philosophy. After defining self- knowledge and justification along the lines of James Pryor (2004), we map thereon Stout’s view of public discourse and public philosophy as democratic piety, earnest storytelling and Brandomian expressive rationality. We then lay out Brian Leiter’s (2016) naturalistic critique of public philosophy as “discursive hygiene” to see whether Stoutian public philosophy survives the former’s emotivist-tribalist gauntlet. Lastly, we find that Leiter’s critique proves less radical than it may appear and requires the moderating influence of a public philosophy like Stout’s. All in all, Stoutian public discourse and public philosophy powerfully illustrates a strong, necessary connection between self-knowledge and political justification. Post-truth is not post-justification. [less ▲]

Detailed reference viewed: 72 (1 UL)
Full Text
Peer Reviewed
See detailDirectionality of Attacks in Natural Language Argumentation
Cramer, Marcos UL; Guillaume, Mathieu UL

in CEUR Workshop Proceedings (2018)

In formal (abstract and structured) argumentation theory, a central notion is that of an attack between a counterargument and the argument that it is challenging. Unlike the notion of an inconsistency ... [more ▼]

In formal (abstract and structured) argumentation theory, a central notion is that of an attack between a counterargument and the argument that it is challenging. Unlike the notion of an inconsistency between two statements in classical logic, this notion of an attack between arguments can be asymmetric, i.e. an argument A can attack an argument B without B attacking A. While this property of the formal systems studied by argumentation theorist has been motivated by considerations about the human practice of argumentation in natural language, there have not been any systematic studies on the connection between the directionality of attacks in argumentation-theoretic formalisms and the way humans actually interpret conflicts between arguments in a non-symmetric way. In this paper, we report on the result of two empirical cognitive studies that aim at filling this gap, one study with ordinary adults (undergraduate students) and one study with adult experts in formal argumentation theory. We interpret the results in light of the notions and distinctions defined in the ASPIC+ framework for structured argumentation, and discuss the relevance of our findings to past and future empirical studies about the link between human argumentation and formal argumentation theory. [less ▲]

Detailed reference viewed: 39 (0 UL)
Full Text
Peer Reviewed
See detailEditionsphilologie und inszenierende Typographie: eine praxeologische Perspektive auf die 'Mein-Kampf'-Edition des Instituts für Zeitgeschichte
Busch, Christopher UL; Ahrens, Moritz

in Editio : Internationales Jahrbuch für Editionswissenschaft = International Yearbook of Textual Criticism and Editorial Science] (2018), 32

Detailed reference viewed: 67 (0 UL)
Full Text
See detailBinge-watching engagement as determined by motivations, impulsivity and emotional reactivity: A cluster analytic approach.
Flayelle, Maèva UL; Maurage, Pierre; Vögele, Claus UL et al

in Alcoholism: Clinical & Experimental Research (2018), 42 (Suppl. 2)

Detailed reference viewed: 39 (3 UL)
Full Text
Peer Reviewed
See detailLegal Design Patterns for Privacy
Haapio, Helena; Hagan, Margaret; Palmirani, Monica et al

in Data Protection / LegalTech Proceedings of the 21st International Legal Informatics Symposium IRIS 2018 (2018)

Fulfilling the legal requirements of mandated disclosure is a challenge in many contexts. Privacy communication is no exception, especially for those who seek to effectively inform individuals about the ... [more ▼]

Fulfilling the legal requirements of mandated disclosure is a challenge in many contexts. Privacy communication is no exception, especially for those who seek to effectively inform individuals about the use of their data. Lawyers across countries and industries are facing recurring problems when (re)writing privacy notices and terms. Visual and interactive design patterns have been suggested as the solution, yet our analysis shows that they are lacking on most privacy policies. This indicates the need for standardization and an actionable pattern library, which we propose in this paper. [less ▲]

Detailed reference viewed: 89 (5 UL)
Full Text
Peer Reviewed
See detailA Parallel Multiscale DEM-VOF Method For Large-Scale Simulations Of Three-Phase Flows
Pozzetti, Gabriele UL; Besseron, Xavier UL; Rousset, Alban UL et al

in Proceedings of ECCM-ECFD 2018 (2018)

A parallel dual-grid multiscale DEM-VOF coupling is here investigated. Dual- grid multiscale couplings have been recently used to address different engineering problems involving the interaction between ... [more ▼]

A parallel dual-grid multiscale DEM-VOF coupling is here investigated. Dual- grid multiscale couplings have been recently used to address different engineering problems involving the interaction between granular phases and complex fluid flows. Nevertheless, previous studies did not focus on the parallel performance of such a coupling and were, therefore, limited to relatively small applications. In this contribution, we propose an insight into the performance of the dual-grid multiscale DEM-VOF method for three- phase flows when operated in parallel. In particular,we focus on a famous benchmark case for three-phase flows and assess the influence of the partitioning algorithm on the scalability of the dual-grid algorithm. [less ▲]

Detailed reference viewed: 70 (24 UL)
Full Text
See detailUnderstanding human need fulfilment to support the design of secure experiences
Distler, Verena UL

in Proceedings of NordiCHI' 18 Doctoral Consortium (2018)

Detailed reference viewed: 33 (11 UL)
Full Text
Peer Reviewed
See detailDevelopment of a Data-Driven Approach based on Kalman filtering for CFD Reactor Analysis
Introini, Carolina; Cammi, Antonio; Lorenzi, Stefano et al

in PHYSOR 2018 (2018)

In the last several years, computer-based simulation has become an important analysis and design tool in many engineering fields. The common practice involves the use of low-fidelity models, which in most ... [more ▼]

In the last several years, computer-based simulation has become an important analysis and design tool in many engineering fields. The common practice involves the use of low-fidelity models, which in most cases are able to provide fairly accurate results while maintaining a low computational cost. However, for complex systems such as nuclear reactors, more detailed models are required for the in-depth analysis of the problem at hand, due for example to the complex geometries of the physical domain. Nevertheless, such models are affected by potentially critical uncertainties and inaccuracies. In this context, the use of data assimilation methods such as the Kalman filter to integrate local experimental data witihin the numerical model looks very promising as a high-fidelity analysis tool. In this work, the focus is the application of such methods to the problem of fluid-dynamics analysis of the reactor. Indeed, in terms of nuclear reactor investigation, a detailed characterization of the coolant behaviour within the reactor core is of manda- tory importance in order to understand, among others, the operating conditions of the system, and the potential occurrence of accident scenarios. In this context, the use of data assimilation methods allows the extraction of information of the thermo-dynamics state of the system in a benchmarked transitory in order to increase the fidelity of the com- putational model. Conversely to the current application of control-oriented black-box in the nuclear energy community, in this work the integration of the data-driven paradigm into the numerical formulation of the CFD problem is proposed. In particular, the al- gorithm outlined embeds the Kalman filter into a segregated predictor-corrector formu- lation, commonly adopted for CFD analysis. Due to the construction of the developed method, one of the main challenges achieved is the preservation of mass-conservation for the thermo-dynamics state during each time instant. As a preliminary verification, the proposed methodology is validated on a benchmark of the lid-driven cavity. The obtained results highlight the efficiency of the proposed method with respect to the state-of-art low fidelity approach. [less ▲]

Detailed reference viewed: 91 (2 UL)
Full Text
Peer Reviewed
See detailComparison of Several RANS Modelling for the Pavia TRIGA Mark II Research Reactor
Introini, Carolina; Cammi, Antonio; Lorenzi, Stefano et al

in Journal of Nuclear Engineering and Radiation Science (2018)

Aim of this work is the comparison of different turbulent models based on the Reynolds Averaged Navier-Stokes (RANS) equations in order to find out which model is the most suitable for the study of the ... [more ▼]

Aim of this work is the comparison of different turbulent models based on the Reynolds Averaged Navier-Stokes (RANS) equations in order to find out which model is the most suitable for the study of the channel thermal-hydraulics of the TRIGA Mark II reactor. Only the steady state behaviour (i.e. the full power stationary operational conditions) of the reactor has been considered. To this end, the RAS (Reynolds-Averaged Simulation) models available in the open source CFD software OpenFOAM have been applied to the most internal channel of the TRIGA and assessed against a Large Eddy Simulation (LES) model. The results of the latter approach, expressed in terms of axial velocity, turbulent viscosity, turbulent kinetic energy, and temperature have been compared with the results obtained by the RAS models available in OpenFOAM (k − ε, k − ω and Reynolds Stress Transport). Heat transfer is taken into account as well by means of the turbulent energy diffusivity parameter. The simulation results demonstrate how, amongst the RAS models, the k − ω SST is the one whose results are closer to the LES simulation. This model seems to be the best one for the treatment of turbulent flow within the TRIGA subchannel, offering a good compromise between accuracy and computational requirements. Since it is much less expensive than an LES model, it can be applied even to full core calculation, in order to obtain accurate results with less computational effort. [less ▲]

Detailed reference viewed: 94 (8 UL)
Full Text
See detailLocally-confined electrodeposition of Cu(In,Ga)Se2micro islands for micro-concentrator solar cells.
Correa, David; Siopa, Daniel UL; Salomé, Pedro M.P. et al

in IEEE (2018)

Detailed reference viewed: 97 (4 UL)
Full Text
Peer Reviewed
See detailJames Bond's Most Secret Weapon
Leprévost, Franck UL

in Proceedings of the 3rd International Conference on Applications in Information Technology (2018)

This conference presents in a non-conventional way secret-key and public-key cryptology from its origins to the present days.

Detailed reference viewed: 76 (4 UL)
Full Text
Peer Reviewed
See detailCognitive biases in pain: current challenges, future directions and treatment opportunities
Van Ryckeghem, Dimitri UL

in Canadian Journal of Pain (2018)

Cognitive biases are a core component of contemporary cognitive-affective models that try to explain pain experience, distress and disability in children and adults experiencing pain. The idea that ... [more ▼]

Cognitive biases are a core component of contemporary cognitive-affective models that try to explain pain experience, distress and disability in children and adults experiencing pain. The idea that children and adults with pain show cognitive biases for pain-related information, i.e. they selectively attend to pain-related information at the cost of other information (attentional bias), interpret ambiguous stimuli as pain-related (interpretation bias) or have biased memories for painful events (memory bias), has been particularly influential in this context. Notwithstanding the considerable progress made in the understanding of cognitive biases related to pain and threat, a number of questions remains unanswered and future challenges linger. A first challenge is to further delineate the characteristics of cognitive biases, including their content specificity and dynamics. A second challenge relates to the understanding of how cognitive biases interrelate with each other and possibly reinforce one another. A third challenge relates to the translation of findings on cognitive biases for pain into clear strategies and recommendations to optimize and evaluate pain treatment programs. Presenters in this symposium will address each of the above-mentioned lingering challenges by both critically reviewing the available evidence on cognitive biases in children and/ or adults experiencing pain and presenting novel research using innovative study set-ups and unique methods for assessing and modifying cognitive biases in children and adults experiencing pain. [less ▲]

Detailed reference viewed: 37 (9 UL)
Full Text
See detailLe droit commun et l'avenir du droit luxembourgeois
Kinsch, Patrick UL

in Actes de la Section des sciences morales et politiques (2018), XXI

Le droit commun est un ensemble de règles ordinaires, censées être équilibrées, qui évite le spectaculaire, l’exorbitant, les privilèges. En droit privé, c’est (pour faire bref et un peu inexact) le droit ... [more ▼]

Le droit commun est un ensemble de règles ordinaires, censées être équilibrées, qui évite le spectaculaire, l’exorbitant, les privilèges. En droit privé, c’est (pour faire bref et un peu inexact) le droit du Code civil ; au-delà du droit civil, il existe du droit commun dans toutes les branches du droit, même en droit fiscal. Ne sous-estimons pas le droit commun ; il est précieux. Mais a-t-il un véritable avenir au Luxembourg ? Il a quelques alliés, il est vrai : le contrôle de la constitutionnalité des lois, et le contrôle des clauses abusives dans les contrats. Deux puissants facteurs jouent cependant contre lui : 1° le manque, paradoxal mais réel, de ressources qui permettraient de faire évoluer le droit commun, en particulier sur le plan législatif ; 2° le souhait de le remplacer par du droit dérogatoire (et compétitif dans le marché international des normes), qui n’a aucune des caractéristiques, rappelées ci-dessus, du droit commun. [less ▲]

Detailed reference viewed: 97 (17 UL)
Full Text
See detailModellierung eines PVT-basierten Wärmepumpensystems auf der Basis von CO2 Direktverdampfung
Rullof, Johannes UL; Lambers, Klaus Jürgen; Blieske, Ulf et al

in Proceedings of Deutsche Kälte- und Klimatagung DKV 2018 (2018)

Die Systemkombination aus Wärmepumpe und solarthermischen Absorber, basierend auf freier Konvektion und Strahlung, und Photovoltaik (PV) in einem Modul (PVT-Modul) kann aufgrund der Reduzierung des ... [more ▼]

Die Systemkombination aus Wärmepumpe und solarthermischen Absorber, basierend auf freier Konvektion und Strahlung, und Photovoltaik (PV) in einem Modul (PVT-Modul) kann aufgrund der Reduzierung des Heizwärmebedarfs von Gebäuden und des verstärkten Betriebs von Wärmepumpen während der Niedrigstrompreiszeiten am Tage und dem damit verbundenen höheren Strahlungsanteil der Umweltwärme zukünftig eine Alternative zu zwangskonvektions-basierten Luft-Wärmepumpen sein. Der Beitrag beschäftigt sich mit einem CO2-Wärmepumpensystem, bestehend aus einem neuartigen Solar-Hybridmodul, welches einen mikrokanal-basierten Verdampfer einer CO2-Wärmepumpe mit einem PV-Modul vereint (PVT-direkt). Um die Machbarkeit des neuartigen PVT-direkt-Wärmepumpensystems zu demonstrieren, wird im Rahmen eines Forschungsprojekts ein funktionsfähiges PVT-direkt-Modul konstruiert und schließlich als Teil eines CO2-Wärmepumpensystems getestet und modelliert. Die Besonderheit der Kombination eines thermischen Absorbers mit einer Wärmepumpe liegt in der Erschließung der Solarenergie und Umgebungsenergie als Energiequelle. Hierbei ist die Kenntnis über die thermische Leistung des PVT-Moduls unter anderem durch den konvektiven Wärmeübergang zwischen dem PVT-Modul und der Umgebung relevant. Sowohl der Modulneigungswinkel (Anströmwinkel) und die Windrichtung (Azimutwinkel) haben einen nicht zu vernachlässigenden Einfluss auf den resultierenden Wärmeübergangskoeffi-zienten der erzwungenen Konvektion. Da im Rahmen einer Literaturrecherche keine für das PVT-Modul direkt zu übertragenden experimentelle Untersuchungen und Berechnungsgrundlagen zur Bestimmung des konvektiven Wärmeübergangs gefunden werden konnten, wurde mit Hilfe der Software ANSYS Fluent eine CFD-Simulation zum konvektiven Wärmeübergang am PVT-Modul durchgeführt, deren Ergebnisse in dieser Arbeit präsentiert werden. [less ▲]

Detailed reference viewed: 33 (5 UL)
Full Text
Peer Reviewed
See detailDevelopment of a Control Strategy for a PVT-based CO2 Heat Pump
Rullof, Johannes UL; Lambers, Klaus Jürgen; Blieske, Ulf et al

in Proceedings of 7th International Energy and Sustainability Conference (IESC) (2018)

In recent years, the possibility of combining photovoltaics (PV) and solar thermal collectors into one solar hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and ... [more ▼]

In recent years, the possibility of combining photovoltaics (PV) and solar thermal collectors into one solar hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and electrical energy at the same time. Since the efficiency of a photovoltaic module decreases with increasing temperature, the temperature of the heat transfer media is often limited to about 30 °C and the PVT-module is combined with a heat pump, which increases the temperature on the “warm side”. A common approach is to integrate the PVT-module directly as an evaporator in a heat pump system (PVT-direct). This paper presents the development of a control strategy for a PVT-based CO2 heat pump that takes into account solar radiation, ambient temperature, wind speed, evaporator temperature and compressor power. The developed control strategy provides different operating modes depending on the solar radiation supply as well as the ambient temperature. [less ▲]

Detailed reference viewed: 57 (2 UL)
Full Text
Peer Reviewed
See detailElliptic Curves Discrete Logarithm Problem over a Finite Field Fp and p-adic Approximations
Leprévost, Franck UL; Bernard, Nicolas UL; Bouvry, Pascal UL

in Proceedings of the 3rd International Conference on Applications in Information Technology (ICAIT-2018) (2018)

These notes summarize some computations conducted around the Elliptic Curves Discrete Logarithm Problem (ECDLP) over a finite field Fp.

Detailed reference viewed: 55 (0 UL)
Full Text
Peer Reviewed
See detailThe low-dimensional algebraic cohomology of the Witt and the Virasoro algebra
Ecker, Jill Marie-Anne UL; Schlichenmaier, Martin UL

in Journal of Physics. Conference Series (2018)

Detailed reference viewed: 71 (7 UL)
Full Text
See detailChancen und Barrieren Inklusiver Bildung im Vergleich: Lernen von Anderen
Powell, Justin J W UL

in Schriftenreihe Eine für Alle — Die inklusive Schule für die Demokratie (2018), 3

Das Menschenrecht auf Inklusive Bildung als globale Norm – und als Thema der Bildungsforschung in Deutschland. Die hohe und gestiegene Bedeutung Inklusiver Bildung für Gesellschaften und Individuen wird ... [more ▼]

Das Menschenrecht auf Inklusive Bildung als globale Norm – und als Thema der Bildungsforschung in Deutschland. Die hohe und gestiegene Bedeutung Inklusiver Bildung für Gesellschaften und Individuen wird global, national, regional und lokal von verschiedensten Akteur*innen hervorgehoben und medial sehr breit rezipiert—und zunehmend auch wissenschaftlich multidisziplinär diskutiert. Durch Initiativen wie „Education for All“ (UNESCO, 2015), die Konvention über die Rechte von Menschen mit Behinderung der Vereinten Nationen (UN-BRK, seit 2006), welche inklusive Bildung als Menschenrecht verankert, oder die UN Millennium Development Goals (www.un.org/millenniumgoals) wird das Thema Inklusion verstärkt in Bildungspolitik und -praxis aufgegriffen. Innerhalb einer Dekade haben über 170 Länder die UN-BRK ratifiziert (United Nations, 2017). Artikel 24 definiert Inklusive Bildung als Menschenrecht: „Die Vertragsstaaten (sichern)... den Zugang zu einem inklusiven, hochwertigen und unentgeltlichen Unterricht“ (Art. 24, UN-BRK). Damit wird inklusive Bildung zur globalen Norm und zum einklagbaren Recht entlang des Lebenslaufs. In diesem Beitrag wird anhand ausgewählter Vergleiche aufgezeigt, wie sich die Expansion und Persistenz der schulischen Segregation anstatt der Ausweitung der Inklusion vollzieht. Dabei wurde ein langsamer Wandel statt Transformation dieser komplexen Bildungssysteme konstatiert. Im Ländervergleich wurden immer wieder markante Divergenzen festgestellt, wonach die unterschiedlichen „institutionellen Logiken“ dieser Systeme sichtbar wurden. Abschließend lässt sich festhalten, dass die Förderquote wohl weiter steigen wird wegen größerem Bedarf (oder wahrgenommenen Förderbedarfs), erhöhter Standards und gesteigerter Rechenschaftspflicht als Teile der Governance von Bildung. Sonderpädagogische Förderung nimmt seit Jahrzehnten weltweit zu, oft in Sonderschulen oder -klassen. Es mag paradox erscheinen, dass gleichzeitig sowohl segregierende als auch inklusive Lernumwelten expandieren. Der Grund: Die Verflechtung und Wechselwirkungen zwischen sonderpädagogischen Fördersystemen, allgemeiner Bildung und anderen Institutionen sowie die Interessen der beteiligten Professionen verhindern die Transformation hin zur schulischen Inklusion für alle. Gleichzeitig schreitet dennoch auch in den Bildungssystemen, die hochgradig selektiv und segregiert sind, Inklusive Bildung voran. Vergleichende Forschung verdeutlicht vielfältige Grenzen, aber auch Facilitatoren der Inklusion auf unterschiedlichen Ebenen. Die Ratifizierung der UN-BRK in Deutschland hat die Notwendigkeit unterstrichen, die Bildungssysteme auf Länder- und lokaler Ebene umzubauen und den Wandel zu erforschen. Die UN-BRK stärkt Advokaten der Inklusiven Bildung nachhaltig. Auch aufgrund des Bil- dungsföderalismus wird die Implementierung weiterhin ein schrittweiser, pfadabhängiger Prozess und keine fundamentale Transformation sein. Gerade in föderalen Ländern wie Deutschland und den USA gibt es eine Persistenz einzelstaatlicher Disparitäten trotz (inter-)nationaler Ziele, Normen und völkerrechtlicher Verträge, die es weiter zu untersuchen und zu implementieren gilt. Die Chance, die solche Systeme bieten, ist die Kontrastierung der diversen Pfade hin zur Inklusiven Bildung und die Chance zur Politik der Vielfalt, die zu einer Schule für alle und zur Pädagogik der Vielfalt passt. [less ▲]

Detailed reference viewed: 182 (8 UL)
Full Text
Peer Reviewed
See detailDiscovery and pathogenicity assessment of neuropathology-associated gene variants
Neupert, Lisa-Marie; May, Patrick UL; Kobow, Katja et al

in Epilepsia (2017, December 08), 58(Suppl.5), 174

Germline and brain-specific somatic variants have been reported as an underlying cause in patients with epilepsy-associated neuropathologies, including focal cortical dysplasias (FCDs) and long-term ... [more ▼]

Germline and brain-specific somatic variants have been reported as an underlying cause in patients with epilepsy-associated neuropathologies, including focal cortical dysplasias (FCDs) and long-term epilepsy associated tumors (LEAT). However, evaluation of identified neuropathology associated variants in genetic screens is complex since not all observed variants contribute to the etiology of neuropathologies not even in genuinely disease-associated genes. Here, we critically reevaluated the pathogenicity of 12 previously published disease-related genes and of 79 neuropathology-associated missense variants listed in the PubMed and ClinVar databases. We (1) assessed the evolutionary gene constraint using the pLI and the missense z score, (2) used the latest American College of Medical Genetics and Genomics (ACMG) guidelines, and (3) performed bioinformatic variant pathogenicity prediction analyses using PolyPhen-2, CADD and GERP. Constraint analysis classified only seven out of 12 genes to be likely disease-associated. Furthermore, 78 (89%) of 88 neuropathology-associated missense variants were classified as being of unknown significance (VUS) and only 10 (11%) as being likely pathogenic (LPII). Pathogenicity prediction yielded a discrimination between LPII variants and a discrimination for VUS compared with rare variant scores from individuals present in the Genome Aggregation Database (gnomAD). In summary, our results demonstrate that interpretation of variants associated with neuropathologies is complex while the application of current ACMG guidelines including bioinformatic pathogenicity prediction can help improving variant evaluation. Furthermore, we will augment this set of literature-identified variants at the conference by results from our variant screen using self-generated deep sequencing data in >150 candidate genes in >50 patients not yet analyzed. [less ▲]

Detailed reference viewed: 77 (2 UL)