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See detailVerification of design models of cyber-physical systems specified in Simulink
Gaaloul, Khouloud UL

Doctoral thesis (2021)

Recent advances in cyber-physical systems (CPS) have allowed highly available and approachable technologies with interconnected systems between the physical assets and the computational software ... [more ▼]

Recent advances in cyber-physical systems (CPS) have allowed highly available and approachable technologies with interconnected systems between the physical assets and the computational software components. This has resulted in more complex systems with wider capabilities. For example, they can be applied in various domains such as safe transport, efficient medical devices, integrated systems, critical infrastructure control and more. The development of such critical systems requires advanced new models, algorithms, methods and tools to verify and validate the software components and the entire system. The verification of cyber-physical systems has become challenging: (1) The complex and dynamical behaviour of systems requires resilient automated monitors and test oracles that can cope with time-varying variables of CPS. (2) Given the wide range of existing verification and testing techniques from formal to empirical methods, there is no clear guidance as to how different techniques fare in the context of CPS. (3) Due to serious issues when applying exhaustive verification to complex systems, a common practice is needed to verify system components separately. This requires adding implicit assumptions about the operational environment of system components to ensure correct verification. However, identifying environment assumptions for cyber-physical systems with complex, mathematical behaviors is not trivial. In this dissertation, we focus on addressing these challenges. In this dissertation, we propose a set of effective approaches to verify design models of CPS. The work presented in this dissertation is motivated by ESAIL maritime micro-satellite system, developed by LuxSpace, a leading provider of space systems, applications and services in Luxembourg. In addition to ESAIL, we use a benchmark of eleven public-domain Simulink models provided by Lockheed Martin, which are representative of different categories of CPS models in the aerospace and defence sector. To address the aforementioned challenges, we propose (1) an automated approach to translate CPS requirements specified in a logic-based language into test oracles specified in Simulink. The generated oracles are able to deal with CPS complex behaviours and interactions with the system environment; (2) An empirical study to evaluate the fault-finding capabilities of model testing and model checking techniques for Simulink models. We also provide a categorization of model types and a set of common logical patterns for CPS requirements; (3) An automated approach to synthesize environment assumptions for a component under analysis by combining search-based testing, machine learning and model checking procedures. We also propose a novel technique to guide the test generation based on the feedback received from the machine learning process; and (4) An extension of (3) to learn more complex assumptions with arithmetic expressions over multiple signals and numerical variables. [less ▲]

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See detailQKD parameter estimation by two-universal hashing leads to faster convergence to the asymptotic rate
Ostrev, Dimiter UL

E-print/Working paper (2021)

This paper proposes and proves security of a QKD protocol which uses two-universal hashing instead of random sampling to estimate the number of bit flip and phase flip errors. For this protocol, the ... [more ▼]

This paper proposes and proves security of a QKD protocol which uses two-universal hashing instead of random sampling to estimate the number of bit flip and phase flip errors. For this protocol, the difference between asymptotic and finite key rate decreases with the number $n$ of qubits as $cn^{-1}$, where $c$ depends on the security parameter. For comparison, the same difference decreases no faster than $c'n^{-1/3}$ for an optimized protocol that uses random sampling and has the same asymptotic rate, where $c'$ depends on the security parameter and the error rate. [less ▲]

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See detailEconomic development, weather shocks and child marriage in South Asia: A machine learning approach
Dietrich, Stephan; Meysonnat, Aline; Rosales, Francisco et al

E-print/Working paper (2021)

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See detailLa cybersecurity come bene pubblico: alcune riflessioni normative a partire dai recenti sviluppi nel diritto UE
Brighi, Raffaella; Chiara, Pier Giorgio UL

in Federalismi.it (2021), 21

The article casts the light on how and to what extent the recent EU legislative developments can uphold the thesis that would identify cybersecurity as a public good, in particular, taking into account ... [more ▼]

The article casts the light on how and to what extent the recent EU legislative developments can uphold the thesis that would identify cybersecurity as a public good, in particular, taking into account systems’ robustness. The doctrine of the public good, which is typically an economic concept, in its normative dimension reveals a framework of shared responsibilities, in view of the common interest in having a satisfactory level of security of the information systems at the basis of our societies. Improving cybersecurity is essential, on the one hand, to trust and benefit from innovation, connectivity and automation; on the other hand, for safeguarding fundamental rights and freedoms, including the rights to privacy and to the protection of personal data, and the freedom of expression and information. Against this background, the new strategy of the European Commission on cybersecurity, the proposal for an NIS 2.0 Directive and, at a lower level of abstraction, the inclusion of minimum cybersecurity requirements for connected devices in the Directives and Regulations of the “New Legislative Framework” (NLF), testify the firm will of the Commission to outline a clear, coherent and inclusive regulatory framework, in order to increase the global level of security within the Union. [less ▲]

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See detailRussian Migration in Luxemburg. Virtual Museum.
Ganschow, Inna UL

Learning material (2021)

This virtual museum is dedicated to Russian migration in Luxembourg since the late 19th century. The basis for the early 20th century is the exhibition on the first Russian migrants in Luxembourg, created ... [more ▼]

This virtual museum is dedicated to Russian migration in Luxembourg since the late 19th century. The basis for the early 20th century is the exhibition on the first Russian migrants in Luxembourg, created by the Center for Documentation of Humane Migration in Dudelange, Luxembourg (CDMH) and the Luxembourg Center for Contemporary and Digital History (C2DH, University of Luxembourg), which took place in Gare-Usine in Dudelange from March 2020 until August 2021. The online collection of the photographs, objects and texts from the exhibition are presented here on Hypotheses.org. The initiative to create a virtual museum belongs to the Russian Center for Science and Culture (Russkiy Dom) in Luxemburg. This collection will be replenished with additional items and documents, since the history of Forced Labor of Soviet Citizens in Luxembourg during the WII is a research topic of C2DH in 2021-2024. This website is addressed to academic readers (students, researchers, teachers), as well as readers interested in the history of Russia, Luxembourg and the history of migration. [less ▲]

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See detailÉlections fédérales 2021 : l’ère après-Merkel
Miessen, Thomas; Brüll, Christoph UL

Article for general public (2021)

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See detailGlobal Governance. A Short History of Debates Born with the Telegraph and Popularized by the Internet
Musiani, Francesca; Schafer, Valerie UL

in Musiani, Francesca; Schafer, Valerie (Eds.) Global Governance. A Short History of Debates Born with the Telegraph and Popularized by the Internet (2021, September)

Scholars have successfully attempted to historicize global governance, comparing the Internet to telephone and broadcasting, from a primarily legal standpoint. Among these scholars, historians have also ... [more ▼]

Scholars have successfully attempted to historicize global governance, comparing the Internet to telephone and broadcasting, from a primarily legal standpoint. Among these scholars, historians have also studied particular issues that are relevant to Internet governance, e.g. openness and net neutrality. History is relevant for the concept of global governance for at least two reasons: to historicize the concept in itself through the Internet/digital age (the evolution and enrichment of the notion in the past 30 years, with key turning points such as the creation of ICANN and WSIS) and to flesh out continuities through time with other “global media” or “global issues,” such as international standardization, multi-stakeholderism, and communication rights. This chapter addresses these issues at three levels: periodization of the key concept of “global governance” since the 90s; evolution of the state of the art/research on global (Internet) governance; analysis of global governance in the broader field of media and communication. [less ▲]

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See detailMoral Judgment in Video Games: Effects of Medium, Moral Intuitions and Media-Based Empathy
Grohmann, Lara; Holl, Elisabeth UL; Melzer, André UL

Scientific Conference (2021, September)

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See detailAn Integrative Model of Moral Processing for the Video Game Medium
Melzer, André UL; Holl, Elisabeth UL

Scientific Conference (2021, September)

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See detailLe droit à la sauce piquante n°24 - Septembre 2021
Hiez, David UL; Laurent, Rémi

in Le droit à la sauce piquante (2021), 24

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See detailValue Stream Mapping (VSM) to Evaluate and Visualize Interrelated Process-Chains Regarding Circular Economy
Mangers, Jeff UL; Minoufekr, Meysam UL; Plapper, Peter UL

in Advances in Production Management Systems. Artificial Intelligence for Sustainable and Resilient Production Systems (2021, August 31), 633

The concept of circular economy (CE) aims to close and slow resource loops without neglecting the goals of sustainable development. Recently, the concept received encouraging attention among researchers ... [more ▼]

The concept of circular economy (CE) aims to close and slow resource loops without neglecting the goals of sustainable development. Recently, the concept received encouraging attention among researchers and business experts to be a convenient solution to move away from the finite linear economy concept to a more sustainable solution. However, this change of paradigm is only possible if we consider systems in a holistic manner and can localize the preventing hurdles. Value stream mapping (VSM) is a commonly known lean method, used to develop current state visualization of product and information flows within organization, helping to seek weaknesses and improve process flows. The motivation of this paper is a new C-VSM model, which enables its users to evaluate and visualize connected process-chains regarding CE on different levels in a holistic manner. For this purpose, the traditional VSM model was adapted towards the needs and requirements of CE through the application of a new representation method, additional indicators, and an appropriated evaluation system. C-VSM is in line with the current political and industrial objectives to apply CE principles by enabling a holistic reflection and consideration of supply-chains (SCs) on different levels. The model itself is validated through an extensive cross-company case study. [less ▲]

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See detailNormative coherence for development – What relevance for responsive regionalism?
Koff, Harlan UL; Häbel, Sandra UL

in Development Policy Review (2021)

Without a normative dimension, transformative development risks reproducing traditional economic development. In this special issue we focus on norm implementation in different world regions through the ... [more ▼]

Without a normative dimension, transformative development risks reproducing traditional economic development. In this special issue we focus on norm implementation in different world regions through the lens of normative coherence for development. This special issue indicates that regions are an important interlocutor between the global, national, and sub-national level and, as such, are crucial for implementing the sustainable development agenda. The articles show, however, that to date normative coherence for development has not been achieved due to overriding priorities and technical approaches to policy coherence for development. With this special issue we aim to draw more attention to the topic of normative coherence for development and show that policies need to be adjusted in order to reflect the normative dimension of sustainable development. [less ▲]

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See detailRole of higher-order effects in spin-misalignment small-angle neutron scattering of high-pressure torsion nickel
Oba, Yojiro; Bersweiler, Mathias UL; Titov, Ivan et al

in Physical Review Materials (2021), 5

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See detailAlmost global convergence to practical synchronization in the generalized Kuramoto model on networks over the n-sphere
Markdahl, Johan UL; Proverbio, Daniele UL; Mi, La et al

in Communications Physics (2021), 4

From the flashing of fireflies to autonomous robot swarms, synchronization phenomena are ubiquitous in nature and technology. They are commonly described by the Kuramoto model that, in this paper, we ... [more ▼]

From the flashing of fireflies to autonomous robot swarms, synchronization phenomena are ubiquitous in nature and technology. They are commonly described by the Kuramoto model that, in this paper, we generalise to networks over n-dimensional spheres. We show that, for almost all initial conditions, the sphere model converges to a set with small diameter if the model parameters satisfy a given bound. Moreover, for even n, a special case of the generalized model can achieve phase synchronization with nonidentical frequency parameters. These results contrast with the standard n = 1 Kuramoto model, which is multistable (i.e., has multiple equilibria), and converges to phase synchronization only if the frequency parameters are identical. Hence, this paper shows that the generalized network Kuramoto models for n ≥ 2 displays more coherent and predictable behavior than the standard n = 1 model, a desirable property both in flocks of animals and for robot control. [less ▲]

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See detailOptimal Motion Planning and Control with Safety Guarantees for Aerial Robots
Castillo López, Manuel UL

Doctoral thesis (2021)

Autonomous aerial robots are expected to revolutionize many industries, such as construction, transportation or even space exploration. However, to target an industry where different robots and humans are ... [more ▼]

Autonomous aerial robots are expected to revolutionize many industries, such as construction, transportation or even space exploration. However, to target an industry where different robots and humans are meant to share the same space our algorithms need to provide safety and efficiency guarantees. Navigating autonomously in these kind of environments poses a great challenge. We may face a significant number of obstacles, and we can only estimate where they are and where they are expected to be, but not exactly. Dealing with these uncertainties is a challenging problem in most robotics applications, including motion planning and control. During the last decade, major contributions have established the theoretical basis upon which optimal motion planning and control with safety guarantees can be achieved. However, they involve a high computational cost that scales exponentially with the number of obstacles, rendering a limited domain of robotic applications. The main contribution of this thesis provides an efficient, scalable and safe approximation to this problem, allowing its application to embedded systems with fast dynamics such as aerial robots. This thesis also includes an additional contribution that allow these methods to plan longer trajectories with a minimal computational footprint, allowing to better anticipate evasive maneuvers. These contributions have been validated mathematically, in simulation and in real-time operation on aerial robots, handling uncertain dynamic obstacles such as pedestrians. [less ▲]

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