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See detailFacial Expression Recognition via Joint Deep Learning of RGB-Depth Map Latent Representations
Oyedotun, Oyebade UL; Demisse, Girum UL; Shabayek, Abd El Rahman UL et al

in 2017 IEEE International Conference on Computer Vision Workshop (ICCVW) (2017, August 21)

Humans use facial expressions successfully for conveying their emotional states. However, replicating such success in the human-computer interaction domain is an active research problem. In this paper, we ... [more ▼]

Humans use facial expressions successfully for conveying their emotional states. However, replicating such success in the human-computer interaction domain is an active research problem. In this paper, we propose deep convolutional neural network (DCNN) for joint learning of robust facial expression features from fused RGB and depth map latent representations. We posit that learning jointly from both modalities result in a more robust classifier for facial expression recognition (FER) as opposed to learning from either of the modalities independently. Particularly, we construct a learning pipeline that allows us to learn several hierarchical levels of feature representations and then perform the fusion of RGB and depth map latent representations for joint learning of facial expressions. Our experimental results on the BU-3DFE dataset validate the proposed fusion approach, as a model learned from the joint modalities outperforms models learned from either of the modalities. [less ▲]

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See detailA "Flagship University" for Luxembourg?
Harmsen, Robert UL

Article for general public (2017)

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See detailEvolution systems of measures and semigroup properties on evolving manifolds
Cheng, Li Juan UL; Thalmaier, Anton UL

E-print/Working paper (2017)

An evolving Riemannian manifold (M,g_t)_{t\in I} consists of a smooth d-dimensional manifold M, equipped with a geometric flow g_t of complete Riemannian metrics, parametrized by I=(-\infty,T). Given an ... [more ▼]

An evolving Riemannian manifold (M,g_t)_{t\in I} consists of a smooth d-dimensional manifold M, equipped with a geometric flow g_t of complete Riemannian metrics, parametrized by I=(-\infty,T). Given an additional C^{1,1} family of vector fields (Z_t)_{t\in I} on M. We study the family of operators L_t=\Delta_t +Z_t where \Delta_t denotes the Laplacian with respect to the metric g_t. We first give sufficient conditions, in terms of space-time Lyapunov functions, for non-explosion of the diffusion generated by L_t, and for existence of evolution systems of probability measures associated to it. Coupling methods are used to establish uniqueness of the evolution systems under suitable curvature conditions. Adopting such a unique system of probability measures as reference measures, we characterize supercontractivity, hypercontractivity and ultraboundedness of the corresponding time-inhomogeneous semigroup. To this end, gradient estimates and a family of (super-)logarithmic Sobolev inequalities are established. [less ▲]

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See detailPrototype Incorporated Emotional Neural Network (PI-EmNN)
Oyedotun, Oyebade UL; Khashman, Adnan

in IEEE Transactions on Neural Networks and Learning Systems (2017)

Artificial neural networks (ANNs) aim to simulate the biological neural activities. Interestingly, many ‘engineering’ prospects in ANN have relied on motivations from cognition and psychology studies. So ... [more ▼]

Artificial neural networks (ANNs) aim to simulate the biological neural activities. Interestingly, many ‘engineering’ prospects in ANN have relied on motivations from cognition and psychology studies. So far, two important learning theories that have been subject of active research are the prototype and adaptive learning theories. The learning rules employed for ANNs can be related to adaptive learning theory, where several examples of the different classes in a task are supplied to the network for adjusting internal parameters. Conversely, prototype learning theory uses prototypes (representative examples); usually, one prototype per class of the different classes contained in the task. These prototypes are supplied for systematic matching with new examples so that class association can be achieved. In this paper, we propose and implement a novel neural network algorithm based on modifying the emotional neural network (EmNN) model to unify the prototype and adaptive learning theories. We refer to our new model as “PI-EmNN” (Prototype-Incorporated Emotional Neural Network). Furthermore, we apply the proposed model to two real-life challenging tasks, namely; static hand gesture recognition and face recognition, and compare the result to those obtained using the popular back propagation neural network (BPNN), emotional back propagation neural network (EmNN), deep networks and an exemplar classification model, k-nearest neighbor (k-NN). [less ▲]

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

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

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

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

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

Scientific Conference (2017, August 06)

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

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

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

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

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

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

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See detailPanel participant
Greiff, Samuel UL

Scientific Conference (2017, August)

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

Scientific Conference (2017, August)

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

Scientific Conference (2017, August)

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

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

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See detailAssistance administrative internationale, procédures luxembourgeoises et droits fondamentaux: Quelques réflexions au lendemain de l'arrêt Berlioz
Chaouche, Fatima UL; Sinnig, Julia UL

in Journal des Tribunaux Luxembourg (2017), 52

Le 16 mai 2017, la Cour de justice de l’Union européenne (C.J.U.E.), réunie en grande chambre, rendait un arrêt particulièrement attendu en matière d’échange de renseignements sur demande : l’arrêt ... [more ▼]

Le 16 mai 2017, la Cour de justice de l’Union européenne (C.J.U.E.), réunie en grande chambre, rendait un arrêt particulièrement attendu en matière d’échange de renseignements sur demande : l’arrêt Berlioz. L’affaire, à l’origine d’un renvoi préjudiciel introduit par la Cour administrative luxembourgeoise, consacre l’applicabilité des droits fondamentaux de l’Union à l’échange transfrontière de données à caractère fiscal. Cet arrêt vient ainsi mettre en péril l’option retenue par le législateur luxembourgeois qui avait, sous la pression du Forum mondial, supprimé en novembre 2014, le recours en annulation dont pouvaient se prévaloir les personnes et tiers concernés par une demande d’échange de renseignements. Si l’arrêt Berlioz a été salué par de nombreux commentateurs, il serait pour autant erroné de voir en cette décision une quelconque victoire en faveur des contribuables faisant l’objet d’une enquête fiscale internationale. Les limites à la notification préalable des personnes vérifiées, l’élargissement de la norme dite de pertinence vraisemblable ou encore la généralisation progressive de l’échange automatique alimentent, bien au contraire, une inégalité procédurale entre administrations fiscales surpuissantes et contribuables contrôlés. [less ▲]

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

Scientific Conference (2017, August)

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

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

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See detailAn Integrated Approach for Effective Injection Vulnerability Analysis of Web Applications through Security Slicing and Hybrid Constraint Solving
Thome, Julian UL; Shar, Lwin Khin UL; Bianculli, Domenico UL et al

Report (2017)

Malicious users can attack Web applications by exploiting injection vulnerabilities in the source code. This work addresses the challenge of detecting injection vulnerabilities in a scalable and effective ... [more ▼]

Malicious users can attack Web applications by exploiting injection vulnerabilities in the source code. This work addresses the challenge of detecting injection vulnerabilities in a scalable and effective way. We propose an integrated approach that seamlessly combines security slicing with hybrid constraint solving, i.e., constraint solving based on a combination of automata-based solving and meta-heuristic search. We use static analysis to extract minimal program slices relevant to security from Web programs and to generate attack conditions. We then apply hybrid constraint solving to determine the satisfiability of attack conditions and thus detect vulnerabilities. The experimental results, using a benchmark suite comprising nine diverse and representative Web applications, show that our approach (implemented in the JOACO tool) is significantly more effective at detecting injection vulnerabilities than state-of-the-art approaches, achieving 98% recall, without producing any false alarm. We also compared the constraint solving module of our approach with state-of-the-art constraint solvers, using five different benchmark suites; our approach correctly solved the highest number of constraints (43177 out of 43184), without producing any incorrect result, and was the one with the least number of time-out/failing cases. In both scenarios, the execution time was practically acceptable, given the offline nature of vulnerability detection. [less ▲]

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

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

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

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

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See detailKoszul-Tate resolutions as cofibrant replacements of algebras over differential operators
Di Brino, Gennaro; Pistalo, Damjan UL; Poncin, Norbert UL

E-print/Working paper (2017)

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See detailFeedforward Chemical Neural Network: An In Silico Chemical System That Learns XOR
Blount, Drew; Banda, Peter UL; Teuscher, Christof et al

in Artificial Life (2017), 23(3), 295-317

Inspired by natural biochemicals that perform complex information processing within living cells, we design and simulate a chemically implemented feedforward neural network, which learns by a novel ... [more ▼]

Inspired by natural biochemicals that perform complex information processing within living cells, we design and simulate a chemically implemented feedforward neural network, which learns by a novel chemical-reaction-based analogue of backpropagation. Our network is implemented in a simulated chemical system, where individual neurons are separated from each other by semipermeable cell-like membranes. Our compartmentalized, modular design allows a variety of network topologies to be constructed from the same building blocks. This brings us towards general-purpose, adaptive learning in chemico: wet machine learning in an embodied dynamical system. [less ▲]

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See detailOn Koszul-Tate resolutions and Sullivan models
Pistalo, Damjan UL; Poncin, Norbert UL

E-print/Working paper (2017)

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See detailReal-time Error Control for Surgical Simulation: Application to Percutaneous Interventions
Bui, Huu Phuoc UL; Tomar, Satyendra UL; Courtecuisse, Hadrien et al

Presentation (2017, August)

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